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 64#ifdef OPENSSL_FIPS 65# include <openssl/fips.h> 66#endif 67 68int 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 switch to approved implementation if possible */ 76 if (FIPS_mode()) { 77 const EVP_MD *fipsmd; 78 if (md) { 79 fipsmd = FIPS_get_digestbynid(EVP_MD_type(md)); 80 if (fipsmd) 81 md = fipsmd; 82 } 83 } 84 85 if (FIPS_mode()) { 86 /* If we have an ENGINE need to allow non FIPS */ 87 if ((impl || ctx->i_ctx.engine) 88 && !(ctx->i_ctx.flags & EVP_CIPH_FLAG_NON_FIPS_ALLOW)) { 89 EVPerr(EVP_F_HMAC_INIT_EX, EVP_R_DISABLED_FOR_FIPS); 90 return 0; 91 } 92 /* 93 * Other algorithm blocking will be done in FIPS_cmac_init, via 94 * FIPS_hmac_init_ex(). 95 */ 96 if (!impl && !ctx->i_ctx.engine) 97 return FIPS_hmac_init_ex(ctx, key, len, md, NULL); 98 } 99#endif 100 /* If we are changing MD then we must have a key */ 101 if (md != NULL && md != ctx->md && (key == NULL || len < 0)) 102 return 0; 103 104 if (md != NULL) { 105 reset = 1; 106 ctx->md = md; 107 } else if (ctx->md) { 108 md = ctx->md; 109 } else { 110 return 0; 111 } 112 113 if (key != NULL) { 114 reset = 1; 115 j = EVP_MD_block_size(md); 116 OPENSSL_assert(j <= (int)sizeof(ctx->key)); 117 if (j < len) { 118 if (!EVP_DigestInit_ex(&ctx->md_ctx, md, impl)) 119 goto err; 120 if (!EVP_DigestUpdate(&ctx->md_ctx, key, len)) 121 goto err; 122 if (!EVP_DigestFinal_ex(&(ctx->md_ctx), ctx->key, 123 &ctx->key_length)) 124 goto err; 125 } else { 126 if (len < 0 || len > (int)sizeof(ctx->key)) 127 return 0; 128 memcpy(ctx->key, key, len); 129 ctx->key_length = len; 130 } 131 if (ctx->key_length != HMAC_MAX_MD_CBLOCK) 132 memset(&ctx->key[ctx->key_length], 0, 133 HMAC_MAX_MD_CBLOCK - ctx->key_length); 134 } 135 136 if (reset) { 137 for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) 138 pad[i] = 0x36 ^ ctx->key[i]; 139 if (!EVP_DigestInit_ex(&ctx->i_ctx, md, impl)) 140 goto err; 141 if (!EVP_DigestUpdate(&ctx->i_ctx, pad, EVP_MD_block_size(md))) 142 goto err; 143 144 for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) 145 pad[i] = 0x5c ^ ctx->key[i]; 146 if (!EVP_DigestInit_ex(&ctx->o_ctx, md, impl)) 147 goto err; 148 if (!EVP_DigestUpdate(&ctx->o_ctx, pad, EVP_MD_block_size(md))) 149 goto err; 150 } 151 if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->i_ctx)) 152 goto err; 153 return 1; 154 err: 155 return 0; 156} 157 158int HMAC_Init(HMAC_CTX *ctx, const void *key, int len, const EVP_MD *md) 159{ 160 if (key && md) 161 HMAC_CTX_init(ctx); 162 return HMAC_Init_ex(ctx, key, len, md, NULL); 163} 164 165int HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len) 166{ 167#ifdef OPENSSL_FIPS 168 if (FIPS_mode() && !ctx->i_ctx.engine) 169 return FIPS_hmac_update(ctx, data, len); 170#endif 171 if (!ctx->md) 172 return 0; 173 174 return EVP_DigestUpdate(&ctx->md_ctx, data, len); 175} 176 177int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len) 178{ 179 unsigned int i; 180 unsigned char buf[EVP_MAX_MD_SIZE]; 181#ifdef OPENSSL_FIPS 182 if (FIPS_mode() && !ctx->i_ctx.engine) 183 return FIPS_hmac_final(ctx, md, len); 184#endif 185 186 if (!ctx->md) 187 goto err; 188 189 if (!EVP_DigestFinal_ex(&ctx->md_ctx, buf, &i)) 190 goto err; 191 if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->o_ctx)) 192 goto err; 193 if (!EVP_DigestUpdate(&ctx->md_ctx, buf, i)) 194 goto err; 195 if (!EVP_DigestFinal_ex(&ctx->md_ctx, md, len)) 196 goto err; 197 return 1; 198 err: 199 return 0; 200} 201 202void HMAC_CTX_init(HMAC_CTX *ctx) 203{ 204 EVP_MD_CTX_init(&ctx->i_ctx); 205 EVP_MD_CTX_init(&ctx->o_ctx); 206 EVP_MD_CTX_init(&ctx->md_ctx); 207 ctx->md = NULL; 208} 209 210int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx) 211{ 212 if (!EVP_MD_CTX_copy(&dctx->i_ctx, &sctx->i_ctx)) 213 goto err; 214 if (!EVP_MD_CTX_copy(&dctx->o_ctx, &sctx->o_ctx)) 215 goto err; 216 if (!EVP_MD_CTX_copy(&dctx->md_ctx, &sctx->md_ctx)) 217 goto err; 218 memcpy(dctx->key, sctx->key, HMAC_MAX_MD_CBLOCK); 219 dctx->key_length = sctx->key_length; 220 dctx->md = sctx->md; 221 return 1; 222 err: 223 return 0; 224} 225 226void HMAC_CTX_cleanup(HMAC_CTX *ctx) 227{ 228#ifdef OPENSSL_FIPS 229 if (FIPS_mode() && !ctx->i_ctx.engine) { 230 FIPS_hmac_ctx_cleanup(ctx); 231 return; 232 } 233#endif 234 EVP_MD_CTX_cleanup(&ctx->i_ctx); 235 EVP_MD_CTX_cleanup(&ctx->o_ctx); 236 EVP_MD_CTX_cleanup(&ctx->md_ctx); 237 memset(ctx, 0, sizeof *ctx); 238} 239 240unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len, 241 const unsigned char *d, size_t n, unsigned char *md, 242 unsigned int *md_len) 243{ 244 HMAC_CTX c; 245 static unsigned char m[EVP_MAX_MD_SIZE]; 246 247 if (md == NULL) 248 md = m; 249 HMAC_CTX_init(&c); 250 if (!HMAC_Init(&c, key, key_len, evp_md)) 251 goto err; 252 if (!HMAC_Update(&c, d, n)) 253 goto err; 254 if (!HMAC_Final(&c, md, md_len)) 255 goto err; 256 HMAC_CTX_cleanup(&c); 257 return md; 258 err: 259 HMAC_CTX_cleanup(&c); 260 return NULL; 261} 262 263void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags) 264{ 265 EVP_MD_CTX_set_flags(&ctx->i_ctx, flags); 266 EVP_MD_CTX_set_flags(&ctx->o_ctx, flags); 267 EVP_MD_CTX_set_flags(&ctx->md_ctx, flags); 268} 269