linux-stable.git/crypto/gcm.c, branch linux-3.16.y

crypto: gcm - wait for crypto op not signal safe

2017-09-15T17:29:48+00:00

commit f3ad587070d6bd961ab942b3fd7a85d00dfc934b upstream.

crypto_gcm_setkey() was using wait_for_completion_interruptible() to
wait for completion of async crypto op but if a signal occurs it
may return before DMA ops of HW crypto provider finish, thus
corrupting the data buffer that is kfree'ed in this case.

Resolve this by using wait_for_completion() instead.

Reported-by: Eric Biggers 
Signed-off-by: Gilad Ben-Yossef 
Signed-off-by: Herbert Xu 
Signed-off-by: Ben Hutchings

crypto: gcm - Fix IV buffer size in crypto_gcm_setkey

2017-02-23T03:54:07+00:00

commit 50d2e6dc1f83db0563c7d6603967bf9585ce934b upstream.

The cipher block size for GCM is 16 bytes, and thus the CTR transform
used in crypto_gcm_setkey() will also expect a 16-byte IV. However,
the code currently reserves only 8 bytes for the IV, causing
an out-of-bounds access in the CTR transform. This patch fixes
the issue by setting the size of the IV buffer to 16 bytes.

Fixes: 84c911523020 ("[CRYPTO] gcm: Add support for async ciphers")
Signed-off-by: Ondrej Mosnacek 
Signed-off-by: Herbert Xu 
Signed-off-by: Ben Hutchings

crypto: gcm - Filter out async ghash if necessary

2016-11-20T01:16:41+00:00

commit b30bdfa86431afbafe15284a3ad5ac19b49b88e3 upstream.

As it is if you ask for a sync gcm you may actually end up with
an async one because it does not filter out async implementations
of ghash.

This patch fixes this by adding the necessary filter when looking
for ghash.

Signed-off-by: Herbert Xu 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

crypto: gcm - Fix rfc4543 decryption crash

2016-04-30T22:06:15+00:00

This bug has already bee fixed upstream since 4.2.  However, it
was fixed during the AEAD conversion so no fix was backported to
the older kernels.

[bwh: The upstream commit was adcbc688fe2f ("crypto: gcm - Convert to
new AEAD interface")]

When we do an RFC 4543 decryption, we will end up writing the
ICV beyond the end of the dst buffer.  This should lead to a
crash but for some reason it was never noticed.

This patch fixes it by only writing back the ICV for encryption.

Fixes: d733ac90f9fe ("crypto: gcm - fix rfc4543 to handle async...")
Reported-by: Patrick Meyer 
Signed-off-by: Herbert Xu

crypto: include crypto- module prefix in template

2015-02-04T10:57:49+00:00

commit 4943ba16bbc2db05115707b3ff7b4874e9e3c560 upstream.

This adds the module loading prefix "crypto-" to the template lookup
as well.

For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":

	net-pf-38
	algif-hash
	crypto-vfat(blowfish)
	crypto-vfat(blowfish)-all
	crypto-vfat

Reported-by: Mathias Krause 
Signed-off-by: Kees Cook 
Acked-by: Mathias Krause 
Signed-off-by: Herbert Xu 
[ luis: backported to 3.16: dropped changes to:
  - crypto/mcryptd.c ]
Signed-off-by: Luis Henriques

crypto: prefix module autoloading with "crypto-"

2015-02-04T10:57:48+00:00

commit 5d26a105b5a73e5635eae0629b42fa0a90e07b7b upstream.

This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:

https://lkml.org/lkml/2013/3/4/70

Signed-off-by: Kees Cook 
Signed-off-by: Herbert Xu 
[ luis: backported to 3.16: dropped changes to:
  - arch/arm/crypto/sha1_neon_glue.c
  - arch/arm/crypto/sha512_neon_glue.c
  - arch/x86/crypto/des3_ede_glue.c
  - drivers/crypto/qat/qat_common/adf_ctl_drv.c ]
Signed-off-by: Luis Henriques

crypto: crypto_memneq - add equality testing of memory regions w/o timing leaks

2013-10-07T06:17:06+00:00

When comparing MAC hashes, AEAD authentication tags, or other hash
values in the context of authentication or integrity checking, it
is important not to leak timing information to a potential attacker,
i.e. when communication happens over a network.

Bytewise memory comparisons (such as memcmp) are usually optimized so
that they return a nonzero value as soon as a mismatch is found. E.g,
on x86_64/i5 for 512 bytes this can be ~50 cyc for a full mismatch
and up to ~850 cyc for a full match (cold). This early-return behavior
can leak timing information as a side channel, allowing an attacker to
iteratively guess the correct result.

