contrib/package: freifunk-firewall: introduce per-zone option "local_restrict" to only grant access to the default gateway in this zone while rejecting other hosts in the target subnet

1 files changed, 76 insertions, 0 deletions

diff --git a/contrib/package/freifunk-firewall/files/etc/hotplug.d/firewall/23-restricted-wan b/contrib/package/freifunk-firewall/files/etc/hotplug.d/firewall/23-restricted-wan
new file mode 100644
index 000000000..d0795b629
--- /dev/null
+++ b/contrib/package/freifunk-firewall/files/etc/hotplug.d/firewall/23-restricted-wan
@@ -0,0 +1,76 @@
+#!/bin/sh
+
+clear_restricted_gw()
+{
+	local state="$1"
+	local iface
+	local ifname
+	local ipaddr
+	local netmask
+	local gateway
+
+	config_get iface "$state" iface
+
+	if [ "$iface" = "$INTERFACE" ]; then
+		config_get ifname "$state" ifname
+		config_get ipaddr "$state" ipaddr
+		config_get netmask "$state" netmask
+		config_get gateway "$state" gateway
+
+		logger -t firewall.freifunk "removing local restriction to $iface($gateway)"
+		iptables -D "zone_${INTERFACE}_ACCEPT" -i ! $ifname -o $ifname -d $ipaddr/$netmask -j REJECT
+		iptables -D "zone_${INTERFACE}_ACCEPT" -i ! $ifname -o $ifname -d $gateway -j ACCEPT
+
+		uci_revert_state firewall "$state"
+	fi
+}
+
+get_enabled()
+{
+	local name
+	config_get name "$1" name
+
+	if [ "$name" = "$ZONE" ]; then
+		config_get_bool local_restrict "$1" local_restrict
+	fi
+}
+
+if [ "$ACTION" = add ]; then
+	local enabled
+	local ipaddr
+	local netmask
+	local gateway
+
+	include /lib/network
+	scan_interfaces
+
+	config_get ipaddr "$INTERFACE" ipaddr
+	config_get netmask "$INTERFACE" netmask
+	config_get gateway "$INTERFACE" gateway
+
+	if [ -n "$gateway" ] && [ "$gateway" != 0.0.0.0 ]; then
+		config_load firewall
+
+		local_restrict=0
+		config_foreach get_enabled zone
+
+		if [ "$local_restrict" = 1 ]; then
+			logger -t firewall.freifunk "restricting local access to $DEVICE($gateway)"
+			iptables -I "zone_${INTERFACE}_ACCEPT" -i ! $DEVICE -o $DEVICE -d $ipaddr/$netmask -j REJECT
+			iptables -I "zone_${INTERFACE}_ACCEPT" -i ! $DEVICE -o $DEVICE -d $gateway -j ACCEPT
+
+			local state="restricted_gw_${INTERFACE}"
+			uci_set_state firewall "$state" "" restricted_gw_state
+			uci_set_state firewall "$state" iface "$INTERFACE"
+			uci_set_state firewall "$state" ifname "$DEVICE"
+			uci_set_state firewall "$state" ipaddr "$ipaddr"
+			uci_set_state firewall "$state" netmask "$netmask"
+			uci_set_state firewall "$state" gateway "$gateway"
+		fi
+	fi
+
+elif [ "$ACTION" = remove ]; then
+	config_load firewall
+	config_foreach clear_restricted_gw restricted_gw_state	 
+fi
+