1 /*
2 * Copyright 2021 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 <openssl/core_names.h>
12 #include <openssl/crypto.h>
13 #include <openssl/kdf.h>
14 #include <openssl/obj_mac.h>
15 #include <openssl/params.h>
16
17 /*
18 * test vector from
19 * https://datatracker.ietf.org/doc/html/rfc5869
20 */
21
22 static unsigned char hkdf_salt[] = {
23 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
24 0x0c
25 };
26
27 static unsigned char hkdf_ikm[] = {
28 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
29 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b
30 };
31
32 static unsigned char hkdf_info[] = {
33 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9
34 };
35
36 /* Expected output keying material */
37 static unsigned char hkdf_okm[] = {
38 0x3c, 0xb2, 0x5f, 0x25, 0xfa, 0xac, 0xd5, 0x7a, 0x90, 0x43, 0x4f, 0x64,
39 0xd0, 0x36, 0x2f, 0x2a, 0x2d, 0x2d, 0x0a, 0x90, 0xcf, 0x1a, 0x5a, 0x4c,
40 0x5d, 0xb0, 0x2d, 0x56, 0xec, 0xc4, 0xc5, 0xbf, 0x34, 0x00, 0x72, 0x08,
41 0xd5, 0xb8, 0x87, 0x18, 0x58, 0x65
42 };
43
main(int argc,char ** argv)44 int main(int argc, char **argv)
45 {
46 int rv = 1;
47 EVP_KDF *kdf = NULL;
48 EVP_KDF_CTX *kctx = NULL;
49 unsigned char out[42];
50 OSSL_PARAM params[5], *p = params;
51 OSSL_LIB_CTX *library_context = NULL;
52
53 library_context = OSSL_LIB_CTX_new();
54 if (library_context == NULL) {
55 fprintf(stderr, "OSSL_LIB_CTX_new() returned NULL\n");
56 goto end;
57 }
58
59 /* Fetch the key derivation function implementation */
60 kdf = EVP_KDF_fetch(library_context, "HKDF", NULL);
61 if (kdf == NULL) {
62 fprintf(stderr, "EVP_KDF_fetch() returned NULL\n");
63 goto end;
64 }
65
66 /* Create a context for the key derivation operation */
67 kctx = EVP_KDF_CTX_new(kdf);
68 if (kctx == NULL) {
69 fprintf(stderr, "EVP_KDF_CTX_new() returned NULL\n");
70 goto end;
71 }
72
73 /* Set the underlying hash function used to derive the key */
74 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
75 "SHA256", 0);
76 /* Set input keying material */
77 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, hkdf_ikm,
78 sizeof(hkdf_ikm));
79 /* Set application specific information */
80 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_INFO, hkdf_info,
81 sizeof(hkdf_info));
82 /* Set salt */
83 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, hkdf_salt,
84 sizeof(hkdf_salt));
85 *p = OSSL_PARAM_construct_end();
86
87 /* Derive the key */
88 if (EVP_KDF_derive(kctx, out, sizeof(out), params) != 1) {
89 fprintf(stderr, "EVP_KDF_derive() failed\n");
90 goto end;
91 }
92
93 if (CRYPTO_memcmp(hkdf_okm, out, sizeof(hkdf_okm)) != 0) {
94 fprintf(stderr, "Generated key does not match expected value\n");
95 goto end;
96 }
97
98 rv = 0;
99 end:
100 EVP_KDF_CTX_free(kctx);
101 EVP_KDF_free(kdf);
102 OSSL_LIB_CTX_free(library_context);
103 return rv;
104 }
105