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 <openssl/hmac.h> 62 63 void HMAC_Init(HMAC_CTX *ctx, const void *key, int len, 64 const EVP_MD *md) 65 { 66 int i,j,reset=0; 67 unsigned char pad[HMAC_MAX_MD_CBLOCK]; 68 69 if (md != NULL) 70 { 71 reset=1; 72 ctx->md=md; 73 } 74 else 75 md=ctx->md; 76 77 if (key != NULL) 78 { 79 reset=1; 80 j=EVP_MD_block_size(md); 81 if (j < len) 82 { 83 EVP_DigestInit(&ctx->md_ctx,md); 84 EVP_DigestUpdate(&ctx->md_ctx,key,len); 85 EVP_DigestFinal(&(ctx->md_ctx),ctx->key, 86 &ctx->key_length); 87 } 88 else 89 { 90 memcpy(ctx->key,key,len); 91 ctx->key_length=len; 92 } 93 if(ctx->key_length != HMAC_MAX_MD_CBLOCK) 94 memset(&ctx->key[ctx->key_length], 0, 95 HMAC_MAX_MD_CBLOCK - ctx->key_length); 96 } 97 98 if (reset) 99 { 100 for (i=0; i<HMAC_MAX_MD_CBLOCK; i++) 101 pad[i]=0x36^ctx->key[i]; 102 EVP_DigestInit(&ctx->i_ctx,md); 103 EVP_DigestUpdate(&ctx->i_ctx,pad,EVP_MD_block_size(md)); 104 105 for (i=0; i<HMAC_MAX_MD_CBLOCK; i++) 106 pad[i]=0x5c^ctx->key[i]; 107 EVP_DigestInit(&ctx->o_ctx,md); 108 EVP_DigestUpdate(&ctx->o_ctx,pad,EVP_MD_block_size(md)); 109 } 110 111 memcpy(&ctx->md_ctx,&ctx->i_ctx,sizeof(ctx->i_ctx)); 112 } 113 114 void HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, int len) 115 { 116 EVP_DigestUpdate(&(ctx->md_ctx),data,len); 117 } 118 119 void HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len) 120 { 121 int j; 122 unsigned int i; 123 unsigned char buf[EVP_MAX_MD_SIZE]; 124 125 j=EVP_MD_block_size(ctx->md); 126 127 EVP_DigestFinal(&(ctx->md_ctx),buf,&i); 128 memcpy(&(ctx->md_ctx),&(ctx->o_ctx),sizeof(ctx->o_ctx)); 129 EVP_DigestUpdate(&(ctx->md_ctx),buf,i); 130 EVP_DigestFinal(&(ctx->md_ctx),md,len); 131 } 132 133 void HMAC_cleanup(HMAC_CTX *ctx) 134 { 135 memset(ctx,0,sizeof(HMAC_CTX)); 136 } 137 138 unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len, 139 const unsigned char *d, int n, unsigned char *md, 140 unsigned int *md_len) 141 { 142 HMAC_CTX c; 143 static unsigned char m[EVP_MAX_MD_SIZE]; 144 145 if (md == NULL) md=m; 146 HMAC_Init(&c,key,key_len,evp_md); 147 HMAC_Update(&c,d,n); 148 HMAC_Final(&c,md,md_len); 149 HMAC_cleanup(&c); 150 return(md); 151 } 152 153