1/*
2 * Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include <stdio.h>
11#include "internal/cryptlib.h"
12#include <openssl/asn1t.h>
13#include <openssl/err.h>
14#include <openssl/evp.h>
15#include <openssl/x509.h>
16#include <openssl/rand.h>
17
18#ifndef OPENSSL_NO_SCRYPT
19/* PKCS#5 scrypt password based encryption structures */
20
21ASN1_SEQUENCE(SCRYPT_PARAMS) = {
22 ASN1_SIMPLE(SCRYPT_PARAMS, salt, ASN1_OCTET_STRING),
23 ASN1_SIMPLE(SCRYPT_PARAMS, costParameter, ASN1_INTEGER),
24 ASN1_SIMPLE(SCRYPT_PARAMS, blockSize, ASN1_INTEGER),
25 ASN1_SIMPLE(SCRYPT_PARAMS, parallelizationParameter, ASN1_INTEGER),
26 ASN1_OPT(SCRYPT_PARAMS, keyLength, ASN1_INTEGER),
27} ASN1_SEQUENCE_END(SCRYPT_PARAMS)
28
29IMPLEMENT_ASN1_FUNCTIONS(SCRYPT_PARAMS)
30
31static X509_ALGOR *pkcs5_scrypt_set(const unsigned char *salt, size_t saltlen,
32 size_t keylen, uint64_t N, uint64_t r,
33 uint64_t p);
34
35/*
36 * Return an algorithm identifier for a PKCS#5 v2.0 PBE algorithm using scrypt
37 */
38
39X509_ALGOR *PKCS5_pbe2_set_scrypt(const EVP_CIPHER *cipher,
40 const unsigned char *salt, int saltlen,
41 unsigned char *aiv, uint64_t N, uint64_t r,
42 uint64_t p)
43{
44 X509_ALGOR *scheme = NULL, *ret = NULL;
45 int alg_nid;
46 size_t keylen = 0;
47 EVP_CIPHER_CTX *ctx = NULL;
48 unsigned char iv[EVP_MAX_IV_LENGTH];
49 PBE2PARAM *pbe2 = NULL;
50
51 if (!cipher) {
52 ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT, ERR_R_PASSED_NULL_PARAMETER);
53 goto err;
54 }
55
56 if (EVP_PBE_scrypt(NULL, 0, NULL, 0, N, r, p, 0, NULL, 0) == 0) {
57 ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT,
58 ASN1_R_INVALID_SCRYPT_PARAMETERS);
59 goto err;
60 }
61
62 alg_nid = EVP_CIPHER_type(cipher);
63 if (alg_nid == NID_undef) {
64 ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT,
65 ASN1_R_CIPHER_HAS_NO_OBJECT_IDENTIFIER);
66 goto err;
67 }
68
69 pbe2 = PBE2PARAM_new();
70 if (pbe2 == NULL)
71 goto merr;
72
73 /* Setup the AlgorithmIdentifier for the encryption scheme */
74 scheme = pbe2->encryption;
75
76 scheme->algorithm = OBJ_nid2obj(alg_nid);
77 scheme->parameter = ASN1_TYPE_new();
78 if (scheme->parameter == NULL)
79 goto merr;
80
81 /* Create random IV */
82 if (EVP_CIPHER_iv_length(cipher)) {
83 if (aiv)
84 memcpy(iv, aiv, EVP_CIPHER_iv_length(cipher));
85 else if (RAND_bytes(iv, EVP_CIPHER_iv_length(cipher)) <= 0)
86 goto err;
87 }
88
89 ctx = EVP_CIPHER_CTX_new();
90 if (ctx == NULL)
91 goto merr;
92
93 /* Dummy cipherinit to just setup the IV */
94 if (EVP_CipherInit_ex(ctx, cipher, NULL, NULL, iv, 0) == 0)
95 goto err;
96 if (EVP_CIPHER_param_to_asn1(ctx, scheme->parameter) <= 0) {
97 ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT,
98 ASN1_R_ERROR_SETTING_CIPHER_PARAMS);
99 goto err;
100 }
101 EVP_CIPHER_CTX_free(ctx);
102 ctx = NULL;
103
104 /* If its RC2 then we'd better setup the key length */
105
106 if (alg_nid == NID_rc2_cbc)
107 keylen = EVP_CIPHER_key_length(cipher);
108
109 /* Setup keyfunc */
110
111 X509_ALGOR_free(pbe2->keyfunc);
112
113 pbe2->keyfunc = pkcs5_scrypt_set(salt, saltlen, keylen, N, r, p);
114
115 if (pbe2->keyfunc == NULL)
116 goto merr;
117
118 /* Now set up top level AlgorithmIdentifier */
119
120 ret = X509_ALGOR_new();
121 if (ret == NULL)
122 goto merr;
123
124 ret->algorithm = OBJ_nid2obj(NID_pbes2);
125
126 /* Encode PBE2PARAM into parameter */
127
128 if (ASN1_TYPE_pack_sequence(ASN1_ITEM_rptr(PBE2PARAM), pbe2,
129 &ret->parameter) == NULL)
130 goto merr;
131
132 PBE2PARAM_free(pbe2);
133 pbe2 = NULL;
134
135 return ret;
136
137 merr:
138 ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT, ERR_R_MALLOC_FAILURE);
139
140 err:
141 PBE2PARAM_free(pbe2);
142 X509_ALGOR_free(ret);
143 EVP_CIPHER_CTX_free(ctx);
144
145 return NULL;
146}
147
