/**
* {@inheritdoc}
*/
public function checkVisitor(Visitor $visitor)
{
if ($visitor->getRequestMethod() == 'POST') {
if ($result = $this->checkPostRequest($visitor)) {
return $result;
}
}
return CheckInterface::RESULT_OKAY;
}
/**
* Analyzes the request headers.
*
* @param \FlameCore\Gatekeeper\Visitor $visitor
* @return bool|string
*/
protected function checkHeaders(Visitor $visitor)
{
$headers = $visitor->getRequestHeaders();
$uastring = $visitor->getUserAgent()->getUserAgentString();
if ($visitor->getRequestMethod() != 'POST' && empty($uastring)) {
return 'f9f2b8b9';
}
// 'Range:' field exists and begins with 0. Real user-agents do not start ranges at 0. (Also blocks whois.sc bot. No big loss.)
// Exceptions: MT (not fixable); LJ (refuses to fix; may be blocked again in the future); Facebook
if ($this->settings['strict'] && $headers->has('Range') && strpos($headers->get('Range'), '=0-') !== false) {
if (strncmp($uastring, 'MovableType', 11) && strncmp($uastring, 'URI::Fetch', 10) && strncmp($uastring, 'php-openid/', 11) && strncmp($uastring, 'facebookexternalhit', 19)) {
return '7ad04a8a';
}
}
// Content-Range is a response header, not a request header
if ($headers->has('Content-Range')) {
return '7d12528e';
}
// pinappleproxy is used by referrer spammers
if ($headers->has('Via')) {
if (stripos($headers->get('Via'), 'pinappleproxy') !== false || stripos($headers->get('Via'), 'PCNETSERVER') !== false || stripos($headers->get('Via'), 'Invisiware') !== false) {
return '939a6fbb';
}
}
// 'TE:' if present must have 'Connection: TE' (RFC 2616 14.39)
// Blocks Microsoft ISA Server 2004 in strict mode. Contact Microsoft to obtain a hotfix.
if ($this->settings['strict'] && $headers->has('Te')) {
if (!preg_match('/\\bTE\\b/', $headers->get('Connection'))) {
return '582ec5e4';
}
}
// Analyze the Connection header if it exists
if ($headers->has('Connection') && ($result = $this->checkConnectionHeader($headers->get('Connection')))) {
return $result;
}
// Headers which are not seen from normal user agents; only malicious bots
if ($headers->has('X-Aaaaaaaaaaaa') || $headers->has('X-Aaaaaaaaaa')) {
return 'b9cc1d86';
}
// 'Proxy-Connection' does not exist and should never be seen in the wild.
// - http://lists.w3.org/Archives/Public/ietf-http-wg-old/1999JanApr/0032.html
// - http://lists.w3.org/Archives/Public/ietf-http-wg-old/1999JanApr/0040.html
if ($this->settings['strict'] && $headers->has('Proxy-Connection')) {
return 'b7830251';
}
// Analyze the Referer header if it exists
if ($headers->has('Referer') && ($result = $this->checkRefererHeader($headers->get('Referer')))) {
return $result;
}
return false;
}
