1 /*
2 * Copyright (C) 2012 Martin Storsjo
3 *
4 * This file is part of FFmpeg.
5 *
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.
10 *
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.
15 *
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
19 */
20
21 #include <stddef.h>
22 #include <stdint.h>
23 #include <string.h>
24
25 #include "attributes.h"
26 #include "hmac.h"
27 #include "md5.h"
28 #include "sha.h"
29 #include "sha512.h"
30 #include "mem.h"
31 #include "version.h"
32
33 #define MAX_HASHLEN 64
34 #define MAX_BLOCKLEN 128
35
36 typedef void (*hmac_final)(void *ctx, uint8_t *dst);
37 #if FF_API_CRYPTO_SIZE_T
38 typedef void (*hmac_update)(void *ctx, const uint8_t *src, int len);
39 #else
40 typedef void (*hmac_update)(void *ctx, const uint8_t *src, size_t len);
41 #endif
42 typedef void (*hmac_init)(void *ctx);
43
44 struct AVHMAC {
45 void *hash;
46 int blocklen, hashlen;
47 hmac_final final;
48 hmac_update update;
49 hmac_init init;
50 uint8_t key[MAX_BLOCKLEN];
51 int keylen;
52 };
53
54 #define DEFINE_SHA(bits) \
55 static av_cold void sha ## bits ##_init(void *ctx) \
56 { \
57 av_sha_init(ctx, bits); \
58 }
59
60 #define DEFINE_SHA512(bits) \
61 static av_cold void sha ## bits ##_init(void *ctx) \
62 { \
63 av_sha512_init(ctx, bits); \
64 }
65
66 DEFINE_SHA(160)
67 DEFINE_SHA(224)
68 DEFINE_SHA(256)
69 DEFINE_SHA512(384)
70 DEFINE_SHA512(512)
71
av_hmac_alloc(enum AVHMACType type)72 AVHMAC *av_hmac_alloc(enum AVHMACType type)
73 {
74 AVHMAC *c = av_mallocz(sizeof(*c));
75 if (!c)
76 return NULL;
77 switch (type) {
78 case AV_HMAC_MD5:
79 c->blocklen = 64;
80 c->hashlen = 16;
81 c->init = (hmac_init) av_md5_init;
82 c->update = (hmac_update) av_md5_update;
83 c->final = (hmac_final) av_md5_final;
84 c->hash = av_md5_alloc();
85 break;
86 case AV_HMAC_SHA1:
87 c->blocklen = 64;
88 c->hashlen = 20;
89 c->init = sha160_init;
90 c->update = (hmac_update) av_sha_update;
91 c->final = (hmac_final) av_sha_final;
92 c->hash = av_sha_alloc();
93 break;
94 case AV_HMAC_SHA224:
95 c->blocklen = 64;
96 c->hashlen = 28;
97 c->init = sha224_init;
98 c->update = (hmac_update) av_sha_update;
99 c->final = (hmac_final) av_sha_final;
100 c->hash = av_sha_alloc();
101 break;
102 case AV_HMAC_SHA256:
103 c->blocklen = 64;
104 c->hashlen = 32;
105 c->init = sha256_init;
106 c->update = (hmac_update) av_sha_update;
107 c->final = (hmac_final) av_sha_final;
108 c->hash = av_sha_alloc();
109 break;
110 case AV_HMAC_SHA384:
111 c->blocklen = 128;
112 c->hashlen = 48;
113 c->init = sha384_init;
114 c->update = (hmac_update) av_sha512_update;
115 c->final = (hmac_final) av_sha512_final;
116 c->hash = av_sha512_alloc();
117 break;
118 case AV_HMAC_SHA512:
119 c->blocklen = 128;
120 c->hashlen = 64;
121 c->init = sha512_init;
122 c->update = (hmac_update) av_sha512_update;
123 c->final = (hmac_final) av_sha512_final;
124 c->hash = av_sha512_alloc();
125 break;
126 default:
127 av_free(c);
128 return NULL;
129 }
130 if (!c->hash) {
131 av_free(c);
132 return NULL;
133 }
134 return c;
135 }
136
av_hmac_free(AVHMAC * c)137 void av_hmac_free(AVHMAC *c)
138 {
139 if (!c)
140 return;
141 av_freep(&c->hash);
142 av_free(c);
143 }
144
av_hmac_init(AVHMAC * c,const uint8_t * key,unsigned int keylen)145 void av_hmac_init(AVHMAC *c, const uint8_t *key, unsigned int keylen)
146 {
147 int i;
148 uint8_t block[MAX_BLOCKLEN];
149 if (keylen > c->blocklen) {
150 c->init(c->hash);
151 c->update(c->hash, key, keylen);
152 c->final(c->hash, c->key);
153 c->keylen = c->hashlen;
154 } else {
155 memcpy(c->key, key, keylen);
156 c->keylen = keylen;
157 }
158 c->init(c->hash);
159 for (i = 0; i < c->keylen; i++)
160 block[i] = c->key[i] ^ 0x36;
161 for (i = c->keylen; i < c->blocklen; i++)
162 block[i] = 0x36;
163 c->update(c->hash, block, c->blocklen);
164 }
165
av_hmac_update(AVHMAC * c,const uint8_t * data,unsigned int len)166 void av_hmac_update(AVHMAC *c, const uint8_t *data, unsigned int len)
167 {
168 c->update(c->hash, data, len);
169 }
170
av_hmac_final(AVHMAC * c,uint8_t * out,unsigned int outlen)171 int av_hmac_final(AVHMAC *c, uint8_t *out, unsigned int outlen)
172 {
173 uint8_t block[MAX_BLOCKLEN];
174 int i;
175 if (outlen < c->hashlen)
176 return AVERROR(EINVAL);
177 c->final(c->hash, out);
178 c->init(c->hash);
179 for (i = 0; i < c->keylen; i++)
180 block[i] = c->key[i] ^ 0x5C;
181 for (i = c->keylen; i < c->blocklen; i++)
182 block[i] = 0x5C;
183 c->update(c->hash, block, c->blocklen);
184 c->update(c->hash, out, c->hashlen);
185 c->final(c->hash, out);
186 return c->hashlen;
187 }
188
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)189 int av_hmac_calc(AVHMAC *c, const uint8_t *data, unsigned int len,
190 const uint8_t *key, unsigned int keylen,
191 uint8_t *out, unsigned int outlen)
192 {
193 av_hmac_init(c, key, keylen);
194 av_hmac_update(c, data, len);
195 return av_hmac_final(c, out, outlen);
196 }
197