Firewall Builder is multi-platform firewall configuration and management 
tool.  It consists of a GUI and set of policy compilers for various firewall 
platforms. Firewall Builder uses object-oriented approach, it helps the 
administrator maintain a database of network objects and allows policy 
editing using simple drag-and-drop operations. Firewall Builder currently 
supports iptables, ipfilter, OpenBSD PF, and Cisco PIX. 

This requires libfwbuilder, which is also available at SlackBuilds.org.