Commit Graph

54 Commits

Author SHA1 Message Date
Eric Biggers 54c1fb39fe X.509: fix comparisons of ->pkey_algo
->pkey_algo used to be an enum, but was changed to a string by commit
4e8ae72a75 ("X.509: Make algo identifiers text instead of enum").  But
two comparisons were not updated.  Fix them to use strcmp().

This bug broke signature verification in certain configurations,
depending on whether the string constants were deduplicated or not.

Fixes: 4e8ae72a75 ("X.509: Make algo identifiers text instead of enum")
Cc: <stable@vger.kernel.org> # v4.6+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-12-08 15:13:29 +00:00
Eric Biggers aa33003620 X.509: use crypto_shash_digest()
Use crypto_shash_digest() instead of crypto_shash_init() followed by
crypto_shash_finup().  (For simplicity only; they are equivalent.)

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-12-08 15:13:29 +00:00
David Howells 1e684d3820 pkcs7: Set the module licence to prevent tainting
Set the module licence to prevent the kernel from being tainted if loaded
as a module.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-15 16:38:45 +00:00
David Howells 436529562d X.509: Allow X.509 certs to be blacklisted
Allow X.509 certs to be blacklisted based on their TBSCertificate hash.
This is convenient since we have to determine this anyway to be able to
check the signature on an X.509 certificate.  This is also what UEFI uses
in its blacklist.

If a certificate built into the kernel is blacklisted, something like the
following might then be seen during boot:

	X.509: Cert 123412341234c55c1dcc601ab8e172917706aa32fb5eaf826813547fdf02dd46 is blacklisted
	Problem loading in-kernel X.509 certificate (-129)

where the hex string shown is the blacklisted hash.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-04-03 16:07:25 +01:00
David Howells a511e1af8b KEYS: Move the point of trust determination to __key_link()
Move the point at which a key is determined to be trustworthy to
__key_link() so that we use the contents of the keyring being linked in to
to determine whether the key being linked in is trusted or not.

What is 'trusted' then becomes a matter of what's in the keyring.

Currently, the test is done when the key is parsed, but given that at that
point we can only sensibly refer to the contents of the system trusted
keyring, we can only use that as the basis for working out the
trustworthiness of a new key.

With this change, a trusted keyring is a set of keys that once the
trusted-only flag is set cannot be added to except by verification through
one of the contained keys.

Further, adding a key into a trusted keyring, whilst it might grant
trustworthiness in the context of that keyring, does not automatically
grant trustworthiness in the context of a second keyring to which it could
be secondarily linked.

To accomplish this, the authentication data associated with the key source
must now be retained.  For an X.509 cert, this means the contents of the
AuthorityKeyIdentifier and the signature data.


If system keyrings are disabled then restrict_link_by_builtin_trusted()
resolves to restrict_link_reject().  The integrity digital signature code
still works correctly with this as it was previously using
KEY_FLAG_TRUSTED_ONLY, which doesn't permit anything to be added if there
is no system keyring against which trust can be determined.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:43:43 +01:00
David Howells cfb664ff2b X.509: Move the trust validation code out to its own file
Move the X.509 trust validation code out to its own file so that it can be
generalised.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:42:55 +01:00
David Howells 5f7f5c81e5 X.509: Use verify_signature() if we have a struct key * to use
We should call verify_signature() rather than directly calling
public_key_verify_signature() if we have a struct key to use as we
shouldn't be poking around in the private data of the key struct as that's
subtype dependent.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:42:27 +01:00
David Howells 9eb029893a KEYS: Generalise x509_request_asymmetric_key()
Generalise x509_request_asymmetric_key().  It doesn't really have any
dependencies on X.509 features as it uses generalised IDs and the
public_key structs that contain data extracted from X.509.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:41:56 +01:00
David Howells 983023f28b KEYS: Move x509_request_asymmetric_key() to asymmetric_type.c
Move x509_request_asymmetric_key() to asymmetric_type.c so that it can be
generalised.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-11 22:41:28 +01:00
David Howells ad3043fda3 X.509: Fix self-signed determination
There's a bug in the code determining whether a certificate is self-signed
or not: if they have neither AKID nor SKID then we just assume that the
cert is self-signed, which may not be true.

