OpenCloudOS-Kernel/drivers/md/dm-crypt.c

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/*
* Copyright (C) 2003 Jana Saout <jana@saout.de>
* Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
* Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved.
* Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com>
*
* This file is released under the GPL.
*/
#include <linux/completion.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/key.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/mempool.h>
#include <linux/slab.h>
#include <linux/crypto.h>
#include <linux/workqueue.h>
#include <linux/kthread.h>
#include <linux/backing-dev.h>
#include <linux/atomic.h>
#include <linux/scatterlist.h>
#include <linux/rbtree.h>
#include <linux/ctype.h>
#include <asm/page.h>
#include <asm/unaligned.h>
#include <crypto/hash.h>
#include <crypto/md5.h>
#include <crypto/algapi.h>
#include <crypto/skcipher.h>
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
#include <crypto/aead.h>
#include <crypto/authenc.h>
#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */
#include <linux/key-type.h>
#include <keys/user-type.h>
#include <keys/encrypted-type.h>
#include <linux/device-mapper.h>
#define DM_MSG_PREFIX "crypt"
/*
* context holding the current state of a multi-part conversion
*/
struct convert_context {
struct completion restart;
struct bio *bio_in;
struct bio *bio_out;
struct bvec_iter iter_in;
struct bvec_iter iter_out;
dm crypt: use u64 instead of sector_t to store iv_offset The iv_offset in the mapping table of crypt target is a 64bit number when IV algorithm is plain64, plain64be, essiv or benbi. It will be assigned to iv_offset of struct crypt_config, cc_sector of struct convert_context and iv_sector of struct dm_crypt_request. These structures members are defined as a sector_t. But sector_t is 32bit when CONFIG_LBDAF is not set in 32bit kernel. In this situation sector_t is not big enough to store the 64bit iv_offset. Here is a reproducer. Prepare test image and device (loop is automatically allocated by cryptsetup): # dd if=/dev/zero of=tst.img bs=1M count=1 # echo "tst"|cryptsetup open --type plain -c aes-xts-plain64 \ --skip 500000000000000000 tst.img test On 32bit system (use IV offset value that overflows to 64bit; CONFIG_LBDAF if off) and device checksum is wrong: # dmsetup table test --showkeys 0 2048 crypt aes-xts-plain64 dfa7cfe3c481f2239155739c42e539ae8f2d38f304dcc89d20b26f69daaf0933 3551657984 7:0 0 # sha256sum /dev/mapper/test 533e25c09176632b3794f35303488c4a8f3f965dffffa6ec2df347c168cb6c19 /dev/mapper/test On 64bit system (and on 32bit system with the patch), table and checksum is now correct: # dmsetup table test --showkeys 0 2048 crypt aes-xts-plain64 dfa7cfe3c481f2239155739c42e539ae8f2d38f304dcc89d20b26f69daaf0933 500000000000000000 7:0 0 # sha256sum /dev/mapper/test 5d16160f9d5f8c33d8051e65fdb4f003cc31cd652b5abb08f03aa6fce0df75fc /dev/mapper/test Signed-off-by: AliOS system security <alios_sys_security@linux.alibaba.com> Tested-and-Reviewed-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-11-05 15:31:42 +08:00
u64 cc_sector;
atomic_t cc_pending;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
union {
struct skcipher_request *req;
struct aead_request *req_aead;
} r;
};
/*
* per bio private data
*/
struct dm_crypt_io {
struct crypt_config *cc;
struct bio *base_bio;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
u8 *integrity_metadata;
bool integrity_metadata_from_pool;
struct work_struct work;
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
struct tasklet_struct tasklet;
struct convert_context ctx;
atomic_t io_pending;
blk_status_t error;
sector_t sector;
struct rb_node rb_node;
} CRYPTO_MINALIGN_ATTR;
struct dm_crypt_request {
struct convert_context *ctx;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
struct scatterlist sg_in[4];
struct scatterlist sg_out[4];
dm crypt: use u64 instead of sector_t to store iv_offset The iv_offset in the mapping table of crypt target is a 64bit number when IV algorithm is plain64, plain64be, essiv or benbi. It will be assigned to iv_offset of struct crypt_config, cc_sector of struct convert_context and iv_sector of struct dm_crypt_request. These structures members are defined as a sector_t. But sector_t is 32bit when CONFIG_LBDAF is not set in 32bit kernel. In this situation sector_t is not big enough to store the 64bit iv_offset. Here is a reproducer. Prepare test image and device (loop is automatically allocated by cryptsetup): # dd if=/dev/zero of=tst.img bs=1M count=1 # echo "tst"|cryptsetup open --type plain -c aes-xts-plain64 \ --skip 500000000000000000 tst.img test On 32bit system (use IV offset value that overflows to 64bit; CONFIG_LBDAF if off) and device checksum is wrong: # dmsetup table test --showkeys 0 2048 crypt aes-xts-plain64 dfa7cfe3c481f2239155739c42e539ae8f2d38f304dcc89d20b26f69daaf0933 3551657984 7:0 0 # sha256sum /dev/mapper/test 533e25c09176632b3794f35303488c4a8f3f965dffffa6ec2df347c168cb6c19 /dev/mapper/test On 64bit system (and on 32bit system with the patch), table and checksum is now correct: # dmsetup table test --showkeys 0 2048 crypt aes-xts-plain64 dfa7cfe3c481f2239155739c42e539ae8f2d38f304dcc89d20b26f69daaf0933 500000000000000000 7:0 0 # sha256sum /dev/mapper/test 5d16160f9d5f8c33d8051e65fdb4f003cc31cd652b5abb08f03aa6fce0df75fc /dev/mapper/test Signed-off-by: AliOS system security <alios_sys_security@linux.alibaba.com> Tested-and-Reviewed-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-11-05 15:31:42 +08:00
u64 iv_sector;
};
struct crypt_config;
struct crypt_iv_operations {
int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
const char *opts);
void (*dtr)(struct crypt_config *cc);
int (*init)(struct crypt_config *cc);
int (*wipe)(struct crypt_config *cc);
int (*generator)(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq);
int (*post)(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq);
};
struct iv_benbi_private {
int shift;
};
#define LMK_SEED_SIZE 64 /* hash + 0 */
struct iv_lmk_private {
struct crypto_shash *hash_tfm;
u8 *seed;
};
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
#define TCW_WHITENING_SIZE 16
struct iv_tcw_private {
struct crypto_shash *crc32_tfm;
u8 *iv_seed;
u8 *whitening;
};
#define ELEPHANT_MAX_KEY_SIZE 32
struct iv_elephant_private {
struct crypto_skcipher *tfm;
};
/*
* Crypt: maps a linear range of a block device
* and encrypts / decrypts at the same time.
*/
enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD,
DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE,
DM_CRYPT_WRITE_INLINE };
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
enum cipher_flags {
CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cihper */
CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */
CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
};
/*
dm crypt: fix cpu hotplug crash by removing per-cpu structure The DM crypt target used per-cpu structures to hold pointers to a ablkcipher_request structure. The code assumed that the work item keeps executing on a single CPU, so it didn't use synchronization when accessing this structure. If a CPU is disabled by writing 0 to /sys/devices/system/cpu/cpu*/online, the work item could be moved to another CPU. This causes dm-crypt crashes, like the following, because the code starts using an incorrect ablkcipher_request: smpboot: CPU 7 is now offline BUG: unable to handle kernel NULL pointer dereference at 0000000000000130 IP: [<ffffffffa1862b3d>] crypt_convert+0x12d/0x3c0 [dm_crypt] ... Call Trace: [<ffffffffa1864415>] ? kcryptd_crypt+0x305/0x470 [dm_crypt] [<ffffffff81062060>] ? finish_task_switch+0x40/0xc0 [<ffffffff81052a28>] ? process_one_work+0x168/0x470 [<ffffffff8105366b>] ? worker_thread+0x10b/0x390 [<ffffffff81053560>] ? manage_workers.isra.26+0x290/0x290 [<ffffffff81058d9f>] ? kthread+0xaf/0xc0 [<ffffffff81058cf0>] ? kthread_create_on_node+0x120/0x120 [<ffffffff813464ac>] ? ret_from_fork+0x7c/0xb0 [<ffffffff81058cf0>] ? kthread_create_on_node+0x120/0x120 Fix this bug by removing the per-cpu definition. The structure ablkcipher_request is accessed via a pointer from convert_context. Consequently, if the work item is rescheduled to a different CPU, the thread still uses the same ablkcipher_request. This change may undermine performance improvements intended by commit c0297721 ("dm crypt: scale to multiple cpus") on select hardware. In practice no performance difference was observed on recent hardware. But regardless, correctness is more important than performance. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-02-21 07:01:01 +08:00
* The fields in here must be read only after initialization.
*/
struct crypt_config {
struct dm_dev *dev;
sector_t start;
struct percpu_counter n_allocated_pages;
struct workqueue_struct *io_queue;
struct workqueue_struct *crypt_queue;
spinlock_t write_thread_lock;
struct task_struct *write_thread;
struct rb_root write_tree;
char *cipher_string;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
char *cipher_auth;
char *key_string;
const struct crypt_iv_operations *iv_gen_ops;
union {
struct iv_benbi_private benbi;
struct iv_lmk_private lmk;
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
struct iv_tcw_private tcw;
struct iv_elephant_private elephant;
} iv_gen_private;
dm crypt: use u64 instead of sector_t to store iv_offset The iv_offset in the mapping table of crypt target is a 64bit number when IV algorithm is plain64, plain64be, essiv or benbi. It will be assigned to iv_offset of struct crypt_config, cc_sector of struct convert_context and iv_sector of struct dm_crypt_request. These structures members are defined as a sector_t. But sector_t is 32bit when CONFIG_LBDAF is not set in 32bit kernel. In this situation sector_t is not big enough to store the 64bit iv_offset. Here is a reproducer. Prepare test image and device (loop is automatically allocated by cryptsetup): # dd if=/dev/zero of=tst.img bs=1M count=1 # echo "tst"|cryptsetup open --type plain -c aes-xts-plain64 \ --skip 500000000000000000 tst.img test On 32bit system (use IV offset value that overflows to 64bit; CONFIG_LBDAF if off) and device checksum is wrong: # dmsetup table test --showkeys 0 2048 crypt aes-xts-plain64 dfa7cfe3c481f2239155739c42e539ae8f2d38f304dcc89d20b26f69daaf0933 3551657984 7:0 0 # sha256sum /dev/mapper/test 533e25c09176632b3794f35303488c4a8f3f965dffffa6ec2df347c168cb6c19 /dev/mapper/test On 64bit system (and on 32bit system with the patch), table and checksum is now correct: # dmsetup table test --showkeys 0 2048 crypt aes-xts-plain64 dfa7cfe3c481f2239155739c42e539ae8f2d38f304dcc89d20b26f69daaf0933 500000000000000000 7:0 0 # sha256sum /dev/mapper/test 5d16160f9d5f8c33d8051e65fdb4f003cc31cd652b5abb08f03aa6fce0df75fc /dev/mapper/test Signed-off-by: AliOS system security <alios_sys_security@linux.alibaba.com> Tested-and-Reviewed-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-11-05 15:31:42 +08:00
u64 iv_offset;
unsigned int iv_size;
unsigned short int sector_size;
unsigned char sector_shift;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
union {
struct crypto_skcipher **tfms;
struct crypto_aead **tfms_aead;
} cipher_tfm;
unsigned tfms_count;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
unsigned long cipher_flags;
/*
* Layout of each crypto request:
*
* struct skcipher_request
* context
* padding
* struct dm_crypt_request
* padding
* IV
*
* The padding is added so that dm_crypt_request and the IV are
* correctly aligned.
*/
unsigned int dmreq_start;
unsigned int per_bio_data_size;
unsigned long flags;
unsigned int key_size;
unsigned int key_parts; /* independent parts in key buffer */
unsigned int key_extra_size; /* additional keys length */
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
unsigned int key_mac_size; /* MAC key size for authenc(...) */
unsigned int integrity_tag_size;
unsigned int integrity_iv_size;
unsigned int on_disk_tag_size;
/*
* pool for per bio private data, crypto requests,
* encryption requeusts/buffer pages and integrity tags
*/
unsigned tag_pool_max_sectors;
mempool_t tag_pool;
mempool_t req_pool;
mempool_t page_pool;
struct bio_set bs;
struct mutex bio_alloc_lock;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
u8 *authenc_key; /* space for keys in authenc() format (if used) */
dm: replace zero-length array with flexible-array The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-08 02:51:58 +08:00
u8 key[];
};
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
#define MIN_IOS 64
#define MAX_TAG_SIZE 480
#define POOL_ENTRY_SIZE 512
static DEFINE_SPINLOCK(dm_crypt_clients_lock);
static unsigned dm_crypt_clients_n = 0;
static volatile unsigned long dm_crypt_pages_per_client;
#define DM_CRYPT_MEMORY_PERCENT 2
#define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_PAGES * 16)
static void clone_init(struct dm_crypt_io *, struct bio *);
static void kcryptd_queue_crypt(struct dm_crypt_io *io);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
struct scatterlist *sg);
static bool crypt_integrity_aead(struct crypt_config *cc);
/*
* Use this to access cipher attributes that are independent of the key.
*/
static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
return cc->cipher_tfm.tfms[0];
}
static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
{
return cc->cipher_tfm.tfms_aead[0];
}
/*
* Different IV generation algorithms:
*
* plain: the initial vector is the 32-bit little-endian version of the sector
* number, padded with zeros if necessary.
*
* plain64: the initial vector is the 64-bit little-endian version of the sector
* number, padded with zeros if necessary.
*
* plain64be: the initial vector is the 64-bit big-endian version of the sector
* number, padded with zeros if necessary.
*
* essiv: "encrypted sector|salt initial vector", the sector number is
* encrypted with the bulk cipher using a salt as key. The salt
* should be derived from the bulk cipher's key via hashing.
*
* benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
* (needed for LRW-32-AES and possible other narrow block modes)
*
* null: the initial vector is always zero. Provides compatibility with
* obsolete loop_fish2 devices. Do not use for new devices.
*
* lmk: Compatible implementation of the block chaining mode used
* by the Loop-AES block device encryption system
* designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
* It operates on full 512 byte sectors and uses CBC
* with an IV derived from the sector number, the data and
* optionally extra IV seed.
* This means that after decryption the first block
* of sector must be tweaked according to decrypted data.
* Loop-AES can use three encryption schemes:
* version 1: is plain aes-cbc mode
* version 2: uses 64 multikey scheme with lmk IV generator
* version 3: the same as version 2 with additional IV seed
* (it uses 65 keys, last key is used as IV seed)
*
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
* tcw: Compatible implementation of the block chaining mode used
* by the TrueCrypt device encryption system (prior to version 4.1).
* For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
* It operates on full 512 byte sectors and uses CBC
* with an IV derived from initial key and the sector number.
* In addition, whitening value is applied on every sector, whitening
* is calculated from initial key, sector number and mixed using CRC32.
* Note that this encryption scheme is vulnerable to watermarking attacks
* and should be used for old compatible containers access only.
*
* eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)
* The IV is encrypted little-endian byte-offset (with the same key
* and cipher as the volume).
*
* elephant: The extended version of eboiv with additional Elephant diffuser
* used with Bitlocker CBC mode.
* This mode was used in older Windows systems
* https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf
*/
static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
*(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
return 0;
}
static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
return 0;
}
static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
/* iv_size is at least of size u64; usually it is 16 bytes */
*(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
return 0;
}
static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
/*
* ESSIV encryption of the IV is now handled by the crypto API,
* so just pass the plain sector number here.
