Commit Graph

2379 Commits

Author SHA1 Message Date
Kees Cook b350bee5ea crypto: skcipher - Introduce crypto_sync_skcipher
In preparation for removal of VLAs due to skcipher requests on the stack
via SKCIPHER_REQUEST_ON_STACK() usage, this introduces the infrastructure
for the "sync skcipher" tfm, which is for handling the on-stack cases of
skcipher, which are always non-ASYNC and have a known limited request
size.

The crypto API additions:

	struct crypto_sync_skcipher (wrapper for struct crypto_skcipher)
	crypto_alloc_sync_skcipher()
	crypto_free_sync_skcipher()
	crypto_sync_skcipher_setkey()
	crypto_sync_skcipher_get_flags()
	crypto_sync_skcipher_set_flags()
	crypto_sync_skcipher_clear_flags()
	crypto_sync_skcipher_blocksize()
	crypto_sync_skcipher_ivsize()
	crypto_sync_skcipher_reqtfm()
	skcipher_request_set_sync_tfm()
	SYNC_SKCIPHER_REQUEST_ON_STACK() (with tfm type check)

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-28 12:46:06 +08:00
Dan Aloni 3944f139d5 crypto: fix a memory leak in rsa-kcs1pad's encryption mode
The encryption mode of pkcs1pad never uses out_sg and out_buf, so
there's no need to allocate the buffer, which presently is not even
being freed.

CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: linux-crypto@vger.kernel.org
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-28 12:46:06 +08:00
Ondrej Mosnacek ac3c8f36c3 crypto: lrw - Do not use auxiliary buffer
This patch simplifies the LRW template to recompute the LRW tweaks from
scratch in the second pass and thus also removes the need to allocate a
dynamic buffer using kmalloc().

As discussed at [1], the use of kmalloc causes deadlocks with dm-crypt.

PERFORMANCE MEASUREMENTS (x86_64)
Performed using: https://gitlab.com/omos/linux-crypto-bench
Crypto driver used: lrw(ecb-aes-aesni)

The results show that the new code has about the same performance as the
old code. For 512-byte message it seems to be even slightly faster, but
that might be just noise.

Before:
       ALGORITHM KEY (b)        DATA (B)   TIME ENC (ns)   TIME DEC (ns)
        lrw(aes)     256              64             200             203
        lrw(aes)     320              64             202             204
        lrw(aes)     384              64             204             205
        lrw(aes)     256             512             415             415
        lrw(aes)     320             512             432             440
        lrw(aes)     384             512             449             451
        lrw(aes)     256            4096            1838            1995
        lrw(aes)     320            4096            2123            1980
        lrw(aes)     384            4096            2100            2119
        lrw(aes)     256           16384            7183            6954
        lrw(aes)     320           16384            7844            7631
        lrw(aes)     384           16384            8256            8126
        lrw(aes)     256           32768           14772           14484
        lrw(aes)     320           32768           15281           15431
        lrw(aes)     384           32768           16469           16293

After:
       ALGORITHM KEY (b)        DATA (B)   TIME ENC (ns)   TIME DEC (ns)
        lrw(aes)     256              64             197             196
        lrw(aes)     320              64             200             197
        lrw(aes)     384              64             203             199
        lrw(aes)     256             512             385             380
        lrw(aes)     320             512             401             395
        lrw(aes)     384             512             415             415
        lrw(aes)     256            4096            1869            1846
        lrw(aes)     320            4096            2080            1981
        lrw(aes)     384            4096            2160            2109
        lrw(aes)     256           16384            7077            7127
        lrw(aes)     320           16384            7807            7766
        lrw(aes)     384           16384            8108            8357
        lrw(aes)     256           32768           14111           14454
        lrw(aes)     320           32768           15268           15082
        lrw(aes)     384           32768           16581           16250

[1] https://lkml.org/lkml/2018/8/23/1315

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-21 13:24:52 +08:00
Ondrej Mosnacek c778f96bf3 crypto: lrw - Optimize tweak computation
This patch rewrites the tweak computation to a slightly simpler method
that performs less bswaps. Based on performance measurements the new
code seems to provide slightly better performance than the old one.

