gcm128.c
/*
* Copyright 2010-2023 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (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 <string.h>
#include <openssl/crypto.h>
#include "internal/cryptlib.h"
#include "internal/endian.h"
#include "crypto/modes.h"
#if defined(__GNUC__) && !defined(STRICT_ALIGNMENT)
typedef size_t size_t_aX __attribute((__aligned__(1)));
#else
typedef size_t size_t_aX;
#endif
#if defined(BSWAP4) && defined(STRICT_ALIGNMENT)
/* redefine, because alignment is ensured */
# undef GETU32
# define GETU32(p) BSWAP4(*(const u32 *)(p))
# undef PUTU32
# define PUTU32(p,v) *(u32 *)(p) = BSWAP4(v)
#endif
/* RISC-V uses C implementation as a fallback. */
#if defined(__riscv)
# define INCLUDE_C_GMULT_4BIT
# define INCLUDE_C_GHASH_4BIT
#endif
#define PACK(s) ((size_t)(s)<<(sizeof(size_t)*8-16))
#define REDUCE1BIT(V) do { \
if (sizeof(size_t)==8) { \
u64 T = U64(0xe100000000000000) & (0-(V.lo&1)); \
V.lo = (V.hi<<63)|(V.lo>>1); \
V.hi = (V.hi>>1 )^T; \
} \
else { \
u32 T = 0xe1000000U & (0-(u32)(V.lo&1)); \
V.lo = (V.hi<<63)|(V.lo>>1); \
V.hi = (V.hi>>1 )^((u64)T<<32); \
} \
} while(0)
/*-
*
* NOTE: TABLE_BITS and all non-4bit implementations have been removed in 3.1.
*
* Even though permitted values for TABLE_BITS are 8, 4 and 1, it should
* never be set to 8. 8 is effectively reserved for testing purposes.
* TABLE_BITS>1 are lookup-table-driven implementations referred to as
* "Shoup's" in GCM specification. In other words OpenSSL does not cover
* whole spectrum of possible table driven implementations. Why? In
* non-"Shoup's" case memory access pattern is segmented in such manner,
* that it's trivial to see that cache timing information can reveal
* fair portion of intermediate hash value. Given that ciphertext is
* always available to attacker, it's possible for him to attempt to
* deduce secret parameter H and if successful, tamper with messages
* [which is nothing but trivial in CTR mode]. In "Shoup's" case it's
* not as trivial, but there is no reason to believe that it's resistant
* to cache-timing attack. And the thing about "8-bit" implementation is
* that it consumes 16 (sixteen) times more memory, 4KB per individual
* key + 1KB shared. Well, on pros side it should be twice as fast as
* "4-bit" version. And for gcc-generated x86[_64] code, "8-bit" version
* was observed to run ~75% faster, closer to 100% for commercial
* compilers... Yet "4-bit" procedure is preferred, because it's
* believed to provide better security-performance balance and adequate
* all-round performance. "All-round" refers to things like:
*
* - shorter setup time effectively improves overall timing for
* handling short messages;
* - larger table allocation can become unbearable because of VM
* subsystem penalties (for example on Windows large enough free
* results in VM working set trimming, meaning that consequent
* malloc would immediately incur working set expansion);
* - larger table has larger cache footprint, which can affect
* performance of other code paths (not necessarily even from same
* thread in Hyper-Threading world);
*
* Value of 1 is not appropriate for performance reasons.
*/
static void gcm_init_4bit(u128 Htable[16], const u64 H[2])
{
u128 V;
# if defined(OPENSSL_SMALL_FOOTPRINT)
int i;
# endif
Htable[0].hi = 0;
Htable[0].lo = 0;
V.hi = H[0];
V.lo = H[1];
# if defined(OPENSSL_SMALL_FOOTPRINT)
for (Htable[8] = V, i = 4; i > 0; i >>= 1) {
REDUCE1BIT(V);
Htable[i] = V;
}
for (i = 2; i < 16; i <<= 1) {
u128 *Hi = Htable + i;
int j;
for (V = *Hi, j = 1; j < i; ++j) {
Hi[j].hi = V.hi ^ Htable[j].hi;
Hi[j].lo = V.lo ^ Htable[j].lo;
}
}
# else
Htable[8] = V;
REDUCE1BIT(V);
Htable[4] = V;
REDUCE1BIT(V);
Htable[2] = V;
REDUCE1BIT(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;
# endif
# if defined(GHASH_ASM) && (defined(__arm__) || defined(__arm))
/*
* ARM assembler expects specific dword order in Htable.
