net-firewall/
fwbuilder

GUI management for iptables, PF, Cisco ASA/PIX/FWSM, Cisco router ACL and more

https://github.com/fwbuilder/fwbuilder

Pull Requests

If you also like to help the Gentoo project, you can consider sending a Pull Request via GitHub.
Before doing so, you might want to take a look at the wiki page.