iptables -A OUTPUT -o $EXTERNAL_INTERFACE -p TCP \ --sport $UNPRIVPORTS --dport 465 -s $EXTERNAL_IP -d $SMTP_SRVR -j ACCEPT iptables -A INPUT -i $EXTERNAL_INTERFACE -p TCP -m state --state ESTABLISHED,RELATED \ --sport 465 --dport $UNPRIVPORTS -s $SMTP_SRVR -d $EXTERNAL_IP -j ACCEPT