As reported by kbuild test robot, the optimized SHA3 C implementation
compiles to mn10300 code that uses a disproportionate amount of stack
space, i.e.,
crypto/sha3_generic.c: In function 'keccakf':
crypto/sha3_generic.c:147:1: warning: the frame size of 1232 bytes is larger than 1024 bytes [-Wframe-larger-than=]
As kindly diagnosed by Arnd, this does not only occur when building for
the mn10300 architecture (which is what the report was about) but also
for h8300, and builds for other 32-bit architectures show an increase in
stack space utilization as well.
Given that SHA3 operates on 64-bit quantities, and keeps a state matrix
of 25 64-bit words, it is not surprising that 32-bit architectures with
few general purpose registers are impacted the most by this, and it is
therefore reasonable to implement a workaround that distinguishes between
32-bit and 64-bit architectures.
Arnd figured out that taking the round calculation out of the loop, and
inlining it explicitly but only on 64-bit architectures preserves most
of the performance gain achieved by the rewrite, and also gets rid of
the excessive use of stack space.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
To allow accelerated implementations to fall back to the generic
routines, e.g., in contexts where a SIMD based implementation is
not allowed to run, expose the generic SHA3 init/update/final
routines to other modules.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In preparation of exposing the generic SHA3 implementation to other
versions as a fallback, simplify the code, and remove an inconsistency
in the output handling (endian swabbing rsizw words of state before
writing the output does not make sense)
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The way the KECCAK transform is currently coded involves many references
into the state array using indexes that are calculated at runtime using
simple but non-trivial arithmetic. This forces the compiler to treat the
state matrix as an array in memory rather than keep it in registers,
which results in poor performance.
So instead, let's rephrase the algorithm using fixed array indexes only.
This helps the compiler keep the state matrix in registers, resulting
in the following speedup (SHA3-256 performance in cycles per byte):
before after speedup
Intel Core i7 @ 2.0 GHz (2.9 turbo) 100.6 35.7 2.8x
Cortex-A57 @ 2.0 GHz (64-bit mode) 101.6 12.7 8.0x
Cortex-A53 @ 1.0 GHz 224.4 15.8 14.2x
Cortex-A57 @ 2.0 GHz (32-bit mode) 201.8 63.0 3.2x
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Ensure that the input is byte swabbed before injecting it into the
SHA3 transform. Use the get_unaligned() accessor for this so that
we don't perform unaligned access inadvertently on architectures
that do not support that.
Cc: <stable@vger.kernel.org>
Fixes: 53964b9ee6 ("crypto: sha3 - Add SHA-3 hash algorithm")
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On 32-bit (e.g. with m68k-linux-gnu-gcc-4.1):
crypto/sha3_generic.c:27: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:28: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:29: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:29: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:31: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:31: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:32: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:32: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:32: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:33: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:33: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:34: warning: integer constant is too large for ‘long’ type
crypto/sha3_generic.c:34: warning: integer constant is too large for ‘long’ type
Fixes: 53964b9ee6 ("crypto: sha3 - Add SHA-3 hash algorithm")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the implementation of SHA3 algorithm
in software and it's based on original implementation
pushed in patch https://lwn.net/Articles/518415/ with
additional changes to match the padding rules specified
in SHA-3 specification.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Raveendra Padasalagi <raveendra.padasalagi@broadcom.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
David Howells