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-rw-r--r--contrib/ffmpeg/libavutil/aes.c239
1 files changed, 239 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavutil/aes.c b/contrib/ffmpeg/libavutil/aes.c
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+++ b/contrib/ffmpeg/libavutil/aes.c
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+/*
+ * copyright (c) 2007 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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
+ *
+ * some optimization ideas from aes128.c by Reimar Doeffinger
+ */
+
+#include "common.h"
+#include "aes.h"
+
+typedef struct AVAES{
+ uint8_t round_key[15][4][4];
+ uint8_t state[2][4][4];
+ int rounds;
+}AVAES;
+
+const int av_aes_size= sizeof(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];
+#ifdef 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
+
+static inline void addkey(uint64_t dst[2], uint64_t src[2], uint64_t round_key[2]){
+ dst[0] = src[0] ^ round_key[0];
+ dst[1] = src[1] ^ round_key[1];
+}
+
+static void subshift(uint8_t s0[2][16], int s, uint8_t *box){
+ uint8_t (*s1)[16]= s0[0] - s;
+ uint8_t (*s3)[16]= s0[0] + s;
+ s0[0][0]=box[s0[1][ 0]]; s0[0][ 4]=box[s0[1][ 4]]; s0[0][ 8]=box[s0[1][ 8]]; s0[0][12]=box[s0[1][12]];
+ s1[0][3]=box[s1[1][ 7]]; s1[0][ 7]=box[s1[1][11]]; s1[0][11]=box[s1[1][15]]; s1[0][15]=box[s1[1][ 3]];
+ s0[0][2]=box[s0[1][10]]; s0[0][10]=box[s0[1][ 2]]; s0[0][ 6]=box[s0[1][14]]; s0[0][14]=box[s0[1][ 6]];
+ s3[0][1]=box[s3[1][13]]; s3[0][13]=box[s3[1][ 9]]; s3[0][ 9]=box[s3[1][ 5]]; s3[0][ 5]=box[s3[1][ 1]];
+}
+
+static inline int mix_core(uint32_t multbl[4][256], int a, int b, int c, int d){
+#ifdef CONFIG_SMALL
+#define ROT(x,s) ((x<<s)|(x>>(32-s)))
+ 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(uint8_t state[2][4][4], uint32_t multbl[4][256], int s1, int s3){
+ ((uint32_t *)(state))[0] = mix_core(multbl, state[1][0][0], state[1][s1 ][1], state[1][2][2], state[1][s3 ][3]);
+ ((uint32_t *)(state))[1] = mix_core(multbl, state[1][1][0], state[1][s3-1][1], state[1][3][2], state[1][s1-1][3]);
+ ((uint32_t *)(state))[2] = mix_core(multbl, state[1][2][0], state[1][s3 ][1], state[1][0][2], state[1][s1 ][3]);
+ ((uint32_t *)(state))[3] = mix_core(multbl, state[1][3][0], state[1][s1-1][1], state[1][1][2], state[1][s3-1][3]);
+}
+
+static inline void crypt(AVAES *a, int s, uint8_t *sbox, uint32_t *multbl){
+ 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][0], s, sbox);
+}
+
+void av_aes_crypt(AVAES *a, uint8_t *dst, uint8_t *src, int count, uint8_t *iv, int decrypt){
+ 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+=16;
+ dst+=16;
+ }
+}
+
+static void init_multbl2(uint8_t tbl[1024], int c[4], uint8_t *log8, uint8_t *alog8, 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
+ for(j=256; j<1024; j++)
+ for(i=0; i<4; i++)
+ tbl[4*j+i]= tbl[4*j + ((i-1)&3) - 1024];
+#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];
+
+ if(!enc_multbl[4][1023]){
+ 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[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);
+ }
+
+ if(key_bits!=128 && key_bits!=192 && key_bits!=256)
+ return -1;
+
+ a->rounds= rounds;
+
+ memcpy(tk, key, KC*4);
+
+ for(t= 0; t < (rounds+1)*16;) {
+ memcpy(a->round_key[0][0]+t, tk, KC*4);
+ 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]];
+ }
+ }
+
+ if(decrypt){
+ for(i=1; i<rounds; i++){
+ uint8_t tmp[3][16];
+ memcpy(tmp[2], a->round_key[i][0], 16);
+ subshift(tmp[1], 0, sbox);
+ mix(tmp, dec_multbl, 1, 3);
+ memcpy(a->round_key[i][0], 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]);
+ }
+ }
+
+ return 0;
+}
+
+#ifdef TEST
+#include "log.h"
+
+int main(){
+ int i,j;
+ AVAES ae, ad, 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[16], 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[16];
+
+ av_aes_init(&ae, "PI=3.141592654..", 128, 0);
+ av_aes_init(&ad, "PI=3.141592654..", 128, 1);
+ av_log_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]);
+ }
+
+ for(i=0; i<10000; i++){
+ for(j=0; j<16; j++){
+ pt[j]= random();
+ }
+{START_TIMER
+ av_aes_crypt(&ae, temp, pt, 1, 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, 1, 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 0;
+}
+#endif
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