Commit Graph

314 Commits

Author SHA1 Message Date
Szymon Janc 64e759f58f Bluetooth: Fix missing encryption refresh on Security Request
If Security Request is received on connection that is already encrypted
with sufficient security master should perform encryption key refresh
procedure instead of just ignoring Slave Security Request
(Core Spec 5.0 Vol 3 Part H 2.4.6).

> ACL Data RX: Handle 3585 flags 0x02 dlen 6
      SMP: Security Request (0x0b) len 1
        Authentication requirement: Bonding, No MITM, SC, No Keypresses (0x09)
< HCI Command: LE Start Encryption (0x08|0x0019) plen 28
        Handle: 3585
        Random number: 0x0000000000000000
        Encrypted diversifier: 0x0000
        Long term key: 44264272a5c426a9e868f034cf0e69f3
> HCI Event: Command Status (0x0f) plen 4
      LE Start Encryption (0x08|0x0019) ncmd 1
        Status: Success (0x00)
> HCI Event: Encryption Key Refresh Complete (0x30) plen 3
        Status: Success (0x00)
        Handle: 3585

Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2018-03-01 19:55:56 +01:00
Marcel Holtmann 2064ee332e Bluetooth: Use bt_dev_err and bt_dev_info when possible
In case of using BT_ERR and BT_INFO, convert to bt_dev_err and
bt_dev_info when possible. This allows for controller specific
reporting.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2017-10-30 12:25:45 +02:00
Tudor Ambarus c0153b0b90 Bluetooth: let the crypto subsystem generate the ecc privkey
That Bluetooth SMP knows about the private key is pointless, since the
detection of debug key usage is actually via the public key portion.
With this patch, the Bluetooth SMP will stop keeping a copy of the
ecdh private key and will let the crypto subsystem to generate and
handle the ecdh private key, potentially benefiting of hardware
ecc private key generation and retention.

The loop that tries to generate a correct private key is now removed and
we trust the crypto subsystem to generate a correct private key. This
backup logic should be done in crypto, if really needed.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-10-06 20:35:47 +02:00
Tudor Ambarus a297641610 Bluetooth: ecdh_helper - reveal error codes
ecdh_helper functions were hiding the error codes and chose to return
the return value of an relational operator, "==". Remove the unnecessary
query and reveal the error codes.

While updating the return values, code in a way that compilers will
warn in case of uninitialized err.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-10-06 20:35:47 +02:00
Tudor Ambarus 47eb2ac809 Bluetooth: move ecdh allocation outside of ecdh_helper
Before this change, a new crypto tfm was allocated, each time,
for both key generation and shared secret computation.

Allocate a single tfm for both cases.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-10-06 20:35:47 +02:00
Jason A. Donenfeld 329d823098 Bluetooth: use constant time memory comparison for secret values
This file is filled with complex cryptography. Thus, the comparisons of
MACs and secret keys and curve points and so forth should not add timing
attacks, which could either result in a direct forgery, or, given the
complexity, some other type of attack.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
2017-06-10 15:45:40 +02:00
Marcel Holtmann 71653eb64b Bluetooth: Add selftest for ECDH key generation
Since the ECDH key generation takes a different path, it needs to be
tested as well. For this generate the public debug key from the private
debug key and compare both.

This also moves the seeding of the private key into the SMP calling code
to allow for easier re-use of the ECDH key generation helper.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2017-04-30 16:52:43 +03:00
Salvatore Benedetto 58771c1cb0 Bluetooth: convert smp and selftest to crypto kpp API
* Convert both smp and selftest to crypto kpp API
* Remove module ecc as no more required
* Add ecdh_helper functions for wrapping kpp async calls

This patch has been tested *only* with selftest, which is called on
module loading.