Fix this by checking that the raw subject name matches the raw issuer name
and that the public key algorithm for the key and signature are both the
same in addition to requiring that the AKID bits match.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-06 16:13:34 +01:00
David Howells 6c2dc5ae4a X.509: Extract signature digest and make self-signed cert checks earlier
Extract the signature digest for an X.509 certificate earlier, at the end
of x509_cert_parse() rather than leaving it to the callers thereof since it
has to be called anyway.

Further, immediately after that, check the signature on self-signed
certificates, also rather in the callers of x509_cert_parse().

We note in the x509_certificate struct the following bits of information:

 (1) Whether the signature is self-signed (even if we can't check the
     signature due to missing crypto).

 (2) Whether the key held in the certificate needs unsupported crypto to be
     used.  We may get a PKCS#7 message with X.509 certs that we can't make
     use of - we just ignore them and give ENOPKG at the end it we couldn't
     verify anything if at least one of these unusable certs are in the
     chain of trust.

 (3) Whether the signature held in the certificate needs unsupported crypto
     to be checked.  We can still use the key held in this certificate,
     even if we can't check the signature on it - if it is held in the
     system trusted keyring, for instance.  We just can't add it to a ring
     of trusted keys or follow it further up the chain of trust.

Making these checks earlier allows x509_check_signature() to be removed and
replaced with direct calls to public_key_verify_signature().

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-06 16:13:34 +01:00
David Howells 77d0910d15 X.509: Retain the key verification data
Retain the key verification data (ie. the struct public_key_signature)
including the digest and the key identifiers.

Note that this means that we need to take a separate copy of the digest in
x509_get_sig_params() rather than lumping it in with the crypto layer data.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-06 16:13:33 +01:00
David Howells 864e7a816a X.509: Whitespace cleanup
Clean up some whitespace.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-06 16:13:33 +01:00
David Howells 4e8ae72a75 X.509: Make algo identifiers text instead of enum
Make the identifier public key and digest algorithm fields text instead of
enum.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-03-03 21:49:27 +00:00
Tadeusz Struk db6c43bd21 crypto: KEYS: convert public key and digsig asym to the akcipher api
This patch converts the module verification code to the new akcipher API.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David Howells <dhowells@redhat.com>
2016-02-10 10:13:27 +00:00
Petko Manolov 41c89b64d7 IMA: create machine owner and blacklist keyrings
This option creates IMA MOK and blacklist keyrings.  IMA MOK is an
intermediate keyring that sits between .system and .ima keyrings,
effectively forming a simple CA hierarchy.  To successfully import a key
into .ima_mok it must be signed by a key which CA is in .system keyring.
On turn any key that needs to go in .ima keyring must be signed by CA in
either .system or .ima_mok keyrings. IMA MOK is empty at kernel boot.

IMA blacklist keyring contains all revoked IMA keys.  It is consulted
before any other keyring.  If the search is successful the requested
operation is rejected and error is returned to the caller.

Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15 10:01:43 -05:00
Linus Torvalds 1873499e13 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem update from James Morris:
 "This is mostly maintenance updates across the subsystem, with a
  notable update for TPM 2.0, and addition of Jarkko Sakkinen as a
  maintainer of that"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (40 commits)
  apparmor: clarify CRYPTO dependency
  selinux: Use a kmem_cache for allocation struct file_security_struct
  selinux: ioctl_has_perm should be static
  selinux: use sprintf return value
  selinux: use kstrdup() in security_get_bools()
  selinux: use kmemdup in security_sid_to_context_core()
  selinux: remove pointless cast in selinux_inode_setsecurity()
  selinux: introduce security_context_str_to_sid
  selinux: do not check open perm on ftruncate call
  selinux: change CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default
  KEYS: Merge the type-specific data with the payload data
  KEYS: Provide a script to extract a module signature
  KEYS: Provide a script to extract the sys cert list from a vmlinux file
  keys: Be more consistent in selection of union members used
  certs: add .gitignore to stop git nagging about x509_certificate_list
  KEYS: use kvfree() in add_key
  Smack: limited capability for changing process label
  TPM: remove unnecessary little endian conversion
  vTPM: support little endian guests
  char: Drop owner assignment from i2c_driver
  ...
2015-11-05 15:32:38 -08:00
Linus Torvalds ccc9d4a6d6 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "API:

