1 files changed, 169 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 0000000..129a922
--- /dev/null
+++ b/package/network/config/firewall/files/reflection.hotplug
@@ -0,0 +1,169 @@
+#!/bin/sh
+
+. /lib/functions.sh
+. /lib/functions/network.sh
+
+if [ "$ACTION" = "remove" ]; then
+
+	delete_rules_by_comment() {
+		local table="$1"
+		local chain="$2"
+		local comment="$3"
+
+		iptables -t "$table" --line-numbers -nL "$chain" 2>/dev/null | \
+			sed -e '
+				1d;
+				1! {
+					\#^[0-9]\+ .* /\* '"$comment"' \*/.*$# {
+						s/ .*$//;
+						G; h;
+					}
+				};
+				$!d;
+			' | xargs -n1 iptables -t "$table" -D "$chain" 2>/dev/null
+	}
+
+	delete_rules_by_comment nat    nat_reflection_in  "$INTERFACE"
+	delete_rules_by_comment nat    nat_reflection_out "$INTERFACE"
+	delete_rules_by_comment filter nat_reflection_fwd "$INTERFACE"
+
+elif [ "$ACTION" = "add" ]; then
+
+	prepare_chains() {
+		iptables -t nat -N nat_reflection_in 2>/dev/null && {
+			iptables -t nat -A prerouting_rule -j nat_reflection_in
+		}
+
+		iptables -t nat -N nat_reflection_out 2>/dev/null && {
+			iptables -t nat -A postrouting_rule -j nat_reflection_out
+		}
+
+		iptables -t filter -N nat_reflection_fwd 2>/dev/null && {
+			iptables -t filter -A forwarding_rule -j nat_reflection_fwd
+		}
+	}
+
+	find_networks() {
+		find_networks_cb() {
+			local cfg="$1"
+			local zone="$2"
+			local need_masq="${3:-0}"
+
+			local name
+			config_get name "$cfg" name
+
+			local masq
+			config_get_bool masq "$cfg" masq 0
+
+			[ "$name" = "$zone" ] && [ "$masq" -ge "$need_masq" ] && {
+				local network
+				config_get network "$cfg" network
+
+				echo ${network:-$zone}
+				return 1
+			}
+		}
+
+		config_foreach find_networks_cb zone "$@"
+	}
+
+	setup_fwd() {
+		local cfg="$1"
+
+		local reflection
+		config_get_bool reflection "$cfg" reflection 1
+		[ "$reflection" == 1 ] || return
+
+		local src
+		config_get src "$cfg" src
+		[ "$src" == "$ZONE" ] || return
+
+		local dest
+		config_get dest "$cfg" dest
+		[ "$dest" != "*" ] || return
+
+		local target
+		config_get target "$cfg" target DNAT
+		[ "$target" = DNAT ] || return
+
+		prepare_chains
+
+		local net
+		for net in $(find_networks "$dest" 0); do
+			local intnet
+			network_get_subnet intnet "$net" || continue
+
+			local proto
+			config_get proto "$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 "$cfg" src_dip "$extip"
+
+			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 $intnet -d $exthost \
+							-p $p $extport \
+							-m comment --comment "$INTERFACE" \
+							-j DNAT --to $inthost:${ipmin#!}${ipmax:+-$ipmax}
+
+						iptables -t nat -A nat_reflection_out \
+							-s $intnet -d $inthost \
+							-p $p $intport \
+							-m comment --comment "$INTERFACE" \
+							-j SNAT --to-source ${intnet%%/*}
+
+						iptables -t filter -A nat_reflection_fwd \
+							-s $intnet -d $inthost \
+							-p $p $intport \
+							-m comment --comment "$INTERFACE" \
+							-j ACCEPT
+					;;
+				esac
+			done
+		done
+	}
+
+	config_load firewall
+
+	local is_masq_zone="$(find_networks "$ZONE" 1)"
+	[ -n "$is_masq_zone" ] || exit 0
+
+	local extip
+	network_get_ipaddr extip "$INTERFACE" || exit 0
+
+	config_foreach setup_fwd redirect
+fi