2 * Copyright (C) 2012 Martin Storsjo
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #define MAX_HASHLEN 20
29 #define MAX_BLOCKLEN 64
33 int blocklen, hashlen;
34 void (*final)(void*, uint8_t*);
35 void (*update)(void*, const uint8_t*, int len);
37 uint8_t key[MAX_BLOCKLEN];
41 static void sha1_init(void *ctx)
43 av_sha_init(ctx, 160);
46 AVHMAC *av_hmac_alloc(enum AVHMACType type)
48 AVHMAC *c = av_mallocz(sizeof(*c));
55 c->init = av_md5_init;
56 c->update = av_md5_update;
57 c->final = av_md5_final;
58 c->hash = av_md5_alloc();
64 c->update = av_sha_update;
65 c->final = av_sha_final;
66 c->hash = av_sha_alloc();
79 void av_hmac_free(AVHMAC *c)
87 void av_hmac_init(AVHMAC *c, const uint8_t *key, unsigned int keylen)
90 uint8_t block[MAX_BLOCKLEN];
91 if (keylen > c->blocklen) {
93 c->update(c->hash, key, keylen);
94 c->final(c->hash, c->key);
95 c->keylen = c->hashlen;
97 memcpy(c->key, key, keylen);
101 for (i = 0; i < c->keylen; i++)
102 block[i] = c->key[i] ^ 0x36;
103 for (i = c->keylen; i < c->blocklen; i++)
105 c->update(c->hash, block, c->blocklen);
108 void av_hmac_update(AVHMAC *c, const uint8_t *data, unsigned int len)
110 c->update(c->hash, data, len);
113 int av_hmac_final(AVHMAC *c, uint8_t *out, unsigned int outlen)
115 uint8_t block[MAX_BLOCKLEN];
117 if (outlen < c->hashlen)
118 return AVERROR(EINVAL);
119 c->final(c->hash, out);
121 for (i = 0; i < c->keylen; i++)
122 block[i] = c->key[i] ^ 0x5C;
123 for (i = c->keylen; i < c->blocklen; i++)
125 c->update(c->hash, block, c->blocklen);
126 c->update(c->hash, out, c->hashlen);
127 c->final(c->hash, out);
131 int av_hmac_calc(AVHMAC *c, const uint8_t *data, unsigned int len,
132 const uint8_t *key, unsigned int keylen,
133 uint8_t *out, unsigned int outlen)
135 av_hmac_init(c, key, keylen);
136 av_hmac_update(c, data, len);
137 return av_hmac_final(c, out, outlen);
143 static void test(AVHMAC *hmac, const uint8_t *key, int keylen,
144 const uint8_t *data, int datalen)
146 uint8_t buf[MAX_HASHLEN];
148 // Some of the test vectors are strings, where sizeof() includes the
149 // trailing null byte - remove that.
150 if (!key[keylen - 1])
152 if (!data[datalen - 1])
154 out = av_hmac_calc(hmac, data, datalen, key, keylen, buf, sizeof(buf));
155 for (i = 0; i < out; i++)
156 printf("%02x", buf[i]);
162 uint8_t key1[16], key3[16], data3[50], key4[63], key5[64], key6[65];
163 const uint8_t key2[] = "Jefe";
164 const uint8_t data1[] = "Hi There";
165 const uint8_t data2[] = "what do ya want for nothing?";
166 AVHMAC *hmac = av_hmac_alloc(AV_HMAC_MD5);
169 memset(key1, 0x0b, sizeof(key1));
170 memset(key3, 0xaa, sizeof(key3));
171 memset(key4, 0x44, sizeof(key4));
172 memset(key5, 0x55, sizeof(key5));
173 memset(key6, 0x66, sizeof(key6));
174 memset(data3, 0xdd, sizeof(data3));
175 // RFC 2104 test vectors
176 test(hmac, key1, sizeof(key1), data1, sizeof(data1));
177 test(hmac, key2, sizeof(key2), data2, sizeof(data2));
178 test(hmac, key3, sizeof(key3), data3, sizeof(data3));
179 // Additional tests, to test cases where the key is too long
180 test(hmac, key4, sizeof(key4), data1, sizeof(data1));
181 test(hmac, key5, sizeof(key5), data2, sizeof(data2));
182 test(hmac, key6, sizeof(key6), data3, sizeof(data3));