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1 /* p5_crpt2.c */
2 /* Written by Dr Stephen N Henson (steve@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@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@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@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 
66 /* set this to print out info about the keygen algorithm */
67 /* #define DEBUG_PKCS5V2 */
68 
69 #ifdef DEBUG_PKCS5V2
70 	static void h__dump (const unsigned char *p, int len);
71 #endif
72 
73 /* This is an implementation of PKCS#5 v2.0 password based encryption key
74  * derivation function PBKDF2.
75  * SHA1 version verified against test vectors posted by Peter Gutmann
76  * <pgut001@cs.auckland.ac.nz> to the PKCS-TNG <pkcs-tng@rsa.com> mailing list.
77  */
78 
PKCS5_PBKDF2_HMAC(const char * pass,int passlen,const unsigned char * salt,int saltlen,int iter,const EVP_MD * digest,int keylen,unsigned char * out)79 int PKCS5_PBKDF2_HMAC(const char *pass, int passlen,
80 			   const unsigned char *salt, int saltlen, int iter,
81 			   const EVP_MD *digest,
82 			   int keylen, unsigned char *out)
83 	{
84 	unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
85 	int cplen, j, k, tkeylen, mdlen;
86 	unsigned long i = 1;
87 	HMAC_CTX hctx;
88 
89 	mdlen = EVP_MD_size(digest);
90 	if (mdlen < 0)
91 		return 0;
92 
93 	HMAC_CTX_init(&hctx);
94 	p = out;
95 	tkeylen = keylen;
96 	if(!pass)
97 		passlen = 0;
98 	else if(passlen == -1)
99 		passlen = strlen(pass);
100 	while(tkeylen)
101 		{
102 		if(tkeylen > mdlen)
103 			cplen = mdlen;
104 		else
105 			cplen = tkeylen;
106 		/* We are unlikely to ever use more than 256 blocks (5120 bits!)
107 		 * but just in case...
108 		 */
109 		itmp[0] = (unsigned char)((i >> 24) & 0xff);
110 		itmp[1] = (unsigned char)((i >> 16) & 0xff);
111 		itmp[2] = (unsigned char)((i >> 8) & 0xff);
112 		itmp[3] = (unsigned char)(i & 0xff);
113 		HMAC_Init_ex(&hctx, pass, passlen, digest, NULL);
114 		HMAC_Update(&hctx, salt, saltlen);
115 		HMAC_Update(&hctx, itmp, 4);
116 		HMAC_Final(&hctx, digtmp, NULL);
117 		memcpy(p, digtmp, cplen);
118 		for(j = 1; j < iter; j++)
119 			{
120 			HMAC(digest, pass, passlen,
121 				 digtmp, mdlen, digtmp, NULL);
122 			for(k = 0; k < cplen; k++)
123 				p[k] ^= digtmp[k];
124 			}
125 		tkeylen-= cplen;
126 		i++;
127 		p+= cplen;
128 		}
129 	HMAC_CTX_cleanup(&hctx);
130 #ifdef DEBUG_PKCS5V2
131 	fprintf(stderr, "Password:\n");
132 	h__dump (pass, passlen);
133 	fprintf(stderr, "Salt:\n");
134 	h__dump (salt, saltlen);
135 	fprintf(stderr, "Iteration count %d\n", iter);
136 	fprintf(stderr, "Key:\n");
137 	h__dump (out, keylen);
138 #endif
139 	return 1;
140 	}
141 
PKCS5_PBKDF2_HMAC_SHA1(const char * pass,int passlen,const unsigned char * salt,int saltlen,int iter,int keylen,unsigned char * out)142 int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen,
143 			   const unsigned char *salt, int saltlen, int iter,
144 			   int keylen, unsigned char *out)
145 	{
146 	return PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, EVP_sha1(),
147 					keylen, out);
148 	}
149 
150 #ifdef DO_TEST
main()151 main()
152 {
153 	unsigned char out[4];
154 	unsigned char salt[] = {0x12, 0x34, 0x56, 0x78};
155 	PKCS5_PBKDF2_HMAC_SHA1("password", -1, salt, 4, 5, 4, out);
156 	fprintf(stderr, "Out %02X %02X %02X %02X\n",
157 					 out[0], out[1], out[2], out[3]);
158 }
159 
160 #endif
161 
162 /* Now the key derivation function itself. This is a bit evil because
163  * it has to check the ASN1 parameters are valid: and there are quite a
164  * few of them...