*/
{
int j;
DECLARE_IS_ENDIAN;
if (IS_LITTLE_ENDIAN)
for (j = 0; j < 16; ++j) {
V = Htable[j];
Htable[j].hi = V.lo;
Htable[j].lo = V.hi;
} else
for (j = 0; j < 16; ++j) {
V = Htable[j];
Htable[j].hi = V.lo << 32 | V.lo >> 32;
Htable[j].lo = V.hi << 32 | V.hi >> 32;
}
}
# endif
}
# if !defined(GHASH_ASM) || defined(INCLUDE_C_GMULT_4BIT)
static const size_t rem_4bit[16] = {
PACK(0x0000), PACK(0x1C20), PACK(0x3840), PACK(0x2460),
PACK(0x7080), PACK(0x6CA0), PACK(0x48C0), PACK(0x54E0),
PACK(0xE100), PACK(0xFD20), PACK(0xD940), PACK(0xC560),
PACK(0x9180), PACK(0x8DA0), PACK(0xA9C0), PACK(0xB5E0)
};
static void gcm_gmult_4bit(u64 Xi[2], const u128 Htable[16])
{
u128 Z;
int cnt = 15;
size_t rem, nlo, nhi;
DECLARE_IS_ENDIAN;
nlo = ((const u8 *)Xi)[15];
nhi = nlo >> 4;
nlo &= 0xf;
Z.hi = Htable[nlo].hi;
Z.lo = Htable[nlo].lo;
while (1) {
rem = (size_t)Z.lo & 0xf;
Z.lo = (Z.hi << 60) | (Z.lo >> 4);
Z.hi = (Z.hi >> 4);
if (sizeof(size_t) == 8)
Z.hi ^= rem_4bit[rem];
else
Z.hi ^= (u64)rem_4bit[rem] << 32;
Z.hi ^= Htable[nhi].hi;
Z.lo ^= Htable[nhi].lo;
if (--cnt < 0)
break;
nlo = ((const u8 *)Xi)[cnt];
nhi = nlo >> 4;
nlo &= 0xf;
rem = (size_t)Z.lo & 0xf;
Z.lo = (Z.hi << 60) | (Z.lo >> 4);
Z.hi = (Z.hi >> 4);
if (sizeof(size_t) == 8)
Z.hi ^= rem_4bit[rem];
else
Z.hi ^= (u64)rem_4bit[rem] << 32;
Z.hi ^= Htable[nlo].hi;
Z.lo ^= Htable[nlo].lo;
}
if (IS_LITTLE_ENDIAN) {
# ifdef BSWAP8
Xi[0] = BSWAP8(Z.hi);
Xi[1] = BSWAP8(Z.lo);
# else
u8 *p = (u8 *)Xi;
u32 v;
v = (u32)(Z.hi >> 32);
PUTU32(p, v);
v = (u32)(Z.hi);
PUTU32(p + 4, v);
v = (u32)(Z.lo >> 32);
PUTU32(p + 8, v);
v = (u32)(Z.lo);
PUTU32(p + 12, v);
# endif
} else {
Xi[0] = Z.hi;
Xi[1] = Z.lo;
}
}
# endif
# if !defined(GHASH_ASM) || defined(INCLUDE_C_GHASH_4BIT)
# if !defined(OPENSSL_SMALL_FOOTPRINT)
/*
* Streamed gcm_mult_4bit, see CRYPTO_gcm128_[en|de]crypt for
* details... Compiler-generated code doesn't seem to give any
* performance improvement, at least not on x86[_64]. It's here
* mostly as reference and a placeholder for possible future
* non-trivial optimization[s]...
*/
static void gcm_ghash_4bit(u64 Xi[2], const u128 Htable[16],
const u8 *inp, size_t len)
{
u128 Z;
int cnt;
size_t rem, nlo, nhi;
DECLARE_IS_ENDIAN;
do {
cnt = 15;
nlo = ((const u8 *)Xi)[15];
nlo ^= inp[15];
nhi = nlo >> 4;
nlo &= 0xf;
Z.hi = Htable[nlo].hi;
Z.lo = Htable[nlo].lo;
while (1) {
rem = (size_t)Z.lo & 0xf;
Z.lo = (Z.hi << 60) | (Z.lo >> 4);
Z.hi = (Z.hi >> 4);
if (sizeof(size_t) == 8)
Z.hi ^= rem_4bit[rem];
else
Z.hi ^= (u64)rem_4bit[rem] << 32;
Z.hi ^= Htable[nhi].hi;
Z.lo ^= Htable[nhi].lo;
if (--cnt < 0)
break;
nlo = ((const u8 *)Xi)[cnt];
nlo ^= inp[cnt];
nhi = nlo >> 4;
nlo &= 0xf;
rem = (size_t)Z.lo & 0xf;
Z.lo = (Z.hi << 60) | (Z.lo >> 4);
Z.hi = (Z.hi >> 4);
if (sizeof(size_t) == 8)
Z.hi ^= rem_4bit[rem];
else
Z.hi ^= (u64)rem_4bit[rem] << 32;
Z.hi ^= Htable[nlo].hi;
Z.lo ^= Htable[nlo].lo;
}
if (IS_LITTLE_ENDIAN) {
# ifdef BSWAP8
Xi[0] = BSWAP8(Z.hi);
Xi[1] = BSWAP8(Z.lo);
# else
u8 *p = (u8 *)Xi;
u32 v;
v = (u32)(Z.hi >> 32);
PUTU32(p, v);
v = (u32)(Z.hi);
PUTU32(p + 4, v);
v = (u32)(Z.lo >> 32);
PUTU32(p + 8, v);
v = (u32)(Z.lo);
PUTU32(p + 12, v);
# endif
} else {
Xi[0] = Z.hi;
Xi[1] = Z.lo;
}
inp += 16;
/* Block size is 128 bits so len is a multiple of 16 */
len -= 16;
} while (len > 0);
}
# endif
# else
void gcm_gmult_4bit(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_4bit(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
# endif
# define GCM_MUL(ctx) ctx->funcs.gmult(ctx->Xi.u,ctx->Htable)
# if defined(GHASH_ASM) || !defined(OPENSSL_SMALL_FOOTPRINT)
# define GHASH(ctx,in,len) ctx->funcs.ghash((ctx)->Xi.u,(ctx)->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)
# endif
#if (defined(GHASH_ASM) || defined(OPENSSL_CPUID_OBJ))
# if !defined(I386_ONLY) && \
(defined(__i386) || defined(__i386__) || \
