add firewall script change from whiterussian to head

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@1305 3c298f89-4303-0410-b956-a3cf2f4a3e73

openwrt/target/default/target_skeleton/etc/firewall.user

@@ -0,0 +1,27 @@
+#!/bin/sh
+. /etc/functions.sh
+
+WAN=$(nvram get wan_ifname)
+LAN=$(nvram get lan_ifname)
+
+iptables -F input_rule
+iptables -F output_rule
+iptables -F forwarding_rule
+iptables -F prerouting_rule
+iptables -F postrouting_rule
+
+### BIG FAT DISCLAIMER
+### The "-i $WAN" literally means packets that came in over the $WAN interface;
+### this WILL NOT MATCH packets sent from the LAN to the WAN address.
+
+### Allow SSH from WAN
+# iptables -t nat -A prerouting_rule -i $WAN -p tcp --dport 22 -j ACCEPT 
+# iptables        -A input_rule      -i $WAN -p tcp --dport 22 -j ACCEPT
+
+### Port forwarding
+# iptables -t nat -A prerouting_rule -i $WAN -p tcp --dport 22 -j DNAT --to 192.168.1.2
+# iptables        -A forwarding_rule -i $WAN -p tcp --dport 22 -d 192.168.1.2 -j ACCEPT
+
+### DMZ (should be placed after port forwarding / accept rules)
+# iptables -t nat -A prerouting_rule -i $WAN -j DNAT --to 192.168.1.2
+# iptables        -A forwarding_rule -i $WAN -d 192.168.1.2 -j ACCEPT

openwrt/target/default/target_skeleton/etc/init.d/S45firewall

@@ -1,4 +1,7 @@
 #!/bin/sh
+
+## Please make changes in /etc/firewall.user
+
 . /etc/functions.sh
 WAN=$(nvram get wan_ifname)
 LAN=$(nvram get lan_ifname)
@@ -25,15 +28,16 @@ iptables -t nat -N postrouting_rule
   iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
   iptables -A INPUT -p tcp --syn --tcp-option \! 2 -j  DROP
 
-  # allow
-  iptables -A INPUT -i \! $WAN	-j ACCEPT	# allow from lan/wifi interfaces 
-  iptables -A INPUT -p icmp	-j ACCEPT	# allow ICMP
-  iptables -A INPUT -p gre	-j ACCEPT	# allow GRE
   #
   # insert accept rule or to jump to new accept-check table here
   #
   iptables -A INPUT -j input_rule
 
+  # allow
+  iptables -A INPUT -i \! $WAN	-j ACCEPT	# allow from lan/wifi interfaces 
+  iptables -A INPUT -p icmp	-j ACCEPT	# allow ICMP
+  iptables -A INPUT -p gre	-j ACCEPT	# allow GRE
+
   # reject (what to do with anything not allowed earlier)
   iptables -A INPUT -p tcp -j REJECT --reject-with tcp-reset
   iptables -A INPUT -j REJECT --reject-with icmp-port-unreachable
@@ -46,13 +50,14 @@ iptables -t nat -N postrouting_rule
   iptables -A OUTPUT -m state --state INVALID -j DROP
   iptables -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
 
-  # allow
-  iptables -A OUTPUT -j ACCEPT		#allow everything out
   #
   # insert accept rule or to jump to new accept-check table here
   #
   iptables -A OUTPUT -j output_rule
 
+  # allow
+  iptables -A OUTPUT -j ACCEPT		#allow everything out
+
   # reject (what to do with anything not allowed earlier)
   iptables -A OUTPUT -p tcp -j REJECT --reject-with tcp-reset
   iptables -A OUTPUT -j REJECT --reject-with icmp-port-unreachable
@@ -66,14 +71,15 @@ iptables -t nat -N postrouting_rule
   iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
   iptables -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
 
-  # allow
-  iptables -A FORWARD -i br0 -o br0 -j ACCEPT
-  iptables -A FORWARD -i $LAN -o $WAN -j ACCEPT
   #
   # insert accept rule or to jump to new accept-check table here
   #
   iptables -A FORWARD -j forwarding_rule
 
+  # allow
+  iptables -A FORWARD -i br0 -o br0 -j ACCEPT
+  iptables -A FORWARD -i $LAN -o $WAN -j ACCEPT
+
   # reject (what to do with anything not allowed earlier)
   # uses the default -P DROP
 
@@ -83,4 +89,4 @@ iptables -t nat -N postrouting_rule
   iptables -t nat -A POSTROUTING -o $WAN -j MASQUERADE
 
 ## USER RULES
-. /etc/firewall.user
+[ -f /etc/firewall.user ] && . /etc/firewall.user