PERFORMANCE MEASUREMENTS (x86_64)
Performed using: https://gitlab.com/omos/linux-crypto-bench
Crypto driver used: lrw(ecb-aes-aesni)

Before:
       ALGORITHM KEY (b)        DATA (B)   TIME ENC (ns)   TIME DEC (ns)
        lrw(aes)     256              64             204             286
        lrw(aes)     320              64             227             203
        lrw(aes)     384              64             208             204
        lrw(aes)     256             512             441             439
        lrw(aes)     320             512             456             455
        lrw(aes)     384             512             469             483
        lrw(aes)     256            4096            2136            2190
        lrw(aes)     320            4096            2161            2213
        lrw(aes)     384            4096            2295            2369
        lrw(aes)     256           16384            7692            7868
        lrw(aes)     320           16384            8230            8691
        lrw(aes)     384           16384            8971            8813
        lrw(aes)     256           32768           15336           15560
        lrw(aes)     320           32768           16410           16346
        lrw(aes)     384           32768           18023           17465

After:
       ALGORITHM KEY (b)        DATA (B)   TIME ENC (ns)   TIME DEC (ns)
        lrw(aes)     256              64             200             203
        lrw(aes)     320              64             202             204
        lrw(aes)     384              64             204             205
        lrw(aes)     256             512             415             415
        lrw(aes)     320             512             432             440
        lrw(aes)     384             512             449             451
        lrw(aes)     256            4096            1838            1995
        lrw(aes)     320            4096            2123            1980
        lrw(aes)     384            4096            2100            2119
        lrw(aes)     256           16384            7183            6954
        lrw(aes)     320           16384            7844            7631
        lrw(aes)     384           16384            8256            8126
        lrw(aes)     256           32768           14772           14484
        lrw(aes)     320           32768           15281           15431
        lrw(aes)     384           32768           16469           16293

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-21 13:24:52 +08:00
Ondrej Mosnacek dc6d6d5a58 crypto: testmgr - Add test for LRW counter wrap-around
This patch adds a test vector for lrw(aes) that triggers wrap-around of
the counter, which is a tricky corner case.

Suggested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-21 13:24:52 +08:00
Ondrej Mosnacek fbe1a850b3 crypto: lrw - Fix out-of bounds access on counter overflow
When the LRW block counter overflows, the current implementation returns
128 as the index to the precomputed multiplication table, which has 128
entries. This patch fixes it to return the correct value (127).

Fixes: 64470f1b85 ("[CRYPTO] lrw: Liskov Rivest Wagner, a tweakable narrow block cipher mode")
Cc: <stable@vger.kernel.org> # 2.6.20+
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-21 13:24:51 +08:00
Horia Geantă 331351f89c crypto: tcrypt - fix ghash-generic speed test
ghash is a keyed hash algorithm, thus setkey needs to be called.
Otherwise the following error occurs:
$ modprobe tcrypt mode=318 sec=1
testing speed of async ghash-generic (ghash-generic)
tcrypt: test  0 (   16 byte blocks,   16 bytes per update,   1 updates):
tcrypt: hashing failed ret=-126

Cc: <stable@vger.kernel.org> # 4.6+
Fixes: 0660511c0b ("crypto: tcrypt - Use ahash")
Tested-by: Franck Lenormand <franck.lenormand@nxp.com>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-21 13:24:51 +08:00
Eric Biggers a5e9f55709 crypto: chacha20 - Fix chacha20_block() keystream alignment (again)
In commit 9f480faec5 ("crypto: chacha20 - Fix keystream alignment for
chacha20_block()"), I had missed that chacha20_block() can be called
directly on the buffer passed to get_random_bytes(), which can have any
alignment.  So, while my commit didn't break anything, it didn't fully
solve the alignment problems.

Revert my solution and just update chacha20_block() to use
put_unaligned_le32(), so the output buffer need not be aligned.
This is simpler, and on many CPUs it's the same speed.

But, I kept the 'tmp' buffers in extract_crng_user() and
_get_random_bytes() 4-byte aligned, since that alignment is actually
needed for _crng_backtrack_protect() too.

Reported-by: Stephan Müller <smueller@chronox.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-21 13:24:50 +08:00
Ondrej Mosnacek 78105c7e76 crypto: xts - Drop use of auxiliary buffer
Since commit acb9b159c7 ("crypto: gf128mul - define gf128mul_x_* in
gf128mul.h"), the gf128mul_x_*() functions are very fast and therefore
caching the computed XTS tweaks has only negligible advantage over
computing them twice.

In fact, since the current caching implementation limits the size of
the calls to the child ecb(...) algorithm to PAGE_SIZE (usually 4096 B),
it is often actually slower than the simple recomputing implementation.

This patch simplifies the XTS template to recompute the XTS tweaks from
scratch in the second pass and thus also removes the need to allocate a
dynamic buffer using kmalloc().

As discussed at [1], the use of kmalloc causes deadlocks with dm-crypt.

PERFORMANCE RESULTS
I measured time to encrypt/decrypt a memory buffer of varying sizes with
xts(ecb-aes-aesni) using a tool I wrote ([2]) and the results suggest
that after this patch the performance is either better or comparable for
both small and large buffers. Note that there is a lot of noise in the
measurements, but the overall difference is easy to see.

