/*
 * This file is part of the Nice GLib ICE library.
 *
 * (C) 2008-2009 Collabora Ltd.
 *  Contact: Youness Alaoui
 * (C) 2007-2009 Nokia Corporation. All rights reserved.
 *  Contact: Rémi Denis-Courmont
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Nice GLib ICE library.
 *
 * The Initial Developers of the Original Code are Collabora Ltd and Nokia
 * Corporation. All Rights Reserved.
 *
 * Contributors:
 *   Youness Alaoui, Collabora Ltd.
 *   Olivier Crete, Collabora Ltd.
 *   Kai Vehmanen, Nokia
 *
 * Alternatively, the contents of this file may be used under the terms of the
 * the GNU Lesser General Public License Version 2.1 (the "LGPL"), in which
 * case the provisions of LGPL are applicable instead of those above. If you
 * wish to allow use of your version of this file only under the terms of the
 * LGPL and not to allow others to use your version of this file under the
 * MPL, indicate your decision by deleting the provisions above and replace
 * them with the notice and other provisions required by the LGPL. If you do
 * not delete the provisions above, a recipient may use your version of this
 * file under either the MPL or the LGPL.
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>

#include "utils.h"

size_t stun_padding (size_t l)
{
  return (4 - (l & 3)) & 3;
}

size_t stun_align (size_t l)
{
  return (l + 3) & ~3;
}


uint16_t stun_getw (const uint8_t *ptr)
{
  return ((ptr)[0] << 8) | ptr[1];
}


void *stun_setw (uint8_t *ptr, uint16_t value)
{
  *ptr++ = value >> 8;
  *ptr++ = value & 0xff;
  return ptr;
}


void stun_set_type (uint8_t *h, StunClass c, StunMethod m)
{
/*   assert (c < 4); */
/*   assert (m < (1 << 12)); */

  h[0] = (c >> 1) | ((m >> 6) & 0x3e);
  h[1] = ((c << 4) & 0x10) | ((m << 1) & 0xe0) | (m & 0x0f);

/*   assert (stun_getw (h) < (1 << 14)); */
/*   assert (stun_get_class (h) == c); */
/*   assert (stun_get_method (h) == m); */
}


StunMessageReturn stun_xor_address (const StunMessage *msg,
    struct sockaddr_storage *addr, socklen_t addrlen,
    uint32_t magic_cookie)
{
  union {
    struct sockaddr_storage *addr;
    struct sockaddr_in *in;
    struct sockaddr_in6 *in6;
  } addr_ptr;

  addr_ptr.addr = addr;

  switch (addr->ss_family)
  {
    case AF_INET:
    {
      struct sockaddr_in *ip4 = addr_ptr.in;
      if ((size_t) addrlen < sizeof (*ip4))
        return STUN_MESSAGE_RETURN_INVALID;

      ip4->sin_port ^= htons (magic_cookie >> 16);
      ip4->sin_addr.s_addr ^= htonl (magic_cookie);
      return STUN_MESSAGE_RETURN_SUCCESS;
    }

    case AF_INET6:
    {
      struct sockaddr_in6 *ip6 = addr_ptr.in6;
      unsigned short i;

      if ((size_t) addrlen < sizeof (*ip6))
        return STUN_MESSAGE_RETURN_INVALID;

      ip6->sin6_port ^= htons (magic_cookie >> 16);
      for (i = 0; i < 16; i++)
        ip6->sin6_addr.s6_addr[i] ^= msg->buffer[4 + i];
      return STUN_MESSAGE_RETURN_SUCCESS;
    }

    default:
      return STUN_MESSAGE_RETURN_UNSUPPORTED_ADDRESS;
  }
}