crypto/fipsmodule/modes/gcm.cc.inc - boringssl - Git at Google

 /*
  * Copyright 2010-2016 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
  * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html
  */

 #include <openssl/base.h>

 #include <string.h>

 #include <openssl/mem.h>

 #include "../../internal.h"
 #include "../aes/internal.h"
 #include "internal.h"


 // kSizeTWithoutLower4Bits is a mask that can be used to zero the lower four
 // bits of a |size_t|.
 static const size_t kSizeTWithoutLower4Bits = (size_t) -16;


 #define GCM_MUL(key, ctx, Xi) gcm_gmult_nohw((ctx)->Xi, (key)->Htable)
 #define GHASH(key, ctx, in, len) \
   gcm_ghash_nohw((ctx)->Xi, (key)->Htable, in, len)
 // GHASH_CHUNK is "stride parameter" missioned to mitigate cache
 // trashing effect. In other words idea is to hash data while it's
 // still in L1 cache after encryption pass...
 #define GHASH_CHUNK (3 * 1024)

 #if defined(GHASH_ASM_X86_64) || defined(GHASH_ASM_X86)
 static inline void gcm_reduce_1bit(u128 *V) {
   if (sizeof(crypto_word_t) == 8) {
     uint64_t T = UINT64_C(0xe100000000000000) & (0 - (V->hi & 1));
     V->hi = (V->lo << 63) | (V->hi >> 1);
     V->lo = (V->lo >> 1) ^ T;
   } else {
     uint32_t T = 0xe1000000U & (0 - (uint32_t)(V->hi & 1));
     V->hi = (V->lo << 63) | (V->hi >> 1);
     V->lo = (V->lo >> 1) ^ ((uint64_t)T << 32);
   }
 }

 void gcm_init_ssse3(u128 Htable[16], const uint64_t H[2]) {
   Htable[0].hi = 0;
   Htable[0].lo = 0;
   u128 V;
   V.hi = H[1];
   V.lo = H[0];

   Htable[8] = V;
   gcm_reduce_1bit(&V);
   Htable[4] = V;
   gcm_reduce_1bit(&V);
   Htable[2] = V;
   gcm_reduce_1bit(&V);
   Htable[1] = V;
   Htable[3].hi = V.hi ^ Htable[2].hi, Htable[3].lo = V.lo ^ Htable[2].lo;
   V = Htable[4];
   Htable[5].hi = V.hi ^ Htable[1].hi, Htable[5].lo = V.lo ^ Htable[1].lo;
   Htable[6].hi = V.hi ^ Htable[2].hi, Htable[6].lo = V.lo ^ Htable[2].lo;
   Htable[7].hi = V.hi ^ Htable[3].hi, Htable[7].lo = V.lo ^ Htable[3].lo;
   V = Htable[8];
   Htable[9].hi = V.hi ^ Htable[1].hi, Htable[9].lo = V.lo ^ Htable[1].lo;
   Htable[10].hi = V.hi ^ Htable[2].hi, Htable[10].lo = V.lo ^ Htable[2].lo;
   Htable[11].hi = V.hi ^ Htable[3].hi, Htable[11].lo = V.lo ^ Htable[3].lo;
   Htable[12].hi = V.hi ^ Htable[4].hi, Htable[12].lo = V.lo ^ Htable[4].lo;
   Htable[13].hi = V.hi ^ Htable[5].hi, Htable[13].lo = V.lo ^ Htable[5].lo;
   Htable[14].hi = V.hi ^ Htable[6].hi, Htable[14].lo = V.lo ^ Htable[6].lo;
   Htable[15].hi = V.hi ^ Htable[7].hi, Htable[15].lo = V.lo ^ Htable[7].lo;

   // Treat |Htable| as a 16x16 byte table and transpose it. Thus, Htable[i]
   // contains the i'th byte of j*H for all j.
   uint8_t *Hbytes = (uint8_t *)Htable;
   for (int i = 0; i < 16; i++) {
     for (int j = 0; j < i; j++) {
       uint8_t tmp = Hbytes[16*i + j];
       Hbytes[16*i + j] = Hbytes[16*j + i];
       Hbytes[16*j + i] = tmp;
     }
   }
 }
 #endif  // GHASH_ASM_X86_64 || GHASH_ASM_X86

 #ifdef GCM_FUNCREF
 #undef GCM_MUL
 #define GCM_MUL(key, ctx, Xi) (*gcm_gmult_p)((ctx)->Xi, (key)->Htable)
 #undef GHASH
 #define GHASH(key, ctx, in, len) \
   (*gcm_ghash_p)((ctx)->Xi, (key)->Htable, in, len)
 #endif  // GCM_FUNCREF

 #if defined(HW_GCM) && defined(OPENSSL_X86_64)
 static size_t hw_gcm_encrypt(const uint8_t *in, uint8_t *out, size_t len,
                              const AES_KEY *key, uint8_t ivec[16],
                              uint8_t Xi[16], const u128 Htable[16],
                              enum gcm_impl_t impl) {
   switch (impl) {
     case gcm_x86_vaes_avx10_256:
       len &= kSizeTWithoutLower4Bits;
       aes_gcm_enc_update_vaes_avx10_256(in, out, len, key, ivec, Htable, Xi);
       CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
       return len;
     case gcm_x86_vaes_avx10_512:
       len &= kSizeTWithoutLower4Bits;
       aes_gcm_enc_update_vaes_avx10_512(in, out, len, key, ivec, Htable, Xi);
       CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
       return len;
     default:
       return aesni_gcm_encrypt(in, out, len, key, ivec, Htable, Xi);
   }
 }

 static size_t hw_gcm_decrypt(const uint8_t *in, uint8_t *out, size_t len,
                              const AES_KEY *key, uint8_t ivec[16],
                              uint8_t Xi[16], const u128 Htable[16],
                              enum gcm_impl_t impl) {
   switch (impl) {
     case gcm_x86_vaes_avx10_256:
       len &= kSizeTWithoutLower4Bits;
       aes_gcm_dec_update_vaes_avx10_256(in, out, len, key, ivec, Htable, Xi);
       CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
       return len;
     case gcm_x86_vaes_avx10_512:
       len &= kSizeTWithoutLower4Bits;
       aes_gcm_dec_update_vaes_avx10_512(in, out, len, key, ivec, Htable, Xi);
       CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
       return len;
     default:
       return aesni_gcm_decrypt(in, out, len, key, ivec, Htable, Xi);
   }
 }
 #endif  // HW_GCM && X86_64