148static X509_ALGOR *pkcs5_scrypt_set(const unsigned char *salt, size_t saltlen,
149 size_t keylen, uint64_t N, uint64_t r,
150 uint64_t p)
151{
152 X509_ALGOR *keyfunc = NULL;
153 SCRYPT_PARAMS *sparam = SCRYPT_PARAMS_new();
154
155 if (sparam == NULL)
156 goto merr;
157
158 if (!saltlen)
159 saltlen = PKCS5_SALT_LEN;
160
161 /* This will either copy salt or grow the buffer */
162 if (ASN1_STRING_set(sparam->salt, salt, saltlen) == 0)
163 goto merr;
164
165 if (salt == NULL && RAND_bytes(sparam->salt->data, saltlen) <= 0)
166 goto err;
167
168 if (ASN1_INTEGER_set_uint64(sparam->costParameter, N) == 0)
169 goto merr;
170
171 if (ASN1_INTEGER_set_uint64(sparam->blockSize, r) == 0)
172 goto merr;
173
174 if (ASN1_INTEGER_set_uint64(sparam->parallelizationParameter, p) == 0)
175 goto merr;
176
177 /* If have a key len set it up */
178
179 if (keylen > 0) {
180 sparam->keyLength = ASN1_INTEGER_new();
181 if (sparam->keyLength == NULL)
182 goto merr;
183 if (ASN1_INTEGER_set_int64(sparam->keyLength, keylen) == 0)
184 goto merr;
185 }
186
187 /* Finally setup the keyfunc structure */
188
189 keyfunc = X509_ALGOR_new();
190 if (keyfunc == NULL)
191 goto merr;
192
193 keyfunc->algorithm = OBJ_nid2obj(NID_id_scrypt);
194
195 /* Encode SCRYPT_PARAMS into parameter of pbe2 */
196
197 if (ASN1_TYPE_pack_sequence(ASN1_ITEM_rptr(SCRYPT_PARAMS), sparam,
198 &keyfunc->parameter) == NULL)
199 goto merr;
200
201 SCRYPT_PARAMS_free(sparam);
202 return keyfunc;
203
204 merr:
205 ASN1err(ASN1_F_PKCS5_SCRYPT_SET, ERR_R_MALLOC_FAILURE);
206 err:
207 SCRYPT_PARAMS_free(sparam);
208 X509_ALGOR_free(keyfunc);
209 return NULL;
210}
211
212int PKCS5_v2_scrypt_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass,
213 int passlen, ASN1_TYPE *param,
214 const EVP_CIPHER *c, const EVP_MD *md, int en_de)
215{
216 unsigned char *salt, key[EVP_MAX_KEY_LENGTH];
217 uint64_t p, r, N;
218 size_t saltlen;
219 size_t keylen = 0;
220 int t, rv = 0;
221 SCRYPT_PARAMS *sparam = NULL;
222
223 if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
224 EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN, EVP_R_NO_CIPHER_SET);
225 goto err;
226 }
227
228 /* Decode parameter */
229
230 sparam = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(SCRYPT_PARAMS), param);
231
232 if (sparam == NULL) {
233 EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN, EVP_R_DECODE_ERROR);
234 goto err;
235 }
236
237 t = EVP_CIPHER_CTX_key_length(ctx);
238 if (t < 0) {
239 EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN, EVP_R_INVALID_KEY_LENGTH);
240 goto err;
241 }
242 keylen = t;
243
244 /* Now check the parameters of sparam */
245
246 if (sparam->keyLength) {
247 uint64_t spkeylen;
248 if ((ASN1_INTEGER_get_uint64(&spkeylen, sparam->keyLength) == 0)
249 || (spkeylen != keylen)) {
250 EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN,
251 EVP_R_UNSUPPORTED_KEYLENGTH);
252 goto err;
253 }
254 }
255 /* Check all parameters fit in uint64_t and are acceptable to scrypt */
256 if (ASN1_INTEGER_get_uint64(&N, sparam->costParameter) == 0
257 || ASN1_INTEGER_get_uint64(&r, sparam->blockSize) == 0
258 || ASN1_INTEGER_get_uint64(&p, sparam->parallelizationParameter) == 0
259 || EVP_PBE_scrypt(NULL, 0, NULL, 0, N, r, p, 0, NULL, 0) == 0) {
260 EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN,
261 EVP_R_ILLEGAL_SCRYPT_PARAMETERS);
262 goto err;
263 }
264
265 /* it seems that its all OK */
266
267 salt = sparam->salt->data;
268 saltlen = sparam->salt->length;
269 if (EVP_PBE_scrypt(pass, passlen, salt, saltlen, N, r, p, 0, key, keylen)
270 == 0)
271 goto err;
272 rv = EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);
273 err:
274 if (keylen)
275 OPENSSL_cleanse(key, keylen);
276 SCRYPT_PARAMS_free(sparam);
277 return rv;
278}
279#endif /* OPENSSL_NO_SCRYPT */
280