Blog | G5 Cyber Security

PHP: Block MAC Address

TL;DR

This guide shows you how to block a specific MAC address using PHP by checking it against a list and preventing access if found. This is useful for basic device control on your network, but remember this is server-side only – clients can spoof their MAC addresses.

Steps

  1. Create a Blocked MAC Address List
  2. First, you need a list of MAC addresses to block. This could be stored in a file, database, or directly within your PHP code (though that’s less flexible). For simplicity, we’ll use an array.

  3. Get the Client’s MAC Address
  4. This is the tricky part. PHP doesn’t have a built-in function to reliably get the client’s MAC address directly. You’ll need to rely on information passed by the client, which can be spoofed.

    Common methods (with caveats):

For demonstration purposes, let’s assume we receive the MAC address via a GET request parameter named mac_address.

  • Retrieve and Validate the MAC Address
  • Check Against the Blocked List
  • Now, compare the retrieved and validated client’s MAC address against your blocked list.

  • Complete Example
  • Putting it all together:

  • Important Considerations
  • Exit mobile version