From 22240df7ac6d76a271197571a7be45addef2ba15 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sat, 4 Aug 2018 20:46:25 +0200 Subject: [PATCH] crypto: arm64/ghash-ce - implement 4-way aggregation Enhance the GHASH implementation that uses 64-bit polynomial multiplication by adding support for 4-way aggregation. This more than doubles the performance, from 2.4 cycles per byte to 1.1 cpb on Cortex-A53. Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- arch/arm64/crypto/ghash-ce-core.S | 122 +++++++++++++++++++++++++----- arch/arm64/crypto/ghash-ce-glue.c | 71 ++++++++--------- 2 files changed, 142 insertions(+), 51 deletions(-) diff --git a/arch/arm64/crypto/ghash-ce-core.S b/arch/arm64/crypto/ghash-ce-core.S index 344811c6a0ca..1b319b716d5e 100644 --- a/arch/arm64/crypto/ghash-ce-core.S +++ b/arch/arm64/crypto/ghash-ce-core.S @@ -46,6 +46,19 @@ ss3 .req v26 ss4 .req v27 + XL2 .req v8 + XM2 .req v9 + XH2 .req v10 + XL3 .req v11 + XM3 .req v12 + XH3 .req v13 + TT3 .req v14 + TT4 .req v15 + HH .req v16 + HH3 .req v17 + HH4 .req v18 + HH34 .req v19 + .text .arch armv8-a+crypto @@ -134,11 +147,25 @@ .endm .macro __pmull_pre_p64 + add x8, x3, #16 + ld1 {HH.2d-HH4.2d}, [x8] + + trn1 SHASH2.2d, SHASH.2d, HH.2d + trn2 T1.2d, SHASH.2d, HH.2d + eor SHASH2.16b, SHASH2.16b, T1.16b + + trn1 HH34.2d, HH3.2d, HH4.2d + trn2 T1.2d, HH3.2d, HH4.2d + eor HH34.16b, HH34.16b, T1.16b + movi MASK.16b, #0xe1 shl MASK.2d, MASK.2d, #57 .endm .macro __pmull_pre_p8 + ext SHASH2.16b, SHASH.16b, SHASH.16b, #8 + eor SHASH2.16b, SHASH2.16b, SHASH.16b + // k00_16 := 0x0000000000000000_000000000000ffff // k32_48 := 0x00000000ffffffff_0000ffffffffffff movi k32_48.2d, #0xffffffff @@ -215,8 +242,6 @@ .macro __pmull_ghash, pn ld1 {SHASH.2d}, [x3] ld1 {XL.2d}, [x1] - ext SHASH2.16b, SHASH.16b, SHASH.16b, #8 - eor SHASH2.16b, SHASH2.16b, SHASH.16b __pmull_pre_\pn @@ -224,12 +249,79 @@ cbz x4, 0f ld1 {T1.2d}, [x4] mov x4, xzr - b 1f + b 3f -0: ld1 {T1.2d}, [x2], #16 +0: .ifc \pn, p64 + tbnz w0, #0, 2f // skip until #blocks is a + tbnz w0, #1, 2f // round multiple of 4 + +1: ld1 {XM3.16b-TT4.16b}, [x2], #64 + + sub w0, w0, #4 + + rev64 T1.16b, XM3.16b + rev64 T2.16b, XH3.16b + rev64 TT4.16b, TT4.16b + rev64 TT3.16b, TT3.16b + + ext IN1.16b, TT4.16b, TT4.16b, #8 + ext XL3.16b, TT3.16b, TT3.16b, #8 + + eor TT4.16b, TT4.16b, IN1.16b + pmull2 XH2.1q, SHASH.2d, IN1.2d // a1 * b1 + pmull XL2.1q, SHASH.1d, IN1.1d // a0 * b0 + pmull XM2.1q, SHASH2.1d, TT4.1d // (a1 + a0)(b1 + b0) + + eor TT3.16b, TT3.16b, XL3.16b + pmull2 XH3.1q, HH.2d, XL3.2d // a1 * b1 + pmull XL3.1q, HH.1d, XL3.1d // a0 * b0 + pmull2 XM3.1q, SHASH2.2d, TT3.2d // (a1 + a0)(b1 + b0) + + ext IN1.16b, T2.16b, T2.16b, #8 + eor XL2.16b, XL2.16b, XL3.16b + eor XH2.16b, XH2.16b, XH3.16b + eor XM2.16b, XM2.16b, XM3.16b + + eor T2.16b, T2.16b, IN1.16b + pmull2 XH3.1q, HH3.2d, IN1.2d // a1 * b1 + pmull XL3.1q, HH3.1d, IN1.1d // a0 * b0 + pmull XM3.1q, HH34.1d, T2.1d // (a1 + a0)(b1 + b0) + + eor XL2.16b, XL2.16b, XL3.16b + eor XH2.16b, XH2.16b, XH3.16b + eor XM2.16b, XM2.16b, XM3.16b + + ext IN1.16b, T1.16b, T1.16b, #8 + ext TT3.16b, XL.16b, XL.16b, #8 + eor XL.16b, XL.16b, IN1.16b + eor T1.16b, T1.16b, TT3.16b + + pmull2 XH.1q, HH4.2d, XL.2d // a1 * b1 + eor T1.16b, T1.16b, XL.16b + pmull XL.1q, HH4.1d, XL.1d // a0 * b0 + pmull2 XM.1q, HH34.2d, T1.2d // (a1 + a0)(b1 + b0) + + eor XL.16b, XL.16b, XL2.16b + eor XH.16b, XH.16b, XH2.16b + eor XM.16b, XM.16b, XM2.16b + + eor T2.16b, XL.16b, XH.16b + ext T1.16b, XL.16b, XH.16b, #8 + eor XM.16b, XM.16b, T2.16b + + __pmull_reduce_p64 + + eor T2.16b, T2.16b, XH.16b + eor XL.16b, XL.16b, T2.16b + + cbz w0, 5f + b 1b + .endif + +2: ld1 {T1.2d}, [x2], #16 sub w0, w0, #1 -1: /* multiply XL by SHASH in GF(2^128) */ +3: /* multiply XL by SHASH in GF(2^128) */ CPU_LE( rev64 T1.16b, T1.16b ) ext T2.16b, XL.16b, XL.16b, #8 @@ -242,7 +334,7 @@ CPU_LE( rev64 T1.16b, T1.16b ) __pmull_\pn XL, XL, SHASH // a0 * b0 __pmull_\pn XM, T1, SHASH2 // (a1 + a0)(b1 + b0) - eor T2.16b, XL.16b, XH.16b +4: eor T2.16b, XL.16b, XH.16b ext T1.16b, XL.16b, XH.16b, #8 eor XM.16b, XM.16b, T2.16b @@ -253,7 +345,7 @@ CPU_LE( rev64 T1.16b, T1.16b ) cbnz w0, 0b - st1 {XL.2d}, [x1] +5: st1 {XL.2d}, [x1] ret .endm @@ -269,14 +361,10 @@ ENTRY(pmull_ghash_update_p8) __pmull_ghash p8 ENDPROC(pmull_ghash_update_p8) - KS0 .req v8 - KS1 .req v9 - INP0 .req v10 - INP1 .req v11 - HH .req v12 - XL2 .req v13 - XM2 .req v14 - XH2 .req v15 + KS0 .req v12 + KS1 .req v13 + INP0 .req v14 + INP1 .req v15 .macro load_round_keys, rounds, rk cmp \rounds, #12 @@ -310,8 +398,8 @@ ENDPROC(pmull_ghash_update_p8) .endm .macro pmull_gcm_do_crypt, enc - ld1 {HH.2d}, [x4], #16 - ld1 {SHASH.2d}, [x4] + ld1 {SHASH.2d}, [x4], #16 + ld1 {HH.2d}, [x4] ld1 {XL.2d}, [x1] ldr x8, [x5, #8] // load lower counter diff --git a/arch/arm64/crypto/ghash-ce-glue.c b/arch/arm64/crypto/ghash-ce-glue.c index 3c2c446dc96c..6e9f33d14930 100644 --- a/arch/arm64/crypto/ghash-ce-glue.c +++ b/arch/arm64/crypto/ghash-ce-glue.c @@ -33,9 +33,12 @@ MODULE_ALIAS_CRYPTO("ghash"); #define GCM_IV_SIZE 12 struct ghash_key { - u64 a; - u64 b; - be128 k; + u64 h[2]; + u64 h2[2]; + u64 h3[2]; + u64 h4[2]; + + be128 k; }; struct ghash_desc_ctx { @@ -46,7 +49,6 @@ struct ghash_desc_ctx { struct gcm_aes_ctx { struct crypto_aes_ctx aes_key; - u64 h2[2]; struct ghash_key ghash_key; }; @@ -63,11 +65,12 @@ static void (*pmull_ghash_update)(int blocks, u64 dg[], const char *src, const char *head); asmlinkage void pmull_gcm_encrypt(int blocks, u64 dg[], u8 dst[], - const u8 src[], u64 const *k, u8 ctr[], - u32 const rk[], int rounds, u8 ks[]); + const u8 src[], struct ghash_key const *k, + u8 ctr[], u32 const rk[], int rounds, + u8 ks[]); asmlinkage void pmull_gcm_decrypt(int blocks, u64 dg[], u8 dst[], - const u8 src[], u64 const *k, + const u8 src[], struct ghash_key const *k, u8 ctr[], u32 const rk[], int rounds); asmlinkage void pmull_gcm_encrypt_block(u8 dst[], u8 const src[], @@ -174,23 +177,36 @@ static int ghash_final(struct shash_desc *desc, u8 *dst) return 0; } +static void ghash_reflect(u64 h[], const be128 *k) +{ + u64 carry = be64_to_cpu(k->a) & BIT(63) ? 