4 export WAN=$(nvram get wan_ifname)
5 export IPT=/usr/sbin/iptables
7 for T in filter nat mangle ; do
13 $IPT -t filter -A INPUT -m state --state INVALID -j DROP
14 $IPT -t filter -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
15 $IPT -t filter -A FORWARD -m state --state INVALID -j DROP
16 $IPT -t filter -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
18 if [ -d /etc/firewall.d ]; then
19 for fw in /etc/firewall.d/??*; do
26 $IPT -t filter -A INPUT -p icmp -j ACCEPT
27 $IPT -t filter -A INPUT -p 47 -j ACCEPT
28 $IPT -t filter -A INPUT -i $WAN -p tcp -j REJECT --reject-with tcp-reset
29 $IPT -t filter -A INPUT -i $WAN -j REJECT --reject-with icmp-port-unreachable
31 $IPT -t filter -A FORWARD -i $WAN -m state --state NEW,INVALID -j DROP
32 $IPT -t filter -A FORWARD -o $WAN -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
34 $IPT -t nat -A POSTROUTING -o $WAN -j MASQUERADE