videolan
/
ffmpeg
mirror of https://git.videolan.org/git/ffmpeg.git
1
Fork 0
Code Releases Activity

init multbl 

code can now decrypt its own encryption correctly
can anyone provide me with a correct test AES key + cyphertext + plaintext?

Originally committed as revision 7479 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2007-01-14 16:43:32 +00:00
parent b58ecac647
commit ff8f659429
1 changed files with 28 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
libavutil/aes.c
View File

@ -52,11 +52,6 @@ static inline void addkey(uint64_t state[2], uint64_t round_key[2]){
#define SUBSHIFT2(s, box) t=s[0]; s[0]=box[s[ 8]]; s[ 8]=box[ t]; t=s[ 4]; s[ 4]=box[s[12]]; s[12]=box[t];
#define SUBSHIFT3(s, box) t=s[0]; s[0]=box[s[12]]; s[12]=box[s[ 8]]; s[ 8]=box[s[ 4]]; s[ 4]=box[t];
static inline int mul(int a, int b, uint8_t alog8[256]){
if(a==255) return 0;
else return alog8[a+b];
}
#define ROT(x,s) ((x>>s)|(x<<(32-s))
static inline void mix(uint8_t state[4][4], uint32_t multbl[4][256]){
@ -104,6 +99,12 @@ void av_aes_encrypt(AVAES *a){
}
}
static init_multbl(uint8_t tbl[256], int c[4], uint8_t *log8, uint8_t *alog8){
int i;
for(i=4; i<1024; i++)
tbl[i]= alog8[ log8[i/4] + log8[c[i&3]] ];
}
// this is based on the reference AES code by Paulo Barreto and Vincent Rijmen
AVAES *av_aes_init(uint8_t *key, int key_bits) {
AVAES *a;
@ -131,8 +132,15 @@ AVAES *av_aes_init(uint8_t *key, int key_bits) {
inv_sbox[j]= i;
sbox [i]= j;
// av_log(NULL, AV_LOG_ERROR, "%d, ", log8[i]);
//FIXME multbl init
}
init_multbl(dec_multbl[0], (int[4]){0xe, 0x9, 0xd, 0xb}, log8, alog8);
init_multbl(dec_multbl[1], (int[4]){0xb, 0xe, 0x9, 0xd}, log8, alog8);
init_multbl(dec_multbl[2], (int[4]){0xd, 0xb, 0xe, 0x9}, log8, alog8);
init_multbl(dec_multbl[3], (int[4]){0x9, 0xd, 0xb, 0xe}, log8, alog8);
init_multbl(enc_multbl[0], (int[4]){0x2, 0x1, 0x1, 0x3}, log8, alog8);
init_multbl(enc_multbl[1], (int[4]){0x3, 0x2, 0x1, 0x1}, log8, alog8);
init_multbl(enc_multbl[2], (int[4]){0x1, 0x3, 0x2, 0x1}, log8, alog8);
init_multbl(enc_multbl[3], (int[4]){0x1, 0x1, 0x3, 0x2}, log8, alog8);
}
if(key_bits!=128 && key_bits!=192 && key_bits!=256)
@ -166,8 +174,22 @@ AVAES *av_aes_init(uint8_t *key, int key_bits) {
int main(){
int i,j,k;
AVAES *a= av_aes_init("PI=3.141592654..", 128);
uint8_t ct[16], pt[16], key[32];
for(i=0; i<10000; i++){
for(j=0; j<16; j++){
pt[j]= random();
}
memcpy(a->state, pt, 16);
av_aes_encrypt(a);
if(!(i&(i-1)))
av_log(NULL, AV_LOG_ERROR, "%02X %02X %02X %02X\n", a->state[0][0], a->state[1][1], a->state[2][2], a->state[3][3]);
av_aes_decrypt(a);
for(j=0; j<16; j++){
if(pt[j] != a->state[0][j]){
av_log(NULL, AV_LOG_ERROR, "%d %d %02X %02X\n", i,j, pt[j], a->state[0][j]);
}
}
}
return 0;
}