Re: [PATCH v4 0/6] crypto: lib/sha256 - cleanup/optimization

From: Herbert Xu
Date: Fri Oct 30 2020 - 02:54:09 EST


On Sun, Oct 25, 2020 at 10:31:13AM -0400, Arvind Sankar wrote:
> Patch 1/2 -- Use memzero_explicit() instead of structure assignment/plain
> memset() to clear sensitive state.
>
> Patch 3 -- Currently the temporary variables used in the generic sha256
> implementation are cleared, but the clearing is optimized away due to
> lack of compiler barriers. Drop the clearing.
>
> The last three patches are optimizations for generic sha256.
>
> v4:
> - Split the first patch into two, the first one just does
> lib/crypto/sha256.c, so that the second one can be applied or dropped
> depending on the outcome of the discussion between Herbert/Eric.
>
> v3:
> - Add some more files to patch 1
> - Reword commit message for patch 2
> - Reformat SHA256_K array
> - Drop v2 patch combining K and W arrays
>
> v2:
> - Add patch to combine K and W arrays, suggested by David
> - Reformat SHA256_ROUND() macro a little
>
> Arvind Sankar (6):
> crypto: lib/sha256 - Use memzero_explicit() for clearing state
> crypto: Use memzero_explicit() for clearing state
> crypto: lib/sha256 - Don't clear temporary variables
> crypto: lib/sha256 - Clear W[] in sha256_update() instead of
> sha256_transform()
> crypto: lib/sha256 - Unroll SHA256 loop 8 times intead of 64
> crypto: lib/sha256 - Unroll LOAD and BLEND loops
>
> arch/arm64/crypto/ghash-ce-glue.c | 2 +-
> arch/arm64/crypto/poly1305-glue.c | 2 +-
> arch/arm64/crypto/sha3-ce-glue.c | 2 +-
> arch/x86/crypto/poly1305_glue.c | 2 +-
> include/crypto/sha1_base.h | 3 +-
> include/crypto/sha256_base.h | 3 +-
> include/crypto/sha512_base.h | 3 +-
> include/crypto/sm3_base.h | 3 +-
> lib/crypto/sha256.c | 212 +++++++++---------------------
> 9 files changed, 76 insertions(+), 156 deletions(-)

All applied. Thanks.
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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