1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
|
/*
* Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include <stdlib.h>
#include "internal/cryptlib.h"
# include <openssl/x509.h>
# include <openssl/evp.h>
# include <openssl/hmac.h>
# include "evp_local.h"
/* set this to print out info about the keygen algorithm */
/* #define OPENSSL_DEBUG_PKCS5V2 */
# ifdef OPENSSL_DEBUG_PKCS5V2
static void h__dump(const unsigned char *p, int len);
# endif
/*
* This is an implementation of PKCS#5 v2.0 password based encryption key
* derivation function PBKDF2. SHA1 version verified against test vectors
* posted by Peter Gutmann to the PKCS-TNG mailing list.
*/
int 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)
{
const char *empty = "";
unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
int cplen, j, k, tkeylen, mdlen;
unsigned long i = 1;
HMAC_CTX *hctx_tpl = NULL, *hctx = NULL;
mdlen = EVP_MD_size(digest);
if (mdlen < 0)
return 0;
hctx_tpl = HMAC_CTX_new();
if (hctx_tpl == NULL)
return 0;
p = out;
tkeylen = keylen;
if (pass == NULL) {
pass = empty;
passlen = 0;
} else if (passlen == -1) {
passlen = strlen(pass);
}
if (!HMAC_Init_ex(hctx_tpl, pass, passlen, digest, NULL)) {
HMAC_CTX_free(hctx_tpl);
return 0;
}
hctx = HMAC_CTX_new();
if (hctx == NULL) {
HMAC_CTX_free(hctx_tpl);
return 0;
}
while (tkeylen) {
if (tkeylen > mdlen)
cplen = mdlen;
else
cplen = tkeylen;
/*
* We are unlikely to ever use more than 256 blocks (5120 bits!) but
* just in case...
*/
itmp[0] = (unsigned char)((i >> 24) & 0xff);
itmp[1] = (unsigned char)((i >> 16) & 0xff);
itmp[2] = (unsigned char)((i >> 8) & 0xff);
itmp[3] = (unsigned char)(i & 0xff);
if (!HMAC_CTX_copy(hctx, hctx_tpl)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
if (!HMAC_Update(hctx, salt, saltlen)
|| !HMAC_Update(hctx, itmp, 4)
|| !HMAC_Final(hctx, digtmp, NULL)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
memcpy(p, digtmp, cplen);
for (j = 1; j < iter; j++) {
if (!HMAC_CTX_copy(hctx, hctx_tpl)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
if (!HMAC_Update(hctx, digtmp, mdlen)
|| !HMAC_Final(hctx, digtmp, NULL)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
for (k = 0; k < cplen; k++)
p[k] ^= digtmp[k];
}
tkeylen -= cplen;
i++;
p += cplen;
}
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
# ifdef OPENSSL_DEBUG_PKCS5V2
fprintf(stderr, "Password:\n");
h__dump(pass, passlen);
fprintf(stderr, "Salt:\n");
h__dump(salt, saltlen);
fprintf(stderr, "Iteration count %d\n", iter);
fprintf(stderr, "Key:\n");
h__dump(out, keylen);
# endif
return 1;
}
int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen,
const unsigned char *salt, int saltlen, int iter,
int keylen, unsigned char *out)
{
return PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, EVP_sha1(),
keylen, out);
}
/*
* Now the key derivation function itself. This is a bit evil because it has
* to check the ASN1 parameters are valid: and there are quite a few of
* them...
*/
int 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)
{
PBE2PARAM *pbe2 = NULL;
const EVP_CIPHER *cipher;
EVP_PBE_KEYGEN *kdf;
int rv = 0;
pbe2 = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(PBE2PARAM), param);
if (pbe2 == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_DECODE_ERROR);
goto err;
}
/* See if we recognise the key derivation function */
if (!EVP_PBE_find(EVP_PBE_TYPE_KDF, OBJ_obj2nid(pbe2->keyfunc->algorithm),
NULL, NULL, &kdf)) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);
goto err;
}
/*
* lets see if we recognise the encryption algorithm.
*/
cipher = EVP_get_cipherbyobj(pbe2->encryption->algorithm);
if (!cipher) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_CIPHER);
goto err;
}
/* Fixup cipher based on AlgorithmIdentifier */
if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, en_de))
goto err;
if (EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) < 0) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_CIPHER_PARAMETER_ERROR);
goto err;
}
rv = kdf(ctx, pass, passlen, pbe2->keyfunc->parameter, NULL, NULL, en_de);
err:
PBE2PARAM_free(pbe2);
return rv;
}
int PKCS5_v2_PBKDF2_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass,
int passlen, ASN1_TYPE *param,
const EVP_CIPHER *c, const EVP_MD *md, int en_de)
{
unsigned char *salt, key[EVP_MAX_KEY_LENGTH];
int saltlen, iter;
int rv = 0;
unsigned int keylen = 0;
int prf_nid, hmac_md_nid;
PBKDF2PARAM *kdf = NULL;
const EVP_MD *prfmd;
if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_NO_CIPHER_SET);
goto err;
}
keylen = EVP_CIPHER_CTX_key_length(ctx);
OPENSSL_assert(keylen <= sizeof(key));
/* Decode parameter */
kdf = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(PBKDF2PARAM), param);
if (kdf == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_DECODE_ERROR);
goto err;
}
keylen = EVP_CIPHER_CTX_key_length(ctx);
/* Now check the parameters of the kdf */
if (kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != (int)keylen)) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_KEYLENGTH);
goto err;
}
if (kdf->prf)
prf_nid = OBJ_obj2nid(kdf->prf->algorithm);
else
prf_nid = NID_hmacWithSHA1;
if (!EVP_PBE_find(EVP_PBE_TYPE_PRF, prf_nid, NULL, &hmac_md_nid, 0)) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
goto err;
}
prfmd = EVP_get_digestbynid(hmac_md_nid);
if (prfmd == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
goto err;
}
if (kdf->salt->type != V_ASN1_OCTET_STRING) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_SALT_TYPE);
goto err;
}
/* it seems that its all OK */
salt = kdf->salt->value.octet_string->data;
saltlen = kdf->salt->value.octet_string->length;
iter = ASN1_INTEGER_get(kdf->iter);
if (!PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, prfmd,
keylen, key))
goto err;
rv = EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);
err:
OPENSSL_cleanse(key, keylen);
PBKDF2PARAM_free(kdf);
return rv;
}
# ifdef OPENSSL_DEBUG_PKCS5V2
static void h__dump(const unsigned char *p, int len)
{
for (; len--; p++)
fprintf(stderr, "%02X ", *p);
fprintf(stderr, "\n");
}
# endif
|