defined(__x86_64) || defined(__x86_64__) || \
defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64))
# define GHASH_ASM_X86_OR_64
void gcm_init_clmul(u128 Htable[16], const u64 Xi[2]);
void gcm_gmult_clmul(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_clmul(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
# if defined(__i386) || defined(__i386__) || defined(_M_IX86)
# define gcm_init_avx gcm_init_clmul
# define gcm_gmult_avx gcm_gmult_clmul
# define gcm_ghash_avx gcm_ghash_clmul
# else
void gcm_init_avx(u128 Htable[16], const u64 Xi[2]);
void gcm_gmult_avx(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_avx(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
# endif
# if defined(__i386) || defined(__i386__) || defined(_M_IX86)
# define GHASH_ASM_X86
void gcm_gmult_4bit_mmx(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_4bit_mmx(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
void gcm_gmult_4bit_x86(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_4bit_x86(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
# endif
# elif defined(__arm__) || defined(__arm) || defined(__aarch64__)
# include "arm_arch.h"
# if __ARM_MAX_ARCH__>=7
# define GHASH_ASM_ARM
# define PMULL_CAPABLE (OPENSSL_armcap_P & ARMV8_PMULL)
# if defined(__arm__) || defined(__arm)
# define NEON_CAPABLE (OPENSSL_armcap_P & ARMV7_NEON)
# endif
void gcm_init_neon(u128 Htable[16], const u64 Xi[2]);
void gcm_gmult_neon(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_neon(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
void gcm_init_v8(u128 Htable[16], const u64 Xi[2]);
void gcm_gmult_v8(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_v8(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
# endif
# elif defined(__sparc__) || defined(__sparc)
# include "crypto/sparc_arch.h"
# define GHASH_ASM_SPARC
void gcm_init_vis3(u128 Htable[16], const u64 Xi[2]);
void gcm_gmult_vis3(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_vis3(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
# elif defined(OPENSSL_CPUID_OBJ) && (defined(__powerpc__) || defined(__ppc__) || defined(_ARCH_PPC))
# include "crypto/ppc_arch.h"
# define GHASH_ASM_PPC
void gcm_init_p8(u128 Htable[16], const u64 Xi[2]);
void gcm_gmult_p8(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_p8(u64 Xi[2], const u128 Htable[16], const u8 *inp,
size_t len);
# elif defined(OPENSSL_CPUID_OBJ) && defined(__riscv) && __riscv_xlen == 64
# include "crypto/riscv_arch.h"
# define GHASH_ASM_RV64I
/* Zbc/Zbkc (scalar crypto with clmul) based routines. */
void gcm_init_rv64i_zbc(u128 Htable[16], const u64 Xi[2]);
void gcm_init_rv64i_zbc__zbb(u128 Htable[16], const u64 Xi[2]);
void gcm_init_rv64i_zbc__zbkb(u128 Htable[16], const u64 Xi[2]);
void gcm_gmult_rv64i_zbc(u64 Xi[2], const u128 Htable[16]);
void gcm_gmult_rv64i_zbc__zbkb(u64 Xi[2], const u128 Htable[16]);
void gcm_ghash_rv64i_zbc(u64 Xi[2], const u128 Htable[16],
const u8 *inp, size_t len);
void gcm_ghash_rv64i_zbc__zbkb(u64 Xi[2], const u128 Htable[16],
const u8 *inp, size_t len);
# endif
#endif
static void gcm_get_funcs(struct gcm_funcs_st *ctx)
{
/* set defaults -- overridden below as needed */
ctx->ginit = gcm_init_4bit;
#if !defined(GHASH_ASM)
ctx->gmult = gcm_gmult_4bit;
#else
ctx->gmult = NULL;
#endif
#if !defined(GHASH_ASM) && !defined(OPENSSL_SMALL_FOOTPRINT)
ctx->ghash = gcm_ghash_4bit;
#else
ctx->ghash = NULL;
#endif
#if defined(GHASH_ASM_X86_OR_64)
# if !defined(GHASH_ASM_X86) || defined(OPENSSL_IA32_SSE2)
/* x86_64 */
if (OPENSSL_ia32cap_P[1] & (1 << 1)) { /* check PCLMULQDQ bit */
if (((OPENSSL_ia32cap_P[1] >> 22) & 0x41) == 0x41) { /* AVX+MOVBE */
ctx->ginit = gcm_init_avx;
ctx->gmult = gcm_gmult_avx;
ctx->ghash = gcm_ghash_avx;
} else {
