openssl/demos/kdf/hkdf.c
Marek a205860404 Add demo for HKDF
Fixes #14120

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15784)
2021-06-18 17:06:31 +10:00

105 lines
3.3 KiB
C

/*
* Copyright 2021 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/rfc5869
*/
static unsigned char hkdf_salt[] = {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
0x0c
};
static unsigned char hkdf_ikm[] = {
0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b
};
static unsigned char hkdf_info[] = {
0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9
};
/* Expected output keying material */
static unsigned char hkdf_okm[] = {
0x3c, 0xb2, 0x5f, 0x25, 0xfa, 0xac, 0xd5, 0x7a, 0x90, 0x43, 0x4f, 0x64,
0xd0, 0x36, 0x2f, 0x2a, 0x2d, 0x2d, 0x0a, 0x90, 0xcf, 0x1a, 0x5a, 0x4c,
0x5d, 0xb0, 0x2d, 0x56, 0xec, 0xc4, 0xc5, 0xbf, 0x34, 0x00, 0x72, 0x08,
0xd5, 0xb8, 0x87, 0x18, 0x58, 0x65
};
int main(int argc, char **argv)
{
int rv = 1;
EVP_KDF *kdf = NULL;
EVP_KDF_CTX *kctx = NULL;
unsigned char out[42];
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, "HKDF", 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 the underlying hash function used to derive the key */
*p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
"SHA256", 0);
/* Set input keying material */
*p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, hkdf_ikm,
sizeof(hkdf_ikm));
/* Set application specific information */
*p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_INFO, hkdf_info,
sizeof(hkdf_info));
/* Set salt */
*p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, hkdf_salt,
sizeof(hkdf_salt));
*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(hkdf_okm, out, sizeof(hkdf_okm)) != 0) {
fprintf(stderr, "Generated key does not match expected value\n");
goto end;
}
rv = 0;
end:
EVP_KDF_CTX_free(kctx);
EVP_KDF_free(kdf);
OSSL_LIB_CTX_free(library_context);
return rv;
}