 #if defined(HW_GCM) && defined(OPENSSL_AARCH64)

 static size_t hw_gcm_encrypt(const uint8_t *in, uint8_t *out, size_t len,
                              const AES_KEY *key, uint8_t ivec[16],
                              uint8_t Xi[16], const u128 Htable[16],
                              enum gcm_impl_t impl) {
   const size_t len_blocks = len & kSizeTWithoutLower4Bits;
   if (!len_blocks) {
     return 0;
   }
   aes_gcm_enc_kernel(in, len_blocks * 8, out, Xi, ivec, key, Htable);
   return len_blocks;
 }

 static size_t hw_gcm_decrypt(const uint8_t *in, uint8_t *out, size_t len,
                              const AES_KEY *key, uint8_t ivec[16],
                              uint8_t Xi[16], const u128 Htable[16],
                              enum gcm_impl_t impl) {
   const size_t len_blocks = len & kSizeTWithoutLower4Bits;
   if (!len_blocks) {
     return 0;
   }
   aes_gcm_dec_kernel(in, len_blocks * 8, out, Xi, ivec, key, Htable);
   return len_blocks;
 }

 #endif  // HW_GCM && AARCH64

 void CRYPTO_ghash_init(gmult_func *out_mult, ghash_func *out_hash,
                        u128 out_table[16], const uint8_t gcm_key[16]) {
   // H is passed to |gcm_init_*| as a pair of byte-swapped, 64-bit values.
   uint64_t H[2] = {CRYPTO_load_u64_be(gcm_key),
                    CRYPTO_load_u64_be(gcm_key + 8)};

 #if defined(GHASH_ASM_X86_64)
   if (crypto_gcm_clmul_enabled()) {
     if (CRYPTO_is_AVX512BW_capable() && CRYPTO_is_AVX512VL_capable() &&
         CRYPTO_is_VPCLMULQDQ_capable() && CRYPTO_is_BMI2_capable()) {
       gcm_init_vpclmulqdq_avx10(out_table, H);
       *out_mult = gcm_gmult_vpclmulqdq_avx10;
       if (CRYPTO_cpu_avoid_zmm_registers()) {
         *out_hash = gcm_ghash_vpclmulqdq_avx10_256;
       } else {
         *out_hash = gcm_ghash_vpclmulqdq_avx10_512;
       }
       return;
     }
     if (CRYPTO_is_AVX_capable() && CRYPTO_is_MOVBE_capable()) {
       gcm_init_avx(out_table, H);
       *out_mult = gcm_gmult_avx;
       *out_hash = gcm_ghash_avx;
       return;
     }
     gcm_init_clmul(out_table, H);
     *out_mult = gcm_gmult_clmul;
     *out_hash = gcm_ghash_clmul;
     return;
   }
   if (CRYPTO_is_SSSE3_capable()) {
     gcm_init_ssse3(out_table, H);
     *out_mult = gcm_gmult_ssse3;
     *out_hash = gcm_ghash_ssse3;
     return;
   }
 #elif defined(GHASH_ASM_X86)
   if (crypto_gcm_clmul_enabled()) {
     gcm_init_clmul(out_table, H);
     *out_mult = gcm_gmult_clmul;
     *out_hash = gcm_ghash_clmul;
     return;
   }
   if (CRYPTO_is_SSSE3_capable()) {
     gcm_init_ssse3(out_table, H);
     *out_mult = gcm_gmult_ssse3;
     *out_hash = gcm_ghash_ssse3;
     return;
   }
 #elif defined(GHASH_ASM_ARM)
   if (gcm_pmull_capable()) {
     gcm_init_v8(out_table, H);
     *out_mult = gcm_gmult_v8;
     *out_hash = gcm_ghash_v8;
     return;
   }

   if (gcm_neon_capable()) {
     gcm_init_neon(out_table, H);
     *out_mult = gcm_gmult_neon;
     *out_hash = gcm_ghash_neon;
     return;
   }
 #endif

   gcm_init_nohw(out_table, H);
   *out_mult = gcm_gmult_nohw;
   *out_hash = gcm_ghash_nohw;
 }

 void CRYPTO_gcm128_init_aes_key(GCM128_KEY *gcm_key, const uint8_t *key,
                                 size_t key_bytes) {
   switch (key_bytes) {
     case 16:
       boringssl_fips_inc_counter(fips_counter_evp_aes_128_gcm);
       break;

     case 32:
       boringssl_fips_inc_counter(fips_counter_evp_aes_256_gcm);
       break;
   }

   OPENSSL_memset(gcm_key, 0, sizeof(*gcm_key));
   int is_hwaes;
   gcm_key->ctr = aes_ctr_set_key(&gcm_key->aes, &is_hwaes, &gcm_key->block, key,
                                  key_bytes);

   uint8_t ghash_key[16];
   OPENSSL_memset(ghash_key, 0, sizeof(ghash_key));
   gcm_key->block(ghash_key, ghash_key, &gcm_key->aes);

   CRYPTO_ghash_init(&gcm_key->gmult, &gcm_key->ghash, gcm_key->Htable,
                     ghash_key);

