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>
This function returns a string with the currently in-use implementation
of the crc32c algorithm, i.e crc32c-generic (for unoptimised, generic
implementation) or crc32c-intel for the sse optimised version. This
will be used by btrfs.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
[ use crypto_shash_driver_name as suggested by Herbert ]
Signed-off-by: David Sterba <dsterba@suse.com>
On sparc, if we have an alloca() like situation, as is the case with
SHASH_DESC_ON_STACK(), we can end up referencing deallocated stack
memory. The result can be that the value is clobbered if a trap
or interrupt arrives at just the right instruction.
It only occurs if the function ends returning a value from that
alloca() area and that value can be placed into the return value
register using a single instruction.
For example, in lib/libcrc32c.c:crc32c() we end up with a return
sequence like:
return %i7+8
lduw [%o5+16], %o0 ! MEM[(u32 *)__shash_desc.1_10 + 16B],
%o5 holds the base of the on-stack area allocated for the shash
descriptor. But the return released the stack frame and the
register window.
So if an intererupt arrives between 'return' and 'lduw', then
the value read at %o5+16 can be corrupted.
Add a data compiler barrier to work around this problem. This is
exactly what the gcc fix will end up doing as well, and it absolutely
should not change the code generated for other cpus (unless gcc
on them has the same bug :-)
With crucial insight from Eric Sandeen.
Cc: <stable@vger.kernel.org>
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto fixes from Herbert Xu:
"This fixes the following issues:
API:
- A large number of bug fixes for the af_alg interface, credit goes
to Dmitry Vyukov for discovering and reporting these issues.
Algorithms:
- sw842 needs to select crc32.
- The soft dependency on crc32c is now in the correct spot.
Drivers:
- The atmel AES driver needs HAS_DMA.
- The atmel AES driver was a missing break statement, fortunately
it's only a debug function.
- A number of bug fixes for the Intel qat driver"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (24 commits)
crypto: algif_skcipher - sendmsg SG marking is off by one
crypto: crc32c - Fix crc32c soft dependency
crypto: algif_skcipher - Load TX SG list after waiting
crypto: atmel-aes - Add missing break to atmel_aes_reg_name
crypto: algif_skcipher - Fix race condition in skcipher_check_key
crypto: algif_hash - Fix race condition in hash_check_key
crypto: CRYPTO_DEV_ATMEL_AES should depend on HAS_DMA
lib: sw842: select crc32
crypto: af_alg - Forbid bind(2) when nokey child sockets are present
crypto: algif_skcipher - Remove custom release parent function
crypto: algif_hash - Remove custom release parent function
crypto: af_alg - Allow af_af_alg_release_parent to be called on nokey path
crypto: qat - update init_esram for C3xxx dev type
crypto: qat - fix timeout issues
crypto: qat - remove to call get_sram_bar_id for qat_c3xxx
crypto: algif_skcipher - Add key check exception for cipher_null
crypto: skcipher - Add crypto_skcipher_has_setkey
crypto: algif_hash - Require setkey before accept(2)
crypto: hash - Add crypto_ahash_has_setkey
crypto: algif_skcipher - Add nokey compatibility path
...
Fix the following build warning:
lib/libcrc32c.c:42:5: warning: no previous prototype for "crc32c" [-Wmissing-prototypes]
u32 crc32c(u32 crc, const void *address, unsigned int length)
^
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I don't think it makes sense for a module to have a soft dependency
on itself. This seems quite cyclic by nature and I can't see what
purpose it could serve.
OTOH libcrc32c calls crypto_alloc_shash("crc32c", 0, 0) so it pretty
much assumes that some incarnation of the "crc32c" hash algorithm has
been loaded. Therefore it makes sense to have the soft dependency
there (as crc-t10dif does.)
Cc: stable@vger.kernel.org
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch allocates the appropriate amount of memory
using a char array using the SHASH_DESC_ON_STACK macro.
The new code can be compiled with both gcc and clang.
Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: pageexec@freemail.hu
Cc: "David S. Miller" <davem@davemloft.net>
This patch swaps the role of libcrc32c and crc32c. Previously
the implementation was in libcrc32c and crc32c was a wrapper.
Now the code is in crc32c and libcrc32c just calls the crypto
layer.
The reason for the change is to tap into the algorithm selection
capability of the crypto API so that optimised implementations
such as the one utilising Intel's CRC32C instruction can be
used where available.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto/crc32.c:chksum_final() is computing the digest as
*(__le32 *)out = ~cpu_to_le32(mctx->crc);
so the low-level crc32c_le routines should just keep
the crc in cpu order, otherwise it is getting swabbed
one too many times on big-endian machines.
Signed-off-by: Benny Halevy <bhalevy@fs1.bhalevy.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
To be consistent with the use of attributes in the rest of the kernel
replace all use of __attribute_pure__ with __pure and delete the definition
of __attribute_pure__.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Eric Biggers