X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavutil%2Faes.c;h=346676bae33faecb2ad40770d8f581bef1b09256;hb=812f2376eecc19c40a95ade1f7a43b762106e0f7;hp=fa07bc83e630575caccbf6582695ece4b0afb47c;hpb=cc6b4da83aa2bdbb627bb43b3a746fd44add8eba;p=ffmpeg diff --git a/libavutil/aes.c b/libavutil/aes.c index fa07bc83e63..346676bae33 100644 --- a/libavutil/aes.c +++ b/libavutil/aes.c @@ -1,31 +1,40 @@ /* * copyright (c) 2007 Michael Niedermayer * - * This file is part of FFmpeg. + * some optimization ideas from aes128.c by Reimar Doeffinger + * + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav 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, + * Libav 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 + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - * - * some optimization ideas from aes128.c by Reimar Doeffinger */ #include "common.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{ - uint8_t round_key[15][4][4]; - uint8_t state[4][4]; + // Note: round_key[16] is accessed in the init code, but this only + // overwrites state, which does not matter (see also r7471). + av_aes_block round_key[15]; + av_aes_block state[2]; int rounds; }AVAES; @@ -37,7 +46,7 @@ static const uint8_t rcon[10] = { static uint8_t sbox[256]; static uint8_t inv_sbox[256]; -#ifdef CONFIG_SMALL +#if CONFIG_SMALL static uint32_t enc_multbl[1][256]; static uint32_t dec_multbl[1][256]; #else @@ -45,76 +54,78 @@ static uint32_t enc_multbl[4][256]; static uint32_t dec_multbl[4][256]; #endif -static inline void addkey(uint64_t state[2], uint64_t round_key[2]){ - state[0] ^= round_key[0]; - state[1] ^= round_key[1]; +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 void subshift(uint8_t s0[4], uint8_t s1[4], uint8_t s3[4], uint8_t *box){ - int t; - s0[0]=box[s0[ 0]]; s0[ 4]=box[s0[ 4]]; s0[ 8]=box[s0[ 8]]; s0[12]=box[s0[12]]; - t=s1[0]; s1[0]=box[s1[ 4]]; s1[ 4]=box[s1[ 8]]; s1[ 8]=box[s1[12]]; s1[12]=box[t]; - t=s0[2]; s0[2]=box[s0[10]]; s0[10]=box[ t]; t=s0[ 6]; s0[ 6]=box[s0[14]]; s0[14]=box[t]; - t=s3[0]; s3[0]=box[s3[12]]; s3[12]=box[s3[ 8]]; s3[ 8]=box[s3[ 4]]; s3[ 4]=box[t]; +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 #define ROT(x,s) ((x<>(32-s))) -#if 0 -static inline void mix(uint8_t state[4][4], uint32_t multbl[4][256]){ - int i; - for(i=0; i<4; i++) -#ifdef CONFIG_SMALL - ((uint32_t *)(state))[i] = multbl[0][state[i][0]] ^ ROT(multbl[0][state[i][1]], 8) - ^ROT(multbl[0][state[i][2]],16) ^ ROT(multbl[0][state[i][3]],24); + return multbl[0][a] ^ ROT(multbl[0][b], 8) ^ ROT(multbl[0][c], 16) ^ ROT(multbl[0][d], 24); #else - ((uint32_t *)(state))[i] = multbl[0][state[i][0]] ^ multbl[1][state[i][1]] - ^multbl[2][state[i][2]] ^ multbl[3][state[i][3]]; + return multbl[0][a] ^ multbl[1][b] ^ multbl[2][c] ^ multbl[3][d]; #endif } -#endif -static inline void mix2(uint8_t state[4][4], uint32_t multbl[4][256], int s1, int s3){ - int a = multbl[0][state[0][0]] ^ multbl[1][state[s1 ][1]] - ^multbl[2][state[2][2]] ^ multbl[3][state[s3 ][3]]; - int b = multbl[0][state[1][0]] ^ multbl[1][state[s3-1][1]] - ^multbl[2][state[3][2]] ^ multbl[3][state[s1-1][3]]; - int c = multbl[0][state[2][0]] ^ multbl[1][state[s3 ][1]] - ^multbl[2][state[0][2]] ^ multbl[3][state[s1 ][3]]; - int d = multbl[0][state[3][0]] ^ multbl[1][state[s1-1][1]] - ^multbl[2][state[1][2]] ^ multbl[3][state[s3-1][3]]; - - ((uint32_t *)(state))[0]=a; - ((uint32_t *)(state))[1]=b; - ((uint32_t *)(state))[2]=c; - ((uint32_t *)(state))[3]=d; + +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 crypt(AVAES *a, int s, uint8_t *sbox, uint32_t *multbl){ +static inline void crypt(AVAES *a, int s, const uint8_t *sbox, uint32_t multbl[][256]){ int r; - for(r=a->rounds; r>1; r--){ - addkey(a->state, a->round_key[r]); - mix2(a->state, multbl, 3-s, 1+s); + 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]); } - addkey(a->state, a->round_key[1]); - subshift(a->state[0], a->state[0]+3-s, a->state[0]+1+s, sbox); - addkey(a->state, a->round_key[0]); -} - -static void aes_decrypt(AVAES *a){ - crypt(a, 0, inv_sbox, dec_multbl); + subshift(&a->state[0], s, sbox); } -static void aes_encrypt(AVAES *a){ - crypt(a, 2, sbox, enc_multbl); +void av_aes_crypt(AVAES *a, uint8_t *dst_, const uint8_t *src_, int count, uint8_t *iv_, int decrypt){ + av_aes_block *dst = (av_aes_block *)dst_; + const av_aes_block *src = (const av_aes_block *)src_; + av_aes_block *iv = (av_aes_block *)iv_; + while(count--){ + addkey(&a->state[1], src, &a->round_key[a->rounds]); + if(decrypt) { + crypt(a, 0, inv_sbox, dec_multbl); + if(iv){ + addkey(&a->state[0], &a->state[0], iv); + memcpy(iv, src, 16); + } + addkey(dst, &a->state[0], &a->round_key[0]); + }else{ + if(iv) addkey(&a->state[1], &a->state[1], iv); + crypt(a, 2, sbox, enc_multbl); + addkey(dst, &a->state[0], &a->round_key[0]); + if(iv) memcpy(iv, dst, 16); + } + src++; + dst++; + } } -static void init_multbl2(uint8_t tbl[1024], int c[4], uint8_t *log8, uint8_t *alog8, uint8_t *sbox){ +static void init_multbl2(uint8_t tbl[1024], const int c[4], const uint8_t *log8, const uint8_t *alog8, const uint8_t *sbox){ int i, j; for(i=0; i<1024; i++){ int x= sbox[i>>2]; if(x) tbl[i]= alog8[ log8[x] + log8[c[i&3]] ]; } -#ifndef CONFIG_SMALL +#if !CONFIG_SMALL for(j=256; j<1024; j++) for(i=0; i<4; i++) tbl[4*j+i]= tbl[4*j + ((i-1)&3) - 1024]; @@ -122,7 +133,7 @@ static void init_multbl2(uint8_t tbl[1024], int c[4], uint8_t *log8, uint8_t *al } // this is based on the reference AES code by Paulo Barreto and Vincent Rijmen -int av_aes_init(AVAES *a, uint8_t *key, int key_bits, int decrypt) { +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; @@ -130,7 +141,7 @@ int av_aes_init(AVAES *a, uint8_t *key, int key_bits, int decrypt) { uint8_t log8[256]; uint8_t alog8[512]; - if(!enc_multbl[4][1023]){ + 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]= @@ -146,8 +157,8 @@ int av_aes_init(AVAES *a, uint8_t *key, int key_bits, int decrypt) { inv_sbox[j]= i; sbox [i]= j; } - init_multbl2(dec_multbl[0], (int[4]){0xe, 0x9, 0xd, 0xb}, log8, alog8, inv_sbox); - init_multbl2(enc_multbl[0], (int[4]){0x2, 0x1, 0x1, 0x3}, log8, alog8, sbox); + init_multbl2(dec_multbl[0], (const int[4]){0xe, 0x9, 0xd, 0xb}, log8, alog8, inv_sbox); + init_multbl2(enc_multbl[0], (const int[4]){0x2, 0x1, 0x1, 0x3}, log8, alog8, sbox); } if(key_bits!