Converting iptables

[Sasa Stupar]

Hi!

I am thinking to change my old linux router to the freebsd one. The 
question is: how difficult is to convert iptables into ipfw rules?
I need some basic things with that router:
- internet gateway for LAN users
- packet filtering with MAC/IP address filtering
- port forwarding
- NAT onto same network so that LAN users can access web server which is 
on the LAN also

Is this all possible with ipfw?

Regards,
Sasa