/*

 * Copyright (C) 2020 Red Hat, Inc.

 *

 * Author: Daiki Ueno

 *

 * This file is part of GnuTLS.

 *

 * The GnuTLS is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public License

 * as published by the Free Software Foundation; either version 2.1 of

 * the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>

 *

 */

#include "config.h"

#include <gnutls/gnutls.h>

#include <gnutls/crypto.h>

#include <assert.h>

#include <stdint.h>

#include "utils.h"

#define MAX_BUF 1024

static void

test_hkdf(gnutls_mac_algorithm_t mac,

	  const char *ikm_hex,

	  const char *salt_hex,

	  const char *info_hex,

	  size_t length,

	  const char *prk_hex,

	  const char *okm_hex)

{

	gnutls_datum_t hex;

	gnutls_datum_t ikm;

	gnutls_datum_t salt;

	gnutls_datum_t info;

	gnutls_datum_t prk;

	gnutls_datum_t okm;

	uint8_t buf[MAX_BUF];

	success("HKDF test with %s\n", gnutls_mac_get_name(mac));

	/* Test HKDF-Extract */

	hex.data = (void *)ikm_hex;

	hex.size = strlen(ikm_hex);

	assert(gnutls_hex_decode2(&hex, &ikm) >= 0);

	hex.data = (void *)salt_hex;

	hex.size = strlen(salt_hex);

	assert(gnutls_hex_decode2(&hex, &salt) >= 0);

	assert(gnutls_hkdf_extract(mac, &ikm, &salt, buf) >= 0);

	gnutls_free(ikm.data);

	gnutls_free(salt.data);

	prk.data = buf;

	prk.size = strlen(prk_hex) / 2;

	assert(gnutls_hex_encode2(&prk, &hex) >= 0);

	if (strcmp((char *)hex.data, prk_hex))

		fail("prk doesn't match: %s != %s\n",

		     (char *)hex.data, prk_hex);

	gnutls_free(hex.data);

	/* Test HKDF-Expand */

	hex.data = (void *)info_hex;

	hex.size = strlen(info_hex);

	assert(gnutls_hex_decode2(&hex, &info) >= 0);

	assert(gnutls_hkdf_expand(mac, &prk, &info, buf, length) >= 0);

	gnutls_free(info.data);

	okm.data = buf;

	okm.size = strlen(okm_hex) / 2;

	assert(gnutls_hex_encode2(&okm, &hex) >= 0);

	if (strcmp((char *)hex.data, okm_hex))

		fail("okm doesn't match: %s != %s\n",

		     (char *)hex.data, okm_hex);

	gnutls_free(hex.data);

}

static void

test_pbkdf2(gnutls_mac_algorithm_t mac,

	    const char *ikm_hex,

	    const char *salt_hex,

	    unsigned iter_count,

	    size_t length,

	    const char *okm_hex)

{

	gnutls_datum_t hex;

	gnutls_datum_t ikm;

	gnutls_datum_t salt;

	gnutls_datum_t okm;

	uint8_t buf[MAX_BUF];

	success("PBKDF2 test with %s\n", gnutls_mac_get_name(mac));

	hex.data = (void *)ikm_hex;

	hex.size = strlen(ikm_hex);

	assert(gnutls_hex_decode2(&hex, &ikm) >= 0);

	hex.data = (void *)salt_hex;

	hex.size = strlen(salt_hex);

	assert(gnutls_hex_decode2(&hex, &salt) >= 0);

	assert(gnutls_pbkdf2(mac, &ikm, &salt, iter_count, buf, length) >= 0);

	gnutls_free(ikm.data);

	gnutls_free(salt.data);

	okm.data = buf;

	okm.size = length;

	assert(gnutls_hex_encode2(&okm, &hex) >= 0);

	if (strcmp((char *)hex.data, okm_hex))

		fail("okm doesn't match: %s != %s\n",

		     (char *)hex.data, okm_hex);

	gnutls_free(hex.data);

}

void

doit(void)

{

	/* Test vector from RFC 5869.  More thorough testing is done

	 * in nettle. */

	test_hkdf(GNUTLS_MAC_SHA256,

		  "0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b"

		  "0b0b0b0b0b0b",

		  "000102030405060708090a0b0c",

		  "f0f1f2f3f4f5f6f7f8f9",

		  42,

		  "077709362c2e32df0ddc3f0dc47bba63"

		  "90b6c73bb50f9c3122ec844ad7c2b3e5",

		  "3cb25f25faacd57a90434f64d0362f2a"

		  "2d2d0a90cf1a5a4c5db02d56ecc4c5bf"

		  "34007208d5b887185865");

	/* Test vector from RFC 6070.  More thorough testing is done

	 * in nettle. */

	test_pbkdf2(GNUTLS_MAC_SHA1,

		    "70617373776f7264", /* "password" */

		    "73616c74",		/* "salt" */

		    4096,

		    20,

		    "4b007901b765489abead49d926f721d065a429c1");

}