1/*	$OpenBSD: hmac.c,v 1.4 2016/09/19 18:09:40 tedu Exp $	*/
2
3/*-
4 * Copyright (c) 2008 Damien Bergamini <damien.bergamini@free.fr>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19/*
20 * This code implements the HMAC algorithm described in RFC 2104 using
21 * the MD5, SHA1 and SHA-256 hash functions.
22 */
23
24#include <sys/param.h>
25#include <sys/systm.h>
26
27#include <crypto/md5.h>
28#include <crypto/sha1.h>
29#include <crypto/sha2.h>
30#include <crypto/hmac.h>
31
32void
33HMAC_MD5_Init(HMAC_MD5_CTX *ctx, const u_int8_t *key, u_int key_len)
34{
35	u_int8_t k_ipad[MD5_BLOCK_LENGTH];
36	int i;
37
38	if (key_len > MD5_BLOCK_LENGTH) {
39		MD5Init(&ctx->ctx);
40		MD5Update(&ctx->ctx, key, key_len);
41		MD5Final(ctx->key, &ctx->ctx);
42		ctx->key_len = MD5_DIGEST_LENGTH;
43	} else {
44		bcopy(key, ctx->key, key_len);
45		ctx->key_len = key_len;
46	}
47
48	bzero(k_ipad, MD5_BLOCK_LENGTH);
49	memcpy(k_ipad, ctx->key, ctx->key_len);
50	for (i = 0; i < MD5_BLOCK_LENGTH; i++)
51		k_ipad[i] ^= 0x36;
52
53	MD5Init(&ctx->ctx);
54	MD5Update(&ctx->ctx, k_ipad, MD5_BLOCK_LENGTH);
55
56	explicit_bzero(k_ipad, sizeof k_ipad);
57}
58
59void
60HMAC_MD5_Update(HMAC_MD5_CTX *ctx, const u_int8_t *data, u_int len)
61{
62	MD5Update(&ctx->ctx, data, len);
63}
64
65void
66HMAC_MD5_Final(u_int8_t digest[MD5_DIGEST_LENGTH], HMAC_MD5_CTX *ctx)
67{
68	u_int8_t k_opad[MD5_BLOCK_LENGTH];
69	int i;
70
71	MD5Final(digest, &ctx->ctx);
72
73	bzero(k_opad, MD5_BLOCK_LENGTH);
74	memcpy(k_opad, ctx->key, ctx->key_len);
75	for (i = 0; i < MD5_BLOCK_LENGTH; i++)
76		k_opad[i] ^= 0x5c;
77
78	MD5Init(&ctx->ctx);
79	MD5Update(&ctx->ctx, k_opad, MD5_BLOCK_LENGTH);
80	MD5Update(&ctx->ctx, digest, MD5_DIGEST_LENGTH);
81	MD5Final(digest, &ctx->ctx);
82
83	explicit_bzero(k_opad, sizeof k_opad);
84}
85
86void
87HMAC_SHA1_Init(HMAC_SHA1_CTX *ctx, const u_int8_t *key, u_int key_len)
88{
89	u_int8_t k_ipad[SHA1_BLOCK_LENGTH];
90	int i;
91
92	if (key_len > SHA1_BLOCK_LENGTH) {
93		SHA1Init(&ctx->ctx);
94		SHA1Update(&ctx->ctx, key, key_len);
95		SHA1Final(ctx->key, &ctx->ctx);
96		ctx->key_len = SHA1_DIGEST_LENGTH;
97	} else {
98		bcopy(key, ctx->key, key_len);
99		ctx->key_len = key_len;
100	}
101
102	bzero(k_ipad, SHA1_BLOCK_LENGTH);
103	memcpy(k_ipad, ctx->key, ctx->key_len);
104	for (i = 0; i < SHA1_BLOCK_LENGTH; i++)
105		k_ipad[i] ^= 0x36;
106
107	SHA1Init(&ctx->ctx);
108	SHA1Update(&ctx->ctx, k_ipad, SHA1_BLOCK_LENGTH);
109
110	explicit_bzero(k_ipad, sizeof k_ipad);
111}
112
113void
114HMAC_SHA1_Update(HMAC_SHA1_CTX *ctx, const u_int8_t *data, u_int len)
115{
116	SHA1Update(&ctx->ctx, data, len);
117}
118
119void
120HMAC_SHA1_Final(u_int8_t digest[SHA1_DIGEST_LENGTH], HMAC_SHA1_CTX *ctx)
121{
122	u_int8_t k_opad[SHA1_BLOCK_LENGTH];
123	int i;
124
125	SHA1Final(digest, &ctx->ctx);
126
127	bzero(k_opad, SHA1_BLOCK_LENGTH);
128	memcpy(k_opad, ctx->key, ctx->key_len);
129	for (i = 0; i < SHA1_BLOCK_LENGTH; i++)
130		k_opad[i] ^= 0x5c;
131
132	SHA1Init(&ctx->ctx);
133	SHA1Update(&ctx->ctx, k_opad, SHA1_BLOCK_LENGTH);
134	SHA1Update(&ctx->ctx, digest, SHA1_DIGEST_LENGTH);
135	SHA1Final(digest, &ctx->ctx);
136
137	explicit_bzero(k_opad, sizeof k_opad);
138}
139
140void
141HMAC_SHA256_Init(HMAC_SHA256_CTX *ctx, const u_int8_t *key, u_int key_len)
142{
143	u_int8_t k_ipad[SHA256_BLOCK_LENGTH];
144	int i;
145
146	if (key_len > SHA256_BLOCK_LENGTH) {
147		SHA256Init(&ctx->ctx);
148		SHA256Update(&ctx->ctx, key, key_len);
149		SHA256Final(ctx->key, &ctx->ctx);
150		ctx->key_len = SHA256_DIGEST_LENGTH;
151	} else {
152		bcopy(key, ctx->key, key_len);
153		ctx->key_len = key_len;
154	}
155
156	bzero(k_ipad, SHA256_BLOCK_LENGTH);
157	memcpy(k_ipad, ctx->key, ctx->key_len);
158	for (i = 0; i < SHA256_BLOCK_LENGTH; i++)
159		k_ipad[i] ^= 0x36;
160
161	SHA256Init(&ctx->ctx);
162	SHA256Update(&ctx->ctx, k_ipad, SHA256_BLOCK_LENGTH);
163
164	explicit_bzero(k_ipad, sizeof k_ipad);
165}
166
167void
168HMAC_SHA256_Update(HMAC_SHA256_CTX *ctx, const u_int8_t *data, u_int len)
169{
170	SHA256Update(&ctx->ctx, data, len);
171}
172
173void
174HMAC_SHA256_Final(u_int8_t digest[SHA256_DIGEST_LENGTH], HMAC_SHA256_CTX *ctx)
175{
176	u_int8_t k_opad[SHA256_BLOCK_LENGTH];
177	int i;
178
179	SHA256Final(digest, &ctx->ctx);
180
181	bzero(k_opad, SHA256_BLOCK_LENGTH);
182	memcpy(k_opad, ctx->key, ctx->key_len);
183	for (i = 0; i < SHA256_BLOCK_LENGTH; i++)
184		k_opad[i] ^= 0x5c;
185
186	SHA256Init(&ctx->ctx);
187	SHA256Update(&ctx->ctx, k_opad, SHA256_BLOCK_LENGTH);
188	SHA256Update(&ctx->ctx, digest, SHA256_DIGEST_LENGTH);
189	SHA256Final(digest, &ctx->ctx);
190
191	explicit_bzero(k_opad, sizeof k_opad);
192}
193