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 17:22:47 +0800 |
| commit | 8ceee72808d1ae3fb191284afc2257a2be964725 (patch) | |
| tree | 30112eda2dac48ea04c9bd035dd918b82a47c2af /arch/x86/crypto | |
| parent | 37b28947170ebe55cb4f689ded5857d943c6578e (diff) | |
| download | linux-8ceee72808d1ae3fb191284afc2257a2be964725.tar.bz2 | |
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')
| -rw-r--r-- | arch/x86/crypto/ghash-clmulni-intel_asm.S | 29 | ||||
| -rw-r--r-- | arch/x86/crypto/ghash-clmulni-intel_glue.c | 14 |
2 files changed, 11 insertions, 32 deletions
diff --git a/arch/x86/crypto/ghash-clmulni-intel_asm.S b/arch/x86/crypto/ghash-clmulni-intel_asm.S index 586f41aac361..185fad49d86f 100644 --- a/arch/x86/crypto/ghash-clmulni-intel_asm.S +++ b/arch/x86/crypto/ghash-clmulni-intel_asm.S @@ -24,10 +24,6 @@ .align 16 .Lbswap_mask: .octa 0x000102030405060708090a0b0c0d0e0f -.Lpoly: - .octa 0xc2000000000000000000000000000001 -.Ltwo_one: - .octa 0x00000001000000000000000000000001 #define DATA %xmm0 #define SHASH %xmm1 @@ -134,28 +130,3 @@ ENTRY(clmul_ghash_update) .Lupdate_just_ret: ret ENDPROC(clmul_ghash_update) - -/* - * void clmul_ghash_setkey(be128 *shash, const u8 *key); - * - * Calculate hash_key << 1 mod poly - */ -ENTRY(clmul_ghash_setkey) - movaps .Lbswap_mask, BSWAP - movups (%rsi), %xmm0 - PSHUFB_XMM BSWAP %xmm0 - movaps %xmm0, %xmm1 - psllq $1, %xmm0 - psrlq $63, %xmm1 - movaps %xmm1, %xmm2 - pslldq $8, %xmm1 - psrldq $8, %xmm2 - por %xmm1, %xmm0 - # reduction - pshufd $0b00100100, %xmm2, %xmm1 - pcmpeqd .Ltwo_one, %xmm1 - pand .Lpoly, %xmm1 - pxor %xmm1, %xmm0 - movups %xmm0, (%rdi) - ret -ENDPROC(clmul_ghash_setkey) 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; } |