ctx->ginit = gcm_init_clmul;
ctx->gmult = gcm_gmult_clmul;
ctx->ghash = gcm_ghash_clmul;
}
return;
}
# endif
# if defined(GHASH_ASM_X86)
/* x86 only */
# if defined(OPENSSL_IA32_SSE2)
if (OPENSSL_ia32cap_P[0] & (1 << 25)) { /* check SSE bit */
ctx->gmult = gcm_gmult_4bit_mmx;
ctx->ghash = gcm_ghash_4bit_mmx;
return;
}
# else
if (OPENSSL_ia32cap_P[0] & (1 << 23)) { /* check MMX bit */
ctx->gmult = gcm_gmult_4bit_mmx;
ctx->ghash = gcm_ghash_4bit_mmx;
return;
}
# endif
ctx->gmult = gcm_gmult_4bit_x86;
ctx->ghash = gcm_ghash_4bit_x86;
return;
# else
/* x86_64 fallback defaults */
ctx->gmult = gcm_gmult_4bit;
ctx->ghash = gcm_ghash_4bit;
return;
# endif
#elif defined(GHASH_ASM_ARM)
/* ARM defaults */
ctx->gmult = gcm_gmult_4bit;
ctx->ghash = gcm_ghash_4bit;
# ifdef PMULL_CAPABLE
if (PMULL_CAPABLE) {
ctx->ginit = (gcm_init_fn)gcm_init_v8;
ctx->gmult = gcm_gmult_v8;
ctx->ghash = gcm_ghash_v8;
}
# elif defined(NEON_CAPABLE)
if (NEON_CAPABLE) {
ctx->ginit = gcm_init_neon;
ctx->gmult = gcm_gmult_neon;
ctx->ghash = gcm_ghash_neon;
}
# endif
return;
#elif defined(GHASH_ASM_SPARC)
/* SPARC defaults */
ctx->gmult = gcm_gmult_4bit;
ctx->ghash = gcm_ghash_4bit;
if (OPENSSL_sparcv9cap_P[0] & SPARCV9_VIS3) {
ctx->ginit = gcm_init_vis3;
ctx->gmult = gcm_gmult_vis3;
ctx->ghash = gcm_ghash_vis3;
}
return;
#elif defined(GHASH_ASM_PPC)
/* PowerPC does not define GHASH_ASM; defaults set above */
if (OPENSSL_ppccap_P & PPC_CRYPTO207) {
ctx->ginit = gcm_init_p8;
ctx->gmult = gcm_gmult_p8;
ctx->ghash = gcm_ghash_p8;
}
return;
#elif defined(GHASH_ASM_RV64I)
/* RISCV defaults */
ctx->gmult = gcm_gmult_4bit;
ctx->ghash = gcm_ghash_4bit;
if (RISCV_HAS_ZBC()) {
if (RISCV_HAS_ZBKB()) {
ctx->ginit = gcm_init_rv64i_zbc__zbkb;
ctx->gmult = gcm_gmult_rv64i_zbc__zbkb;
ctx->ghash = gcm_ghash_rv64i_zbc__zbkb;
} else if (RISCV_HAS_ZBB()) {
ctx->ginit = gcm_init_rv64i_zbc__zbb;
ctx->gmult = gcm_gmult_rv64i_zbc;
ctx->ghash = gcm_ghash_rv64i_zbc;
} else {
ctx->ginit = gcm_init_rv64i_zbc;
ctx->gmult = gcm_gmult_rv64i_zbc;
ctx->ghash = gcm_ghash_rv64i_zbc;
}
}
return;
#elif defined(GHASH_ASM)
/* all other architectures use the generic names */
ctx->gmult = gcm_gmult_4bit;
ctx->ghash = gcm_ghash_4bit;
return;
#endif
}
void ossl_gcm_init_4bit(u128 Htable[16], const u64 H[2])
{
struct gcm_funcs_st funcs;
gcm_get_funcs(&funcs);
funcs.ginit(Htable, H);
}
void ossl_gcm_gmult_4bit(u64 Xi[2], const u128 Htable[16])
{
struct gcm_funcs_st funcs;
gcm_get_funcs(&funcs);
funcs.gmult(Xi, Htable);
}
void ossl_gcm_ghash_4bit(u64 Xi[2], const u128 Htable[16],
const u8 *inp, size_t len)
{
struct gcm_funcs_st funcs;
u64 tmp[2];
size_t i;
gcm_get_funcs(&funcs);
if (funcs.ghash != NULL) {
funcs.ghash(Xi, Htable, inp, len);
} else {
/* Emulate ghash if needed */
for (i = 0; i < len; i += 16) {
memcpy(tmp, &inp[i], sizeof(tmp));
Xi[0] ^= tmp[0];
Xi[1] ^= tmp[1];
funcs.gmult(Xi, Htable);
}
}
}
void CRYPTO_gcm128_init(GCM128_CONTEXT *ctx, void *key, block128_f block)
{
DECLARE_IS_ENDIAN;
memset(ctx, 0, sizeof(*ctx));
ctx->block = block;
ctx->key = key;
(*block) (ctx->H.c, ctx->H.c, key);
if (IS_LITTLE_ENDIAN) {
/* H is stored in host byte order */
#ifdef BSWAP8
ctx->H.u[0] = BSWAP8(ctx->H.u[0]);
ctx->H.u[1] = BSWAP8(ctx->H.u[1]);
#else
u8 *p = ctx->H.c;
u64 hi, lo;
hi = (u64)GETU32(p) << 32 | GETU32(p + 4);
lo = (u64)GETU32(p + 8) << 32 | GETU32(p + 12);
ctx->H.u[0] = hi;
ctx->H.u[1] = lo;
#endif
}
gcm_get_funcs(&ctx->funcs);
ctx->funcs.ginit(ctx->Htable, ctx->H.u);
}
void CRYPTO_gcm128_setiv(GCM128_CONTEXT *ctx, const unsigned char *iv,
size_t len)
{
DECLARE_IS_ENDIAN;
unsigned int ctr;
ctx->len.u[0] = 0; /* AAD length */
ctx->len.u[1] = 0; /* message length */
ctx->ares = 0;
ctx->mres = 0;
if (len == 12) {
memcpy(ctx->Yi.c, iv, 12);
ctx->Yi.c[12] = 0;
ctx->Yi.c[13] = 0;
ctx->Yi.c[14] = 0;
ctx->Yi.c[15] = 1;
