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      1 /* p5_crpt2.c */
      2 /* Written by Dr Stephen N Henson (steve (at) openssl.org) for the OpenSSL
      3  * project 1999.
      4  */
      5 /* ====================================================================
      6  * Copyright (c) 1999-2006 The OpenSSL Project.  All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  *
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  *
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in
     17  *    the documentation and/or other materials provided with the
     18  *    distribution.
     19  *
     20  * 3. All advertising materials mentioning features or use of this
     21  *    software must display the following acknowledgment:
     22  *    "This product includes software developed by the OpenSSL Project
     23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
     24  *
     25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
     26  *    endorse or promote products derived from this software without
     27  *    prior written permission. For written permission, please contact
     28  *    licensing (at) OpenSSL.org.
     29  *
     30  * 5. Products derived from this software may not be called "OpenSSL"
     31  *    nor may "OpenSSL" appear in their names without prior written
     32  *    permission of the OpenSSL Project.
     33  *
     34  * 6. Redistributions of any form whatsoever must retain the following
     35  *    acknowledgment:
     36  *    "This product includes software developed by the OpenSSL Project
     37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
     38  *
     39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
     40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
     43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
     50  * OF THE POSSIBILITY OF SUCH DAMAGE.
     51  * ====================================================================
     52  *
     53  * This product includes cryptographic software written by Eric Young
     54  * (eay (at) cryptsoft.com).  This product includes software written by Tim
     55  * Hudson (tjh (at) cryptsoft.com).
     56  *
     57  */
     58 #include <stdio.h>
     59 #include <stdlib.h>
     60 #include "cryptlib.h"
     61 #if !defined(OPENSSL_NO_HMAC) && !defined(OPENSSL_NO_SHA)
     62 #include <openssl/x509.h>
     63 #include <openssl/evp.h>
     64 #include <openssl/hmac.h>
     65 #include "evp_locl.h"
     66 
     67 /* set this to print out info about the keygen algorithm */
     68 /* #define DEBUG_PKCS5V2 */
     69 
     70 #ifdef DEBUG_PKCS5V2
     71 	static void h__dump (const unsigned char *p, int len);
     72 #endif
     73 
     74 /* This is an implementation of PKCS#5 v2.0 password based encryption key
     75  * derivation function PBKDF2.
     76  * SHA1 version verified against test vectors posted by Peter Gutmann
     77  * <pgut001 (at) cs.auckland.ac.nz> to the PKCS-TNG <pkcs-tng (at) rsa.com> mailing list.
     78  */
     79 
     80 int PKCS5_PBKDF2_HMAC(const char *pass, int passlen,
     81 			   const unsigned char *salt, int saltlen, int iter,
     82 			   const EVP_MD *digest,
     83 			   int keylen, unsigned char *out)
     84 	{
     85 	unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
     86 	int cplen, j, k, tkeylen, mdlen;
     87 	unsigned long i = 1;
     88 	HMAC_CTX hctx_tpl, hctx;
     89 
     90 	mdlen = EVP_MD_size(digest);
     91 	if (mdlen < 0)
     92 		return 0;
     93 
     94 	HMAC_CTX_init(&hctx_tpl);
     95 	p = out;
     96 	tkeylen = keylen;
     97 	if(!pass)
     98 		passlen = 0;
     99 	else if(passlen == -1)
    100 		passlen = strlen(pass);
    101 	if (!HMAC_Init_ex(&hctx_tpl, pass, passlen, digest, NULL))
    102 		{
    103 		HMAC_CTX_cleanup(&hctx_tpl);
    104 		return 0;
    105 		}
    106 	while(tkeylen)
    107 		{
    108 		if(tkeylen > mdlen)
    109 			cplen = mdlen;
    110 		else
    111 			cplen = tkeylen;
    112 		/* We are unlikely to ever use more than 256 blocks (5120 bits!)
    113 		 * but just in case...