1 : 0; + + h[0] = (be64_to_cpu(k->b) << 1) | carry; + h[1] = (be64_to_cpu(k->a) << 1) | (be64_to_cpu(k->b) >> 63); + + if (carry) + h[1] ^= 0xc200000000000000UL; +} + static int __ghash_setkey(struct ghash_key *key, const u8 *inkey, unsigned int keylen) { - u64 a, b; + be128 h; /* needed for the fallback */ memcpy(&key->k, inkey, GHASH_BLOCK_SIZE); - /* perform multiplication by 'x' in GF(2^128) */ - b = get_unaligned_be64(inkey); - a = get_unaligned_be64(inkey + 8); + ghash_reflect(key->h, &key->k); - key->a = (a << 1) | (b >> 63); - key->b = (b << 1) | (a >> 63); + h = key->k; + gf128mul_lle(&h, &key->k); + ghash_reflect(key->h2, &h); - if (b >> 63) - key->b ^= 0xc200000000000000UL; + gf128mul_lle(&h, &key->k); + ghash_reflect(key->h3, &h); + + gf128mul_lle(&h, &key->k); + ghash_reflect(key->h4, &h); return 0; } @@ -240,8 +256,7 @@ static int gcm_setkey(struct crypto_aead *tfm, const u8 *inkey, unsigned int keylen) { struct gcm_aes_ctx *ctx = crypto_aead_ctx(tfm); - be128 h1, h2; - u8 *key = (u8 *)&h1; + u8 key[GHASH_BLOCK_SIZE]; int ret; ret = crypto_aes_expand_key(&ctx->aes_key, inkey, keylen); @@ -253,19 +268,7 @@ static int gcm_setkey(struct crypto_aead *tfm, const u8 *inkey, __aes_arm64_encrypt(ctx->aes_key.key_enc, key, (u8[AES_BLOCK_SIZE]){}, num_rounds(&ctx->aes_key)); - __ghash_setkey(&ctx->ghash_key, key, sizeof(be128)); - - /* calculate H^2 (used for 2-way aggregation) */ - h2 = h1; - gf128mul_lle(&h2, &h1); - - ctx->h2[0] = (be64_to_cpu(h2.b) << 1) | (be64_to_cpu(h2.a) >> 63); - ctx->h2[1] = (be64_to_cpu(h2.a) << 1) | (be64_to_cpu(h2.b) >> 63); - - if (be64_to_cpu(h2.a) >> 63) - ctx->h2[1] ^= 0xc200000000000000UL; - - return 0; + return __ghash_setkey(&ctx->ghash_key, key, sizeof(be128)); } static int gcm_setauthsize(struct crypto_aead *tfm, unsigned int authsize) @@ -401,8 +404,8 @@ static int gcm_encrypt(struct aead_request *req) kernel_neon_begin(); pmull_gcm_encrypt(blocks, dg, walk.dst.virt.addr, - walk.src.virt.addr, ctx->h2, iv, - rk, nrounds, ks); + walk.src.virt.addr, &ctx->ghash_key, + iv, rk, nrounds, ks); kernel_neon_end(); err = skcipher_walk_done(&walk, @@ -512,8 +515,8 @@ static int gcm_decrypt(struct aead_request *req) kernel_neon_begin(); pmull_gcm_decrypt(blocks, dg, walk.dst.virt.addr, - walk.src.virt.addr, ctx->h2, iv, - rk, nrounds); + walk.src.virt.addr, &ctx->ghash_key, + iv, rk, nrounds); /* check if this is the final iteration of the loop */ if (rem < (2 * AES_BLOCK_SIZE)) {