*/
memset(iv, 0, cc->iv_size);
*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
return 0;
}
static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
unsigned bs;
int log;
if (crypt_integrity_aead(cc))
bs = crypto_aead_blocksize(any_tfm_aead(cc));
else
bs = crypto_skcipher_blocksize(any_tfm(cc));
log = ilog2(bs);
/* we need to calculate how far we must shift the sector count
* to get the cipher block count, we use this shift in _gen */
if (1 << log != bs) {
ti->error = "cypher blocksize is not a power of 2";
return -EINVAL;
}
if (log > 9) {
ti->error = "cypher blocksize is > 512";
return -EINVAL;
}
cc->iv_gen_private.benbi.shift = 9 - log;
return 0;
}
static void crypt_iv_benbi_dtr(struct crypt_config *cc)
{
}
static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
__be64 val;
memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
return 0;
}
static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
return 0;
}
static void crypt_iv_lmk_dtr(struct crypt_config *cc)
{
struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
crypto_free_shash(lmk->hash_tfm);
lmk->hash_tfm = NULL;
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(lmk->seed);
lmk->seed = NULL;
}
static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
if (cc->sector_size != (1 << SECTOR_SHIFT)) {
ti->error = "Unsupported sector size for LMK";
return -EINVAL;
}
lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
if (IS_ERR(lmk->hash_tfm)) {
ti->error = "Error initializing LMK hash";
return PTR_ERR(lmk->hash_tfm);
}
/* No seed in LMK version 2 */
if (cc->key_parts == cc->tfms_count) {
lmk->seed = NULL;
return 0;
}
lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
if (!lmk->seed) {
crypt_iv_lmk_dtr(cc);
ti->error = "Error kmallocing seed storage in LMK";
return -ENOMEM;
}
return 0;
}
static int crypt_iv_lmk_init(struct crypt_config *cc)
{
struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
int subkey_size = cc->key_size / cc->key_parts;
/* LMK seed is on the position of LMK_KEYS + 1 key */
if (lmk->seed)
memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
crypto_shash_digestsize(lmk->hash_tfm));
return 0;
}
static int crypt_iv_lmk_wipe(struct crypt_config *cc)
{
struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
if (lmk->seed)
memset(lmk->seed, 0, LMK_SEED_SIZE);
return 0;
}
static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq,
u8 *data)
{
struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
struct md5_state md5state;
__le32 buf[4];
int i, r;
desc->tfm = lmk->hash_tfm;
r = crypto_shash_init(desc);
if (r)
return r;
if (lmk->seed) {
r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
if (r)
return r;
}
/* Sector is always 512B, block size 16, add data of blocks 1-31 */
r = crypto_shash_update(desc, data + 16, 16 * 31);
if (r)
return r;
/* Sector is cropped to 56 bits here */
buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
buf[2] = cpu_to_le32(4024);
buf[3] = 0;
r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
if (r)
return r;
/* No MD5 padding here */
r = crypto_shash_export(desc, &md5state);
if (r)
return r;
for (i = 0; i < MD5_HASH_WORDS; i++)
__cpu_to_le32s(&md5state.hash[i]);
memcpy(iv, &md5state.hash, cc->iv_size);
return 0;
}
static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
struct scatterlist *sg;
u8 *src;
int r = 0;
if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg = crypt_get_sg_data(cc, dmreq->sg_in);
src = kmap_atomic(sg_page(sg));
r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
kunmap_atomic(src);
} else
memset(iv, 0, cc->iv_size);
return r;
}
static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
struct scatterlist *sg;
u8 *dst;
int r;
if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
return 0;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg = crypt_get_sg_data(cc, dmreq->sg_out);
dst = kmap_atomic(sg_page(sg));
r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
/* Tweak the first block of plaintext sector */
if (!r)
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
crypto_xor(dst + sg->offset, iv, cc->iv_size);
kunmap_atomic(dst);
return r;
}
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
static void crypt_iv_tcw_dtr(struct crypt_config *cc)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(tcw->iv_seed);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
tcw->iv_seed = NULL;
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(tcw->whitening);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
tcw->whitening = NULL;
if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
crypto_free_shash(tcw->crc32_tfm);
tcw->crc32_tfm = NULL;
}
static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
if (cc->sector_size != (1 << SECTOR_SHIFT)) {
ti->error = "Unsupported sector size for TCW";
return -EINVAL;
}
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
ti->error = "Wrong key size for TCW";
return -EINVAL;
}
tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0);
if (IS_ERR(tcw->crc32_tfm)) {
ti->error = "Error initializing CRC32 in TCW";
return PTR_ERR(tcw->crc32_tfm);
}
tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
if (!tcw->iv_seed || !tcw->whitening) {
crypt_iv_tcw_dtr(cc);
ti->error = "Error allocating seed storage in TCW";
return -ENOMEM;
}
return 0;
}
static int crypt_iv_tcw_init(struct crypt_config *cc)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
TCW_WHITENING_SIZE);
return 0;
}
static int crypt_iv_tcw_wipe(struct crypt_config *cc)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
memset(tcw->iv_seed, 0, cc->iv_size);
memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
return 0;
}
static int crypt_iv_tcw_whitening(struct crypt_config *cc,
struct dm_crypt_request *dmreq,
u8 *data)
{
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
__le64 sector = cpu_to_le64(dmreq->iv_sector);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
u8 buf[TCW_WHITENING_SIZE];
SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
int i, r;
/* xor whitening with sector number */
crypto_xor_cpy(buf, tcw->whitening, (u8 *)&sector, 8);
crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)&sector, 8);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
/* calculate crc32 for every 32bit part and xor it */
desc->tfm = tcw->crc32_tfm;
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
for (i = 0; i < 4; i++) {
r = crypto_shash_init(desc);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
if (r)
goto out;
r = crypto_shash_update(desc, &buf[i * 4], 4);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
if (r)
goto out;
r = crypto_shash_final(desc, &buf[i * 4]);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
if (r)
goto out;
}
crypto_xor(&buf[0], &buf[12], 4);
crypto_xor(&buf[4], &buf[8], 4);
/* apply whitening (8 bytes) to whole sector */
for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
crypto_xor(data + i * 8, buf, 8);
out:
memzero_explicit(buf, sizeof(buf));
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
return r;
}
static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
struct scatterlist *sg;
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
__le64 sector = cpu_to_le64(dmreq->iv_sector);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
u8 *src;
int r = 0;
/* Remove whitening from ciphertext */
if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg = crypt_get_sg_data(cc, dmreq->sg_in);
src = kmap_atomic(sg_page(sg));
r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
kunmap_atomic(src);
}
/* Calculate IV */
crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)&sector, 8);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
if (cc->iv_size > 8)
crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)&sector,
cc->iv_size - 8);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
return r;
}
static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
struct scatterlist *sg;
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
u8 *dst;
int r;
if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
return 0;
/* Apply whitening on ciphertext */
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg = crypt_get_sg_data(cc, dmreq->sg_out);
dst = kmap_atomic(sg_page(sg));
r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
kunmap_atomic(dst);
return r;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
/* Used only for writes, there must be an additional space to store IV */
get_random_bytes(iv, cc->iv_size);
return 0;
}
static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
if (crypt_integrity_aead(cc)) {
ti->error = "AEAD transforms not supported for EBOIV";
return -EINVAL;
}
if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) {
ti->error = "Block size of EBOIV cipher does "
"not match IV size of block cipher";
return -EINVAL;
}
return 0;
}
static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64));
struct skcipher_request *req;
struct scatterlist src, dst;
DECLARE_CRYPTO_WAIT(wait);
int err;
req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO);
if (!req)
return -ENOMEM;
memset(buf, 0, cc->iv_size);
*(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size);
sg_init_one(&dst, iv, cc->iv_size);
skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf);
skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
skcipher_request_free(req);
return err;
}
static void crypt_iv_elephant_dtr(struct crypt_config *cc)
{
struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
crypto_free_skcipher(elephant->tfm);
elephant->tfm = NULL;
}
static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
int r;
elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
if (IS_ERR(elephant->tfm)) {
r = PTR_ERR(elephant->tfm);
elephant->tfm = NULL;
return r;
}
r = crypt_iv_eboiv_ctr(cc, ti, NULL);
if (r)
crypt_iv_elephant_dtr(cc);
return r;
}
static void diffuser_disk_to_cpu(u32 *d, size_t n)
{
#ifndef __LITTLE_ENDIAN
int i;
for (i = 0; i < n; i++)
d[i] = le32_to_cpu((__le32)d[i]);
#endif
}
static void diffuser_cpu_to_disk(__le32 *d, size_t n)
{
#ifndef __LITTLE_ENDIAN
int i;
for (i = 0; i < n; i++)
d[i] = cpu_to_le32((u32)d[i]);
#endif
}
static void diffuser_a_decrypt(u32 *d, size_t n)
{
int i, i1, i2, i3;
for (i = 0; i < 5; i++) {
i1 = 0;
i2 = n - 2;
i3 = n - 5;
while (i1 < (n - 1)) {
d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
i1++; i2++; i3++;
if (i3 >= n)
i3 -= n;
d[i1] += d[i2] ^ d[i3];
i1++; i2++; i3++;
if (i2 >= n)
i2 -= n;
d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
i1++; i2++; i3++;
d[i1] += d[i2] ^ d[i3];
i1++; i2++; i3++;
}
}
}
static void diffuser_a_encrypt(u32 *d, size_t n)
{
int i, i1, i2, i3;
for (i = 0; i < 5; i++) {
i1 = n - 1;
i2 = n - 2 - 1;
i3 = n - 5 - 1;
while (i1 > 0) {
d[i1] -= d[i2] ^ d[i3];
i1--; i2--; i3--;
d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
i1--; i2--; i3--;
if (i2 < 0)
i2 += n;
d[i1] -= d[i2] ^ d[i3];
i1--; i2--; i3--;
if (i3 < 0)
i3 += n;
d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
i1--; i2--; i3--;
}
}
}
static void diffuser_b_decrypt(u32 *d, size_t n)
{
int i, i1, i2, i3;
for (i = 0; i < 3; i++) {
i1 = 0;
i2 = 2;
i3 = 5;
while (i1 < (n - 1)) {
d[i1] += d[i2] ^ d[i3];
i1++; i2++; i3++;
d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
i1++; i2++; i3++;
if (i2 >= n)
i2 -= n;
d[i1] += d[i2] ^ d[i3];
i1++; i2++; i3++;
if (i3 >= n)
i3 -= n;
d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
i1++; i2++; i3++;
}
}
}
static void diffuser_b_encrypt(u32 *d, size_t n)
{
int i, i1, i2, i3;
for (i = 0; i < 3; i++) {
i1 = n - 1;
i2 = 2 - 1;
i3 = 5 - 1;
while (i1 > 0) {
d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
i1--; i2--; i3--;
if (i3 < 0)
i3 += n;
d[i1] -= d[i2] ^ d[i3];
i1--; i2--; i3--;
if (i2 < 0)
i2 += n;
d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
i1--; i2--; i3--;
d[i1] -= d[i2] ^ d[i3];
i1--; i2--; i3--;
}
}
}
static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq)
{
struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
u8 *es, *ks, *data, *data2, *data_offset;
struct skcipher_request *req;
struct scatterlist *sg, *sg2, src, dst;
DECLARE_CRYPTO_WAIT(wait);
int i, r;
req = skcipher_request_alloc(elephant->tfm, GFP_NOIO);
es = kzalloc(16, GFP_NOIO); /* Key for AES */
ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */
if (!req || !es || !ks) {
r = -ENOMEM;
goto out;
}
*(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
/* E(Ks, e(s)) */
sg_init_one(&src, es, 16);
sg_init_one(&dst, ks, 16);
skcipher_request_set_crypt(req, &src, &dst, 16, NULL);
skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
if (r)
goto out;
/* E(Ks, e'(s)) */
es[15] = 0x80;
sg_init_one(&dst, &ks[16], 16);
r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
if (r)
goto out;
sg = crypt_get_sg_data(cc, dmreq->sg_out);
data = kmap_atomic(sg_page(sg));
data_offset = data + sg->offset;
/* Cannot modify original bio, copy to sg_out and apply Elephant to it */
if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
sg2 = crypt_get_sg_data(cc, dmreq->sg_in);
data2 = kmap_atomic(sg_page(sg2));
memcpy(data_offset, data2 + sg2->offset, cc->sector_size);
kunmap_atomic(data2);
}
if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
}
for (i = 0; i < (cc->sector_size / 32); i++)
crypto_xor(data_offset + i * 32, ks, 32);
if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
}
kunmap_atomic(data);
out:
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(ks);
kfree_sensitive(es);
skcipher_request_free(req);
return r;
}
static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
int r;
if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
r = crypt_iv_elephant(cc, dmreq);
if (r)
return r;
}
return crypt_iv_eboiv_gen(cc, iv, dmreq);
}
static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
return crypt_iv_elephant(cc, dmreq);
return 0;
}
static int crypt_iv_elephant_init(struct crypt_config *cc)
{
struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
int key_offset = cc->key_size - cc->key_extra_size;
return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size);
}
static int crypt_iv_elephant_wipe(struct crypt_config *cc)
{
struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
u8 key[ELEPHANT_MAX_KEY_SIZE];
memset(key, 0, cc->key_extra_size);
return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size);
}
static const struct crypt_iv_operations crypt_iv_plain_ops = {
.generator = crypt_iv_plain_gen
};
static const struct crypt_iv_operations crypt_iv_plain64_ops = {
.generator = crypt_iv_plain64_gen
};
static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
.generator = crypt_iv_plain64be_gen
};
static const struct crypt_iv_operations crypt_iv_essiv_ops = {
.generator = crypt_iv_essiv_gen
};
static const struct crypt_iv_operations crypt_iv_benbi_ops = {
.ctr = crypt_iv_benbi_ctr,
.dtr = crypt_iv_benbi_dtr,
.generator = crypt_iv_benbi_gen
};
static const struct crypt_iv_operations crypt_iv_null_ops = {
.generator = crypt_iv_null_gen
};
static const struct crypt_iv_operations crypt_iv_lmk_ops = {
.ctr = crypt_iv_lmk_ctr,
.dtr = crypt_iv_lmk_dtr,
.init = crypt_iv_lmk_init,
.wipe = crypt_iv_lmk_wipe,
.generator = crypt_iv_lmk_gen,
.post = crypt_iv_lmk_post
};
static const struct crypt_iv_operations crypt_iv_tcw_ops = {
dm crypt: add TCW IV mode for old CBC TCRYPT containers dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-10-29 06:21:04 +08:00
.ctr = crypt_iv_tcw_ctr,
.dtr = crypt_iv_tcw_dtr,
.init = crypt_iv_tcw_init,
.wipe = crypt_iv_tcw_wipe,
.generator = crypt_iv_tcw_gen,
.post = crypt_iv_tcw_post
};
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static struct crypt_iv_operations crypt_iv_random_ops = {
.generator = crypt_iv_random_gen
};
static struct crypt_iv_operations crypt_iv_eboiv_ops = {
.ctr = crypt_iv_eboiv_ctr,
.generator = crypt_iv_eboiv_gen
};
static struct crypt_iv_operations crypt_iv_elephant_ops = {
.ctr = crypt_iv_elephant_ctr,
.dtr = crypt_iv_elephant_dtr,
.init = crypt_iv_elephant_init,
.wipe = crypt_iv_elephant_wipe,
.generator = crypt_iv_elephant_gen,
.post = crypt_iv_elephant_post
};
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/*
* Integrity extensions
*/
static bool crypt_integrity_aead(struct crypt_config *cc)
{
return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
}
static bool crypt_integrity_hmac(struct crypt_config *cc)
{
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
return crypt_integrity_aead(cc) && cc->key_mac_size;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
}
/* Get sg containing data */
static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
struct scatterlist *sg)
{
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (unlikely(crypt_integrity_aead(cc)))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
return &sg[2];
return sg;
}
static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
{
struct bio_integrity_payload *bip;
unsigned int tag_len;
int ret;
if (!bio_sectors(bio) || !io->cc->on_disk_tag_size)
return 0;
bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
if (IS_ERR(bip))
return PTR_ERR(bip);
tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
bip->bip_iter.bi_size = tag_len;
bip->bip_iter.bi_sector = io->cc->start + io->sector;
ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
tag_len, offset_in_page(io->integrity_metadata));
if (unlikely(ret != tag_len))
return -ENOMEM;
return 0;
}
static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
{
#ifdef CONFIG_BLK_DEV_INTEGRITY
struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
struct mapped_device *md = dm_table_get_md(ti->table);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/* From now we require underlying device with our integrity profile */
if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) {
ti->error = "Integrity profile not supported.";
return -EINVAL;
}
if (bi->tag_size != cc->on_disk_tag_size ||
bi->tuple_size != cc->on_disk_tag_size) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
ti->error = "Integrity profile tag size mismatch.";
return -EINVAL;
}
if (1 << bi->interval_exp != cc->sector_size) {
ti->error = "Integrity profile sector size mismatch.";
return -EINVAL;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc)) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size;
DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md),
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
cc->integrity_tag_size, cc->integrity_iv_size);
if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
ti->error = "Integrity AEAD auth tag size is not supported.";
return -EINVAL;
}
} else if (cc->integrity_iv_size)
DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md),
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
cc->integrity_iv_size);
if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) {
ti->error = "Not enough space for integrity tag in the profile.";
return -EINVAL;
}
return 0;
#else
ti->error = "Integrity profile not supported.";
return -EINVAL;
#endif
}
static void crypt_convert_init(struct crypt_config *cc,
struct convert_context *ctx,
struct bio *bio_out, struct bio *bio_in,
sector_t sector)
{
ctx->bio_in = bio_in;
ctx->bio_out = bio_out;
if (bio_in)
ctx->iter_in = bio_in->bi_iter;
if (bio_out)
ctx->iter_out = bio_out->bi_iter;
ctx->cc_sector = sector + cc->iv_offset;
init_completion(&ctx->restart);
}
static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
void *req)
{
return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
return (void *)((char *)dmreq - cc->dmreq_start);
}
static u8 *iv_of_dmreq(struct crypt_config *cc,
struct dm_crypt_request *dmreq)
{
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
return (u8 *)ALIGN((unsigned long)(dmreq + 1),
crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
else
return (u8 *)ALIGN((unsigned long)(dmreq + 1),
crypto_skcipher_alignmask(any_tfm(cc)) + 1);
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static u8 *org_iv_of_dmreq(struct crypt_config *cc,
struct dm_crypt_request *dmreq)
{
return iv_of_dmreq(cc, dmreq) + cc->iv_size;
}
static __le64 *org_sector_of_dmreq(struct crypt_config *cc,
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
struct dm_crypt_request *dmreq)
{
u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
return (__le64 *) ptr;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
}
static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
struct dm_crypt_request *dmreq)
{
u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
cc->iv_size + sizeof(uint64_t);
return (unsigned int*)ptr;
}
static void *tag_from_dmreq(struct crypt_config *cc,
struct dm_crypt_request *dmreq)
{
struct convert_context *ctx = dmreq->ctx;
struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
cc->on_disk_tag_size];
}
static void *iv_tag_from_dmreq(struct crypt_config *cc,
struct dm_crypt_request *dmreq)
{
return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
}
static int crypt_convert_block_aead(struct crypt_config *cc,
struct convert_context *ctx,
struct aead_request *req,
unsigned int tag_offset)
{
struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
struct dm_crypt_request *dmreq;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
u8 *iv, *org_iv, *tag_iv, *tag;
__le64 *sector;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
int r = 0;
BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
/* Reject unexpected unaligned bio. */
if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
return -EIO;
dmreq = dmreq_of_req(cc, req);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
dmreq->iv_sector = ctx->cc_sector;
if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
dmreq->iv_sector >>= cc->sector_shift;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
dmreq->ctx = ctx;
*org_tag_of_dmreq(cc, dmreq) = tag_offset;
sector = org_sector_of_dmreq(cc, dmreq);
*sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
iv = iv_of_dmreq(cc, dmreq);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
org_iv = org_iv_of_dmreq(cc, dmreq);
tag = tag_from_dmreq(cc, dmreq);
tag_iv = iv_tag_from_dmreq(cc, dmreq);
/* AEAD request:
* |----- AAD -------|------ DATA -------|-- AUTH TAG --|
* | (authenticated) | (auth+encryption) | |
* | sector_LE | IV | sector in/out | tag in/out |
*/
sg_init_table(dmreq->sg_in, 4);
sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
sg_init_table(dmreq->sg_out, 4);
sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
if (cc->iv_gen_ops) {
/* For READs use IV stored in integrity metadata */
if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
memcpy(org_iv, tag_iv, cc->iv_size);
} else {
r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
if (r < 0)
return r;
/* Store generated IV in integrity metadata */
if (cc->integrity_iv_size)
memcpy(tag_iv, org_iv, cc->iv_size);
}
/* Working copy of IV, to be modified in crypto API */
memcpy(iv, org_iv, cc->iv_size);
}
aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
if (bio_data_dir(ctx->bio_in) == WRITE) {
aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
cc->sector_size, iv);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
r = crypto_aead_encrypt(req);
if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size)
memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size));
} else {
aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
cc->sector_size + cc->integrity_tag_size, iv);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
r = crypto_aead_decrypt(req);
}
if (r == -EBADMSG) {
char b[BDEVNAME_SIZE];
DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b),
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
(unsigned long long)le64_to_cpu(*sector));
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
return r;
}
static int crypt_convert_block_skcipher(struct crypt_config *cc,
struct convert_context *ctx,
struct skcipher_request *req,
unsigned int tag_offset)
{
struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
struct scatterlist *sg_in, *sg_out;
struct dm_crypt_request *dmreq;
u8 *iv, *org_iv, *tag_iv;
__le64 *sector;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
int r = 0;
/* Reject unexpected unaligned bio. */
if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
return -EIO;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
dmreq = dmreq_of_req(cc, req);
dmreq->iv_sector = ctx->cc_sector;
if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
dmreq->iv_sector >>= cc->sector_shift;
dmreq->ctx = ctx;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
*org_tag_of_dmreq(cc, dmreq) = tag_offset;
iv = iv_of_dmreq(cc, dmreq);
org_iv = org_iv_of_dmreq(cc, dmreq);
tag_iv = iv_tag_from_dmreq(cc, dmreq);
sector = org_sector_of_dmreq(cc, dmreq);
*sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
/* For skcipher we use only the first sg item */
sg_in = &dmreq->sg_in[0];
sg_out = &dmreq->sg_out[0];
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg_init_table(sg_in, 1);
sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
sg_init_table(sg_out, 1);
sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
if (cc->iv_gen_ops) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/* For READs use IV stored in integrity metadata */
if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
memcpy(org_iv, tag_iv, cc->integrity_iv_size);
} else {
r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
if (r < 0)
return r;
/* Data can be already preprocessed in generator */
if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags))
sg_in = sg_out;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/* Store generated IV in integrity metadata */
if (cc->integrity_iv_size)
memcpy(tag_iv, org_iv, cc->integrity_iv_size);
}
/* Working copy of IV, to be modified in crypto API */
memcpy(iv, org_iv, cc->iv_size);
}
skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
if (bio_data_dir(ctx->bio_in) == WRITE)
r = crypto_skcipher_encrypt(req);
else
r = crypto_skcipher_decrypt(req);
if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
return r;
}
static void kcryptd_async_done(struct crypto_async_request *async_req,
int error);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void crypt_alloc_req_skcipher(struct crypt_config *cc,
struct convert_context *ctx)
{
unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (!ctx->r.req)
ctx->r.req = mempool_alloc(&cc->req_pool, GFP_NOIO);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
/*
* Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
* requests if driver request queue is full.
*/
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
skcipher_request_set_callback(ctx->r.req,
CRYPTO_TFM_REQ_MAY_BACKLOG,
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void crypt_alloc_req_aead(struct crypt_config *cc,
struct convert_context *ctx)
{
if (!ctx->r.req_aead)
ctx->r.req_aead = mempool_alloc(&cc->req_pool, GFP_NOIO);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
/*
* Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
* requests if driver request queue is full.
*/
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
aead_request_set_callback(ctx->r.req_aead,
CRYPTO_TFM_REQ_MAY_BACKLOG,
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
}
static void crypt_alloc_req(struct crypt_config *cc,
struct convert_context *ctx)
{
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
crypt_alloc_req_aead(cc, ctx);
else
crypt_alloc_req_skcipher(cc, ctx);
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void crypt_free_req_skcipher(struct crypt_config *cc,
struct skcipher_request *req, struct bio *base_bio)
{
struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
if ((struct skcipher_request *)(io + 1) != req)
mempool_free(req, &cc->req_pool);
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void crypt_free_req_aead(struct crypt_config *cc,
struct aead_request *req, struct bio *base_bio)
{
struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
if ((struct aead_request *)(io + 1) != req)
mempool_free(req, &cc->req_pool);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
}
static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
{
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
crypt_free_req_aead(cc, req, base_bio);
else
crypt_free_req_skcipher(cc, req, base_bio);
}
/*
* Encrypt / decrypt data from one bio to another one (can be the same one)
*/
static blk_status_t crypt_convert(struct crypt_config *cc,
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
struct convert_context *ctx, bool atomic)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
unsigned int tag_offset = 0;
unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
int r;
atomic_set(&ctx->cc_pending, 1);
while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
crypt_alloc_req(cc, ctx);
atomic_inc(&ctx->cc_pending);
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset);
else
r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset);
switch (r) {
/*
* The request was queued by a crypto driver
* but the driver request queue is full, let's wait.
