1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.] */
57 #include <openssl/hmac.h>
61 #include <openssl/mem.h>
64 uint8_t *HMAC(const EVP_MD *evp_md, const void *key, size_t key_len,
65 const uint8_t *data, size_t data_len, uint8_t *out,
66 unsigned int *out_len) {
68 static uint8_t static_out_buffer[EVP_MAX_MD_SIZE];
70 /* OpenSSL has traditionally supported using a static buffer if |out| is
71 * NULL. We maintain that but don't document it. This behaviour should be
72 * considered to be deprecated. */
74 out = static_out_buffer;
78 if (!HMAC_Init(&ctx, key, key_len, evp_md) ||
79 !HMAC_Update(&ctx, data, data_len) ||
80 !HMAC_Final(&ctx, out, out_len)) {
84 HMAC_CTX_cleanup(&ctx);
88 void HMAC_CTX_init(HMAC_CTX *ctx) {
89 EVP_MD_CTX_init(&ctx->i_ctx);
90 EVP_MD_CTX_init(&ctx->o_ctx);
91 EVP_MD_CTX_init(&ctx->md_ctx);
94 void HMAC_CTX_cleanup(HMAC_CTX *ctx) {
95 EVP_MD_CTX_cleanup(&ctx->i_ctx);
96 EVP_MD_CTX_cleanup(&ctx->o_ctx);
97 EVP_MD_CTX_cleanup(&ctx->md_ctx);
98 OPENSSL_cleanse(ctx, sizeof(ctx));
101 int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, size_t key_len,
102 const EVP_MD *md, ENGINE *impl) {
103 unsigned i, reset = 0;
104 uint8_t pad[HMAC_MAX_MD_CBLOCK];
114 size_t block_size = EVP_MD_block_size(md);
116 assert(block_size <= sizeof(ctx->key));
117 if (block_size < key_len) {
118 if (!EVP_DigestInit_ex(&ctx->md_ctx, md, impl) ||
119 !EVP_DigestUpdate(&ctx->md_ctx, key, key_len) ||
120 !EVP_DigestFinal_ex(&(ctx->md_ctx), ctx->key, &ctx->key_length)) {
124 assert(key_len >= 0 && key_len <= sizeof(ctx->key));
125 memcpy(ctx->key, key, key_len);
126 ctx->key_length = key_len;
128 if (ctx->key_length != HMAC_MAX_MD_CBLOCK) {
129 memset(&ctx->key[ctx->key_length], 0, sizeof(ctx->key) - ctx->key_length);
134 for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) {
135 pad[i] = 0x36 ^ ctx->key[i];
137 if (!EVP_DigestInit_ex(&ctx->i_ctx, md, impl) ||
138 !EVP_DigestUpdate(&ctx->i_ctx, pad, EVP_MD_block_size(md))) {
142 for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) {
143 pad[i] = 0x5c ^ ctx->key[i];
145 if (!EVP_DigestInit_ex(&ctx->o_ctx, md, impl) ||
146 !EVP_DigestUpdate(&ctx->o_ctx, pad, EVP_MD_block_size(md))) {
151 if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->i_ctx)) {
161 int HMAC_Update(HMAC_CTX *ctx, const uint8_t *data, size_t data_len) {
162 return EVP_DigestUpdate(&ctx->md_ctx, data, data_len);
165 int HMAC_Final(HMAC_CTX *ctx, uint8_t *out, unsigned int *out_len) {
167 uint8_t buf[EVP_MAX_MD_SIZE];
169 if (!EVP_DigestFinal_ex(&ctx->md_ctx, buf, &i) ||
170 !EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->o_ctx) ||
171 !EVP_DigestUpdate(&ctx->md_ctx, buf, i) ||
172 !EVP_DigestFinal_ex(&ctx->md_ctx, out, out_len)) {
180 size_t HMAC_size(const HMAC_CTX *ctx) {
181 return EVP_MD_size(ctx->md);
184 int HMAC_CTX_copy(HMAC_CTX *dest, const HMAC_CTX *src) {
185 if (!EVP_MD_CTX_copy(&dest->i_ctx, &src->i_ctx) ||
186 !EVP_MD_CTX_copy(&dest->o_ctx, &src->o_ctx) ||
187 !EVP_MD_CTX_copy(&dest->md_ctx, &src->md_ctx)) {
191 memcpy(dest->key, src->key, HMAC_MAX_MD_CBLOCK);
192 dest->key_length = src->key_length;
197 void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags) {
198 EVP_MD_CTX_set_flags(&ctx->i_ctx, flags);
199 EVP_MD_CTX_set_flags(&ctx->o_ctx, flags);
200 EVP_MD_CTX_set_flags(&ctx->md_ctx, flags);
203 int HMAC_Init(HMAC_CTX *ctx, const void *key, int key_len, const EVP_MD *md) {
207 return HMAC_Init_ex(ctx, key, key_len, md, NULL);