Signed-off-by: Salvatore Benedetto <salvatore.benedetto@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2017-04-25 04:53:42 +02:00
Johan Hedberg a62da6f14d Bluetooth: SMP: Add support for H7 crypto function and CT2 auth flag
Bluetooth 5.0 introduces a new H7 key generation function that's used
when both sides of the pairing set the CT2 authentication flag to 1.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-12-08 07:50:24 +01:00
Szymon Janc 83ebb9ec73 Bluetooth: Fix not registering BR/EDR SMP channel with force_bredr flag
If force_bredr is set SMP BR/EDR channel should also be for non-SC
capable controllers. Since hcidev flag is persistent wrt power toggle
it can be already set when calling smp_register(). This resulted in
SMP BR/EDR channel not being registered even if HCI_FORCE_BREDR_SMP
flag was set.

This also fix NULL pointer dereference when trying to disable
force_bredr after power cycle.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000388
IP: [<ffffffffc0493ad8>] smp_del_chan+0x18/0x80 [bluetooth]

Call Trace:
[<ffffffffc04950ca>] force_bredr_smp_write+0xba/0x100 [bluetooth]
[<ffffffff8133be14>] full_proxy_write+0x54/0x90
[<ffffffff81245967>] __vfs_write+0x37/0x160
[<ffffffff813617f7>] ? selinux_file_permission+0xd7/0x110
[<ffffffff81356fbd>] ? security_file_permission+0x3d/0xc0
[<ffffffff810eb5b2>] ? percpu_down_read+0x12/0x50
[<ffffffff812462a5>] vfs_write+0xb5/0x1a0
[<ffffffff812476f5>] SyS_write+0x55/0xc0
[<ffffffff817eb872>] entry_SYSCALL_64_fastpath+0x1a/0xa4
Code: 48 8b 45 f0 eb c1 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f
      44 00 00 f6 05 c6 3b 02 00 04 55 48 89 e5 41 54 53 49 89 fc 75
      4b
      <49> 8b 9c 24 88 03 00 00 48 85 db 74 31 49 c7 84 24 88 03 00 00
RIP  [<ffffffffc0493ad8>] smp_del_chan+0x18/0x80 [bluetooth]
RSP <ffff8802aee3bd90>
CR2: 0000000000000388

Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-09-19 20:19:34 +02:00
Andy Lutomirski a4770e1117 Bluetooth: Switch SMP to crypto_cipher_encrypt_one()
SMP does ECB crypto on stack buffers.  This is complicated and
fragile, and it will not work if the stack is virtually allocated.

Switch to the crypto_cipher interface, which is simpler and safer.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-07-08 12:20:57 +02:00
Linus Torvalds 70477371dc Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "Here is the crypto update for 4.6:

  API:
   - Convert remaining crypto_hash users to shash or ahash, also convert
     blkcipher/ablkcipher users to skcipher.
   - Remove crypto_hash interface.
   - Remove crypto_pcomp interface.
   - Add crypto engine for async cipher drivers.
   - Add akcipher documentation.
   - Add skcipher documentation.

  Algorithms:
   - Rename crypto/crc32 to avoid name clash with lib/crc32.
   - Fix bug in keywrap where we zero the wrong pointer.

