Openwrt block internet based on MAC address

Installing and Using OpenWrt
1

Hello,

I have openwrt (rpi4) as my main router and another AP flashed openwrt as my wireless access point.
All my wireless devices connect to wireless access point.
How to block internet to certain devices based on their MAC address? Is this to be done at main openwrt router or at wireless access point?

Thanks

2

Look at OpenNDS, consider MAC addresses being quite random nowadays.