videolan/ffmpeg
1
Fork 0
mirror of https://git.videolan.org/git/ffmpeg.git synced 2024-09-07 16:40:10 +02:00
Code Releases Activity

cbc support

Browse Source 
Originally committed as revision 7550 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2007-01-16 19:08:52 +00:00
parent 2d3475ae6a
commit 97e3458c46
1 changed files with 23 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
libavutil/aes.c
View File

@ -85,24 +85,35 @@ static inline void mix(uint8_t state[2][4][4], uint32_t multbl[4][256], int s1,
^multbl[2][state[1][1][2]] ^ multbl[3][state[1][s3-1][3]];
}
static inline void crypt(AVAES *a, int s, uint8_t *sbox, uint32_t *multbl, uint8_t *dst, uint8_t *src){
static inline void crypt(AVAES *a, int s, uint8_t *sbox, uint32_t *multbl){
int r;
addkey(a->state[1], src, a->round_key[a->rounds]);
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);
addkey(dst, a->state[0], a->round_key[0]);
}
static void aes_decrypt(AVAES *a, uint8_t *dst, uint8_t *src){
crypt(a, 0, inv_sbox, dec_multbl, dst, src);
}
static void aes_encrypt(AVAES *a, uint8_t *dst, uint8_t *src){
crypt(a, 2, sbox, enc_multbl, dst, src);
void 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){
@ -211,7 +222,7 @@ int main(){
for(i=0; i<2; i++){
av_aes_init(&b, rkey[i], 128, 1);
aes_decrypt(&b, temp, rct[i]);
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]);
@ -222,10 +233,10 @@ int main(){
pt[j]= random();
}
{START_TIMER
aes_encrypt(&ae, temp, pt);
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]);
aes_decrypt(&ad, temp, temp);
aes_crypt(&ad, temp, temp, 1, NULL, 1);
STOP_TIMER("aes")}
for(j=0; j<16; j++){
if(pt[j] != temp[j]){