ref: 2cdc6577ef8a251bf1740439cf5bfc47050dab41
dir: /third_party/boringssl/src/crypto/fipsmodule/modes/gcm.c/
/* ====================================================================
* Copyright (c) 2008 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ==================================================================== */
#include <openssl/base.h>
#include <assert.h>
#include <string.h>
#include <openssl/mem.h>
#include <openssl/cpu.h>
#include "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(ctx, Xi) gcm_gmult_nohw((ctx)->Xi.u, (ctx)->gcm_key.Htable)
#define GHASH(ctx, in, len) \
gcm_ghash_nohw((ctx)->Xi.u, (ctx)->gcm_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(ctx, Xi) (*gcm_gmult_p)((ctx)->Xi.u, (ctx)->gcm_key.Htable)
#undef GHASH
#define GHASH(ctx, in, len) \
(*gcm_ghash_p)((ctx)->Xi.u, (ctx)->gcm_key.Htable, in, len)
#endif // GCM_FUNCREF
void CRYPTO_ghash_init(gmult_func *out_mult, ghash_func *out_hash,
u128 *out_key, u128 out_table[16], int *out_is_avx,
const uint8_t gcm_key[16]) {
*out_is_avx = 0;
union {
uint64_t u[2];
uint8_t c[16];
} H;
OPENSSL_memcpy(H.c, gcm_key, 16);
// H is stored in host byte order
H.u[0] = CRYPTO_bswap8(H.u[0]);
H.u[1] = CRYPTO_bswap8(H.u[1]);
OPENSSL_memcpy(out_key, H.c, 16);
#if defined(GHASH_ASM_X86_64)
if (crypto_gcm_clmul_enabled()) {
if (((OPENSSL_ia32cap_get()[1] >> 22) & 0x41) == 0x41) { // AVX+MOVBE
gcm_init_avx(out_table, H.u);
*out_mult = gcm_gmult_avx;
*out_hash = gcm_ghash_avx;
*out_is_avx = 1;
return;
}
gcm_init_clmul(out_table, H.u);
*out_mult = gcm_gmult_clmul;
*out_hash = gcm_ghash_clmul;
return;
}
if (gcm_ssse3_capable()) {
gcm_init_ssse3(out_table, H.u);
*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.u);
*out_mult = gcm_gmult_clmul;
*out_hash = gcm_ghash_clmul;
return;
}
if (gcm_ssse3_capable()) {
gcm_init_ssse3(out_table, H.u);
*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.u);
*out_mult = gcm_gmult_v8;
*out_hash = gcm_ghash_v8;
return;
}
if (gcm_neon_capable()) {
gcm_init_neon(out_table, H.u);
*out_mult = gcm_gmult_neon;
*out_hash = gcm_ghash_neon;
return;
}
#elif defined(GHASH_ASM_PPC64LE)
if (CRYPTO_is_PPC64LE_vcrypto_capable()) {
gcm_init_p8(out_table, H.u);
*out_mult = gcm_gmult_p8;
*out_hash = gcm_ghash_p8;
return;
}
#endif
gcm_init_nohw(out_table, H.u);
*out_mult = gcm_gmult_nohw;
*out_hash = gcm_ghash_nohw;
}
void CRYPTO_gcm128_init_key(GCM128_KEY *gcm_key, const AES_KEY *aes_key,
block128_f block, int block_is_hwaes) {
OPENSSL_memset(gcm_key, 0, sizeof(*gcm_key));
gcm_key->block = block;
uint8_t ghash_key[16];
OPENSSL_memset(ghash_key, 0, sizeof(ghash_key));
(*block)(ghash_key, ghash_key, aes_key);
int is_avx;
CRYPTO_ghash_init(&gcm_key->gmult, &gcm_key->ghash, &gcm_key->H,
gcm_key->Htable, &is_avx, ghash_key);
gcm_key->use_aesni_gcm_crypt = (is_avx && block_is_hwaes) ? 1 : 0;
}
void CRYPTO_gcm128_setiv(GCM128_CONTEXT *ctx, const AES_KEY *key,
const uint8_t *iv, size_t len) {
#ifdef GCM_FUNCREF
void (*gcm_gmult_p)(uint64_t Xi[2], const u128 Htable[16]) =
ctx->gcm_key.gmult;
#endif
ctx->Yi.u[0] = 0;
ctx->Yi.u[1] = 0;
ctx->Xi.u[0] = 0;