  Drivers:
   - Support T5/M5, T7/M7 SPARC CPUs in n2 hwrng driver.
   - Add PIC32 hwrng driver.
   - Support BCM6368 in bcm63xx hwrng driver.
   - Pack structs for 32-bit compat users in qat.
   - Use crypto engine in omap-aes.
   - Add support for sama5d2x SoCs in atmel-sha.
   - Make atmel-sha available again.
   - Make sahara hashing available again.
   - Make ccp hashing available again.
   - Make sha1-mb available again.
   - Add support for multiple devices in ccp.
   - Improve DMA performance in caam.
   - Add hashing support to rockchip"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (116 commits)
  crypto: qat - remove redundant arbiter configuration
  crypto: ux500 - fix checks of error code returned by devm_ioremap_resource()
  crypto: atmel - fix checks of error code returned by devm_ioremap_resource()
  crypto: qat - Change the definition of icp_qat_uof_regtype
  hwrng: exynos - use __maybe_unused to hide pm functions
  crypto: ccp - Add abstraction for device-specific calls
  crypto: ccp - CCP versioning support
  crypto: ccp - Support for multiple CCPs
  crypto: ccp - Remove check for x86 family and model
  crypto: ccp - memset request context to zero during import
  lib/mpi: use "static inline" instead of "extern inline"
  lib/mpi: avoid assembler warning
  hwrng: bcm63xx - fix non device tree compatibility
  crypto: testmgr - allow rfc3686 aes-ctr variants in fips mode.
  crypto: qat - The AE id should be less than the maximal AE number
  lib/mpi: Endianness fix
  crypto: rockchip - add hash support for crypto engine in rk3288
  crypto: xts - fix compile errors
  crypto: doc - add skcipher API documentation
  crypto: doc - update AEAD AD handling
  ...
2016-03-17 11:22:54 -07:00
Johan Hedberg cff10ce7b4 Bluetooth: Fix incorrect removing of IRKs
The commit cad20c2780 was supposed to
fix handling of devices first using public addresses and then
switching to RPAs after pairing. Unfortunately it missed a couple of
key places in the code.

1. When evaluating which devices should be removed from the existing
white list we also need to consider whether we have an IRK for them or
not, i.e. a call to hci_find_irk_by_addr() is needed.

2. In smp_notify_keys() we should not be requiring the knowledge of
the RPA, but should simply keep the IRK around if the other conditions
require it.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.4+
2016-01-29 11:47:24 +01:00
Herbert Xu 71af2f6bb2 Bluetooth: Use skcipher and hash
This patch replaces uses of blkcipher with skcipher and the long
obsolete hash interface with shash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
2016-01-27 20:36:04 +08:00
Johan Hedberg 7883746bc6 Bluetooth: Fix l2cap_chan leak in SMP
The L2CAP core expects channel implementations to manage the reference
returned by the new_connection callback. With sockets this is already
handled with each channel being tied to the corresponding socket. With
SMP however there's no context to tie the pointer to in the
smp_new_conn_cb function. The function can also not just drop the
reference since it's the only one at that point.

For fixed channels (like SMP) the code path inside the L2CAP core from
new_connection() to ready() is short and straight-forwards. The
crucial difference is that in ready() the implementation has access to
the l2cap_conn that SMP needs associate its l2cap_chan. Instead of
taking a new reference in smp_ready_cb() we can simply assume to
already own the reference created in smp_new_conn_cb(), i.e. there is
no need to call l2cap_chan_hold().

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 3.19+
2015-11-11 23:48:34 +01:00
Johan Hedberg c81d555a26 Bluetooth: Fix crash in SMP when unpairing
When unpairing the keys stored in hci_dev are removed. If SMP is
ongoing the SMP context will also have references to these keys, so
removing them from the hci_dev lists will make the pointers invalid.
This can result in the following type of crashes:

