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
|
/*
* Copyright 2021-2023 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (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 <openssl/core_names.h>
#include <openssl/crypto.h>
#include <openssl/kdf.h>
#include <openssl/obj_mac.h>
#include <openssl/params.h>
/*
* test vector from
* https://datatracker.ietf.org/doc/html/rfc7914
*/
/*
* Hard coding a password into an application is very bad.
* It is done here solely for educational purposes.
*/
static unsigned char password[] = {
'P', 'a', 's', 's', 'w', 'o', 'r', 'd'
};
/*
* The salt is better not being hard coded too. Each password should have a
* different salt if possible. The salt is not considered secret information
* and is safe to store with an encrypted password.
*/
static unsigned char pbkdf2_salt[] = {
'N', 'a', 'C', 'l'
};
/*
* The iteration parameter can be variable or hard coded. The disadvantage with
* hard coding them is that they cannot easily be adjusted for future
* technological improvements appear.
*/
static unsigned int pbkdf2_iterations = 80000;
static const unsigned char expected_output[] = {
0x4d, 0xdc, 0xd8, 0xf6, 0x0b, 0x98, 0xbe, 0x21,
0x83, 0x0c, 0xee, 0x5e, 0xf2, 0x27, 0x01, 0xf9,
0x64, 0x1a, 0x44, 0x18, 0xd0, 0x4c, 0x04, 0x14,
0xae, 0xff, 0x08, 0x87, 0x6b, 0x34, 0xab, 0x56,
0xa1, 0xd4, 0x25, 0xa1, 0x22, 0x58, 0x33, 0x54,
0x9a, 0xdb, 0x84, 0x1b, 0x51, 0xc9, 0xb3, 0x17,
0x6a, 0x27, 0x2b, 0xde, 0xbb, 0xa1, 0xd0, 0x78,
0x47, 0x8f, 0x62, 0xb3, 0x97, 0xf3, 0x3c, 0x8d
};
int main(int argc, char **argv)
{
int ret = EXIT_FAILURE;
EVP_KDF *kdf = NULL;
EVP_KDF_CTX *kctx = NULL;
unsigned char out[64];
OSSL_PARAM params[5], *p = params;
OSSL_LIB_CTX *library_context = NULL;
library_context = OSSL_LIB_CTX_new();
if (library_context == NULL) {
fprintf(stderr, "OSSL_LIB_CTX_new() returned NULL\n");
goto end;
}
/* Fetch the key derivation function implementation */
kdf = EVP_KDF_fetch(library_context, "PBKDF2", NULL);
if (kdf == NULL) {
fprintf(stderr, "EVP_KDF_fetch() returned NULL\n");
goto end;
}
/* Create a context for the key derivation operation */
kctx = EVP_KDF_CTX_new(kdf);
if (kctx == NULL) {
fprintf(stderr, "EVP_KDF_CTX_new() returned NULL\n");
goto end;
}
/* Set password */
*p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PASSWORD, password,
sizeof(password));
/* Set salt */
*p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, pbkdf2_salt,
sizeof(pbkdf2_salt));
/* Set iteration count (default 2048) */
*p++ = OSSL_PARAM_construct_uint(OSSL_KDF_PARAM_ITER, &pbkdf2_iterations);
/* Set the underlying hash function used to derive the key */
*p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
"SHA256", 0);
*p = OSSL_PARAM_construct_end();
/* Derive the key */
if (EVP_KDF_derive(kctx, out, sizeof(out), params) != 1) {
fprintf(stderr, "EVP_KDF_derive() failed\n");
goto end;
}
if (CRYPTO_memcmp(expected_output, out, sizeof(expected_output)) != 0) {
fprintf(stderr, "Generated key does not match expected value\n");
goto end;
}
ret = EXIT_SUCCESS;
end:
EVP_KDF_CTX_free(kctx);
EVP_KDF_free(kdf);
OSSL_LIB_CTX_free(library_context);
return ret;
}
|
