wg-installer: add babeld hotplug.d script

Add a hotplug.d-extension that automatically configures babeld for
meshing via wireguard interfaces.

It checks for "add" and "remove" of a wireguard interface with name
"wg_*". Depending on the action, it removes it from the babeld config
or adds the interface and reloads babeld.

Signed-off-by: Nick Hainke <vincent@systemli.org>

net/wg-installer/wg-server/hotplug.d/99-mesh-babeld

@@ -0,0 +1,31 @@
+#!/bin/sh
+
+# check if wireguard
+if [ "${DEVTYPE}" != "wireguard" ]; then
+	exit 0
+fi
+
+# check if correct naming
+slicedint=$(echo $INTERFACE | cut -c1-3)
+if [ "${slicedint}" != "wg_" ]; then
+	exit 0
+fi
+
+if [ "${ACTION}" == "add" ]; then
+	uci add babeld interface
+	uci set babeld.@interface[-1].ifname="${INTERFACE}"
+	uci commit
+	/etc/init.d/babeld reload
+fi
+
+if [ "${ACTION}" == "remove" ]; then
+	i=0
+	while uci get babeld.@interface[$i] &> /dev/null ; do
+		if [ "$(uci get babeld.@interface[$i].ifname)" == "${INTERFACE}" ]; then
+			uci delete babeld.@interface[$i]
+		fi
+		i=$((i+1));
+	done
+	uci commit
+	/etc/init.d/babeld reload
+fi