*/
case -EBUSY:
wait_for_completion(&ctx->restart);
reinit_completion(&ctx->restart);
fallthrough;
/*
* The request is queued and processed asynchronously,
* completion function kcryptd_async_done() will be called.
*/
Revert "dm crypt: fix deadlock when async crypto algorithm returns -EBUSY" This reverts Linux 4.1-rc1 commit 0618764cb25f6fa9fb31152995de42a8a0496475. The problem which that commit attempts to fix actually lies in the Freescale CAAM crypto driver not dm-crypt. dm-crypt uses CRYPTO_TFM_REQ_MAY_BACKLOG. This means the the crypto driver should internally backlog requests which arrive when the queue is full and process them later. Until the crypto hw's queue becomes full, the driver returns -EINPROGRESS. When the crypto hw's queue if full, the driver returns -EBUSY, and if CRYPTO_TFM_REQ_MAY_BACKLOG is set, is expected to backlog the request and process it when the hardware has queue space. At the point when the driver takes the request from the backlog and starts processing it, it calls the completion function with a status of -EINPROGRESS. The completion function is called (for a second time, in the case of backlogged requests) with a status/err of 0 when a request is done. Crypto drivers for hardware without hardware queueing use the helpers, crypto_init_queue(), crypto_enqueue_request(), crypto_dequeue_request() and crypto_get_backlog() helpers to implement this behaviour correctly, while others implement this behaviour without these helpers (ccp, for example). dm-crypt (before the patch that needs reverting) uses this API correctly. It queues up as many requests as the hw queues will allow (i.e. as long as it gets back -EINPROGRESS from the request function). Then, when it sees at least one backlogged request (gets -EBUSY), it waits till that backlogged request is handled (completion gets called with -EINPROGRESS), and then continues. The references to af_alg_wait_for_completion() and af_alg_complete() in that commit's commit message are irrelevant because those functions only handle one request at a time, unlink dm-crypt. The problem is that the Freescale CAAM driver, which that commit describes as having being tested with, fails to implement the backlogging behaviour correctly. In cam_jr_enqueue(), if the hardware queue is full, it simply returns -EBUSY without backlogging the request. What the observed deadlock was is not described in the commit message but it is obviously the wait_for_completion() in crypto_convert() where dm-crypto would wait for the completion being called with -EINPROGRESS in the case of backlogged requests. This completion will never be completed due to the bug in the CAAM driver. Commit 0618764cb25 incorrectly made dm-crypt wait for every request, even when the driver/hardware queues are not full, which means that dm-crypt will never see -EBUSY. This means that that commit will cause a performance regression on all crypto drivers which implement the API correctly. Revert it. Correct backlog handling should be implemented in the CAAM driver instead. Cc'ing stable purely because commit 0618764cb25 did. If for some reason a stable@ kernel did pick up commit 0618764cb25 it should get reverted. Signed-off-by: Rabin Vincent <rabin.vincent@axis.com> Reviewed-by: Horia Geanta <horia.geanta@freescale.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-05-05 21:15:56 +08:00
case -EINPROGRESS:
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
ctx->r.req = NULL;
ctx->cc_sector += sector_step;
tag_offset++;
continue;
/*
* The request was already processed (synchronously).
*/
case 0:
atomic_dec(&ctx->cc_pending);
ctx->cc_sector += sector_step;
tag_offset++;
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
if (!atomic)
cond_resched();
continue;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/*
* There was a data integrity error.
*/
case -EBADMSG:
atomic_dec(&ctx->cc_pending);
return BLK_STS_PROTECTION;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/*
* There was an error while processing the request.
*/
default:
atomic_dec(&ctx->cc_pending);
return BLK_STS_IOERR;
}
}
return 0;
}
static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
/*
* Generate a new unfragmented bio with the given size
dm crypt: constrain crypt device's max_segment_size to PAGE_SIZE Setting the dm-crypt device's max_segment_size to PAGE_SIZE is an unfortunate constraint that is required to avoid the potential for exceeding dm-crypt's underlying device's max_segments limits -- due to crypt_alloc_buffer() possibly allocating pages for the encryption bio that are not as physically contiguous as the original bio. It is interesting to note that this problem was already fixed back in 2007 via commit 91e106259 ("dm crypt: use bio_add_page"). But Linux 4.0 commit cf2f1abfb ("dm crypt: don't allocate pages for a partial request") regressed dm-crypt back to _not_ using bio_add_page(). But given dm-crypt's cpu parallelization changes all depend on commit cf2f1abfb's abandoning of the more complex io fragments processing that dm-crypt previously had we cannot easily go back to using bio_add_page(). So all said the cleanest way to resolve this issue is to fix dm-crypt to properly constrain the original bios entering dm-crypt so the encryption bios that dm-crypt generates from the original bios are always compatible with the underlying device's max_segments queue limits. It should be noted that technically Linux 4.3 does _not_ need this fix because of the block core's new late bio-splitting capability. But, it is reasoned, there is little to be gained by having the block core split the encrypted bio that is composed of PAGE_SIZE segments. That said, in the future we may revert this change. Fixes: cf2f1abfb ("dm crypt: don't allocate pages for a partial request") Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=104421 Suggested-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.0+
2015-09-10 09:34:51 +08:00
* This should never violate the device limitations (but only because
* max_segment_size is being constrained to PAGE_SIZE).
*
* This function may be called concurrently. If we allocate from the mempool
* concurrently, there is a possibility of deadlock. For example, if we have
* mempool of 256 pages, two processes, each wanting 256, pages allocate from
* the mempool concurrently, it may deadlock in a situation where both processes
* have allocated 128 pages and the mempool is exhausted.
*
* In order to avoid this scenario we allocate the pages under a mutex.
*
* In order to not degrade performance with excessive locking, we try
* non-blocking allocations without a mutex first but on failure we fallback
* to blocking allocations with a mutex.
*/
static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
{
struct crypt_config *cc = io->cc;
struct bio *clone;
unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
unsigned i, len, remaining_size;
struct page *page;
retry:
mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd __GFP_WAIT has been used to identify atomic context in callers that hold spinlocks or are in interrupts. They are expected to be high priority and have access one of two watermarks lower than "min" which can be referred to as the "atomic reserve". __GFP_HIGH users get access to the first lower watermark and can be called the "high priority reserve". Over time, callers had a requirement to not block when fallback options were available. Some have abused __GFP_WAIT leading to a situation where an optimisitic allocation with a fallback option can access atomic reserves. This patch uses __GFP_ATOMIC to identify callers that are truely atomic, cannot sleep and have no alternative. High priority users continue to use __GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify callers that want to wake kswapd for background reclaim. __GFP_WAIT is redefined as a caller that is willing to enter direct reclaim and wake kswapd for background reclaim. This patch then converts a number of sites o __GFP_ATOMIC is used by callers that are high priority and have memory pools for those requests. GFP_ATOMIC uses this flag. o Callers that have a limited mempool to guarantee forward progress clear __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall into this category where kswapd will still be woken but atomic reserves are not used as there is a one-entry mempool to guarantee progress. o Callers that are checking if they are non-blocking should use the helper gfpflags_allow_blocking() where possible. This is because checking for __GFP_WAIT as was done historically now can trigger false positives. Some exceptions like dm-crypt.c exist where the code intent is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to flag manipulations. o Callers that built their own GFP flags instead of starting with GFP_KERNEL and friends now also need to specify __GFP_KSWAPD_RECLAIM. The first key hazard to watch out for is callers that removed __GFP_WAIT and was depending on access to atomic reserves for inconspicuous reasons. In some cases it may be appropriate for them to use __GFP_HIGH. The second key hazard is callers that assembled their own combination of GFP flags instead of starting with something like GFP_KERNEL. They may now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless if it's missed in most cases as other activity will wake kswapd. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:28:21 +08:00
if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
mutex_lock(&cc->bio_alloc_lock);
clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs);
if (!clone)
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
goto out;
clone_init(io, clone);
remaining_size = size;
for (i = 0; i < nr_iovecs; i++) {
page = mempool_alloc(&cc->page_pool, gfp_mask);
if (!page) {
crypt_free_buffer_pages(cc, clone);
bio_put(clone);
mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd __GFP_WAIT has been used to identify atomic context in callers that hold spinlocks or are in interrupts. They are expected to be high priority and have access one of two watermarks lower than "min" which can be referred to as the "atomic reserve". __GFP_HIGH users get access to the first lower watermark and can be called the "high priority reserve". Over time, callers had a requirement to not block when fallback options were available. Some have abused __GFP_WAIT leading to a situation where an optimisitic allocation with a fallback option can access atomic reserves. This patch uses __GFP_ATOMIC to identify callers that are truely atomic, cannot sleep and have no alternative. High priority users continue to use __GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify callers that want to wake kswapd for background reclaim. __GFP_WAIT is redefined as a caller that is willing to enter direct reclaim and wake kswapd for background reclaim. This patch then converts a number of sites o __GFP_ATOMIC is used by callers that are high priority and have memory pools for those requests. GFP_ATOMIC uses this flag. o Callers that have a limited mempool to guarantee forward progress clear __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall into this category where kswapd will still be woken but atomic reserves are not used as there is a one-entry mempool to guarantee progress. o Callers that are checking if they are non-blocking should use the helper gfpflags_allow_blocking() where possible. This is because checking for __GFP_WAIT as was done historically now can trigger false positives. Some exceptions like dm-crypt.c exist where the code intent is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to flag manipulations. o Callers that built their own GFP flags instead of starting with GFP_KERNEL and friends now also need to specify __GFP_KSWAPD_RECLAIM. The first key hazard to watch out for is callers that removed __GFP_WAIT and was depending on access to atomic reserves for inconspicuous reasons. In some cases it may be appropriate for them to use __GFP_HIGH. The second key hazard is callers that assembled their own combination of GFP flags instead of starting with something like GFP_KERNEL. They may now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless if it's missed in most cases as other activity will wake kswapd. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:28:21 +08:00
gfp_mask |= __GFP_DIRECT_RECLAIM;
goto retry;
}
len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size;
bio_add_page(clone, page, len, 0);
remaining_size -= len;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/* Allocate space for integrity tags */
if (dm_crypt_integrity_io_alloc(io, clone)) {
crypt_free_buffer_pages(cc, clone);
bio_put(clone);
clone = NULL;
}
out:
mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd __GFP_WAIT has been used to identify atomic context in callers that hold spinlocks or are in interrupts. They are expected to be high priority and have access one of two watermarks lower than "min" which can be referred to as the "atomic reserve". __GFP_HIGH users get access to the first lower watermark and can be called the "high priority reserve". Over time, callers had a requirement to not block when fallback options were available. Some have abused __GFP_WAIT leading to a situation where an optimisitic allocation with a fallback option can access atomic reserves. This patch uses __GFP_ATOMIC to identify callers that are truely atomic, cannot sleep and have no alternative. High priority users continue to use __GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify callers that want to wake kswapd for background reclaim. __GFP_WAIT is redefined as a caller that is willing to enter direct reclaim and wake kswapd for background reclaim. This patch then converts a number of sites o __GFP_ATOMIC is used by callers that are high priority and have memory pools for those requests. GFP_ATOMIC uses this flag. o Callers that have a limited mempool to guarantee forward progress clear __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall into this category where kswapd will still be woken but atomic reserves are not used as there is a one-entry mempool to guarantee progress. o Callers that are checking if they are non-blocking should use the helper gfpflags_allow_blocking() where possible. This is because checking for __GFP_WAIT as was done historically now can trigger false positives. Some exceptions like dm-crypt.c exist where the code intent is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to flag manipulations. o Callers that built their own GFP flags instead of starting with GFP_KERNEL and friends now also need to specify __GFP_KSWAPD_RECLAIM. The first key hazard to watch out for is callers that removed __GFP_WAIT and was depending on access to atomic reserves for inconspicuous reasons. In some cases it may be appropriate for them to use __GFP_HIGH. The second key hazard is callers that assembled their own combination of GFP flags instead of starting with something like GFP_KERNEL. They may now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless if it's missed in most cases as other activity will wake kswapd. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07 08:28:21 +08:00
if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
mutex_unlock(&cc->bio_alloc_lock);
return clone;
}
static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
{
struct bio_vec *bv;
struct bvec_iter_all iter_all;
bio_for_each_segment_all(bv, clone, iter_all) {
BUG_ON(!bv->bv_page);
mempool_free(bv->bv_page, &cc->page_pool);
}
}
static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
struct bio *bio, sector_t sector)
{
io->cc = cc;
io->base_bio = bio;
io->sector = sector;
io->error = 0;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
io->ctx.r.req = NULL;
io->integrity_metadata = NULL;
io->integrity_metadata_from_pool = false;
atomic_set(&io->io_pending, 0);
}
static void crypt_inc_pending(struct dm_crypt_io *io)
{
atomic_inc(&io->io_pending);
}
/*
* One of the bios was finished. Check for completion of
* the whole request and correctly clean up the buffer.
*/
static void crypt_dec_pending(struct dm_crypt_io *io)
{
struct crypt_config *cc = io->cc;
struct bio *base_bio = io->base_bio;
blk_status_t error = io->error;
if (!atomic_dec_and_test(&io->io_pending))
return;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (io->ctx.r.req)
crypt_free_req(cc, io->ctx.r.req, base_bio);
if (unlikely(io->integrity_metadata_from_pool))
mempool_free(io->integrity_metadata, &io->cc->tag_pool);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
else
kfree(io->integrity_metadata);
base_bio->bi_status = error;
bio_endio(base_bio);
}
/*
* kcryptd/kcryptd_io:
*
* Needed because it would be very unwise to do decryption in an
* interrupt context.
*
* kcryptd performs the actual encryption or decryption.
*
* kcryptd_io performs the IO submission.
*
* They must be separated as otherwise the final stages could be
* starved by new requests which can block in the first stages due
* to memory allocation.
*
* The work is done per CPU global for all dm-crypt instances.
* They should not depend on each other and do not block.
*/
static void crypt_endio(struct bio *clone)
{
struct dm_crypt_io *io = clone->bi_private;
struct crypt_config *cc = io->cc;
unsigned rw = bio_data_dir(clone);
blk_status_t error;
/*
* free the processed pages
*/
if (rw == WRITE)
crypt_free_buffer_pages(cc, clone);
error = clone->bi_status;
bio_put(clone);
block: don't access bio->bi_error after bio_put() Commit 4246a0b6 ("block: add a bi_error field to struct bio") has added a few dereferences of 'bio' after a call to bio_put(). This causes use-after-frees such as: [521120.719695] BUG: KASan: use after free in dio_bio_complete+0x2b3/0x320 at addr ffff880f36b38714 [521120.720638] Read of size 4 by task mount.ocfs2/9644 [521120.721212] ============================================================================= [521120.722056] BUG kmalloc-256 (Not tainted): kasan: bad access detected [521120.722968] ----------------------------------------------------------------------------- [521120.722968] [521120.723915] Disabling lock debugging due to kernel taint [521120.724539] INFO: Slab 0xffffea003cdace00 objects=32 used=25 fp=0xffff880f36b38600 flags=0x46fffff80004080 [521120.726037] INFO: Object 0xffff880f36b38700 @offset=1792 fp=0xffff880f36b38800 [521120.726037] [521120.726974] Bytes b4 ffff880f36b386f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.727898] Object ffff880f36b38700: 00 88 b3 36 0f 88 ff ff 00 00 d8 de 0b 88 ff ff ...6............ [521120.728822] Object ffff880f36b38710: 02 00 00 f0 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.729705] Object ffff880f36b38720: 01 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 ................ [521120.730623] Object ffff880f36b38730: 00 00 00 00 00 00 00 00 01 00 00 00 00 02 00 00 ................ [521120.731621] Object ffff880f36b38740: 00 02 00 00 01 00 00 00 d0 f7 87 ad ff ff ff ff ................ [521120.732776] Object ffff880f36b38750: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.733640] Object ffff880f36b38760: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.734508] Object ffff880f36b38770: 01 00 03 00 01 00 00 00 88 87 b3 36 0f 88 ff ff ...........6.... [521120.735385] Object ffff880f36b38780: 00 73 22 ad 02 88 ff ff 40 13 e0 3c 00 ea ff ff .s".....@..<.... [521120.736667] Object ffff880f36b38790: 00 02 00 00 00 04 00 00 00 00 00 00 00 00 00 00 ................ [521120.737596] Object ffff880f36b387a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.738524] Object ffff880f36b387b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.739388] Object ffff880f36b387c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.740277] Object ffff880f36b387d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.741187] Object ffff880f36b387e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.742233] Object ffff880f36b387f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.743229] CPU: 41 PID: 9644 Comm: mount.ocfs2 Tainted: G B 4.2.0-rc6-next-20150810-sasha-00039-gf909086 #2420 [521120.744274] ffff880f36b38000 ffff880d89c8f638 ffffffffb6e9ba8a ffff880101c0e5c0 [521120.745025] ffff880d89c8f668 ffffffffad76a313 ffff880101c0e5c0 ffffea003cdace00 [521120.745908] ffff880f36b38700 ffff880f36b38798 ffff880d89c8f690 ffffffffad772854 [521120.747063] Call Trace: [521120.747520] dump_stack (lib/dump_stack.c:52) [521120.748053] print_trailer (mm/slub.c:653) [521120.748582] object_err (mm/slub.c:660) [521120.749079] kasan_report_error (include/linux/kasan.h:20 mm/kasan/report.c:152 mm/kasan/report.c:194) [521120.750834] __asan_report_load4_noabort (mm/kasan/report.c:250) [521120.753580] dio_bio_complete (fs/direct-io.c:478) [521120.755752] do_blockdev_direct_IO (fs/direct-io.c:494 fs/direct-io.c:1291) [521120.759765] __blockdev_direct_IO (fs/direct-io.c:1322) [521120.761658] blkdev_direct_IO (fs/block_dev.c:162) [521120.762993] generic_file_read_iter (mm/filemap.c:1738) [521120.767405] blkdev_read_iter (fs/block_dev.c:1649) [521120.768556] __vfs_read (fs/read_write.c:423 fs/read_write.c:434) [521120.772126] vfs_read (fs/read_write.c:454) [521120.773118] SyS_pread64 (fs/read_write.c:607 fs/read_write.c:594) [521120.776062] entry_SYSCALL_64_fastpath (arch/x86/entry/entry_64.S:186) [521120.777375] Memory state around the buggy address: [521120.778118] ffff880f36b38600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.779211] ffff880f36b38680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.780315] >ffff880f36b38700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.781465] ^ [521120.782083] ffff880f36b38780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.783717] ffff880f36b38800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [521120.784818] ================================================================== This patch fixes a few of those places that I caught while auditing the patch, but the original patch should be audited further for more occurences of this issue since I'm not too familiar with the code. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-11 07:05:18 +08:00
if (rw == READ && !error) {
kcryptd_queue_crypt(io);
return;
}
block: don't access bio->bi_error after bio_put() Commit 4246a0b6 ("block: add a bi_error field to struct bio") has added a few dereferences of 'bio' after a call to bio_put(). This causes use-after-frees such as: [521120.719695] BUG: KASan: use after free in dio_bio_complete+0x2b3/0x320 at addr ffff880f36b38714 [521120.720638] Read of size 4 by task mount.ocfs2/9644 [521120.721212] ============================================================================= [521120.722056] BUG kmalloc-256 (Not tainted): kasan: bad access detected [521120.722968] ----------------------------------------------------------------------------- [521120.722968] [521120.723915] Disabling lock debugging due to kernel taint [521120.724539] INFO: Slab 0xffffea003cdace00 objects=32 used=25 fp=0xffff880f36b38600 flags=0x46fffff80004080 [521120.726037] INFO: Object 0xffff880f36b38700 @offset=1792 fp=0xffff880f36b38800 [521120.726037] [521120.726974] Bytes b4 ffff880f36b386f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.727898] Object ffff880f36b38700: 00 88 b3 36 0f 88 ff ff 00 00 d8 de 0b 88 ff ff ...6............ [521120.728822] Object ffff880f36b38710: 02 00 00 f0 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.729705] Object ffff880f36b38720: 01 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 ................ [521120.730623] Object ffff880f36b38730: 00 00 00 00 00 00 00 00 01 00 00 00 00 02 00 00 ................ [521120.731621] Object ffff880f36b38740: 00 02 00 00 01 00 00 00 d0 f7 87 ad ff ff ff ff ................ [521120.732776] Object ffff880f36b38750: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.733640] Object ffff880f36b38760: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.734508] Object ffff880f36b38770: 01 00 03 00 01 00 00 00 88 87 b3 36 0f 88 ff ff ...........6.... [521120.735385] Object ffff880f36b38780: 00 73 22 ad 02 88 ff ff 40 13 e0 3c 00 ea ff ff .s".....@..<.... [521120.736667] Object ffff880f36b38790: 00 02 00 00 00 04 00 00 00 00 00 00 00 00 00 00 ................ [521120.737596] Object ffff880f36b387a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.738524] Object ffff880f36b387b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.739388] Object ffff880f36b387c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.740277] Object ffff880f36b387d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.741187] Object ffff880f36b387e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.742233] Object ffff880f36b387f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [521120.743229] CPU: 41 PID: 9644 Comm: mount.ocfs2 Tainted: G B 4.2.0-rc6-next-20150810-sasha-00039-gf909086 #2420 [521120.744274] ffff880f36b38000 ffff880d89c8f638 ffffffffb6e9ba8a ffff880101c0e5c0 [521120.745025] ffff880d89c8f668 ffffffffad76a313 ffff880101c0e5c0 ffffea003cdace00 [521120.745908] ffff880f36b38700 ffff880f36b38798 ffff880d89c8f690 ffffffffad772854 [521120.747063] Call Trace: [521120.747520] dump_stack (lib/dump_stack.c:52) [521120.748053] print_trailer (mm/slub.c:653) [521120.748582] object_err (mm/slub.c:660) [521120.749079] kasan_report_error (include/linux/kasan.h:20 mm/kasan/report.c:152 mm/kasan/report.c:194) [521120.750834] __asan_report_load4_noabort (mm/kasan/report.c:250) [521120.753580] dio_bio_complete (fs/direct-io.c:478) [521120.755752] do_blockdev_direct_IO (fs/direct-io.c:494 fs/direct-io.c:1291) [521120.759765] __blockdev_direct_IO (fs/direct-io.c:1322) [521120.761658] blkdev_direct_IO (fs/block_dev.c:162) [521120.762993] generic_file_read_iter (mm/filemap.c:1738) [521120.767405] blkdev_read_iter (fs/block_dev.c:1649) [521120.768556] __vfs_read (fs/read_write.c:423 fs/read_write.c:434) [521120.772126] vfs_read (fs/read_write.c:454) [521120.773118] SyS_pread64 (fs/read_write.c:607 fs/read_write.c:594) [521120.776062] entry_SYSCALL_64_fastpath (arch/x86/entry/entry_64.S:186) [521120.777375] Memory state around the buggy address: [521120.778118] ffff880f36b38600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.779211] ffff880f36b38680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.780315] >ffff880f36b38700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.781465] ^ [521120.782083] ffff880f36b38780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [521120.783717] ffff880f36b38800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [521120.784818] ================================================================== This patch fixes a few of those places that I caught while auditing the patch, but the original patch should be audited further for more occurences of this issue since I'm not too familiar with the code. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-11 07:05:18 +08:00
if (unlikely(error))
io->error = error;
crypt_dec_pending(io);
}
static void clone_init(struct dm_crypt_io *io, struct bio *clone)
{
struct crypt_config *cc = io->cc;
clone->bi_private = io;
clone->bi_end_io = crypt_endio;
bio_set_dev(clone, cc->dev->bdev);
clone->bi_opf = io->base_bio->bi_opf;
}
static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
{
struct crypt_config *cc = io->cc;
struct bio *clone;
/*
* We need the original biovec array in order to decrypt
* the whole bio data *afterwards* -- thanks to immutable
* biovecs we don't need to worry about the block layer
* modifying the biovec array; so leverage bio_clone_fast().
