DMZ ruleset: tighten

You may want to allow only what's needed:

pass in on $ext_if proto { tcp, udp } from any to $nameservers \
     port domain
pass in on $int_if proto { tcp, udp } from $localnet to $nameservers \
     port domain
pass out on $dmz_if proto { tcp, udp } from any to $nameservers \
     port domain
pass in on $ext_if proto tcp from any to $webserver port $webports
pass in on $int_if proto tcp from $localnet to $webserver \
     port $webports
pass out on $dmz_if proto tcp from any to $webserver port $webports
pass in log on $ext_if proto tcp from any to $mailserver port smtp
pass in log on $int_if proto tcp from $localnet to $mailserver \
     port $email
pass out log on $dmz_if proto tcp from any to $mailserver port smtp
pass in on $dmz_if from $mailserver to any port smtp
pass out log on $ext_if proto tcp from $mailserver to any port smtp