ctr = 1;
} else {
size_t i;
u64 len0 = len;
/* Borrow ctx->Xi to calculate initial Yi */
ctx->Xi.u[0] = 0;
ctx->Xi.u[1] = 0;
while (len >= 16) {
for (i = 0; i < 16; ++i)
ctx->Xi.c[i] ^= iv[i];
GCM_MUL(ctx);
iv += 16;
len -= 16;
}
if (len) {
for (i = 0; i < len; ++i)
ctx->Xi.c[i] ^= iv[i];
GCM_MUL(ctx);
}
len0 <<= 3;
if (IS_LITTLE_ENDIAN) {
#ifdef BSWAP8
ctx->Xi.u[1] ^= BSWAP8(len0);
#else
ctx->Xi.c[8] ^= (u8)(len0 >> 56);
ctx->Xi.c[9] ^= (u8)(len0 >> 48);
ctx->Xi.c[10] ^= (u8)(len0 >> 40);
ctx->Xi.c[11] ^= (u8)(len0 >> 32);
ctx->Xi.c[12] ^= (u8)(len0 >> 24);
ctx->Xi.c[13] ^= (u8)(len0 >> 16);
ctx->Xi.c[14] ^= (u8)(len0 >> 8);
ctx->Xi.c[15] ^= (u8)(len0);
#endif
} else {
ctx->Xi.u[1] ^= len0;
}
GCM_MUL(ctx);
if (IS_LITTLE_ENDIAN)
#ifdef BSWAP4
ctr = BSWAP4(ctx->Xi.d[3]);
#else
ctr = GETU32(ctx->Xi.c + 12);
#endif
else
ctr = ctx->Xi.d[3];
/* Copy borrowed Xi to Yi */
ctx->Yi.u[0] = ctx->Xi.u[0];
ctx->Yi.u[1] = ctx->Xi.u[1];
}
ctx->Xi.u[0] = 0;
ctx->Xi.u[1] = 0;
(*ctx->block) (ctx->Yi.c, ctx->EK0.c, ctx->key);
++ctr;
if (IS_LITTLE_ENDIAN)
#ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
#else
PUTU32(ctx->Yi.c + 12, ctr);
#endif
else
ctx->Yi.d[3] = ctr;
}
int CRYPTO_gcm128_aad(GCM128_CONTEXT *ctx, const unsigned char *aad,
size_t len)
{
size_t i;
unsigned int n;
u64 alen = ctx->len.u[0];
if (ctx->len.u[1])
return -2;
alen += len;
if (alen > (U64(1) << 61) || (sizeof(len) == 8 && alen < len))
return -1;
ctx->len.u[0] = alen;
n = ctx->ares;
if (n) {
while (n && len) {
ctx->Xi.c[n] ^= *(aad++);
--len;
n = (n + 1) % 16;
}
if (n == 0)
GCM_MUL(ctx);
else {
ctx->ares = n;
return 0;
}
}
#ifdef GHASH
if ((i = (len & (size_t)-16))) {
GHASH(ctx, aad, i);
aad += i;
len -= i;
}
#else
while (len >= 16) {
for (i = 0; i < 16; ++i)
ctx->Xi.c[i] ^= aad[i];
GCM_MUL(ctx);
aad += 16;
len -= 16;
}
#endif
if (len) {
n = (unsigned int)len;
for (i = 0; i < len; ++i)
ctx->Xi.c[i] ^= aad[i];
}
ctx->ares = n;
return 0;
}
int CRYPTO_gcm128_encrypt(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len)
{
DECLARE_IS_ENDIAN;
unsigned int n, ctr, mres;
size_t i;
u64 mlen = ctx->len.u[1];
block128_f block = ctx->block;
void *key = ctx->key;
mlen += len;
if (mlen > ((U64(1) << 36) - 32) || (sizeof(len) == 8 && mlen < len))
return -1;
ctx->len.u[1] = mlen;
mres = ctx->mres;
if (ctx->ares) {
/* First call to encrypt finalizes GHASH(AAD) */
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
if (len == 0) {
GCM_MUL(ctx);
ctx->ares = 0;
return 0;
}
memcpy(ctx->Xn, ctx->Xi.c, sizeof(ctx->Xi));
ctx->Xi.u[0] = 0;
ctx->Xi.u[1] = 0;
mres = sizeof(ctx->Xi);
#else
GCM_MUL(ctx);
#endif
ctx->ares = 0;
}
if (IS_LITTLE_ENDIAN)
#ifdef BSWAP4
ctr = BSWAP4(ctx->Yi.d[3]);
#else
ctr = GETU32(ctx->Yi.c + 12);
#endif
else
ctr = ctx->Yi.d[3];
n = mres % 16;
#if !defined(OPENSSL_SMALL_FOOTPRINT)
if (16 % sizeof(size_t) == 0) { /* always true actually */
do {
if (n) {
# if defined(GHASH)
while (n && len) {
ctx->Xn[mres++] = *(out++) = *(in++) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
} else {
ctx->mres = mres;
return 0;
}
# else
while (n && len) {
ctx->Xi.c[n] ^= *(out++) = *(in++) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx);
mres = 0;
} else {
ctx->mres = n;
return 0;
}
# endif
}
# if defined(STRICT_ALIGNMENT)
if (((size_t)in | (size_t)out) % sizeof(size_t) != 0)
break;
# endif
# if defined(GHASH)
if (len >= 16 && mres) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
}
# if defined(GHASH_CHUNK)
while (len >= GHASH_CHUNK) {
size_t j = GHASH_CHUNK;
while (j) {
size_t_aX *out_t = (size_t_aX *)out;
const size_t_aX *in_t = (const size_t_aX *)in;
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
for (i = 0; i < 16 / sizeof(size_t); ++i)
out_t[i] = in_t[i] ^ ctx->EKi.t[i];
out += 16;
in += 16;
j -= 16;
}
GHASH(ctx, out - GHASH_CHUNK, GHASH_CHUNK);