Old code:
       ALGORITHM KEY (b)        DATA (B)   TIME ENC (ns)   TIME DEC (ns)
        xts(aes)     256              64             331             328
        xts(aes)     384              64             332             333
        xts(aes)     512              64             338             348
        xts(aes)     256             512             889             920
        xts(aes)     384             512            1019             993
        xts(aes)     512             512            1032             990
        xts(aes)     256            4096            2152            2292
        xts(aes)     384            4096            2453            2597
        xts(aes)     512            4096            3041            2641
        xts(aes)     256           16384            9443            8027
        xts(aes)     384           16384            8536            8925
        xts(aes)     512           16384            9232            9417
        xts(aes)     256           32768           16383           14897
        xts(aes)     384           32768           17527           16102
        xts(aes)     512           32768           18483           17322

New code:
       ALGORITHM KEY (b)        DATA (B)   TIME ENC (ns)   TIME DEC (ns)
        xts(aes)     256              64             328             324
        xts(aes)     384              64             324             319
        xts(aes)     512              64             320             322
        xts(aes)     256             512             476             473
        xts(aes)     384             512             509             492
        xts(aes)     512             512             531             514
        xts(aes)     256            4096            2132            1829
        xts(aes)     384            4096            2357            2055
        xts(aes)     512            4096            2178            2027
        xts(aes)     256           16384            6920            6983
        xts(aes)     384           16384            8597            7505
        xts(aes)     512           16384            7841            8164
        xts(aes)     256           32768           13468           12307
        xts(aes)     384           32768           14808           13402
        xts(aes)     512           32768           15753           14636

[1] https://lkml.org/lkml/2018/8/23/1315
[2] https://gitlab.com/omos/linux-crypto-bench

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-21 13:24:50 +08:00
Martin K. Petersen dd8b083f9a crypto: api - Introduce notifier for new crypto algorithms
Introduce a facility that can be used to receive a notification
callback when a new algorithm becomes available. This can be used by
existing crypto registrations to trigger a switch from a software-only
algorithm to a hardware-accelerated version.

A new CRYPTO_MSG_ALG_LOADED state is introduced to the existing crypto
notification chain, and the register/unregister functions are exported
so they can be called by subsystems outside of crypto.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Suggested-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:37:04 +08:00
Ard Biesheuvel ab8085c130 crypto: x86 - remove SHA multibuffer routines and mcryptd
As it turns out, the AVX2 multibuffer SHA routines are currently
broken [0], in a way that would have likely been noticed if this
code were in wide use. Since the code is too complicated to be
maintained by anyone except the original authors, and since the
performance benefits for real-world use cases are debatable to
begin with, it is better to drop it entirely for the moment.

[0] https://marc.info/?l=linux-crypto-vger&m=153476243825350&w=2

Suggested-by: Eric Biggers <ebiggers@google.com>
Cc: Megha Dey <megha.dey@linux.intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:37:04 +08:00
Kees Cook f3569fd613 crypto: shash - Remove VLA usage in unaligned hashing
In the quest to remove all stack VLA usage from the kernel[1], this uses
the newly defined max alignment to perform unaligned hashing to avoid
VLAs, and drops the helper function while adding sanity checks on the
resulting buffer sizes. Additionally, the __aligned_largest macro is
removed since this helper was the only user.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:37:03 +08:00
Kees Cook a9f7f88a12 crypto: api - Introduce generic max blocksize and alignmask
In the quest to remove all stack VLA usage from the kernel[1], this
exposes a new general upper bound on crypto blocksize and alignmask
(higher than for the existing cipher limits) for VLA removal,
and introduces new checks.

At present, the highest cra_alignmask in the kernel is 63. The highest
cra_blocksize is 144 (SHA3_224_BLOCK_SIZE, 18 8-byte words). For the
new blocksize limit, I went with 160 (20 8-byte words).

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:35:04 +08:00
Kees Cook b68a7ec1e9 crypto: hash - Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
removes the VLAs in SHASH_DESC_ON_STACK (via crypto_shash_descsize())
by using the maximum allowable size (which is now more clearly captured
in a macro), along with a few other cases. Similar limits are turned into
macros as well.

A review of existing sizes shows that SHA512_DIGEST_SIZE (64) is the
largest digest size and that sizeof(struct sha3_state) (360) is the
largest descriptor size. The corresponding maximums are reduced.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:35:03 +08:00
Ard Biesheuvel ebf533adc8 crypto: ccm - Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this drops
AHASH_REQUEST_ON_STACK by preallocating the ahash request area combined
with the skcipher area (which are not used at the same time).

