mwan3: add troublshoot command from LuCI

Signed-off-by: Florian Eckert <fe@dev.tdt.de>

net/mwan3/files/usr/sbin/mwan3

@@ -30,6 +30,7 @@ EOF
 	command_help "connected" "Show directly connected networks"
 	command_help "rules" "Show active rules"
 	command_help "status" "Show all status"
+	command_help "internal <ipv4|ipv6>" "Show internal configuration <default: ipv4>"
 	command_help "use <iface> <cmd>" "Run a command bound to <iface> and avoid mwan3 rules"
 }
 
@@ -113,6 +114,92 @@ status()
 	rules
 }
 
+internal()
+{
+	local family="$1"
+	local dash="-------------------------------------------------"
+
+	if [ -f "/etc/openwrt_release" ]; then
+		. /etc/openwrt_release
+	fi
+
+	local ipt ip output
+
+	if [ "$family" = "ipv6" ]; then
+		ipt="$IPT6"
+		ip="$IP6"
+	else
+		ipt="$IPT4"
+		ip="$IP4"
+	fi
+
+	echo "Software-Version"
+	echo "$dash"
+
+	if [ "$DISTRIB_RELEASE" != "" ]; then
+		echo "OpenWrt - $DISTRIB_RELEASE"
+	else
+		echo "OpenWrt - unknown"
+	fi
+
+	echo ""
+	echo "Output of \"$ip a show\""
+	echo "$dash"
+	output="$($ip a show)"
+	if [ "$output" != "" ]; then
+		echo "$output"
+	else
+		echo "No data found"
+	fi
+
+	echo ""
+	echo "Output of \"$ip route show\""
+	echo "$dash"
+	output="$($ip route show)"
+	if [ "$output" != "" ]; then
+		echo "$output"
+	else
+		echo "No data found"
+	fi
+
+	echo ""
+	echo "Output of \"$ip rule show\""
+	echo "$dash"
+	output="$($ip rule show)"
+	if [ "$output" != "" ]; then
+		echo "$output"
+	else
+		echo "No data found"
+	fi
+
+	echo ""
+	echo "Output of \"$ip route list table 1-250\""
+	echo "$dash"
+	local dump=0
+	for i in $(seq 1 250); do
+		output=$($ip route list table $i 2>/dev/null)
+		if [ "$output" != "" ];then
+			dump=1
+			echo "Routing table $i:"
+			echo "$output"
+			echo ""
+		fi
+	done
+	if [ "$dump" = "0" ]; then
+		echo "No data found"
+		echo ""
+	fi
+
+	echo "Output of \"$ipt -L -v -n\""
+	echo "$dash"
+	output="$($ipt -L -v -n)"
+	if [ "$output" != "" ]; then
+		echo "$output"
+	else
+		echo "No data found"
+	fi
+}
+
 start() {
 	/etc/init.d/mwan3 enable
 	/etc/init.d/mwan3 start
@@ -154,7 +241,7 @@ use() {
 }
 
 case "$1" in
-	ifup|ifdown|interfaces|policies|connected|rules|status|start|stop|restart|use)
+	ifup|ifdown|interfaces|policies|connected|rules|status|start|stop|restart|use|internal)
 		mwan3_init
 		# shellcheck disable=SC2048
 		$*