 #if !defined(OPENSSL_NO_ASM)
 #if defined(OPENSSL_X86_64)
   if (gcm_key->ghash == gcm_ghash_vpclmulqdq_avx10_256 &&
       CRYPTO_is_VAES_capable()) {
     gcm_key->impl = gcm_x86_vaes_avx10_256;
   } else if (gcm_key->ghash == gcm_ghash_vpclmulqdq_avx10_512 &&
              CRYPTO_is_VAES_capable()) {
     gcm_key->impl = gcm_x86_vaes_avx10_512;
   } else if (gcm_key->ghash == gcm_ghash_avx && is_hwaes) {
     gcm_key->impl = gcm_x86_aesni;
   }
 #elif defined(OPENSSL_AARCH64)
   if (gcm_pmull_capable() && is_hwaes) {
     gcm_key->impl = gcm_arm64_aes;
   }
 #endif
 #endif
 }

 void CRYPTO_gcm128_init_ctx(const GCM128_KEY *key, GCM128_CONTEXT *ctx,
                             const uint8_t *iv, size_t iv_len) {
 #ifdef GCM_FUNCREF
   void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
 #endif

   OPENSSL_memset(&ctx->Yi, 0, sizeof(ctx->Yi));
   OPENSSL_memset(&ctx->Xi, 0, sizeof(ctx->Xi));
   ctx->len.aad = 0;
   ctx->len.msg = 0;
   ctx->ares = 0;
   ctx->mres = 0;

   uint32_t ctr;
   if (iv_len == 12) {
     OPENSSL_memcpy(ctx->Yi, iv, 12);
     ctx->Yi[15] = 1;
     ctr = 1;
   } else {
     uint64_t len0 = iv_len;

     while (iv_len >= 16) {
       CRYPTO_xor16(ctx->Yi, ctx->Yi, iv);
       GCM_MUL(key, ctx, Yi);
       iv += 16;
       iv_len -= 16;
     }
     if (iv_len) {
       for (size_t i = 0; i < iv_len; ++i) {
         ctx->Yi[i] ^= iv[i];
       }
       GCM_MUL(key, ctx, Yi);
     }

     uint8_t len_block[16];
     OPENSSL_memset(len_block, 0, 8);
     CRYPTO_store_u64_be(len_block + 8, len0 << 3);
     CRYPTO_xor16(ctx->Yi, ctx->Yi, len_block);

     GCM_MUL(key, ctx, Yi);
     ctr = CRYPTO_load_u32_be(ctx->Yi + 12);
   }

   key->block(ctx->Yi, ctx->EK0, &key->aes);
   ++ctr;
   CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
 }

 int CRYPTO_gcm128_aad(const GCM128_KEY *key, GCM128_CONTEXT *ctx,
                       const uint8_t *aad, size_t aad_len) {
 #ifdef GCM_FUNCREF
   void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
   void (*gcm_ghash_p)(uint8_t Xi[16], const u128 Htable[16], const uint8_t *inp,
                       size_t len) = key->ghash;
 #endif

   if (ctx->len.msg != 0) {
     // The caller must have finished the AAD before providing other input.
     return 0;
   }

   uint64_t alen = ctx->len.aad + aad_len;
   if (alen > (UINT64_C(1) << 61) || (sizeof(aad_len) == 8 && alen < aad_len)) {
     return 0;
   }
   ctx->len.aad = alen;

   unsigned n = ctx->ares;
   if (n) {
     while (n && aad_len) {
       ctx->Xi[n] ^= *(aad++);
       --aad_len;
       n = (n + 1) % 16;
     }
     if (n == 0) {
       GCM_MUL(key, ctx, Xi);
     } else {
       ctx->ares = n;
       return 1;
     }
   }

   // Process a whole number of blocks.
   size_t len_blocks = aad_len & kSizeTWithoutLower4Bits;
   if (len_blocks != 0) {
     GHASH(key, ctx, aad, len_blocks);
     aad += len_blocks;
     aad_len -= len_blocks;
   }

   // Process the remainder.
   if (aad_len != 0) {
     n = (unsigned int)aad_len;
     for (size_t i = 0; i < aad_len; ++i) {
       ctx->Xi[i] ^= aad[i];
     }
   }

   ctx->ares = n;
   return 1;
 }

 int CRYPTO_gcm128_encrypt(const GCM128_KEY *key, GCM128_CONTEXT *ctx,
                           const uint8_t *in, uint8_t *out, size_t len) {
 #ifdef GCM_FUNCREF
   void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
   void (*gcm_ghash_p)(uint8_t Xi[16], const u128 Htable[16], const uint8_t *inp,
                       size_t len) = key->ghash;
 #endif

   uint64_t mlen = ctx->len.msg + len;
   if (mlen > ((UINT64_C(1) << 36) - 32) ||
       (sizeof(len) == 8 && mlen < len)) {
     return 0;
   }
   ctx->len.msg = mlen;

   if (ctx->ares) {
     // First call to encrypt finalizes GHASH(AAD)
     GCM_MUL(key, ctx, Xi);
     ctx->ares = 0;
   }

   unsigned n = ctx->mres;
   if (n) {
     while (n && len) {
       ctx->Xi[n] ^= *(out++) = *(in++) ^ ctx->EKi[n];
       --len;
       n = (n + 1) % 16;
     }
     if (n == 0) {
       GCM_MUL(key, ctx, Xi);
     } else {
       ctx->mres = n;
       return 1;
     }
   }

