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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 #ifdef OPENSSL_FIPS
     65 #include <openssl/fips.h>
     66 #endif
     67 
     68 int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len,
     69 		  const EVP_MD *md, ENGINE *impl)
     70 	{
     71 	int i,j,reset=0;
     72 	unsigned char pad[HMAC_MAX_MD_CBLOCK];
     73 
     74 #ifdef OPENSSL_FIPS
     75 	if (FIPS_mode())
     76 		{
     77 		/* If we have an ENGINE need to allow non FIPS */
     78 		if ((impl || ctx->i_ctx.engine)
     79 			&&  !(ctx->i_ctx.flags & EVP_CIPH_FLAG_NON_FIPS_ALLOW))
     80 			{
     81 			EVPerr(EVP_F_HMAC_INIT_EX, EVP_R_DISABLED_FOR_FIPS);
     82 			return 0;
     83 			}
     84 		/* Other algorithm blocking will be done in FIPS_cmac_init,
     85 		 * via FIPS_hmac_init_ex().
     86 		 */
     87 		if (!impl && !ctx->i_ctx.engine)
     88 			return FIPS_hmac_init_ex(ctx, key, len, md, NULL);
     89 		}
     90 #endif
     91 
     92 	if (md != NULL)
     93 		{
     94 		reset=1;
     95 		ctx->md=md;
     96 		}
     97 	else
     98 		md=ctx->md;
     99 
    100 	if (key != NULL)
    101 		{
    102 		reset=1;
    103 		j=EVP_MD_block_size(md);
    104 		OPENSSL_assert(j <= (int)sizeof(ctx->key));
    105 		if (j < len)
    106 			{
    107 			if (!EVP_DigestInit_ex(&ctx->md_ctx,md, impl))
    108 				goto err;
    109 			if (!EVP_DigestUpdate(&ctx->md_ctx,key,len))
    110 				goto err;
    111 			if (!EVP_DigestFinal_ex(&(ctx->md_ctx),ctx->key,
    112 				&ctx->key_length))
    113 				goto err;
    114 			}
    115 		else
    116 			{
    117 			OPENSSL_assert(len>=0 && len<=(int)sizeof(ctx->key));
    118 			memcpy(ctx->key,key,len);
    119 			ctx->key_length=len;
    120 			}
    121 		if(ctx->key_length != HMAC_MAX_MD_CBLOCK)
    122 			memset(&ctx->key[ctx->key_length], 0,
    123 				HMAC_MAX_MD_CBLOCK - ctx->key_length);
    124 		}
    125 
    126 	if (reset)
    127 		{
    128 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
    129 			pad[i]=0x36^ctx->key[i];
    130 		if (!EVP_DigestInit_ex(&ctx->i_ctx,md, impl))
    131 			goto err;
    132 		if (!EVP_DigestUpdate(&ctx->i_ctx,pad,EVP_MD_block_size(md)))
    133 			goto err;
    134 
    135 		for (i=0; i<HMAC_MAX_MD_CBLOCK; i++)
    136 			pad[i]=0x5c^ctx->key[i];
    137 		if (!EVP_DigestInit_ex(&ctx->o_ctx,md, impl))
    138 			goto err;
    139 		if (!EVP_DigestUpdate(&ctx->o_ctx,pad,EVP_MD_block_size(md)))
    140 			goto err;
    141 		}
    142 	if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->i_ctx))
    143 			goto err;
    144 	return 1;
    145 	err:
    146 	return 0;
    147 	}
    148 
    149 int HMAC_Init(HMAC_CTX *ctx, const void *key, int len, const EVP_MD *md)
    150 	{
    151 	if(key && md)
    152 	    HMAC_CTX_init(ctx);
    153 	return HMAC_Init_ex(ctx,key,len,md, NULL);
    154 	}
    155 