*/
clone = bio_clone_fast(io->base_bio, gfp, &cc->bs);
if (!clone)
return 1;
crypt_inc_pending(io);
clone_init(io, clone);
block: Abstract out bvec iterator Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-10-12 06:44:27 +08:00
clone->bi_iter.bi_sector = cc->start + io->sector;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (dm_crypt_integrity_io_alloc(io, clone)) {
crypt_dec_pending(io);
bio_put(clone);
return 1;
}
submit_bio_noacct(clone);
return 0;
}
static void kcryptd_io_read_work(struct work_struct *work)
{
struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
crypt_inc_pending(io);
if (kcryptd_io_read(io, GFP_NOIO))
io->error = BLK_STS_RESOURCE;
crypt_dec_pending(io);
}
static void kcryptd_queue_read(struct dm_crypt_io *io)
{
struct crypt_config *cc = io->cc;
INIT_WORK(&io->work, kcryptd_io_read_work);
queue_work(cc->io_queue, &io->work);
}
static void kcryptd_io_write(struct dm_crypt_io *io)
{
struct bio *clone = io->ctx.bio_out;
submit_bio_noacct(clone);
}
#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
static int dmcrypt_write(void *data)
{
struct crypt_config *cc = data;
struct dm_crypt_io *io;
while (1) {
struct rb_root write_tree;
struct blk_plug plug;
spin_lock_irq(&cc->write_thread_lock);
continue_locked:
if (!RB_EMPTY_ROOT(&cc->write_tree))
goto pop_from_list;
dm crypt: fix crash on exit As the documentation for kthread_stop() says, "if threadfn() may call do_exit() itself, the caller must ensure task_struct can't go away". dm-crypt does not ensure this and therefore crashes when crypt_dtr() calls kthread_stop(). The crash is trivially reproducible by adding a delay before the call to kthread_stop() and just opening and closing a dm-crypt device. general protection fault: 0000 [#1] PREEMPT SMP CPU: 0 PID: 533 Comm: cryptsetup Not tainted 4.8.0-rc7+ #7 task: ffff88003bd0df40 task.stack: ffff8800375b4000 RIP: 0010: kthread_stop+0x52/0x300 Call Trace: crypt_dtr+0x77/0x120 dm_table_destroy+0x6f/0x120 __dm_destroy+0x130/0x250 dm_destroy+0x13/0x20 dev_remove+0xe6/0x120 ? dev_suspend+0x250/0x250 ctl_ioctl+0x1fc/0x530 ? __lock_acquire+0x24f/0x1b10 dm_ctl_ioctl+0x13/0x20 do_vfs_ioctl+0x91/0x6a0 ? ____fput+0xe/0x10 ? entry_SYSCALL_64_fastpath+0x5/0xbd ? trace_hardirqs_on_caller+0x151/0x1e0 SyS_ioctl+0x41/0x70 entry_SYSCALL_64_fastpath+0x1f/0xbd This problem was introduced by bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit"). Looking at the description of that patch (excerpted below), it seems like the problem it addresses can be solved by just using set_current_state instead of __set_current_state, since we obviously need the memory barrier. | dm crypt: fix a possible hang due to race condition on exit | | A kernel thread executes __set_current_state(TASK_INTERRUPTIBLE), | __add_wait_queue, spin_unlock_irq and then tests kthread_should_stop(). | It is possible that the processor reorders memory accesses so that | kthread_should_stop() is executed before __set_current_state(). If | such reordering happens, there is a possible race on thread | termination: [...] So this patch just reverts the aforementioned patch and changes the __set_current_state(TASK_INTERRUPTIBLE) to set_current_state(...). This fixes the crash and should also fix the potential hang. Fixes: bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit") Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-21 22:22:29 +08:00
set_current_state(TASK_INTERRUPTIBLE);
spin_unlock_irq(&cc->write_thread_lock);
dm crypt: fix crash on exit As the documentation for kthread_stop() says, "if threadfn() may call do_exit() itself, the caller must ensure task_struct can't go away". dm-crypt does not ensure this and therefore crashes when crypt_dtr() calls kthread_stop(). The crash is trivially reproducible by adding a delay before the call to kthread_stop() and just opening and closing a dm-crypt device. general protection fault: 0000 [#1] PREEMPT SMP CPU: 0 PID: 533 Comm: cryptsetup Not tainted 4.8.0-rc7+ #7 task: ffff88003bd0df40 task.stack: ffff8800375b4000 RIP: 0010: kthread_stop+0x52/0x300 Call Trace: crypt_dtr+0x77/0x120 dm_table_destroy+0x6f/0x120 __dm_destroy+0x130/0x250 dm_destroy+0x13/0x20 dev_remove+0xe6/0x120 ? dev_suspend+0x250/0x250 ctl_ioctl+0x1fc/0x530 ? __lock_acquire+0x24f/0x1b10 dm_ctl_ioctl+0x13/0x20 do_vfs_ioctl+0x91/0x6a0 ? ____fput+0xe/0x10 ? entry_SYSCALL_64_fastpath+0x5/0xbd ? trace_hardirqs_on_caller+0x151/0x1e0 SyS_ioctl+0x41/0x70 entry_SYSCALL_64_fastpath+0x1f/0xbd This problem was introduced by bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit"). Looking at the description of that patch (excerpted below), it seems like the problem it addresses can be solved by just using set_current_state instead of __set_current_state, since we obviously need the memory barrier. | dm crypt: fix a possible hang due to race condition on exit | | A kernel thread executes __set_current_state(TASK_INTERRUPTIBLE), | __add_wait_queue, spin_unlock_irq and then tests kthread_should_stop(). | It is possible that the processor reorders memory accesses so that | kthread_should_stop() is executed before __set_current_state(). If | such reordering happens, there is a possible race on thread | termination: [...] So this patch just reverts the aforementioned patch and changes the __set_current_state(TASK_INTERRUPTIBLE) to set_current_state(...). This fixes the crash and should also fix the potential hang. Fixes: bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit") Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-21 22:22:29 +08:00
if (unlikely(kthread_should_stop())) {
sched/core: Remove set_task_state() This is a nasty interface and setting the state of a foreign task must not be done. As of the following commit: be628be0956 ("bcache: Make gc wakeup sane, remove set_task_state()") ... everyone in the kernel calls set_task_state() with current, allowing the helper to be removed. However, as the comment indicates, it is still around for those archs where computing current is more expensive than using a pointer, at least in theory. An important arch that is affected is arm64, however this has been addressed now [1] and performance is up to par making no difference with either calls. Of all the callers, if any, it's the locking bits that would care most about this -- ie: we end up passing a tsk pointer to a lot of the lock slowpath, and setting ->state on that. The following numbers are based on two tests: a custom ad-hoc microbenchmark that just measures latencies (for ~65 million calls) between get_task_state() vs get_current_state(). Secondly for a higher overview, an unlink microbenchmark was used, which pounds on a single file with open, close,unlink combos with increasing thread counts (up to 4x ncpus). While the workload is quite unrealistic, it does contend a lot on the inode mutex or now rwsem. [1] https://lkml.kernel.org/r/1483468021-8237-1-git-send-email-mark.rutland@arm.com == 1. x86-64 == Avg runtime set_task_state(): 601 msecs Avg runtime set_current_state(): 552 msecs vanilla dirty Hmean unlink1-processes-2 36089.26 ( 0.00%) 38977.33 ( 8.00%) Hmean unlink1-processes-5 28555.01 ( 0.00%) 29832.55 ( 4.28%) Hmean unlink1-processes-8 37323.75 ( 0.00%) 44974.57 ( 20.50%) Hmean unlink1-processes-12 43571.88 ( 0.00%) 44283.01 ( 1.63%) Hmean unlink1-processes-21 34431.52 ( 0.00%) 38284.45 ( 11.19%) Hmean unlink1-processes-30 34813.26 ( 0.00%) 37975.17 ( 9.08%) Hmean unlink1-processes-48 37048.90 ( 0.00%) 39862.78 ( 7.59%) Hmean unlink1-processes-79 35630.01 ( 0.00%) 36855.30 ( 3.44%) Hmean unlink1-processes-110 36115.85 ( 0.00%) 39843.91 ( 10.32%) Hmean unlink1-processes-141 32546.96 ( 0.00%) 35418.52 ( 8.82%) Hmean unlink1-processes-172 34674.79 ( 0.00%) 36899.21 ( 6.42%) Hmean unlink1-processes-203 37303.11 ( 0.00%) 36393.04 ( -2.44%) Hmean unlink1-processes-224 35712.13 ( 0.00%) 36685.96 ( 2.73%) == 2. ppc64le == Avg runtime set_task_state(): 938 msecs Avg runtime set_current_state: 940 msecs vanilla dirty Hmean unlink1-processes-2 19269.19 ( 0.00%) 30704.50 ( 59.35%) Hmean unlink1-processes-5 20106.15 ( 0.00%) 21804.15 ( 8.45%) Hmean unlink1-processes-8 17496.97 ( 0.00%) 17243.28 ( -1.45%) Hmean unlink1-processes-12 14224.15 ( 0.00%) 17240.21 ( 21.20%) Hmean unlink1-processes-21 14155.66 ( 0.00%) 15681.23 ( 10.78%) Hmean unlink1-processes-30 14450.70 ( 0.00%) 15995.83 ( 10.69%) Hmean unlink1-processes-48 16945.57 ( 0.00%) 16370.42 ( -3.39%) Hmean unlink1-processes-79 15788.39 ( 0.00%) 14639.27 ( -7.28%) Hmean unlink1-processes-110 14268.48 ( 0.00%) 14377.40 ( 0.76%) Hmean unlink1-processes-141 14023.65 ( 0.00%) 16271.69 ( 16.03%) Hmean unlink1-processes-172 13417.62 ( 0.00%) 16067.55 ( 19.75%) Hmean unlink1-processes-203 15293.08 ( 0.00%) 15440.40 ( 0.96%) Hmean unlink1-processes-234 13719.32 ( 0.00%) 16190.74 ( 18.01%) Hmean unlink1-processes-265 16400.97 ( 0.00%) 16115.22 ( -1.74%) Hmean unlink1-processes-296 14388.60 ( 0.00%) 16216.13 ( 12.70%) Hmean unlink1-processes-320 15771.85 ( 0.00%) 15905.96 ( 0.85%) x86-64 (known to be fast for get_current()/this_cpu_read_stable() caching) and ppc64 (with paca) show similar improvements in the unlink microbenches. The small delta for ppc64 (2ms), does not represent the gains on the unlink runs. In the case of x86, there was a decent amount of variation in the latency runs, but always within a 20 to 50ms increase), ppc was more constant. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: mark.rutland@arm.com Link: http://lkml.kernel.org/r/1483479794-14013-5-git-send-email-dave@stgolabs.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-04 05:43:14 +08:00
set_current_state(TASK_RUNNING);
dm crypt: fix crash on exit As the documentation for kthread_stop() says, "if threadfn() may call do_exit() itself, the caller must ensure task_struct can't go away". dm-crypt does not ensure this and therefore crashes when crypt_dtr() calls kthread_stop(). The crash is trivially reproducible by adding a delay before the call to kthread_stop() and just opening and closing a dm-crypt device. general protection fault: 0000 [#1] PREEMPT SMP CPU: 0 PID: 533 Comm: cryptsetup Not tainted 4.8.0-rc7+ #7 task: ffff88003bd0df40 task.stack: ffff8800375b4000 RIP: 0010: kthread_stop+0x52/0x300 Call Trace: crypt_dtr+0x77/0x120 dm_table_destroy+0x6f/0x120 __dm_destroy+0x130/0x250 dm_destroy+0x13/0x20 dev_remove+0xe6/0x120 ? dev_suspend+0x250/0x250 ctl_ioctl+0x1fc/0x530 ? __lock_acquire+0x24f/0x1b10 dm_ctl_ioctl+0x13/0x20 do_vfs_ioctl+0x91/0x6a0 ? ____fput+0xe/0x10 ? entry_SYSCALL_64_fastpath+0x5/0xbd ? trace_hardirqs_on_caller+0x151/0x1e0 SyS_ioctl+0x41/0x70 entry_SYSCALL_64_fastpath+0x1f/0xbd This problem was introduced by bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit"). Looking at the description of that patch (excerpted below), it seems like the problem it addresses can be solved by just using set_current_state instead of __set_current_state, since we obviously need the memory barrier. | dm crypt: fix a possible hang due to race condition on exit | | A kernel thread executes __set_current_state(TASK_INTERRUPTIBLE), | __add_wait_queue, spin_unlock_irq and then tests kthread_should_stop(). | It is possible that the processor reorders memory accesses so that | kthread_should_stop() is executed before __set_current_state(). If | such reordering happens, there is a possible race on thread | termination: [...] So this patch just reverts the aforementioned patch and changes the __set_current_state(TASK_INTERRUPTIBLE) to set_current_state(...). This fixes the crash and should also fix the potential hang. Fixes: bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit") Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-21 22:22:29 +08:00
break;
}
schedule();
sched/core: Remove set_task_state() This is a nasty interface and setting the state of a foreign task must not be done. As of the following commit: be628be0956 ("bcache: Make gc wakeup sane, remove set_task_state()") ... everyone in the kernel calls set_task_state() with current, allowing the helper to be removed. However, as the comment indicates, it is still around for those archs where computing current is more expensive than using a pointer, at least in theory. An important arch that is affected is arm64, however this has been addressed now [1] and performance is up to par making no difference with either calls. Of all the callers, if any, it's the locking bits that would care most about this -- ie: we end up passing a tsk pointer to a lot of the lock slowpath, and setting ->state on that. The following numbers are based on two tests: a custom ad-hoc microbenchmark that just measures latencies (for ~65 million calls) between get_task_state() vs get_current_state(). Secondly for a higher overview, an unlink microbenchmark was used, which pounds on a single file with open, close,unlink combos with increasing thread counts (up to 4x ncpus). While the workload is quite unrealistic, it does contend a lot on the inode mutex or now rwsem. [1] https://lkml.kernel.org/r/1483468021-8237-1-git-send-email-mark.rutland@arm.com == 1. x86-64 == Avg runtime set_task_state(): 601 msecs Avg runtime set_current_state(): 552 msecs vanilla dirty Hmean unlink1-processes-2 36089.26 ( 0.00%) 38977.33 ( 8.00%) Hmean unlink1-processes-5 28555.01 ( 0.00%) 29832.55 ( 4.28%) Hmean unlink1-processes-8 37323.75 ( 0.00%) 44974.57 ( 20.50%) Hmean unlink1-processes-12 43571.88 ( 0.00%) 44283.01 ( 1.63%) Hmean unlink1-processes-21 34431.52 ( 0.00%) 38284.45 ( 11.19%) Hmean unlink1-processes-30 34813.26 ( 0.00%) 37975.17 ( 9.08%) Hmean unlink1-processes-48 37048.90 ( 0.00%) 39862.78 ( 7.59%) Hmean unlink1-processes-79 35630.01 ( 0.00%) 36855.30 ( 3.44%) Hmean unlink1-processes-110 36115.85 ( 0.00%) 39843.91 ( 10.32%) Hmean unlink1-processes-141 32546.96 ( 0.00%) 35418.52 ( 8.82%) Hmean unlink1-processes-172 34674.79 ( 0.00%) 36899.21 ( 6.42%) Hmean unlink1-processes-203 37303.11 ( 0.00%) 36393.04 ( -2.44%) Hmean unlink1-processes-224 35712.13 ( 0.00%) 36685.96 ( 2.73%) == 2. ppc64le == Avg runtime set_task_state(): 938 msecs Avg runtime set_current_state: 940 msecs vanilla dirty Hmean unlink1-processes-2 19269.19 ( 0.00%) 30704.50 ( 59.35%) Hmean unlink1-processes-5 20106.15 ( 0.00%) 21804.15 ( 8.45%) Hmean unlink1-processes-8 17496.97 ( 0.00%) 17243.28 ( -1.45%) Hmean unlink1-processes-12 14224.15 ( 0.00%) 17240.21 ( 21.20%) Hmean unlink1-processes-21 14155.66 ( 0.00%) 15681.23 ( 10.78%) Hmean unlink1-processes-30 14450.70 ( 0.00%) 15995.83 ( 10.69%) Hmean unlink1-processes-48 16945.57 ( 0.00%) 16370.42 ( -3.39%) Hmean unlink1-processes-79 15788.39 ( 0.00%) 14639.27 ( -7.28%) Hmean unlink1-processes-110 14268.48 ( 0.00%) 14377.40 ( 0.76%) Hmean unlink1-processes-141 14023.65 ( 0.00%) 16271.69 ( 16.03%) Hmean unlink1-processes-172 13417.62 ( 0.00%) 16067.55 ( 19.75%) Hmean unlink1-processes-203 15293.08 ( 0.00%) 15440.40 ( 0.96%) Hmean unlink1-processes-234 13719.32 ( 0.00%) 16190.74 ( 18.01%) Hmean unlink1-processes-265 16400.97 ( 0.00%) 16115.22 ( -1.74%) Hmean unlink1-processes-296 14388.60 ( 0.00%) 16216.13 ( 12.70%) Hmean unlink1-processes-320 15771.85 ( 0.00%) 15905.96 ( 0.85%) x86-64 (known to be fast for get_current()/this_cpu_read_stable() caching) and ppc64 (with paca) show similar improvements in the unlink microbenches. The small delta for ppc64 (2ms), does not represent the gains on the unlink runs. In the case of x86, there was a decent amount of variation in the latency runs, but always within a 20 to 50ms increase), ppc was more constant. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: mark.rutland@arm.com Link: http://lkml.kernel.org/r/1483479794-14013-5-git-send-email-dave@stgolabs.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-04 05:43:14 +08:00
set_current_state(TASK_RUNNING);
spin_lock_irq(&cc->write_thread_lock);
goto continue_locked;
pop_from_list:
write_tree = cc->write_tree;
cc->write_tree = RB_ROOT;
spin_unlock_irq(&cc->write_thread_lock);
BUG_ON(rb_parent(write_tree.rb_node));
/*
* Note: we cannot walk the tree here with rb_next because
* the structures may be freed when kcryptd_io_write is called.
