nat on lo0 inet from 192.168.1.1 to any -> 10.0.0.1 port 500
nat on lo0 inet proto tcp from 192.168.1.2 to any -> 10.0.0.2 port 1000:5000
nat on lo0 inet proto udp from 192.168.1.3 to any -> 10.0.0.3 port 5000:1000
nat on lo0 inet proto udp from 192.168.1.4 to any -> 10.0.0.4 port 50000
nat on lo0 inet proto tcp from 192.168.1.2 to any -> 10.0.0.2 port 80:5000
nat on lo0 inet proto udp from 192.168.1.3 to any -> 10.0.0.3 port 5000:80