ctx->Xi.u[1] = 0;
ctx->len.u[0] = 0; // AAD length
ctx->len.u[1] = 0; // message length
ctx->ares = 0;
ctx->mres = 0;
uint32_t ctr;
if (len == 12) {
OPENSSL_memcpy(ctx->Yi.c, iv, 12);
ctx->Yi.c[15] = 1;
ctr = 1;
} else {
uint64_t len0 = len;
while (len >= 16) {
for (size_t i = 0; i < 16; ++i) {
ctx->Yi.c[i] ^= iv[i];
}
GCM_MUL(ctx, Yi);
iv += 16;
len -= 16;
}
if (len) {
for (size_t i = 0; i < len; ++i) {
ctx->Yi.c[i] ^= iv[i];
}
GCM_MUL(ctx, Yi);
}
len0 <<= 3;
ctx->Yi.u[1] ^= CRYPTO_bswap8(len0);
GCM_MUL(ctx, Yi);
ctr = CRYPTO_bswap4(ctx->Yi.d[3]);
}
(*ctx->gcm_key.block)(ctx->Yi.c, ctx->EK0.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
}
int CRYPTO_gcm128_aad(GCM128_CONTEXT *ctx, const uint8_t *aad, size_t len) {
#ifdef GCM_FUNCREF
void (*gcm_gmult_p)(uint64_t Xi[2], const u128 Htable[16]) =
ctx->gcm_key.gmult;
void (*gcm_ghash_p)(uint64_t Xi[2], const u128 Htable[16], const uint8_t *inp,
size_t len) = ctx->gcm_key.ghash;
#endif
if (ctx->len.u[1]) {
return 0;
}
uint64_t alen = ctx->len.u[0] + len;
if (alen > (UINT64_C(1) << 61) || (sizeof(len) == 8 && alen < len)) {
return 0;
}
ctx->len.u[0] = alen;
unsigned n = ctx->ares;
if (n) {
while (n && len) {
ctx->Xi.c[n] ^= *(aad++);
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx, Xi);
} else {
ctx->ares = n;
return 1;
}
}
// Process a whole number of blocks.
size_t len_blocks = len & kSizeTWithoutLower4Bits;
if (len_blocks != 0) {
GHASH(ctx, aad, len_blocks);
aad += len_blocks;
len -= len_blocks;
}
// Process the remainder.
if (len != 0) {
n = (unsigned int)len;
for (size_t i = 0; i < len; ++i) {
ctx->Xi.c[i] ^= aad[i];
}
}
ctx->ares = n;
return 1;
}
int CRYPTO_gcm128_encrypt(GCM128_CONTEXT *ctx, const AES_KEY *key,
const uint8_t *in, uint8_t *out, size_t len) {
block128_f block = ctx->gcm_key.block;
#ifdef GCM_FUNCREF
void (*gcm_gmult_p)(uint64_t Xi[2], const u128 Htable[16]) =
ctx->gcm_key.gmult;
void (*gcm_ghash_p)(uint64_t Xi[2], const u128 Htable[16], const uint8_t *inp,
size_t len) = ctx->gcm_key.ghash;
#endif
uint64_t mlen = ctx->len.u[1] + len;
if (mlen > ((UINT64_C(1) << 36) - 32) ||
(sizeof(len) == 8 && mlen < len)) {
return 0;
}
ctx->len.u[1] = mlen;
if (ctx->ares) {
// First call to encrypt finalizes GHASH(AAD)
GCM_MUL(ctx, Xi);
ctx->ares = 0;
}
unsigned n = ctx->mres;
if (n) {
while (n && len) {
ctx->Xi.c[n] ^= *(out++) = *(in++) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx, Xi);
} else {
ctx->mres = n;
return 1;
}
}
uint32_t ctr = CRYPTO_bswap4(ctx->Yi.d[3]);
while (len >= GHASH_CHUNK) {
size_t j = GHASH_CHUNK;
while (j) {
(*block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
for (size_t i = 0; i < 16; i += sizeof(crypto_word_t)) {
CRYPTO_store_word_le(out + i,
CRYPTO_load_word_le(in + i) ^
ctx->EKi.t[i / sizeof(crypto_word_t)]);
}
out += 16;
in += 16;
j -= 16;
}
GHASH(ctx, out - GHASH_CHUNK, GHASH_CHUNK);
len -= GHASH_CHUNK;
}
size_t len_blocks = len & kSizeTWithoutLower4Bits;
if (len_blocks != 0) {
while (len >= 16) {
(*block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
for (size_t i = 0; i < 16; i += sizeof(crypto_word_t)) {
