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/*
* Copyright (C) 2012 Free Software Foundation, 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>
#if defined(_WIN32) || !defined(ENABLE_DTLS_SRTP)
int main(int argc, char **argv)
{
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 <signal.h>
#include <gnutls/gnutls.h>
#include <gnutls/dtls.h>
#include "utils.h"
static void terminate(void);
/* This program tests the rehandshake in DTLS
*/
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);
}
/* These are global */
static pid_t child;
#define MAX_KEY_MATERIAL 64*4
/* A very basic DTLS client, with anonymous authentication, that negotiates SRTP
*/
static void client(int fd, int profile)
{
gnutls_session_t session;
int ret;
gnutls_anon_client_credentials_t anoncred;
uint8_t km[MAX_KEY_MATERIAL];
char buf[2 * MAX_KEY_MATERIAL];
gnutls_datum_t cli_key, cli_salt, server_key, server_salt;
/* 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_heartbeat_enable(session, GNUTLS_HB_PEER_ALLOWED_TO_SEND);
gnutls_dtls_set_mtu(session, 1500);
/* Use default priorities */
gnutls_priority_set_direct(session,
"NONE:+VERS-DTLS1.0:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ANON-ECDH:+CURVE-ALL",
NULL);
if (profile)
ret =
gnutls_srtp_set_profile_direct(session,
"SRTP_AES128_CM_HMAC_SHA1_80",
NULL);
else
ret =
gnutls_srtp_set_profile_direct(session,
"SRTP_NULL_HMAC_SHA1_80",
NULL);
if (ret < 0) {
gnutls_perror(ret);
exit(1);
}
/* put the anonymous credentials to the current session
*/
gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);
gnutls_transport_set_int(session, fd);
/* Perform the TLS handshake
*/
do {
ret = gnutls_handshake(session);
}
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: DTLS version is: %s\n",
gnutls_protocol_get_name
(gnutls_protocol_get_version(session)));
ret =
gnutls_srtp_get_keys(session, km, sizeof(km), &cli_key,
&cli_salt, &server_key, &server_salt);
if (ret < 0) {
gnutls_perror(ret);
exit(1);
}
if (debug) {
size_t size = sizeof(buf);
gnutls_hex_encode(&cli_key, buf, &size);
success("Client key: %s\n", buf);
size = sizeof(buf);
gnutls_hex_encode(&cli_salt, buf, &size);
success("Client salt: %s\n", buf);
size = sizeof(buf);
gnutls_hex_encode(&server_key, buf, &size);
success("Server key: %s\n", buf);
size = sizeof(buf);
gnutls_hex_encode(&server_salt, buf, &size);
success("Server salt: %s\n", buf);
}
gnutls_bye(session, GNUTLS_SHUT_WR);
close(fd);
gnutls_deinit(session);
gnutls_anon_free_client_credentials(anoncred);
gnutls_global_deinit();
}
static void terminate(void)
{
int status;
assert(child);
kill(child, SIGTERM);
wait(&status);
exit(1);
}
static void server(int fd, int profile)
{
int ret;
gnutls_session_t session;
gnutls_anon_server_credentials_t anoncred;
uint8_t km[MAX_KEY_MATERIAL];
char buf[2 * MAX_KEY_MATERIAL];
gnutls_datum_t cli_key, cli_salt, server_key, server_salt;
/* 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);
}
gnutls_anon_allocate_server_credentials(&anoncred);
gnutls_init(&session, GNUTLS_SERVER | GNUTLS_DATAGRAM);
gnutls_heartbeat_enable(session, GNUTLS_HB_PEER_ALLOWED_TO_SEND);
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);
if (profile)
ret =
gnutls_srtp_set_profile_direct(session,
"SRTP_AES128_CM_HMAC_SHA1_80",
NULL);
else
ret =
gnutls_srtp_set_profile_direct(session,
"SRTP_NULL_HMAC_SHA1_80",
NULL);
if (ret < 0) {
gnutls_perror(ret);
exit(1);
}
gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);
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)));
ret =
gnutls_srtp_get_keys(session, km, sizeof(km), &cli_key,
&cli_salt, &server_key, &server_salt);
if (ret < 0) {
gnutls_perror(ret);
exit(1);
}
if (debug) {
size_t size = sizeof(buf);
gnutls_hex_encode(&cli_key, buf, &size);
success("Client key: %s\n", buf);
size = sizeof(buf);
gnutls_hex_encode(&cli_salt, buf, &size);
success("Client salt: %s\n", buf);
size = sizeof(buf);
gnutls_hex_encode(&server_key, buf, &size);
success("Server key: %s\n", buf);
size = sizeof(buf);
gnutls_hex_encode(&server_salt, buf, &size);
success("Server salt: %s\n", buf);
}
/* do not wait for the peer to close the connection.
*/
gnutls_bye(session, GNUTLS_SHUT_WR);
close(fd);
gnutls_deinit(session);
gnutls_anon_free_server_credentials(anoncred);
gnutls_global_deinit();
if (debug)
success("server: finished\n");
}
static void start(int profile)
{
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 */
server(fd[0], profile);
wait(&status);
check_wait_status(status);
} else {
close(fd[0]);
client(fd[1], profile);
exit(0);
}
}
void doit(void)
{
start(0);
start(1);
}
#endif /* _WIN32 */
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