=128 && key_bits!=192 && key_bits!=256) @@ -157,9 +168,9 @@ int av_aes_init(AVAES *a, uint8_t *key, int key_bits, int decrypt) { memcpy(tk, key, KC*4); - for(t= 0; t < (rounds+1)*4;) { - memcpy(a->round_key[0][t], tk, KC*4); - t+= KC; + for(t= 0; t < (rounds+1)*16;) { + memcpy(a->round_key[0].u8+t, tk, KC*4); + t+= KC*4; for(i = 0; i < 4; i++) tk[0][i] ^= sbox[tk[KC-1][(i+1)&3]]; @@ -175,13 +186,16 @@ int av_aes_init(AVAES *a, uint8_t *key, int key_bits, int decrypt) { if(decrypt){ for(i=1; iround_key[i][0], a->round_key[i][0]+3, a->round_key[i][0]+1, sbox); - mix2(a->round_key[i], dec_multbl, 1, 3); + av_aes_block tmp[3]; + memcpy(&tmp[2], &a->round_key[i], 16); + subshift(&tmp[1], 0, sbox); + mix(tmp, dec_multbl, 1, 3); + memcpy(&a->round_key[i], &tmp[0], 16); } }else{ for(i=0; i<(rounds+1)>>1; i++){ for(j=0; j<16; j++) - FFSWAP(int, a->round_key[i][0][j], a->round_key[rounds-i][0][j]); + FFSWAP(int, a->round_key[i].u8[j], a->round_key[rounds-i].u8[j]); } } @@ -189,9 +203,10 @@ int av_aes_init(AVAES *a, uint8_t *key, int key_bits, int decrypt) { } #ifdef TEST +#include "lfg.h" #include "log.h" -int main(){ +int main(void){ int i,j; AVAES ae, ad, b; uint8_t rkey[2][16]= { @@ -203,35 +218,35 @@ int main(){ 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[16]; + AVLFG prng; av_aes_init(&ae, "PI=3.141592654..", 128, 0); av_aes_init(&ad, "PI=3.141592654..", 128, 1); - av_log_level= AV_LOG_DEBUG; + av_log_set_level(AV_LOG_DEBUG); + av_lfg_init(&prng, 1); for(i=0; i<2; i++){ av_aes_init(&b, rkey[i], 128, 1); - memcpy(b.state, rct[i], 16); - aes_decrypt(&b); + av_aes_crypt(&b, temp, rct[i], 1, NULL, 1); for(j=0; j<16; j++) - if(rpt[i][j] != b.state[0][j]) - av_log(NULL, AV_LOG_ERROR, "%d %02X %02X\n", j, rpt[i][j], b.state[0][j]); + if(rpt[i][j] != temp[j]) + av_log(NULL, AV_LOG_ERROR, "%d %02X %02X\n", j, rpt[i][j], temp[j]); } for(i=0; i<10000; i++){ for(j=0; j<16; j++){ - pt[j]= random(); + pt[j] = av_lfg_get(&prng); } - memcpy(ae.state, pt, 16); {START_TIMER - aes_encrypt(&ae); + av_aes_crypt(&ae, temp, pt, 1, NULL, 0); if(!(i&(i-1))) - av_log(NULL, AV_LOG_ERROR, "%02X %02X %02X %02X\n", ae.state[0][0], ae.state[1][1], ae.state[2][2], ae.state[3][3]); - memcpy(ad.state, ae.state, 16); - aes_decrypt(&ad); + 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, 1, NULL, 1); STOP_TIMER("aes")} for(j=0; j<16; j++){ - if(pt[j] != ad.state[0][j]){ - av_log(NULL, AV_LOG_ERROR, "%d %d %02X %02X\n", i,j, pt[j], ad.state[0][j]); + if(pt[j] != temp[j]){ + av_log(NULL, AV_LOG_ERROR, "%d %d %02X %02X\n", i,j, pt[j], temp[j]); } } }