BitTorrent: Download not starting
I am trying to implement a bittorrent tracker in Laravel. However, I am stuck at the moment as the download won't start. There is one peer which it appears to be seeding and I am 100% sure that it is connectable. But, when I run a second client on a different machine, the download won't start. It is stuck at "Connecting to peers" (uTorrent).
From the tracker I am sending the following response when the client makes an announce:
d8:intervali1000e12:min intervali300e5:peers18:�ؤ�i�ؑ�XÚJU�6e
In the downloading client I have the following data:
Here's my announce code:
<?php
namespace App\Http\Controllers\Announce;
use App\Helpers\BencodeHelper;
use App\Models\Peer;
use App\Models\PeerTorrent;
use App\Models\Torrent;
use App\Models\User;
use Illuminate\Http\Request;
use Illuminate\Http\Response;
use Illuminate\Routing\Controller;
use Illuminate\Support\Facades\Input;
use Illuminate\Support\Facades\Log;
class AnnounceController extends Controller
{
const __INTERVAL = 1000;
const __TIMEOUT = 120;
const __INTERVAL_MIN = 60;
const __MAX_PPR = 20;
public function announce(Request $request)
{
Log::info($request->fullUrl());
$status = 200;
$content = "";
$passkey = Input::get('passkey');
$peer_id = Input::get('peer_id');
$port = Input::get('port');
$info_hash = Input::get('info_hash');
$downloaded = Input::get('uploaded') ? intval(Input::get('uploaded')) : 0;
$uploaded = Input::get('uploaded') ? intval(Input::get('uploaded')) : 0;
$left = Input::get('left') ? intval(Input::get('left')) : 0;
$compact = Input::get('compact') ? intval(Input::get('compact')) : 0;
$no_peer_id = Input::get('no_peer_id') ? intval(Input::get('no_peer_id')) : 0;
$ipAddress = '';
// Check for X-Forwarded-For headers and use those if found
if (isset($_SERVER['HTTP_X_FORWARDED_FOR']) && ('' !== trim($_SERVER['HTTP_X_FORWARDED_FOR']))) {
$ipAddress = (trim($_SERVER['HTTP_X_FORWARDED_FOR']));
} else {
if (isset($_SERVER['REMOTE_ADDR']) && ('' !== trim($_SERVER['REMOTE_ADDR']))) {
$ipAddress = (trim($_SERVER['REMOTE_ADDR']));
}
}
$port = $_SERVER['REMOTE_PORT'];
/*if(!$port || !ctype_digit($port) || intval($port) < 1 || intval($port) > 65535)
{
$content = BencodeHelper::track("Invalid client port.");
$status = 401;
return (new Response(AnnounceController::track($content), $status))
->header('Content-Type', $value);
}
if ($port == 999 && substr($peer_id, 0, 10) == '-TO0001-XX') {
die("d8:completei0e10:incompletei0e8:intervali600e12:min intervali60e5:peersld2:ip12:72.14.194.184:port3:999ed2:ip11:72.14.194.14:port3:999ed2:ip12:72.14.194.654:port3:999eee");
}*/
if (!$passkey) {
$content = BencodeHelper::track("Missing passkey.");
$status = 401;
return (new Response(AnnounceController::track($content), $status))
->header('Content-Type', $value);
}
$torrent = Torrent::getByInfoHash(sha1($info_hash));
if (!$torrent || $torrent == null) {
$content = "Torrent not registered with this tracker.";
$status = 404;
return (new Response(AnnounceController::track($content), $status))
->header('Content-Type', $value);
}
$user = User::has('passkeys', '=', $passkey)->get();
if ($user == null) {
$content = BencodeHelper::track("Invalid passkey.");
$status = 401;
return (new Response(AnnounceController::track($content), $status))
->header('Content-Type', $value);
}
$peer = Peer::getByHashAndPasskey(bin2hex($peer_id), $passkey);
if ($peer == null) {
$peer = Peer::create([
'hash' => bin2hex($peer_id),
'user_agent' => $_SERVER['HTTP_USER_AGENT'],