This patch adds a new method crypto_memneq ("memory not equal to each
other") to the crypto API that compares memory areas of the same length
in roughly "constant time" (cache misses could change the timing, but
since they don't reveal information about the content of the strings
being compared, they are effectively benign). Iow, best and worst case
behaviour take the same amount of time to complete (in contrast to
memcmp).

Note that crypto_memneq (unlike memcmp) can only be used to test for
equality or inequality, NOT for lexicographical order. This, however,
is not an issue for its use-cases within the crypto API.

We tried to locate all of the places in the crypto API where memcmp was
being used for authentication or integrity checking, and convert them
over to crypto_memneq.

crypto_memneq is declared noinline, placed in its own source file,
and compiled with optimizations that might increase code size disabled
("Os") because a smart compiler (or LTO) might notice that the return
value is always compared against zero/nonzero, and might then
reintroduce the same early-return optimization that we are trying to
avoid.

Using #pragma or __attribute__ optimization annotations of the code
for disabling optimization was avoided as it seems to be considered
broken or unmaintained for long time in GCC [1]. Therefore, we work
around that by specifying the compile flag for memneq.o directly in
the Makefile. We found that this seems to be most appropriate.

As we use ("Os"), this patch also provides a loop-free "fast-path" for
frequently used 16 byte digests. Similarly to kernel library string
functions, leave an option for future even further optimized architecture
specific assembler implementations.

This was a joint work of James Yonan and Daniel Borkmann. Also thanks
for feedback from Florian Weimer on this and earlier proposals [2].

  [1] http://gcc.gnu.org/ml/gcc/2012-07/msg00211.html
  [2] https://lkml.org/lkml/2013/2/10/131

Signed-off-by: James Yonan 
Signed-off-by: Daniel Borkmann 
Cc: Florian Weimer 
Signed-off-by: Herbert Xu

Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

2013-05-02T21:53:12+00:00

Pull crypto update from Herbert Xu:

 - XTS mode optimisation for twofish/cast6/camellia/aes on x86

 - AVX2/x86_64 implementation for blowfish/twofish/serpent/camellia

 - SSSE3/AVX/AVX2 optimisations for sha256/sha512

 - Added driver for SAHARA2 crypto accelerator

 - Fix for GMAC when used in non-IPsec secnarios

 - Added generic CMAC implementation (including IPsec glue)

 - IP update for crypto/atmel

 - Support for more than one device in hwrng/timeriomem

 - Added Broadcom BCM2835 RNG driver

 - Misc fixes

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (59 commits)
  crypto: caam - fix job ring cleanup code
  crypto: camellia - add AVX2/AES-NI/x86_64 assembler implementation of camellia cipher
  crypto: serpent - add AVX2/x86_64 assembler implementation of serpent cipher
  crypto: twofish - add AVX2/x86_64 assembler implementation of twofish cipher
  crypto: blowfish - add AVX2/x86_64 implementation of blowfish cipher
  crypto: tcrypt - add async cipher speed tests for blowfish
  crypto: testmgr - extend camellia test-vectors for camellia-aesni/avx2
  crypto: aesni_intel - fix Kconfig problem with CRYPTO_GLUE_HELPER_X86
  crypto: aesni_intel - add more optimized XTS mode for x86-64
  crypto: x86/camellia-aesni-avx - add more optimized XTS code
  crypto: cast6-avx: use new optimized XTS code
  crypto: x86/twofish-avx - use optimized XTS code
  crypto: x86 - add more optimized XTS-mode for serpent-avx
  xfrm: add rfc4494 AES-CMAC-96 support
  crypto: add CMAC support to CryptoAPI
  crypto: testmgr - add empty test vectors for null ciphers
  crypto: testmgr - add AES GMAC test vectors
  crypto: gcm - fix rfc4543 to handle async crypto correctly
  crypto: gcm - make GMAC work when dst and src are different
  hwrng: timeriomem - added devicetree hooks
  ...

crypto: gcm - fix rfc4543 to handle async crypto correctly

2013-04-25T13:01:47+00:00

If the gcm cipher used by rfc4543 does not complete request immediately,
the authentication tag is not copied to destination buffer. Patch adds
correct async logic for this case.

Signed-off-by: Jussi Kivilinna 
Signed-off-by: Herbert Xu

crypto: gcm - make GMAC work when dst and src are different

2013-04-25T13:01:46+00:00

The GMAC code assumes that dst==src, which causes problems when trying to add
rfc4543(gcm(aes)) test vectors.

So fix this code to work when source and destination buffer are different.

Signed-off-by: Jussi Kivilinna 
Signed-off-by: Herbert Xu