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/*
* Copyright (C) 2004-2012 Free Software Foundation, Inc.
* Copyright (C) 2013 Adam Sampson <ats@offog.org>
*
* 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>
#if defined(_WIN32)
/* socketpair isn't supported on Win32. */
int main(int argc, char **argv)
{
exit(77);
}
#else
#include <string.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#if !defined(_WIN32)
#include <sys/wait.h>
#endif
#include <unistd.h>
#include <gnutls/gnutls.h>
#include "utils.h"
static void tls_log_func(int level, const char *str)
{
fprintf(stderr, "|<%d>| %s", level, str);
}
/* A very basic TLS client, with anonymous authentication.
*/
#define MAX_BUF 1024
#define MSG "Hello TLS"
static void client(int sd)
{
int ret, ii;
gnutls_session_t session;
char buffer[MAX_BUF + 1];
gnutls_anon_client_credentials_t anoncred;
/* Need to enable anonymous KX specifically. */
global_init();
gnutls_global_set_log_function(tls_log_func);
if (debug)
gnutls_global_set_log_level(4711);
gnutls_anon_allocate_client_credentials(&anoncred);
/* Initialize TLS session
*/
gnutls_init(&session, GNUTLS_CLIENT);
/* Use default priorities */
gnutls_priority_set_direct(session,
"NONE:+VERS-TLS-ALL:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ANON-DH",
NULL);
/* put the anonymous credentials to the current session
*/
gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);
gnutls_transport_set_int(session, sd);
/* Perform the TLS handshake
*/
ret = gnutls_handshake(session);
if (ret < 0) {
fail("client: Handshake failed\n");
gnutls_perror(ret);
goto end;
} else {
if (debug)
success("client: Handshake was completed\n");
}
ret = gnutls_dh_get_prime_bits(session);
if (ret < 512) {
fail("server: too small prime size: %d\n", ret);
}
ret = gnutls_dh_get_secret_bits(session);
if (ret < 256) {
fail("server: too small secret key size: %d\n", ret);
}
if (debug)
success("client: TLS version is: %s\n",
gnutls_protocol_get_name
(gnutls_protocol_get_version(session)));
gnutls_record_send(session, MSG, strlen(MSG));
ret = gnutls_record_recv(session, buffer, MAX_BUF);
if (ret == 0) {
if (debug)
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;
}
if (debug) {
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:
close(sd);
gnutls_deinit(session);
gnutls_anon_free_client_credentials(anoncred);
gnutls_global_deinit();
}
/* This is a sample TLS 1.0 echo server, for anonymous authentication only.
*/
#define MAX_BUF 1024
#define DH_BITS 1024
/* These are global */
gnutls_anon_server_credentials_t anoncred;
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_priority_set_direct(session,
"NONE:+VERS-TLS-ALL:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ANON-DH",
NULL);
gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);
gnutls_dh_set_prime_bits(session, DH_BITS);
return session;
}
static gnutls_dh_params_t dh_params;
static int generate_dh_params(void)
{
const gnutls_datum_t p3 = { (void *) 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);
}
int err, ret;
char topbuf[512];
gnutls_session_t session;
char buffer[MAX_BUF + 1];
int optval = 1;
static void server(int sd)
{
/* this must be called once in the program
*/
global_init();
gnutls_global_set_log_function(tls_log_func);
if (debug)
gnutls_global_set_log_level(4711);
gnutls_anon_allocate_server_credentials(&anoncred);
if (debug)
success("Launched, generating DH parameters...\n");
generate_dh_params();
gnutls_anon_set_server_dh_params(anoncred, dh_params);
session = initialize_tls_session();
gnutls_transport_set_int(session, 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;
}
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_dh_get_prime_bits(session);
if (ret < 512) {
fail("server: too small prime size: %d\n", ret);
}
ret = gnutls_dh_get_secret_bits(session);
if (ret < 256) {
fail("server: too small secret key size: %d\n", ret);
}
/* see the Getting peer's information example */
/* print_info(session); */
for (;;) {
memset(buffer, 0, MAX_BUF + 1);
ret = gnutls_record_recv(session, buffer, MAX_BUF);
if (ret == 0) {
if (debug)
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);
gnutls_anon_free_server_credentials(anoncred);
gnutls_dh_params_deinit(dh_params);
gnutls_global_deinit();
if (debug)
success("server: finished\n");
}
void doit(void)
{
pid_t child;
int sockets[2];
err = socketpair(AF_UNIX, SOCK_STREAM, 0, sockets);
if (err == -1) {
perror("socketpair");
fail("socketpair failed\n");
return;
}
child = fork();
if (child < 0) {
perror("fork");
fail("fork");
return;
}
if (child) {
int status;
/* parent */
server(sockets[0]);
wait(&status);
} else
client(sockets[1]);
}
#endif /* _WIN32 */
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