From 8ceee72808d1ae3fb191284afc2257a2be964725 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 27 Mar 2014 18:14:40 +0100 Subject: 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 Acked-by: H. Peter Anvin Fixes: 0e1227d356e9b (crypto: ghash - Add PCLMULQDQ accelerated implementation) Signed-off-by: Herbert Xu --- arch/x86/crypto/ghash-clmulni-intel_glue.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'arch/x86/crypto/ghash-clmulni-intel_glue.c') 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; } -- cgit v1.2.3