| /* |
| * copyright (c) 2007 Michael Niedermayer <michaelni@gmx.at> |
| * |
| * some optimization ideas from aes128.c by Reimar Doeffinger |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include "common.h" |
| #include "aes.h" |
| #include "aes_internal.h" |
| #include "intreadwrite.h" |
| #include "timer.h" |
| |
| const int av_aes_size= sizeof(AVAES); |
| |
| struct AVAES *av_aes_alloc(void) |
| { |
| return av_mallocz(sizeof(struct AVAES)); |
| } |
| |
| static const uint8_t rcon[10] = { |
| 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 |
| }; |
| |
| static uint8_t sbox[256]; |
| static uint8_t inv_sbox[256]; |
| #if CONFIG_SMALL |
| static uint32_t enc_multbl[1][256]; |
| static uint32_t dec_multbl[1][256]; |
| #else |
| static uint32_t enc_multbl[4][256]; |
| static uint32_t dec_multbl[4][256]; |
| #endif |
| |
| #if HAVE_BIGENDIAN |
| # define ROT(x, s) (((x) >> (s)) | ((x) << (32-(s)))) |
| #else |
| # define ROT(x, s) (((x) << (s)) | ((x) >> (32-(s)))) |
| #endif |
| |
| static inline void addkey(av_aes_block *dst, const av_aes_block *src, |
| const av_aes_block *round_key) |
| { |
| dst->u64[0] = src->u64[0] ^ round_key->u64[0]; |
| dst->u64[1] = src->u64[1] ^ round_key->u64[1]; |
| } |
| |
| static inline void addkey_s(av_aes_block *dst, const uint8_t *src, |
| const av_aes_block *round_key) |
| { |
| dst->u64[0] = AV_RN64(src) ^ round_key->u64[0]; |
| dst->u64[1] = AV_RN64(src + 8) ^ round_key->u64[1]; |
| } |
| |
| static inline void addkey_d(uint8_t *dst, const av_aes_block *src, |
| const av_aes_block *round_key) |
| { |
| AV_WN64(dst, src->u64[0] ^ round_key->u64[0]); |
| AV_WN64(dst + 8, src->u64[1] ^ round_key->u64[1]); |
| } |
| |
| static void subshift(av_aes_block s0[2], int s, const uint8_t *box) |
| { |
| av_aes_block *s1 = (av_aes_block *) (s0[0].u8 - s); |
| av_aes_block *s3 = (av_aes_block *) (s0[0].u8 + s); |
| |
| s0[0].u8[ 0] = box[s0[1].u8[ 0]]; |
| s0[0].u8[ 4] = box[s0[1].u8[ 4]]; |
| s0[0].u8[ 8] = box[s0[1].u8[ 8]]; |
| s0[0].u8[12] = box[s0[1].u8[12]]; |
| s1[0].u8[ 3] = box[s1[1].u8[ 7]]; |
| s1[0].u8[ 7] = box[s1[1].u8[11]]; |
| s1[0].u8[11] = box[s1[1].u8[15]]; |
| s1[0].u8[15] = box[s1[1].u8[ 3]]; |
| s0[0].u8[ 2] = box[s0[1].u8[10]]; |
| s0[0].u8[10] = box[s0[1].u8[ 2]]; |
| s0[0].u8[ 6] = box[s0[1].u8[14]]; |
| s0[0].u8[14] = box[s0[1].u8[ 6]]; |
| s3[0].u8[ 1] = box[s3[1].u8[13]]; |
| s3[0].u8[13] = box[s3[1].u8[ 9]]; |
| s3[0].u8[ 9] = box[s3[1].u8[ 5]]; |
| s3[0].u8[ 5] = box[s3[1].u8[ 1]]; |
| } |
| |
| static inline int mix_core(uint32_t multbl[][256], int a, int b, int c, int d){ |
| #if CONFIG_SMALL |
| return multbl[0][a] ^ ROT(multbl[0][b], 8) ^ ROT(multbl[0][c], 16) ^ ROT(multbl[0][d], 24); |
| #else |
| return multbl[0][a] ^ multbl[1][b] ^ multbl[2][c] ^ multbl[3][d]; |
| #endif |
| } |
| |
| static inline void mix(av_aes_block state[2], uint32_t multbl[][256], int s1, int s3){ |
| uint8_t (*src)[4] = state[1].u8x4; |
| state[0].u32[0] = mix_core(multbl, src[0][0], src[s1 ][1], src[2][2], src[s3 ][3]); |
| state[0].u32[1] = mix_core(multbl, src[1][0], src[s3-1][1], src[3][2], src[s1-1][3]); |
| state[0].u32[2] = mix_core(multbl, src[2][0], src[s3 ][1], src[0][2], src[s1 ][3]); |
