1 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
2 * project 1999.
3 */
4 /* ====================================================================
5 * Copyright (c) 1999 The OpenSSL Project. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 *
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 *
19 * 3. All advertising materials mentioning features or use of this
20 * software must display the following acknowledgment:
21 * "This product includes software developed by the OpenSSL Project
22 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
23 *
24 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
25 * endorse or promote products derived from this software without
26 * prior written permission. For written permission, please contact
27 * licensing@OpenSSL.org.
28 *
29 * 5. Products derived from this software may not be called "OpenSSL"
30 * nor may "OpenSSL" appear in their names without prior written
31 * permission of the OpenSSL Project.
32 *
33 * 6. Redistributions of any form whatsoever must retain the following
34 * acknowledgment:
35 * "This product includes software developed by the OpenSSL Project
36 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
37 *
38 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
39 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
41 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
42 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
47 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
48 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
49 * OF THE POSSIBILITY OF SUCH DAMAGE.
50 * ====================================================================
51 *
52 * This product includes cryptographic software written by Eric Young
53 * (eay@cryptsoft.com). This product includes software written by Tim
54 * Hudson (tjh@cryptsoft.com). */
55
56 #include <openssl/evp.h>
57
58 #include <string.h>
59
60 #include <openssl/hmac.h>
61
62
PKCS5_PBKDF2_HMAC(const char * password,size_t password_len,const uint8_t * salt,size_t salt_len,unsigned iterations,const EVP_MD * digest,size_t key_len,uint8_t * out_key)63 int PKCS5_PBKDF2_HMAC(const char *password, size_t password_len,
64 const uint8_t *salt, size_t salt_len, unsigned iterations,
65 const EVP_MD *digest, size_t key_len, uint8_t *out_key) {
66 uint8_t digest_tmp[EVP_MAX_MD_SIZE], *p, itmp[4];
67 size_t cplen, mdlen, tkeylen, k;
68 unsigned j;
69 uint32_t i = 1;
70 HMAC_CTX hctx_tpl, hctx;
71
72 mdlen = EVP_MD_size(digest);
73 HMAC_CTX_init(&hctx_tpl);
74 p = out_key;
75 tkeylen = key_len;
76 if (!HMAC_Init_ex(&hctx_tpl, password, password_len, digest, NULL)) {
77 HMAC_CTX_cleanup(&hctx_tpl);
78 return 0;
79 }
80 while (tkeylen) {
81 if (tkeylen > mdlen) {
82 cplen = mdlen;
83 } else {
84 cplen = tkeylen;
85 }
86 /* We are unlikely to ever use more than 256 blocks (5120 bits!)
87 * but just in case... */
88 itmp[0] = (uint8_t)((i >> 24) & 0xff);
89 itmp[1] = (uint8_t)((i >> 16) & 0xff);
90 itmp[2] = (uint8_t)((i >> 8) & 0xff);
91 itmp[3] = (uint8_t)(i & 0xff);
92 if (!HMAC_CTX_copy(&hctx, &hctx_tpl)) {
93 HMAC_CTX_cleanup(&hctx_tpl);
94 return 0;
95 }
96 if (!HMAC_Update(&hctx, salt, salt_len) ||
97 !HMAC_Update(&hctx, itmp, 4) ||
98 !HMAC_Final(&hctx, digest_tmp, NULL)) {
99 HMAC_CTX_cleanup(&hctx_tpl);
100 HMAC_CTX_cleanup(&hctx);
101 return 0;
102 }
103 HMAC_CTX_cleanup(&hctx);
104 memcpy(p, digest_tmp, cplen);
105 for (j = 1; j < iterations; j++) {
106 if (!HMAC_CTX_copy(&hctx, &hctx_tpl)) {
107 HMAC_CTX_cleanup(&hctx_tpl);
108 return 0;
109 }
110 if (!HMAC_Update(&hctx, digest_tmp, mdlen) ||
111 !HMAC_Final(&hctx, digest_tmp, NULL)) {
112 HMAC_CTX_cleanup(&hctx_tpl);
113 HMAC_CTX_cleanup(&hctx);
114 return 0;
115 }
116 HMAC_CTX_cleanup(&hctx);
117 for (k = 0; k < cplen; k++) {
118 p[k] ^= digest_tmp[k];
119 }
120 }
121 tkeylen -= cplen;
122 i++;
123 p += cplen;
124 }
125 HMAC_CTX_cleanup(&hctx_tpl);
126
127 // RFC 2898 describes iterations (c) as being a "positive integer", so a
128 // value of 0 is an error.
129 //
130 // Unfortunatley not all consumers of PKCS5_PBKDF2_HMAC() check their return
131 // value, expecting it to succeed and unconditonally using |out_key|.
132 // As a precaution for such callsites in external code, the old behavior
133 // of iterations < 1 being treated as iterations == 1 is preserved, but
134 // additionally an error result is returned.
135 //
136 // TODO(eroman): Figure out how to remove this compatibility hack, or change
137 // the default to something more sensible like 2048.
138 if (iterations == 0) {
139 return 0;
140 }
141
142 return 1;
143 }
144
PKCS5_PBKDF2_HMAC_SHA1(const char * password,size_t password_len,const uint8_t * salt,size_t salt_len,unsigned iterations,size_t key_len,uint8_t * out_key)145 int PKCS5_PBKDF2_HMAC_SHA1(const char *password, size_t password_len,
146 const uint8_t *salt, size_t salt_len,
147 unsigned iterations, size_t key_len,
148 uint8_t *out_key) {
149 return PKCS5_PBKDF2_HMAC(password, password_len, salt, salt_len, iterations,
150 EVP_sha1(), key_len, out_key);
151 }
152