/*
* Copyright (c) 2017 Thomas Pornin <pornin@bolet.org>
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#define BR_ENABLE_INTRINSICS 1
#include "inner.h"
/*
* This code contains the AES key schedule implementation using the
* AES-NI opcodes.
*/
#if BR_AES_X86NI
/* see inner.h */
int
br_aes_x86ni_supported(void)
{
/*
* Bit mask for features in ECX:
* 19 SSE4.1 (used for _mm_insert_epi32(), for AES-CTR)
* 25 AES-NI
*/
return br_cpuid(0, 0, 0x02080000, 0);
}
BR_TARGETS_X86_UP
BR_TARGET("sse2,aes")
static inline __m128i
expand_step128(__m128i k, __m128i k2)
{
k = _mm_xor_si128(k, _mm_slli_si128(k, 4));
k = _mm_xor_si128(k, _mm_slli_si128(k, 4));
k = _mm_xor_si128(k, _mm_slli_si128(k, 4));
k2 = _mm_shuffle_epi32(k2, 0xFF);
return _mm_xor_si128(k, k2);
}
BR_TARGET("sse2,aes")
static inline void
expand_step192(__m128i *t1, __m128i *t2, __m128i *t3)
{
__m128i t4;
*t2 = _mm_shuffle_epi32(*t2, 0x55);
t4 = _mm_slli_si128(*t1, 0x4);
*t1 = _mm_xor_si128(*t1, t4);
t4 = _mm_slli_si128(t4, 0x4);
*t1 = _mm_xor_si128(*t1, t4);
t4 = _mm_slli_si128(t4, 0x4);
*t1 = _mm_xor_si128(*t1, t4);
*t1 = _mm_xor_si128(*t1, *t2);
*t2 = _mm_shuffle_epi32(*t1, 0xFF);
t4 = _mm_slli_si128(*t3, 0x4);
*t3 = _mm_xor_si128(*t3, t4);
*t3 = _mm_xor_si128(*t3, *t2);
}
BR_TARGET("sse2,aes")
static inline void
expand_step256_1(__m128i *t1, __m128i *t2)
{
__m128i t4;
*t2 = _mm_shuffle_epi32(*t2, 0xFF);
t4 = _mm_slli_si128(*t1, 0x4);
*t1 = _mm_xor_si128(*t1, t4);
t4 = _mm_slli_si128(t4, 0x4);
*t1 = _mm_xor_si128(*t1, t4);
t4 = _mm_slli_si128(t4, 0x4);
*t1 = _mm_xor_si128(*t1, t4);
*t1 = _mm_xor_si128(*t1, *t2);
}
BR_TARGET("sse2,aes")
static inline void
expand_step256_2(__m128i *t1, __m128i *t3)
{
__m128i t2, t4;
t4 = _mm_aeskeygenassist_si128(*t1, 0x0);
t2 = _mm_shuffle_epi32(t4, 0xAA);
t4 = _mm_slli_si128(*t3, 0x4);
*t3 = _mm_xor_si128(*t3, t4);
t4 = _mm_slli_si128(t4, 0x4);
*t3 = _mm_xor_si128(*t3, t4);
t4 = _mm_slli_si128(t4, 0x4);
*t3 = _mm_xor_si128(*t3, t4);
*t3 = _mm_xor_si128(*t3, t2);
}
/*
* Perform key schedule for AES, encryption direction. Subkeys are written
* in sk[], and the number of rounds is returned. Key length MUST be 16,
* 24 or 32 bytes.
