<?php

// License Information /////////////////////////////////////////////////////////////////////////////

/*
 * PeerTracker - OpenSource BitTorrent Tracker
 * Revision - $Id: announce.php 161 2010-01-20 17:49:50Z trigunflame $
 * Copyright (C) 2009 PeerTracker Team
 *
 * PeerTracker 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.
 *
 * PeerTracker 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 PeerTracker.  If not, see <http://www.gnu.org/licenses/>.
 */

// Enviroment Runtime //////////////////////////////////////////////////////////////////////////////

// error level
error_reporting(E_ERROR | E_PARSE);
//error_reporting(E_ALL & ~E_WARNING);
//error_reporting(E_ALL | E_STRICT | E_DEPRECATED);

// ignore disconnects
ignore_user_abort(true);

// load tracker core
require './tracker.postgresql.php';

// Verify Request //////////////////////////////////////////////////////////////////////////////////

// strip auto-escaped data
if (get_magic_quotes_gpc())
{
	$_GET['info_hash'] = stripslashes($_GET['info_hash']);
	$_GET['peer_id'] = stripslashes($_GET['peer_id']);
}

// 20-bytes - info_hash
// sha-1 hash of torrent metainfo
if (!isset($_GET['info_hash']) || strlen($_GET['info_hash']) != 20) exit;

// 20-bytes - peer_id
// client generated unique peer identifier
if (!isset($_GET['peer_id']) || strlen($_GET['peer_id']) != 20) exit;

// integer - port
// port the client is accepting connections from
if (!(isset($_GET['port']) && is_numeric($_GET['port']))) tracker_error('client listening port is invalid');

// integer - left
// number of bytes left for the peer to download
if (isset($_GET['left']) && is_numeric($_GET['left'])) $_SERVER['tracker']['seeding'] = ($_GET['left'] > 0 ? 0 : 1); else tracker_error('client data left field is invalid');

// integer boolean - compact - optional
// send a compact peer response
// http://bittorrent.org/beps/bep_0023.html
if (!isset($_GET['compact']) || $_SERVER['tracker']['force_compact']) $_GET['compact'] = 1; else $_GET['compact'] += 0;

// integer boolean - no_peer_id - optional
// omit peer_id in dictionary announce response
if (!isset($_GET['no_peer_id'])) $_GET['no_peer_id'] = 0; else $_GET['no_peer_id'] += 0;

// string - ip - optional
// ip address the peer requested to use
if (isset($_GET['ip']) && $_SERVER['tracker']['external_ip'])
{
	// dotted decimal only
	$_GET['ip'] = trim($_GET['ip'],'::ffff:');
	if (!ip2long($_GET['ip'])) tracker_error('invalid ip, dotted decimal only');
}
// set ip to connected client
elseif (isset($_SERVER['REMOTE_ADDR'])) $_GET['ip'] = trim($_SERVER['REMOTE_ADDR'],'::ffff:');
// cannot locate suitable ip, must abort
else tracker_error('could not locate clients ip');

// integer - numwant - optional
// number of peers that the client has requested
if (!isset($_GET['numwant'])) $_GET['numwant'] = $_SERVER['tracker']['default_peers'];
elseif (($_GET['numwant']+0) > $_SERVER['tracker']['max_peers']) $_GET['numwant'] = $_SERVER['tracker']['max_peers'];
else $_GET['numwant'] += 0;

// Handle Request //////////////////////////////////////////////////////////////////////////////////

// open database
peertracker::open();

// make info_hash & peer_id SQL friendly
$_GET['info_hash'] = pg_escape_bytea(peertracker::$db, $_GET['info_hash']);
$_GET['peer_id']   = pg_escape_bytea(peertracker::$db, $_GET['peer_id']);

// announce peers
peertracker::peers();

// track client
peertracker::event();

// garbage collection
peertracker::clean();

// close database
peertracker::close();

?>