summaryrefslogtreecommitdiffstats
path: root/libavutil/hmac.c
blob: abbee368b0efa6a5bb1728842f97a6941689e017 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
/*
 * 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 <string.h>

#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 <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[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 */
OpenPOWER on IntegriCloud