 #if defined(HW_GCM)
   // Check |len| to work around a C language bug. See https://crbug.com/1019588.
   if (key->impl != gcm_separate && len > 0) {
     // |hw_gcm_encrypt| may not process all the input given to it. It may
     // not process *any* of its input if it is deemed too small.
     size_t bulk = hw_gcm_encrypt(in, out, len, &key->aes, ctx->Yi, ctx->Xi,
                                  key->Htable, key->impl);
     in += bulk;
     out += bulk;
     len -= bulk;
   }
 #endif

   uint32_t ctr = CRYPTO_load_u32_be(ctx->Yi + 12);
   ctr128_f stream = key->ctr;
   while (len >= GHASH_CHUNK) {
     (*stream)(in, out, GHASH_CHUNK / 16, &key->aes, ctx->Yi);
     ctr += GHASH_CHUNK / 16;
     CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
     GHASH(key, ctx, out, GHASH_CHUNK);
     out += GHASH_CHUNK;
     in += GHASH_CHUNK;
     len -= GHASH_CHUNK;
   }

   size_t len_blocks = len & kSizeTWithoutLower4Bits;
   if (len_blocks != 0) {
     size_t j = len_blocks / 16;
     (*stream)(in, out, j, &key->aes, ctx->Yi);
     ctr += (uint32_t)j;
     CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
     in += len_blocks;
     len -= len_blocks;
     GHASH(key, ctx, out, len_blocks);
     out += len_blocks;
   }

   if (len) {
     key->block(ctx->Yi, ctx->EKi, &key->aes);
     ++ctr;
     CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
     while (len--) {
       ctx->Xi[n] ^= out[n] = in[n] ^ ctx->EKi[n];
       ++n;
     }
   }

   ctx->mres = n;
   return 1;
 }

 int CRYPTO_gcm128_decrypt(const GCM128_KEY *key, GCM128_CONTEXT *ctx,
                           const uint8_t *in, uint8_t *out, size_t len) {
 #ifdef GCM_FUNCREF
   void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
   void (*gcm_ghash_p)(uint8_t Xi[16], const u128 Htable[16], const uint8_t *inp,
                       size_t len) = key->ghash;
 #endif

   uint64_t mlen = ctx->len.msg + len;
   if (mlen > ((UINT64_C(1) << 36) - 32) ||
       (sizeof(len) == 8 && mlen < len)) {
     return 0;
   }
   ctx->len.msg = mlen;

   if (ctx->ares) {
     // First call to decrypt finalizes GHASH(AAD)
     GCM_MUL(key, ctx, Xi);
     ctx->ares = 0;
   }

   unsigned n = ctx->mres;
   if (n) {
     while (n && len) {
       uint8_t c = *(in++);
       *(out++) = c ^ ctx->EKi[n];
       ctx->Xi[n] ^= c;
       --len;
       n = (n + 1) % 16;
     }
     if (n == 0) {
       GCM_MUL(key, ctx, Xi);
     } else {
       ctx->mres = n;
       return 1;
     }
   }

 #if defined(HW_GCM)
   // Check |len| to work around a C language bug. See https://crbug.com/1019588.
   if (key->impl != gcm_separate && len > 0) {
     // |hw_gcm_decrypt| may not process all the input given to it. It may
     // not process *any* of its input if it is deemed too small.
     size_t bulk = hw_gcm_decrypt(in, out, len, &key->aes, ctx->Yi, ctx->Xi,
                                  key->Htable, key->impl);
     in += bulk;
     out += bulk;
     len -= bulk;
   }
 #endif

   uint32_t ctr = CRYPTO_load_u32_be(ctx->Yi + 12);
   ctr128_f stream = key->ctr;
   while (len >= GHASH_CHUNK) {
     GHASH(key, ctx, in, GHASH_CHUNK);
     (*stream)(in, out, GHASH_CHUNK / 16, &key->aes, ctx->Yi);
     ctr += GHASH_CHUNK / 16;
     CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
     out += GHASH_CHUNK;
     in += GHASH_CHUNK;
     len -= GHASH_CHUNK;
   }

   size_t len_blocks = len & kSizeTWithoutLower4Bits;
   if (len_blocks != 0) {
     size_t j = len_blocks / 16;
     GHASH(key, ctx, in, len_blocks);
     (*stream)(in, out, j, &key->aes, ctx->Yi);
     ctr += (uint32_t)j;
     CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
     out += len_blocks;
     in += len_blocks;
     len -= len_blocks;
   }

   if (len) {
     key->block(ctx->Yi, ctx->EKi, &key->aes);
     ++ctr;
     CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
     while (len--) {
       uint8_t c = in[n];
       ctx->Xi[n] ^= c;
       out[n] = c ^ ctx->EKi[n];
       ++n;
     }
   }

   ctx->mres = n;
   return 1;
 }

 int CRYPTO_gcm128_finish(const GCM128_KEY *key, GCM128_CONTEXT *ctx,
                          const uint8_t *tag, size_t len) {
 #ifdef GCM_FUNCREF
   void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
 #endif

   if (ctx->mres || ctx->ares) {
     GCM_MUL(key, ctx, Xi);
   }

   uint8_t len_block[16];
   CRYPTO_store_u64_be(len_block, ctx->len.aad << 3);
   CRYPTO_store_u64_be(len_block + 8, ctx->len.msg << 3);
   CRYPTO_xor16(ctx->Xi, ctx->Xi, len_block);
   GCM_MUL(key, ctx, Xi);
   CRYPTO_xor16(ctx->Xi, ctx->Xi, ctx->EK0);

   if (tag && len <= sizeof(ctx->Xi)) {
     return CRYPTO_memcmp(ctx->Xi, tag, len) == 0;
   } else {
     return 0;
   }
 }

 void CRYPTO_gcm128_tag(const GCM128_KEY *key, GCM128_CONTEXT *ctx, uint8_t *tag,
                        size_t len) {
   CRYPTO_gcm128_finish(key, ctx, NULL, 0);
   OPENSSL_memcpy(tag, ctx->Xi, len <= sizeof(ctx->Xi) ? len : sizeof(ctx->Xi));
 }

 #if defined(OPENSSL_X86) || defined(OPENSSL_X86_64)
 int crypto_gcm_clmul_enabled(void) {
 #if defined(GHASH_ASM_X86) || defined(GHASH_ASM_X86_64)
   return CRYPTO_is_FXSR_capable() && CRYPTO_is_PCLMUL_capable();
 #else
   return 0;
 #endif
 }
 #endif
	/*
	* Copyright 2010-2016 The OpenSSL Project Authors. All Rights Reserved.
	*
	* Licensed under the OpenSSL license (the "License"). You may not use
	* this file except in compliance with the License. You can obtain a copy
	* in the file LICENSE in the source distribution or at
	* https://www.openssl.org/source/license.html
	*/

