/* * Copyright (C) 2012 Martin Storsjo * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include "attributes.h" #include "hmac.h" #include "md5.h" #include "sha.h" #include "mem.h" #define MAX_HASHLEN 32 #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; }; #define DEFINE_SHA(bits) \ static av_cold void sha ## bits ##_init(void *ctx) \ { \ av_sha_init(ctx, bits); \ } DEFINE_SHA(160) DEFINE_SHA(224) DEFINE_SHA(256) 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 = sha160_init; c->update = av_sha_update; c->final = av_sha_final; c->hash = av_sha_alloc(); break; case AV_HMAC_SHA224: c->blocklen = 64; c->hashlen = 28; c->init = sha224_init; c->update = av_sha_update; c->final = av_sha_final; c->hash = av_sha_alloc(); break; case AV_HMAC_SHA256: c->blocklen = 64; c->hashlen = 32; c->init = sha256_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 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[20], key3[131], data3[50]; enum AVHMACType i = AV_HMAC_SHA224; const uint8_t key2[] = "Jefe"; const uint8_t data1[] = "Hi There"; const uint8_t data2[] = "what do ya want for nothing?"; const uint8_t data4[] = "Test Using Larger Than Block-Size Key - Hash Key First"; const uint8_t data5[] = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data"; const uint8_t data6[] = "This is a test using a larger than block-size key and a larger " "than block-size data. The key needs to be hashed before being used" " by the HMAC algorithm."; AVHMAC *hmac = av_hmac_alloc(AV_HMAC_MD5); if (!hmac) return 1; memset(key1, 0x0b, sizeof(key1)); memset(key3, 0xaa, sizeof(key3)); memset(data3, 0xdd, sizeof(data3)); // RFC 2202 test vectors test(hmac, key1, 16, data1, sizeof(data1)); test(hmac, key2, sizeof(key2), data2, sizeof(data2)); test(hmac, key3, 16, data3, sizeof(data3)); test(hmac, key3, 80, data4, sizeof(data4)); test(hmac, key3, 80, data5, sizeof(data5)); av_hmac_free(hmac); /* SHA-1 */ hmac = av_hmac_alloc(AV_HMAC_SHA1); if (!hmac) return 1; // RFC 2202 test vectors test(hmac, key1, sizeof(key1), data1, sizeof(data1)); test(hmac, key2, sizeof(key2), data2, sizeof(data2)); test(hmac, key3, 20, data3, sizeof(data3)); test(hmac, key3, 80, data4, sizeof(data4)); test(hmac, key3, 80, data5, sizeof(data5)); av_hmac_free(hmac); /* SHA-2 */ while (i <= AV_HMAC_SHA256) { hmac = av_hmac_alloc(i); // RFC 4231 test vectors test(hmac, key1, sizeof(key1), data1, sizeof(data1)); test(hmac, key2, sizeof(key2), data2, sizeof(data2)); test(hmac, key3, 20, data3, sizeof(data3)); test(hmac, key3, sizeof(key3), data4, sizeof(data4)); test(hmac, key3, sizeof(key3), data6, sizeof(data6)); av_hmac_free(hmac); i++; } return 0; } #endif /* TEST */