 BUG: unable to handle kernel paging request at 6b6b6b6b
 IP: [<c11f26be>] __list_del_entry+0x44/0x71
 *pde = 00000000
 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
 Modules linked in: hci_uart btqca btusb btintel btbcm btrtl hci_vhci rfcomm bluetooth_6lowpan bluetooth
 CPU: 0 PID: 723 Comm: kworker/u5:0 Not tainted 4.3.0-rc3+ #1379
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
 Workqueue: hci0 hci_rx_work [bluetooth]
 task: f19da940 ti: f1a94000 task.ti: f1a94000
 EIP: 0060:[<c11f26be>] EFLAGS: 00010202 CPU: 0
 EIP is at __list_del_entry+0x44/0x71
 EAX: c0088d20 EBX: f30fcac0 ECX: 6b6b6b6b EDX: 6b6b6b6b
 ESI: f4b60000 EDI: c0088d20 EBP: f1a95d90 ESP: f1a95d8c
  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
 CR0: 8005003b CR2: 6b6b6b6b CR3: 319e5000 CR4: 00000690
 Stack:
  f30fcac0 f1a95db0 f82dc3e1 f1bfc000 00000000 c106524f f1bfc000 f30fd020
  f1a95dc0 f1a95dd0 f82dcbdb f1a95de0 f82dcbdb 00000067 f1bfc000 f30fd020
  f1a95de0 f1a95df0 f82d1126 00000067 f82d1126 00000006 f30fd020 f1bfc000
 Call Trace:
  [<f82dc3e1>] smp_chan_destroy+0x192/0x240 [bluetooth]
  [<c106524f>] ? trace_hardirqs_on_caller+0x14e/0x169
  [<f82dcbdb>] smp_teardown_cb+0x47/0x64 [bluetooth]
  [<f82dcbdb>] ? smp_teardown_cb+0x47/0x64 [bluetooth]
  [<f82d1126>] l2cap_chan_del+0x5d/0x14d [bluetooth]
  [<f82d1126>] ? l2cap_chan_del+0x5d/0x14d [bluetooth]
  [<f82d40ef>] l2cap_conn_del+0x109/0x17b [bluetooth]
  [<f82d40ef>] ? l2cap_conn_del+0x109/0x17b [bluetooth]
  [<f82c0205>] ? hci_event_packet+0x5b1/0x2092 [bluetooth]
  [<f82d41aa>] l2cap_disconn_cfm+0x49/0x50 [bluetooth]
  [<f82d41aa>] ? l2cap_disconn_cfm+0x49/0x50 [bluetooth]
  [<f82c0228>] hci_event_packet+0x5d4/0x2092 [bluetooth]
  [<c1332c16>] ? skb_release_data+0x6a/0x95
  [<f82ce5d4>] ? hci_send_to_monitor+0xe7/0xf4 [bluetooth]
  [<c1409708>] ? _raw_spin_unlock_irqrestore+0x44/0x57
  [<f82b3bb0>] hci_rx_work+0xf1/0x28b [bluetooth]
  [<f82b3bb0>] ? hci_rx_work+0xf1/0x28b [bluetooth]
  [<c10635a0>] ? __lock_is_held+0x2e/0x44
  [<c104772e>] process_one_work+0x232/0x432
  [<c1071ddc>] ? rcu_read_lock_sched_held+0x50/0x5a
  [<c104772e>] ? process_one_work+0x232/0x432
  [<c1047d48>] worker_thread+0x1b8/0x255
  [<c1047b90>] ? rescuer_thread+0x23c/0x23c
  [<c104bb71>] kthread+0x91/0x96
  [<c14096a7>] ? _raw_spin_unlock_irq+0x27/0x44
  [<c1409d61>] ret_from_kernel_thread+0x21/0x30
  [<c104bae0>] ? kthread_parkme+0x1e/0x1e

To solve the issue, introduce a new smp_cancel_pairing() API that can
be used to clean up the SMP state before touching the hci_dev lists.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-10-22 09:02:03 +02:00
Johan Hedberg 1ede9868f6 Bluetooth: Remove redundant (and possibly wrong) flag clearing
There's no need to clear the HCI_CONN_ENCRYPT_PEND flag in
smp_failure. In fact, this may cause the encryption tracking to get
out of sync as this has nothing to do with HCI activity.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-10-21 18:57:03 +02:00
Johan Hedberg cad20c2780 Bluetooth: Don't use remote address type to decide IRK persistency
There are LE devices on the market that start off by announcing their
public address and then once paired switch to using private address.
To be interoperable with such devices we should simply trust the fact
that we're receiving an IRK from them to indicate that they may use
private addresses in the future. Instead, simply tie the persistency
to the bonding/no-bonding information the same way as for LTKs and
CSRKs.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-10-21 00:49:21 +02:00
David S. Miller 4963ed48f2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/ipv4/arp.c

