/**
* Pick a random dir authority to query and perform the HTTP request for directory info
*
* @param string $uri Uri to request
* @param string $directoryServer IP and port of the directory to query
* @throws \Exception No authorities responded
* @return \Dapphp\TorUtils\ProtocolReply The reply from the directory authority
*/
private function _request($uri, $directoryServer = null)
{
reset($this->_serverList);
do {
// pick a server from the list, it is randomized in __construct
$server = $this->getNextServer();
if ($server === false) {
throw new \Exception('No more directory servers available to query');
}
list($host, $port) = @explode(':', $server);
if (!$port) {
$port = 80;
}
$fp = fsockopen($host, $port, $errno, $errstr, $this->_connectTimeout);
if (!$fp) {
continue;
}
$request = $this->_getHttpRequest('GET', $host, $uri);
fwrite($fp, $request);
$response = '';
while (!feof($fp)) {
$response .= fgets($fp);
}
fclose($fp);
list($headers, $body) = explode("\r\n\r\n", $response, 2);
$headers = $this->_parseHttpResponseHeaders($headers);
if ($headers['status_code'] !== '200') {
throw new \Exception(sprintf('Directory returned a negative response code to request. %s %s', $headers['status_code'], $headers['message']));
}
$encoding = isset($headers['headers']['content-encoding']) ? $headers['headers']['content-encoding'] : null;
if ($encoding == 'deflate') {
if (!function_exists('gzuncompress')) {
throw new \Exception('Directory response was gzip compressed but PHP does not have zlib support enabled');
}
$body = gzuncompress($body);
if ($body === false) {
throw new \Exception('Failed to inflate response data');
}
} else {
if ($encoding == 'identity') {
// nothing to do
} else {
throw new \Exception('Directory sent response in an unknown encoding: ' . $encoding);
}
}
break;
} while (true);
$reply = new ProtocolReply();
$reply->appendReplyLine(sprintf('%s %s', $headers['status_code'], $headers['message']));
$reply->appendReplyLines(explode("\n", $body));
return $reply;
}