*/
blk_start_plug(&plug);
do {
io = crypt_io_from_node(rb_first(&write_tree));
rb_erase(&io->rb_node, &write_tree);
kcryptd_io_write(io);
} while (!RB_EMPTY_ROOT(&write_tree));
blk_finish_plug(&plug);
}
return 0;
}
static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
{
struct bio *clone = io->ctx.bio_out;
struct crypt_config *cc = io->cc;
unsigned long flags;
sector_t sector;
struct rb_node **rbp, *parent;
if (unlikely(io->error)) {
crypt_free_buffer_pages(cc, clone);
bio_put(clone);
crypt_dec_pending(io);
return;
}
/* crypt_convert should have filled the clone bio */
BUG_ON(io->ctx.iter_out.bi_size);
block: Abstract out bvec iterator Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-10-12 06:44:27 +08:00
clone->bi_iter.bi_sector = cc->start + io->sector;
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
submit_bio_noacct(clone);
return;
}
spin_lock_irqsave(&cc->write_thread_lock, flags);
if (RB_EMPTY_ROOT(&cc->write_tree))
wake_up_process(cc->write_thread);
rbp = &cc->write_tree.rb_node;
parent = NULL;
sector = io->sector;
while (*rbp) {
parent = *rbp;
if (sector < crypt_io_from_node(parent)->sector)
rbp = &(*rbp)->rb_left;
else
rbp = &(*rbp)->rb_right;
}
rb_link_node(&io->rb_node, parent, rbp);
rb_insert_color(&io->rb_node, &cc->write_tree);
spin_unlock_irqrestore(&cc->write_thread_lock, flags);
}
static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
struct convert_context *ctx)
{
if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags))
return false;
/*
* Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering
* constraints so they do not need to be issued inline by
* kcryptd_crypt_write_convert().
*/
switch (bio_op(ctx->bio_in)) {
case REQ_OP_WRITE:
case REQ_OP_WRITE_SAME:
case REQ_OP_WRITE_ZEROES:
return true;
default:
return false;
}
}
static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
{
struct crypt_config *cc = io->cc;
struct convert_context *ctx = &io->ctx;
struct bio *clone;
int crypt_finished;
sector_t sector = io->sector;
blk_status_t r;
/*
* Prevent io from disappearing until this function completes.
*/
crypt_inc_pending(io);
crypt_convert_init(cc, ctx, NULL, io->base_bio, sector);
clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
if (unlikely(!clone)) {
io->error = BLK_STS_IOERR;
goto dec;
}
io->ctx.bio_out = clone;
io->ctx.iter_out = clone->bi_iter;
sector += bio_sectors(clone);
crypt_inc_pending(io);
r = crypt_convert(cc, ctx,
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags));
if (r)
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
io->error = r;
crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
/* Wait for completion signaled by kcryptd_async_done() */
wait_for_completion(&ctx->restart);
crypt_finished = 1;
}
/* Encryption was already finished, submit io now */
if (crypt_finished) {
kcryptd_crypt_write_io_submit(io, 0);
io->sector = sector;
}
dec:
crypt_dec_pending(io);
}
static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
{
crypt_dec_pending(io);
}
static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
{
struct crypt_config *cc = io->cc;
blk_status_t r;
crypt_inc_pending(io);
crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
io->sector);
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
r = crypt_convert(cc, &io->ctx,
test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags));
if (r)
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
io->error = r;
if (atomic_dec_and_test(&io->ctx.cc_pending))
kcryptd_crypt_read_done(io);
crypt_dec_pending(io);
}
static void kcryptd_async_done(struct crypto_async_request *async_req,
int error)
{
struct dm_crypt_request *dmreq = async_req->data;
struct convert_context *ctx = dmreq->ctx;
struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
struct crypt_config *cc = io->cc;
/*
* A request from crypto driver backlog is going to be processed now,
* finish the completion and continue in crypt_convert().
* (Callback will be called for the second time for this request.)
*/
Revert "dm crypt: fix deadlock when async crypto algorithm returns -EBUSY" This reverts Linux 4.1-rc1 commit 0618764cb25f6fa9fb31152995de42a8a0496475. The problem which that commit attempts to fix actually lies in the Freescale CAAM crypto driver not dm-crypt. dm-crypt uses CRYPTO_TFM_REQ_MAY_BACKLOG. This means the the crypto driver should internally backlog requests which arrive when the queue is full and process them later. Until the crypto hw's queue becomes full, the driver returns -EINPROGRESS. When the crypto hw's queue if full, the driver returns -EBUSY, and if CRYPTO_TFM_REQ_MAY_BACKLOG is set, is expected to backlog the request and process it when the hardware has queue space. At the point when the driver takes the request from the backlog and starts processing it, it calls the completion function with a status of -EINPROGRESS. The completion function is called (for a second time, in the case of backlogged requests) with a status/err of 0 when a request is done. Crypto drivers for hardware without hardware queueing use the helpers, crypto_init_queue(), crypto_enqueue_request(), crypto_dequeue_request() and crypto_get_backlog() helpers to implement this behaviour correctly, while others implement this behaviour without these helpers (ccp, for example). dm-crypt (before the patch that needs reverting) uses this API correctly. It queues up as many requests as the hw queues will allow (i.e. as long as it gets back -EINPROGRESS from the request function). Then, when it sees at least one backlogged request (gets -EBUSY), it waits till that backlogged request is handled (completion gets called with -EINPROGRESS), and then continues. The references to af_alg_wait_for_completion() and af_alg_complete() in that commit's commit message are irrelevant because those functions only handle one request at a time, unlink dm-crypt. The problem is that the Freescale CAAM driver, which that commit describes as having being tested with, fails to implement the backlogging behaviour correctly. In cam_jr_enqueue(), if the hardware queue is full, it simply returns -EBUSY without backlogging the request. What the observed deadlock was is not described in the commit message but it is obviously the wait_for_completion() in crypto_convert() where dm-crypto would wait for the completion being called with -EINPROGRESS in the case of backlogged requests. This completion will never be completed due to the bug in the CAAM driver. Commit 0618764cb25 incorrectly made dm-crypt wait for every request, even when the driver/hardware queues are not full, which means that dm-crypt will never see -EBUSY. This means that that commit will cause a performance regression on all crypto drivers which implement the API correctly. Revert it. Correct backlog handling should be implemented in the CAAM driver instead. Cc'ing stable purely because commit 0618764cb25 did. If for some reason a stable@ kernel did pick up commit 0618764cb25 it should get reverted. Signed-off-by: Rabin Vincent <rabin.vincent@axis.com> Reviewed-by: Horia Geanta <horia.geanta@freescale.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-05-05 21:15:56 +08:00
if (error == -EINPROGRESS) {
complete(&ctx->restart);
return;
Revert "dm crypt: fix deadlock when async crypto algorithm returns -EBUSY" This reverts Linux 4.1-rc1 commit 0618764cb25f6fa9fb31152995de42a8a0496475. The problem which that commit attempts to fix actually lies in the Freescale CAAM crypto driver not dm-crypt. dm-crypt uses CRYPTO_TFM_REQ_MAY_BACKLOG. This means the the crypto driver should internally backlog requests which arrive when the queue is full and process them later. Until the crypto hw's queue becomes full, the driver returns -EINPROGRESS. When the crypto hw's queue if full, the driver returns -EBUSY, and if CRYPTO_TFM_REQ_MAY_BACKLOG is set, is expected to backlog the request and process it when the hardware has queue space. At the point when the driver takes the request from the backlog and starts processing it, it calls the completion function with a status of -EINPROGRESS. The completion function is called (for a second time, in the case of backlogged requests) with a status/err of 0 when a request is done. Crypto drivers for hardware without hardware queueing use the helpers, crypto_init_queue(), crypto_enqueue_request(), crypto_dequeue_request() and crypto_get_backlog() helpers to implement this behaviour correctly, while others implement this behaviour without these helpers (ccp, for example). dm-crypt (before the patch that needs reverting) uses this API correctly. It queues up as many requests as the hw queues will allow (i.e. as long as it gets back -EINPROGRESS from the request function). Then, when it sees at least one backlogged request (gets -EBUSY), it waits till that backlogged request is handled (completion gets called with -EINPROGRESS), and then continues. The references to af_alg_wait_for_completion() and af_alg_complete() in that commit's commit message are irrelevant because those functions only handle one request at a time, unlink dm-crypt. The problem is that the Freescale CAAM driver, which that commit describes as having being tested with, fails to implement the backlogging behaviour correctly. In cam_jr_enqueue(), if the hardware queue is full, it simply returns -EBUSY without backlogging the request. What the observed deadlock was is not described in the commit message but it is obviously the wait_for_completion() in crypto_convert() where dm-crypto would wait for the completion being called with -EINPROGRESS in the case of backlogged requests. This completion will never be completed due to the bug in the CAAM driver. Commit 0618764cb25 incorrectly made dm-crypt wait for every request, even when the driver/hardware queues are not full, which means that dm-crypt will never see -EBUSY. This means that that commit will cause a performance regression on all crypto drivers which implement the API correctly. Revert it. Correct backlog handling should be implemented in the CAAM driver instead. Cc'ing stable purely because commit 0618764cb25 did. If for some reason a stable@ kernel did pick up commit 0618764cb25 it should get reverted. Signed-off-by: Rabin Vincent <rabin.vincent@axis.com> Reviewed-by: Horia Geanta <horia.geanta@freescale.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-05-05 21:15:56 +08:00
}
if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (error == -EBADMSG) {
char b[BDEVNAME_SIZE];
DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b),
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
(unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)));
io->error = BLK_STS_PROTECTION;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
} else if (error < 0)
io->error = BLK_STS_IOERR;
crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
if (!atomic_dec_and_test(&ctx->cc_pending))
Revert "dm crypt: fix deadlock when async crypto algorithm returns -EBUSY" This reverts Linux 4.1-rc1 commit 0618764cb25f6fa9fb31152995de42a8a0496475. The problem which that commit attempts to fix actually lies in the Freescale CAAM crypto driver not dm-crypt. dm-crypt uses CRYPTO_TFM_REQ_MAY_BACKLOG. This means the the crypto driver should internally backlog requests which arrive when the queue is full and process them later. Until the crypto hw's queue becomes full, the driver returns -EINPROGRESS. When the crypto hw's queue if full, the driver returns -EBUSY, and if CRYPTO_TFM_REQ_MAY_BACKLOG is set, is expected to backlog the request and process it when the hardware has queue space. At the point when the driver takes the request from the backlog and starts processing it, it calls the completion function with a status of -EINPROGRESS. The completion function is called (for a second time, in the case of backlogged requests) with a status/err of 0 when a request is done. Crypto drivers for hardware without hardware queueing use the helpers, crypto_init_queue(), crypto_enqueue_request(), crypto_dequeue_request() and crypto_get_backlog() helpers to implement this behaviour correctly, while others implement this behaviour without these helpers (ccp, for example). dm-crypt (before the patch that needs reverting) uses this API correctly. It queues up as many requests as the hw queues will allow (i.e. as long as it gets back -EINPROGRESS from the request function). Then, when it sees at least one backlogged request (gets -EBUSY), it waits till that backlogged request is handled (completion gets called with -EINPROGRESS), and then continues. The references to af_alg_wait_for_completion() and af_alg_complete() in that commit's commit message are irrelevant because those functions only handle one request at a time, unlink dm-crypt. The problem is that the Freescale CAAM driver, which that commit describes as having being tested with, fails to implement the backlogging behaviour correctly. In cam_jr_enqueue(), if the hardware queue is full, it simply returns -EBUSY without backlogging the request. What the observed deadlock was is not described in the commit message but it is obviously the wait_for_completion() in crypto_convert() where dm-crypto would wait for the completion being called with -EINPROGRESS in the case of backlogged requests. This completion will never be completed due to the bug in the CAAM driver. Commit 0618764cb25 incorrectly made dm-crypt wait for every request, even when the driver/hardware queues are not full, which means that dm-crypt will never see -EBUSY. This means that that commit will cause a performance regression on all crypto drivers which implement the API correctly. Revert it. Correct backlog handling should be implemented in the CAAM driver instead. Cc'ing stable purely because commit 0618764cb25 did. If for some reason a stable@ kernel did pick up commit 0618764cb25 it should get reverted. Signed-off-by: Rabin Vincent <rabin.vincent@axis.com> Reviewed-by: Horia Geanta <horia.geanta@freescale.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-05-05 21:15:56 +08:00
return;
/*
* The request is fully completed: for inline writes, let
* kcryptd_crypt_write_convert() do the IO submission.
*/
if (bio_data_dir(io->base_bio) == READ) {
kcryptd_crypt_read_done(io);
return;
}
if (kcryptd_crypt_write_inline(cc, ctx)) {
complete(&ctx->restart);
return;
}
kcryptd_crypt_write_io_submit(io, 1);
}
static void kcryptd_crypt(struct work_struct *work)
{
struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
if (bio_data_dir(io->base_bio) == READ)
kcryptd_crypt_read_convert(io);
else
kcryptd_crypt_write_convert(io);
}
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
static void kcryptd_crypt_tasklet(unsigned long work)
{
kcryptd_crypt((struct work_struct *)work);
}
static void kcryptd_queue_crypt(struct dm_crypt_io *io)
{
struct crypt_config *cc = io->cc;
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
(bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
if (in_irq()) {
/* Crypto API's "skcipher_walk_first() refuses to work in hard IRQ context */
tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work);
tasklet_schedule(&io->tasklet);
return;
}
kcryptd_crypt(&io->work);
return;
}
INIT_WORK(&io->work, kcryptd_crypt);
queue_work(cc->crypt_queue, &io->work);
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void crypt_free_tfms_aead(struct crypt_config *cc)
{
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (!cc->cipher_tfm.tfms_aead)
return;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
cc->cipher_tfm.tfms_aead[0] = NULL;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
kfree(cc->cipher_tfm.tfms_aead);
cc->cipher_tfm.tfms_aead = NULL;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void crypt_free_tfms_skcipher(struct crypt_config *cc)
{
unsigned i;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (!cc->cipher_tfm.tfms)
return;
for (i = 0; i < cc->tfms_count; i++)
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
cc->cipher_tfm.tfms[i] = NULL;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
kfree(cc->cipher_tfm.tfms);
cc->cipher_tfm.tfms = NULL;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static void crypt_free_tfms(struct crypt_config *cc)
{
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
crypt_free_tfms_aead(cc);
else
crypt_free_tfms_skcipher(cc);
}
static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
{
unsigned i;
int err;
treewide: kzalloc() -> kcalloc() The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-13 05:03:40 +08:00
cc->cipher_tfm.tfms = kcalloc(cc->tfms_count,
sizeof(struct crypto_skcipher *),
GFP_KERNEL);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (!cc->cipher_tfm.tfms)
return -ENOMEM;
for (i = 0; i < cc->tfms_count; i++) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 0);
if (IS_ERR(cc->cipher_tfm.tfms[i])) {
err = PTR_ERR(cc->cipher_tfm.tfms[i]);
crypt_free_tfms(cc);
return err;
}
}
/*
* dm-crypt performance can vary greatly depending on which crypto
* algorithm implementation is used. Help people debug performance
* problems by logging the ->cra_driver_name.
*/
DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name);
return 0;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
{
int err;
cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL);
if (!cc->cipher_tfm.tfms)
return -ENOMEM;
cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 0);
if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
crypt_free_tfms(cc);
return err;
}
DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
return 0;
}
static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
{
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
return crypt_alloc_tfms_aead(cc, ciphermode);
else
return crypt_alloc_tfms_skcipher(cc, ciphermode);
}
static unsigned crypt_subkey_size(struct crypt_config *cc)
{
return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
}
static unsigned crypt_authenckey_size(struct crypt_config *cc)
{
return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
}
/*
* If AEAD is composed like authenc(hmac(sha256),xts(aes)),
* the key must be for some reason in special format.
* This funcion converts cc->key to this special format.
*/
static void crypt_copy_authenckey(char *p, const void *key,
unsigned enckeylen, unsigned authkeylen)
{
struct crypto_authenc_key_param *param;
struct rtattr *rta;
rta = (struct rtattr *)p;
param = RTA_DATA(rta);
param->enckeylen = cpu_to_be32(enckeylen);
rta->rta_len = RTA_LENGTH(sizeof(*param));
rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
p += RTA_SPACE(sizeof(*param));
memcpy(p, key + enckeylen, authkeylen);
p += authkeylen;
memcpy(p, key, enckeylen);
}
static int crypt_setkey(struct crypt_config *cc)
{
unsigned subkey_size;
int err = 0, i, r;
/* Ignore extra keys (which are used for IV etc) */
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
subkey_size = crypt_subkey_size(cc);
if (crypt_integrity_hmac(cc)) {
if (subkey_size < cc->key_mac_size)
return -EINVAL;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
crypt_copy_authenckey(cc->authenc_key, cc->key,
subkey_size - cc->key_mac_size,
cc->key_mac_size);
}
for (i = 0; i < cc->tfms_count; i++) {
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_hmac(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
cc->authenc_key, crypt_authenckey_size(cc));
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
else if (crypt_integrity_aead(cc))
r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
cc->key + (i * subkey_size),
subkey_size);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
else
r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
cc->key + (i * subkey_size),
subkey_size);
if (r)
err = r;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (crypt_integrity_hmac(cc))
memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
return err;
}
#ifdef CONFIG_KEYS
static bool contains_whitespace(const char *str)
{
while (*str)
if (isspace(*str++))
return true;
return false;
}
static int set_key_user(struct crypt_config *cc, struct key *key)
{
const struct user_key_payload *ukp;
ukp = user_key_payload_locked(key);
if (!ukp)
return -EKEYREVOKED;
if (cc->key_size != ukp->datalen)
return -EINVAL;
memcpy(cc->key, ukp->data, cc->key_size);
return 0;
}
#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
static int set_key_encrypted(struct crypt_config *cc, struct key *key)
{
const struct encrypted_key_payload *ekp;
ekp = key->payload.data[0];
if (!ekp)
return -EKEYREVOKED;
if (cc->key_size != ekp->decrypted_datalen)
return -EINVAL;
memcpy(cc->key, ekp->decrypted_data, cc->key_size);
return 0;
}
#endif /* CONFIG_ENCRYPTED_KEYS */
static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
{
char *new_key_string, *key_desc;
int ret;
struct key_type *type;
struct key *key;
int (*set_key)(struct crypt_config *cc, struct key *key);
/*
* Reject key_string with whitespace. dm core currently lacks code for
* proper whitespace escaping in arguments on DM_TABLE_STATUS path.