165  */
166 
PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX * ctx,const char * pass,int passlen,ASN1_TYPE * param,const EVP_CIPHER * c,const EVP_MD * md,int en_de)167 int PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,
168                          ASN1_TYPE *param, const EVP_CIPHER *c, const EVP_MD *md,
169                          int en_de)
170 {
171 	unsigned char *salt, key[EVP_MAX_KEY_LENGTH];
172 	const unsigned char *pbuf;
173 	int saltlen, iter, plen;
174 	unsigned int keylen;
175 	PBE2PARAM *pbe2 = NULL;
176 	const EVP_CIPHER *cipher;
177 	PBKDF2PARAM *kdf = NULL;
178 	const EVP_MD *prfmd;
179 	int prf_nid, hmac_md_nid;
180 
181 	if (param == NULL || param->type != V_ASN1_SEQUENCE ||
182 	    param->value.sequence == NULL) {
183 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
184 		return 0;
185 	}
186 
187 	pbuf = param->value.sequence->data;
188 	plen = param->value.sequence->length;
189 	if(!(pbe2 = d2i_PBE2PARAM(NULL, &pbuf, plen))) {
190 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
191 		return 0;
192 	}
193 
194 	/* See if we recognise the key derivation function */
195 
196 	if(OBJ_obj2nid(pbe2->keyfunc->algorithm) != NID_id_pbkdf2) {
197 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
198 				EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);
199 		goto err;
200 	}
201 
202 	/* lets see if we recognise the encryption algorithm.
203 	 */
204 
205 	cipher = EVP_get_cipherbyobj(pbe2->encryption->algorithm);
206 
207 	if(!cipher) {
208 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
209 						EVP_R_UNSUPPORTED_CIPHER);
210 		goto err;
211 	}
212 
213 	/* Fixup cipher based on AlgorithmIdentifier */
214 	EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, en_de);
215 	if(EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) < 0) {
216 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
217 					EVP_R_CIPHER_PARAMETER_ERROR);
218 		goto err;
219 	}
220 	keylen = EVP_CIPHER_CTX_key_length(ctx);
221 	OPENSSL_assert(keylen <= sizeof key);
222 
223 	/* Now decode key derivation function */
224 
225 	if(!pbe2->keyfunc->parameter ||
226 		 (pbe2->keyfunc->parameter->type != V_ASN1_SEQUENCE))
227 		{
228 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
229 		goto err;
230 		}
231 
232 	pbuf = pbe2->keyfunc->parameter->value.sequence->data;
233 	plen = pbe2->keyfunc->parameter->value.sequence->length;
234 	if(!(kdf = d2i_PBKDF2PARAM(NULL, &pbuf, plen)) ) {
235 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
236 		goto err;
237 	}
238 
239 	PBE2PARAM_free(pbe2);
240 	pbe2 = NULL;
241 
242 	/* Now check the parameters of the kdf */
243 
244 	if(kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != (int)keylen)){
245 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
246 						EVP_R_UNSUPPORTED_KEYLENGTH);
247 		goto err;
248 	}
249 
250 	if (kdf->prf)
251 		prf_nid = OBJ_obj2nid(kdf->prf->algorithm);
252 	else
253 		prf_nid = NID_hmacWithSHA1;
254 
255 	if (!EVP_PBE_find(EVP_PBE_TYPE_PRF, prf_nid, NULL, &hmac_md_nid, 0))
256 		{
257 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
258 		goto err;
259 		}
260 
261 	prfmd = EVP_get_digestbynid(hmac_md_nid);
262 	if (prfmd == NULL)
263 		{
264 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
265 		goto err;
266 		}
267 
268 	if(kdf->salt->type != V_ASN1_OCTET_STRING) {
269 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
270 						EVP_R_UNSUPPORTED_SALT_TYPE);
271 		goto err;
272 	}
273 
274 	/* it seems that its all OK */
275 	salt = kdf->salt->value.octet_string->data;
276 	saltlen = kdf->salt->value.octet_string->length;
277 	iter = ASN1_INTEGER_get(kdf->iter);
278 	if(!PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, prfmd,
279 						   keylen, key))
280 		goto err;
281 	EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);
282 	OPENSSL_cleanse(key, keylen);
283 	PBKDF2PARAM_free(kdf);
284 	return 1;
285 
286 	err:
287 	PBE2PARAM_free(pbe2);
288 	PBKDF2PARAM_free(kdf);
289 	return 0;
290 }
291 
292 #ifdef DEBUG_PKCS5V2
h__dump(const unsigned char * p,int len)293 static void h__dump (const unsigned char *p, int len)
294 {
295         for (; len --; p++) fprintf(stderr, "%02X ", *p);
296         fprintf(stderr, "\n");
297 }
298 #endif
299 #endif
300