*/
BR_TARGET("sse2,aes")
static unsigned
x86ni_keysched(__m128i *sk, const void *key, size_t len)
{
const unsigned char *kb;
#define KEXP128(k, i, rcon) do { \
k = expand_step128(k, _mm_aeskeygenassist_si128(k, rcon)); \
sk[i] = k; \
} while (0)
#define KEXP192(i, rcon1, rcon2) do { \
sk[(i) + 0] = t1; \
sk[(i) + 1] = t3; \
t2 = _mm_aeskeygenassist_si128(t3, rcon1); \
expand_step192(&t1, &t2, &t3); \
sk[(i) + 1] = _mm_castpd_si128(_mm_shuffle_pd( \
_mm_castsi128_pd(sk[(i) + 1]), \
_mm_castsi128_pd(t1), 0)); \
sk[(i) + 2] = _mm_castpd_si128(_mm_shuffle_pd( \
_mm_castsi128_pd(t1), \
_mm_castsi128_pd(t3), 1)); \
t2 = _mm_aeskeygenassist_si128(t3, rcon2); \
expand_step192(&t1, &t2, &t3); \
} while (0)
#define KEXP256(i, rcon) do { \
sk[(i) + 0] = t3; \
t2 = _mm_aeskeygenassist_si128(t3, rcon); \
expand_step256_1(&t1, &t2); \
sk[(i) + 1] = t1; \
expand_step256_2(&t1, &t3); \
} while (0)
kb = key;
switch (len) {
__m128i t1, t2, t3;
case 16:
t1 = _mm_loadu_si128((const void *)kb);
sk[0] = t1;
KEXP128(t1, 1, 0x01);
KEXP128(t1, 2, 0x02);
KEXP128(t1, 3, 0x04);
KEXP128(t1, 4, 0x08);
KEXP128(t1, 5, 0x10);
KEXP128(t1, 6, 0x20);
KEXP128(t1, 7, 0x40);
KEXP128(t1, 8, 0x80);
KEXP128(t1, 9, 0x1B);
KEXP128(t1, 10, 0x36);
return 10;
case 24:
t1 = _mm_loadu_si128((const void *)kb);
t3 = _mm_loadu_si128((const void *)(kb + 8));
t3 = _mm_shuffle_epi32(t3, 0x4E);
KEXP192(0, 0x01, 0x02);
KEXP192(3, 0x04, 0x08);
KEXP192(6, 0x10, 0x20);
KEXP192(9, 0x40, 0x80);
sk[12] = t1;
return 12;
case 32:
t1 = _mm_loadu_si128((const void *)kb);
t3 = _mm_loadu_si128((const void *)(kb + 16));
sk[0] = t1;
KEXP256( 1, 0x01);
KEXP256( 3, 0x02);
KEXP256( 5, 0x04);
KEXP256( 7, 0x08);
KEXP256( 9, 0x10);
KEXP256(11, 0x20);
sk[13] = t3;
t2 = _mm_aeskeygenassist_si128(t3, 0x40);
expand_step256_1(&t1, &t2);
sk[14] = t1;
return 14;
default:
return 0;
}
#undef KEXP128
#undef KEXP192
#undef KEXP256
}
/* see inner.h */
BR_TARGET("sse2,aes")
unsigned
br_aes_x86ni_keysched_enc(unsigned char *skni, const void *key, size_t len)
{
__m128i sk[15];
unsigned num_rounds;
num_rounds = x86ni_keysched(sk, key, len);
memcpy(skni, sk, (num_rounds + 1) << 4);
return num_rounds;
}
/* see inner.h */
BR_TARGET("sse2,aes")
unsigned
br_aes_x86ni_keysched_dec(unsigned char *skni, const void *key, size_t len)
{
__m128i sk[15];
unsigned u, num_rounds;
num_rounds = x86ni_keysched(sk, key, len);
_mm_storeu_si128((void *)skni, sk[num_rounds]);
for (u = 1; u < num_rounds; u ++) {
_mm_storeu_si128((void *)(skni + (u << 4)),
_mm_aesimc_si128(sk[num_rounds - u]));
}
_mm_storeu_si128((void *)(skni + (num_rounds << 4)), sk[0]);
return num_rounds;
}
BR_TARGETS_X86_DOWN
#endif