| state[0].u32[3] = mix_core(multbl, src[3][0], src[s1-1][1], src[1][2], src[s3-1][3]); |
| } |
| |
| static inline void aes_crypt(AVAES *a, int s, const uint8_t *sbox, |
| uint32_t multbl[][256]) |
| { |
| int r; |
| |
| for (r = a->rounds - 1; r > 0; r--) { |
| mix(a->state, multbl, 3 - s, 1 + s); |
| addkey(&a->state[1], &a->state[0], &a->round_key[r]); |
| } |
| |
| subshift(&a->state[0], s, sbox); |
| } |
| |
| static void aes_encrypt(AVAES *a, uint8_t *dst, const uint8_t *src, |
| int count, uint8_t *iv, int rounds) |
| { |
| while (count--) { |
| addkey_s(&a->state[1], src, &a->round_key[rounds]); |
| if (iv) |
| addkey_s(&a->state[1], iv, &a->state[1]); |
| aes_crypt(a, 2, sbox, enc_multbl); |
| addkey_d(dst, &a->state[0], &a->round_key[0]); |
| if (iv) |
| memcpy(iv, dst, 16); |
| src += 16; |
| dst += 16; |
| } |
| } |
| |
| static void aes_decrypt(AVAES *a, uint8_t *dst, const uint8_t *src, |
| int count, uint8_t *iv, int rounds) |
| { |
| while (count--) { |
| addkey_s(&a->state[1], src, &a->round_key[rounds]); |
| aes_crypt(a, 0, inv_sbox, dec_multbl); |
| if (iv) { |
| addkey_s(&a->state[0], iv, &a->state[0]); |
| memcpy(iv, src, 16); |
| } |
| addkey_d(dst, &a->state[0], &a->round_key[0]); |
| src += 16; |
| dst += 16; |
| } |
| } |
| |
| void av_aes_crypt(AVAES *a, uint8_t *dst, const uint8_t *src, |
| int count, uint8_t *iv, int decrypt) |
| { |
| a->crypt(a, dst, src, count, iv, a->rounds); |
| } |
| |
| static void init_multbl2(uint32_t tbl[][256], const int c[4], |
| const uint8_t *log8, const uint8_t *alog8, |
| const uint8_t *sbox) |
| { |
| int i; |
| |
| for (i = 0; i < 256; i++) { |
| int x = sbox[i]; |
| if (x) { |
| int k, l, m, n; |
| x = log8[x]; |
| k = alog8[x + log8[c[0]]]; |
| l = alog8[x + log8[c[1]]]; |
| m = alog8[x + log8[c[2]]]; |
| n = alog8[x + log8[c[3]]]; |
| tbl[0][i] = AV_NE(MKBETAG(k,l,m,n), MKTAG(k,l,m,n)); |
| #if !CONFIG_SMALL |
| tbl[1][i] = ROT(tbl[0][i], 8); |
| tbl[2][i] = ROT(tbl[0][i], 16); |
| tbl[3][i] = ROT(tbl[0][i], 24); |
| #endif |
| } |
| } |
| } |
| |
| // this is based on the reference AES code by Paulo Barreto and Vincent Rijmen |
| int av_aes_init(AVAES *a, const uint8_t *key, int key_bits, int decrypt) |
| { |
| int i, j, t, rconpointer = 0; |
| uint8_t tk[8][4]; |
| int KC = key_bits >> 5; |
| int rounds = KC + 6; |
| uint8_t log8[256]; |
| uint8_t alog8[512]; |
| |
| a->crypt = decrypt ? aes_decrypt : aes_encrypt; |
| |
| if (!enc_multbl[FF_ARRAY_ELEMS(enc_multbl)-1][FF_ARRAY_ELEMS(enc_multbl[0])-1]) { |
| j = 1; |
| for (i = 0; i < 255; i++) { |
| alog8[i] = alog8[i + 255] = j; |
| log8[j] = i; |
| j ^= j + j; |
| if (j > 255) |
| j ^= 0x11B; |
| } |
| for (i = 0; i < 256; i++) { |
| j = i ? alog8[255 - log8[i]] : 0; |
| j ^= (j << 1) ^ (j << 2) ^ (j << 3) ^ (j << 4); |
| j = (j ^ (j >> 8) ^ 99) & 255; |
| inv_sbox[j] = i; |
| sbox[i] = j; |
| } |
| init_multbl2(dec_multbl, (const int[4]) { 0xe, 0x9, 0xd, 0xb }, |
| log8, alog8, inv_sbox); |
| init_multbl2(enc_multbl, (const int[4]) { 0x2, 0x1, 0x1, 0x3 }, |
| log8, alog8, sbox); |
| } |
| |
| if (key_bits != 128 && key_bits != 192 && key_bits != 256) |
| return AVERROR(EINVAL); |
| |
