summaryrefslogtreecommitdiff
path: root/ffmpeg1/libavutil/aes.c
diff options
context:
space:
mode:
authorTim Redfern <tim@eclectronics.org>2013-08-26 15:10:18 +0100
committerTim Redfern <tim@eclectronics.org>2013-08-26 15:10:18 +0100
commit150c9823e71a161e97003849cf8b2f55b21520bd (patch)
tree3559c840cf403d1386708b2591d58f928c7b160d /ffmpeg1/libavutil/aes.c
parentb4b1e2630c95d5e6014463f7608d59dc2322a3b8 (diff)
adding ffmpeg specific version
Diffstat (limited to 'ffmpeg1/libavutil/aes.c')
-rw-r--r--ffmpeg1/libavutil/aes.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/ffmpeg1/libavutil/aes.c b/ffmpeg1/libavutil/aes.c
new file mode 100644
index 0000000..a3eb295
--- /dev/null
+++ b/ffmpeg1/libavutil/aes.c
@@ -0,0 +1,341 @@
+/*
+ * 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
+ * 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
+ */
+
+#include "common.h"
+#include "aes.h"
+#include "intreadwrite.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 {
+ // Note: round_key[16] is accessed in the init code, but this only
+ // overwrites state, which does not matter (see also commit ba554c0).
+ av_aes_block round_key[15];
+ av_aes_block state[2];
+ int rounds;
+} AVAES;
+
+const int av_aes_size= sizeof(AVAES);
+
+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
+};
+
+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
+
+#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)
+{
+ dst->u64[0] = src->u64[0] ^ round_key->u64[0];
+ 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);
+ 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 int mix_core(uint32_t multbl[][256], int a, int b, int c, int d){
+#if CONFIG_SMALL
+ 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(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;
+
+ 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);
+}
+
+void av_aes_crypt(AVAES *a, uint8_t *dst, const uint8_t *src,
+ int count, uint8_t *iv, int decrypt)
+{
+ while (count--) {
+ addkey_s(&a->state[1], src, &a->round_key[a->rounds]);
+ if (decrypt) {
+ crypt(a, 0, inv_sbox, dec_multbl);
+ if (iv) {
+ addkey_s(&a->state[0], iv, &a->state[0]);
+ memcpy(iv, src, 16);
+ }
+ addkey_d(dst, &a->state[0], &a->round_key[0]);
+ } else {
+ if (iv)
+ addkey_s(&a->state[1], iv, &a->state[1]);
+ crypt(a, 2, sbox, enc_multbl);
+ addkey_d(dst, &a->state[0], &a->round_key[0]);
+ if (iv)
+ memcpy(iv, dst, 16);
+ }
+ src += 16;
+ dst += 16;
+ }
+}
+
+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;
+
+ 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
+ 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
+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[FF_ARRAY_ELEMS(enc_multbl)-1][FF_ARRAY_ELEMS(enc_multbl[0])-1]) {
+ 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, (const int[4]) { 0xe, 0x9, 0xd, 0xb },
+ log8, alog8, inv_sbox);
+ init_multbl2(enc_multbl, (const 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);
+ memcpy(a->round_key[0].u8, key, 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++];
+
+ 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]];
+ }
+
+ memcpy(a->round_key[0].u8 + t, tk, KC * 4);
+ }
+
+ if (decrypt) {
+ for (i = 1; i < rounds; i++) {
+ av_aes_block tmp[3];
+ tmp[2] = a->round_key[i];
+ subshift(&tmp[1], 0, sbox);
+ mix(tmp, dec_multbl, 1, 3);
+ a->round_key[i] = tmp[0];
+ }
+ } else {
+ for (i = 0; i < (rounds + 1) >> 1; i++) {
+ FFSWAP(av_aes_block, a->round_key[i], a->round_key[rounds-i]);
+ }
+ }
+
+ return 0;
+}
+
+#ifdef TEST
+// LCOV_EXCL_START
+#include <string.h>
+#include "lfg.h"
+#include "log.h"
+
+int main(int argc, char **argv)
+{
+ int i, j;
+ AVAES 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];
+ int err = 0;
+
+ av_log_set_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]);
+ err = 1;
+ }
+ }
+ }
+
+ if (argc > 1 && !strcmp(argv[1], "-t")) {
+ AVAES ae, ad;
+ AVLFG prng;
+
+ av_aes_init(&ae, "PI=3.141592654..", 128, 0);
+ av_aes_init(&ad, "PI=3.141592654..", 128, 1);
+ av_lfg_init(&prng, 1);
+
+ 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 err;
+}
+// LCOV_EXCL_STOP
+#endif