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1 /* crypto/hmac/hmac.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include "cryptlib.h"
62 #include <openssl/hmac.h>
63 
HMAC_Init_ex(HMAC_CTX * ctx,const void * key,int len,const EVP_MD * md,ENGINE * impl)64 int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len,
65 		  const EVP_MD *md, ENGINE *impl)
66 	{
67 	int i,j,reset=0;
68 	unsigned char pad[HMAC_MAX_MD_CBLOCK];
69 
70 	if (md != NULL)
71 		{
72 		reset=1;
73 		ctx->md=md;
74 		}
75 	else
76 		md=ctx->md;
77 
78 	if (key != NULL)
79 		{
80 		reset=1;
81 		j=EVP_MD_block_size(md);
82 		OPENSSL_assert(j <= (int)sizeof(ctx->key));
83 		if (j < len)
84 			{
85 			if (!EVP_DigestInit_ex(&ctx->md_ctx,md, impl))
86 				goto err;
87 			if (!EVP_DigestUpdate(&ctx->md_ctx,key,len))
88 				goto err;
89 			if (!EVP_DigestFinal_ex(&(ctx->md_ctx),ctx->key,
90 				&ctx->key_length))
91 				goto err;
92 			}
93 		else
94 			{
95 			OPENSSL_assert(len>=0 && len<=(int)sizeof(ctx->key));
96 			memcpy(ctx->key,key,len);
97 			ctx->key_length=len;
98 			}
99 		if(ctx->key_length != HMAC_MAX_MD_CBLOCK)
100 			memset(&ctx->key[ctx->key_length], 0,
101 				HMAC_MAX_MD_CBLOCK - ctx->key_length);
102 		}
103 
104 	if (reset)
105 		{
106 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
107 			pad[i]=0x36^ctx->key[i];
108 		if (!EVP_DigestInit_ex(&ctx->i_ctx,md, impl))
109 			goto err;
110 		if (!EVP_DigestUpdate(&ctx->i_ctx,pad,EVP_MD_block_size(md)))
111 			goto err;
112 
113 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
114 			pad[i]=0x5c^ctx->key[i];
115 		if (!EVP_DigestInit_ex(&ctx->o_ctx,md, impl))
116 			goto err;
117 		if (!EVP_DigestUpdate(&ctx->o_ctx,pad,EVP_MD_block_size(md)))
118 			goto err;
119 		}
120 	if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->i_ctx))
121 			goto err;
122 	return 1;
123 	err:
124 	return 0;
125 	}
126 
HMAC_Init(HMAC_CTX * ctx,const void * key,int len,const EVP_MD * md)127 int HMAC_Init(HMAC_CTX *ctx, const void *key, int len, const EVP_MD *md)
128 	{
129 	if(key && md)
130 	    HMAC_CTX_init(ctx);
131 	return HMAC_Init_ex(ctx,key,len,md, NULL);
132 	}
133 
HMAC_Update(HMAC_CTX * ctx,const unsigned char * data,size_t len)134 int HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len)
135 	{
136 	return EVP_DigestUpdate(&ctx->md_ctx,data,len);
137 	}
138 
HMAC_Final(HMAC_CTX * ctx,unsigned char * md,unsigned int * len)139 int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len)
140 	{
141 	int j;
142 	unsigned int i;
143 	unsigned char buf[EVP_MAX_MD_SIZE];
144 
145 	j=EVP_MD_block_size(ctx->md);
146 
147 	if (!EVP_DigestFinal_ex(&ctx->md_ctx,buf,&i))
148 		goto err;
149 	if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->o_ctx))
150 		goto err;
151 	if (!EVP_DigestUpdate(&ctx->md_ctx,buf,i))
152 		goto err;
153 	if (!EVP_DigestFinal_ex(&ctx->md_ctx,md,len))
154 		goto err;
155 	return 1;
156 	err:
157 	return 0;
158 	}
159 
HMAC_CTX_init(HMAC_CTX * ctx)160 void HMAC_CTX_init(HMAC_CTX *ctx)
161 	{
162 	EVP_MD_CTX_init(&ctx->i_ctx);
163 	EVP_MD_CTX_init(&ctx->o_ctx);
164 	EVP_MD_CTX_init(&ctx->md_ctx);
165 	}
166 
HMAC_CTX_copy(HMAC_CTX * dctx,HMAC_CTX * sctx)167 int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx)
168 	{
169 	if (!EVP_MD_CTX_copy(&dctx->i_ctx, &sctx->i_ctx))
170 		goto err;
171 	if (!EVP_MD_CTX_copy(&dctx->o_ctx, &sctx->o_ctx))
172 		goto err;
173 	if (!EVP_MD_CTX_copy(&dctx->md_ctx, &sctx->md_ctx))
174 		goto err;
175 	memcpy(dctx->key, sctx->key, HMAC_MAX_MD_CBLOCK);
176 	dctx->key_length = sctx->key_length;
177 	dctx->md = sctx->md;
178 	return 1;
179 	err:
180 	return 0;
181 	}
182 
HMAC_CTX_cleanup(HMAC_CTX * ctx)183 void HMAC_CTX_cleanup(HMAC_CTX *ctx)
184 	{
185 	EVP_MD_CTX_cleanup(&ctx->i_ctx);
186 	EVP_MD_CTX_cleanup(&ctx->o_ctx);
187 	EVP_MD_CTX_cleanup(&ctx->md_ctx);
188 	memset(ctx,0,sizeof *ctx);
189 	}
190 
HMAC(const EVP_MD * evp_md,const void * key,int key_len,const unsigned char * d,size_t n,unsigned char * md,unsigned int * md_len)191 unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len,
192 		    const unsigned char *d, size_t n, unsigned char *md,
193 		    unsigned int *md_len)
194 	{
195 	HMAC_CTX c;
196 	static unsigned char m[EVP_MAX_MD_SIZE];
197 
198 	if (md == NULL) md=m;
199 	HMAC_CTX_init(&c);
200 	if (!HMAC_Init(&c,key,key_len,evp_md))
201 		goto err;
202 	if (!HMAC_Update(&c,d,n))
203 		goto err;
204 	if (!HMAC_Final(&c,md,md_len))
205 		goto err;
206 	HMAC_CTX_cleanup(&c);
207 	return md;
208 	err:
209 	return NULL;
210 	}
211 
HMAC_CTX_set_flags(HMAC_CTX * ctx,unsigned long flags)212 void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags)
213 	{
214 	EVP_MD_CTX_set_flags(&ctx->i_ctx, flags);
215 	EVP_MD_CTX_set_flags(&ctx->o_ctx, flags);
216 	EVP_MD_CTX_set_flags(&ctx->md_ctx, flags);
217 	}
218