1 /* Copyright (C) 1995-1998 Eric Young ([email protected])
2 * All rights reserved.
3 *
4 * This package is an SSL implementation written
5 * by Eric Young ([email protected]).
6 * The implementation was written so as to conform with Netscapes SSL.
7 *
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 ([email protected]).
14 *
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.
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
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 ([email protected])"
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 ([email protected])"
39 *
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
50 * SUCH DAMAGE.
51 *
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.] */
56
57 #include <openssl/hmac.h>
58
59 #include <assert.h>
60 #include <string.h>
61
62 #include <openssl/digest.h>
63 #include <openssl/mem.h>
64
65 #include "../../internal.h"
66 #include "../service_indicator/internal.h"
67
68
HMAC(const EVP_MD * evp_md,const void * key,size_t key_len,const uint8_t * data,size_t data_len,uint8_t * out,unsigned int * out_len)69 uint8_t *HMAC(const EVP_MD *evp_md, const void *key, size_t key_len,
70 const uint8_t *data, size_t data_len, uint8_t *out,
71 unsigned int *out_len) {
72 HMAC_CTX ctx;
73 HMAC_CTX_init(&ctx);
74
75 // The underlying hash functions should not set the FIPS service indicator
76 // until all operations have completed.
77 FIPS_service_indicator_lock_state();
78 const int ok = HMAC_Init_ex(&ctx, key, key_len, evp_md, NULL) &&
79 HMAC_Update(&ctx, data, data_len) &&
80 HMAC_Final(&ctx, out, out_len);
81 FIPS_service_indicator_unlock_state();
82
83 HMAC_CTX_cleanup(&ctx);
84
85 if (!ok) {
86 return NULL;
87 }
88
89 HMAC_verify_service_indicator(evp_md);
90 return out;
91 }
92
HMAC_CTX_init(HMAC_CTX * ctx)93 void HMAC_CTX_init(HMAC_CTX *ctx) {
94 ctx->md = NULL;
95 EVP_MD_CTX_init(&ctx->i_ctx);
96 EVP_MD_CTX_init(&ctx->o_ctx);
97 EVP_MD_CTX_init(&ctx->md_ctx);
98 }
99
HMAC_CTX_new(void)100 HMAC_CTX *HMAC_CTX_new(void) {
101 HMAC_CTX *ctx = OPENSSL_malloc(sizeof(HMAC_CTX));
102 if (ctx != NULL) {
103 HMAC_CTX_init(ctx);
104 }
105 return ctx;
106 }
107
HMAC_CTX_cleanup(HMAC_CTX * ctx)108 void HMAC_CTX_cleanup(HMAC_CTX *ctx) {
109 EVP_MD_CTX_cleanup(&ctx->i_ctx);
110 EVP_MD_CTX_cleanup(&ctx->o_ctx);
111 EVP_MD_CTX_cleanup(&ctx->md_ctx);
112 OPENSSL_cleanse(ctx, sizeof(HMAC_CTX));
113 }
114
HMAC_CTX_cleanse(HMAC_CTX * ctx)115 void HMAC_CTX_cleanse(HMAC_CTX *ctx) {
116 EVP_MD_CTX_cleanse(&ctx->i_ctx);
117 EVP_MD_CTX_cleanse(&ctx->o_ctx);
118 EVP_MD_CTX_cleanse(&ctx->md_ctx);
119 OPENSSL_cleanse(ctx, sizeof(HMAC_CTX));
120 }
121
HMAC_CTX_free(HMAC_CTX * ctx)122 void HMAC_CTX_free(HMAC_CTX *ctx) {
123 if (ctx == NULL) {
124 return;
125 }
126
127 HMAC_CTX_cleanup(ctx);
128 OPENSSL_free(ctx);
129 }
130
HMAC_Init_ex(HMAC_CTX * ctx,const void * key,size_t key_len,const EVP_MD * md,ENGINE * impl)131 int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, size_t key_len,
132 const EVP_MD *md, ENGINE *impl) {
133 int ret = 0;
134 FIPS_service_indicator_lock_state();
135
136 if (md == NULL) {
137 md = ctx->md;
138 }
139
140 // If either |key| is non-NULL or |md| has changed, initialize with a new key
141 // rather than rewinding the previous one.
142 //
143 // TODO(davidben,eroman): Passing the previous |md| with a NULL |key| is
144 // ambiguous between using the empty key and reusing the previous key. There
145 // exist callers which intend the latter, but the former is an awkward edge
146 // case. Fix to API to avoid this.
147 if (md != ctx->md || key != NULL) {
148 uint8_t pad[EVP_MAX_MD_BLOCK_SIZE];
149 uint8_t key_block[EVP_MAX_MD_BLOCK_SIZE];
150 unsigned key_block_len;
151
152 size_t block_size = EVP_MD_block_size(md);
153 assert(block_size <= sizeof(key_block));
154 assert(EVP_MD_size(md) <= block_size);
155 if (block_size < key_len) {
156 // Long keys are hashed.