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:35:03 +08:00
Kees Cook 3bdd23f886 crypto: xcbc - Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this uses
the maximum blocksize and adds a sanity check. For xcbc, the blocksize
must always be 16, so use that, since it's already being enforced during
instantiation.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:35:03 +08:00
Jason A. Donenfeld 578bdaabd0 crypto: speck - remove Speck
These are unused, undesired, and have never actually been used by
anybody. The original authors of this code have changed their mind about
its inclusion. While originally proposed for disk encryption on low-end
devices, the idea was discarded [1] in favor of something else before
that could really get going. Therefore, this patch removes Speck.

[1] https://marc.info/?l=linux-crypto-vger&m=153359499015659

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Cc: stable@vger.kernel.org
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:35:03 +08:00
Linus Torvalds 13bf2cf9e2 DMAengine updates for v4.19-rc1
This round brings couple of framework changes, a new driver and usual driver
 updates:
  - New managed helper for dmaengine framework registration
  - Split dmaengine pause capability to pause and resume and allow drivers to
    report that individually
  - Update dma_request_chan_by_mask() to handle deferred probing
  - Move imx-sdma to use virt-dma
  - New driver for Actions Semi Owl family S900 controller
  - Minor updates to intel, renesas, mv_xor, pl330 etc
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Merge tag 'dmaengine-4.19-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull DMAengine updates from Vinod Koul:
 "This round brings couple of framework changes, a new driver and usual
  driver updates:

   - new managed helper for dmaengine framework registration

   - split dmaengine pause capability to pause and resume and allow
     drivers to report that individually

   - update dma_request_chan_by_mask() to handle deferred probing

   - move imx-sdma to use virt-dma

   - new driver for Actions Semi Owl family S900 controller

   - minor updates to intel, renesas, mv_xor, pl330 etc"

* tag 'dmaengine-4.19-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (46 commits)
  dmaengine: Add Actions Semi Owl family S900 DMA driver
  dt-bindings: dmaengine: Add binding for Actions Semi Owl SoCs
  dmaengine: sh: rcar-dmac: Should not stop the DMAC by rcar_dmac_sync_tcr()
  dmaengine: mic_x100_dma: use the new helper to simplify the code
  dmaengine: add a new helper dmaenginem_async_device_register
  dmaengine: imx-sdma: add memcpy interface
  dmaengine: imx-sdma: add SDMA_BD_MAX_CNT to replace '0xffff'
  dmaengine: dma_request_chan_by_mask() to handle deferred probing
  dmaengine: pl330: fix irq race with terminate_all
  dmaengine: Revert "dmaengine: mv_xor_v2: enable COMPILE_TEST"
  dmaengine: mv_xor_v2: use {lower,upper}_32_bits to configure HW descriptor address
  dmaengine: mv_xor_v2: enable COMPILE_TEST
  dmaengine: mv_xor_v2: move unmap to before callback
  dmaengine: mv_xor_v2: convert callback to helper function
  dmaengine: mv_xor_v2: kill the tasklets upon exit
  dmaengine: mv_xor_v2: explicitly freeup irq
  dmaengine: sh: rcar-dmac: Add dma_pause operation
  dmaengine: sh: rcar-dmac: add a new function to clear CHCR.DE with barrier
  dmaengine: idma64: Support dmaengine_terminate_sync()
  dmaengine: hsu: Support dmaengine_terminate_sync()
  ...
2018-08-18 15:55:59 -07:00
Yannik Sembritzki 817aef2600 Replace magic for trusting the secondary keyring with #define
Replace the use of a magic number that indicates that verify_*_signature()
should use the secondary keyring with a symbol.

Signed-off-by: Yannik Sembritzki <yannik@sembritzki.me>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: keyrings@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-16 09:57:20 -07:00
Linus Torvalds f91e654474 Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull integrity updates from James Morris:
 "This adds support for EVM signatures based on larger digests, contains
  a new audit record AUDIT_INTEGRITY_POLICY_RULE to differentiate the
  IMA policy rules from the IMA-audit messages, addresses two deadlocks
  due to either loading or searching for crypto algorithms, and cleans
  up the audit messages"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  EVM: fix return value check in evm_write_xattrs()
  integrity: prevent deadlock during digsig verification.
  evm: Allow non-SHA1 digital signatures
  evm: Don't deadlock if a crypto algorithm is unavailable
  integrity: silence warning when CONFIG_SECURITYFS is not enabled
  ima: Differentiate auditing policy rules from "audit" actions
  ima: Do not audit if CONFIG_INTEGRITY_AUDIT is not set
  ima: Use audit_log_format() rather than audit_log_string()
  ima: Call audit_log_string() rather than logging it untrusted
2018-08-15 22:54:12 -07:00
Linus Torvalds dafa5f6577 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Fix dcache flushing crash in skcipher.
   - Add hash finup self-tests.
   - Reschedule during speed tests.