len -= GHASH_CHUNK;
}
# endif
if ((i = (len & (size_t)-16))) {
size_t j = i;
while (len >= 16) {
size_t_aX *out_t = (size_t_aX *)out;
const size_t_aX *in_t = (const size_t_aX *)in;
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
for (i = 0; i < 16 / sizeof(size_t); ++i)
out_t[i] = in_t[i] ^ ctx->EKi.t[i];
out += 16;
in += 16;
len -= 16;
}
GHASH(ctx, out - j, j);
}
# else
while (len >= 16) {
size_t *out_t = (size_t *)out;
const size_t *in_t = (const size_t *)in;
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
for (i = 0; i < 16 / sizeof(size_t); ++i)
ctx->Xi.t[i] ^= out_t[i] = in_t[i] ^ ctx->EKi.t[i];
GCM_MUL(ctx);
out += 16;
in += 16;
len -= 16;
}
# endif
if (len) {
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
# if defined(GHASH)
while (len--) {
ctx->Xn[mres++] = out[n] = in[n] ^ ctx->EKi.c[n];
++n;
}
# else
while (len--) {
ctx->Xi.c[n] ^= out[n] = in[n] ^ ctx->EKi.c[n];
++n;
}
mres = n;
# endif
}
ctx->mres = mres;
return 0;
} while (0);
}
#endif
for (i = 0; i < len; ++i) {
if (n == 0) {
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
#ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
#else
PUTU32(ctx->Yi.c + 12, ctr);
#endif
else
ctx->Yi.d[3] = ctr;
}
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
ctx->Xn[mres++] = out[i] = in[i] ^ ctx->EKi.c[n];
n = (n + 1) % 16;
if (mres == sizeof(ctx->Xn)) {
GHASH(ctx,ctx->Xn,sizeof(ctx->Xn));
mres = 0;
}
#else
ctx->Xi.c[n] ^= out[i] = in[i] ^ ctx->EKi.c[n];
mres = n = (n + 1) % 16;
if (n == 0)
GCM_MUL(ctx);
#endif
}
ctx->mres = mres;
return 0;
}
int CRYPTO_gcm128_decrypt(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len)
{
DECLARE_IS_ENDIAN;
unsigned int n, ctr, mres;
size_t i;
u64 mlen = ctx->len.u[1];
block128_f block = ctx->block;
void *key = ctx->key;
mlen += len;
if (mlen > ((U64(1) << 36) - 32) || (sizeof(len) == 8 && mlen < len))
return -1;
ctx->len.u[1] = mlen;
mres = ctx->mres;
if (ctx->ares) {
/* First call to decrypt finalizes GHASH(AAD) */
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
if (len == 0) {
GCM_MUL(ctx);
ctx->ares = 0;
return 0;
}
memcpy(ctx->Xn, ctx->Xi.c, sizeof(ctx->Xi));
ctx->Xi.u[0] = 0;
ctx->Xi.u[1] = 0;
mres = sizeof(ctx->Xi);
#else
GCM_MUL(ctx);
#endif
ctx->ares = 0;
}
if (IS_LITTLE_ENDIAN)
#ifdef BSWAP4
ctr = BSWAP4(ctx->Yi.d[3]);
#else
ctr = GETU32(ctx->Yi.c + 12);
#endif
else
ctr = ctx->Yi.d[3];
n = mres % 16;
#if !defined(OPENSSL_SMALL_FOOTPRINT)
if (16 % sizeof(size_t) == 0) { /* always true actually */
do {
if (n) {
# if defined(GHASH)
while (n && len) {
*(out++) = (ctx->Xn[mres++] = *(in++)) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
} else {
ctx->mres = mres;
return 0;
}
# else
while (n && len) {
u8 c = *(in++);
*(out++) = c ^ ctx->EKi.c[n];
ctx->Xi.c[n] ^= c;
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx);
mres = 0;
} else {
ctx->mres = n;
return 0;
}
# endif
}
# if defined(STRICT_ALIGNMENT)
if (((size_t)in | (size_t)out) % sizeof(size_t) != 0)
break;
# endif
# if defined(GHASH)
if (len >= 16 && mres) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
}
# if defined(GHASH_CHUNK)
while (len >= GHASH_CHUNK) {
size_t j = GHASH_CHUNK;
GHASH(ctx, in, GHASH_CHUNK);
while (j) {
size_t_aX *out_t = (size_t_aX *)out;
const size_t_aX *in_t = (const size_t_aX *)in;
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
for (i = 0; i < 16 / sizeof(size_t); ++i)
out_t[i] = in_t[i] ^ ctx->EKi.t[i];
out += 16;
in += 16;
j -= 16;
}
len -= GHASH_CHUNK;
}
# endif
if ((i = (len & (size_t)-16))) {
GHASH(ctx, in, i);
while (len >= 16) {
size_t_aX *out_t = (size_t_aX *)out;
const size_t_aX *in_t = (const size_t_aX *)in;
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
for (i = 0; i < 16 / sizeof(size_t); ++i)
out_t[i] = in_t[i] ^ ctx->EKi.t[i];
out += 16;
in += 16;
len -= 16;
}
}