   - Add support for cipher output IVs in testmgr
   - Add missing crypto_ahash_blocksize helper
   - Mark authenc and des ciphers as not allowed under FIPS.

Algorithms:

   - Add CRC support to 842 compression
   - Add keywrap algorithm
   - A number of changes to the akcipher interface:
      + Separate functions for setting public/private keys.
      + Use SG lists.

Drivers:

   - Add Intel SHA Extension optimised SHA1 and SHA256
   - Use dma_map_sg instead of custom functions in crypto drivers
   - Add support for STM32 RNG
   - Add support for ST RNG
   - Add Device Tree support to exynos RNG driver
   - Add support for mxs-dcp crypto device on MX6SL
   - Add xts(aes) support to caam
   - Add ctr(aes) and xts(aes) support to qat
   - A large set of fixes from Russell King for the marvell/cesa driver"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (115 commits)
  crypto: asymmetric_keys - Fix unaligned access in x509_get_sig_params()
  crypto: akcipher - Don't #include crypto/public_key.h as the contents aren't used
  hwrng: exynos - Add Device Tree support
  hwrng: exynos - Fix missing configuration after suspend to RAM
  hwrng: exynos - Add timeout for waiting on init done
  dt-bindings: rng: Describe Exynos4 PRNG bindings
  crypto: marvell/cesa - use __le32 for hardware descriptors
  crypto: marvell/cesa - fix missing cpu_to_le32() in mv_cesa_dma_add_op()
  crypto: marvell/cesa - use memcpy_fromio()/memcpy_toio()
  crypto: marvell/cesa - use gfp_t for gfp flags
  crypto: marvell/cesa - use dma_addr_t for cur_dma
  crypto: marvell/cesa - use readl_relaxed()/writel_relaxed()
  crypto: caam - fix indentation of close braces
  crypto: caam - only export the state we really need to export
  crypto: caam - fix non-block aligned hash calculation
  crypto: caam - avoid needlessly saving and restoring caam_hash_ctx
  crypto: caam - print errno code when hash registration fails
  crypto: marvell/cesa - fix memory leak
  crypto: marvell/cesa - fix first-fragment handling in mv_cesa_ahash_dma_last_req()
  crypto: marvell/cesa - rearrange handling for sw padded hashes
  ...
2015-11-04 09:11:12 -08:00
David Howells 146aa8b145 KEYS: Merge the type-specific data with the payload data
Merge the type-specific data with the payload data into one four-word chunk
as it seems pointless to keep them separate.

Use user_key_payload() for accessing the payloads of overloaded
user-defined keys.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
cc: ecryptfs@vger.kernel.org
cc: linux-ext4@vger.kernel.org
cc: linux-f2fs-devel@lists.sourceforge.net
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-ima-devel@lists.sourceforge.net
2015-10-21 15:18:36 +01:00
Sowmini Varadhan 271817a3e9 crypto: asymmetric_keys - Fix unaligned access in x509_get_sig_params()
x509_get_sig_params() has the same code pattern as the one in
pkcs7_verify() that is fixed by commit 62f57d05e2 ("crypto: pkcs7 - Fix
unaligned access in pkcs7_verify()") so apply a similar fix here: make
sure that desc is pointing at an algined value past the digest_size,
and take alignment values into consideration when doing kzalloc()

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-20 22:14:01 +08:00
David Howells e7c87bef7d X.509: Don't strip leading 00's from key ID when constructing key description
Don't strip leading zeros from the crypto key ID when using it to construct
the struct key description as the signature in kernels up to and including
4.2 matched this aspect of the key.  This means that 1 in 256 keys won't
actually match if their key ID begins with 00.

