/*

 * Copyright (C) 2013-2015 Nikos Mavrogiannopoulos

 * Copyright (C) 2015 Red Hat, Inc.

 *

 * 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>

/* This checks the proper behavior of the client when

 * invalid data are sent by the server in the hello verify

 * request.

 */

#if defined(_WIN32)

int main()

{

	exit(77);

}

#else

#include <string.h>

#include <sys/types.h>

#include <netinet/in.h>

#include <sys/socket.h>

#include <sys/wait.h>

#include <arpa/inet.h>

#include <unistd.h>

#include <sys/select.h>

#include <errno.h>

#include <signal.h>

#include <gnutls/gnutls.h>

#include <gnutls/dtls.h>

#include "utils.h"

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

{

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

}

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

{

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

}

#define MAX_BUF 1024

static ssize_t

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

{

	int fd = (long int) tr;

	return send(fd, data, len, 0);

}

static void client(int fd)

{

	int ret;

	gnutls_anon_client_credentials_t anoncred;

	gnutls_session_t session;

	/* Need to enable anonymous KX specifically. */

	global_init();

	if (debug) {

		gnutls_global_set_log_function(client_log_func);

		gnutls_global_set_log_level(4711);

	}

	gnutls_anon_allocate_client_credentials(&anoncred);

	/* Initialize TLS session

	 */

	gnutls_init(&session, GNUTLS_CLIENT | GNUTLS_DATAGRAM);

	gnutls_dtls_set_mtu(session, 1500);

	gnutls_handshake_set_timeout(session, 20 * 1000);

	/* Use default priorities */

	gnutls_priority_set_direct(session,

				   "NONE:+VERS-DTLS-ALL:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ANON-ECDH:+CURVE-ALL",

				   NULL);

	/* put the anonymous credentials to the current session

	 */

	gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);

	gnutls_transport_set_int(session, fd);

	gnutls_transport_set_push_function(session, push);

	/* Perform the TLS handshake

	 */

	do {

		ret = gnutls_handshake(session);

	}

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

	if (ret < 0) {

		success("client: Handshake failed as expected\n");

		gnutls_perror(ret);

		goto exit;

	} else {

		fail("client: Handshake completed unexpectedly\n");

		goto exit;

	}

 exit:

	gnutls_deinit(session);

	gnutls_anon_free_client_credentials(anoncred);

	gnutls_global_deinit();

}

/* These are global */

pid_t child;

#define CLI_ADDR (void*)"test"

#define CLI_ADDR_LEN 4

static

ssize_t recv_timeout(int sockfd, void *buf, size_t len, unsigned flags, unsigned sec)

{

int ret;

struct timeval tv;

fd_set set;

	tv.tv_sec = sec;

	tv.tv_usec = 0;

	FD_ZERO(&set);

	FD_SET(sockfd, &set);

	do {

		ret = select(sockfd + 1, &set, NULL, NULL, &tv;;

	} while (ret == -1 && errno == EINTR);

	if (ret == -1 || ret == 0) {

		errno = ETIMEDOUT;

		return -1;

	}

	return recv(sockfd, buf, len, flags);

}

#define SERV_TIMEOUT 30

static void server(int fd)

{

	int ret, csend = 0;

	gnutls_anon_server_credentials_t anoncred;

	char buffer[MAX_BUF + 1];

	gnutls_datum_t cookie_key;

	gnutls_dtls_prestate_st prestate;

	gnutls_session_t session;

	unsigned try = 0;

	/* this must be called once in the program

	 */

	global_init();

	if (debug) {

		gnutls_global_set_log_function(server_log_func);

		gnutls_global_set_log_level(4711);

	}

	ret = gnutls_key_generate(&cookie_key, GNUTLS_COOKIE_KEY_SIZE);

	if (ret < 0) {

		fail("Cannot generate key: %s\n", gnutls_strerror(ret));

		exit(1);

	}

	gnutls_anon_allocate_server_credentials(&anoncred);

	gnutls_init(&session, GNUTLS_SERVER | GNUTLS_DATAGRAM);

	gnutls_handshake_set_timeout(session, SERV_TIMEOUT * 1000);

	gnutls_dtls_set_mtu(session, 1500);

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

	 * are adequate.

	 */

	gnutls_priority_set_direct(session,

				   "NONE:+VERS-DTLS1.0:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ANON-ECDH:+CURVE-ALL",

				   NULL);

	gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);

	gnutls_transport_set_int(session, fd);

	gnutls_transport_set_push_function(session, push);

	for (;;) {

		ret = recv_timeout(fd, buffer, sizeof(buffer), MSG_PEEK, SERV_TIMEOUT);

		if (ret < 0) {

			if (try != 0) {

				success("Server was terminated as expected!\n");

				goto exit;

			} else {

				fail("Error receiving first message\n");

				exit(1);

			}

		}

		try++;

		memset(&prestate, 0, sizeof(prestate));

		prestate.record_seq = 105791312;

		prestate.hsk_write_seq = 67166359;

		ret =

		    gnutls_dtls_cookie_verify(&cookie_key, CLI_ADDR,

					      CLI_ADDR_LEN, buffer, ret,

					      &prestate);

		if (ret < 0) {	/* cookie not valid */

			if (debug)

				success("Sending hello verify request\n");

			ret =

			    gnutls_dtls_cookie_send(&cookie_key, CLI_ADDR,

						    CLI_ADDR_LEN,

						    &prestate,

						    (gnutls_transport_ptr_t)

						    (long) fd, push);

			if (ret < 0) {

				fail("Cannot send data\n");

				exit(1);

			}

			/* discard peeked data */

			recv_timeout(fd, buffer, sizeof(buffer), 0, SERV_TIMEOUT);

			csend++;

			if (csend > 2) {

				fail("too many cookies sent\n");

				exit(1);

			}

			continue;

		}

		/* success */

		break;

	}

	fail("Shouldn't have reached here\n");

	exit(1);

 exit:

	gnutls_deinit(session);

	gnutls_free(cookie_key.data);

	gnutls_anon_free_server_credentials(anoncred);

	gnutls_global_deinit();

}

void doit(void)

{

	int fd[2];

	int ret;

	signal(SIGPIPE, SIG_IGN);

	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 */

		client(fd[0]);

		wait(&status);

		check_wait_status(status);

	} else {

		close(fd[0]);

		server(fd[1]);

		exit(0);

	}

}

#endif				/* _WIN32 */