# else
while (len >= 16) {
size_t *out_t = (size_t *)out;
const size_t *in_t = (const size_t *)in;
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
for (i = 0; i < 16 / sizeof(size_t); ++i) {
size_t c = in_t[i];
out_t[i] = c ^ ctx->EKi.t[i];
ctx->Xi.t[i] ^= c;
}
GCM_MUL(ctx);
out += 16;
in += 16;
len -= 16;
}
# endif
if (len) {
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
# if defined(GHASH)
while (len--) {
out[n] = (ctx->Xn[mres++] = in[n]) ^ ctx->EKi.c[n];
++n;
}
# else
while (len--) {
u8 c = in[n];
ctx->Xi.c[n] ^= c;
out[n] = c ^ ctx->EKi.c[n];
++n;
}
mres = n;
# endif
}
ctx->mres = mres;
return 0;
} while (0);
}
#endif
for (i = 0; i < len; ++i) {
u8 c;
if (n == 0) {
(*block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
#ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
#else
PUTU32(ctx->Yi.c + 12, ctr);
#endif
else
ctx->Yi.d[3] = ctr;
}
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
out[i] = (ctx->Xn[mres++] = c = in[i]) ^ ctx->EKi.c[n];
n = (n + 1) % 16;
if (mres == sizeof(ctx->Xn)) {
GHASH(ctx,ctx->Xn,sizeof(ctx->Xn));
mres = 0;
}
#else
c = in[i];
out[i] = c ^ ctx->EKi.c[n];
ctx->Xi.c[n] ^= c;
mres = n = (n + 1) % 16;
if (n == 0)
GCM_MUL(ctx);
#endif
}
ctx->mres = mres;
return 0;
}
int CRYPTO_gcm128_encrypt_ctr32(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len, ctr128_f stream)
{
#if defined(OPENSSL_SMALL_FOOTPRINT)
return CRYPTO_gcm128_encrypt(ctx, in, out, len);
#else
DECLARE_IS_ENDIAN;
unsigned int n, ctr, mres;
size_t i;
u64 mlen = ctx->len.u[1];
void *key = ctx->key;
mlen += len;
if (mlen > ((U64(1) << 36) - 32) || (sizeof(len) == 8 && mlen < len))
return -1;
ctx->len.u[1] = mlen;
mres = ctx->mres;
if (ctx->ares) {
/* First call to encrypt finalizes GHASH(AAD) */
#if defined(GHASH)
if (len == 0) {
GCM_MUL(ctx);
ctx->ares = 0;
return 0;
}
memcpy(ctx->Xn, ctx->Xi.c, sizeof(ctx->Xi));
ctx->Xi.u[0] = 0;
ctx->Xi.u[1] = 0;
mres = sizeof(ctx->Xi);
#else
GCM_MUL(ctx);
#endif
ctx->ares = 0;
}
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctr = BSWAP4(ctx->Yi.d[3]);
# else
ctr = GETU32(ctx->Yi.c + 12);
# endif
else
ctr = ctx->Yi.d[3];
n = mres % 16;
if (n) {
# if defined(GHASH)
while (n && len) {
ctx->Xn[mres++] = *(out++) = *(in++) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
} else {
ctx->mres = mres;
return 0;
}
# else
while (n && len) {
ctx->Xi.c[n] ^= *(out++) = *(in++) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx);
mres = 0;
} else {
ctx->mres = n;
return 0;
}
# endif
}
# if defined(GHASH)
if (len >= 16 && mres) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
}
# if defined(GHASH_CHUNK)
while (len >= GHASH_CHUNK) {
(*stream) (in, out, GHASH_CHUNK / 16, key, ctx->Yi.c);
ctr += GHASH_CHUNK / 16;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
GHASH(ctx, out, GHASH_CHUNK);
out += GHASH_CHUNK;
in += GHASH_CHUNK;
len -= GHASH_CHUNK;
}
# endif
# endif
if ((i = (len & (size_t)-16))) {
size_t j = i / 16;
(*stream) (in, out, j, key, ctx->Yi.c);
ctr += (unsigned int)j;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
in += i;
len -= i;
# if defined(GHASH)
GHASH(ctx, out, i);
out += i;
# else
while (j--) {
for (i = 0; i < 16; ++i)
ctx->Xi.c[i] ^= out[i];
GCM_MUL(ctx);
out += 16;
}
# endif
}
if (len) {
(*ctx->block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
while (len--) {
# if defined(GHASH)
ctx->Xn[mres++] = out[n] = in[n] ^ ctx->EKi.c[n];
# else
ctx->Xi.c[mres++] ^= out[n] = in[n] ^ ctx->EKi.c[n];
# endif
++n;
}
}
ctx->mres = mres;
return 0;
#endif
}
int CRYPTO_gcm128_decrypt_ctr32(GCM128_CONTEXT *ctx,
const unsigned char *in, unsigned char *out,
size_t len, ctr128_f stream)
{
#if defined(OPENSSL_SMALL_FOOTPRINT)
return CRYPTO_gcm128_decrypt(ctx, in, out, len);
#else
DECLARE_IS_ENDIAN;
unsigned int n, ctr, mres;
size_t i;
u64 mlen = ctx->len.u[1];