The net/ipv4/arp.c conflict was one commit adding a new
local variable while another commit was deleting one.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-26 16:08:27 -07:00
Marcel Holtmann c5080d42db Bluetooth: Fix typo in smp_ah comment for hash function
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-09-17 13:20:06 +02:00
Johan Hedberg d8949aad3e Bluetooth: Delay check for conn->smp in smp_conn_security()
There are several actions that smp_conn_security() might make that do
not require a valid SMP context (conn->smp pointer). One of these
actions is to encrypt the link with an existing LTK. If the SMP
context wasn't initialized properly we should still allow the
independent actions to be done, i.e. the check for the context should
only be done at the last possible moment.

Reported-by: Chuck Ebbert <cebbert.lkml@gmail.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.0+
2015-09-17 12:28:27 +02:00
Johan Hedberg 25ba265390 Bluetooth: Fix NULL pointer dereference in smp_conn_security
The l2cap_conn->smp pointer may be NULL for various valid reasons where SMP has
failed to initialize properly. One such scenario is when crypto support is
missing, another when the adapter has been powered on through a legacy method.
The smp_conn_security() function should have the appropriate check for this
situation to avoid NULL pointer dereferences.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.0+
2015-07-23 16:41:24 +02:00
Johan Hedberg e3f6a257a7 Bluetooth: Use actual encryption key size for SMP over BR/EDR
When pairing over SMP over BR/EDR the generated LTK has by default the
same key size as the BR/EDR Link Key. Make sure we don't set our
Pairing Request/Response max value to anything higher than that.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-06-12 11:38:45 +02:00
Johan Hedberg b1f663c91c Bluetooth: Add debugfs support for min LE encryption key size
This patch adds a debugfs control to set a different minimum LE
encryption key size. This is useful for testing that implementation of
the encryption key size handling is behaving correctly (e.g. that we
get appropriate 'Encryption Key Size' error responses when necessary).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-06-12 11:38:45 +02:00
Johan Hedberg 2fd36558f0 Bluetooth: Add debugfs support for max LE encryption key size
This patch adds a debugfs control to set a different maximum LE
encryption key size. This is useful for testing that implementation of
the encryption key size handling is behaving correctly.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-06-12 11:38:45 +02:00
Johan Hedberg 1fc62c526a Bluetooth: Fix exposing full value of shortened LTKs
When we notify user space of a new LTK or distribute an LTK to the
remote peer the value passed should be the shortened version so that
it's easy to compare values in various traces. The core spec also sets
the requirements for the shortening/masking as:

"The masking shall be done after generation and before being
distributed, used or stored."

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-06-10 10:50:06 +02:00
Johan Hedberg 8b76ce34c4 Bluetooth: Fix encryption key size handling for LTKs
The encryption key size for LTKs is supposed to be applied only at the
moment of encryption. When generating a Link Key (using LE SC) from
the LTK the full non-shortened value should be used. This patch
modifies the code to always keep the full value around and only apply
the key size when passing the value to HCI.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-06-09 09:09:06 +02:00
Johan Hedberg 011c391a09 Bluetooth: Add debug logs for legacy SMP crypto functions
To help debug legacy SMP crypto functions add debug logs of the
various values involved.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-05-19 21:07:29 +02:00
Marcel Holtmann 64dd374eac Bluetooth: Export SMP selftest result in debugfs
When SMP selftest is enabled, then besides printing the result into the
kernel message buffer, also create a debugfs file that allows retrieving
the same information.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-04-02 08:47:40 +03:00
Johan Hedberg a4368ff3ed Bluetooth: Refactor L2CAP variables into l2cap_ctrl
We're getting very close to the maximum possible size of bt_skb_cb. To
prepare to shrink the struct with the help of a union this patch moves
all L2CAP related variables into the l2cap_ctrl struct. To later add
other 'ctrl' structs the L2CAP one is renamed simple 'l2cap' instead
of 'control'.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-30 23:20:53 +02:00
Marcel Holtmann 63511f6d5b Bluetooth: Fix potential NULL dereference in SMP channel setup
When the allocation of the L2CAP channel for the BR/EDR security manager
fails, then the smp variable might be NULL. In that case do not try to
free the non-existing crypto contexts

