/*

 * Copyright (C) 2014 Nikos Mavrogiannopoulos

 *

 * Author: Nikos Mavrogiannopoulos

 *

 * This file is part of GnuTLS.

 *

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

 * under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3 of the License, or

 * (at your option) any later version.

 *

 * GnuTLS 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

 * General Public License for more details.

 *

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

 * along with GnuTLS; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <stdio.h>

#include <stdlib.h>

#include <stdint.h>

#include <string.h>

#include <errno.h>

#include <gnutls/gnutls.h>

#include <gnutls/dtls.h>

#include <signal.h>

#include <unistd.h>

#include "utils.h"

#ifdef _WIN32

void doit(void)

{

	exit(77);

}

#else

#include <netinet/in.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <sys/wait.h>

/* Tests whether packing multiple DTLS records in a single UDP packet

 * will be handled correctly, as well as an asymmetry in MTU sizes

 * between server and client.

 */

const char *side = "";

static void tls_log_func(int level, const char *str)

{

	fprintf(stderr, "%s|<%d>| %s", side, level, str);

}

static ssize_t push(gnutls_transport_ptr_t tr, const void *data, size_t len)

{

	static uint8_t buffer[6 * 1024];

	static unsigned buffer_size = 0;

	const uint8_t *d = data;

	int fd = (long int)tr;

	int ret;

	if (buffer_size + len > sizeof(buffer)) {

		abort();

	}

	memcpy(&buffer[buffer_size], data, len);

	buffer_size += len;

	if (d[0] == 22) {	/* handshake */

		if (d[13] == GNUTLS_HANDSHAKE_CERTIFICATE_PKT ||

		    d[13] == GNUTLS_HANDSHAKE_CERTIFICATE_STATUS ||

		    d[13] == GNUTLS_HANDSHAKE_SERVER_KEY_EXCHANGE ||

		    d[13] == GNUTLS_HANDSHAKE_SERVER_HELLO ||

		    d[13] == GNUTLS_HANDSHAKE_CERTIFICATE_REQUEST ||

		    d[13] == GNUTLS_HANDSHAKE_NEW_SESSION_TICKET ||

		    d[13] == GNUTLS_HANDSHAKE_CERTIFICATE_VERIFY ||

		    d[13] == GNUTLS_HANDSHAKE_CLIENT_KEY_EXCHANGE) {

			if (debug)

				fprintf(stderr, "caching: %s (buffer: %d)\n",

					gnutls_handshake_description_get_name(d[13]),

					buffer_size);

			return len;

		} else if (debug) {

			fprintf(stderr, "sending: %s\n",

				gnutls_handshake_description_get_name(d[13]));

		}

	}

	if (debug)

		fprintf(stderr, "sending %d bytes\n", (int)buffer_size);

	ret = send(fd, buffer, buffer_size, 0);

	if (ret >= 0) {

		if (debug)

			fprintf(stderr, "reset cache\n");

		buffer_size = 0;

	}

	return len;

}

static unsigned char server_cert_pem[] =

  "-----BEGIN CERTIFICATE-----\n"

  "MIICHzCCAaWgAwIBAgIBCTAKBggqhkjOPQQDAjA+MQswCQYDVQQGEwJOTDERMA8G\n"

  "A1UEChMIUG9sYXJTU0wxHDAaBgNVBAMTE1BvbGFyc3NsIFRlc3QgRUMgQ0EwHhcN\n"

  "MTMwOTI0MTU1MjA0WhcNMjMwOTIyMTU1MjA0WjA0MQswCQYDVQQGEwJOTDERMA8G\n"

  "A1UEChMIUG9sYXJTU0wxEjAQBgNVBAMTCWxvY2FsaG9zdDBZMBMGByqGSM49AgEG\n"

  "CCqGSM49AwEHA0IABDfMVtl2CR5acj7HWS3/IG7ufPkGkXTQrRS192giWWKSTuUA\n"

  "2CMR/+ov0jRdXRa9iojCa3cNVc2KKg76Aci07f+jgZ0wgZowCQYDVR0TBAIwADAd\n"

  "BgNVHQ4EFgQUUGGlj9QH2deCAQzlZX+MY0anE74wbgYDVR0jBGcwZYAUnW0gJEkB\n"

  "PyvLeLUZvH4kydv7NnyhQqRAMD4xCzAJBgNVBAYTAk5MMREwDwYDVQQKEwhQb2xh\n"

  "clNTTDEcMBoGA1UEAxMTUG9sYXJzc2wgVGVzdCBFQyBDQYIJAMFD4n5iQ8zoMAoG\n"

  "CCqGSM49BAMCA2gAMGUCMQCaLFzXptui5WQN8LlO3ddh1hMxx6tzgLvT03MTVK2S\n"

  "C12r0Lz3ri/moSEpNZWqPjkCMCE2f53GXcYLqyfyJR078c/xNSUU5+Xxl7VZ414V\n"

  "fGa5kHvHARBPc8YAIVIqDvHH1Q==\n"

  "-----END CERTIFICATE-----\n";

const gnutls_datum_t server_cert = { server_cert_pem,

	sizeof(server_cert_pem)

};

static unsigned char server_key_pem[] =

  "-----BEGIN EC PRIVATE KEY-----\n"

  "MHcCAQEEIPEqEyB2AnCoPL/9U/YDHvdqXYbIogTywwyp6/UfDw6noAoGCCqGSM49\n"

  "AwEHoUQDQgAEN8xW2XYJHlpyPsdZLf8gbu58+QaRdNCtFLX3aCJZYpJO5QDYIxH/\n"

