Matching an IP to a CIDR mask in PHP 5?

Question

I\'m looking for quick/simple method for matching a given IP4 dotted quad IP to a CIDR notation mask.

I have a bunch of IPs I need to see if they match a range of IP

Answer 1

Some function changed:

• split with explode

---

function cidr_match($ip, $range)
{
    list ($subnet, $bits) = explode('/', $range);
    $ip = ip2long($ip);
    $subnet = ip2long($subnet);
    $mask = -1 << (32 - $bits);
    $subnet &= $mask; 
    return ($ip & $mask) == $subnet;
}