1 /* p5_crpt2.c */
2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
3  * project 1999.
4  */
5 /* ====================================================================
6  * Copyright (c) 1999 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 #if !defined(OPENSSL_NO_HMAC) && !defined(OPENSSL_NO_SHA)
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include "cryptlib.h"
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 using the only currently defined function HMAC
75  * with SHA1. 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_SHA1(const char * pass,int passlen,unsigned char * salt,int saltlen,int iter,int keylen,unsigned char * out)79 int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen,
80 			   unsigned char *salt, int saltlen, int iter,
81 			   int keylen, unsigned char *out)
82 {
83 	unsigned char digtmp[SHA_DIGEST_LENGTH], *p, itmp[4];
84 	int cplen, j, k, tkeylen;
85 	unsigned long i = 1;
86 	HMAC_CTX hctx;
87 
88 	HMAC_CTX_init(&hctx);
89 	p = out;
90 	tkeylen = keylen;
91 	if(!pass) passlen = 0;
92 	else if(passlen == -1) passlen = strlen(pass);
93 	while(tkeylen) {
94 		if(tkeylen > SHA_DIGEST_LENGTH) cplen = SHA_DIGEST_LENGTH;
95 		else cplen = tkeylen;
96 		/* We are unlikely to ever use more than 256 blocks (5120 bits!)
97 		 * but just in case...
98 		 */
99 		itmp[0] = (unsigned char)((i >> 24) & 0xff);
100 		itmp[1] = (unsigned char)((i >> 16) & 0xff);
101 		itmp[2] = (unsigned char)((i >> 8) & 0xff);
102 		itmp[3] = (unsigned char)(i & 0xff);
103 		HMAC_Init_ex(&hctx, pass, passlen, EVP_sha1(), NULL);
104 		HMAC_Update(&hctx, salt, saltlen);
105 		HMAC_Update(&hctx, itmp, 4);
106 		HMAC_Final(&hctx, digtmp, NULL);
107 		memcpy(p, digtmp, cplen);
108 		for(j = 1; j < iter; j++) {
109 			HMAC(EVP_sha1(), pass, passlen,
110 				 digtmp, SHA_DIGEST_LENGTH, digtmp, NULL);
111 			for(k = 0; k < cplen; k++) p[k] ^= digtmp[k];
112 		}
113 		tkeylen-= cplen;
114 		i++;
115 		p+= cplen;
116 	}
117 	HMAC_CTX_cleanup(&hctx);
118 #ifdef DEBUG_PKCS5V2
119 	fprintf(stderr, "Password:\n");
120 	h__dump (pass, passlen);
121 	fprintf(stderr, "Salt:\n");
122 	h__dump (salt, saltlen);
123 	fprintf(stderr, "Iteration count %d\n", iter);
124 	fprintf(stderr, "Key:\n");
125 	h__dump (out, keylen);
126 #endif
127 	return 1;
128 }
129 
130 #ifdef DO_TEST
main()131 main()
132 {
133 	unsigned char out[4];
134 	unsigned char salt[] = {0x12, 0x34, 0x56, 0x78};
135 	PKCS5_PBKDF2_HMAC_SHA1("password", -1, salt, 4, 5, 4, out);
136 	fprintf(stderr, "Out %02X %02X %02X %02X\n",
137 					 out[0], out[1], out[2], out[3]);
138 }
139 
140 #endif
141 
142 /* Now the key derivation function itself. This is a bit evil because
143  * it has to check the ASN1 parameters are valid: and there are quite a
144  * few of them...
145  */
146 
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)147 int PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,
148                          ASN1_TYPE *param, const EVP_CIPHER *c, const EVP_MD *md,
149                          int en_de)
150 {
151 	unsigned char *pbuf, *salt, key[EVP_MAX_KEY_LENGTH];
152 	int saltlen, keylen, iter, plen;
153 	PBE2PARAM *pbe2 = NULL;
154 	const EVP_CIPHER *cipher;
155 	PBKDF2PARAM *kdf = NULL;
156 
157 	pbuf = param->value.sequence->data;
158 	plen = param->value.sequence->length;
159 	if(!param || (param->type != V_ASN1_SEQUENCE) ||
160 				   !(pbe2 = d2i_PBE2PARAM(NULL, &pbuf, plen))) {
161 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
162 		return 0;
163 	}
164 
165 	/* See if we recognise the key derivation function */
166 
167 	if(OBJ_obj2nid(pbe2->keyfunc->algorithm) != NID_id_pbkdf2) {
168 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
169 				EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);
170 		goto err;
171 	}
172 
173 	/* lets see if we recognise the encryption algorithm.
174 	 */
175 
176 	cipher = EVP_get_cipherbyname(
177 			OBJ_nid2sn(OBJ_obj2nid(pbe2->encryption->algorithm)));
178 
179 	if(!cipher) {
180 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
181 						EVP_R_UNSUPPORTED_CIPHER);
182 		goto err;
183 	}
184 
185 	/* Fixup cipher based on AlgorithmIdentifier */
186 	EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, en_de);
187 	if(EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) < 0) {
188 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
189 					EVP_R_CIPHER_PARAMETER_ERROR);
190 		goto err;
191 	}
192 	keylen = EVP_CIPHER_CTX_key_length(ctx);
193 	OPENSSL_assert(keylen <= sizeof key);
194 
195 	/* Now decode key derivation function */
196 
197 	if(!pbe2->keyfunc->parameter ||
198 		 (pbe2->keyfunc->parameter->type != V_ASN1_SEQUENCE))
199 		{
200 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
201 		goto err;
202 		}
203 
204 	pbuf = pbe2->keyfunc->parameter->value.sequence->data;
205 	plen = pbe2->keyfunc->parameter->value.sequence->length;
206 	if(!(kdf = d2i_PBKDF2PARAM(NULL, &pbuf, plen)) ) {
207 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,EVP_R_DECODE_ERROR);
208 		goto err;
209 	}
210 
211 	PBE2PARAM_free(pbe2);
212 	pbe2 = NULL;
213 
214 	/* Now check the parameters of the kdf */
215 
216 	if(kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != keylen)){
217 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
218 						EVP_R_UNSUPPORTED_KEYLENGTH);
219 		goto err;
220 	}
221 
222 	if(kdf->prf && (OBJ_obj2nid(kdf->prf->algorithm) != NID_hmacWithSHA1)) {
223 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
224 		goto err;
225 	}
226 
227 	if(kdf->salt->type != V_ASN1_OCTET_STRING) {
228 		EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
229 						EVP_R_UNSUPPORTED_SALT_TYPE);
230 		goto err;
231 	}
232 
233 	/* it seems that its all OK */
234 	salt = kdf->salt->value.octet_string->data;
235 	saltlen = kdf->salt->value.octet_string->length;
236 	iter = ASN1_INTEGER_get(kdf->iter);
237 	PKCS5_PBKDF2_HMAC_SHA1(pass, passlen, salt, saltlen, iter, keylen, key);
238 	EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);
239 	OPENSSL_cleanse(key, keylen);
240 	PBKDF2PARAM_free(kdf);
241 	return 1;
242 
243 	err:
244 	PBE2PARAM_free(pbe2);
245 	PBKDF2PARAM_free(kdf);
246 	return 0;
247 }
248 
249 #ifdef DEBUG_PKCS5V2
h__dump(const unsigned char * p,int len)250 static void h__dump (const unsigned char *p, int len)
251 {
252         for (; len --; p++) fprintf(stderr, "%02X ", *p);
253         fprintf(stderr, "\n");
254 }
255 #endif
256 #endif
257