The key ID is stored in the module signature as binary and so must be
converted to text in order to invoke request_key() - but it isn't stripped
at this point.

Something like this is likely to be observed in dmesg when the key is loaded:

[    1.572423] Loaded X.509 cert 'Build time autogenerated kernel
    key: 62a7c3d2da278be024da4af8652c071f3fea33'

followed by this when we try and use it:

  [    1.646153] Request for unknown module key 'Build time autogenerated
    kernel key: 0062a7c3d2da278be024da4af8652c071f3fea33' err -11

The 'Loaded' line should show an extra '00' on the front of the hex string.

This problem should not affect 4.3-rc1 and onwards because there the key
should be matched on one of its auxiliary identities rather than the key
struct's description string.

Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Reported-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-09-25 16:31:46 +01:00
David Howells fd19a3d195 PKCS#7: Improve and export the X.509 ASN.1 time object decoder
Make the X.509 ASN.1 time object decoder fill in a time64_t rather than a
struct tm to make comparison easier (unfortunately, this makes readable
display less easy) and export it so that it can be used by the PKCS#7 code
too.

Further, tighten up its parsing to reject invalid dates (eg. weird
characters, non-existent hour numbers) and unsupported dates (eg. timezones
other than 'Z' or dates earlier than 1970).

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>
2015-08-12 17:01:01 +01:00
David Howells 4573b64a31 X.509: Support X.509 lookup by Issuer+Serial form AuthorityKeyIdentifier
If an X.509 certificate has an AuthorityKeyIdentifier extension that provides
an issuer and serialNumber, then make it so that these are used in preference
to the keyIdentifier field also held therein for searching for the signing
certificate.

If both the issuer+serialNumber and the keyIdentifier are supplied, then the
certificate is looked up by the former but the latter is checked as well.  If
the latter doesn't match the subjectKeyIdentifier of the parent certificate,
EKEYREJECTED is returned.

This makes it possible to chain X.509 certificates based on the issuer and
serialNumber fields rather than on subjectKeyIdentifier.  This is necessary as
we are having to deal with keys that are represented by X.509 certificates
that lack a subjectKeyIdentifier.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Vivek Goyal <vgoyal@redhat.com>
2015-08-07 16:26:13 +01:00
David Howells b92e6570a9 X.509: Extract both parts of the AuthorityKeyIdentifier
Extract both parts of the AuthorityKeyIdentifier, not just the keyIdentifier,
as the second part can be used to match X.509 certificates by issuer and
serialNumber.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Vivek Goyal <vgoyal@redhat.com>
2015-08-07 16:26:13 +01:00
Mimi Zohar f2b3dee484 KEYS: fix "ca_keys=" partial key matching
The call to asymmetric_key_hex_to_key_id() from ca_keys_setup()
silently fails with -ENOMEM.  Instead of dynamically allocating
memory from a __setup function, this patch defines a variable
and calls __asymmetric_key_hex_to_key_id(), a new helper function,
directly.

This bug was introduced by 'commit 46963b774d ("KEYS: Overhaul
key identification when searching for asymmetric keys")'.

Changelog:
- for clarification, rename hexlen to asciihexlen in
  asymmetric_key_hex_to_key_id()
- add size argument to __asymmetric_key_hex_to_key_id() - David Howells
- inline __asymmetric_key_hex_to_key_id() - David Howells
- remove duplicate strlen() calls

Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 3.18
2015-05-21 13:58:59 -04:00
Dmitry Kasatkin 7a224e783a KEYS: strip 'id:' from ca_keyid
The 'id:' prefix must be stripped for asymmetric_key_hex_to_key_id() to be
able to process ca_keyid.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2014-10-06 17:33:27 +01:00
Dmitry Kasatkin f1b731dbc2 KEYS: Restore partial ID matching functionality for asymmetric keys
Bring back the functionality whereby an asymmetric key can be matched with a
partial match on one of its IDs.

