| log in proto tcp from any port > 0 to any |
| log in proto tcp from any to any port > 0 |
| pass in proto 6 from any port != 0 to any port 0 >< 65535 |
| pass in proto 17 from localhost port > 32000 to localhost port < 29000 |
| block in proto udp from any port != \ntp to any port < echo |
| block in proto tcp from any port = smtp to any port > 25 |
| pass in proto tcp/udp from any port 1 >< 3 to any port 1 <> 3 |
| pass in proto tcp/udp from any port 2:2 to any port 10:20 |
| pass in log first quick proto tcp from any port > 1023 to any port = 1723 flags S keep state |