IP Address Subnet Sniffer: Determine if an IP address belongs to a subnetwork

This class can be used to determine wether a given IP address belongs to a given list of subnetworks.

The class takes an array of subnetwork masks to be checked in the form of strings with decimal numbers seperated dots .

Then the class can check whether a given IP address belongs to any of the specified subnetworks by applying the respective masks.

This class was created to emulate the "Deny from x.x.x.x" directive for Apache (nd other servers -- for example, Samba uses a similar format for allowing/denying access to a range of IP addresses). I needed a way to deny/allow access to a range of IP addresses but, for technical reasons, I could not use a .htaccess file, and had to do the IP address processing within the PHP script itself.

For example, you can emulate the line "Deny from 192.168.0.0/24" by supplying the string "192.168.0.0/24" to the class. To see exactly how to do this, see the documentation within the class file itself.