Whilst we're at it, allow for the possibility of having an increased number of
IDs.

Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2014-10-06 15:21:05 +01:00
David Howells dd2f6c4481 X.509: If available, use the raw subjKeyId to form the key description
Module signing matches keys by comparing against the key description exactly.
However, the way the key description gets constructed got changed to be
composed of the subject name plus the certificate serial number instead of the
subject name and the subjectKeyId.  I changed this to avoid problems with
certificates that don't *have* a subjectKeyId.

Instead, if available, use the raw subjectKeyId to form the key description
and only use the serial number if the subjectKeyId doesn't exist.

Reported-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2014-10-03 16:17:02 +01:00
David Howells 4155942000 PKCS#7: Better handling of unsupported crypto
Provide better handling of unsupported crypto when verifying a PKCS#7 message.
If we can't bridge the gap between a pair of X.509 certs or between a signed
info block and an X.509 cert because it involves some crypto we don't support,
that's not necessarily the end of the world as there may be other ways points
at which we can intersect with a ring of trusted keys.

Instead, only produce ENOPKG immediately if all the signed info blocks in a
PKCS#7 message require unsupported crypto to bridge to the first X.509 cert.
Otherwise, we defer the generation of ENOPKG until we get ENOKEY during trust
validation.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-09-16 17:36:15 +01:00
David Howells 46963b774d KEYS: Overhaul key identification when searching for asymmetric keys
Make use of the new match string preparsing to overhaul key identification
when searching for asymmetric keys.  The following changes are made:

 (1) Use the previously created asymmetric_key_id struct to hold the following
     key IDs derived from the X.509 certificate or PKCS#7 message:

	id: serial number + issuer
	skid: subjKeyId + subject
	authority: authKeyId + issuer

 (2) Replace the hex fingerprint attached to key->type_data[1] with an
     asymmetric_key_ids struct containing the id and the skid (if present).

 (3) Make the asymmetric_type match data preparse select one of two searches:

     (a) An iterative search for the key ID given if prefixed with "id:".  The
     	 prefix is expected to be followed by a hex string giving the ID to
     	 search for.  The criterion key ID is checked against all key IDs
     	 recorded on the key.

     (b) A direct search if the key ID is not prefixed with "id:".  This will
     	 look for an exact match on the key description.

 (4) Make x509_request_asymmetric_key() take a key ID.  This is then converted
     into "id:<hex>" and passed into keyring_search() where match preparsing
     will turn it back into a binary ID.

 (5) X.509 certificate verification then takes the authority key ID and looks
     up a key that matches it to find the public key for the certificate
     signature.

 (6) PKCS#7 certificate verification then takes the id key ID and looks up a
     key that matches it to find the public key for the signed information
     block signature.

Additional changes:

 (1) Multiple subjKeyId and authKeyId values on an X.509 certificate cause the
     cert to be rejected with -EBADMSG.

 (2) The 'fingerprint' ID is gone.  This was primarily intended to convey PGP
     public key fingerprints.  If PGP is supported in future, this should
     generate a key ID that carries the fingerprint.

 (3) Th ca_keyid= kernel command line option is now converted to a key ID and
     used to match the authority key ID.  Possibly this should only match the
     actual authKeyId part and not the issuer as well.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-09-16 17:36:13 +01:00
David Howells cf5b50fd2d X.509: Need to export x509_request_asymmetric_key()
Need to export x509_request_asymmetric_key() so that PKCS#7 can use it if
compiled as a module.

Reported-by: James Morris <jmorris@namei.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2014-08-03 12:54:48 +01:00
David Howells 5ce43ad282 PKCS#7: Use x509_request_asymmetric_key()
pkcs7_request_asymmetric_key() and x509_request_asymmetric_key() do the same
thing, the latter being a copy of the former created by the IMA folks, so drop
the PKCS#7 version as the X.509 location is more general.

