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 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 } 126 127 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 } 133 134 int HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len) 135 { 136 return EVP_DigestUpdate(&ctx->md_ctx,data,len); 137 } 138 139 int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len) 140 { 141 unsigned int i; 142 unsigned char buf[EVP_MAX_MD_SIZE]; 143 144 if (!EVP_DigestFinal_ex(&ctx->md_ctx,buf,&i)) 145 goto err; 146 if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx,&ctx->o_ctx)) 147 goto err; 148 if (!EVP_DigestUpdate(&ctx->md_ctx,buf,i)) 149 goto err; 150 if (!EVP_DigestFinal_ex(&ctx->md_ctx,md,len)) 151 goto err; 152 return 1; 153 err: 154 return 0; 155 } 156 157 void HMAC_CTX_init(HMAC_CTX *ctx) 158 { 159 EVP_MD_CTX_init(&ctx->i_ctx); 160 EVP_MD_CTX_init(&ctx->o_ctx); 161 EVP_MD_CTX_init(&ctx->md_ctx); 162 } 163 164 int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx) 165 { 166 if (!EVP_MD_CTX_copy(&dctx->i_ctx, &sctx->i_ctx)) 167 goto err; 168 if (!EVP_MD_CTX_copy(&dctx->o_ctx, &sctx->o_ctx)) 169 goto err; 170 if (!EVP_MD_CTX_copy(&dctx->md_ctx, &sctx->md_ctx)) 171 goto err; 172 memcpy(dctx->key, sctx->key, HMAC_MAX_MD_CBLOCK); 173 dctx->key_length = sctx->key_length; 174 dctx->md = sctx->md; 175 return 1; 176 err: 177 return 0; 178 } 179 180 void HMAC_CTX_cleanup(HMAC_CTX *ctx) 181 { 182 EVP_MD_CTX_cleanup(&ctx->i_ctx); 183 EVP_MD_CTX_cleanup(&ctx->o_ctx); 184 EVP_MD_CTX_cleanup(&ctx->md_ctx); 185 memset(ctx,0,sizeof *ctx); 186 } 187 188 unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len, 189 const unsigned char *d, size_t n, unsigned char *md, 190 unsigned int *md_len) 191 { 192 HMAC_CTX c; 193 static unsigned char m[EVP_MAX_MD_SIZE]; 194 195 if (md == NULL) md=m; 196 HMAC_CTX_init(&c); 197 if (!HMAC_Init(&c,key,key_len,evp_md)) 198 goto err; 199 if (!HMAC_Update(&c,d,n)) 200 goto err; 201 if (!HMAC_Final(&c,md,md_len)) 202 goto err; 203 HMAC_CTX_cleanup(&c); 204 return md; 205 err: 206 return NULL; 207 } 208 209 void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags) 210 { 211 EVP_MD_CTX_set_flags(&ctx->i_ctx, flags); 212 EVP_MD_CTX_set_flags(&ctx->o_ctx, flags); 213 EVP_MD_CTX_set_flags(&ctx->md_ctx, flags); 214 } 215