    114 		 */
    115 		itmp[0] = (unsigned char)((i >> 24) & 0xff);
    116 		itmp[1] = (unsigned char)((i >> 16) & 0xff);
    117 		itmp[2] = (unsigned char)((i >> 8) & 0xff);
    118 		itmp[3] = (unsigned char)(i & 0xff);
    119 		if (!HMAC_CTX_copy(&hctx, &hctx_tpl))
    120 			{
    121 			HMAC_CTX_cleanup(&hctx_tpl);
    122 			return 0;
    123 			}
    124 		if (!HMAC_Update(&hctx, salt, saltlen)
    125 		    || !HMAC_Update(&hctx, itmp, 4)
    126 		    || !HMAC_Final(&hctx, digtmp, NULL))
    127 			{
    128 			HMAC_CTX_cleanup(&hctx_tpl);
    129 			HMAC_CTX_cleanup(&hctx);
    130 			return 0;
    131 			}
    132 		HMAC_CTX_cleanup(&hctx);
    133 		memcpy(p, digtmp, cplen);
    134 		for(j = 1; j < iter; j++)
    135 			{
    136 			if (!HMAC_CTX_copy(&hctx, &hctx_tpl))
    137 				{
    138 				HMAC_CTX_cleanup(&hctx_tpl);
    139 				return 0;
    140 				}
    141 			if (!HMAC_Update(&hctx, digtmp, mdlen)
    142 			    || !HMAC_Final(&hctx, digtmp, NULL))
    143 				{
    144 				HMAC_CTX_cleanup(&hctx_tpl);
    145 				HMAC_CTX_cleanup(&hctx);
    146 				return 0;
    147 				}
    148 			HMAC_CTX_cleanup(&hctx);
    149 			for(k = 0; k < cplen; k++)
    150 				p[k] ^= digtmp[k];
    151 			}
    152 		tkeylen-= cplen;
    153 		i++;
    154 		p+= cplen;
    155 		}
    156 	HMAC_CTX_cleanup(&hctx_tpl);
    157 #ifdef DEBUG_PKCS5V2
    158 	fprintf(stderr, "Password:\n");
    159 	h__dump (pass, passlen);
    160 	fprintf(stderr, "Salt:\n");
    161 	h__dump (salt, saltlen);
    162 	fprintf(stderr, "Iteration count %d\n", iter);
    163 	fprintf(stderr, "Key:\n");
    164 	h__dump (out, keylen);
    165 #endif
    166 	return 1;
    167 	}
    168 
    169 int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen,
    170 			   const unsigned char *salt, int saltlen, int iter,
    171 			   int keylen, unsigned char *out)
    172 	{
    173 	return PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, EVP_sha1(),
    174 					keylen, out);
    175 	}
    176 
    177 #ifdef DO_TEST
    178 main()
    179 {
    180 	unsigned char out[4];
    181 	unsigned char salt[] = {0x12, 0x34, 0x56, 0x78};
    182 	PKCS5_PBKDF2_HMAC_SHA1("password", -1, salt, 4, 5, 4, out);
    183 	fprintf(stderr, "Out %02X %02X %02X %02X\n",
    184 					 out[0], out[1], out[2], out[3]);
    185 }
    186 
    187 #endif
    188 
    189 /* Now the key derivation function itself. This is a bit evil because
    190  * it has to check the ASN1 parameters are valid: and there are quite a
    191  * few of them...
    192  */
    193 
    194 int PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,
    195                          ASN1_TYPE *param, const EVP_CIPHER *c, const EVP_MD *md,
    196                          int en_de)
    197 {
    198 	const unsigned char *pbuf;
    199 	int plen;
    200 	PBE2PARAM *pbe2 = NULL;
    201 	const EVP_CIPHER *cipher;
    202 
    203 	int rv = 0;
    204 
    205 	if (param == NULL || param->type != V_ASN1_SEQUENCE ||
    206 	    param->value.sequence == NULL) {
    207 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
    208 		goto err;
    209 	}
    210 
    211 	pbuf = param->value.sequence->data;
    212 	plen = param->value.sequence->length;
    213 	if(!(pbe2 = d2i_PBE2PARAM(NULL, &pbuf, plen))) {
    214 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
    215 		goto err;
    216 	}
    217 
    218 	/* See if we recognise the key derivation function */
    219 
    220 	if(OBJ_obj2nid(pbe2->keyfunc->algorithm) != NID_id_pbkdf2) {
    221 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
    222 				EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);
    223 		goto err;
    224 	}
    225 
    226 	/* lets see if we recognise the encryption algorithm.