	#include <openssl/base.h>

	#include <string.h>

	#include <openssl/mem.h>

	#include "../../internal.h"
	#include "../aes/internal.h"
	#include "internal.h"


	// kSizeTWithoutLower4Bits is a mask that can be used to zero the lower four
	// bits of a \|size_t\|.
	static const size_t kSizeTWithoutLower4Bits = (size_t) -16;


	#define GCM_MUL(key, ctx, Xi) gcm_gmult_nohw((ctx)->Xi, (key)->Htable)
	#define GHASH(key, ctx, in, len) \
	gcm_ghash_nohw((ctx)->Xi, (key)->Htable, in, len)
	// GHASH_CHUNK is "stride parameter" missioned to mitigate cache
	// trashing effect. In other words idea is to hash data while it's
	// still in L1 cache after encryption pass...
	#define GHASH_CHUNK (3 * 1024)

	#if defined(GHASH_ASM_X86_64) \|\| defined(GHASH_ASM_X86)
	static inline void gcm_reduce_1bit(u128 *V) {
	if (sizeof(crypto_word_t) == 8) {
	uint64_t T = UINT64_C(0xe100000000000000) & (0 - (V->hi & 1));
	V->hi = (V->lo << 63) \| (V->hi >> 1);
	V->lo = (V->lo >> 1) ^ T;
	} else {
	uint32_t T = 0xe1000000U & (0 - (uint32_t)(V->hi & 1));
	V->hi = (V->lo << 63) \| (V->hi >> 1);
	V->lo = (V->lo >> 1) ^ ((uint64_t)T << 32);
	}
	}

	void gcm_init_ssse3(u128 Htable[16], const uint64_t H[2]) {
	Htable[0].hi = 0;
	Htable[0].lo = 0;
	u128 V;
	V.hi = H[1];
	V.lo = H[0];

	Htable[8] = V;
	gcm_reduce_1bit(&V);
	Htable[4] = V;
	gcm_reduce_1bit(&V);
	Htable[2] = V;
	gcm_reduce_1bit(&V);
	Htable[1] = V;
	Htable[3].hi = V.hi ^ Htable[2].hi, Htable[3].lo = V.lo ^ Htable[2].lo;
	V = Htable[4];
	Htable[5].hi = V.hi ^ Htable[1].hi, Htable[5].lo = V.lo ^ Htable[1].lo;
	Htable[6].hi = V.hi ^ Htable[2].hi, Htable[6].lo = V.lo ^ Htable[2].lo;
	Htable[7].hi = V.hi ^ Htable[3].hi, Htable[7].lo = V.lo ^ Htable[3].lo;
	V = Htable[8];
	Htable[9].hi = V.hi ^ Htable[1].hi, Htable[9].lo = V.lo ^ Htable[1].lo;
	Htable[10].hi = V.hi ^ Htable[2].hi, Htable[10].lo = V.lo ^ Htable[2].lo;
	Htable[11].hi = V.hi ^ Htable[3].hi, Htable[11].lo = V.lo ^ Htable[3].lo;
	Htable[12].hi = V.hi ^ Htable[4].hi, Htable[12].lo = V.lo ^ Htable[4].lo;
	Htable[13].hi = V.hi ^ Htable[5].hi, Htable[13].lo = V.lo ^ Htable[5].lo;
	Htable[14].hi = V.hi ^ Htable[6].hi, Htable[14].lo = V.lo ^ Htable[6].lo;
	Htable[15].hi = V.hi ^ Htable[7].hi, Htable[15].lo = V.lo ^ Htable[7].lo;

	// Treat \|Htable\| as a 16x16 byte table and transpose it. Thus, Htable[i]
	// contains the i'th byte of j*H for all j.
	uint8_t Hbytes = (uint8_t )Htable;
	for (int i = 0; i < 16; i++) {
	for (int j = 0; j < i; j++) {
	uint8_t tmp = Hbytes[16*i + j];
	Hbytes[16i + j] = Hbytes[16j + i];
	Hbytes[16*j + i] = tmp;
	}
	}
	}
	#endif // GHASH_ASM_X86_64 \|\| GHASH_ASM_X86

	#ifdef GCM_FUNCREF
	#undef GCM_MUL
	#define GCM_MUL(key, ctx, Xi) (*gcm_gmult_p)((ctx)->Xi, (key)->Htable)
	#undef GHASH
	#define GHASH(key, ctx, in, len) \
	(*gcm_ghash_p)((ctx)->Xi, (key)->Htable, in, len)
	#endif // GCM_FUNCREF

	#if defined(HW_GCM) && defined(OPENSSL_X86_64)
	static size_t hw_gcm_encrypt(const uint8_t in, uint8_t out, size_t len,
	const AES_KEY *key, uint8_t ivec[16],
	uint8_t Xi[16], const u128 Htable[16],
	enum gcm_impl_t impl) {
	switch (impl) {
	case gcm_x86_vaes_avx10_256:
	len &= kSizeTWithoutLower4Bits;
	aes_gcm_enc_update_vaes_avx10_256(in, out, len, key, ivec, Htable, Xi);
	CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
	return len;
	case gcm_x86_vaes_avx10_512:
	len &= kSizeTWithoutLower4Bits;
	aes_gcm_enc_update_vaes_avx10_512(in, out, len, key, ivec, Htable, Xi);
	CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
	return len;
	default:
	return aesni_gcm_encrypt(in, out, len, key, ivec, Htable, Xi);
	}
	}

	static size_t hw_gcm_decrypt(const uint8_t in, uint8_t out, size_t len,
	const AES_KEY *key, uint8_t ivec[16],
	uint8_t Xi[16], const u128 Htable[16],
	enum gcm_impl_t impl) {
	switch (impl) {
	case gcm_x86_vaes_avx10_256:
	len &= kSizeTWithoutLower4Bits;
	aes_gcm_dec_update_vaes_avx10_256(in, out, len, key, ivec, Htable, Xi);
	CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
	return len;
	case gcm_x86_vaes_avx10_512:
	len &= kSizeTWithoutLower4Bits;
	aes_gcm_dec_update_vaes_avx10_512(in, out, len, key, ivec, Htable, Xi);
	CRYPTO_store_u32_be(&ivec[12], CRYPTO_load_u32_be(&ivec[12]) + len / 16);
	return len;
	default:
	return aesni_gcm_decrypt(in, out, len, key, ivec, Htable, Xi);
	}
	}
	#endif // HW_GCM && X86_64

