pass in on ed0(!) proto tcp from 127.0.0.1/32 to 127.0.0.1/32 port = 23 flags S/SA
block in on lo0(!) proto tcp from any to any flags A/0xff
pass in on lo0(!) proto tcp from any to any flags /SPA
block in on lo0(!) proto tcp from any to any flags 0x80/A