| a->rounds = rounds; |
| |
| memcpy(tk, key, KC * 4); |
| memcpy(a->round_key[0].u8, key, KC * 4); |
| |
| for (t = KC * 4; t < (rounds + 1) * 16; t += KC * 4) { |
| for (i = 0; i < 4; i++) |
| tk[0][i] ^= sbox[tk[KC - 1][(i + 1) & 3]]; |
| tk[0][0] ^= rcon[rconpointer++]; |
| |
| for (j = 1; j < KC; j++) { |
| if (KC != 8 || j != KC >> 1) |
| for (i = 0; i < 4; i++) |
| tk[j][i] ^= tk[j - 1][i]; |
| else |
| for (i = 0; i < 4; i++) |
| tk[j][i] ^= sbox[tk[j - 1][i]]; |
| } |
| |
| memcpy(a->round_key[0].u8 + t, tk, KC * 4); |
| } |
| |
| if (decrypt) { |
| for (i = 1; i < rounds; i++) { |
| av_aes_block tmp[3]; |
| tmp[2] = a->round_key[i]; |
| subshift(&tmp[1], 0, sbox); |
| mix(tmp, dec_multbl, 1, 3); |
| a->round_key[i] = tmp[0]; |
| } |
| } else { |
| for (i = 0; i < (rounds + 1) >> 1; i++) { |
| FFSWAP(av_aes_block, a->round_key[i], a->round_key[rounds-i]); |
| } |
| } |
| |
| return 0; |
| } |
| |
| #ifdef TEST |
| // LCOV_EXCL_START |
| #include <string.h> |
| #include "lfg.h" |
| #include "log.h" |
| |
| int main(int argc, char **argv) |
| { |
| int i, j; |
| AVAES b; |
| uint8_t rkey[2][16] = { |
| { 0 }, |
| { 0x10, 0xa5, 0x88, 0x69, 0xd7, 0x4b, 0xe5, 0xa3, |
| 0x74, 0xcf, 0x86, 0x7c, 0xfb, 0x47, 0x38, 0x59 } |
| }; |
| uint8_t pt[32], rpt[2][16]= { |
| { 0x6a, 0x84, 0x86, 0x7c, 0xd7, 0x7e, 0x12, 0xad, |
| 0x07, 0xea, 0x1b, 0xe8, 0x95, 0xc5, 0x3f, 0xa3 }, |
| { 0 } |
| }; |
| uint8_t rct[2][16]= { |
| { 0x73, 0x22, 0x81, 0xc0, 0xa0, 0xaa, 0xb8, 0xf7, |
| 0xa5, 0x4a, 0x0c, 0x67, 0xa0, 0xc4, 0x5e, 0xcf }, |
| { 0x6d, 0x25, 0x1e, 0x69, 0x44, 0xb0, 0x51, 0xe0, |
| 0x4e, 0xaa, 0x6f, 0xb4, 0xdb, 0xf7, 0x84, 0x65 } |
| }; |
| uint8_t temp[32]; |
| uint8_t iv[2][16]; |
| int err = 0; |
| |
| av_log_set_level(AV_LOG_DEBUG); |
| |
| for (i = 0; i < 2; i++) { |
| av_aes_init(&b, rkey[i], 128, 1); |
| av_aes_crypt(&b, temp, rct[i], 1, NULL, 1); |
| for (j = 0; j < 16; j++) { |
| if (rpt[i][j] != temp[j]) { |
| av_log(NULL, AV_LOG_ERROR, "%d %02X %02X\n", |
| j, rpt[i][j], temp[j]); |
| err = 1; |
| } |
| } |
| } |
| |
| if (argc > 1 && !strcmp(argv[1], "-t")) { |
| AVAES ae, ad; |
| AVLFG prng; |
| |
| av_aes_init(&ae, (const uint8_t*)"PI=3.141592654..", 128, 0); |
| av_aes_init(&ad, (const uint8_t*)"PI=3.141592654..", 128, 1); |
| av_lfg_init(&prng, 1); |
| |
| for (i = 0; i < 10000; i++) { |
| for (j = 0; j < 32; j++) { |
| pt[j] = av_lfg_get(&prng); |
| } |
| for (j = 0; j < 16; j++) { |
| iv[0][j] = iv[1][j] = av_lfg_get(&prng); |
| } |
| { |
| START_TIMER; |
| av_aes_crypt(&ae, temp, pt, 2, iv[0], 0); |
| if (!(i & (i - 1))) |
| av_log(NULL, AV_LOG_ERROR, "%02X %02X %02X %02X\n", |
| temp[0], temp[5], temp[10], temp[15]); |
| av_aes_crypt(&ad, temp, temp, 2, iv[1], 1); |
| av_aes_crypt(&ae, temp, pt, 2, NULL, 0); |
| if (!(i & (i - 1))) |
| av_log(NULL, AV_LOG_ERROR, "%02X %02X %02X %02X\n", |
| temp[0], temp[5], temp[10], temp[15]); |
| av_aes_crypt(&ad, temp, temp, 2, NULL, 1); |
| STOP_TIMER("aes"); |
| } |
| for (j = 0; j < 16; j++) { |
| if (pt[j] != temp[j]) { |
| av_log(NULL, AV_LOG_ERROR, "%d %d %02X %02X\n", |
| i, j, pt[j], temp[j]); |
| } |
| } |
| } |
| } |
| return err; |
| } |
| // LCOV_EXCL_STOP |
| #endif |
