1 files changed, 132 insertions, 0 deletions
diff --git a/package/network/config/firewall/files/reflection.hotplug b/package/network/config/firewall/files/reflection.hotplug
new file mode 100644
index 000000000..843c615bc
--- /dev/null
+++ b/package/network/config/firewall/files/reflection.hotplug
@@ -0,0 +1,132 @@
+#!/bin/sh
+
+. /lib/functions.sh
+. /lib/functions/network.sh
+
+if [ "$ACTION" = "add" ] && [ "$INTERFACE" = "wan" ]; then
+	local wanip
+	network_get_ipaddr wanip wan || return
+
+	iptables -t nat -F nat_reflection_in 2>/dev/null || {
+		iptables -t nat -N nat_reflection_in
+		iptables -t nat -A prerouting_rule -j nat_reflection_in
+	}
+
+	iptables -t nat -F nat_reflection_out 2>/dev/null || {
+		iptables -t nat -N nat_reflection_out
+		iptables -t nat -A postrouting_rule -j nat_reflection_out
+	}
+
+	iptables -t filter -F nat_reflection_fwd 2>/dev/null || {
+		iptables -t filter -N nat_reflection_fwd
+		iptables -t filter -A forwarding_rule -j nat_reflection_fwd
+	}
+
+	find_networks() {
+		find_networks_cb() {
+			local cfg="$1"
+			local zone="$2"
+
+			local name
+			config_get name "$cfg" name
+
+			[ "$name" = "$zone" ] && {
+				local network
+				config_get network "$cfg" network
+
+				echo ${network:-$zone}
+				return 1
+			}
+		}
+
+		config_foreach find_networks_cb zone "$1"
+	}
+
+	setup_fwd() {
+		local cfg="$1"
+
+		local reflection
+		config_get_bool reflection "$cfg" reflection 1
+		[ "$reflection" == 1 ] || return
+
+		local src
+		config_get src "$cfg" src
+
+		local target
+		config_get target "$cfg" target DNAT
+
+		[ "$src" = wan ] && [ "$target" = DNAT ] && {
+			local dest
+			config_get dest "$cfg" dest "lan"
+			[ "$dest" != "*" ] || return
+
+			local net
+			for net in $(find_networks "$dest"); do
+				local lannet
+				network_get_subnet lannet "$net" || return
+
+				local proto
+				config_get proto "$cfg" proto
+
+				local epmin epmax extport
+				config_get extport "$cfg" src_dport "1-65535"
+				[ -n "$extport" ] || return
+
+				epmin="${extport%[-:]*}"; epmax="${extport#*[-:]}"
+				[ "${epmin#!}" != "$epmax" ] || epmax=""
+
+				local ipmin ipmax intport
+				config_get intport "$cfg" dest_port "$extport"
+
+				ipmin="${intport%[-:]*}"; ipmax="${intport#*[-:]}"
+				[ "${ipmin#!}" != "$ipmax" ] || ipmax=""
+
+				local exthost
+				config_get exthost "$cfg" src_dip "$wanip"
+
+				local inthost
+				config_get inthost "$cfg" dest_ip
+				[ -n "$inthost" ] || return
+
+				[ "$proto" = all    ] && proto="tcp udp"
+				[ "$proto" = tcpudp ] && proto="tcp udp"
+
+				[ "${inthost#!}" = "$inthost" ] || return 0
+				[ "${exthost#!}" = "$exthost" ] || return 0
+
+				[ "${epmin#!}" != "$epmin" ] && \
+					extport="! --dport ${epmin#!}${epmax:+:$epmax}" || \
+					extport="--dport $epmin${epmax:+:$epmax}"
+
+				[ "${ipmin#!}" != "$ipmin" ] && \
+					intport="! --dport ${ipmin#!}${ipmax:+:$ipmax}" || \
+					intport="--dport $ipmin${ipmax:+:$ipmax}"
+
+				local p
+				for p in ${proto:-tcp udp}; do
+					case "$p" in
+						tcp|udp|6|17)
+							iptables -t nat -A nat_reflection_in \
+								-s $lannet -d $exthost \
+								-p $p $extport \
+								-j DNAT --to $inthost:${ipmin#!}${ipmax:+-$ipmax}
+
+							iptables -t nat -A nat_reflection_out \
+								-s $lannet -d $inthost \
+								-p $p $intport \
+								-j SNAT --to-source ${lannet%%/*}
+
+							iptables -t filter -A nat_reflection_fwd \
+								-s $lannet -d $inthost \
+								-p $p $intport \
+								-j ACCEPT
+						;;
+					esac
+				done
+			done
+		}
+	}
+
+	config_load firewall
+	config_foreach setup_fwd redirect
+fi