• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 void 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 			EVP_DigestInit_ex(&ctx->md_ctx,md, impl);
86 			EVP_DigestUpdate(&ctx->md_ctx,key,len);
87 			EVP_DigestFinal_ex(&(ctx->md_ctx),ctx->key,
88 				&ctx->key_length);
89 			}
90 		else
91 			{
92 			OPENSSL_assert(len>=0 && len<=(int)sizeof(ctx->key));
93 			memcpy(ctx->key,key,len);
94 			ctx->key_length=len;
95 			}
96 		if(ctx->key_length != HMAC_MAX_MD_CBLOCK)
97 			memset(&ctx->key[ctx->key_length], 0,
98 				HMAC_MAX_MD_CBLOCK - ctx->key_length);
99 		}
100 
101 	if (reset)
102 		{
103 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
104 			pad[i]=0x36^ctx->key[i];
105 		EVP_DigestInit_ex(&ctx->i_ctx,md, impl);
106 		EVP_DigestUpdate(&ctx->i_ctx,pad,EVP_MD_block_size(md));
107 
108 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
109 			pad[i]=0x5c^ctx->key[i];
110 		EVP_DigestInit_ex(&ctx->o_ctx,md, impl);
111 		EVP_DigestUpdate(&ctx->o_ctx,pad,EVP_MD_block_size(md));
112 		}
113 	EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->i_ctx);
114 	}
115 
HMAC_Init(HMAC_CTX * ctx,const void * key,int len,const EVP_MD * md)116 void HMAC_Init(HMAC_CTX *ctx, const void *key, int len,
117 	       const EVP_MD *md)
118 	{
119 	if(key && md)
120 	    HMAC_CTX_init(ctx);
121 	HMAC_Init_ex(ctx,key,len,md, NULL);
122 	}
123 
HMAC_Update(HMAC_CTX * ctx,const unsigned char * data,size_t len)124 void HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len)
125 	{
126 	EVP_DigestUpdate(&ctx->md_ctx,data,len);
127 	}
128 
HMAC_Final(HMAC_CTX * ctx,unsigned char * md,unsigned int * len)129 void HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len)
130 	{
131 	int j;
132 	unsigned int i;
133 	unsigned char buf[EVP_MAX_MD_SIZE];
134 
135 	j=EVP_MD_block_size(ctx->md);
136 
137 	EVP_DigestFinal_ex(&ctx->md_ctx,buf,&i);
138 	EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->o_ctx);
139 	EVP_DigestUpdate(&ctx->md_ctx,buf,i);
140 	EVP_DigestFinal_ex(&ctx->md_ctx,md,len);
141 	}
142 
HMAC_CTX_init(HMAC_CTX * ctx)143 void HMAC_CTX_init(HMAC_CTX *ctx)
144 	{
145 	EVP_MD_CTX_init(&ctx->i_ctx);
146 	EVP_MD_CTX_init(&ctx->o_ctx);
147 	EVP_MD_CTX_init(&ctx->md_ctx);
148 	}
149 
HMAC_CTX_cleanup(HMAC_CTX * ctx)150 void HMAC_CTX_cleanup(HMAC_CTX *ctx)
151 	{
152 	EVP_MD_CTX_cleanup(&ctx->i_ctx);
153 	EVP_MD_CTX_cleanup(&ctx->o_ctx);
154 	EVP_MD_CTX_cleanup(&ctx->md_ctx);
155 	memset(ctx,0,sizeof *ctx);
156 	}
157 
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)158 unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len,
159 		    const unsigned char *d, size_t n, unsigned char *md,
160 		    unsigned int *md_len)
161 	{
162 	HMAC_CTX c;
163 	static unsigned char m[EVP_MAX_MD_SIZE];
164 
165 	if (md == NULL) md=m;
166 	HMAC_CTX_init(&c);
167 	HMAC_Init(&c,key,key_len,evp_md);
168 	HMAC_Update(&c,d,n);
169 	HMAC_Final(&c,md,md_len);
170 	HMAC_CTX_cleanup(&c);
171 	return(md);
172 	}
173 
174