1 #!/bin/sh /etc/rc.common
2 # Copyright (C) 2006 OpenWrt.org
4 ## Please make changes in /etc/firewall.user
10 config_get WAN wan ifname
11 config_get WANDEV wan device
12 config_get LAN lan ifname
15 for T in filter nat; do
20 iptables -N input_rule
22 iptables -N output_rule
23 iptables -N forwarding_rule
24 iptables -N forwarding_wan
26 iptables -t nat -N prerouting_rule
27 iptables -t nat -N prerouting_wan
28 iptables -t nat -N postrouting_rule
30 iptables -N LAN_ACCEPT
31 [ -z "$WAN" ] || iptables -A LAN_ACCEPT -i "$WAN" -j RETURN
32 [ -z "$WANDEV" -o "$WANDEV" = "$WAN" ] || iptables -A LAN_ACCEPT -i "$WANDEV" -j RETURN
33 iptables -A LAN_ACCEPT -j ACCEPT
36 ### (connections with the router as destination)
39 iptables -P INPUT DROP
40 iptables -A INPUT -m state --state INVALID -j DROP
41 iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
42 iptables -A INPUT -p tcp --tcp-flags SYN SYN --tcp-option \! 2 -j DROP
45 # insert accept rule or to jump to new accept-check table here
47 iptables -A INPUT -j input_rule
48 [ -z "$WAN" ] || iptables -A INPUT -i $WAN -j input_wan
51 iptables -A INPUT -j LAN_ACCEPT # allow from lan/wifi interfaces
52 iptables -A INPUT -p icmp -j ACCEPT # allow ICMP
53 iptables -A INPUT -p gre -j ACCEPT # allow GRE
55 # reject (what to do with anything not allowed earlier)
56 iptables -A INPUT -p tcp -j REJECT --reject-with tcp-reset
57 iptables -A INPUT -j REJECT --reject-with icmp-port-unreachable
60 ### (connections with the router as source)
63 iptables -P OUTPUT DROP
64 iptables -A OUTPUT -m state --state INVALID -j DROP
65 iptables -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
68 # insert accept rule or to jump to new accept-check table here
70 iptables -A OUTPUT -j output_rule
73 iptables -A OUTPUT -j ACCEPT #allow everything out
75 # reject (what to do with anything not allowed earlier)
76 iptables -A OUTPUT -p tcp -j REJECT --reject-with tcp-reset
77 iptables -A OUTPUT -j REJECT --reject-with icmp-port-unreachable
80 ### (connections routed through the router)
83 iptables -P FORWARD DROP
84 iptables -A FORWARD -m state --state INVALID -j DROP
85 iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
86 iptables -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
89 # insert accept rule or to jump to new accept-check table here
91 iptables -A FORWARD -j forwarding_rule
92 [ -z "$WAN" ] || iptables -A FORWARD -i $WAN -j forwarding_wan
95 iptables -A FORWARD -i $LAN -o $LAN -j ACCEPT
96 [ -z "$WAN" ] || iptables -A FORWARD -i $LAN -o $WAN -j ACCEPT
98 # reject (what to do with anything not allowed earlier)
99 # uses the default -P DROP
102 iptables -t nat -A PREROUTING -j prerouting_rule
103 [ -z "$WAN" ] || iptables -t nat -A PREROUTING -i "$WAN" -j prerouting_wan
104 iptables -t nat -A POSTROUTING -j postrouting_rule
105 [ -z "$WAN" ] || iptables -t nat -A POSTROUTING -o $WAN -j MASQUERADE
108 [ -f /etc/firewall.user ] && . /etc/firewall.user
109 [ -n "$WAN" -a -e /etc/config/firewall ] && {
111 awk -f /usr/lib/common.awk -f /usr/lib/firewall.awk /etc/config/firewall | ash
116 iptables -P INPUT ACCEPT
117 iptables -P OUTPUT ACCEPT
118 iptables -P FORWARD ACCEPT
121 iptables -t nat -P PREROUTING ACCEPT
122 iptables -t nat -P POSTROUTING ACCEPT
123 iptables -t nat -P OUTPUT ACCEPT