--- badi/public_scripts/switchgate/dhclient-exit-hooks.d/switchgate-helper	2009/04/23 17:42:48	1.1.1.1
+++ badi/public_scripts/switchgate/dhclient-exit-hooks.d/switchgate-helper	2020/04/04 21:29:07	1.3
@@ -2,16 +2,62 @@
 # dhclient-exit-hook: switchgate-helper
 
 RUN="yes"
-
+SWITCHGATE="/usr/local/sbin/switchgate"
 
 if [ "$RUN" = "yes" ]; then 
 
-	SWITCHGATE_CONFDIR=$(/usr/local/sbin/switchgate -C)
-	
-	if [ ! -d $SWITCHGATE_CONFDIR ]; then
-		mkdir "$SWITCHGATE_CONFDIR"
+	# ipv4 or ipv6?
+	if [ -z "$(echo "$reason" | sed -e "s/^.*6$//")" ]; then
+		IF_FILENAME="dhcp6.${interface}"
+		IPV="IPv6"
+	else
+		IF_FILENAME="dhcp.${interface}"
+		IPV="IPv4"
+	fi
+
+	# get writeable tmp dir from switchgate
+	SWITCHGATE_TMPDIR="$("$SWITCHGATE" -C)"
+	if [ $? -ne 0 ]; then
+		echo -e "Error: Failed to query switchgate:\n\n$SWITCHGATE_TMPDIR"
+		exit 1
+	elif [ -z "$SWITCHGATE_TMPDIR" ]; then
+		echo "Error: No writeable dir from switchgate received. Please check."
+		exit 1
 	fi
 
-	# Register switchgate routers
-	echo "$new_routers" | sed -e "s/ /\n/g" > "$SWITCHGATE_CONFDIR"/dhcp.$interface
+	
+	case "$reason" in 
+
+	    BOUND|RENEW|REBIND|REBOOT|BOUND6|RENEW6|REBIND6|REBOOT6)
+
+		# check there is a gateway given
+		if [ -z "$new_routers" ]; then
+			echo "No $IPV gateway supplied from DHCP server."
+			# remove the gw file
+			if [ -f "$SWITCHGATE_TMPDIR/$IF_FILENAME" ]; then
+				rm "$SWITCHGATE_TMPDIR/$IF_FILENAME"
+			fi
+			exit 0
+		fi
+		
+		# create writeable dir if not already existing
+		if [ ! -d "$SWITCHGATE_TMPDIR" ]; then
+			mkdir "$SWITCHGATE_TMPDIR"
+		fi
+
+		echo "Adding DHCP supplied gateways to the list of gateways for switchgate: $new_routers"
+
+		# Register switchgate routers
+		echo "$new_routers" | sed -e "s/ /\n/g" > "$SWITCHGATE_TMPDIR/$IF_FILENAME"
+		;;
+
+	    *)
+		# remove the gw file
+		if [ -f "$SWITCHGATE_TMPDIR/$IF_FILENAME" ]; then
+			rm "$SWITCHGATE_TMPDIR/$IF_FILENAME"
+		fi
+		exit 0
+		;;
+
+	esac
 fi