*/
if (contains_whitespace(key_string)) {
DMERR("whitespace chars not allowed in key string");
return -EINVAL;
}
/* look for next ':' separating key_type from key_description */
key_desc = strpbrk(key_string, ":");
if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
return -EINVAL;
if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) {
type = &key_type_logon;
set_key = set_key_user;
} else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
type = &key_type_user;
set_key = set_key_user;
#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
} else if (!strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
type = &key_type_encrypted;
set_key = set_key_encrypted;
#endif
} else {
return -EINVAL;
}
new_key_string = kstrdup(key_string, GFP_KERNEL);
if (!new_key_string)
return -ENOMEM;
key = request_key(type, key_desc + 1, NULL);
if (IS_ERR(key)) {
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(new_key_string);
return PTR_ERR(key);
}
dm crypt: replace RCU read-side section with rwsem The lockdep splat below hints at a bug in RCU usage in dm-crypt that was introduced with commit c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service"). The kernel keyring function user_key_payload() is in fact a wrapper for rcu_dereference_protected() which must not be called with only rcu_read_lock() section mark. Unfortunately the kernel keyring subsystem doesn't currently provide an interface that allows the use of an RCU read-side section. So for now we must drop RCU in favour of rwsem until a proper function is made available in the kernel keyring subsystem. =============================== [ INFO: suspicious RCU usage. ] 4.10.0-rc5 #2 Not tainted ------------------------------- ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by cryptsetup/6464: #0: (&md->type_lock){+.+.+.}, at: [<ffffffffa02472a2>] dm_lock_md_type+0x12/0x20 [dm_mod] #1: (rcu_read_lock){......}, at: [<ffffffffa02822f8>] crypt_set_key+0x1d8/0x4b0 [dm_crypt] stack backtrace: CPU: 1 PID: 6464 Comm: cryptsetup Not tainted 4.10.0-rc5 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014 Call Trace: dump_stack+0x67/0x92 lockdep_rcu_suspicious+0xc5/0x100 crypt_set_key+0x351/0x4b0 [dm_crypt] ? crypt_set_key+0x1d8/0x4b0 [dm_crypt] crypt_ctr+0x341/0xa53 [dm_crypt] dm_table_add_target+0x147/0x330 [dm_mod] table_load+0x111/0x350 [dm_mod] ? retrieve_status+0x1c0/0x1c0 [dm_mod] ctl_ioctl+0x1f5/0x510 [dm_mod] dm_ctl_ioctl+0xe/0x20 [dm_mod] do_vfs_ioctl+0x8e/0x690 ? ____fput+0x9/0x10 ? task_work_run+0x7e/0xa0 ? trace_hardirqs_on_caller+0x122/0x1b0 SyS_ioctl+0x3c/0x70 entry_SYSCALL_64_fastpath+0x18/0xad RIP: 0033:0x7f392c9a4ec7 RSP: 002b:00007ffef6383378 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffef63830a0 RCX: 00007f392c9a4ec7 RDX: 000000000124fcc0 RSI: 00000000c138fd09 RDI: 0000000000000005 RBP: 00007ffef6383090 R08: 00000000ffffffff R09: 00000000012482b0 R10: 2a28205d34383336 R11: 0000000000000246 R12: 00007f392d803a08 R13: 00007ffef63831e0 R14: 0000000000000000 R15: 00007f392d803a0b Fixes: c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service") Reported-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Ondrej Kozina <okozina@redhat.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-31 22:47:11 +08:00
down_read(&key->sem);
ret = set_key(cc, key);
if (ret < 0) {
dm crypt: replace RCU read-side section with rwsem The lockdep splat below hints at a bug in RCU usage in dm-crypt that was introduced with commit c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service"). The kernel keyring function user_key_payload() is in fact a wrapper for rcu_dereference_protected() which must not be called with only rcu_read_lock() section mark. Unfortunately the kernel keyring subsystem doesn't currently provide an interface that allows the use of an RCU read-side section. So for now we must drop RCU in favour of rwsem until a proper function is made available in the kernel keyring subsystem. =============================== [ INFO: suspicious RCU usage. ] 4.10.0-rc5 #2 Not tainted ------------------------------- ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by cryptsetup/6464: #0: (&md->type_lock){+.+.+.}, at: [<ffffffffa02472a2>] dm_lock_md_type+0x12/0x20 [dm_mod] #1: (rcu_read_lock){......}, at: [<ffffffffa02822f8>] crypt_set_key+0x1d8/0x4b0 [dm_crypt] stack backtrace: CPU: 1 PID: 6464 Comm: cryptsetup Not tainted 4.10.0-rc5 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014 Call Trace: dump_stack+0x67/0x92 lockdep_rcu_suspicious+0xc5/0x100 crypt_set_key+0x351/0x4b0 [dm_crypt] ? crypt_set_key+0x1d8/0x4b0 [dm_crypt] crypt_ctr+0x341/0xa53 [dm_crypt] dm_table_add_target+0x147/0x330 [dm_mod] table_load+0x111/0x350 [dm_mod] ? retrieve_status+0x1c0/0x1c0 [dm_mod] ctl_ioctl+0x1f5/0x510 [dm_mod] dm_ctl_ioctl+0xe/0x20 [dm_mod] do_vfs_ioctl+0x8e/0x690 ? ____fput+0x9/0x10 ? task_work_run+0x7e/0xa0 ? trace_hardirqs_on_caller+0x122/0x1b0 SyS_ioctl+0x3c/0x70 entry_SYSCALL_64_fastpath+0x18/0xad RIP: 0033:0x7f392c9a4ec7 RSP: 002b:00007ffef6383378 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffef63830a0 RCX: 00007f392c9a4ec7 RDX: 000000000124fcc0 RSI: 00000000c138fd09 RDI: 0000000000000005 RBP: 00007ffef6383090 R08: 00000000ffffffff R09: 00000000012482b0 R10: 2a28205d34383336 R11: 0000000000000246 R12: 00007f392d803a08 R13: 00007ffef63831e0 R14: 0000000000000000 R15: 00007f392d803a0b Fixes: c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service") Reported-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Ondrej Kozina <okozina@redhat.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-31 22:47:11 +08:00
up_read(&key->sem);
key_put(key);
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(new_key_string);
return ret;
}
dm crypt: replace RCU read-side section with rwsem The lockdep splat below hints at a bug in RCU usage in dm-crypt that was introduced with commit c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service"). The kernel keyring function user_key_payload() is in fact a wrapper for rcu_dereference_protected() which must not be called with only rcu_read_lock() section mark. Unfortunately the kernel keyring subsystem doesn't currently provide an interface that allows the use of an RCU read-side section. So for now we must drop RCU in favour of rwsem until a proper function is made available in the kernel keyring subsystem. =============================== [ INFO: suspicious RCU usage. ] 4.10.0-rc5 #2 Not tainted ------------------------------- ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by cryptsetup/6464: #0: (&md->type_lock){+.+.+.}, at: [<ffffffffa02472a2>] dm_lock_md_type+0x12/0x20 [dm_mod] #1: (rcu_read_lock){......}, at: [<ffffffffa02822f8>] crypt_set_key+0x1d8/0x4b0 [dm_crypt] stack backtrace: CPU: 1 PID: 6464 Comm: cryptsetup Not tainted 4.10.0-rc5 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-1.fc24 04/01/2014 Call Trace: dump_stack+0x67/0x92 lockdep_rcu_suspicious+0xc5/0x100 crypt_set_key+0x351/0x4b0 [dm_crypt] ? crypt_set_key+0x1d8/0x4b0 [dm_crypt] crypt_ctr+0x341/0xa53 [dm_crypt] dm_table_add_target+0x147/0x330 [dm_mod] table_load+0x111/0x350 [dm_mod] ? retrieve_status+0x1c0/0x1c0 [dm_mod] ctl_ioctl+0x1f5/0x510 [dm_mod] dm_ctl_ioctl+0xe/0x20 [dm_mod] do_vfs_ioctl+0x8e/0x690 ? ____fput+0x9/0x10 ? task_work_run+0x7e/0xa0 ? trace_hardirqs_on_caller+0x122/0x1b0 SyS_ioctl+0x3c/0x70 entry_SYSCALL_64_fastpath+0x18/0xad RIP: 0033:0x7f392c9a4ec7 RSP: 002b:00007ffef6383378 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffef63830a0 RCX: 00007f392c9a4ec7 RDX: 000000000124fcc0 RSI: 00000000c138fd09 RDI: 0000000000000005 RBP: 00007ffef6383090 R08: 00000000ffffffff R09: 00000000012482b0 R10: 2a28205d34383336 R11: 0000000000000246 R12: 00007f392d803a08 R13: 00007ffef63831e0 R14: 0000000000000000 R15: 00007f392d803a0b Fixes: c538f6ec9f56 ("dm crypt: add ability to use keys from the kernel key retention service") Reported-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Ondrej Kozina <okozina@redhat.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-31 22:47:11 +08:00
up_read(&key->sem);
key_put(key);
/* clear the flag since following operations may invalidate previously valid key */
clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
ret = crypt_setkey(cc);
if (!ret) {
set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(cc->key_string);
cc->key_string = new_key_string;
} else
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(new_key_string);
return ret;
}
static int get_key_size(char **key_string)
{
char *colon, dummy;
int ret;
if (*key_string[0] != ':')
return strlen(*key_string) >> 1;
/* look for next ':' in key string */
colon = strpbrk(*key_string + 1, ":");
if (!colon)
return -EINVAL;
if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
return -EINVAL;
*key_string = colon;
/* remaining key string should be :<logon|user>:<key_desc> */
return ret;
}
#else
static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
{
return -EINVAL;
}
static int get_key_size(char **key_string)
{
return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1;
}
#endif /* CONFIG_KEYS */
static int crypt_set_key(struct crypt_config *cc, char *key)
{
int r = -EINVAL;
int key_string_len = strlen(key);
/* Hyphen (which gives a key_size of zero) means there is no key. */
if (!cc->key_size && strcmp(key, "-"))
goto out;
/* ':' means the key is in kernel keyring, short-circuit normal key processing */
if (key[0] == ':') {
r = crypt_set_keyring_key(cc, key + 1);
goto out;
}
/* clear the flag since following operations may invalidate previously valid key */
clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
/* wipe references to any kernel keyring key */
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(cc->key_string);
cc->key_string = NULL;
/* Decode key from its hex representation. */
if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
goto out;
r = crypt_setkey(cc);
if (!r)
set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
out:
/* Hex key string not needed after here, so wipe it. */
memset(key, '0', key_string_len);
return r;
}
static int crypt_wipe_key(struct crypt_config *cc)
{
int r;
clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
get_random_bytes(&cc->key, cc->key_size);
/* Wipe IV private keys */
if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
r = cc->iv_gen_ops->wipe(cc);
if (r)
return r;
}
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(cc->key_string);
cc->key_string = NULL;
r = crypt_setkey(cc);
memset(&cc->key, 0, cc->key_size * sizeof(u8));
return r;
}
static void crypt_calculate_pages_per_client(void)
{
unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
if (!dm_crypt_clients_n)
return;
pages /= dm_crypt_clients_n;
if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT)
pages = DM_CRYPT_MIN_PAGES_PER_CLIENT;
dm_crypt_pages_per_client = pages;
}
static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
{
struct crypt_config *cc = pool_data;
struct page *page;
if (unlikely(percpu_counter_compare(&cc->n_allocated_pages, dm_crypt_pages_per_client) >= 0) &&
likely(gfp_mask & __GFP_NORETRY))
return NULL;
page = alloc_page(gfp_mask);
if (likely(page != NULL))
percpu_counter_add(&cc->n_allocated_pages, 1);
return page;
}
static void crypt_page_free(void *page, void *pool_data)
{
struct crypt_config *cc = pool_data;
__free_page(page);
percpu_counter_sub(&cc->n_allocated_pages, 1);
}
static void crypt_dtr(struct dm_target *ti)
{
struct crypt_config *cc = ti->private;
ti->private = NULL;
if (!cc)
return;
dm crypt: fix crash on exit As the documentation for kthread_stop() says, "if threadfn() may call do_exit() itself, the caller must ensure task_struct can't go away". dm-crypt does not ensure this and therefore crashes when crypt_dtr() calls kthread_stop(). The crash is trivially reproducible by adding a delay before the call to kthread_stop() and just opening and closing a dm-crypt device. general protection fault: 0000 [#1] PREEMPT SMP CPU: 0 PID: 533 Comm: cryptsetup Not tainted 4.8.0-rc7+ #7 task: ffff88003bd0df40 task.stack: ffff8800375b4000 RIP: 0010: kthread_stop+0x52/0x300 Call Trace: crypt_dtr+0x77/0x120 dm_table_destroy+0x6f/0x120 __dm_destroy+0x130/0x250 dm_destroy+0x13/0x20 dev_remove+0xe6/0x120 ? dev_suspend+0x250/0x250 ctl_ioctl+0x1fc/0x530 ? __lock_acquire+0x24f/0x1b10 dm_ctl_ioctl+0x13/0x20 do_vfs_ioctl+0x91/0x6a0 ? ____fput+0xe/0x10 ? entry_SYSCALL_64_fastpath+0x5/0xbd ? trace_hardirqs_on_caller+0x151/0x1e0 SyS_ioctl+0x41/0x70 entry_SYSCALL_64_fastpath+0x1f/0xbd This problem was introduced by bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit"). Looking at the description of that patch (excerpted below), it seems like the problem it addresses can be solved by just using set_current_state instead of __set_current_state, since we obviously need the memory barrier. | dm crypt: fix a possible hang due to race condition on exit | | A kernel thread executes __set_current_state(TASK_INTERRUPTIBLE), | __add_wait_queue, spin_unlock_irq and then tests kthread_should_stop(). | It is possible that the processor reorders memory accesses so that | kthread_should_stop() is executed before __set_current_state(). If | such reordering happens, there is a possible race on thread | termination: [...] So this patch just reverts the aforementioned patch and changes the __set_current_state(TASK_INTERRUPTIBLE) to set_current_state(...). This fixes the crash and should also fix the potential hang. Fixes: bcbd94ff481e ("dm crypt: fix a possible hang due to race condition on exit") Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-09-21 22:22:29 +08:00
if (cc->write_thread)
kthread_stop(cc->write_thread);
if (cc->io_queue)
destroy_workqueue(cc->io_queue);
if (cc->crypt_queue)
destroy_workqueue(cc->crypt_queue);
crypt_free_tfms(cc);
bioset_exit(&cc->bs);
mempool_exit(&cc->page_pool);
mempool_exit(&cc->req_pool);
mempool_exit(&cc->tag_pool);
WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0);
percpu_counter_destroy(&cc->n_allocated_pages);
if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
cc->iv_gen_ops->dtr(cc);
if (cc->dev)
dm_put_device(ti, cc->dev);
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(cc->cipher_string);
kfree_sensitive(cc->key_string);
kfree_sensitive(cc->cipher_auth);
kfree_sensitive(cc->authenc_key);
mutex_destroy(&cc->bio_alloc_lock);
/* Must zero key material before freeing */
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 14:18:13 +08:00
kfree_sensitive(cc);
spin_lock(&dm_crypt_clients_lock);
WARN_ON(!dm_crypt_clients_n);
dm_crypt_clients_n--;
crypt_calculate_pages_per_client();
spin_unlock(&dm_crypt_clients_lock);
}
static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
{
struct crypt_config *cc = ti->private;
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
else
cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
if (cc->iv_size)
/* at least a 64 bit sector number should fit in our buffer */
cc->iv_size = max(cc->iv_size,
(unsigned int)(sizeof(u64) / sizeof(u8)));
else if (ivmode) {
DMWARN("Selected cipher does not support IVs");
ivmode = NULL;
}
/* Choose ivmode, see comments at iv code. */
if (ivmode == NULL)
cc->iv_gen_ops = NULL;
else if (strcmp(ivmode, "plain") == 0)
cc->iv_gen_ops = &crypt_iv_plain_ops;
else if (strcmp(ivmode, "plain64") == 0)
cc->iv_gen_ops = &crypt_iv_plain64_ops;
else if (strcmp(ivmode, "plain64be") == 0)
cc->iv_gen_ops = &crypt_iv_plain64be_ops;
else if (strcmp(ivmode, "essiv") == 0)
cc->iv_gen_ops = &crypt_iv_essiv_ops;
else if (strcmp(ivmode, "benbi") == 0)
cc->iv_gen_ops = &crypt_iv_benbi_ops;
else if (strcmp(ivmode, "null") == 0)
cc->iv_gen_ops = &crypt_iv_null_ops;
else if (strcmp(ivmode, "eboiv") == 0)
cc->iv_gen_ops = &crypt_iv_eboiv_ops;
else if (strcmp(ivmode, "elephant") == 0) {
cc->iv_gen_ops = &crypt_iv_elephant_ops;
cc->key_parts = 2;
cc->key_extra_size = cc->key_size / 2;
if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE)
return -EINVAL;
set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags);
} else if (strcmp(ivmode, "lmk") == 0) {
cc->iv_gen_ops = &crypt_iv_lmk_ops;
/*
* Version 2 and 3 is recognised according
* to length of provided multi-key string.
* If present (version 3), last key is used as IV seed.
* All keys (including IV seed) are always the same size.
*/
if (cc->key_size % cc->key_parts) {
cc->key_parts++;
cc->key_extra_size = cc->key_size / cc->key_parts;
}
} else if (strcmp(ivmode, "tcw") == 0) {
cc->iv_gen_ops = &crypt_iv_tcw_ops;
cc->key_parts += 2; /* IV + whitening */
cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
} else if (strcmp(ivmode, "random") == 0) {
cc->iv_gen_ops = &crypt_iv_random_ops;
/* Need storage space in integrity fields. */
cc->integrity_iv_size = cc->iv_size;
} else {
ti->error = "Invalid IV mode";
return -EINVAL;
}
return 0;
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
/*
* Workaround to parse HMAC algorithm from AEAD crypto API spec.
* The HMAC is needed to calculate tag size (HMAC digest size).
* This should be probably done by crypto-api calls (once available...)
*/
static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
{
char *start, *end, *mac_alg = NULL;
struct crypto_ahash *mac;
if (!strstarts(cipher_api, "authenc("))
return 0;
start = strchr(cipher_api, '(');
end = strchr(cipher_api, ',');
if (!start || !end || ++start > end)
return -EINVAL;
mac_alg = kzalloc(end - start + 1, GFP_KERNEL);
if (!mac_alg)
return -ENOMEM;
strncpy(mac_alg, start, end - start);
mac = crypto_alloc_ahash(mac_alg, 0, 0);
kfree(mac_alg);
if (IS_ERR(mac))
return PTR_ERR(mac);
cc->key_mac_size = crypto_ahash_digestsize(mac);
crypto_free_ahash(mac);
cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
if (!cc->authenc_key)
return -ENOMEM;
return 0;
}
static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
char **ivmode, char **ivopts)
{
struct crypt_config *cc = ti->private;
char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME];
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
int ret = -EINVAL;
cc->tfms_count = 1;
/*
* New format (capi: prefix)
* capi:cipher_api_spec-iv:ivopts
*/
tmp = &cipher_in[strlen("capi:")];
/* Separate IV options if present, it can contain another '-' in hash name */
*ivopts = strrchr(tmp, ':');
if (*ivopts) {
**ivopts = '\0';
(*ivopts)++;
}
/* Parse IV mode */
*ivmode = strrchr(tmp, '-');
if (*ivmode) {
**ivmode = '\0';
(*ivmode)++;
}
/* The rest is crypto API spec */
cipher_api = tmp;
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
/* Alloc AEAD, can be used only in new format. */
if (crypt_integrity_aead(cc)) {
ret = crypt_ctr_auth_cipher(cc, cipher_api);
if (ret < 0) {
ti->error = "Invalid AEAD cipher spec";
return -ENOMEM;
}
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (*ivmode && !strcmp(*ivmode, "lmk"))
cc->tfms_count = 64;
if (*ivmode && !strcmp(*ivmode, "essiv")) {
if (!*ivopts) {
ti->error = "Digest algorithm missing for ESSIV mode";
return -EINVAL;
}
ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)",
cipher_api, *ivopts);
if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
ti->error = "Cannot allocate cipher string";
return -ENOMEM;
}
cipher_api = buf;
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
cc->key_parts = cc->tfms_count;
/* Allocate cipher */
ret = crypt_alloc_tfms(cc, cipher_api);
if (ret < 0) {
ti->error = "Error allocating crypto tfm";
return ret;
}
if (crypt_integrity_aead(cc))
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
else
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
return 0;
}
static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
char **ivmode, char **ivopts)
{
struct crypt_config *cc = ti->private;
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
char *tmp, *cipher, *chainmode, *keycount;
char *cipher_api = NULL;
int ret = -EINVAL;
char dummy;
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
ti->error = "Bad cipher specification";
return -EINVAL;
}
/*
* Legacy dm-crypt cipher specification
* cipher[:keycount]-mode-iv:ivopts
*/
tmp = cipher_in;
keycount = strsep(&tmp, "-");
cipher = strsep(&keycount, ":");
if (!keycount)
cc->tfms_count = 1;
else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
!is_power_of_2(cc->tfms_count)) {
ti->error = "Bad cipher key count specification";
return -EINVAL;
}
cc->key_parts = cc->tfms_count;
chainmode = strsep(&tmp, "-");
*ivmode = strsep(&tmp, ":");
*ivopts = tmp;
/*
* For compatibility with the original dm-crypt mapping format, if
* only the cipher name is supplied, use cbc-plain.