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-18 08:30:03 +02:00
Johan Hedberg 19c5ce9c5f Bluetooth: Add workaround for broken OS X legacy SMP pairing
OS X version 10.10.2 (and possibly older versions) doesn't support LE
Secure Connections but incorrectly copies all authentication request
bits from a Security Request to its Pairing Request. The result is that
an SC capable initiator (such as BlueZ) will think OS X intends to do SC
when in fact it's incapable of it:

< ACL Data TX: Handle 3585 flags 0x00 dlen 6
      SMP: Security Request (0x0b) len 1
        Authentication requirement: Bonding, No MITM, SC, No Keypresses (0x09)
> ACL Data RX: Handle 3585 flags 0x02 dlen 11
      SMP: Pairing Request (0x01) len 6
        IO capability: KeyboardDisplay (0x04)
        OOB data: Authentication data not present (0x00)
        Authentication requirement: Bonding, No MITM, SC, No Keypresses (0x09)
        Max encryption key size: 16
        Initiator key distribution: EncKey (0x01)
        Responder key distribution: EncKey IdKey Sign (0x07)
< ACL Data TX: Handle 3585 flags 0x00 dlen 11
      SMP: Pairing Response (0x02) len 6
        IO capability: NoInputNoOutput (0x03)
        OOB data: Authentication data not present (0x00)
        Authentication requirement: Bonding, No MITM, SC, No Keypresses (0x09)
        Max encryption key size: 16
        Initiator key distribution: EncKey (0x01)
        Responder key distribution: EncKey Sign (0x05)

The pairing eventually fails when we get an unexpected Pairing Confirm
PDU instead of a Public Key PDU:

> ACL Data RX: Handle 3585 flags 0x02 dlen 21
      SMP: Pairing Confirm (0x03) len 16
        Confim value: bcc3bed31b8f313a78ec3cce32685faf

It is only at this point that we can speculate that the remote doesn't
really support SC. This patch creates a workaround for the just-works
model, however the MITM case is unsolvable because the OS X user has
already been requested to enter a PIN which we're now expected to
randomly generate and show the user (i.e. a chicken-and-egg problem).