  Algorithms:
   - Remove insecure vmac and replace it with vmac64.
   - Add public key verification for DH/ECDH.

  Drivers:
   - Decrease priority of sha-mb on x86.
   - Improve NEON latency/throughput on ARM64.
   - Add md5/sha384/sha512/des/3des to inside-secure.
   - Support eip197d in inside-secure.
   - Only register algorithms supported by the host in virtio.
   - Add cts and remove incompatible cts1 from ccree.
   - Add hisilicon SEC security accelerator driver.
   - Replace msm hwrng driver with qcom pseudo rng driver.

  Misc:
   - Centralize CRC polynomials"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (121 commits)
  crypto: arm64/ghash-ce - implement 4-way aggregation
  crypto: arm64/ghash-ce - replace NEON yield check with block limit
  crypto: hisilicon - sec_send_request() can be static
  lib/mpi: remove redundant variable esign
  crypto: arm64/aes-ce-gcm - don't reload key schedule if avoidable
  crypto: arm64/aes-ce-gcm - implement 2-way aggregation
  crypto: arm64/aes-ce-gcm - operate on two input blocks at a time
  crypto: dh - make crypto_dh_encode_key() make robust
  crypto: dh - fix calculating encoded key size
  crypto: ccp - Check for NULL PSP pointer at module unload
  crypto: arm/chacha20 - always use vrev for 16-bit rotates
  crypto: ccree - allow bigger than sector XTS op
  crypto: ccree - zero all of request ctx before use
  crypto: ccree - remove cipher ivgen left overs
  crypto: ccree - drop useless type flag during reg
  crypto: ablkcipher - fix crash flushing dcache in error path
  crypto: blkcipher - fix crash flushing dcache in error path
  crypto: skcipher - fix crash flushing dcache in error path
  crypto: skcipher - remove unnecessary setting of walk->nbytes
  crypto: scatterwalk - remove scatterwalk_samebuf()
  ...
2018-08-15 16:01:47 -07:00
Eric Biggers d6e43798b3 crypto: dh - make crypto_dh_encode_key() make robust
Make it return -EINVAL if crypto_dh_key_len() is incorrect rather than
overflowing the buffer.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:06 +08:00
Eric Biggers 35f7d5225f crypto: dh - fix calculating encoded key size
It was forgotten to increase DH_KPP_SECRET_MIN_SIZE to include 'q_size',
causing an out-of-bounds write of 4 bytes in crypto_dh_encode_key(), and
an out-of-bounds read of 4 bytes in crypto_dh_decode_key().  Fix it, and
fix the lengths of the test vectors to match this.

Reported-by: syzbot+6d38d558c25b53b8f4ed@syzkaller.appspotmail.com
Fixes: e3fe0ae129 ("crypto: dh - add public key verification test")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:06 +08:00
Eric Biggers 318abdfbe7 crypto: ablkcipher - fix crash flushing dcache in error path
Like the skcipher_walk and blkcipher_walk cases:

scatterwalk_done() is only meant to be called after a nonzero number of
bytes have been processed, since scatterwalk_pagedone() will flush the
dcache of the *previous* page.  But in the error case of
ablkcipher_walk_done(), e.g. if the input wasn't an integer number of
blocks, scatterwalk_done() was actually called after advancing 0 bytes.
This caused a crash ("BUG: unable to handle kernel paging request")
during '!PageSlab(page)' on architectures like arm and arm64 that define
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was
page-aligned as in that case walk->offset == 0.

Fix it by reorganizing ablkcipher_walk_done() to skip the
scatterwalk_advance() and scatterwalk_done() if an error has occurred.

Reported-by: Liu Chao <liuchao741@huawei.com>
Fixes: bf06099db1 ("crypto: skcipher - Add ablkcipher_walk interfaces")
Cc: <stable@vger.kernel.org> # v2.6.35+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:04 +08:00
Eric Biggers 0868def3e4 crypto: blkcipher - fix crash flushing dcache in error path
Like the skcipher_walk case:

scatterwalk_done() is only meant to be called after a nonzero number of
bytes have been processed, since scatterwalk_pagedone() will flush the
dcache of the *previous* page.  But in the error case of
blkcipher_walk_done(), e.g. if the input wasn't an integer number of
blocks, scatterwalk_done() was actually called after advancing 0 bytes.
This caused a crash ("BUG: unable to handle kernel paging request")
during '!PageSlab(page)' on architectures like arm and arm64 that define
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was
page-aligned as in that case walk->offset == 0.

