private function verify_port(int $port=null, string $proto) {
		if (!$port)
			return $port;
		if ($port < 0 || $port > pow(2, 16))
			return null;
		if ($port == 80 && $proto == 'http')
			return null;
		if ($port == 443 && $proto == 'https')
			return null;
		return $port;
	}