  "6i/SNF1dFr2KiMJrdw1VzYoqDvoByLTt/w==\n"

  "-----END EC PRIVATE KEY-----\n";

const gnutls_datum_t server_key = { server_key_pem,

	sizeof(server_key_pem)

};

static void client(int fd, unsigned cache)

{

	int ret;

	gnutls_certificate_credentials_t x509_cred;

	gnutls_session_t session;

	/* Need to enable anonymous KX specifically. */

	fd_set rfds;

	struct timeval tv;

	global_init();

	if (debug) {

		side = "client";

		gnutls_global_set_log_function(tls_log_func);

		gnutls_global_set_log_level(4711);

	}

	gnutls_certificate_allocate_credentials(&x509_cred);

	/* Initialize TLS session

	 */

	gnutls_init(&session, GNUTLS_CLIENT | GNUTLS_DATAGRAM);

	gnutls_dtls_set_mtu(session, 1500);

	gnutls_dtls_set_timeouts(session, 6 * 1000, 60 * 1000);

	//gnutls_transport_set_push_function(session, push);

	/* Use default priorities */

	gnutls_priority_set_direct(session,

				   "NONE:+VERS-DTLS-ALL:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ECDHE-ECDSA:+CURVE-ALL",

				   NULL);

	/* put the anonymous credentials to the current session

	 */

	gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, x509_cred);

	gnutls_transport_set_int(session, fd);

	/* Perform the TLS handshake

	 */

	do {

		ret = gnutls_handshake(session);

		if (ret == GNUTLS_E_AGAIN && gnutls_record_get_direction(session) == 0) {

			int rv;

			FD_ZERO(&rfds);

			FD_SET(fd, &rfds);

			tv.tv_sec = 2;

			tv.tv_usec = 0;

			rv = select(fd+1, &rfds, NULL, NULL, &tv;;

			if (rv == -1)

				perror("select()");

			else if (!rv)

				fail("test %d: No data were received.\n", cache);

		}

	}

	while (ret < 0 && gnutls_error_is_fatal(ret) == 0);

	if (ret < 0) {

		fail("client: Handshake failed\n");

		gnutls_perror(ret);

		exit(1);

	} else {

		if (debug)

			success("client: Handshake was completed\n");

	}

	if (debug)

		success("client: TLS version is: %s\n",

			gnutls_protocol_get_name

			(gnutls_protocol_get_version(session)));

	gnutls_bye(session, GNUTLS_SHUT_WR);

	close(fd);

	gnutls_deinit(session);

	gnutls_certificate_free_credentials(x509_cred);

	gnutls_global_deinit();

}

/* These are global */

pid_t child;

static void terminate(void)

{

	int status;

	kill(child, SIGTERM);

	wait(&status);

	exit(1);

}

static void server(int fd, unsigned cache)

{

	int ret;

	gnutls_certificate_credentials_t x509_cred;

	gnutls_session_t session;

	/* this must be called once in the program

	 */

	global_init();

#if 0

	if (debug) {

		side = "server";

		gnutls_global_set_log_function(tls_log_func);

		gnutls_global_set_log_level(4711);

	}

#endif

	gnutls_certificate_allocate_credentials(&x509_cred);

	gnutls_certificate_set_x509_key_mem(x509_cred, &server_cert,

					    &server_key,

					    GNUTLS_X509_FMT_PEM);

	gnutls_init(&session, GNUTLS_SERVER | GNUTLS_DATAGRAM);

	gnutls_dtls_set_timeouts(session, 5 * 1000, 60 * 1000);

	gnutls_dtls_set_mtu(session, 400);

	if (cache != 0)

		gnutls_transport_set_push_function(session, push);

	/* avoid calling all the priority functions, since the defaults

	 * are adequate.

	 */

	gnutls_priority_set_direct(session,

				   "NONE:+VERS-DTLS1.2:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ECDHE-ECDSA:+CURVE-ALL",

				   NULL);

	gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, x509_cred);

	gnutls_transport_set_int(session, fd);

	do {

		ret = gnutls_handshake(session);

	} while (ret < 0 && gnutls_error_is_fatal(ret) == 0);

	if (ret < 0) {

		close(fd);

		gnutls_deinit(session);

		fail("server: Handshake has failed (%s)\n\n",

		     gnutls_strerror(ret));

		terminate();

	}

	if (debug)

		success("server: Handshake was completed\n");

	if (debug)

		success("server: TLS version is: %s\n",

			gnutls_protocol_get_name

			(gnutls_protocol_get_version(session)));

	/* do not wait for the peer to close the connection.

	 */

	gnutls_bye(session, GNUTLS_SHUT_WR);

	close(fd);

	gnutls_deinit(session);

	gnutls_certificate_free_credentials(x509_cred);

	gnutls_global_deinit();

	if (debug)

		success("server: finished\n");

}

static

void run(unsigned cache)

{

	int fd[2];

	int ret;

	ret = socketpair(AF_UNIX, SOCK_STREAM, 0, fd);

	if (ret < 0) {

		perror("socketpair");

		exit(1);

	}

	child = fork();

	if (child < 0) {

		perror("fork");

		fail("fork");

		exit(1);

	}

	if (child) {

		int status;

		/* parent */

		close(fd[1]);

		client(fd[0], cache);

		wait(&status);

		check_wait_status(status);

	} else {

		close(fd[0]);

		server(fd[1], cache);

		exit(0);

	}

}

void doit(void)

{

	signal(SIGPIPE, SIG_IGN);

	run(0);

	run(1);

}

#endif				/* _WIN32 */