rfc6455/Version/Hixie76.php
2013-03-31 14:02:10 -04:00

116 lines
4.0 KiB
PHP

<?php
namespace Ratchet\WebSocket\Version;
use Ratchet\ConnectionInterface;
use Ratchet\MessageInterface;
use Ratchet\WebSocket\Version\Hixie76\Connection;
use Guzzle\Http\Message\RequestInterface;
use Guzzle\Http\Message\Response;
use Ratchet\WebSocket\Version\Hixie76\Frame;
/**
* FOR THE LOVE OF BEER, PLEASE PLEASE PLEASE DON'T allow the use of this in your application!
* Hixie76 is bad for 2 (there's more) reasons:
* 1) The handshake is done in HTTP, which includes a key for signing in the body...
* BUT there is no Length defined in the header (as per HTTP spec) so the TCP buffer can't tell when the message is done!
* 2) By nature it's insecure. Google did a test study where they were able to do a
* man-in-the-middle attack on 10%-15% of the people who saw their ad who had a browser (currently only Safari) supporting the Hixie76 protocol.
* This was exploited by taking advantage of proxy servers in front of the user who ignored some HTTP headers in the handshake
* The Hixie76 is currently implemented by Safari
* @link http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-76
*/
class Hixie76 implements VersionInterface {
/**
* {@inheritdoc}
*/
public function isProtocol(RequestInterface $request) {
return !(null === $request->getHeader('Sec-WebSocket-Key2', true));
}
/**
* {@inheritdoc}
*/
public function getVersionNumber() {
return 0;
}
/**
* @param \Guzzle\Http\Message\RequestInterface $request
* @return \Guzzle\Http\Message\Response
* @throws \UnderflowException If there hasn't been enough data received
*/
public function handshake(RequestInterface $request) {
$body = substr($request->getBody(), 0, 8);
if (8 !== strlen($body)) {
throw new \UnderflowException("Not enough data received to issue challenge response");
}
$challenge = $this->sign($request->getHeader('Sec-WebSocket-Key1', true), $request->getHeader('Sec-WebSocket-Key2', true), $body);
$headers = array(
'Upgrade' => 'WebSocket'
, 'Connection' => 'Upgrade'
, 'Sec-WebSocket-Origin' => $request->getHeader('Origin', true)
, 'Sec-WebSocket-Location' => 'ws://' . $request->getHeader('Host', true) . $request->getPath()
);
$response = new Response(101, $headers, $challenge);
$response->setStatus(101, 'WebSocket Protocol Handshake');
return $response;
}
/**
* {@inheritdoc}
*/
public function upgradeConnection(ConnectionInterface $conn, MessageInterface $coalescedCallback) {
$upgraded = new Connection($conn);
if (!isset($upgraded->WebSocket)) {
$upgraded->WebSocket = new \StdClass;
}
$upgraded->WebSocket->coalescedCallback = $coalescedCallback;
return $upgraded;
}
public function onMessage(ConnectionInterface $from, $data) {
$overflow = '';
if (!isset($from->WebSocket->frame)) {
$from->WebSocket->frame = $this->newFrame();
}
$from->WebSocket->frame->addBuffer($data);
if ($from->WebSocket->frame->isCoalesced()) {
$overflow = $from->WebSocket->frame->extractOverflow();
$parsed = $from->WebSocket->frame->getPayload();
unset($from->WebSocket->frame);
$from->WebSocket->coalescedCallback->onMessage($from, $parsed);
unset($from->WebSocket->frame);
}
if (strlen($overflow) > 0) {
$this->onMessage($from, $overflow);
}
}
public function newFrame() {
return new Frame;
}
public function generateKeyNumber($key) {
return preg_replace('[\D]', '', $key) / substr_count($key, ' ');
}
protected function sign($key1, $key2, $code) {
return md5(
pack('N', $this->generateKeyNumber($key1))
. pack('N', $this->generateKeyNumber($key2))
. $code
, true);
}
}