	#if defined(HW_GCM) && defined(OPENSSL_AARCH64)

	static size_t hw_gcm_encrypt(const uint8_t in, uint8_t out, size_t len,
	const AES_KEY *key, uint8_t ivec[16],
	uint8_t Xi[16], const u128 Htable[16],
	enum gcm_impl_t impl) {
	const size_t len_blocks = len & kSizeTWithoutLower4Bits;
	if (!len_blocks) {
	return 0;
	}
	aes_gcm_enc_kernel(in, len_blocks * 8, out, Xi, ivec, key, Htable);
	return len_blocks;
	}

	static size_t hw_gcm_decrypt(const uint8_t in, uint8_t out, size_t len,
	const AES_KEY *key, uint8_t ivec[16],
	uint8_t Xi[16], const u128 Htable[16],
	enum gcm_impl_t impl) {
	const size_t len_blocks = len & kSizeTWithoutLower4Bits;
	if (!len_blocks) {
	return 0;
	}
	aes_gcm_dec_kernel(in, len_blocks * 8, out, Xi, ivec, key, Htable);
	return len_blocks;
	}

	#endif // HW_GCM && AARCH64

	void CRYPTO_ghash_init(gmult_func out_mult, ghash_func out_hash,
	u128 out_table[16], const uint8_t gcm_key[16]) {
	// H is passed to \|gcm_init_*\| as a pair of byte-swapped, 64-bit values.
	uint64_t H[2] = {CRYPTO_load_u64_be(gcm_key),
	CRYPTO_load_u64_be(gcm_key + 8)};

	#if defined(GHASH_ASM_X86_64)
	if (crypto_gcm_clmul_enabled()) {
	if (CRYPTO_is_AVX512BW_capable() && CRYPTO_is_AVX512VL_capable() &&
	CRYPTO_is_VPCLMULQDQ_capable() && CRYPTO_is_BMI2_capable()) {
	gcm_init_vpclmulqdq_avx10(out_table, H);
	*out_mult = gcm_gmult_vpclmulqdq_avx10;
	if (CRYPTO_cpu_avoid_zmm_registers()) {
	*out_hash = gcm_ghash_vpclmulqdq_avx10_256;
	} else {
	*out_hash = gcm_ghash_vpclmulqdq_avx10_512;
	}
	return;
	}
	if (CRYPTO_is_AVX_capable() && CRYPTO_is_MOVBE_capable()) {
	gcm_init_avx(out_table, H);
	*out_mult = gcm_gmult_avx;
	*out_hash = gcm_ghash_avx;
	return;
	}
	gcm_init_clmul(out_table, H);
	*out_mult = gcm_gmult_clmul;
	*out_hash = gcm_ghash_clmul;
	return;
	}
	if (CRYPTO_is_SSSE3_capable()) {
	gcm_init_ssse3(out_table, H);
	*out_mult = gcm_gmult_ssse3;
	*out_hash = gcm_ghash_ssse3;
	return;
	}
	#elif defined(GHASH_ASM_X86)
	if (crypto_gcm_clmul_enabled()) {
	gcm_init_clmul(out_table, H);
	*out_mult = gcm_gmult_clmul;
	*out_hash = gcm_ghash_clmul;
	return;
	}
	if (CRYPTO_is_SSSE3_capable()) {
	gcm_init_ssse3(out_table, H);
	*out_mult = gcm_gmult_ssse3;
	*out_hash = gcm_ghash_ssse3;
	return;
	}
	#elif defined(GHASH_ASM_ARM)
	if (gcm_pmull_capable()) {
	gcm_init_v8(out_table, H);
	*out_mult = gcm_gmult_v8;
	*out_hash = gcm_ghash_v8;
	return;
	}

	if (gcm_neon_capable()) {
	gcm_init_neon(out_table, H);
	*out_mult = gcm_gmult_neon;
	*out_hash = gcm_ghash_neon;
	return;
	}
	#endif

	gcm_init_nohw(out_table, H);
	*out_mult = gcm_gmult_nohw;
	*out_hash = gcm_ghash_nohw;
	}

	void CRYPTO_gcm128_init_aes_key(GCM128_KEY gcm_key, const uint8_t key,
	size_t key_bytes) {
	switch (key_bytes) {
	case 16:
	boringssl_fips_inc_counter(fips_counter_evp_aes_128_gcm);
	break;

	case 32:
	boringssl_fips_inc_counter(fips_counter_evp_aes_256_gcm);
	break;
	}

	OPENSSL_memset(gcm_key, 0, sizeof(*gcm_key));
	int is_hwaes;
	gcm_key->ctr = aes_ctr_set_key(&gcm_key->aes, &is_hwaes, &gcm_key->block, key,
	key_bytes);

	uint8_t ghash_key[16];
	OPENSSL_memset(ghash_key, 0, sizeof(ghash_key));
	gcm_key->block(ghash_key, ghash_key, &gcm_key->aes);

	CRYPTO_ghash_init(&gcm_key->gmult, &gcm_key->ghash, gcm_key->Htable,
	ghash_key);

