Fix Routers destroy with BYO

When using your own Network for the Machines
connected to a tagged Router created by CNO
on an installation with Kuryr, the Subnet of
that Network is not tagged and consequently
not identified by installer when destroying
the Router. This commit fixes the issue by
ensuring all Subnetes connected to a Router
created by Installer or CNO are removed.

pkg/destroy/openstack/openstack.go

@@ -482,7 +482,7 @@ func deleteRouters(opts *clientconfig.ClientOpts, filter Filter, logger logrus.F
 			logger.Error(err)
 		}
 
-		_, err = removeRouterInterfaces(conn, filter, router.ID, logger)
+		_, err = removeRouterInterfaces(conn, filter, router, logger)
 		if err != nil {
 			return false, nil
 		}
@@ -577,17 +577,17 @@ func deleteCustomRouterInterfaces(opts *clientconfig.ClientOpts, filter Filter,
 	}
 
 	// Discover router by interface from the primary Network
-	routerID, err := getRouterByPort(conn, allPrimayNetworkPorts)
+	router, err := getRouterByPort(conn, allPrimayNetworkPorts)
 	if err != nil {
 		logger.Debug(err)
 		return false, nil
 	}
-	if routerID == "" {
+	if router.ID == "" {
 		return true, nil
 	}
 
 	fipOpts := floatingips.ListOpts{
-		RouterID: routerID,
+		RouterID: router.ID,
 		Tags:     strings.Join(tags, ","),
 	}
 
@@ -610,18 +610,18 @@ func deleteCustomRouterInterfaces(opts *clientconfig.ClientOpts, filter Filter,
 		return false, nil
 	}
 
-	removed, err := removeRouterInterfaces(conn, filter, routerID, logger)
+	removed, err := removeRouterInterfaces(conn, filter, router, logger)
 	if err != nil {
 		logger.Debug(err)
 		return false, nil
 	}
 	return removed, nil
 }
 
-func removeRouterInterfaces(client *gophercloud.ServiceClient, filter Filter, routerID string, logger logrus.FieldLogger) (bool, error) {
+func removeRouterInterfaces(client *gophercloud.ServiceClient, filter Filter, router routers.Router, logger logrus.FieldLogger) (bool, error) {
 	// Get router interface ports
 	portListOpts := ports.ListOpts{
-		DeviceID: routerID,
+		DeviceID: router.ID,
 	}
 	allPagesPort, err := ports.List(client, portListOpts).AllPages()
 	if err != nil {
@@ -650,30 +650,35 @@ func removeRouterInterfaces(client *gophercloud.ServiceClient, filter Filter, ro
 		return false, errors.Wrap(err, "failed to extract subnets list")
 	}
 
+	clusterTag := "openshiftClusterID=" + filter["openshiftClusterID"]
+	clusterRouter := isClusterRouter(clusterTag, router.Tags)
+
 	var customInterfaces []ports.Port
 	// map to keep track of whethere interface for subnet was already removed
 	removedSubnets := make(map[string]bool)
 	for _, port := range allPorts {
 		for _, IP := range port.FixedIPs {
-			// Skip removal if interface is not handled by the Cluster
-			if !isClusterSubnet(allSubnets, IP.SubnetID) {
+
+			// Skip removal if Router was not created by CNO or installer and
+			// interface is not handled by the Cluster
+			if !clusterRouter && !isClusterSubnet(allSubnets, IP.SubnetID) {
 				customInterfaces = append(customInterfaces, port)
 				continue
 			}
 			if !removedSubnets[IP.SubnetID] {
 				removeOpts := routers.RemoveInterfaceOpts{
 					SubnetID: IP.SubnetID,
 				}
-				logger.Debugf("Removing Subnet %q from Router %q", IP.SubnetID, routerID)
-				_, err := routers.RemoveInterface(client, routerID, removeOpts).Extract()
+				logger.Debugf("Removing Subnet %q from Router %q", IP.SubnetID, router.ID)
+				_, err := routers.RemoveInterface(client, router.ID, removeOpts).Extract()
 				if err != nil {
 					var gerr gophercloud.ErrDefault404
 					if !errors.As(err, &gerr) {
 						// This can fail when subnet is still in use
-						logger.Debugf("Removing Subnet %q from Router %q failed: %v", IP.SubnetID, routerID, err)
+						logger.Debugf("Removing Subnet %q from Router %q failed: %v", IP.SubnetID, router.ID, err)
 						return false, nil
 					}
-					logger.Debugf("Cannot find subnet %q. It's probably already been removed from router %q.", IP.SubnetID, routerID)
+					logger.Debugf("Cannot find subnet %q. It's probably already been removed from router %q.", IP.SubnetID, router.ID)
 				}
 				removedSubnets[IP.SubnetID] = true
 			}
@@ -683,25 +688,35 @@ func removeRouterInterfaces(client *gophercloud.ServiceClient, filter Filter, ro
 	return len(allPorts) == len(customInterfaces), nil
 }
 
-func getRouterByPort(client *gophercloud.ServiceClient, allPorts []ports.Port) (string, error) {
+func isClusterRouter(clusterTag string, tags []string) bool {
+	for _, tag := range tags {
+		if clusterTag == tag {
+			return true
+		}
+	}
+	return false
+}
+
+func getRouterByPort(client *gophercloud.ServiceClient, allPorts []ports.Port) (routers.Router, error) {
+	empty := routers.Router{}
 	for _, port := range allPorts {
 		if port.DeviceID != "" {
 			page, err := routers.List(client, routers.ListOpts{ID: port.DeviceID}).AllPages()
 			if err != nil {
-				return "", errors.Wrap(err, "failed to get router list")
+				return empty, errors.Wrap(err, "failed to get router list")
 			}
 
 			routerList, err := routers.ExtractRouters(page)
 			if err != nil {
-				return "", errors.Wrap(err, "failed to extract routers list")
+				return empty, errors.Wrap(err, "failed to extract routers list")
 			}
 
 			if len(routerList) == 1 {
-				return routerList[0].ID, nil
+				return routerList[0], nil
 			}
 		}
 	}
-	return "", nil
+	return empty, nil
 }
 
 func deleteLeftoverLoadBalancers(opts *clientconfig.ClientOpts, logger logrus.FieldLogger, networkID string) {