CRYPTO_store_word_le(out + i,
CRYPTO_load_word_le(in + i) ^
ctx->EKi.t[i / sizeof(crypto_word_t)]);
}
out += 16;
in += 16;
len -= 16;
}
GHASH(ctx, out - len_blocks, len_blocks);
}
if (len) {
(*block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
while (len--) {
ctx->Xi.c[n] ^= out[n] = in[n] ^ ctx->EKi.c[n];
++n;
}
}
ctx->mres = n;
return 1;
}
int CRYPTO_gcm128_decrypt(GCM128_CONTEXT *ctx, const AES_KEY *key,
const unsigned char *in, unsigned char *out,
size_t len) {
block128_f block = ctx->gcm_key.block;
#ifdef GCM_FUNCREF
void (*gcm_gmult_p)(uint64_t Xi[2], const u128 Htable[16]) =
ctx->gcm_key.gmult;
void (*gcm_ghash_p)(uint64_t Xi[2], const u128 Htable[16], const uint8_t *inp,
size_t len) = ctx->gcm_key.ghash;
#endif
uint64_t mlen = ctx->len.u[1] + len;
if (mlen > ((UINT64_C(1) << 36) - 32) ||
(sizeof(len) == 8 && mlen < len)) {
return 0;
}
ctx->len.u[1] = mlen;
if (ctx->ares) {
// First call to decrypt finalizes GHASH(AAD)
GCM_MUL(ctx, Xi);
ctx->ares = 0;
}
unsigned n = ctx->mres;
if (n) {
while (n && len) {
uint8_t c = *(in++);
*(out++) = c ^ ctx->EKi.c[n];
ctx->Xi.c[n] ^= c;
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx, Xi);
} else {
ctx->mres = n;
return 1;
}
}
uint32_t ctr = CRYPTO_bswap4(ctx->Yi.d[3]);
while (len >= GHASH_CHUNK) {
size_t j = GHASH_CHUNK;
GHASH(ctx, in, GHASH_CHUNK);
while (j) {
(*block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
for (size_t i = 0; i < 16; i += sizeof(crypto_word_t)) {
CRYPTO_store_word_le(out + i,
CRYPTO_load_word_le(in + i) ^
ctx->EKi.t[i / sizeof(crypto_word_t)]);
}
out += 16;
in += 16;
j -= 16;
}
len -= GHASH_CHUNK;
}
size_t len_blocks = len & kSizeTWithoutLower4Bits;
if (len_blocks != 0) {
GHASH(ctx, in, len_blocks);
while (len >= 16) {
(*block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
for (size_t i = 0; i < 16; i += sizeof(crypto_word_t)) {
CRYPTO_store_word_le(out + i,
CRYPTO_load_word_le(in + i) ^
ctx->EKi.t[i / sizeof(crypto_word_t)]);
}
out += 16;
in += 16;
len -= 16;
}
}
if (len) {
(*block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
while (len--) {
uint8_t c = in[n];
ctx->Xi.c[n] ^= c;
out[n] = c ^ ctx->EKi.c[n];
++n;
}
}
ctx->mres = n;
return 1;
}
int CRYPTO_gcm128_encrypt_ctr32(GCM128_CONTEXT *ctx, const AES_KEY *key,
const uint8_t *in, uint8_t *out, size_t len,
ctr128_f stream) {
#ifdef GCM_FUNCREF
void (*gcm_gmult_p)(uint64_t Xi[2], const u128 Htable[16]) =
ctx->gcm_key.gmult;
void (*gcm_ghash_p)(uint64_t Xi[2], const u128 Htable[16], const uint8_t *inp,
size_t len) = ctx->gcm_key.ghash;
#endif
uint64_t mlen = ctx->len.u[1] + len;
if (mlen > ((UINT64_C(1) << 36) - 32) ||
(sizeof(len) == 8 && mlen < len)) {
return 0;
}
ctx->len.u[1] = mlen;
if (ctx->ares) {
// First call to encrypt finalizes GHASH(AAD)
GCM_MUL(ctx, Xi);
ctx->ares = 0;
}
unsigned n = ctx->mres;
if (n) {
while (n && len) {
ctx->Xi.c[n] ^= *(out++) = *(in++) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx, Xi);
} else {
ctx->mres = n;
return 1;
}
}
#if defined(AESNI_GCM)
// Check |len| to work around a C language bug. See https://crbug.com/1019588.
