p5_crpt2.c revision 331638 
1/* p5_crpt2.c */
2/*
3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
4 * 1999.
5 */
6/* ====================================================================
7 * Copyright (c) 1999-2006 The OpenSSL Project.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in
18 *    the documentation and/or other materials provided with the
19 *    distribution.
20 *
21 * 3. All advertising materials mentioning features or use of this
22 *    software must display the following acknowledgment:
23 *    "This product includes software developed by the OpenSSL Project
24 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 *
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 *    endorse or promote products derived from this software without
28 *    prior written permission. For written permission, please contact
29 *    licensing@OpenSSL.org.
30 *
31 * 5. Products derived from this software may not be called "OpenSSL"
32 *    nor may "OpenSSL" appear in their names without prior written
33 *    permission of the OpenSSL Project.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 *    acknowledgment:
37 *    "This product includes software developed by the OpenSSL Project
38 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
53 *
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com).  This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
57 *
58 */
59#include <stdio.h>
60#include <stdlib.h>
61#include "cryptlib.h"
62#if !defined(OPENSSL_NO_HMAC) && !defined(OPENSSL_NO_SHA)
63# include <openssl/x509.h>
64# include <openssl/evp.h>
65# include <openssl/hmac.h>
66# include "evp_locl.h"
67
68/* set this to print out info about the keygen algorithm */
69/* #define DEBUG_PKCS5V2 */
70
71# ifdef DEBUG_PKCS5V2
72static void h__dump(const unsigned char *p, int len);
73# endif
74
75/*
76 * This is an implementation of PKCS#5 v2.0 password based encryption key
77 * derivation function PBKDF2. SHA1 version verified against test vectors
78 * posted by Peter Gutmann <pgut001@cs.auckland.ac.nz> to the PKCS-TNG
79 * <pkcs-tng@rsa.com> mailing list.
80 */
81
82int PKCS5_PBKDF2_HMAC(const char *pass, int passlen,
83                      const unsigned char *salt, int saltlen, int iter,
84                      const EVP_MD *digest, int keylen, unsigned char *out)
85{
86    unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
87    int cplen, j, k, tkeylen, mdlen;
88    unsigned long i = 1;
89    HMAC_CTX hctx_tpl, hctx;
90
91    mdlen = EVP_MD_size(digest);
92    if (mdlen < 0)
93        return 0;
94
95    HMAC_CTX_init(&hctx_tpl);
96    p = out;
97    tkeylen = keylen;
98    if (!pass)
99        passlen = 0;
100    else if (passlen == -1)
101        passlen = strlen(pass);
102    if (!HMAC_Init_ex(&hctx_tpl, pass, passlen, digest, NULL)) {
103        HMAC_CTX_cleanup(&hctx_tpl);
104        return 0;
105    }
106    while (tkeylen) {
107        if (tkeylen > mdlen)
108            cplen = mdlen;
109        else
110            cplen = tkeylen;
111        /*
112         * We are unlikely to ever use more than 256 blocks (5120 bits!) but
113         * 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            HMAC_CTX_cleanup(&hctx_tpl);
121            return 0;
122        }
123        if (!HMAC_Update(&hctx, salt, saltlen)
124            || !HMAC_Update(&hctx, itmp, 4)
125            || !HMAC_Final(&hctx, digtmp, NULL)) {
126            HMAC_CTX_cleanup(&hctx_tpl);
127            HMAC_CTX_cleanup(&hctx);
128            return 0;
129        }
130        HMAC_CTX_cleanup(&hctx);
131        memcpy(p, digtmp, cplen);
132        for (j = 1; j < iter; j++) {
133            if (!HMAC_CTX_copy(&hctx, &hctx_tpl)) {
134                HMAC_CTX_cleanup(&hctx_tpl);
135                return 0;
136            }
137            if (!HMAC_Update(&hctx, digtmp, mdlen)
138                || !HMAC_Final(&hctx, digtmp, NULL)) {
139                HMAC_CTX_cleanup(&hctx_tpl);
140                HMAC_CTX_cleanup(&hctx);
141                return 0;
142            }
143            HMAC_CTX_cleanup(&hctx);
144            for (k = 0; k < cplen; k++)
145                p[k] ^= digtmp[k];
146        }
147        tkeylen -= cplen;
148        i++;
149        p += cplen;
150    }
151    HMAC_CTX_cleanup(&hctx_tpl);
152# ifdef DEBUG_PKCS5V2
153    fprintf(stderr, "Password:\n");
154    h__dump(pass, passlen);
155    fprintf(stderr, "Salt:\n");
156    h__dump(salt, saltlen);
157    fprintf(stderr, "Iteration count %d\n", iter);
158    fprintf(stderr, "Key:\n");
159    h__dump(out, keylen);
160# endif
161    return 1;
162}
163
164int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen,
165                           const unsigned char *salt, int saltlen, int iter,
166                           int keylen, unsigned char *out)
167{
168    return PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, EVP_sha1(),
169                             keylen, out);
170}
171
172# ifdef DO_TEST
173main()
174{
175    unsigned char out[4];
176    unsigned char salt[] = { 0x12, 0x34, 0x56, 0x78 };
177    PKCS5_PBKDF2_HMAC_SHA1("password", -1, salt, 4, 5, 4, out);
178    fprintf(stderr, "Out %02X %02X %02X %02X\n",
179            out[0], out[1], out[2], out[3]);
180}
181
182# endif
183
184/*
185 * Now the key derivation function itself. This is a bit evil because it has
186 * to check the ASN1 parameters are valid: and there are quite a few of
187 * them...
