xdp basic_firewall example for real use case ?

[vincentmli]

Hi,

I have been looking for XDP firewall example for a real use case to replace ipset adding/removing IPs/CIDRs for iptables based firewall. there is cilium ebpf-go library XDP example, I tried, not working for me since I am still relatively new on writing eBPF/XDP program from scratch, then I found dropbox goebpf XDP basic_firewall example, build it and run it, it works out of the box, and shows a good working example that I could extend.

Here is the changes I made to basic_firewall https://github.com/vincentmli/goebpf/tree/master/examples/xdp/basic_firewall, it is a real use case simple firewall example that users can easily try, especially the part that users can add or remove IPs/CIDRs on the pinned firewall map to allow or deny IPs/CIDRs at production firewall server. I think a simplified PR from my changes to the basic_firewall example would enable users to try in a real use case, would you accept such PR?

Thanks!