*/
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
chainmode = "cbc";
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
*ivmode = "plain";
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (strcmp(chainmode, "ecb") && !*ivmode) {
ti->error = "IV mechanism required";
return -EINVAL;
}
cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
if (!cipher_api)
goto bad_mem;
if (*ivmode && !strcmp(*ivmode, "essiv")) {
if (!*ivopts) {
ti->error = "Digest algorithm missing for ESSIV mode";
kfree(cipher_api);
return -EINVAL;
}
ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
"essiv(%s(%s),%s)", chainmode, cipher, *ivopts);
} else {
ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
"%s(%s)", chainmode, cipher);
}
if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
kfree(cipher_api);
goto bad_mem;
}
/* Allocate cipher */
ret = crypt_alloc_tfms(cc, cipher_api);
if (ret < 0) {
ti->error = "Error allocating crypto tfm";
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
kfree(cipher_api);
return ret;
}
kfree(cipher_api);
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
return 0;
bad_mem:
ti->error = "Cannot allocate cipher strings";
return -ENOMEM;
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
{
struct crypt_config *cc = ti->private;
char *ivmode = NULL, *ivopts = NULL;
int ret;
cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
if (!cc->cipher_string) {
ti->error = "Cannot allocate cipher strings";
return -ENOMEM;
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (strstarts(cipher_in, "capi:"))
ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
else
ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
if (ret)
return ret;
/* Initialize IV */
ret = crypt_ctr_ivmode(ti, ivmode);
if (ret < 0)
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
return ret;
/* Initialize and set key */
ret = crypt_set_key(cc, key);
if (ret < 0) {
ti->error = "Error decoding and setting key";
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
return ret;
}
/* Allocate IV */
if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
if (ret < 0) {
ti->error = "Error creating IV";
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
return ret;
}
}
/* Initialize IV (set keys for ESSIV etc) */
if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
ret = cc->iv_gen_ops->init(cc);
if (ret < 0) {
ti->error = "Error initialising IV";
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
return ret;
}
}
/* wipe the kernel key payload copy */
if (cc->key_string)
memset(cc->key, 0, cc->key_size * sizeof(u8));
return ret;
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
{
struct crypt_config *cc = ti->private;
struct dm_arg_set as;
static const struct dm_arg _args[] = {
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
{0, 8, "Invalid number of feature args"},
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
};
unsigned int opt_params, val;
const char *opt_string, *sval;
char dummy;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
int ret;
/* Optional parameters */
as.argc = argc;
as.argv = argv;
ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
if (ret)
return ret;
while (opt_params--) {
opt_string = dm_shift_arg(&as);
if (!opt_string) {
ti->error = "Not enough feature arguments";
return -EINVAL;
}
if (!strcasecmp(opt_string, "allow_discards"))
ti->num_discard_bios = 1;
else if (!strcasecmp(opt_string, "same_cpu_crypt"))
set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
else if (!strcasecmp(opt_string, "no_read_workqueue"))
set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
else if (!strcasecmp(opt_string, "no_write_workqueue"))
set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
if (val == 0 || val > MAX_TAG_SIZE) {
ti->error = "Invalid integrity arguments";
return -EINVAL;
}
cc->on_disk_tag_size = val;
sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
if (!strcasecmp(sval, "aead")) {
set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
} else if (strcasecmp(sval, "none")) {
ti->error = "Unknown integrity profile";
return -EINVAL;
}
cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
if (!cc->cipher_auth)
return -ENOMEM;
} else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
if (cc->sector_size < (1 << SECTOR_SHIFT) ||
cc->sector_size > 4096 ||
(cc->sector_size & (cc->sector_size - 1))) {
ti->error = "Invalid feature value for sector_size";
return -EINVAL;
}
if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
ti->error = "Device size is not multiple of sector_size feature";
return -EINVAL;
}
cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
} else if (!strcasecmp(opt_string, "iv_large_sectors"))
set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
else {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
ti->error = "Invalid feature arguments";
return -EINVAL;
}
}
return 0;
}
#ifdef CONFIG_BLK_DEV_ZONED
static int crypt_report_zones(struct dm_target *ti,
struct dm_report_zones_args *args, unsigned int nr_zones)
{
struct crypt_config *cc = ti->private;
sector_t sector = cc->start + dm_target_offset(ti, args->next_sector);
args->start = cc->start;
return blkdev_report_zones(cc->dev->bdev, sector, nr_zones,
dm_report_zones_cb, args);
}
#endif
/*
* Construct an encryption mapping:
* <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
*/
static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
{
struct crypt_config *cc;
const char *devname = dm_table_device_name(ti->table);
int key_size;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
unsigned int align_mask;
unsigned long long tmpll;
int ret;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
size_t iv_size_padding, additional_req_size;
char dummy;
if (argc < 5) {
ti->error = "Not enough arguments";
return -EINVAL;
}
key_size = get_key_size(&argv[1]);
if (key_size < 0) {
ti->error = "Cannot parse key size";
return -EINVAL;
}
cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
if (!cc) {
ti->error = "Cannot allocate encryption context";
return -ENOMEM;
}
cc->key_size = key_size;
cc->sector_size = (1 << SECTOR_SHIFT);
cc->sector_shift = 0;
ti->private = cc;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
spin_lock(&dm_crypt_clients_lock);
dm_crypt_clients_n++;
crypt_calculate_pages_per_client();
spin_unlock(&dm_crypt_clients_lock);
ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL);
if (ret < 0)
goto bad;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/* Optional parameters need to be read before cipher constructor */
if (argc > 5) {
ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
if (ret)
goto bad;
}
ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
if (ret < 0)
goto bad;
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc)) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
cc->dmreq_start = sizeof(struct aead_request);
cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
} else {
cc->dmreq_start = sizeof(struct skcipher_request);
cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
align_mask = crypto_skcipher_alignmask(any_tfm(cc));
}
dm crypt: fix access beyond the end of allocated space The DM crypt target accesses memory beyond allocated space resulting in a crash on 32 bit x86 systems. This bug is very old (it dates back to 2.6.25 commit 3a7f6c990ad04 "dm crypt: use async crypto"). However, this bug was masked by the fact that kmalloc rounds the size up to the next power of two. This bug wasn't exposed until 3.17-rc1 commit 298a9fa08a ("dm crypt: use per-bio data"). By switching to using per-bio data there was no longer any padding beyond the end of a dm-crypt allocated memory block. To minimize allocation overhead dm-crypt puts several structures into one block allocated with kmalloc. The block holds struct ablkcipher_request, cipher-specific scratch pad (crypto_ablkcipher_reqsize(any_tfm(cc))), struct dm_crypt_request and an initialization vector. The variable dmreq_start is set to offset of struct dm_crypt_request within this memory block. dm-crypt allocates the block with this size: cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size. When accessing the initialization vector, dm-crypt uses the function iv_of_dmreq, which performs this calculation: ALIGN((unsigned long)(dmreq + 1), crypto_ablkcipher_alignmask(any_tfm(cc)) + 1). dm-crypt allocated "cc->iv_size" bytes beyond the end of dm_crypt_request structure. However, when dm-crypt accesses the initialization vector, it takes a pointer to the end of dm_crypt_request, aligns it, and then uses it as the initialization vector. If the end of dm_crypt_request is not aligned on a crypto_ablkcipher_alignmask(any_tfm(cc)) boundary the alignment causes the initialization vector to point beyond the allocated space. Fix this bug by calculating the variable iv_size_padding and adding it to the allocated size. Also correct the alignment of dm_crypt_request. struct dm_crypt_request is specific to dm-crypt (it isn't used by the crypto subsystem at all), so it is aligned on __alignof__(struct dm_crypt_request). Also align per_bio_data_size on ARCH_KMALLOC_MINALIGN, so that it is aligned as if the block was allocated with kmalloc. Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Tested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-08-28 23:09:31 +08:00
cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (align_mask < CRYPTO_MINALIGN) {
dm crypt: fix access beyond the end of allocated space The DM crypt target accesses memory beyond allocated space resulting in a crash on 32 bit x86 systems. This bug is very old (it dates back to 2.6.25 commit 3a7f6c990ad04 "dm crypt: use async crypto"). However, this bug was masked by the fact that kmalloc rounds the size up to the next power of two. This bug wasn't exposed until 3.17-rc1 commit 298a9fa08a ("dm crypt: use per-bio data"). By switching to using per-bio data there was no longer any padding beyond the end of a dm-crypt allocated memory block. To minimize allocation overhead dm-crypt puts several structures into one block allocated with kmalloc. The block holds struct ablkcipher_request, cipher-specific scratch pad (crypto_ablkcipher_reqsize(any_tfm(cc))), struct dm_crypt_request and an initialization vector. The variable dmreq_start is set to offset of struct dm_crypt_request within this memory block. dm-crypt allocates the block with this size: cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size. When accessing the initialization vector, dm-crypt uses the function iv_of_dmreq, which performs this calculation: ALIGN((unsigned long)(dmreq + 1), crypto_ablkcipher_alignmask(any_tfm(cc)) + 1). dm-crypt allocated "cc->iv_size" bytes beyond the end of dm_crypt_request structure. However, when dm-crypt accesses the initialization vector, it takes a pointer to the end of dm_crypt_request, aligns it, and then uses it as the initialization vector. If the end of dm_crypt_request is not aligned on a crypto_ablkcipher_alignmask(any_tfm(cc)) boundary the alignment causes the initialization vector to point beyond the allocated space. Fix this bug by calculating the variable iv_size_padding and adding it to the allocated size. Also correct the alignment of dm_crypt_request. struct dm_crypt_request is specific to dm-crypt (it isn't used by the crypto subsystem at all), so it is aligned on __alignof__(struct dm_crypt_request). Also align per_bio_data_size on ARCH_KMALLOC_MINALIGN, so that it is aligned as if the block was allocated with kmalloc. Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Tested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-08-28 23:09:31 +08:00
/* Allocate the padding exactly */
iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
& align_mask;
dm crypt: fix access beyond the end of allocated space The DM crypt target accesses memory beyond allocated space resulting in a crash on 32 bit x86 systems. This bug is very old (it dates back to 2.6.25 commit 3a7f6c990ad04 "dm crypt: use async crypto"). However, this bug was masked by the fact that kmalloc rounds the size up to the next power of two. This bug wasn't exposed until 3.17-rc1 commit 298a9fa08a ("dm crypt: use per-bio data"). By switching to using per-bio data there was no longer any padding beyond the end of a dm-crypt allocated memory block. To minimize allocation overhead dm-crypt puts several structures into one block allocated with kmalloc. The block holds struct ablkcipher_request, cipher-specific scratch pad (crypto_ablkcipher_reqsize(any_tfm(cc))), struct dm_crypt_request and an initialization vector. The variable dmreq_start is set to offset of struct dm_crypt_request within this memory block. dm-crypt allocates the block with this size: cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size. When accessing the initialization vector, dm-crypt uses the function iv_of_dmreq, which performs this calculation: ALIGN((unsigned long)(dmreq + 1), crypto_ablkcipher_alignmask(any_tfm(cc)) + 1). dm-crypt allocated "cc->iv_size" bytes beyond the end of dm_crypt_request structure. However, when dm-crypt accesses the initialization vector, it takes a pointer to the end of dm_crypt_request, aligns it, and then uses it as the initialization vector. If the end of dm_crypt_request is not aligned on a crypto_ablkcipher_alignmask(any_tfm(cc)) boundary the alignment causes the initialization vector to point beyond the allocated space. Fix this bug by calculating the variable iv_size_padding and adding it to the allocated size. Also correct the alignment of dm_crypt_request. struct dm_crypt_request is specific to dm-crypt (it isn't used by the crypto subsystem at all), so it is aligned on __alignof__(struct dm_crypt_request). Also align per_bio_data_size on ARCH_KMALLOC_MINALIGN, so that it is aligned as if the block was allocated with kmalloc. Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Tested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-08-28 23:09:31 +08:00
} else {
/*
* If the cipher requires greater alignment than kmalloc
* alignment, we don't know the exact position of the
* initialization vector. We must assume worst case.
*/
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
iv_size_padding = align_mask;
dm crypt: fix access beyond the end of allocated space The DM crypt target accesses memory beyond allocated space resulting in a crash on 32 bit x86 systems. This bug is very old (it dates back to 2.6.25 commit 3a7f6c990ad04 "dm crypt: use async crypto"). However, this bug was masked by the fact that kmalloc rounds the size up to the next power of two. This bug wasn't exposed until 3.17-rc1 commit 298a9fa08a ("dm crypt: use per-bio data"). By switching to using per-bio data there was no longer any padding beyond the end of a dm-crypt allocated memory block. To minimize allocation overhead dm-crypt puts several structures into one block allocated with kmalloc. The block holds struct ablkcipher_request, cipher-specific scratch pad (crypto_ablkcipher_reqsize(any_tfm(cc))), struct dm_crypt_request and an initialization vector. The variable dmreq_start is set to offset of struct dm_crypt_request within this memory block. dm-crypt allocates the block with this size: cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size. When accessing the initialization vector, dm-crypt uses the function iv_of_dmreq, which performs this calculation: ALIGN((unsigned long)(dmreq + 1), crypto_ablkcipher_alignmask(any_tfm(cc)) + 1). dm-crypt allocated "cc->iv_size" bytes beyond the end of dm_crypt_request structure. However, when dm-crypt accesses the initialization vector, it takes a pointer to the end of dm_crypt_request, aligns it, and then uses it as the initialization vector. If the end of dm_crypt_request is not aligned on a crypto_ablkcipher_alignmask(any_tfm(cc)) boundary the alignment causes the initialization vector to point beyond the allocated space. Fix this bug by calculating the variable iv_size_padding and adding it to the allocated size. Also correct the alignment of dm_crypt_request. struct dm_crypt_request is specific to dm-crypt (it isn't used by the crypto subsystem at all), so it is aligned on __alignof__(struct dm_crypt_request). Also align per_bio_data_size on ARCH_KMALLOC_MINALIGN, so that it is aligned as if the block was allocated with kmalloc. Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Tested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-08-28 23:09:31 +08:00
}
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
/* ...| IV + padding | original IV | original sec. number | bio tag offset | */
additional_req_size = sizeof(struct dm_crypt_request) +
iv_size_padding + cc->iv_size +
cc->iv_size +
sizeof(uint64_t) +
sizeof(unsigned int);
ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size);
if (ret) {
ti->error = "Cannot allocate crypt request mempool";
goto bad;
}
cc->per_bio_data_size = ti->per_io_data_size =
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
dm crypt: fix access beyond the end of allocated space The DM crypt target accesses memory beyond allocated space resulting in a crash on 32 bit x86 systems. This bug is very old (it dates back to 2.6.25 commit 3a7f6c990ad04 "dm crypt: use async crypto"). However, this bug was masked by the fact that kmalloc rounds the size up to the next power of two. This bug wasn't exposed until 3.17-rc1 commit 298a9fa08a ("dm crypt: use per-bio data"). By switching to using per-bio data there was no longer any padding beyond the end of a dm-crypt allocated memory block. To minimize allocation overhead dm-crypt puts several structures into one block allocated with kmalloc. The block holds struct ablkcipher_request, cipher-specific scratch pad (crypto_ablkcipher_reqsize(any_tfm(cc))), struct dm_crypt_request and an initialization vector. The variable dmreq_start is set to offset of struct dm_crypt_request within this memory block. dm-crypt allocates the block with this size: cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size. When accessing the initialization vector, dm-crypt uses the function iv_of_dmreq, which performs this calculation: ALIGN((unsigned long)(dmreq + 1), crypto_ablkcipher_alignmask(any_tfm(cc)) + 1). dm-crypt allocated "cc->iv_size" bytes beyond the end of dm_crypt_request structure. However, when dm-crypt accesses the initialization vector, it takes a pointer to the end of dm_crypt_request, aligns it, and then uses it as the initialization vector. If the end of dm_crypt_request is not aligned on a crypto_ablkcipher_alignmask(any_tfm(cc)) boundary the alignment causes the initialization vector to point beyond the allocated space. Fix this bug by calculating the variable iv_size_padding and adding it to the allocated size. Also correct the alignment of dm_crypt_request. struct dm_crypt_request is specific to dm-crypt (it isn't used by the crypto subsystem at all), so it is aligned on __alignof__(struct dm_crypt_request). Also align per_bio_data_size on ARCH_KMALLOC_MINALIGN, so that it is aligned as if the block was allocated with kmalloc. Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Tested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-08-28 23:09:31 +08:00
ARCH_KMALLOC_MINALIGN);
ret = mempool_init(&cc->page_pool, BIO_MAX_PAGES, crypt_page_alloc, crypt_page_free, cc);
if (ret) {
ti->error = "Cannot allocate page mempool";
goto bad;
}
ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS);
if (ret) {
ti->error = "Cannot allocate crypt bioset";
goto bad;
}
mutex_init(&cc->bio_alloc_lock);
ret = -EINVAL;
if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
(tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
ti->error = "Invalid iv_offset sector";
goto bad;
}
cc->iv_offset = tmpll;
ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
if (ret) {
ti->error = "Device lookup failed";
goto bad;
}
ret = -EINVAL;
if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
ti->error = "Invalid device sector";
goto bad;
}
cc->start = tmpll;
/*
* For zoned block devices, we need to preserve the issuer write
* ordering. To do so, disable write workqueues and force inline
* encryption completion.
*/
if (bdev_is_zoned(cc->dev->bdev)) {
set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags);
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
ret = crypt_integrity_ctr(cc, ti);
if (ret)
goto bad;
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size;
if (!cc->tag_pool_max_sectors)
cc->tag_pool_max_sectors = 1;
ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS,
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
cc->tag_pool_max_sectors * cc->on_disk_tag_size);
if (ret) {
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
ti->error = "Cannot allocate integrity tags mempool";
goto bad;
}
cc->tag_pool_max_sectors <<= cc->sector_shift;
}
ret = -ENOMEM;
cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname);
if (!cc->io_queue) {
ti->error = "Couldn't create kcryptd io queue";
goto bad;
}
if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
1, devname);
else
cc->crypt_queue = alloc_workqueue("kcryptd/%s",
WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
num_online_cpus(), devname);
if (!cc->crypt_queue) {
ti->error = "Couldn't create kcryptd queue";
goto bad;
}
spin_lock_init(&cc->write_thread_lock);
cc->write_tree = RB_ROOT;
cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
if (IS_ERR(cc->write_thread)) {
ret = PTR_ERR(cc->write_thread);
cc->write_thread = NULL;
ti->error = "Couldn't spawn write thread";
goto bad;
}
wake_up_process(cc->write_thread);
ti->num_flush_bios = 1;
return 0;
bad:
crypt_dtr(ti);
return ret;
}
static int crypt_map(struct dm_target *ti, struct bio *bio)
{
struct dm_crypt_io *io;
struct crypt_config *cc = ti->private;
/*
* If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
* - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
* - for REQ_OP_DISCARD caller must use flush if IO ordering matters
*/
if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
bio_op(bio) == REQ_OP_DISCARD)) {
bio_set_dev(bio, cc->dev->bdev);
if (bio_sectors(bio))
block: Abstract out bvec iterator Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-10-12 06:44:27 +08:00
bio->bi_iter.bi_sector = cc->start +
dm_target_offset(ti, bio->bi_iter.bi_sector);
return DM_MAPIO_REMAPPED;
}
/*
* Check if bio is too large, split as needed.
