diff options
author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2014-03-27 18:14:40 +0100 |
---|---|---|
committer | Herbert Xu <herbert@gondor.apana.org.au> | 2014-04-01 11:22:47 +0200 |
commit | 8ceee72808d1ae3fb191284afc2257a2be964725 (patch) | |
tree | 30112eda2dac48ea04c9bd035dd918b82a47c2af /arch/x86/crypto/ghash-clmulni-intel_glue.c | |
parent | crypto: x86/sha1 - reduce size of the AVX2 asm implementation (diff) | |
download | linux-8ceee72808d1ae3fb191284afc2257a2be964725.tar.xz linux-8ceee72808d1ae3fb191284afc2257a2be964725.zip |
crypto: ghash-clmulni-intel - use C implementation for setkey()
The GHASH setkey() function uses SSE registers but fails to call
kernel_fpu_begin()/kernel_fpu_end(). Instead of adding these calls, and
then having to deal with the restriction that they cannot be called from
interrupt context, move the setkey() implementation to the C domain.
Note that setkey() does not use any particular SSE features and is not
expected to become a performance bottleneck.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Fixes: 0e1227d356e9b (crypto: ghash - Add PCLMULQDQ accelerated implementation)
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'arch/x86/crypto/ghash-clmulni-intel_glue.c')
-rw-r--r-- | arch/x86/crypto/ghash-clmulni-intel_glue.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/arch/x86/crypto/ghash-clmulni-intel_glue.c b/arch/x86/crypto/ghash-clmulni-intel_glue.c index 6759dd1135be..d785cf2c529c 100644 --- a/arch/x86/crypto/ghash-clmulni-intel_glue.c +++ b/arch/x86/crypto/ghash-clmulni-intel_glue.c @@ -30,8 +30,6 @@ void clmul_ghash_mul(char *dst, const be128 *shash); void clmul_ghash_update(char *dst, const char *src, unsigned int srclen, const be128 *shash); -void clmul_ghash_setkey(be128 *shash, const u8 *key); - struct ghash_async_ctx { struct cryptd_ahash *cryptd_tfm; }; @@ -58,13 +56,23 @@ static int ghash_setkey(struct crypto_shash *tfm, const u8 *key, unsigned int keylen) { struct ghash_ctx *ctx = crypto_shash_ctx(tfm); + be128 *x = (be128 *)key; + u64 a, b; if (keylen != GHASH_BLOCK_SIZE) { crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); return -EINVAL; } - clmul_ghash_setkey(&ctx->shash, key); + /* perform multiplication by 'x' in GF(2^128) */ + a = be64_to_cpu(x->a); + b = be64_to_cpu(x->b); + + ctx->shash.a = (__be64)((b << 1) | (a >> 63)); + ctx->shash.b = (__be64)((a << 1) | (b >> 63)); + + if (a >> 63) + ctx->shash.b ^= cpu_to_be64(0xc2); return 0; } |