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/*
* Copyright (C) 2008, 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
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <gnutls/gnutls.h>
#include "utils.h"
static void
tls_log_func (int level, const char *str)
{
fprintf (stderr, "|<%d>| %s", level, str);
}
char *to_server;
size_t to_server_len;
char *to_client;
size_t to_client_len;
static ssize_t
client_pull (gnutls_transport_ptr_t tr, void *data, size_t len)
{
success ("client_pull len %d has %d\n", (int)len, (int)to_client_len);
if (to_client_len < len)
{
gnutls_transport_set_global_errno (EAGAIN);
return -1;
}
memcpy (data, to_client, len);
memmove (to_client, to_client + len, to_client_len - len);
to_client_len -= len;
return len;
}
static ssize_t
client_push (gnutls_transport_ptr_t tr, const void *data, size_t len)
{
size_t newlen = to_server_len + len;
char *tmp;
success ("client_push len %d has %d\n", (int)len, (int)to_server_len);
hexprint (data, len);
tmp = realloc (to_server, newlen);
if (!tmp)
{
fail ("Memory allocation failure...\n");
exit (1);
}
to_server = tmp;
memcpy (to_server + to_server_len, data, len);
to_server_len = newlen;
return len;
}
static ssize_t
server_pull (gnutls_transport_ptr_t tr, void *data, size_t len)
{
success ("server_pull len %d has %d\n", (int)len, (int)to_server_len);
if (to_server_len < len)
{
gnutls_transport_set_global_errno (EAGAIN);
return -1;
}
memcpy (data, to_server, len);
memmove (to_server, to_server + len, to_server_len - len);
to_server_len -= len;
return len;
}
static ssize_t
server_push (gnutls_transport_ptr_t tr, const void *data, size_t len)
{
size_t newlen = to_client_len + len;
char *tmp;
success ("server_push len %d has %d\n", (int)len, (int)to_client_len);
hexprint (data, len);
tmp = realloc (to_client, newlen);
if (!tmp)
{
fail ("Memory allocation failure...\n");
exit (1);
}
to_client = tmp;
memcpy (to_client + to_client_len, data, len);
to_client_len = newlen;
return len;
}
#define MAX_BUF 1024
#define MSG "Hello TLS"
void
doit (void)
{
/* Server stuff. */
gnutls_anon_server_credentials_t s_anoncred;
const gnutls_datum_t p3 = { (char *) pkcs3, strlen (pkcs3) };
static gnutls_dh_params_t dh_params;
gnutls_session_t server;
int sret = GNUTLS_E_AGAIN;
/* Client stuff. */
gnutls_anon_client_credentials_t c_anoncred;
gnutls_session_t client;
int n, cret = GNUTLS_E_AGAIN;
/* Need to enable anonymous KX specifically. */
const int kx_prio[] = { GNUTLS_KX_ANON_DH, 0 };
char buffer[MAX_BUF + 1];
ssize_t ns;
int ret;
/* General init. */
gnutls_global_init ();
gnutls_global_set_log_function (tls_log_func);
if (debug)
gnutls_global_set_log_level (4711);
/* Init server */
gnutls_anon_allocate_server_credentials (&s_anoncred);
gnutls_dh_params_init (&dh_params);
gnutls_dh_params_import_pkcs3 (dh_params, &p3, GNUTLS_X509_FMT_PEM);
gnutls_anon_set_server_dh_params (s_anoncred, dh_params);
gnutls_init (&server, GNUTLS_SERVER);
gnutls_set_default_priority (server);
gnutls_kx_set_priority (server, kx_prio);
gnutls_credentials_set (server, GNUTLS_CRD_ANON, s_anoncred);
gnutls_dh_set_prime_bits (server, 1024);
gnutls_transport_set_push_function (server, server_push);
gnutls_transport_set_pull_function (server, server_pull);
/* Init client */
gnutls_anon_allocate_client_credentials (&c_anoncred);
gnutls_init (&client, GNUTLS_CLIENT);
gnutls_set_default_priority (client);
gnutls_kx_set_priority (client, kx_prio);
gnutls_credentials_set (client, GNUTLS_CRD_ANON, c_anoncred);
gnutls_transport_set_push_function (client, client_push);
gnutls_transport_set_pull_function (client, client_pull);
do
{
if (cret == GNUTLS_E_AGAIN)
{
success ("loop invoking client:\n");
cret = gnutls_handshake (client);
success ("client %d: %s\n", cret, gnutls_strerror (cret));
}
if (sret == GNUTLS_E_AGAIN)
{
success ("loop invoking server:\n");
sret = gnutls_handshake (server);
success ("server %d: %s\n", sret, gnutls_strerror (sret));
}
}
while (cret == GNUTLS_E_AGAIN || sret == GNUTLS_E_AGAIN);
success ("Handshake established\n");
ns = gnutls_record_send (client, MSG, strlen (MSG));
success ("client: sent %d\n", (int)ns);
ret = gnutls_record_recv (server, buffer, MAX_BUF);
if (ret == 0)
fail ("server: didn't receive any data\n");
else if (ret < 0)
fail ("server: error: %s\n", gnutls_strerror (ret));
else
{
printf ("server: received %d: ", ret);
for (n = 0; n < ret; n++)
fputc (buffer[n], stdout);
fputs ("\n", stdout);
}
ns = gnutls_record_send (server, MSG, strlen (MSG));
success ("server: sent %d\n", (int)ns);
ret = gnutls_record_recv (client, buffer, MAX_BUF);
if (ret == 0)
{
fail ("client: Peer has closed the TLS connection\n");
}
else if (ret < 0)
{
fail ("client: Error: %s\n", gnutls_strerror (ret));
}
else
{
printf ("client: received %d: ", ret);
for (n = 0; n < ret; n++)
fputc (buffer[n], stdout);
fputs ("\n", stdout);
}
gnutls_bye (client, GNUTLS_SHUT_RDWR);
gnutls_bye (server, GNUTLS_SHUT_RDWR);
gnutls_deinit (client);
gnutls_deinit (server);
free (to_server);
free (to_client);
gnutls_anon_free_client_credentials (c_anoncred);
gnutls_anon_free_server_credentials (s_anoncred);
gnutls_dh_params_deinit (dh_params);
gnutls_global_deinit ();
}
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