Iptables-script

#!/bin/sh
wanip=`wget -qO- http://checkip.dyndns.org/ | sed 's|.* \([[:digit:]]*\.[[:digit:]]*\.[[:digit:]]*\.[[:digit:]]*\).*|\1|'`
lanip=`ifconfig  | grep 'inet addr:'| grep -v '127.0.0.1' | cut -d: -f2 | awk '{ print $1}'`
echo "Rewriting iptables using $wanip(wan) and $lanip(lan)..."
iptables -t nat -A OUTPUT --dst $wanip -p tcp --dport 9000:9010 -j DNAT --to-destination $lanip
iptables -t nat -A OUTPUT --dst $wanip -p udp --dport 9000:9010 -j DNAT --to-destination $lanip