# Creates a routing rule to external interface
if [ -z ${1:-}]
then
    external_if=eth0
else
    external_if=$1
fi
$do_action -t nat $IPTABLES_ADD $IT_INPUT -A $IT_POSTROUTING -s '10.1.0.0/24' -o $external_if -j MASQUERADE
$do_action -t raw $IPTABLES_INSERT $IT_INPUT -I $IT_PREROUTING -i fwbr+ -j CT --zone 1
$do_action -t nat $IPTABLES_INSERT $IT_INPUT -D $IT_POSTROUTING -s '10.1.0.0/24' -o $external_if -j MASQUERADE
$do_action -t raw $IPTABLES_INSERT $IT_INPUT -D $IT_PREROUTING -i fwbr+ -j CT --zone 1