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
266
|
/*
* Copyright 2017-2018 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 <stdlib.h>
#include <string.h>
#include <openssl/hmac.h>
#include <openssl/kdf.h>
#include <openssl/evp.h>
#include "internal/cryptlib.h"
#include "crypto/evp.h"
#ifndef OPENSSL_NO_SCRYPT
static int atou64(const char *nptr, uint64_t *result);
typedef struct {
unsigned char *pass;
size_t pass_len;
unsigned char *salt;
size_t salt_len;
uint64_t N, r, p;
uint64_t maxmem_bytes;
} SCRYPT_PKEY_CTX;
/* Custom uint64_t parser since we do not have strtoull */
static int atou64(const char *nptr, uint64_t *result)
{
uint64_t value = 0;
while (*nptr) {
unsigned int digit;
uint64_t new_value;
if ((*nptr < '0') || (*nptr > '9')) {
return 0;
}
digit = (unsigned int)(*nptr - '0');
new_value = (value * 10) + digit;
if ((new_value < digit) || ((new_value - digit) / 10 != value)) {
/* Overflow */
return 0;
}
value = new_value;
nptr++;
}
*result = value;
return 1;
}
static int pkey_scrypt_init(EVP_PKEY_CTX *ctx)
{
SCRYPT_PKEY_CTX *kctx;
kctx = OPENSSL_zalloc(sizeof(*kctx));
if (kctx == NULL) {
KDFerr(KDF_F_PKEY_SCRYPT_INIT, ERR_R_MALLOC_FAILURE);
return 0;
}
/* Default values are the most conservative recommendation given in the
* original paper of C. Percival. Derivation uses roughly 1 GiB of memory
* for this parameter choice (approx. 128 * r * (N + p) bytes).
*/
kctx->N = 1 << 20;
kctx->r = 8;
kctx->p = 1;
kctx->maxmem_bytes = 1025 * 1024 * 1024;
ctx->data = kctx;
return 1;
}
static void pkey_scrypt_cleanup(EVP_PKEY_CTX *ctx)
{
SCRYPT_PKEY_CTX *kctx = ctx->data;
OPENSSL_clear_free(kctx->salt, kctx->salt_len);
OPENSSL_clear_free(kctx->pass, kctx->pass_len);
OPENSSL_free(kctx);
}
static int pkey_scrypt_set_membuf(unsigned char **buffer, size_t *buflen,
const unsigned char *new_buffer,
const int new_buflen)
{
if (new_buffer == NULL)
return 1;
if (new_buflen < 0)
return 0;
if (*buffer != NULL)
OPENSSL_clear_free(*buffer, *buflen);
if (new_buflen > 0) {
*buffer = OPENSSL_memdup(new_buffer, new_buflen);
} else {
*buffer = OPENSSL_malloc(1);
}
if (*buffer == NULL) {
KDFerr(KDF_F_PKEY_SCRYPT_SET_MEMBUF, ERR_R_MALLOC_FAILURE);
return 0;
}
*buflen = new_buflen;
return 1;
}
static int is_power_of_two(uint64_t value)
{
return (value != 0) && ((value & (value - 1)) == 0);
}
static int pkey_scrypt_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
{
SCRYPT_PKEY_CTX *kctx = ctx->data;
uint64_t u64_value;
switch (type) {
case EVP_PKEY_CTRL_PASS:
return pkey_scrypt_set_membuf(&kctx->pass, &kctx->pass_len, p2, p1);
case EVP_PKEY_CTRL_SCRYPT_SALT:
return pkey_scrypt_set_membuf(&kctx->salt, &kctx->salt_len, p2, p1);
case EVP_PKEY_CTRL_SCRYPT_N:
u64_value = *((uint64_t *)p2);
if ((u64_value <= 1) || !is_power_of_two(u64_value))
return 0;
kctx->N = u64_value;
return 1;
case EVP_PKEY_CTRL_SCRYPT_R:
u64_value = *((uint64_t *)p2);
if (u64_value < 1)
return 0;
kctx->r = u64_value;
return 1;
case EVP_PKEY_CTRL_SCRYPT_P:
u64_value = *((uint64_t *)p2);
if (u64_value < 1)
return 0;
kctx->p = u64_value;
return 1;
case EVP_PKEY_CTRL_SCRYPT_MAXMEM_BYTES:
u64_value = *((uint64_t *)p2);
if (u64_value < 1)
return 0;
kctx->maxmem_bytes = u64_value;
return 1;
default:
return -2;
}
}
static int pkey_scrypt_ctrl_uint64(EVP_PKEY_CTX *ctx, int type,
const char *value)
{
uint64_t int_value;
if (!atou64(value, &int_value)) {
KDFerr(KDF_F_PKEY_SCRYPT_CTRL_UINT64, KDF_R_VALUE_ERROR);
return 0;
}
return pkey_scrypt_ctrl(ctx, type, 0, &int_value);
}
static int pkey_scrypt_ctrl_str(EVP_PKEY_CTX *ctx, const char *type,
const char *value)
{
if (value == NULL) {
KDFerr(KDF_F_PKEY_SCRYPT_CTRL_STR, KDF_R_VALUE_MISSING);
return 0;
}
if (strcmp(type, "pass") == 0)
return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_PASS, value);
if (strcmp(type, "hexpass") == 0)
return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_PASS, value);
if (strcmp(type, "salt") == 0)
return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_SCRYPT_SALT, value);
if (strcmp(type, "hexsalt") == 0)
return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_SCRYPT_SALT, value);
if (strcmp(type, "N") == 0)
return pkey_scrypt_ctrl_uint64(ctx, EVP_PKEY_CTRL_SCRYPT_N, value);
if (strcmp(type, "r") == 0)
return pkey_scrypt_ctrl_uint64(ctx, EVP_PKEY_CTRL_SCRYPT_R, value);
if (strcmp(type, "p") == 0)
return pkey_scrypt_ctrl_uint64(ctx, EVP_PKEY_CTRL_SCRYPT_P, value);
if (strcmp(type, "maxmem_bytes") == 0)
return pkey_scrypt_ctrl_uint64(ctx, EVP_PKEY_CTRL_SCRYPT_MAXMEM_BYTES,
value);
KDFerr(KDF_F_PKEY_SCRYPT_CTRL_STR, KDF_R_UNKNOWN_PARAMETER_TYPE);
return -2;
}
static int pkey_scrypt_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
size_t *keylen)
{
SCRYPT_PKEY_CTX *kctx = ctx->data;
if (kctx->pass == NULL) {
KDFerr(KDF_F_PKEY_SCRYPT_DERIVE, KDF_R_MISSING_PASS);
return 0;
}
if (kctx->salt == NULL) {
KDFerr(KDF_F_PKEY_SCRYPT_DERIVE, KDF_R_MISSING_SALT);
return 0;
}
return EVP_PBE_scrypt((char *)kctx->pass, kctx->pass_len, kctx->salt,
kctx->salt_len, kctx->N, kctx->r, kctx->p,
kctx->maxmem_bytes, key, *keylen);
}
const EVP_PKEY_METHOD scrypt_pkey_meth = {
EVP_PKEY_SCRYPT,
0,
pkey_scrypt_init,
0,
pkey_scrypt_cleanup,
0, 0,
0, 0,
0,
0,
0,
0,
0, 0,
0, 0, 0, 0,
0, 0,
0, 0,
0,
pkey_scrypt_derive,
pkey_scrypt_ctrl,
pkey_scrypt_ctrl_str
};
#endif
|