Fix it by reorganizing blkcipher_walk_done() to skip the
scatterwalk_advance() and scatterwalk_done() if an error has occurred.

This bug was found by syzkaller fuzzing.

Reproducer, assuming ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE:

	#include <linux/if_alg.h>
	#include <sys/socket.h>
	#include <unistd.h>

	int main()
	{
		struct sockaddr_alg addr = {
			.salg_type = "skcipher",
			.salg_name = "ecb(aes-generic)",
		};
		char buffer[4096] __attribute__((aligned(4096))) = { 0 };
		int fd;

		fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
		bind(fd, (void *)&addr, sizeof(addr));
		setsockopt(fd, SOL_ALG, ALG_SET_KEY, buffer, 16);
		fd = accept(fd, NULL, NULL);
		write(fd, buffer, 15);
		read(fd, buffer, 15);
	}

Reported-by: Liu Chao <liuchao741@huawei.com>
Fixes: 5cde0af2a9 ("[CRYPTO] cipher: Added block cipher type")
Cc: <stable@vger.kernel.org> # v2.6.19+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:04 +08:00
Eric Biggers 8088d3dd4d crypto: skcipher - fix crash flushing dcache in error path
scatterwalk_done() is only meant to be called after a nonzero number of
bytes have been processed, since scatterwalk_pagedone() will flush the
dcache of the *previous* page.  But in the error case of
skcipher_walk_done(), e.g. if the input wasn't an integer number of
blocks, scatterwalk_done() was actually called after advancing 0 bytes.
This caused a crash ("BUG: unable to handle kernel paging request")
during '!PageSlab(page)' on architectures like arm and arm64 that define
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was
page-aligned as in that case walk->offset == 0.

Fix it by reorganizing skcipher_walk_done() to skip the
scatterwalk_advance() and scatterwalk_done() if an error has occurred.

This bug was found by syzkaller fuzzing.

Reproducer, assuming ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE:

	#include <linux/if_alg.h>
	#include <sys/socket.h>
	#include <unistd.h>

	int main()
	{
		struct sockaddr_alg addr = {
			.salg_type = "skcipher",
			.salg_name = "cbc(aes-generic)",
		};
		char buffer[4096] __attribute__((aligned(4096))) = { 0 };
		int fd;

		fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
		bind(fd, (void *)&addr, sizeof(addr));
		setsockopt(fd, SOL_ALG, ALG_SET_KEY, buffer, 16);
		fd = accept(fd, NULL, NULL);
		write(fd, buffer, 15);
		read(fd, buffer, 15);
	}

Reported-by: Liu Chao <liuchao741@huawei.com>
Fixes: b286d8b1a6 ("crypto: skcipher - Add skcipher walk interface")
Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:04 +08:00
Eric Biggers 2a57c0be22 crypto: skcipher - remove unnecessary setting of walk->nbytes
Setting 'walk->nbytes = walk->total' in skcipher_walk_first() doesn't
make sense because actually walk->nbytes needs to be set to the length
of the first step in the walk, which may be less than walk->total.  This
is done by skcipher_walk_next() which is called immediately afterwards.
Also walk->nbytes was already set to 0 in skcipher_walk_skcipher(),
which is a better default value in case it's forgotten to be set later.

Therefore, remove the unnecessary assignment to walk->nbytes.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:04 +08:00
Eric Biggers 8c30fbe63e crypto: scatterwalk - remove 'chain' argument from scatterwalk_crypto_chain()
All callers pass chain=0 to scatterwalk_crypto_chain().

Remove this unneeded parameter.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:03 +08:00
Eric Biggers 0567fc9e90 crypto: skcipher - fix aligning block size in skcipher_copy_iv()
The ALIGN() macro needs to be passed the alignment, not the alignmask
(which is the alignment minus 1).

Fixes: b286d8b1a6 ("crypto: skcipher - Add skcipher walk interface")
Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:03 +08:00
Horia Geantă 2af632996b crypto: tcrypt - reschedule during speed tests
Avoid RCU stalls in the case of non-preemptible kernel and lengthy
speed tests by rescheduling when advancing from one block size
to another.

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:06:02 +08:00
Stephan Müller 43490e8046 crypto: drbg - in-place cipher operation for CTR
The cipher implementations of the kernel crypto API favor in-place
cipher operations. Thus, switch the CTR cipher operation in the DRBG to
perform in-place operations. This is implemented by using the output
buffer as input buffer and zeroizing it before the cipher operation to
implement a CTR encryption of a NULL buffer.

The speed improvement is quite visibile with the following comparison
using the LRNG implementation.

