/*
 * Copyright (C) 2004 Red Hat Inc.
 *
 * This program 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 2, or (at your option) any
 * later version.
 *
 * This program 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 this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Authors:
 *     Mark McLoughlin <mark@skynet.ie>
 */

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <gnutls/gnutls.h>

#undef DEBUG

#ifdef DEBUG
static void debug_log (int         level,
                       const char *str)
{
  fputs (str, stderr);
}
#endif

static int
do_client (int fd)
{
  gnutls_session                 session;
  static const int               kx_priority[] = { GNUTLS_KX_ANON_DH, 0 };
  gnutls_anon_server_credentials anon_cred;
  char                           buf[256];
  int                            n;
  int                            err;
  int                            retval = 1;

  gnutls_init (&session, GNUTLS_CLIENT);

  gnutls_set_default_priority (session);
  
  gnutls_kx_set_priority (session, kx_priority);

  gnutls_anon_allocate_client_credentials (&anon_cred);
  gnutls_credentials_set (session, GNUTLS_CRD_ANON, anon_cred);

  gnutls_transport_set_ptr (session, (gnutls_transport_ptr) fd);

  do {
    fprintf (stderr, "Trying to complete TLS handshake\n");
    err = gnutls_handshake (session);
  } while (err != GNUTLS_E_SUCCESS && !gnutls_error_is_fatal (err));
  
  if (err != GNUTLS_E_SUCCESS) {
    fprintf (stderr, "TLS Handshake failed: %s\n", gnutls_strerror (err));
    goto session_deinit_and_return;
  }

  while ((n = gnutls_record_recv (session, &buf, 256 - 1)) > 0) {
    buf [n] = '\0';
    printf ("%s\n", buf);
  }

  if (n < 0) {
    fprintf (stderr, "Error reading from server: %s\n", gnutls_strerror (n));
    retval = 0;
  } else if (n == 0) {
    fprintf (stderr, "Got EOF from recv\n");
  }

 session_deinit_and_return:
  do {
    fprintf (stderr, "Trying to complete shutdown\n");
    err = gnutls_bye (session, GNUTLS_SHUT_WR);
  } while (err != GNUTLS_E_SUCCESS && !gnutls_error_is_fatal (err));

  if (err != GNUTLS_E_SUCCESS) {
    fprintf (stderr, "TLS shutdown failed: %s\n", gnutls_strerror (err));
    retval = 0;
  }

  gnutls_anon_free_client_credentials (anon_cred);
  gnutls_deinit (session);

  return retval;
}

int main (int argc, char *argv[])
{
  int                sock;
  struct sockaddr_in servaddr;
  int                retval = 0;

  gnutls_global_init ();

#ifdef DEBUG
  gnutls_global_set_log_level (10);
  gnutls_global_set_log_function (debug_log);
#endif

  if ((sock = socket (AF_INET, SOCK_STREAM, 0)) == -1) {
    fprintf (stderr, "Error creating socket: %s\n", strerror (errno));
    retval = 1;
    goto global_deinit_and_return;
  }

  memset (&servaddr, 0, sizeof (struct sockaddr_in));
  servaddr.sin_family      = AF_INET;
  servaddr.sin_port        = htons (5899);
  servaddr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);

  if ((connect (sock, (struct sockaddr *) &servaddr, sizeof (struct sockaddr_in)) == -1)) {
    fprintf (stderr, "Error connecting to server: %s\n", strerror (errno));
    retval = 1;
    goto global_deinit_and_return;
  }

  if (do_client (sock))
    do_client (sock);

  close (sock);
  
 global_deinit_and_return:
  gnutls_global_deinit ();
  
  return retval;
}