	#if !defined(OPENSSL_NO_ASM)
	#if defined(OPENSSL_X86_64)
	if (gcm_key->ghash == gcm_ghash_vpclmulqdq_avx10_256 &&
	CRYPTO_is_VAES_capable()) {
	gcm_key->impl = gcm_x86_vaes_avx10_256;
	} else if (gcm_key->ghash == gcm_ghash_vpclmulqdq_avx10_512 &&
	CRYPTO_is_VAES_capable()) {
	gcm_key->impl = gcm_x86_vaes_avx10_512;
	} else if (gcm_key->ghash == gcm_ghash_avx && is_hwaes) {
	gcm_key->impl = gcm_x86_aesni;
	}
	#elif defined(OPENSSL_AARCH64)
	if (gcm_pmull_capable() && is_hwaes) {
	gcm_key->impl = gcm_arm64_aes;
	}
	#endif
	#endif
	}

	void CRYPTO_gcm128_init_ctx(const GCM128_KEY key, GCM128_CONTEXT ctx,
	const uint8_t *iv, size_t iv_len) {
	#ifdef GCM_FUNCREF
	void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
	#endif

	OPENSSL_memset(&ctx->Yi, 0, sizeof(ctx->Yi));
	OPENSSL_memset(&ctx->Xi, 0, sizeof(ctx->Xi));
	ctx->len.aad = 0;
	ctx->len.msg = 0;
	ctx->ares = 0;
	ctx->mres = 0;

	uint32_t ctr;
	if (iv_len == 12) {
	OPENSSL_memcpy(ctx->Yi, iv, 12);
	ctx->Yi[15] = 1;
	ctr = 1;
	} else {
	uint64_t len0 = iv_len;

	while (iv_len >= 16) {
	CRYPTO_xor16(ctx->Yi, ctx->Yi, iv);
	GCM_MUL(key, ctx, Yi);
	iv += 16;
	iv_len -= 16;
	}
	if (iv_len) {
	for (size_t i = 0; i < iv_len; ++i) {
	ctx->Yi[i] ^= iv[i];
	}
	GCM_MUL(key, ctx, Yi);
	}

	uint8_t len_block[16];
	OPENSSL_memset(len_block, 0, 8);
	CRYPTO_store_u64_be(len_block + 8, len0 << 3);
	CRYPTO_xor16(ctx->Yi, ctx->Yi, len_block);

	GCM_MUL(key, ctx, Yi);
	ctr = CRYPTO_load_u32_be(ctx->Yi + 12);
	}

	key->block(ctx->Yi, ctx->EK0, &key->aes);
	++ctr;
	CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
	}

	int CRYPTO_gcm128_aad(const GCM128_KEY key, GCM128_CONTEXT ctx,
	const uint8_t *aad, size_t aad_len) {
	#ifdef GCM_FUNCREF
	void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
	void (gcm_ghash_p)(uint8_t Xi[16], const u128 Htable[16], const uint8_t inp,
	size_t len) = key->ghash;
	#endif

	if (ctx->len.msg != 0) {
	// The caller must have finished the AAD before providing other input.
	return 0;
	}

	uint64_t alen = ctx->len.aad + aad_len;
	if (alen > (UINT64_C(1) << 61) \|\| (sizeof(aad_len) == 8 && alen < aad_len)) {
	return 0;
	}
	ctx->len.aad = alen;

	unsigned n = ctx->ares;
	if (n) {
	while (n && aad_len) {
	ctx->Xi[n] ^= *(aad++);
	--aad_len;
	n = (n + 1) % 16;
	}
	if (n == 0) {
	GCM_MUL(key, ctx, Xi);
	} else {
	ctx->ares = n;
	return 1;
	}
	}

	// Process a whole number of blocks.
	size_t len_blocks = aad_len & kSizeTWithoutLower4Bits;
	if (len_blocks != 0) {
	GHASH(key, ctx, aad, len_blocks);
	aad += len_blocks;
	aad_len -= len_blocks;
	}

	// Process the remainder.
	if (aad_len != 0) {
	n = (unsigned int)aad_len;
	for (size_t i = 0; i < aad_len; ++i) {
	ctx->Xi[i] ^= aad[i];
	}
	}

	ctx->ares = n;
	return 1;
	}

	int CRYPTO_gcm128_encrypt(const GCM128_KEY key, GCM128_CONTEXT ctx,
	const uint8_t in, uint8_t out, size_t len) {
	#ifdef GCM_FUNCREF
	void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
	void (gcm_ghash_p)(uint8_t Xi[16], const u128 Htable[16], const uint8_t inp,
	size_t len) = key->ghash;
	#endif

	uint64_t mlen = ctx->len.msg + len;
	if (mlen > ((UINT64_C(1) << 36) - 32) \|\|
	(sizeof(len) == 8 && mlen < len)) {
	return 0;
	}
	ctx->len.msg = mlen;

	if (ctx->ares) {
	// First call to encrypt finalizes GHASH(AAD)
	GCM_MUL(key, ctx, Xi);
	ctx->ares = 0;
	}

	unsigned n = ctx->mres;
	if (n) {
	while (n && len) {
	ctx->Xi[n] ^= (out++) = (in++) ^ ctx->EKi[n];
	--len;
	n = (n + 1) % 16;
	}
	if (n == 0) {
	GCM_MUL(key, ctx, Xi);
	} else {
	ctx->mres = n;
	return 1;
	}
	}