    156 int HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len)
    157 	{
    158 #ifdef OPENSSL_FIPS
    159 	if (FIPS_mode() && !ctx->i_ctx.engine)
    160 		return FIPS_hmac_update(ctx, data, len);
    161 #endif
    162 	return EVP_DigestUpdate(&ctx->md_ctx,data,len);
    163 	}
    164 
    165 int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len)
    166 	{
    167 	unsigned int i;
    168 	unsigned char buf[EVP_MAX_MD_SIZE];
    169 #ifdef OPENSSL_FIPS
    170 	if (FIPS_mode() && !ctx->i_ctx.engine)
    171 		return FIPS_hmac_final(ctx, md, len);
    172 #endif
    173 
    174 	if (!EVP_DigestFinal_ex(&ctx->md_ctx,buf,&i))
    175 		goto err;
    176 	if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->o_ctx))
    177 		goto err;
    178 	if (!EVP_DigestUpdate(&ctx->md_ctx,buf,i))
    179 		goto err;
    180 	if (!EVP_DigestFinal_ex(&ctx->md_ctx,md,len))
    181 		goto err;
    182 	return 1;
    183 	err:
    184 	return 0;
    185 	}
    186 
    187 void HMAC_CTX_init(HMAC_CTX *ctx)
    188 	{
    189 	EVP_MD_CTX_init(&ctx->i_ctx);
    190 	EVP_MD_CTX_init(&ctx->o_ctx);
    191 	EVP_MD_CTX_init(&ctx->md_ctx);
    192 	}
    193 
    194 int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx)
    195 	{
    196 	if (!EVP_MD_CTX_copy(&dctx->i_ctx, &sctx->i_ctx))
    197 		goto err;
    198 	if (!EVP_MD_CTX_copy(&dctx->o_ctx, &sctx->o_ctx))
    199 		goto err;
    200 	if (!EVP_MD_CTX_copy(&dctx->md_ctx, &sctx->md_ctx))
    201 		goto err;
    202 	memcpy(dctx->key, sctx->key, HMAC_MAX_MD_CBLOCK);
    203 	dctx->key_length = sctx->key_length;
    204 	dctx->md = sctx->md;
    205 	return 1;
    206 	err:
    207 	return 0;
    208 	}
    209 
    210 void HMAC_CTX_cleanup(HMAC_CTX *ctx)
    211 	{
    212 #ifdef OPENSSL_FIPS
    213 	if (FIPS_mode() && !ctx->i_ctx.engine)
    214 		{
    215 		FIPS_hmac_ctx_cleanup(ctx);
    216 		return;
    217 		}
    218 #endif
    219 	EVP_MD_CTX_cleanup(&ctx->i_ctx);
    220 	EVP_MD_CTX_cleanup(&ctx->o_ctx);
    221 	EVP_MD_CTX_cleanup(&ctx->md_ctx);
    222 	memset(ctx,0,sizeof *ctx);
    223 	}
    224 
    225 unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len,
    226 		    const unsigned char *d, size_t n, unsigned char *md,
    227 		    unsigned int *md_len)
    228 	{
    229 	HMAC_CTX c;
    230 	static unsigned char m[EVP_MAX_MD_SIZE];
    231 
    232 	if (md == NULL) md=m;
    233 	HMAC_CTX_init(&c);
    234 	if (!HMAC_Init(&c,key,key_len,evp_md))
    235 		goto err;
    236 	if (!HMAC_Update(&c,d,n))
    237 		goto err;
    238 	if (!HMAC_Final(&c,md,md_len))
    239 		goto err;
    240 	HMAC_CTX_cleanup(&c);
    241 	return md;
    242 	err:
    243 	return NULL;
    244 	}
    245 
    246 void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags)
    247 	{
    248 	EVP_MD_CTX_set_flags(&ctx->i_ctx, flags);
    249 	EVP_MD_CTX_set_flags(&ctx->o_ctx, flags);
    250 	EVP_MD_CTX_set_flags(&ctx->md_ctx, flags);
    251 	}
    252