Online PHP editor | output for bQmro

<?php /** * Check if a client IP is in our Server subnet * * @param string $client_ip * @param string $server_ip * @return boolean */ function clientInSameSubnet($client_ip=false,$server_ip=false) { if (!$client_ip) $client_ip = $_SERVER['REMOTE_ADDR']; if (!$server_ip) $server_ip = $_SERVER['SERVER_ADDR']; // Extract broadcast and netmask from ifconfig if (!($p = popen("ifconfig","r"))) return false; $out = ""; while(!feof($p)) $out .= fread($p,1024); fclose($p); // This is because the php.net comment function does not // allow long lines. $match = "/^.*".$server_ip; $match .= ".*Bcast:(\d{1,3}\.\d{1,3}i\.\d{1,3}\.\d{1,3}).*"; $match .= "Mask:(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})$/im"; if (!preg_match($match,$out,$regs)) return false; $bcast = ip2long($regs[1]); $smask = ip2long($regs[2]); $ipadr = ip2long($client_ip); $nmask = $bcast & $smask; return (($ipadr & $smask) == ($nmask & $smask)); } ?>