X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavutil%2Faes.c;h=3ba5e9aef4501960b6489905314402d66ae53805;hb=cde7df25ef74b85b5ce11d9171779f28f0c12d15;hp=fc6c4168cd7d8c678439ea71c025ed22f9ee6f39;hpb=4bfe0644606264c2c81ccc8b044ca46e52e7b24a;p=ffmpeg diff --git a/libavutil/aes.c b/libavutil/aes.c index fc6c4168cd7..3ba5e9aef45 100644 --- a/libavutil/aes.c +++ b/libavutil/aes.c @@ -22,6 +22,8 @@ #include "common.h" #include "aes.h" +#include "intreadwrite.h" +#include "timer.h" typedef union { uint64_t u64[2]; @@ -32,13 +34,20 @@ typedef union { typedef struct AVAES { // Note: round_key[16] is accessed in the init code, but this only - // overwrites state, which does not matter (see also r7471). + // overwrites state, which does not matter (see also commit ba554c0). av_aes_block round_key[15]; av_aes_block state[2]; int rounds; } AVAES; +#if FF_API_CONTEXT_SIZE const int av_aes_size= sizeof(AVAES); +#endif + +struct AVAES *av_aes_alloc(void) +{ + return av_mallocz(sizeof(struct AVAES)); +} static const uint8_t rcon[10] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 @@ -54,6 +63,12 @@ static uint32_t enc_multbl[4][256]; static uint32_t dec_multbl[4][256]; #endif +#if HAVE_BIGENDIAN +# define ROT(x, s) ((x >> s) | (x << (32-s))) +#else +# define ROT(x, s) ((x << s) | (x >> (32-s))) +#endif + static inline void addkey(av_aes_block *dst, const av_aes_block *src, const av_aes_block *round_key) { @@ -61,6 +76,20 @@ static inline void addkey(av_aes_block *dst, const av_aes_block *src, dst->u64[1] = src->u64[1] ^ round_key->u64[1]; } +static inline void addkey_s(av_aes_block *dst, const uint8_t *src, + const av_aes_block *round_key) +{ + dst->u64[0] = AV_RN64(src) ^ round_key->u64[0]; + dst->u64[1] = AV_RN64(src + 8) ^ round_key->u64[1]; +} + +static inline void addkey_d(uint8_t *dst, const av_aes_block *src, + const av_aes_block *round_key) +{ + AV_WN64(dst, src->u64[0] ^ round_key->u64[0]); + AV_WN64(dst + 8, src->u64[1] ^ round_key->u64[1]); +} + 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); @@ -86,7 +115,6 @@ static void subshift(av_aes_block s0[2], int s, const uint8_t *box) 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))) 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]; @@ -114,51 +142,54 @@ static inline void crypt(AVAES *a, int s, const uint8_t *sbox, subshift(&a->state[0], s, sbox); } -void av_aes_crypt(AVAES *a, uint8_t *dst_, const uint8_t *src_, - int count, uint8_t *iv_, int decrypt) +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]); + addkey_s(&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); + addkey_s(&a->state[0], iv, &a->state[0]); memcpy(iv, src, 16); } - addkey(dst, &a->state[0], &a->round_key[0]); + addkey_d(dst, &a->state[0], &a->round_key[0]); } else { if (iv) - addkey(&a->state[1], &a->state[1], iv); + addkey_s(&a->state[1], iv, &a->state[1]); crypt(a, 2, sbox, enc_multbl); - addkey(dst, &a->state[0], &a->round_key[0]); + addkey_d(dst, &a->state[0], &a->round_key[0]); if (iv) memcpy(iv, dst, 16); } - src++; - dst++; + src += 16; + dst += 16; } } -static void init_multbl2(uint8_t tbl[1024], const int c[4], +static void init_multbl2(uint32_t tbl[][256], 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]]]; - } + int i; + + for (i = 0; i < 256; i++) { + int x = sbox[i]; + if (x) { + int k, l, m, n; + x = log8[x]; + k = alog8[x + log8[c[0]]]; + l = alog8[x + log8[c[1]]]; + m = alog8[x + log8[c[2]]]; + n = alog8[x + log8[c[3]]]; + tbl[0][i] = AV_NE(MKBETAG(k,l,m,n), MKTAG(k,l,m,n)); #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]; + tbl[1][i] = ROT(tbl[0][i], 8); + tbl[2][i] = ROT(tbl[0][i], 16); + tbl[3][i] = ROT(tbl[0][i], 24); #endif + } + } } // this is based on the reference AES code by Paulo Barreto and Vincent Rijmen @@ -187,9 +218,9 @@ int av_aes_init(AVAES *a, const uint8_t *key, int key_bits, int decrypt) inv_sbox[j] = i; sbox[i] = j; } - init_multbl2(dec_multbl[0], (const int[4]) { 0xe, 0x9, 0xd, 0xb }, + init_multbl2(dec_multbl, (const int[4]) { 0xe, 0x9, 0xd, 0xb }, log8, alog8, inv_sbox); - init_multbl2(enc_multbl[0], (const int[4]) { 0x2, 0x1, 0x1, 0x3 }, + init_multbl2(enc_multbl, (const int[4]) { 0x2, 0x1, 0x1, 0x3 }, log8, alog8, sbox); } @@ -199,11 +230,9 @@ int av_aes_init(AVAES *a, const uint8_t *key, int key_bits, int decrypt) a->rounds = rounds; memcpy(tk, key, KC * 4); + memcpy(a->round_key[0].u8, key, KC * 4); - for (t = 0; t < (rounds + 1) * 16;) { - memcpy(a->round_key[0].u8 + t, tk, KC * 4); - t += KC * 4; - + for (t = KC * 4; t < (rounds + 1) * 16; t += KC * 4) { for (i = 0; i < 4; i++) tk[0][i] ^= sbox[tk[KC - 1][(i + 1) & 3]]; tk[0][0] ^= rcon[rconpointer++]; @@ -216,20 +245,21 @@ int av_aes_init(AVAES *a, const uint8_t *key, int key_bits, int decrypt) for (i = 0; i < 4; i++) tk[j][i] ^= sbox[tk[j - 1][i]]; } + + memcpy(a->round_key[0].u8 + t, tk, KC * 4); } if (decrypt) { for (i = 1; i < rounds; i++) { av_aes_block tmp[3]; - memcpy(&tmp[2], &a->round_key[i], 16); + tmp[2] = a->round_key[i]; subshift(&tmp[1], 0, sbox); mix(tmp, dec_multbl, 1, 3); - memcpy(&a->round_key[i], &tmp[0], 16); + a->round_key[i] = tmp[0]; } } 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]); + FFSWAP(av_aes_block, a->round_key[i], a->round_key[rounds-i]); } }