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      1 /* crypto/hmac/hmac.c */
      2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      3  * All rights reserved.
      4  *
      5  * This package is an SSL implementation written
      6  * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 
     64 #ifndef OPENSSL_FIPS
     65 
     66 void HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len,
     67 		  const EVP_MD *md, ENGINE *impl)
     68 	{
     69 	int i,j,reset=0;
     70 	unsigned char pad[HMAC_MAX_MD_CBLOCK];
     71 
     72 	if (md != NULL)
     73 		{
     74 		reset=1;
     75 		ctx->md=md;
     76 		}
     77 	else
     78 		md=ctx->md;
     79 
     80 	if (key != NULL)
     81 		{
     82 		reset=1;
     83 		j=EVP_MD_block_size(md);
     84 		OPENSSL_assert(j <= (int)sizeof(ctx->key));
     85 		if (j < len)
     86 			{
     87 			EVP_DigestInit_ex(&ctx->md_ctx,md, impl);
     88 			EVP_DigestUpdate(&ctx->md_ctx,key,len);
     89 			EVP_DigestFinal_ex(&(ctx->md_ctx),ctx->key,
     90 				&ctx->key_length);
     91 			}
     92 		else
     93 			{
     94 			OPENSSL_assert(len>=0 && len<=(int)sizeof(ctx->key));
     95 			memcpy(ctx->key,key,len);
     96 			ctx->key_length=len;
     97 			}
     98 		if(ctx->key_length != HMAC_MAX_MD_CBLOCK)
     99 			memset(&ctx->key[ctx->key_length], 0,
    100 				HMAC_MAX_MD_CBLOCK - ctx->key_length);
    101 		}
    102 
    103 	if (reset)
    104 		{
    105 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
    106 			pad[i]=0x36^ctx->key[i];
    107 		EVP_DigestInit_ex(&ctx->i_ctx,md, impl);
    108 		EVP_DigestUpdate(&ctx->i_ctx,pad,EVP_MD_block_size(md));
    109 
    110 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
    111 			pad[i]=0x5c^ctx->key[i];
    112 		EVP_DigestInit_ex(&ctx->o_ctx,md, impl);
    113 		EVP_DigestUpdate(&ctx->o_ctx,pad,EVP_MD_block_size(md));
    114 		}
    115 	EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->i_ctx);
    116 	}
    117 
    118 void HMAC_Init(HMAC_CTX *ctx, const void *key, int len,
    119 	       const EVP_MD *md)
    120 	{
    121 	if(key && md)
    122 	    HMAC_CTX_init(ctx);
    123 	HMAC_Init_ex(ctx,key,len,md, NULL);
    124 	}
    125 
    126 void HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len)
    127 	{
    128 	EVP_DigestUpdate(&ctx->md_ctx,data,len);
    129 	}
    130 
    131 void HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len)
    132 	{
    133 	int j;
    134 	unsigned int i;
    135 	unsigned char buf[EVP_MAX_MD_SIZE];
    136 
    137 	j=EVP_MD_block_size(ctx->md);
    138 
    139 	EVP_DigestFinal_ex(&ctx->md_ctx,buf,&i);
    140 	EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->o_ctx);
    141 	EVP_DigestUpdate(&ctx->md_ctx,buf,i);
    142 	EVP_DigestFinal_ex(&ctx->md_ctx,md,len);
    143 	}
    144 
    145 void HMAC_CTX_init(HMAC_CTX *ctx)
    146 	{
    147 	EVP_MD_CTX_init(&ctx->i_ctx);
    148 	EVP_MD_CTX_init(&ctx->o_ctx);
    149 	EVP_MD_CTX_init(&ctx->md_ctx);
    150 	}
    151 
    152 void HMAC_CTX_cleanup(HMAC_CTX *ctx)
    153 	{
    154 	EVP_MD_CTX_cleanup(&ctx->i_ctx);
    155 	EVP_MD_CTX_cleanup(&ctx->o_ctx);
    156 	EVP_MD_CTX_cleanup(&ctx->md_ctx);
    157 	memset(ctx,0,sizeof *ctx);
    158 	}
    159 
    160 unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len,
    161 		    const unsigned char *d, size_t n, unsigned char *md,
    162 		    unsigned int *md_len)
    163 	{
    164 	HMAC_CTX c;
    165 	static unsigned char m[EVP_MAX_MD_SIZE];
    166 
    167 	if (md == NULL) md=m;
    168 	HMAC_CTX_init(&c);
    169 	HMAC_Init(&c,key,key_len,evp_md);
    170 	HMAC_Update(&c,d,n);
    171 	HMAC_Final(&c,md,md_len);
    172 	HMAC_CTX_cleanup(&c);
    173 	return(md);
    174 	}
    175 
    176 void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags)
    177 	{
    178 	EVP_MD_CTX_set_flags(&ctx->i_ctx, flags);
    179 	EVP_MD_CTX_set_flags(&ctx->o_ctx, flags);
    180 	EVP_MD_CTX_set_flags(&ctx->md_ctx, flags);
    181 	}
    182 
    183 #endif
    184