diff options
Diffstat (limited to 'ffmpeg/libavutil/hmac.c')
| -rw-r--r-- | ffmpeg/libavutil/hmac.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/ffmpeg/libavutil/hmac.c b/ffmpeg/libavutil/hmac.c new file mode 100644 index 0000000..e5f1434 --- /dev/null +++ b/ffmpeg/libavutil/hmac.c @@ -0,0 +1,186 @@ +/* + * Copyright (C) 2012 Martin Storsjo + * + * 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 <string.h> + +#include "hmac.h" +#include "md5.h" +#include "sha.h" +#include "mem.h" + +#define MAX_HASHLEN 20 +#define MAX_BLOCKLEN 64 + +struct AVHMAC { + void *hash; + int blocklen, hashlen; + void (*final)(void*, uint8_t*); + void (*update)(void*, const uint8_t*, int len); + void (*init)(void*); + uint8_t key[MAX_BLOCKLEN]; + int keylen; +}; + +static void sha1_init(void *ctx) +{ + av_sha_init(ctx, 160); +} + +AVHMAC *av_hmac_alloc(enum AVHMACType type) +{ + AVHMAC *c = av_mallocz(sizeof(*c)); + if (!c) + return NULL; + switch (type) { + case AV_HMAC_MD5: + c->blocklen = 64; + c->hashlen = 16; + c->init = av_md5_init; + c->update = av_md5_update; + c->final = av_md5_final; + c->hash = av_md5_alloc(); + break; + case AV_HMAC_SHA1: + c->blocklen = 64; + c->hashlen = 20; + c->init = sha1_init; + c->update = av_sha_update; + c->final = av_sha_final; + c->hash = av_sha_alloc(); + break; + default: + av_free(c); + return NULL; + } + if (!c->hash) { + av_free(c); + return NULL; + } + return c; +} + +void av_hmac_free(AVHMAC *c) +{ + if (!c) + return; + av_free(c->hash); + av_free(c); +} + +void av_hmac_init(AVHMAC *c, const uint8_t *key, unsigned int keylen) +{ + int i; + uint8_t block[MAX_BLOCKLEN]; + if (keylen > c->blocklen) { + c->init(c->hash); + c->update(c->hash, key, keylen); + c->final(c->hash, c->key); + c->keylen = c->hashlen; + } else { + memcpy(c->key, key, keylen); + c->keylen = keylen; + } + c->init(c->hash); + for (i = 0; i < c->keylen; i++) + block[i] = c->key[i] ^ 0x36; + for (i = c->keylen; i < c->blocklen; i++) + block[i] = 0x36; + c->update(c->hash, block, c->blocklen); +} + +void av_hmac_update(AVHMAC *c, const uint8_t *data, unsigned int len) +{ + c->update(c->hash, data, len); +} + +int av_hmac_final(AVHMAC *c, uint8_t *out, unsigned int outlen) +{ + uint8_t block[MAX_BLOCKLEN]; + int i; + if (outlen < c->hashlen) + return AVERROR(EINVAL); + c->final(c->hash, out); + c->init(c->hash); + for (i = 0; i < c->keylen; i++) + block[i] = c->key[i] ^ 0x5C; + for (i = c->keylen; i < c->blocklen; i++) + block[i] = 0x5C; + c->update(c->hash, block, c->blocklen); + c->update(c->hash, out, c->hashlen); + c->final(c->hash, out); + return c->hashlen; +} + +int av_hmac_calc(AVHMAC *c, const uint8_t *data, unsigned int len, + const uint8_t *key, unsigned int keylen, + uint8_t *out, unsigned int outlen) +{ + av_hmac_init(c, key, keylen); + av_hmac_update(c, data, len); + return av_hmac_final(c, out, outlen); +} + +#ifdef TEST +#include <stdio.h> + +static void test(AVHMAC *hmac, const uint8_t *key, int keylen, + const uint8_t *data, int datalen) +{ + uint8_t buf[MAX_HASHLEN]; + int out, i; + // Some of the test vectors are strings, where sizeof() includes the + // trailing null byte - remove that. + if (!key[keylen - 1]) + keylen--; + if (!data[datalen - 1]) + datalen--; + out = av_hmac_calc(hmac, data, datalen, key, keylen, buf, sizeof(buf)); + for (i = 0; i < out; i++) + printf("%02x", buf[i]); + printf("\n"); +} + +int main(void) +{ + uint8_t key1[16], key3[16], data3[50], key4[63], key5[64], key6[65]; + const uint8_t key2[] = "Jefe"; + const uint8_t data1[] = "Hi There"; + const uint8_t data2[] = "what do ya want for nothing?"; + AVHMAC *hmac = av_hmac_alloc(AV_HMAC_MD5); + if (!hmac) + return 1; + memset(key1, 0x0b, sizeof(key1)); + memset(key3, 0xaa, sizeof(key3)); + memset(key4, 0x44, sizeof(key4)); + memset(key5, 0x55, sizeof(key5)); + memset(key6, 0x66, sizeof(key6)); + memset(data3, 0xdd, sizeof(data3)); + // RFC 2104 test vectors + test(hmac, key1, sizeof(key1), data1, sizeof(data1)); + test(hmac, key2, sizeof(key2), data2, sizeof(data2)); + test(hmac, key3, sizeof(key3), data3, sizeof(data3)); + // Additional tests, to test cases where the key is too long + test(hmac, key4, sizeof(key4), data1, sizeof(data1)); + test(hmac, key5, sizeof(key5), data2, sizeof(data2)); + test(hmac, key6, sizeof(key6), data3, sizeof(data3)); + av_hmac_free(hmac); + return 0; +} +#endif /* TEST */ |