iptables.sh

gistfile1.txt

IPT=$(which iptables)
#IPT=echo
LAN=("eth1" "eth2" "wlan0")
WAN="eth0"

$IPT -F
$IPT -t nat -F

$IPT -P INPUT ACCEPT
$IPT -P OUTPUT ACCEPT
$IPT -P FORWARD DROP

$IPT -I INPUT 1 -i lo      -j ACCEPT
for IF in ${LAN[@]}
do
  $IPT -I INPUT 1 -i ${IF} -j ACCEPT
  $IPT -A INPUT -p UDP --dport bootps ! -i ${IF} -j REJECT
  $IPT -A INPUT -p UDP --dport domain ! -i ${IF} -j REJECT

  $IPT -I FORWARD -i ${IF} -d 10.13.37.0/255.255.255.0 -j DROP
  $IPT -A FORWARD -i ${IF} -s 10.13.37.0/255.255.255.0 -j ACCEPT
done

$IPT -A FORWARD -i ${WAN}  -d 10.13.37.0/255.255.255.0 -j ACCEPT
$IPT -t nat -A POSTROUTING -o ${WAN} -j MASQUERAD