Without the patch set:

      16 bytes|           12.267661 MB/s|    61338304 bytes |  5000000213 ns
      32 bytes|           23.603770 MB/s|   118018848 bytes |  5000000073 ns
      64 bytes|           46.732262 MB/s|   233661312 bytes |  5000000241 ns
     128 bytes|           90.038042 MB/s|   450190208 bytes |  5000000244 ns
     256 bytes|          160.399616 MB/s|   801998080 bytes |  5000000393 ns
     512 bytes|          259.878400 MB/s|  1299392000 bytes |  5000001675 ns
    1024 bytes|          386.050662 MB/s|  1930253312 bytes |  5000001661 ns
    2048 bytes|          493.641728 MB/s|  2468208640 bytes |  5000001598 ns
    4096 bytes|          581.835981 MB/s|  2909179904 bytes |  5000003426 ns

With the patch set:

      16 bytes |         17.051142 MB/s |     85255712 bytes |  5000000854 ns
      32 bytes |         32.695898 MB/s |    163479488 bytes |  5000000544 ns
      64 bytes |         64.490739 MB/s |    322453696 bytes |  5000000954 ns
     128 bytes |        123.285043 MB/s |    616425216 bytes |  5000000201 ns
     256 bytes |        233.434573 MB/s |   1167172864 bytes |  5000000573 ns
     512 bytes |        384.405197 MB/s |   1922025984 bytes |  5000000671 ns
    1024 bytes |        566.313370 MB/s |   2831566848 bytes |  5000001080 ns
    2048 bytes |        744.518042 MB/s |   3722590208 bytes |  5000000926 ns
    4096 bytes |        867.501670 MB/s |   4337508352 bytes |  5000002181 ns

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03 18:05:48 +08:00
Herbert Xu c5f5aeef9b Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux
Merge mainline to pick up c7513c2a27 ("crypto/arm64: aes-ce-gcm -
add missing kernel_neon_begin/end pair").
2018-08-03 17:55:12 +08:00
Christoph Hellwig dd979b4df8 net: simplify sock_poll_wait
The wait_address argument is always directly derived from the filp
argument, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-30 09:10:25 -07:00
Gustavo A. R. Silva a478908993 crypto: rmd320 - use swap macro in rmd320_transform
Make use of the swap macro and remove unnecessary variable *tmp*.
This makes the code easier to read and maintain.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-27 19:28:36 +08:00
Gustavo A. R. Silva d75f482eaf crypto: rmd256 - use swap macro in rmd256_transform
Make use of the swap macro and remove unnecessary variable *tmp*.
This makes the code easier to read and maintain.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-27 19:28:36 +08:00
Stephan Mueller aef66587f1 crypto: ecdh - fix typo of P-192 b value
Fix the b value to be compliant with FIPS 186-4 D.1.2.1. This fix is
required to make sure the SP800-56A public key test passes for P-192.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-20 13:51:22 +08:00
Stephan Mueller c98fae5e29 crypto: dh - update test for public key verification
By adding a zero byte-length for the DH parameter Q value, the public
key verification test is disabled for the given test.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-20 13:51:21 +08:00
Stephan Mueller cf862cbc83 crypto: drbg - eliminate constant reinitialization of SGL
The CTR DRBG requires two SGLs pointing to input/output buffers for the
CTR AES operation. The used SGLs always have only one entry. Thus, the
SGL can be initialized during allocation time, preventing a
re-initialization of the SGLs during each call.

The performance is increased by about 1 to 3 percent depending on the
size of the requested buffer size.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-20 13:51:21 +08:00
Gustavo A. R. Silva 3fd8093b41 crypto: dh - fix memory leak
In case memory resources for *base* were allocated, release them
before return.

Addresses-Coverity-ID: 1471702 ("Resource leak")
Fixes: e3fe0ae129 ("crypto: dh - add public key verification test")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Stephan Müller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-20 13:51:21 +08:00
Linus Torvalds b4394c3435 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fix from Herbert Xu:
 "This fixes an allocation error-path bug in af_alg discovered by
  syzkaller"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: af_alg - Initialize sg_num_bytes in error code path
2018-07-19 07:32:44 -07:00
Matthew Garrett e2861fa716 evm: Don't deadlock if a crypto algorithm is unavailable
When EVM attempts to appraise a file signed with a crypto algorithm the
kernel doesn't have support for, it will cause the kernel to trigger a
module load. If the EVM policy includes appraisal of kernel modules this
will in turn call back into EVM - since EVM is holding a lock until the
crypto initialisation is complete, this triggers a deadlock. Add a
CRYPTO_NOLOAD flag and skip module loading if it's set, and add that flag
in the EVM case in order to fail gracefully with an error message
instead of deadlocking.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18 07:27:22 -04:00
Stephan Mueller 2546da9921 crypto: af_alg - Initialize sg_num_bytes in error code path
The RX SGL in processing is already registered with the RX SGL tracking
list to support proper cleanup. The cleanup code path uses the
sg_num_bytes variable which must therefore be always initialized, even
in the error code path.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Reported-by: syzbot+9c251bdd09f83b92ba95@syzkaller.appspotmail.com
#syz test: https://github.com/google/kmsan.git master
CC: <stable@vger.kernel.org> #4.14
Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-13 18:24:23 +08:00
Gilad Ben-Yossef 7671509593 crypto: testmgr - add hash finup tests
The testmgr hash tests were testing init, digest, update and final
methods but not the finup method. Add a test for this one too.