Whilst we're at it, rename the arguments of x509_request_asymmetric_key() to
better reflect what the values being passed in are intended to match on an
X.509 cert.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-29 13:07:58 +01:00
David Howells 185de09c6a X.509: x509_request_asymmetric_keys() doesn't need string length arguments
x509_request_asymmetric_keys() doesn't need the lengths of the NUL-terminated
strings passing in as it can work that out for itself.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-28 14:55:55 +01:00
David Howells 64724cfc6e Merge remote-tracking branch 'integrity/next-with-keys' into keys-next
Signed-off-by: David Howells <dhowells@redhat.com>
2014-07-22 21:54:43 +01:00
David Howells fc7c70e0b6 KEYS: struct key_preparsed_payload should have two payload pointers
struct key_preparsed_payload should have two payload pointers to correspond
with those in struct key.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Sage Weil <sage@redhat.com>
2014-07-22 21:46:02 +01:00
Dmitry Kasatkin 32c4741cb6 KEYS: validate certificate trust only with builtin keys
Instead of allowing public keys, with certificates signed by any
key on the system trusted keyring, to be added to a trusted keyring,
this patch further restricts the certificates to those signed only by
builtin keys on the system keyring.

This patch defines a new option 'builtin' for the kernel parameter
'keys_ownerid' to allow trust validation using builtin keys.

Simplified Mimi's "KEYS: define an owner trusted keyring" patch

Changelog v7:
- rename builtin_keys to use_builtin_keys

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:17 -04:00
Dmitry Kasatkin ffb70f61ba KEYS: validate certificate trust only with selected key
Instead of allowing public keys, with certificates signed by any
key on the system trusted keyring, to be added to a trusted keyring,
this patch further restricts the certificates to those signed by a
particular key on the system keyring.

This patch defines a new kernel parameter 'ca_keys' to identify the
specific key which must be used for trust validation of certificates.

Simplified Mimi's "KEYS: define an owner trusted keyring" patch.

Changelog:
- support for builtin x509 public keys only
- export "asymmetric_keyid_match"
- remove ifndefs MODULE
- rename kernel boot parameter from keys_ownerid to ca_keys

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17 09:35:16 -04:00
Mimi Zohar 3be4beaf7c KEYS: verify a certificate is signed by a 'trusted' key
Only public keys, with certificates signed by an existing
'trusted' key on the system trusted keyring, should be added
to a trusted keyring.  This patch adds support for verifying
a certificate's signature.

This is derived from David Howells pkcs7_request_asymmetric_key() patch.

Changelog v6:
- on error free key - Dmitry
- validate trust only for not already trusted keys - Dmitry
- formatting cleanup

Changelog:
- define get_system_trusted_keyring() to fix kbuild issues

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
2014-07-17 09:35:15 -04:00
Linus Torvalds 4c1cc40a2d Revert "KEYS: verify a certificate is signed by a 'trusted' key"
This reverts commit 09fbc47373, which
caused the following build errors:

  crypto/asymmetric_keys/x509_public_key.c: In function ‘x509_key_preparse’:
  crypto/asymmetric_keys/x509_public_key.c:237:35: error: ‘system_trusted_keyring’ undeclared (first use in this function)
   ret = x509_validate_trust(cert, system_trusted_keyring);
                                   ^
  crypto/asymmetric_keys/x509_public_key.c:237:35: note: each undeclared identifier is reported only once for each function it appears in

reported by Jim Davis. Mimi says:

 "I made the classic mistake of requesting this patch to be upstreamed
  at the last second, rather than waiting until the next open window.

  At this point, the best course would probably be to revert the two
  commits and fix them for the next open window"

Reported-by: Jim Davis <jim.epost@gmail.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-23 16:38:17 -08:00
Dmitry Kasatkin c7c8bb237f ima: provide support for arbitrary hash algorithms
In preparation of supporting more hash algorithms with larger hash sizes
needed for signature verification, this patch replaces the 20 byte sized
digest, with a more flexible structure.  The new structure includes the
hash algorithm, digest size, and digest.