    227 	 */
    228 
    229 	cipher = EVP_get_cipherbyobj(pbe2->encryption->algorithm);
    230 
    231 	if(!cipher) {
    232 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
    233 						EVP_R_UNSUPPORTED_CIPHER);
    234 		goto err;
    235 	}
    236 
    237 	/* Fixup cipher based on AlgorithmIdentifier */
    238 	if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, en_de))
    239 		goto err;
    240 	if(EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) < 0) {
    241 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
    242 					EVP_R_CIPHER_PARAMETER_ERROR);
    243 		goto err;
    244 	}
    245 	rv = PKCS5_v2_PBKDF2_keyivgen(ctx, pass, passlen,
    246 					pbe2->keyfunc->parameter, c, md, en_de);
    247 	err:
    248 	PBE2PARAM_free(pbe2);
    249 	return rv;
    250 }
    251 
    252 int PKCS5_v2_PBKDF2_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,
    253                          ASN1_TYPE *param,
    254 			 const EVP_CIPHER *c, const EVP_MD *md, int en_de)
    255 {
    256 	unsigned char *salt, key[EVP_MAX_KEY_LENGTH];
    257 	const unsigned char *pbuf;
    258 	int saltlen, iter, plen;
    259 	int rv = 0;
    260 	unsigned int keylen = 0;
    261 	int prf_nid, hmac_md_nid;
    262 	PBKDF2PARAM *kdf = NULL;
    263 	const EVP_MD *prfmd;
    264 
    265 	if (EVP_CIPHER_CTX_cipher(ctx) == NULL)
    266 		{
    267 		EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN,EVP_R_NO_CIPHER_SET);
    268 		goto err;
    269 		}
    270 	keylen = EVP_CIPHER_CTX_key_length(ctx);
    271 	OPENSSL_assert(keylen <= sizeof key);
    272 
    273 	/* Decode parameter */
    274 
    275 	if(!param || (param->type != V_ASN1_SEQUENCE))
    276 		{
    277 		EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN,EVP_R_DECODE_ERROR);
    278 		goto err;
    279 		}
    280 
    281 	pbuf = param->value.sequence->data;
    282 	plen = param->value.sequence->length;
    283 
    284 	if(!(kdf = d2i_PBKDF2PARAM(NULL, &pbuf, plen)) ) {
    285 		EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN,EVP_R_DECODE_ERROR);
    286 		goto err;
    287 	}
    288 
    289 	keylen = EVP_CIPHER_CTX_key_length(ctx);
    290 
    291 	/* Now check the parameters of the kdf */
    292 
    293 	if(kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != (int)keylen)){
    294 		EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN,
    295 						EVP_R_UNSUPPORTED_KEYLENGTH);
    296 		goto err;
    297 	}
    298 
    299 	if (kdf->prf)
    300 		prf_nid = OBJ_obj2nid(kdf->prf->algorithm);
    301 	else
    302 		prf_nid = NID_hmacWithSHA1;
    303 
    304 	if (!EVP_PBE_find(EVP_PBE_TYPE_PRF, prf_nid, NULL, &hmac_md_nid, 0))
    305 		{
    306 		EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
    307 		goto err;
    308 		}
    309 
    310 	prfmd = EVP_get_digestbynid(hmac_md_nid);
    311 	if (prfmd == NULL)
    312 		{
    313 		EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
    314 		goto err;
    315 		}
    316 
    317 	if(kdf->salt->type != V_ASN1_OCTET_STRING) {
    318 		EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN,
    319 						EVP_R_UNSUPPORTED_SALT_TYPE);
    320 		goto err;
    321 	}
    322 
    323 	/* it seems that its all OK */
    324 	salt = kdf->salt->value.octet_string->data;
    325 	saltlen = kdf->salt->value.octet_string->length;
    326 	iter = ASN1_INTEGER_get(kdf->iter);
    327 	if(!PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, prfmd,
    328 						   keylen, key))
    329 		goto err;
    330 	rv = EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);
    331 	err:
    332 	OPENSSL_cleanse(key, keylen);
    333 	PBKDF2PARAM_free(kdf);
    334 	return rv;
    335 }
    336 
    337 #ifdef DEBUG_PKCS5V2
    338 static void h__dump (const unsigned char *p, int len)
    339 {
    340         for (; len --; p++) fprintf(stderr, "%02X ", *p);
    341         fprintf(stderr, "\n");
    342 }
    343 #endif
    344 #endif
    345