'ip_address' => $ipAddress,
'passkey' => $passkey,
'port' => $port
]);
}
if (!$info_hash || strlen($info_hash) != 20) {
$content = BencodeHelper::track("Invalid info_hash.");
$status = 401;
return (new Response(AnnounceController::track($content), $status))
->header('Content-Type', $value);
}
$peer_torrent = PeerTorrent::getByPeerAndTorrent($peer, $torrent);
if ($peer_torrent == null) {
$peer_torrent = PeerTorrent::create([
'peer_id' => $peer->id,
'torrent_id' => $torrent->id,
'uploaded' => $uploaded,
'downloaded' => $downloaded,
'left' => $left,
'stopped' => false
]);
} else {
$peer_torrent->uploaded = $uploaded;
$peer_torrent->downloaded = $downloaded;
$peer_torrent->left = $left;
$peer_torrent->save();
}
$seeders = $torrent->getSeedersCount();
$leechers = $torrent->getLeechersCount();
$resp = "";
if ($compact != 1) {
$resp = "d" . $this->benc_str("interval") . "i" . AnnounceController::__INTERVAL . "e" . $this->benc_str("peers") . "l";
} else {
$resp = "d" . $this->benc_str("interval") . "i" . AnnounceController::__INTERVAL . "e" . $this->benc_str("min interval") . "i" . 300 . "e5:" . "peers";
}
$peer = array();
$peer_num = 0;
foreach ($torrent->getPeersArray() as $row) {
if ($compact != 1) {
if ($row["peer_id"] === $peer->hash) {
continue;
}
$resp .= "d" . $this->benc_str("ip") . $this->benc_str($row['ip']);
if ($no_peer_id == 0) {
$resp .= $this->benc_str("peer id") . $this->benc_str($row["peer_id"]);
}
$resp .= $this->benc_str("port") . "i" . $row["port"] . "e" . "e";
} else {
$peer_ip = explode('.', $row["ip"]);
$peer_ip = pack("C*", $peer_ip[0], $peer_ip[1], $peer_ip[2], $peer_ip[3]);
$peer_port = pack("n*", (int)$row["port"]);
$time = intval((time() % 7680) / 60);
if ($left == 0) {
$time += 128;
}
$time = pack("C", $time);
$peer[] = $time . $peer_ip . $peer_port;
$peer_num++;
}
}
if ($compact != 1) {
$resp .= "ee";
} else {
$o = "";
for ($i = 0; $i < $peer_num; $i++) {
$o .= substr($peer[$i], 1, 6);
}
$resp .= strlen($o) . ':' . $o . 'e';
}
$this->benc_resp_raw($resp);
}
public function benc_resp($d)
{
return $this->benc_resp_raw($this->benc(array('type' => 'dictionary', 'value' => $d)));
}
public function benc_resp_raw($x)
{
header("Content-Type: text/plain");
header("Pragma: no-cache");
if ($_SERVER['HTTP_ACCEPT_ENCODING'] == 'gzip') {
header("Content-Encoding: gzip");
echo gzencode($x, 9, FORCE_GZIP);
} else {
echo $x;
}
}
function benc($obj)
{
if (!is_array($obj) || !isset($obj["type"]) || !isset($obj["value"]))
return;
$c = $obj["value"];
switch ($obj["type"]) {
case "string":
return $this->benc_str($c);
case "integer":
return $this->benc_int($c);
case "list":
return $this->benc_list($c);
case "dictionary":
return $this->benc_dict($c);
default:
return;
}
}
public function benc_str($s)
{
return strlen($s) . ":$s";
}
public function benc_int($i)
{
return "i" . $i . "e";
}
public function benc_list($a)
{
$s = "l";
foreach ($a as $e) {
$s .= $this->benc($e);
}
$s .= "e";
return $s;
}
public function benc_dict($d)
{
$s = "d";
$keys = array_keys($d);
sort($keys);
foreach ($keys as $k) {
$v = $d[$k];
$s .= $this->benc_str($k);
$s .= $this->benc($v);
}
$s .= "e";
return $s;
}
public function hex2bin($hex)
{
$r = '';
for ($i = 0; $i < strlen($hex); $i += 2) {
$r .= chr(hexdec($hex{$i} . $hex{($i + 1)}));
}
return $r;
}
}
I am not quite sure what am I missing here.
Maybe it's because you constantly set
->header('Content-Type', $value);
without ever setting $value? So the "Announce-Response" is malformed?