Changelog:
- recalculate filedata hash for the measurement list, if the signature
  hash digest size is greater than 20 bytes.
- use generic HASH_ALGO_
- make ima_calc_file_hash static
- scripts lindent and checkpatch fixes

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-10-25 17:16:58 -04:00
Dmitry Kasatkin 3fe78ca2fb keys: change asymmetric keys to use common hash definitions
This patch makes use of the newly defined common hash algorithm info,
replacing, for example, PKEY_HASH with HASH_ALGO.

Changelog:
- Lindent fixes - Mimi

CC: David Howells <dhowells@redhat.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-10-25 17:15:18 -04:00
Konstantin Khlebnikov e19aaa7d43 X.509: add module description and license
This patch fixes lack of license, otherwise x509_key_parser.ko taints kernel.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
Mimi Zohar 09fbc47373 KEYS: verify a certificate is signed by a 'trusted' key
Only public keys, with certificates signed by an existing
'trusted' key on the system trusted keyring, should be added
to a trusted keyring.  This patch adds support for verifying
a certificate's signature.

This is derived from David Howells pkcs7_request_asymmetric_key() patch.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
David Howells 124df92609 X.509: Remove certificate date checks
Remove the certificate date checks that are performed when a certificate is
parsed.  There are two checks: a valid from and a valid to.  The first check is
causing a lot of problems with system clocks that don't keep good time and the
second places an implicit expiry date upon the kernel when used for module
signing, so do we really need them?

Signed-off-by: David Howells <dhowells@redhat.com>
cc: David Woodhouse <dwmw2@infradead.org>
cc: Rusty Russell <rusty@rustcorp.com.au>
cc: Josh Boyer <jwboyer@redhat.com>
cc: Alexander Holler <holler@ahsoftware.de>
cc: stable@vger.kernel.org
2013-09-25 17:17:01 +01:00
David Howells 17334cabc8 X.509: Handle certificates that lack an authorityKeyIdentifier field
Handle certificates that lack an authorityKeyIdentifier field by assuming
they're self-signed and checking their signatures against themselves.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:01 +01:00
David Howells 2ecdb23b8c X.509: Check the algorithm IDs obtained from parsing an X.509 certificate
Check that the algorithm IDs obtained from the ASN.1 parse by OID lookup
corresponds to algorithms that are available to us.

Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-25 17:17:01 +01:00
David Howells b426beb6ee X.509: Embed public_key_signature struct and create filler function
Embed a public_key_signature struct in struct x509_certificate, eliminating
now unnecessary fields, and split x509_check_signature() to create a filler
function for it that attaches a digest of the signed data and an MPI that
represents the signature data.  x509_free_certificate() is then modified to
deal with these.

Whilst we're at it, export both x509_check_signature() and the new
x509_get_sig_params().

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:00 +01:00
David Howells 3d167d68e3 KEYS: Split public_key_verify_signature() and make available
Modify public_key_verify_signature() so that it now takes a public_key struct
rather than a key struct and supply a wrapper that takes a key struct.  The
wrapper is then used by the asymmetric key subtype and the modified function is
used by X.509 self-signature checking and can be used by other things also.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:00 +01:00
David Howells 67f7d60b3a KEYS: Store public key algo ID in public_key struct
Store public key algo ID in public_key struct for reference purposes.  This
allows it to be removed from the x509_certificate struct and used to find a
default in public_key_verify_signature().

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 17:17:00 +01:00
David Howells 206ce59a10 KEYS: Move the algorithm pointer array from x509 to public_key.c
Move the public-key algorithm pointer array from x509_public_key.c to
public_key.c as it isn't X.509 specific.

Note that to make this configure correctly, the public key part must be
dependent on the RSA module rather than the other way round.  This needs a
further patch to make use of the crypto module loading stuff rather than using
a fixed table.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
2013-09-25 15:51:07 +01:00