/*
* copyright (c) 2007 Michael Niedermayer <michaelni@gmx.at>
*
+ * some optimization ideas from aes128.c by Reimar Doeffinger
+ *
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
*/
#include "common.h"
-#include "log.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 state[4][4];
- uint8_t round_key[15][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;
-static const uint8_t rcon[30] = {
- 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80,
- 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f,
- 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4,
- 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91
+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 log8[256];
-static uint8_t alog8[512];
static uint8_t sbox[256];
static uint8_t inv_sbox[256];
+#if 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(uint32_t state[4], uint32_t round_key[4]){
- int i;
- for(i=0; i<4; i++)
- state[i] ^= round_key[i]; //partial memory stall? FIXME benchmark
+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];
}
-#define SUBSHIFT0(s, box) s[0]=box[s[ 0]]; s[ 4]=box[s[ 4]]; s[ 8]=box[s[ 8]]; s[12]=box[s[12]];
-#define SUBSHIFT1(s, box) t=s[0]; s[0]=box[s[ 4]]; s[ 4]=box[s[ 8]]; s[ 8]=box[s[12]]; s[12]=box[t];
-#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){
- if(a==255) return 0;
- else return alog8[a+b];
+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 void mix(uint8_t state[4][4], int c0, int c1, int c2, int c3){
- uint8_t tmp[4][4];
- int i, j;
+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<<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
+}
- for(i=0; i<16; i++)
- tmp[0][i]= log8[ state[0][i] ];
- for(j=0; j<4; j++)
- for(i=0; i<4; i++)
- state[j][i]= mul( tmp[j][ i ], c0 )
- ^mul( tmp[j][(i+ 1)&3], c1 )
- ^mul( tmp[j][(i+ 2)&3], c2 )
- ^mul( tmp[j][(i+ 3)&3], c3 );
+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, const uint8_t *sbox, uint32_t multbl[][256]){
+ int r;
-void av_aes_decrypt(AVAES *a){
- int t, 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], s, sbox);
+}
- for(r=a->rounds-1; r>=0; r--){
- if(r==a->rounds-1)
- addkey(a->state, a->round_key[r+1]);
- else
- mix(a->state, log8[0xe], log8[0xb], log8[0xd], log8[9]); //FIXME replace log8 by const
- SUBSHIFT0((a->state[0]+0), inv_sbox)
- SUBSHIFT3((a->state[0]+1), inv_sbox)
- SUBSHIFT2((a->state[0]+2), inv_sbox)
- SUBSHIFT1((a->state[0]+3), inv_sbox)
- addkey(a->state, a->round_key[r]);
+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++;
}
}
-void av_aes_encrypt(AVAES *a){
- int r, t;
-
- for(r=0; r<a->rounds; r++){
- addkey(a->state, a->round_key[r]);
- SUBSHIFT0((a->state[0]+0), sbox)
- SUBSHIFT1((a->state[0]+1), sbox)
- SUBSHIFT2((a->state[0]+2), sbox)
- SUBSHIFT3((a->state[0]+3), sbox)
- if(r==a->rounds-1)
- addkey(a->state, a->round_key[r+1]);
- else
- mix(a->state, log8[2], log8[3], 0, 0); //FIXME replace log8 by const / optimze mix as this can be simplified alot
+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]] ];
}
+#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];
+#endif
}
// this is based on the reference AES code by Paulo Barreto and Vincent Rijmen
-AVAES *av_aes_init(uint8_t *key, int keyBits) {
- AVAES *a= av_malloc(sizeof(AVAES));
+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= keyBits/32;
- int ROUNDS= KC + 6;
+ int KC= key_bits>>5;
+ int rounds= KC + 6;
+ uint8_t log8[256];
+ uint8_t alog8[512];
- if(!sbox[255]){
+ 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]=
j^= j+j;
if(j>255) j^= 0x11B;
}
- log8[0]= 255;
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;
-// av_log(NULL, AV_LOG_ERROR, "%d, ", log8[i]);
}
+ 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);
}
- a->rounds= ROUNDS;
+ if(key_bits!=128 && key_bits!=192 && key_bits!=256)
+ return -1;
- if(keyBits!=128 && keyBits!=192 && keyBits!=256)
- return NULL;
+ a->rounds= rounds;
memcpy(tk, key, KC*4);
- for(t= 0; t < (ROUNDS+1)*4; ) {
- for(j = 0; (j < KC) && (t < (ROUNDS+1)*4); j++, t++)
- for(i = 0; i < 4; i++)
- a->round_key[0][t][i] = tk[j][i];
+ 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]];
+ 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/2)
- for(i = 0; i < 4; i++) tk[j][i] ^= tk[j-1][i];
+ 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[KC/2][i] ^= sbox[tk[KC/2 - 1][i]];
+ for(i = 0; i < 4; i++) tk[j][i] ^= sbox[tk[j-1][i]];
+ }
+ }
+
+ if(decrypt){
+ for(i=1; i<rounds; i++){
+ 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].u8[j], a->round_key[rounds-i].u8[j]);
}
}
- return a;
+
+ return 0;
}
#ifdef TEST
+#include "lfg.h"
+#include "log.h"
-int main(){
- int i,j,k;
- AVAES *a= av_aes_init("PI=3.141592654..", 128);
+int main(void){
+ 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];
+ AVLFG prng;
+
+ av_aes_init(&ae, "PI=3.141592654..", 128, 0);
+ av_aes_init(&ad, "PI=3.141592654..", 128, 1);
+ 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);
+ 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] = av_lfg_get(&prng);
+ }
+{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;
}
projects / ffmpeg / blobdiff