	#if defined(HW_GCM)
	// Check \|len\| to work around a C language bug. See https://crbug.com/1019588.
	if (key->impl != gcm_separate && len > 0) {
	// \|hw_gcm_encrypt\| may not process all the input given to it. It may
	// not process any of its input if it is deemed too small.
	size_t bulk = hw_gcm_encrypt(in, out, len, &key->aes, ctx->Yi, ctx->Xi,
	key->Htable, key->impl);
	in += bulk;
	out += bulk;
	len -= bulk;
	}
	#endif

	uint32_t ctr = CRYPTO_load_u32_be(ctx->Yi + 12);
	ctr128_f stream = key->ctr;
	while (len >= GHASH_CHUNK) {
	(*stream)(in, out, GHASH_CHUNK / 16, &key->aes, ctx->Yi);
	ctr += GHASH_CHUNK / 16;
	CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
	GHASH(key, ctx, out, GHASH_CHUNK);
	out += GHASH_CHUNK;
	in += GHASH_CHUNK;
	len -= GHASH_CHUNK;
	}

	size_t len_blocks = len & kSizeTWithoutLower4Bits;
	if (len_blocks != 0) {
	size_t j = len_blocks / 16;
	(*stream)(in, out, j, &key->aes, ctx->Yi);
	ctr += (uint32_t)j;
	CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
	in += len_blocks;
	len -= len_blocks;
	GHASH(key, ctx, out, len_blocks);
	out += len_blocks;
	}

	if (len) {
	key->block(ctx->Yi, ctx->EKi, &key->aes);
	++ctr;
	CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
	while (len--) {
	ctx->Xi[n] ^= out[n] = in[n] ^ ctx->EKi[n];
	++n;
	}
	}

	ctx->mres = n;
	return 1;
	}

	int CRYPTO_gcm128_decrypt(const GCM128_KEY key, GCM128_CONTEXT ctx,
	const uint8_t in, uint8_t out, size_t len) {
	#ifdef GCM_FUNCREF
	void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
	void (gcm_ghash_p)(uint8_t Xi[16], const u128 Htable[16], const uint8_t inp,
	size_t len) = key->ghash;
	#endif

	uint64_t mlen = ctx->len.msg + len;
	if (mlen > ((UINT64_C(1) << 36) - 32) \|\|
	(sizeof(len) == 8 && mlen < len)) {
	return 0;
	}
	ctx->len.msg = mlen;

	if (ctx->ares) {
	// First call to decrypt finalizes GHASH(AAD)
	GCM_MUL(key, ctx, Xi);
	ctx->ares = 0;
	}

	unsigned n = ctx->mres;
	if (n) {
	while (n && len) {
	uint8_t c = *(in++);
	*(out++) = c ^ ctx->EKi[n];
	ctx->Xi[n] ^= c;
	--len;
	n = (n + 1) % 16;
	}
	if (n == 0) {
	GCM_MUL(key, ctx, Xi);
	} else {
	ctx->mres = n;
	return 1;
	}
	}

	#if defined(HW_GCM)
	// Check \|len\| to work around a C language bug. See https://crbug.com/1019588.
	if (key->impl != gcm_separate && len > 0) {
	// \|hw_gcm_decrypt\| may not process all the input given to it. It may
	// not process any of its input if it is deemed too small.
	size_t bulk = hw_gcm_decrypt(in, out, len, &key->aes, ctx->Yi, ctx->Xi,
	key->Htable, key->impl);
	in += bulk;
	out += bulk;
	len -= bulk;
	}
	#endif

	uint32_t ctr = CRYPTO_load_u32_be(ctx->Yi + 12);
	ctr128_f stream = key->ctr;
	while (len >= GHASH_CHUNK) {
	GHASH(key, ctx, in, GHASH_CHUNK);
	(*stream)(in, out, GHASH_CHUNK / 16, &key->aes, ctx->Yi);
	ctr += GHASH_CHUNK / 16;
	CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
	out += GHASH_CHUNK;
	in += GHASH_CHUNK;
	len -= GHASH_CHUNK;
	}

	size_t len_blocks = len & kSizeTWithoutLower4Bits;
	if (len_blocks != 0) {
	size_t j = len_blocks / 16;
	GHASH(key, ctx, in, len_blocks);
	(*stream)(in, out, j, &key->aes, ctx->Yi);
	ctr += (uint32_t)j;
	CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
	out += len_blocks;
	in += len_blocks;
	len -= len_blocks;
	}

	if (len) {
	key->block(ctx->Yi, ctx->EKi, &key->aes);
	++ctr;
	CRYPTO_store_u32_be(ctx->Yi + 12, ctr);
	while (len--) {
	uint8_t c = in[n];
	ctx->Xi[n] ^= c;
	out[n] = c ^ ctx->EKi[n];
	++n;
	}
	}

	ctx->mres = n;
	return 1;
	}

	int CRYPTO_gcm128_finish(const GCM128_KEY key, GCM128_CONTEXT ctx,
	const uint8_t *tag, size_t len) {
	#ifdef GCM_FUNCREF
	void (*gcm_gmult_p)(uint8_t Xi[16], const u128 Htable[16]) = key->gmult;
	#endif

	if (ctx->mres \|\| ctx->ares) {
	GCM_MUL(key, ctx, Xi);
	}

	uint8_t len_block[16];
	CRYPTO_store_u64_be(len_block, ctx->len.aad << 3);
	CRYPTO_store_u64_be(len_block + 8, ctx->len.msg << 3);
	CRYPTO_xor16(ctx->Xi, ctx->Xi, len_block);
	GCM_MUL(key, ctx, Xi);
	CRYPTO_xor16(ctx->Xi, ctx->Xi, ctx->EK0);

	if (tag && len <= sizeof(ctx->Xi)) {
	return CRYPTO_memcmp(ctx->Xi, tag, len) == 0;
	} else {
	return 0;
	}
	}

	void CRYPTO_gcm128_tag(const GCM128_KEY key, GCM128_CONTEXT ctx, uint8_t *tag,
	size_t len) {
	CRYPTO_gcm128_finish(key, ctx, NULL, 0);
	OPENSSL_memcpy(tag, ctx->Xi, len <= sizeof(ctx->Xi) ? len : sizeof(ctx->Xi));
	}

	#if defined(OPENSSL_X86) \|\| defined(OPENSSL_X86_64)
	int crypto_gcm_clmul_enabled(void) {
	#if defined(GHASH_ASM_X86) \|\| defined(GHASH_ASM_X86_64)
	return CRYPTO_is_FXSR_capable() && CRYPTO_is_PCLMUL_capable();
	#else
	return 0;
	#endif
	}
	#endif