This is what firewall rules from pfSense look like:
<filter> <rule> <type>reject</type> <interface>wan</interface> <max-src-nodes/> <max-src-states/> <statetimeout/> <statetype>keep state</statetype> <os/> <protocol>tcp</protocol> <source> <address>192.0.2.0</address> </source> <destination> <any/> </destination> <log/> <descr></descr> </rule> </filter>
I'm working on a new project which will work with this type of data.