*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:log-smtp - [0:0]
-A INPUT -p udp -m udp --dport 161 ! -s 18.0.0.0/8 -j REJECT
-A OUTPUT -p tcp -m tcp --dport 25 --syn -j log-smtp
-A log-smtp -m owner --uid-owner postfix -j RETURN
-A log-smtp -m owner --uid-owner nrpe -o lo -j RETURN
# 537644531=scripts (for heartbeat)
-A log-smtp -m owner --uid-owner 537644531 -o lo -j RETURN
-A log-smtp -j LOG --log-prefix "SMTP " --log-uid
-A log-smtp -o lo -j RETURN
# 18.9.28.100=outgoing.mit.edu
-A log-smtp -d 18.9.28.100 -j RETURN
-A log-smtp -j REJECT --reject-with icmp-admin-prohibited
COMMIT