While doing this, make sure we only run the partial tests once with
the digest tests and skip them with the final and finup tests since
they are the same.

Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09 00:33:35 +08:00
Eric Biggers 3f4a537a26 crypto: aead - remove useless setting of type flags
Some aead algorithms set .cra_flags = CRYPTO_ALG_TYPE_AEAD.  But this is
redundant with the C structure type ('struct aead_alg'), and
crypto_register_aead() already sets the type flag automatically,
clearing any type flag that was already there.  Apparently the useless
assignment has just been copy+pasted around.

So, remove the useless assignment from all the aead algorithms.

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>
2018-07-09 00:30:26 +08:00
Eric Biggers e50944e219 crypto: shash - remove useless setting of type flags
Many shash algorithms set .cra_flags = CRYPTO_ALG_TYPE_SHASH.  But this
is redundant with the C structure type ('struct shash_alg'), and
crypto_register_shash() already sets the type flag automatically,
clearing any type flag that was already there.  Apparently the useless
assignment has just been copy+pasted around.

So, remove the useless assignment from all the shash algorithms.

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>
2018-07-09 00:30:24 +08:00
Eric Biggers e47890163a crypto: sha512_generic - add cra_priority
sha512-generic and sha384-generic had a cra_priority of 0, so it wasn't
possible to have a lower priority SHA-512 or SHA-384 implementation, as
is desired for sha512_mb which is only useful under certain workloads
and is otherwise extremely slow.  Change them to priority 100, which is
the priority used for many of the other generic algorithms.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09 00:30:21 +08:00
Eric Biggers b73b7ac0a7 crypto: sha256_generic - add cra_priority
sha256-generic and sha224-generic had a cra_priority of 0, so it wasn't
possible to have a lower priority SHA-256 or SHA-224 implementation, as
is desired for sha256_mb which is only useful under certain workloads
and is otherwise extremely slow.  Change them to priority 100, which is
the priority used for many of the other generic algorithms.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09 00:30:20 +08:00
Eric Biggers 90ef3e4835 crypto: sha1_generic - add cra_priority
sha1-generic had a cra_priority of 0, so it wasn't possible to have a
lower priority SHA-1 implementation, as is desired for sha1_mb which is
only useful under certain workloads and is otherwise extremely slow.
Change it to priority 100, which is the priority used for many of the
other generic algorithms.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09 00:30:20 +08:00
Stephan Mueller e3fe0ae129 crypto: dh - add public key verification test
According to SP800-56A section 5.6.2.1, the public key to be processed
for the DH operation shall be checked for appropriateness. The check
shall covers the full verification test in case the domain parameter Q
is provided as defined in SP800-56A section 5.6.2.3.1. If Q is not
provided, the partial check according to SP800-56A section 5.6.2.3.2 is
performed.

The full verification test requires the presence of the domain parameter
Q. Thus, the patch adds the support to handle Q. It is permissible to
not provide the Q value as part of the domain parameters. This implies
that the interface is still backwards-compatible where so far only P and
G are to be provided. However, if Q is provided, it is imported.

Without the test, the NIST ACVP testing fails. After adding this check,
the NIST ACVP testing passes. Testing without providing the Q domain
parameter has been performed to verify the interface has not changed.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09 00:26:22 +08:00
Stafford Horne cefd769fd0 crypto: skcipher - Fix -Wstringop-truncation warnings
As of GCC 9.0.0 the build is reporting warnings like:

    crypto/ablkcipher.c: In function ‘crypto_ablkcipher_report’:
    crypto/ablkcipher.c:374:2: warning: ‘strncpy’ specified bound 64 equals destination size [-Wstringop-truncation]
      strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
       sizeof(rblkcipher.geniv));
       ~~~~~~~~~~~~~~~~~~~~~~~~~

This means the strnycpy might create a non null terminated string.  Fix this by
explicitly performing '\0' termination.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Nick Desaulniers <nick.desaulniers@gmail.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09 00:26:20 +08:00