188 */
189
190int PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,
191                          ASN1_TYPE *param, const EVP_CIPHER *c,
192                          const EVP_MD *md, int en_de)
193{
194    const unsigned char *pbuf;
195    int plen;
196    PBE2PARAM *pbe2 = NULL;
197    const EVP_CIPHER *cipher;
198
199    int rv = 0;
200
201    if (param == NULL || param->type != V_ASN1_SEQUENCE ||
202        param->value.sequence == NULL) {
203        EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_DECODE_ERROR);
204        goto err;
205    }
206
207    pbuf = param->value.sequence->data;
208    plen = param->value.sequence->length;
209    if (!(pbe2 = d2i_PBE2PARAM(NULL, &pbuf, plen))) {
210        EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_DECODE_ERROR);
211        goto err;
212    }
213
214    /* See if we recognise the key derivation function */
215
216    if (OBJ_obj2nid(pbe2->keyfunc->algorithm) != NID_id_pbkdf2) {
217        EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
218               EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);
219        goto err;
220    }
221
222    /*
223     * lets see if we recognise the encryption algorithm.
224     */
225
226    cipher = EVP_get_cipherbyobj(pbe2->encryption->algorithm);
227
228    if (!cipher) {
229        EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_CIPHER);
230        goto err;
231    }
232
233    /* Fixup cipher based on AlgorithmIdentifier */
234    if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, en_de))
235        goto err;
236    if (EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) < 0) {
237        EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_CIPHER_PARAMETER_ERROR);
238        goto err;
239    }
240    rv = PKCS5_v2_PBKDF2_keyivgen(ctx, pass, passlen,
241                                  pbe2->keyfunc->parameter, c, md, en_de);
242 err:
243    PBE2PARAM_free(pbe2);
244    return rv;
245}
246
247int PKCS5_v2_PBKDF2_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass,
248                             int passlen, ASN1_TYPE *param,
249                             const EVP_CIPHER *c, const EVP_MD *md, int en_de)
250{
251    unsigned char *salt, key[EVP_MAX_KEY_LENGTH];
252    const unsigned char *pbuf;
253    int saltlen, iter, plen;
254    int rv = 0;
255    unsigned int keylen = 0;
256    int prf_nid, hmac_md_nid;
257    PBKDF2PARAM *kdf = NULL;
258    const EVP_MD *prfmd;
259
260    if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
261        EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_NO_CIPHER_SET);
262        goto err;
263    }
264    keylen = EVP_CIPHER_CTX_key_length(ctx);
265    OPENSSL_assert(keylen <= sizeof(key));
266
267    /* Decode parameter */
268
269    if (!param || (param->type != V_ASN1_SEQUENCE)) {
270        EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_DECODE_ERROR);
271        goto err;
272    }
273
274    pbuf = param->value.sequence->data;
275    plen = param->value.sequence->length;
276
277    if (!(kdf = d2i_PBKDF2PARAM(NULL, &pbuf, plen))) {
278        EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_DECODE_ERROR);
279        goto err;
280    }
281
282    keylen = EVP_CIPHER_CTX_key_length(ctx);
283
284    /* Now check the parameters of the kdf */
285
286    if (kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != (int)keylen)) {
287        EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_KEYLENGTH);
288        goto err;
289    }
290
291    if (kdf->prf)
292        prf_nid = OBJ_obj2nid(kdf->prf->algorithm);
293    else
294        prf_nid = NID_hmacWithSHA1;
295
296    if (!EVP_PBE_find(EVP_PBE_TYPE_PRF, prf_nid, NULL, &hmac_md_nid, 0)) {
297        EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
298        goto err;
299    }
300
301    prfmd = EVP_get_digestbynid(hmac_md_nid);
302    if (prfmd == NULL) {
303        EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
304        goto err;
305    }
306
307    if (kdf->salt->type != V_ASN1_OCTET_STRING) {
308        EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_SALT_TYPE);
309        goto err;
310    }
311
312    /* it seems that its all OK */
313    salt = kdf->salt->value.octet_string->data;
314    saltlen = kdf->salt->value.octet_string->length;
315    iter = ASN1_INTEGER_get(kdf->iter);
316    if (!PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, prfmd,
317                           keylen, key))
318        goto err;
319    rv = EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);
320 err:
321    OPENSSL_cleanse(key, keylen);
322    PBKDF2PARAM_free(kdf);
323    return rv;
324}
325
326# ifdef DEBUG_PKCS5V2
327static void h__dump(const unsigned char *p, int len)
328{
329    for (; len--; p++)
330        fprintf(stderr, "%02X ", *p);
331    fprintf(stderr, "\n");
332}
333# endif
334#endif
335