*/
if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) &&
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
(bio_data_dir(bio) == WRITE || cc->on_disk_tag_size))
dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT));
/*
* Ensure that bio is a multiple of internal sector encryption size
* and is aligned to this size as defined in IO hints.
*/
if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
return DM_MAPIO_KILL;
if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
return DM_MAPIO_KILL;
io = dm_per_bio_data(bio, cc->per_bio_data_size);
crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (cc->on_disk_tag_size) {
unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (unlikely(tag_len > KMALLOC_MAX_SIZE) ||
unlikely(!(io->integrity_metadata = kmalloc(tag_len,
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) {
if (bio_sectors(bio) > cc->tag_pool_max_sectors)
dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
io->integrity_metadata_from_pool = true;
}
}
dm crypt: introduce new format of cipher with "capi:" prefix For the new authenticated encryption we have to support generic composed modes (combination of encryption algorithm and authenticator) because this is how the kernel crypto API accesses such algorithms. To simplify the interface, we accept an algorithm directly in crypto API format. The new format is recognised by the "capi:" prefix. The dmcrypt internal IV specification is the same as for the old format. The crypto API cipher specifications format is: capi:cipher_api_spec-ivmode[:ivopts] Examples: capi:cbc(aes)-essiv:sha256 (equivalent to old aes-cbc-essiv:sha256) capi:xts(aes)-plain64 (equivalent to old aes-xts-plain64) Examples of authenticated modes: capi:gcm(aes)-random capi:authenc(hmac(sha256),xts(aes))-random capi:rfc7539(chacha20,poly1305)-random Authenticated modes can only be configured using the new cipher format. Note that this format allows user to specify arbitrary combinations that can be insecure. (Policy decision is done in cryptsetup userspace.) Authenticated encryption algorithms can be of two types, either native modes (like GCM) that performs both encryption and authentication internally, or composed modes where user can compose AEAD with separate specification of encryption algorithm and authenticator. For composed mode with HMAC (length-preserving encryption mode like an XTS and HMAC as an authenticator) we have to calculate HMAC digest size (the separate authentication key is the same size as the HMAC digest). Introduce crypt_ctr_auth_cipher() to parse the crypto API string to get HMAC algorithm and retrieve digest size from it. Also, for HMAC composed mode we need to parse the crypto API string to get the cipher mode nested in the specification. For native AEAD mode (like GCM), we can use crypto_tfm_alg_name() API to get the cipher specification. Because the HMAC composed mode is not processed the same as the native AEAD mode, the CRYPT_MODE_INTEGRITY_HMAC flag is no longer needed and "hmac" specification for the table integrity argument is removed. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-03-16 22:39:40 +08:00
if (crypt_integrity_aead(cc))
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
io->ctx.r.req_aead = (struct aead_request *)(io + 1);
else
io->ctx.r.req = (struct skcipher_request *)(io + 1);
if (bio_data_dir(io->base_bio) == READ) {
if (kcryptd_io_read(io, GFP_NOWAIT))
kcryptd_queue_read(io);
} else
kcryptd_queue_crypt(io);
return DM_MAPIO_SUBMITTED;
}
dm: fix truncated status strings Avoid returning a truncated table or status string instead of setting the DM_BUFFER_FULL_FLAG when the last target of a table fills the buffer. When processing a table or status request, the function retrieve_status calls ti->type->status. If ti->type->status returns non-zero, retrieve_status assumes that the buffer overflowed and sets DM_BUFFER_FULL_FLAG. However, targets don't return non-zero values from their status method on overflow. Most targets returns always zero. If a buffer overflow happens in a target that is not the last in the table, it gets noticed during the next iteration of the loop in retrieve_status; but if a buffer overflow happens in the last target, it goes unnoticed and erroneously truncated data is returned. In the current code, the targets behave in the following way: * dm-crypt returns -ENOMEM if there is not enough space to store the key, but it returns 0 on all other overflows. * dm-thin returns errors from the status method if a disk error happened. This is incorrect because retrieve_status doesn't check the error code, it assumes that all non-zero values mean buffer overflow. * all the other targets always return 0. This patch changes the ti->type->status function to return void (because most targets don't use the return code). Overflow is detected in retrieve_status: if the status method fills up the remaining space completely, it is assumed that buffer overflow happened. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-02 06:45:44 +08:00
static void crypt_status(struct dm_target *ti, status_type_t type,
unsigned status_flags, char *result, unsigned maxlen)
{
struct crypt_config *cc = ti->private;
dm: fix truncated status strings Avoid returning a truncated table or status string instead of setting the DM_BUFFER_FULL_FLAG when the last target of a table fills the buffer. When processing a table or status request, the function retrieve_status calls ti->type->status. If ti->type->status returns non-zero, retrieve_status assumes that the buffer overflowed and sets DM_BUFFER_FULL_FLAG. However, targets don't return non-zero values from their status method on overflow. Most targets returns always zero. If a buffer overflow happens in a target that is not the last in the table, it gets noticed during the next iteration of the loop in retrieve_status; but if a buffer overflow happens in the last target, it goes unnoticed and erroneously truncated data is returned. In the current code, the targets behave in the following way: * dm-crypt returns -ENOMEM if there is not enough space to store the key, but it returns 0 on all other overflows. * dm-thin returns errors from the status method if a disk error happened. This is incorrect because retrieve_status doesn't check the error code, it assumes that all non-zero values mean buffer overflow. * all the other targets always return 0. This patch changes the ti->type->status function to return void (because most targets don't use the return code). Overflow is detected in retrieve_status: if the status method fills up the remaining space completely, it is assumed that buffer overflow happened. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-02 06:45:44 +08:00
unsigned i, sz = 0;
int num_feature_args = 0;
switch (type) {
case STATUSTYPE_INFO:
result[0] = '\0';
break;
case STATUSTYPE_TABLE:
DMEMIT("%s ", cc->cipher_string);
if (cc->key_size > 0) {
if (cc->key_string)
DMEMIT(":%u:%s", cc->key_size, cc->key_string);
else
for (i = 0; i < cc->key_size; i++)
DMEMIT("%02x", cc->key[i]);
} else
dm: fix truncated status strings Avoid returning a truncated table or status string instead of setting the DM_BUFFER_FULL_FLAG when the last target of a table fills the buffer. When processing a table or status request, the function retrieve_status calls ti->type->status. If ti->type->status returns non-zero, retrieve_status assumes that the buffer overflowed and sets DM_BUFFER_FULL_FLAG. However, targets don't return non-zero values from their status method on overflow. Most targets returns always zero. If a buffer overflow happens in a target that is not the last in the table, it gets noticed during the next iteration of the loop in retrieve_status; but if a buffer overflow happens in the last target, it goes unnoticed and erroneously truncated data is returned. In the current code, the targets behave in the following way: * dm-crypt returns -ENOMEM if there is not enough space to store the key, but it returns 0 on all other overflows. * dm-thin returns errors from the status method if a disk error happened. This is incorrect because retrieve_status doesn't check the error code, it assumes that all non-zero values mean buffer overflow. * all the other targets always return 0. This patch changes the ti->type->status function to return void (because most targets don't use the return code). Overflow is detected in retrieve_status: if the status method fills up the remaining space completely, it is assumed that buffer overflow happened. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-02 06:45:44 +08:00
DMEMIT("-");
DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
cc->dev->name, (unsigned long long)cc->start);
num_feature_args += !!ti->num_discard_bios;
num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (cc->on_disk_tag_size)
num_feature_args++;
if (num_feature_args) {
DMEMIT(" %d", num_feature_args);
if (ti->num_discard_bios)
DMEMIT(" allow_discards");
if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
DMEMIT(" same_cpu_crypt");
if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
DMEMIT(" submit_from_crypt_cpus");
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags))
DMEMIT(" no_read_workqueue");
if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))
DMEMIT(" no_write_workqueue");
dm crypt: add cryptographic data integrity protection (authenticated encryption) Allow the use of per-sector metadata, provided by the dm-integrity module, for integrity protection and persistently stored per-sector Initialization Vector (IV). The underlying device must support the "DM-DIF-EXT-TAG" dm-integrity profile. The per-bio integrity metadata is allocated by dm-crypt for every bio. Example of low-level mapping table for various types of use: DEV=/dev/sdb SIZE=417792 # Additional HMAC with CBC-ESSIV, key is concatenated encryption key + HMAC key SIZE_INT=389952 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 32 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-cbc-essiv:sha256 \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:32:hmac(sha256)" # AEAD (Authenticated Encryption with Additional Data) - GCM with random IVs # GCM in kernel uses 96bits IV and we store 128bits auth tag (so 28 bytes metadata space) SIZE_INT=393024 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 28 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-gcm-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:28:aead" # Random IV only for XTS mode (no integrity protection but provides atomic random sector change) SIZE_INT=401272 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 16 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 0 /dev/mapper/x 0 1 integrity:16:none" # Random IV with XTS + HMAC integrity protection SIZE_INT=377656 dmsetup create x --table "0 $SIZE_INT integrity $DEV 0 48 J 0" dmsetup create y --table "0 $SIZE_INT crypt aes-xts-random \ 11ff33c6fb942655efb3e30cf4c0fd95f5ef483afca72166c530ae26151dd83b \ 00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff \ 0 /dev/mapper/x 0 1 integrity:48:hmac(sha256)" Both AEAD and HMAC protection authenticates not only data but also sector metadata. HMAC protection is implemented through autenc wrapper (so it is processed the same way as an authenticated mode). In HMAC mode there are two keys (concatenated in dm-crypt mapping table). First is the encryption key and the second is the key for authentication (HMAC). (It is userspace decision if these keys are independent or somehow derived.) The sector request for AEAD/HMAC authenticated encryption looks like this: |----- AAD -------|------ DATA -------|-- AUTH TAG --| | (authenticated) | (auth+encryption) | | | sector_LE | IV | sector in/out | tag in/out | For writes, the integrity fields are calculated during AEAD encryption of every sector and stored in bio integrity fields and sent to underlying dm-integrity target for storage. For reads, the integrity metadata is verified during AEAD decryption of every sector (they are filled in by dm-integrity, but the integrity fields are pre-allocated in dm-crypt). There is also an experimental support in cryptsetup utility for more friendly configuration (part of LUKS2 format). Because the integrity fields are not valid on initial creation, the device must be "formatted". This can be done by direct-io writes to the device (e.g. dd in direct-io mode). For now, there is available trivial tool to do this, see: https://github.com/mbroz/dm_int_tools Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Vashek Matyas <matyas@fi.muni.cz> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-01-05 03:23:54 +08:00
if (cc->on_disk_tag_size)
DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth);
if (cc->sector_size != (1 << SECTOR_SHIFT))
DMEMIT(" sector_size:%d", cc->sector_size);
if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
DMEMIT(" iv_large_sectors");
}
break;
}
}
static void crypt_postsuspend(struct dm_target *ti)
{
struct crypt_config *cc = ti->private;
set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
}
static int crypt_preresume(struct dm_target *ti)
{
struct crypt_config *cc = ti->private;
if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
DMERR("aborting resume - crypt key is not set.");
return -EAGAIN;
}
return 0;
}
static void crypt_resume(struct dm_target *ti)
{
struct crypt_config *cc = ti->private;
clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
}
/* Message interface
* key set <key>
* key wipe
*/
static int crypt_message(struct dm_target *ti, unsigned argc, char **argv,
char *result, unsigned maxlen)
{
struct crypt_config *cc = ti->private;
int key_size, ret = -EINVAL;
if (argc < 2)
goto error;
if (!strcasecmp(argv[0], "key")) {
if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
DMWARN("not suspended during key manipulation.");
return -EINVAL;
}
if (argc == 3 && !strcasecmp(argv[1], "set")) {
/* The key size may not be changed. */
key_size = get_key_size(&argv[2]);
if (key_size < 0 || cc->key_size != key_size) {
memset(argv[2], '0', strlen(argv[2]));
return -EINVAL;
}
ret = crypt_set_key(cc, argv[2]);
if (ret)
return ret;
if (cc->iv_gen_ops && cc->iv_gen_ops->init)
ret = cc->iv_gen_ops->init(cc);
/* wipe the kernel key payload copy */
if (cc->key_string)
memset(cc->key, 0, cc->key_size * sizeof(u8));
return ret;
}
if (argc == 2 && !strcasecmp(argv[1], "wipe"))
return crypt_wipe_key(cc);
}
error:
DMWARN("unrecognised message received.");
return -EINVAL;
}
static int crypt_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
struct crypt_config *cc = ti->private;
return fn(ti, cc->dev, cc->start, ti->len, data);
}
dm crypt: constrain crypt device's max_segment_size to PAGE_SIZE Setting the dm-crypt device's max_segment_size to PAGE_SIZE is an unfortunate constraint that is required to avoid the potential for exceeding dm-crypt's underlying device's max_segments limits -- due to crypt_alloc_buffer() possibly allocating pages for the encryption bio that are not as physically contiguous as the original bio. It is interesting to note that this problem was already fixed back in 2007 via commit 91e106259 ("dm crypt: use bio_add_page"). But Linux 4.0 commit cf2f1abfb ("dm crypt: don't allocate pages for a partial request") regressed dm-crypt back to _not_ using bio_add_page(). But given dm-crypt's cpu parallelization changes all depend on commit cf2f1abfb's abandoning of the more complex io fragments processing that dm-crypt previously had we cannot easily go back to using bio_add_page(). So all said the cleanest way to resolve this issue is to fix dm-crypt to properly constrain the original bios entering dm-crypt so the encryption bios that dm-crypt generates from the original bios are always compatible with the underlying device's max_segments queue limits. It should be noted that technically Linux 4.3 does _not_ need this fix because of the block core's new late bio-splitting capability. But, it is reasoned, there is little to be gained by having the block core split the encrypted bio that is composed of PAGE_SIZE segments. That said, in the future we may revert this change. Fixes: cf2f1abfb ("dm crypt: don't allocate pages for a partial request") Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=104421 Suggested-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.0+
2015-09-10 09:34:51 +08:00
static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
struct crypt_config *cc = ti->private;
dm crypt: constrain crypt device's max_segment_size to PAGE_SIZE Setting the dm-crypt device's max_segment_size to PAGE_SIZE is an unfortunate constraint that is required to avoid the potential for exceeding dm-crypt's underlying device's max_segments limits -- due to crypt_alloc_buffer() possibly allocating pages for the encryption bio that are not as physically contiguous as the original bio. It is interesting to note that this problem was already fixed back in 2007 via commit 91e106259 ("dm crypt: use bio_add_page"). But Linux 4.0 commit cf2f1abfb ("dm crypt: don't allocate pages for a partial request") regressed dm-crypt back to _not_ using bio_add_page(). But given dm-crypt's cpu parallelization changes all depend on commit cf2f1abfb's abandoning of the more complex io fragments processing that dm-crypt previously had we cannot easily go back to using bio_add_page(). So all said the cleanest way to resolve this issue is to fix dm-crypt to properly constrain the original bios entering dm-crypt so the encryption bios that dm-crypt generates from the original bios are always compatible with the underlying device's max_segments queue limits. It should be noted that technically Linux 4.3 does _not_ need this fix because of the block core's new late bio-splitting capability. But, it is reasoned, there is little to be gained by having the block core split the encrypted bio that is composed of PAGE_SIZE segments. That said, in the future we may revert this change. Fixes: cf2f1abfb ("dm crypt: don't allocate pages for a partial request") Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=104421 Suggested-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.0+
2015-09-10 09:34:51 +08:00
/*
* Unfortunate constraint that is required to avoid the potential
* for exceeding underlying device's max_segments limits -- due to
* crypt_alloc_buffer() possibly allocating pages for the encryption
* bio that are not as physically contiguous as the original bio.
*/
limits->max_segment_size = PAGE_SIZE;
limits->logical_block_size =
max_t(unsigned, limits->logical_block_size, cc->sector_size);
limits->physical_block_size =
max_t(unsigned, limits->physical_block_size, cc->sector_size);
limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size);
dm crypt: constrain crypt device's max_segment_size to PAGE_SIZE Setting the dm-crypt device's max_segment_size to PAGE_SIZE is an unfortunate constraint that is required to avoid the potential for exceeding dm-crypt's underlying device's max_segments limits -- due to crypt_alloc_buffer() possibly allocating pages for the encryption bio that are not as physically contiguous as the original bio. It is interesting to note that this problem was already fixed back in 2007 via commit 91e106259 ("dm crypt: use bio_add_page"). But Linux 4.0 commit cf2f1abfb ("dm crypt: don't allocate pages for a partial request") regressed dm-crypt back to _not_ using bio_add_page(). But given dm-crypt's cpu parallelization changes all depend on commit cf2f1abfb's abandoning of the more complex io fragments processing that dm-crypt previously had we cannot easily go back to using bio_add_page(). So all said the cleanest way to resolve this issue is to fix dm-crypt to properly constrain the original bios entering dm-crypt so the encryption bios that dm-crypt generates from the original bios are always compatible with the underlying device's max_segments queue limits. It should be noted that technically Linux 4.3 does _not_ need this fix because of the block core's new late bio-splitting capability. But, it is reasoned, there is little to be gained by having the block core split the encrypted bio that is composed of PAGE_SIZE segments. That said, in the future we may revert this change. Fixes: cf2f1abfb ("dm crypt: don't allocate pages for a partial request") Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=104421 Suggested-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.0+
2015-09-10 09:34:51 +08:00
}
static struct target_type crypt_target = {
.name = "crypt",
dm crypt: add flags to optionally bypass kcryptd workqueues This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin <ignat@cloudflare.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-07 01:37:31 +08:00
.version = {1, 22, 0},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,
#ifdef CONFIG_BLK_DEV_ZONED
.features = DM_TARGET_ZONED_HM,
.report_zones = crypt_report_zones,
#endif
.map = crypt_map,
.status = crypt_status,
.postsuspend = crypt_postsuspend,
.preresume = crypt_preresume,
.resume = crypt_resume,
.message = crypt_message,
.iterate_devices = crypt_iterate_devices,
dm crypt: constrain crypt device's max_segment_size to PAGE_SIZE Setting the dm-crypt device's max_segment_size to PAGE_SIZE is an unfortunate constraint that is required to avoid the potential for exceeding dm-crypt's underlying device's max_segments limits -- due to crypt_alloc_buffer() possibly allocating pages for the encryption bio that are not as physically contiguous as the original bio. It is interesting to note that this problem was already fixed back in 2007 via commit 91e106259 ("dm crypt: use bio_add_page"). But Linux 4.0 commit cf2f1abfb ("dm crypt: don't allocate pages for a partial request") regressed dm-crypt back to _not_ using bio_add_page(). But given dm-crypt's cpu parallelization changes all depend on commit cf2f1abfb's abandoning of the more complex io fragments processing that dm-crypt previously had we cannot easily go back to using bio_add_page(). So all said the cleanest way to resolve this issue is to fix dm-crypt to properly constrain the original bios entering dm-crypt so the encryption bios that dm-crypt generates from the original bios are always compatible with the underlying device's max_segments queue limits. It should be noted that technically Linux 4.3 does _not_ need this fix because of the block core's new late bio-splitting capability. But, it is reasoned, there is little to be gained by having the block core split the encrypted bio that is composed of PAGE_SIZE segments. That said, in the future we may revert this change. Fixes: cf2f1abfb ("dm crypt: don't allocate pages for a partial request") Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=104421 Suggested-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.0+
2015-09-10 09:34:51 +08:00
.io_hints = crypt_io_hints,
};
static int __init dm_crypt_init(void)
{
int r;
r = dm_register_target(&crypt_target);
if (r < 0)
DMERR("register failed %d", r);
return r;
}
static void __exit dm_crypt_exit(void)
{
dm_unregister_target(&crypt_target);
}
module_init(dm_crypt_init);
module_exit(dm_crypt_exit);
MODULE_AUTHOR("Jana Saout <jana@saout.de>");
MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
MODULE_LICENSE("GPL");