157 if (!EVP_DigestInit_ex(&ctx->md_ctx, md, impl) ||
158 !EVP_DigestUpdate(&ctx->md_ctx, key, key_len) ||
159 !EVP_DigestFinal_ex(&ctx->md_ctx, key_block, &key_block_len)) {
160 goto out;
161 }
162 } else {
163 assert(key_len <= sizeof(key_block));
164 OPENSSL_memcpy(key_block, key, key_len);
165 key_block_len = (unsigned)key_len;
166 }
167 // Keys are then padded with zeros.
168 OPENSSL_memset(key_block + key_block_len, 0, block_size - key_block_len);
169
170 for (size_t i = 0; i < block_size; i++) {
171 pad[i] = 0x36 ^ key_block[i];
172 }
173 if (!EVP_DigestInit_ex(&ctx->i_ctx, md, impl) ||
174 !EVP_DigestUpdate(&ctx->i_ctx, pad, block_size)) {
175 goto out;
176 }
177
178 for (size_t i = 0; i < block_size; i++) {
179 pad[i] = 0x5c ^ key_block[i];
180 }
181 if (!EVP_DigestInit_ex(&ctx->o_ctx, md, impl) ||
182 !EVP_DigestUpdate(&ctx->o_ctx, pad, block_size)) {
183 goto out;
184 }
185
186 ctx->md = md;
187 }
188
189 ret = EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->i_ctx);
190
191 out:
192 FIPS_service_indicator_unlock_state();
193 return ret;
194 }
195
HMAC_Update(HMAC_CTX * ctx,const uint8_t * data,size_t data_len)196 int HMAC_Update(HMAC_CTX *ctx, const uint8_t *data, size_t data_len) {
197 return EVP_DigestUpdate(&ctx->md_ctx, data, data_len);
198 }
199
HMAC_Final(HMAC_CTX * ctx,uint8_t * out,unsigned int * out_len)200 int HMAC_Final(HMAC_CTX *ctx, uint8_t *out, unsigned int *out_len) {
201 int ret = 0;
202 unsigned int i;
203 uint8_t buf[EVP_MAX_MD_SIZE];
204
205 FIPS_service_indicator_lock_state();
206 // TODO(davidben): The only thing that can officially fail here is
207 // |EVP_MD_CTX_copy_ex|, but even that should be impossible in this case.
208 if (!EVP_DigestFinal_ex(&ctx->md_ctx, buf, &i) ||
209 !EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->o_ctx) ||
210 !EVP_DigestUpdate(&ctx->md_ctx, buf, i) ||
211 !EVP_DigestFinal_ex(&ctx->md_ctx, out, out_len)) {
212 *out_len = 0;
213 goto out;
214 }
215
216 ret = 1;
217
218 out:
219 FIPS_service_indicator_unlock_state();
220 if (ret) {
221 HMAC_verify_service_indicator(ctx->md);
222 }
223 return ret;
224 }
225
HMAC_size(const HMAC_CTX * ctx)226 size_t HMAC_size(const HMAC_CTX *ctx) { return EVP_MD_size(ctx->md); }
227
HMAC_CTX_get_md(const HMAC_CTX * ctx)228 const EVP_MD *HMAC_CTX_get_md(const HMAC_CTX *ctx) { return ctx->md; }
229
HMAC_CTX_copy_ex(HMAC_CTX * dest,const HMAC_CTX * src)230 int HMAC_CTX_copy_ex(HMAC_CTX *dest, const HMAC_CTX *src) {
231 if (!EVP_MD_CTX_copy_ex(&dest->i_ctx, &src->i_ctx) ||
232 !EVP_MD_CTX_copy_ex(&dest->o_ctx, &src->o_ctx) ||
233 !EVP_MD_CTX_copy_ex(&dest->md_ctx, &src->md_ctx)) {
234 return 0;
235 }
236
237 dest->md = src->md;
238 return 1;
239 }
240
HMAC_CTX_reset(HMAC_CTX * ctx)241 void HMAC_CTX_reset(HMAC_CTX *ctx) {
242 HMAC_CTX_cleanup(ctx);
243 HMAC_CTX_init(ctx);
244 }
245
HMAC_Init(HMAC_CTX * ctx,const void * key,int key_len,const EVP_MD * md)246 int HMAC_Init(HMAC_CTX *ctx, const void *key, int key_len, const EVP_MD *md) {
247 if (key && md) {
248 HMAC_CTX_init(ctx);
249 }
250 return HMAC_Init_ex(ctx, key, key_len, md, NULL);
251 }
252
HMAC_CTX_copy(HMAC_CTX * dest,const HMAC_CTX * src)253 int HMAC_CTX_copy(HMAC_CTX *dest, const HMAC_CTX *src) {
254 HMAC_CTX_init(dest);
255 return HMAC_CTX_copy_ex(dest, src);
256 }
257