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/*
* Copyright (C) 2004, 2005, 2008, 2009, 2010 Free Software Foundation,
* Inc.
*
* Author: Simon Josefsson
*
* 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
*/
/* Parts copied from GnuTLS example programs. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <gnutls/gnutls.h>
#include "tcp.c"
#include "utils.h"
/* A very basic TLS client, with PSK authentication.
*/
#define MAX_BUF 1024
#define MSG "Hello TLS"
static void
tls_log_func (int level, const char *str)
{
fprintf (stderr, "|<%d>| %s", level, str);
}
static void
client (void)
{
int ret, sd, ii;
gnutls_session_t session;
char buffer[MAX_BUF + 1];
gnutls_psk_client_credentials_t pskcred;
const gnutls_datum_t key = { (char *) "DEADBEEF", 8 };
gnutls_global_init ();
gnutls_global_set_log_function (tls_log_func);
// gnutls_global_set_log_level (99);
gnutls_psk_allocate_client_credentials (&pskcred);
gnutls_psk_set_client_credentials (pskcred, "test", &key,
GNUTLS_PSK_KEY_HEX);
/* Initialize TLS session
*/
gnutls_init (&session, GNUTLS_CLIENT);
/* Use default priorities */
gnutls_set_default_priority (session);
/* put the anonymous credentials to the current session
*/
gnutls_credentials_set (session, GNUTLS_CRD_PSK, pskcred);
/* connect to the peer
*/
sd = tcp_connect ();
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
/* Perform the TLS handshake
*/
ret = gnutls_handshake (session);
if (ret < 0)
{
fail ("client: Handshake failed\n");
gnutls_perror (ret);
goto end;
}
else
{
success ("client: Handshake was completed\n");
}
gnutls_record_send (session, MSG, strlen (MSG));
ret = gnutls_record_recv (session, buffer, MAX_BUF);
if (ret == 0)
{
success ("client: Peer has closed the TLS connection\n");
goto end;
}
else if (ret < 0)
{
fail ("client: Error: %s\n", gnutls_strerror (ret));
goto end;
}
printf ("- Received %d bytes: ", ret);
for (ii = 0; ii < ret; ii++)
fputc (buffer[ii], stdout);
fputs ("\n", stdout);
gnutls_bye (session, GNUTLS_SHUT_RDWR);
end:
tcp_close (sd);
gnutls_deinit (session);
gnutls_psk_free_client_credentials (pskcred);
gnutls_global_deinit ();
}
/* This is a sample TLS 1.0 echo server, for PSK authentication.
*/
#define SA struct sockaddr
#define MAX_BUF 1024
#define PORT 5556 /* listen to 5556 port */
/* These are global */
gnutls_psk_server_credentials_t server_pskcred;
static gnutls_session_t
initialize_tls_session (void)
{
gnutls_session_t session;
gnutls_init (&session, GNUTLS_SERVER);
/* avoid calling all the priority functions, since the defaults
* are adequate.
*/
gnutls_set_default_priority (session);
gnutls_credentials_set (session, GNUTLS_CRD_PSK, server_pskcred);
return session;
}
static gnutls_dh_params_t dh_params;
static int
generate_dh_params (void)
{
const gnutls_datum_t p3 = { (char *) pkcs3, strlen (pkcs3) };
/* Generate Diffie-Hellman parameters - for use with DHE
* kx algorithms. These should be discarded and regenerated
* once a day, once a week or once a month. Depending on the
* security requirements.
*/
gnutls_dh_params_init (&dh_params);
return gnutls_dh_params_import_pkcs3 (dh_params, &p3, GNUTLS_X509_FMT_PEM);
}
static int
pskfunc (gnutls_session_t session, const char *username, gnutls_datum_t * key)
{
printf ("psk callback to get %s's password\n", username);
key->data = gnutls_malloc (4);
key->data[0] = 0xDE;
key->data[1] = 0xAD;
key->data[2] = 0xBE;
key->data[3] = 0xEF;
key->size = 4;
return 0;
}
int err, listen_sd, i;
int sd, ret;
struct sockaddr_in sa_serv;
struct sockaddr_in sa_cli;
int client_len;
char topbuf[512];
gnutls_session_t session;
char buffer[MAX_BUF + 1];
int optval = 1;
static void
server_start (void)
{
success ("Launched, generating DH parameters...\n");
/* Socket operations
*/
listen_sd = socket (AF_INET, SOCK_STREAM, 0);
if (err == -1)
{
perror ("socket");
fail ("server: socket failed\n");
return;
}
memset (&sa_serv, '\0', sizeof (sa_serv));
sa_serv.sin_family = AF_INET;
sa_serv.sin_addr.s_addr = INADDR_ANY;
sa_serv.sin_port = htons (PORT); /* Server Port number */
setsockopt (listen_sd, SOL_SOCKET, SO_REUSEADDR, (void *) &optval,
sizeof (int));
err = bind (listen_sd, (SA *) & sa_serv, sizeof (sa_serv));
if (err == -1)
{
perror ("bind");
fail ("server: bind failed\n");
return;
}
err = listen (listen_sd, 1024);
if (err == -1)
{
perror ("listen");
fail ("server: listen failed\n");
return;
}
success ("server: ready. Listening to port '%d'.\n", PORT);
}
static void
server (void)
{
/* this must be called once in the program
*/
gnutls_global_init ();
gnutls_global_set_log_function (tls_log_func);
if (debug)
gnutls_global_set_log_level (4711);
generate_dh_params ();
gnutls_psk_allocate_server_credentials (&server_pskcred);
gnutls_psk_set_server_credentials_function (server_pskcred, pskfunc);
gnutls_psk_set_server_dh_params (server_pskcred, dh_params);
client_len = sizeof (sa_cli);
session = initialize_tls_session ();
sd = accept (listen_sd, (SA *) & sa_cli, &client_len);
success ("server: connection from %s, port %d\n",
inet_ntop (AF_INET, &sa_cli.sin_addr, topbuf,
sizeof (topbuf)), ntohs (sa_cli.sin_port));
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
ret = gnutls_handshake (session);
if (ret < 0)
{
close (sd);
gnutls_deinit (session);
fail ("server: Handshake has failed (%s)\n\n", gnutls_strerror (ret));
return;
}
success ("server: Handshake was completed\n");
/* see the Getting peer's information example */
/* print_info(session); */
i = 0;
for (;;)
{
memset (buffer, 0, MAX_BUF + 1);
ret = gnutls_record_recv (session, buffer, MAX_BUF);
if (ret == 0)
{
success ("server: Peer has closed the GNUTLS connection\n");
break;
}
else if (ret < 0)
{
fail ("server: Received corrupted data(%d). Closing...\n", ret);
break;
}
else if (ret > 0)
{
/* echo data back to the client
*/
gnutls_record_send (session, buffer, strlen (buffer));
}
}
/* do not wait for the peer to close the connection.
*/
gnutls_bye (session, GNUTLS_SHUT_WR);
close (sd);
gnutls_deinit (session);
close (listen_sd);
gnutls_psk_free_server_credentials (server_pskcred);
gnutls_dh_params_deinit (dh_params);
gnutls_global_deinit ();
success ("server: finished\n");
}
void
doit (void)
{
pid_t child;
server_start ();
if (error_count)
return;
child = fork ();
if (child < 0)
{
perror ("fork");
fail ("fork");
return;
}
if (child)
{
int status;
/* parent */
server ();
wait (&status);
}
else
client ();
}
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