This patch fix the issue: warning:variable 'passkey' is uninitialized
when used here
Link: https://groups.google.com/forum/#!topic/clang-built-linux/kyRKCjRsGoU
Fixes: cee5f20fec ("Bluetooth: secure bluetooth stack from bluedump attack")
Reported-by: kbuild test robot <lkp@intel.com>
Suggested-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Howard Chung <howardchung@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Attack scenario:
1. A Chromebook (let's call this device A) is paired to a legitimate
Bluetooth classic device (e.g. a speaker) (let's call this device
B).
2. A malicious device (let's call this device C) pretends to be the
Bluetooth speaker by using the same BT address.
3. If device A is not currently connected to device B, device A will
be ready to accept connection from device B in the background
(technically, doing Page Scan).
4. Therefore, device C can initiate connection to device A
(because device A is doing Page Scan) and device A will accept the
connection because device A trusts device C's address which is the
same as device B's address.
5. Device C won't be able to communicate at any high level Bluetooth
profile with device A because device A enforces that device C is
encrypted with their common Link Key, which device C doesn't have.
But device C can initiate pairing with device A with just-works
model without requiring user interaction (there is only pairing
notification). After pairing, device A now trusts device C with a
new different link key, common between device A and C.
6. From now on, device A trusts device C, so device C can at anytime
connect to device A to do any kind of high-level hijacking, e.g.
speaker hijack or mouse/keyboard hijack.
Since we don't know whether the repairing is legitimate or not,
leave the decision to user space if all the conditions below are met.
- the pairing is initialized by peer
- the authorization method is just-work
- host already had the link key to the peer
Signed-off-by: Howard Chung <howardchung@google.com>
Acked-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Salts are 16 bytes long.
Remove some extra and erroneous '0' in the human readable format used
in comments.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The debugfs entries for {min,max}_key_size are created during SMP
registration and thus it might lead to multiple attempts to create the
same entries. Avoid this by moving them to the LE controller init
section.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
MGMT command is added to receive the list of blocked keys from
user-space.
The list is used to:
1) Block keys from being distributed by the device during
the ke distribution phase of SMP.
2) Filter out any keys that were previously saved so
they are no longer used.
Signed-off-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Fixes gcc '-Wunused-but-set-variable' warning:
net/bluetooth/smp.c: In function 'smp_irk_matches':
net/bluetooth/smp.c:505:18: warning: variable 'smp' set but not used [-Wunused-but-set-variable]
net/bluetooth/smp.c: In function 'smp_generate_rpa':
net/bluetooth/smp.c:526:18: warning: variable 'smp' set but not used [-Wunused-but-set-variable]
It is not used since commit 28a220aac5 ("bluetooth: switch
to AES library")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The bluetooth code uses a bare AES cipher for the encryption operations.
Given that it carries out a set_key() operation right before every
encryption operation, this is clearly not a hot path, and so the use of
the cipher interface (which provides the best implementation available
on the system) is not really required.
In fact, when using a cipher like AES-NI or AES-CE, both the set_key()
and the encrypt() operations involve en/disabling preemption as well as
stacking and unstacking the SIMD context, and this is most certainly
not worth it for encrypting 16 bytes of data.
So let's switch to the new lightweight library interface instead.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Microsoft Surface Precision Mouse provides bogus identity address when
pairing. It connects with Static Random address but provides Public
Address in SMP Identity Address Information PDU. Address has same
value but type is different. Workaround this by dropping IRK if ID
address discrepancy is detected.
> HCI Event: LE Meta Event (0x3e) plen 19
LE Connection Complete (0x01)
Status: Success (0x00)
Handle: 75
Role: Master (0x00)
Peer address type: Random (0x01)
Peer address: E0:52:33:93:3B:21 (Static)
Connection interval: 50.00 msec (0x0028)
Connection latency: 0 (0x0000)
Supervision timeout: 420 msec (0x002a)
Master clock accuracy: 0x00
....
> ACL Data RX: Handle 75 flags 0x02 dlen 12
SMP: Identity Address Information (0x09) len 7
Address type: Public (0x00)
Address: E0:52:33:93:3B:21
Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>
Tested-by: Maarten Fonville <maarten.fonville@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199461
Cc: stable@vger.kernel.org
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.
With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP. These would all need to be fixed if any shash algorithm
actually started sleeping. For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API. However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.
Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk. It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.
Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
'shash' algorithms are always synchronous, so passing CRYPTO_ALG_ASYNC
in the mask to crypto_alloc_shash() has no effect. Many users therefore
already don't pass it, but some still do. This inconsistency can cause
confusion, especially since the way the 'mask' argument works is
somewhat counterintuitive.
Thus, just remove the unneeded CRYPTO_ALG_ASYNC flags.
This patch shouldn't change any actual behavior.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
'cipher' algorithms (single block ciphers) are always synchronous, so
passing CRYPTO_ALG_ASYNC in the mask to crypto_alloc_cipher() has no
effect. Many users therefore already don't pass it, but some still do.
This inconsistency can cause confusion, especially since the way the
'mask' argument works is somewhat counterintuitive.
Thus, just remove the unneeded CRYPTO_ALG_ASYNC flags.
This patch shouldn't change any actual behavior.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.
Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements. This makes it easier to add further
iterator types. Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.
Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself. Only the direction is required.
Signed-off-by: David Howells <dhowells@redhat.com>
Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net'
overlapped the renaming of a netlink attribute in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
A remote device may claim that it has received our OOB data, even
though we never geneated it. Add a new flag to track whether we
actually have OOB data, and ignore the remote peer's flag if haven't
generated OOB data.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Re-use kstrtobool_from_user() instead of open coded variant.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
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>
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>
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>
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>
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
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>
* 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>
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>
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>
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
...
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+
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>
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+
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>
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>
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>
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+
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+
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
