diff options
Diffstat (limited to 'libavutil/aes.c')
-rw-r--r-- | libavutil/aes.c | 84 |
1 files changed, 44 insertions, 40 deletions
diff --git a/libavutil/aes.c b/libavutil/aes.c index e93fb0565c..397ea77389 100644 --- a/libavutil/aes.c +++ b/libavutil/aes.c @@ -3,42 +3,30 @@ * * some optimization ideas from aes128.c by Reimar Doeffinger * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * 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" -#include "aes.h" -typedef union { - uint64_t u64[2]; - uint32_t u32[4]; - uint8_t u8x4[4][4]; - uint8_t u8[16]; -} av_aes_block; - -typedef struct AVAES { - // Note: round_key[16] is accessed in the init code, but this only - // overwrites state, which does not matter (see also commit ba554c0). - av_aes_block round_key[15]; - av_aes_block state[2]; - int rounds; -} AVAES; +const int av_aes_size= sizeof(AVAES); struct AVAES *av_aes_alloc(void) { @@ -60,9 +48,9 @@ static uint32_t dec_multbl[4][256]; #endif #if HAVE_BIGENDIAN -# define ROT(x, s) ((x >> s) | (x << (32-s))) +# define ROT(x, s) (((x) >> (s)) | ((x) << (32-(s)))) #else -# define ROT(x, s) ((x << s) | (x >> (32-s))) +# define ROT(x, s) (((x) << (s)) | ((x) >> (32-(s)))) #endif static inline void addkey(av_aes_block *dst, const av_aes_block *src, @@ -127,7 +115,7 @@ static inline void mix(av_aes_block state[2], uint32_t multbl[][256], int s1, in state[0].u32[3] = mix_core(multbl, src[3][0], src[s1 - 1][1], src[1][2], src[s3 - 1][3]); } -static inline void crypt(AVAES *a, int s, const uint8_t *sbox, +static inline void aes_crypt(AVAES *a, int s, const uint8_t *sbox, uint32_t multbl[][256]) { int r; @@ -140,31 +128,44 @@ static inline void crypt(AVAES *a, int s, const uint8_t *sbox, subshift(&a->state[0], s, sbox); } -void av_aes_crypt(AVAES *a, uint8_t *dst, const uint8_t *src, - int count, uint8_t *iv, int decrypt) +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[a->rounds]); - if (decrypt) { - 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]); - } else { - if (iv) - addkey_s(&a->state[1], iv, &a->state[1]); - crypt(a, 2, sbox, enc_multbl); - addkey_d(dst, &a->state[0], &a->round_key[0]); - if (iv) - memcpy(iv, dst, 16); + 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) @@ -200,6 +201,8 @@ int av_aes_init(AVAES *a, const uint8_t *key, int key_bits, int decrypt) 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++) { @@ -223,7 +226,7 @@ int av_aes_init(AVAES *a, const uint8_t *key, int key_bits, int decrypt) } if (key_bits != 128 && key_bits != 192 && key_bits != 256) - return -1; + return AVERROR(EINVAL); a->rounds = rounds; @@ -262,3 +265,4 @@ int av_aes_init(AVAES *a, const uint8_t *key, int key_bits, int decrypt) return 0; } + |