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-17 18:58:24 +01:00
Marcel Holtmann fb334fee60 Bluetooth: Rename smp->local_rr into smp->local_rand
The variable for the out-of-band random number was badly named and
with that confusing. Just rename it to local_rand so it is clear
what value it represents.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 21:36:23 +02:00
Marcel Holtmann bc07cd696e Bluetooth: Add extra SMP_DBG statement for remote OOB data
Just for pure debugging purposes print the remote out-of-band data
that has been received and is going to be used.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 21:36:21 +02:00
Marcel Holtmann e091526dfd Bluetooth: Use smp->remote_pk + 32 instead of &smp->remote_pk[32]
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 21:36:19 +02:00
Johan Hedberg cb06d366fb Bluetooth: Add clarifying comment when setting local OOB flag
It might be a bit counterintuitive to set a 'local' flag based on remote
data. This patch adds a clarifying comment to the pairing req/rsp
handlers when setting the LOCAL_OOB flag based on the PDU received from
the remote side.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-16 20:16:08 +01:00
Johan Hedberg a8ca617c13 Bluetooth: Don't send public key if OOB data verification fails
When we receive the remote public key, if we have remote OOB data
there's no point in sending our public key to the remote if the OOB data
doesn't match. This patch moves the test for this higher up in the
smp_cmd_public_key() function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-16 17:17:38 +01:00
Johan Hedberg 94ea7257ef Bluetooth: Fix verifying confirm value when lacking remote OOB data
If we haven't received remote OOB data we cannot perform any special
checks on the confirm value. This patch updates the check after having
received the public key to only perform the verification if we have
remote OOB data present.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-16 17:16:46 +01:00
Johan Hedberg 58428563b5 Bluetooth: Set local OOB data flag if remote has our OOB data
If the SMP Pairing Request or Response PDU received from the remote
device indicates that it has received our OOB data we should set the
SMP_FLAG_LOCAL_OOB flag.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-16 17:16:46 +01:00
Johan Hedberg 1a8bab4f39 Bluetooth: Track local vs remote OOB data availability
There are several decisions in the SMP logic that depend not only on
whether we're doing SMP or not, but also whether local and/or remote OOB
data is present. This patch splits the existing SMP_FLAG_OOB into two
new flags to track local and remote OOB data respectively.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-16 17:16:45 +01:00
Johan Hedberg 882fafad71 Bluetooth: Fix local OOB data handling for SMP
We need to store the local ra/rb value in order to verify the Check
value received from the remote. This patch adds a new 'lr' for the local
ra/rb value and makes sure it gets used when verifying the DHKey Check
PDU received from the remote.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-03-16 17:16:45 +01:00
Marcel Holtmann 8e4e2ee5d8 Bluetooth: Use smp->local_pk + 32 instead of &smp->local_pk[32]
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 10:31:31 +02:00
Marcel Holtmann 33d0c03071 Bluetooth: Use OOB key pair for LE SC pairing with OOB method
The OOB public and secret key pair is different from the non-OOB pairing
procedure. SO when OOB method is in use, then use this key pair instead
of generating a new one.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 10:31:29 +02:00
Marcel Holtmann 60a27d653d Bluetooth: Add function for generating LE SC out-of-band data
This patch adds a smp_generate_oob function that allows to create
local out-of-band data that can be used for pairing and also provides
the confirmation and random value.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 10:31:27 +02:00
Marcel Holtmann 6e2dc6d113 Bluetooth: Add support for AES-CMAC hash for security manager device
The security manager device will require the use of AES-CMAC hash for
out-of-band data generation. This patch makes sure it is correctly
set up and available.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 10:31:25 +02:00
Marcel Holtmann 88a479d950 Bluetooth: Create SMP device structure for local crypto context
Every Bluetooth Low Energy controller requires a local crypto context
to handle the resolvable private addresses. At the moment this is just
a single crypto context, but for out-of-band data generation it will
require an additional. To facility this, create a struct smp_dev that
will hold all the extra information. This patch is just the refactoring
in preparation for future changes.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 10:31:05 +02:00
Marcel Holtmann 276812ec3e Bluetooth: Use kzfree instead of kfree in security manager
Within the security manager, it makes sense to use kzfree instead of
kfree for all data structures. This ensures that no key material leaks
by accident.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-16 10:30:53 +02:00
Marcel Holtmann b7cb93e528 Bluetooth: Merge hdev->dbg_flags fields into hdev->dev_flags
With the extension of hdev->dev_flags utilizing a bitmap now, the space
is no longer restricted. Merge the hdev->dbg_flags into hdev->dev_flags
to save space on 64-bit architectures. On 32-bit architectures no size
reduction happens.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-13 19:28:36 +02:00
Marcel Holtmann d7a5a11d7f Bluetooth: Introduce hci_dev_test_flag helper macro
Instead of manually coding test_bit on hdev->dev_flags all the time,
use hci_dev_test_flag helper macro.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-13 12:09:25 +02:00
Marcel Holtmann 983f9814c0 Bluetooth: Remove two else branches that are not needed
The SMP code contains two else branches that are not needed since the
successful test will actually leave the function.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2015-03-12 09:00:48 +02:00