WiFi IP filtering?

Typically a WiFi host, or router, will actually assign each client an individual IP address. However, most WiFi routers and access points are either firewalls or connected to a firewall. A firewall can be configured to filter traffic based on IP address, however I don't see that happening at the WiFi level.

"The wifi driver receives the packets, pass them to the hardware to decrypt it and driver gets the real data packets, and it can read the IP header. If you want to filter out some client like MAC address filering, you must modify the wifi driver yourself and add some code to do this thing.

Hardware RX -> wifi driver -> IP filter function -> Upper layer.

But it violates the 4-layer module, so it is not suggested to do this work.
You need also add a user space ioctl interface in wifi driver to control it."