if (ctx->gcm_key.use_aesni_gcm_crypt && len > 0) {
// |aesni_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 = aesni_gcm_encrypt(in, out, len, key, ctx->Yi.c, ctx->Xi.u);
in += bulk;
out += bulk;
len -= bulk;
}
#endif
uint32_t ctr = CRYPTO_bswap4(ctx->Yi.d[3]);
while (len >= GHASH_CHUNK) {
(*stream)(in, out, GHASH_CHUNK / 16, key, ctx->Yi.c);
ctr += GHASH_CHUNK / 16;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
GHASH(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, ctx->Yi.c);
ctr += (unsigned int)j;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
in += len_blocks;
len -= len_blocks;
GHASH(ctx, out, len_blocks);
out += len_blocks;
}
if (len) {
(*ctx->gcm_key.block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
while (len--) {
ctx->Xi.c[n] ^= out[n] = in[n] ^ ctx->EKi.c[n];
++n;
}
}
ctx->mres = n;
return 1;
}
int CRYPTO_gcm128_decrypt_ctr32(GCM128_CONTEXT *ctx, const AES_KEY *key,
const uint8_t *in, uint8_t *out, size_t len,
ctr128_f stream) {
#ifdef GCM_FUNCREF
void (*gcm_gmult_p)(uint64_t Xi[2], const u128 Htable[16]) =
ctx->gcm_key.gmult;
void (*gcm_ghash_p)(uint64_t Xi[2], const u128 Htable[16], const uint8_t *inp,
size_t len) = ctx->gcm_key.ghash;
#endif
uint64_t mlen = ctx->len.u[1] + len;
if (mlen > ((UINT64_C(1) << 36) - 32) ||
(sizeof(len) == 8 && mlen < len)) {
return 0;
}
ctx->len.u[1] = mlen;
if (ctx->ares) {
// First call to decrypt finalizes GHASH(AAD)
GCM_MUL(ctx, Xi);
ctx->ares = 0;
}
unsigned n = ctx->mres;
if (n) {
while (n && len) {
uint8_t c = *(in++);
*(out++) = c ^ ctx->EKi.c[n];
ctx->Xi.c[n] ^= c;
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx, Xi);
} else {
ctx->mres = n;
return 1;
}
}
#if defined(AESNI_GCM)
// Check |len| to work around a C language bug. See https://crbug.com/1019588.
if (ctx->gcm_key.use_aesni_gcm_crypt && len > 0) {
// |aesni_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 = aesni_gcm_decrypt(in, out, len, key, ctx->Yi.c, ctx->Xi.u);
in += bulk;
out += bulk;
len -= bulk;
}
#endif
uint32_t ctr = CRYPTO_bswap4(ctx->Yi.d[3]);
while (len >= GHASH_CHUNK) {
GHASH(ctx, in, GHASH_CHUNK);
(*stream)(in, out, GHASH_CHUNK / 16, key, ctx->Yi.c);
ctr += GHASH_CHUNK / 16;
ctx->Yi.d[3] = CRYPTO_bswap4(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(ctx, in, len_blocks);
(*stream)(in, out, j, key, ctx->Yi.c);
ctr += (unsigned int)j;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
out += len_blocks;
in += len_blocks;
len -= len_blocks;
}
if (len) {
(*ctx->gcm_key.block)(ctx->Yi.c, ctx->EKi.c, key);
++ctr;
ctx->Yi.d[3] = CRYPTO_bswap4(ctr);
while (len--) {
uint8_t c = in[n];
ctx->Xi.c[n] ^= c;
out[n] = c ^ ctx->EKi.c[n];
++n;
}
}
ctx->mres = n;
return 1;
}
int CRYPTO_gcm128_finish(GCM128_CONTEXT *ctx, const uint8_t *tag, size_t len) {
#ifdef GCM_FUNCREF
void (*gcm_gmult_p)(uint64_t Xi[2], const u128 Htable[16]) =
ctx->gcm_key.gmult;
#endif
if (ctx->mres || ctx->ares) {
GCM_MUL(ctx, Xi);
}
ctx->Xi.u[0] ^= CRYPTO_bswap8(ctx->len.u[0] << 3);
ctx->Xi.u[1] ^= CRYPTO_bswap8(ctx->len.u[1] << 3);
GCM_MUL(ctx, Xi);
ctx->Xi.u[0] ^= ctx->EK0.u[0];
ctx->Xi.u[1] ^= ctx->EK0.u[1];
if (tag && len <= sizeof(ctx->Xi)) {
return CRYPTO_memcmp(ctx->Xi.c, tag, len) == 0;
} else {
return 0;
}
}
void CRYPTO_gcm128_tag(GCM128_CONTEXT *ctx, unsigned char *tag, size_t len) {
CRYPTO_gcm128_finish(ctx, NULL, 0);
OPENSSL_memcpy(tag, ctx->Xi.c,
len <= sizeof(ctx->Xi.c) ? len : sizeof(ctx->Xi.c));
}
#if defined(OPENSSL_X86) || defined(OPENSSL_X86_64)
int crypto_gcm_clmul_enabled(void) {
#if defined(GHASH_ASM_X86) || defined(GHASH_ASM_X86_64)
const uint32_t *ia32cap = OPENSSL_ia32cap_get();
return (ia32cap[0] & (1 << 24)) && // check FXSR bit
(ia32cap[1] & (1 << 1)); // check PCLMULQDQ bit
#else
return 0;
#endif
}
#endif