void *key = ctx->key;
mlen += len;
if (mlen > ((U64(1) << 36) - 32) || (sizeof(len) == 8 && mlen < len))
return -1;
ctx->len.u[1] = mlen;
mres = ctx->mres;
if (ctx->ares) {
/* First call to decrypt finalizes GHASH(AAD) */
# if defined(GHASH)
if (len == 0) {
GCM_MUL(ctx);
ctx->ares = 0;
return 0;
}
memcpy(ctx->Xn, ctx->Xi.c, sizeof(ctx->Xi));
ctx->Xi.u[0] = 0;
ctx->Xi.u[1] = 0;
mres = sizeof(ctx->Xi);
# else
GCM_MUL(ctx);
# endif
ctx->ares = 0;
}
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctr = BSWAP4(ctx->Yi.d[3]);
# else
ctr = GETU32(ctx->Yi.c + 12);
# endif
else
ctr = ctx->Yi.d[3];
n = mres % 16;
if (n) {
# if defined(GHASH)
while (n && len) {
*(out++) = (ctx->Xn[mres++] = *(in++)) ^ ctx->EKi.c[n];
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
} else {
ctx->mres = mres;
return 0;
}
# else
while (n && len) {
u8 c = *(in++);
*(out++) = c ^ ctx->EKi.c[n];
ctx->Xi.c[n] ^= c;
--len;
n = (n + 1) % 16;
}
if (n == 0) {
GCM_MUL(ctx);
mres = 0;
} else {
ctx->mres = n;
return 0;
}
# endif
}
# if defined(GHASH)
if (len >= 16 && mres) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
}
# if defined(GHASH_CHUNK)
while (len >= GHASH_CHUNK) {
GHASH(ctx, in, GHASH_CHUNK);
(*stream) (in, out, GHASH_CHUNK / 16, key, ctx->Yi.c);
ctr += GHASH_CHUNK / 16;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
out += GHASH_CHUNK;
in += GHASH_CHUNK;
len -= GHASH_CHUNK;
}
# endif
# endif
if ((i = (len & (size_t)-16))) {
size_t j = i / 16;
# if defined(GHASH)
GHASH(ctx, in, i);
# else
while (j--) {
size_t k;
for (k = 0; k < 16; ++k)
ctx->Xi.c[k] ^= in[k];
GCM_MUL(ctx);
in += 16;
}
j = i / 16;
in -= i;
# endif
(*stream) (in, out, j, key, ctx->Yi.c);
ctr += (unsigned int)j;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
out += i;
in += i;
len -= i;
}
if (len) {
(*ctx->block) (ctx->Yi.c, ctx->EKi.c, key);
++ctr;
if (IS_LITTLE_ENDIAN)
# ifdef BSWAP4
ctx->Yi.d[3] = BSWAP4(ctr);
# else
PUTU32(ctx->Yi.c + 12, ctr);
# endif
else
ctx->Yi.d[3] = ctr;
while (len--) {
# if defined(GHASH)
out[n] = (ctx->Xn[mres++] = in[n]) ^ ctx->EKi.c[n];
# else
u8 c = in[n];
ctx->Xi.c[mres++] ^= c;
out[n] = c ^ ctx->EKi.c[n];
# endif
++n;
}
}
ctx->mres = mres;
return 0;
#endif
}
int CRYPTO_gcm128_finish(GCM128_CONTEXT *ctx, const unsigned char *tag,
size_t len)
{
DECLARE_IS_ENDIAN;
u64 alen = ctx->len.u[0] << 3;
u64 clen = ctx->len.u[1] << 3;
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
u128 bitlen;
unsigned int mres = ctx->mres;
if (mres) {
unsigned blocks = (mres + 15) & -16;
memset(ctx->Xn + mres, 0, blocks - mres);
mres = blocks;
if (mres == sizeof(ctx->Xn)) {
GHASH(ctx, ctx->Xn, mres);
mres = 0;
}
} else if (ctx->ares) {
GCM_MUL(ctx);
}
#else
if (ctx->mres || ctx->ares)
GCM_MUL(ctx);
#endif
if (IS_LITTLE_ENDIAN) {
#ifdef BSWAP8
alen = BSWAP8(alen);
clen = BSWAP8(clen);
#else
u8 *p = ctx->len.c;
ctx->len.u[0] = alen;
ctx->len.u[1] = clen;
alen = (u64)GETU32(p) << 32 | GETU32(p + 4);
clen = (u64)GETU32(p + 8) << 32 | GETU32(p + 12);
#endif
}
#if defined(GHASH) && !defined(OPENSSL_SMALL_FOOTPRINT)
bitlen.hi = alen;
bitlen.lo = clen;
memcpy(ctx->Xn + mres, &bitlen, sizeof(bitlen));
mres += sizeof(bitlen);
GHASH(ctx, ctx->Xn, mres);
#else
ctx->Xi.u[0] ^= alen;
ctx->Xi.u[1] ^= clen;
GCM_MUL(ctx);
#endif
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);
else
return -1;
}
void CRYPTO_gcm128_tag(GCM128_CONTEXT *ctx, unsigned char *tag, size_t len)
{
CRYPTO_gcm128_finish(ctx, NULL, 0);
memcpy(tag, ctx->Xi.c,
len <= sizeof(ctx->Xi.c) ? len : sizeof(ctx->Xi.c));
}
GCM128_CONTEXT *CRYPTO_gcm128_new(void *key, block128_f block)
{
GCM128_CONTEXT *ret;
if ((ret = OPENSSL_malloc(sizeof(*ret))) != NULL)
CRYPTO_gcm128_init(ret, key, block);
return ret;
}
void CRYPTO_gcm128_release(GCM128_CONTEXT *ctx)
{
OPENSSL_clear_free(ctx, sizeof(*ctx));
}
