Properly uses default-route in annotation to set the gateway. Fixes network status results.

k8sclient/k8sclient.go

@@ -112,6 +112,20 @@ func SetNetworkStatus(client KubeClient, k8sArgs *types.K8sArgs, netStatus []*ty
 	if netStatus != nil {
 		var networkStatus []string
 		for _, status := range netStatus {
+			// Clean each empty gateway
+			// Otherwise we wind up with JSON that's a "default-route": [""]
+			cleargateway := true
+			for _, eachgateway := range status.Gateway {
+				if eachgateway != nil {
+					cleargateway = false
+				}
+			}
+
+			if cleargateway {
+				status.Gateway = nil
+			}
+
+			// Now we can sanely marshal the JSON output
 			data, err := json.MarshalIndent(status, "", "    ")
 			if err != nil {
 				return logging.Errorf("SetNetworkStatus: error with Marshal Indent: %v", err)

multus/multus.go

@@ -251,7 +251,7 @@ func delegateAdd(exec invoke.Exec, ifName string, delegate *types.DelegateNetCon
 
 			cniArgs = fmt.Sprintf("%s;MAC=%s", cniArgs, delegate.MacRequest)
 			logging.Debugf("delegateAdd: set MAC address %q to %q", delegate.MacRequest, ifName)
-			rt.Args = append(rt.Args, [2]string{ "MAC", delegate.MacRequest })
+			rt.Args = append(rt.Args, [2]string{"MAC", delegate.MacRequest})
 		}
 
 		if delegate.IPRequest != nil {
@@ -270,7 +270,7 @@ func delegateAdd(exec invoke.Exec, ifName string, delegate *types.DelegateNetCon
 			ips := strings.Join(delegate.IPRequest, ",")
 			cniArgs = fmt.Sprintf("%s;IP=%s", cniArgs, ips)
 			logging.Debugf("delegateAdd: set IP address %q to %q", ips, ifName)
-			rt.Args = append(rt.Args, [2]string{ "IP", ips })
+			rt.Args = append(rt.Args, [2]string{"IP", ips})
 		}
 	}
 
@@ -421,13 +421,35 @@ func cmdAdd(args *skel.CmdArgs, exec invoke.Exec, kubeClient k8s.KubeClient) (cn
 		}
 
 		// Remove gateway from routing table if the gateway is not used
+		deletegateway := false
+		adddefaultgateway := false
 		if delegate.IsFilterGateway {
+			deletegateway = true
+			logging.Debugf("Marked interface %v for gateway deletion", ifName)
+		} else {
+			// Otherwise, determine if this interface now gets our default route.
+			if delegate.GatewayRequest != nil {
+				deletegateway = true
+				adddefaultgateway = true
+				logging.Debugf("Detected gateway override on interface %v to %v", ifName, delegate.GatewayRequest)
+			}
+		}
+
+		if deletegateway {
 			tmpResult, err = netutils.DeleteDefaultGW(args, ifName, &tmpResult)
 			if err != nil {
 				return nil, logging.Errorf("Multus: Err in deleting gateway: %v", err)
 			}
 		}
 
+		// Here we'll set the default gateway
+		if adddefaultgateway {
+			tmpResult, err = netutils.SetDefaultGW(args, ifName, delegate.GatewayRequest, &tmpResult)
+			if err != nil {
+				return nil, logging.Errorf("Multus: Err in setting default gateway: %v", err)
+			}
+		}
+
 		// Master plugin result is always used if present
 		if delegate.MasterPlugin || result == nil {
 			result = tmpResult

netutils/netutils.go

@@ -20,23 +20,21 @@ import (
 	cnitypes "github.com/containernetworking/cni/pkg/types"
 	"github.com/containernetworking/cni/pkg/types/current"
 	"github.com/containernetworking/plugins/pkg/ns"
-
 	"github.com/intel/multus-cni/logging"
-
 	"github.com/vishvananda/netlink"
+	"net"
 )
 
 // DeleteDefaultGW removes the default gateway from marked interfaces.
 func DeleteDefaultGW(args *skel.CmdArgs, ifName string, res *cnitypes.Result) (*current.Result, error) {
-	logging.Debugf("XXX: DeleteDefaultGW: %s", args.Netns)
 	result, err := current.NewResultFromResult(*res)
 	if err != nil {
-		return nil, logging.Errorf("XXX: %v", err)
+		return nil, logging.Errorf("DeleteDefaultGW: Error creating new from current CNI result: %v", err)
 	}
 
 	netns, err := ns.GetNS(args.Netns)
 	if err != nil {
-		return nil, logging.Errorf("XXX: %v", err)
+		return nil, logging.Errorf("DeleteDefaultGW: Error getting namespace %v", err)
 	}
 	defer netns.Close()
 
@@ -60,3 +58,61 @@ func DeleteDefaultGW(args *skel.CmdArgs, ifName string, res *cnitypes.Result) (*
 	result.Routes = newRoutes
 	return result, err
 }
+
+// SetDefaultGW adds a default gateway on a specific interface
+func SetDefaultGW(args *skel.CmdArgs, ifName string, gateways []net.IP, res *cnitypes.Result) (*current.Result, error) {
+
+	// Use the current CNI result...
+	result, err := current.NewResultFromResult(*res)
+	if err != nil {
+		return nil, logging.Errorf("SetDefaultGW: Error creating new CNI result from current: %v", err)
+	}
+
+	// This ensures we're acting within the net namespace for the pod.
+	netns, err := ns.GetNS(args.Netns)
+	if err != nil {
+		return nil, logging.Errorf("SetDefaultGW: Error getting namespace %v", err)
+	}
+	defer netns.Close()
+
+	var newResultDefaultRoutes []*cnitypes.Route
+
+	// Do this within the net namespace.
+	err = netns.Do(func(_ ns.NetNS) error {
+		var err error
+
+		// Pick up the link info as we need the index.
+		link, _ := netlink.LinkByName(ifName)
+
+		// Cycle through all the desired gateways.
+		for _, gw := range gateways {
+
+			// Create a new route (note: dst is nil by default)
+			logging.Debugf("SetDefaultGW: Adding default route on %v (index: %v) to %v", ifName, link.Attrs().Index, gw)
+			newDefaultRoute := netlink.Route{
+				LinkIndex: link.Attrs().Index,
+				Gw:        gw,
+			}
+
+			// Build a new element for the results route
+
+			// Set a correct CIDR depending on IP type
+			_, dstipnet, _ := net.ParseCIDR("::0/0")
+			if gw.To4 != nil {
+				_, dstipnet, _ = net.ParseCIDR("0.0.0.0/0")
+			}
+			newResultDefaultRoutes = append(newResultDefaultRoutes, &cnitypes.Route{Dst: *dstipnet, GW: gw})
+
+			// Perform the creation of the default route....
+			err = netlink.RouteAdd(&newDefaultRoute)
+			if err != nil {
+				logging.Errorf("SetDefaultGW: Error adding route: %v", err)
+			}
+		}
+		return err
+	})
+
+	result.Routes = newResultDefaultRoutes
+	return result, err
+
+}

types/conf.go

@@ -204,7 +204,6 @@ func LoadNetworkStatus(r types.Result, netName string, defaultNet bool) (*Networ
 	logging.Debugf("LoadNetworkStatus: %v, %s, %t", r, netName, defaultNet)
 	netstatus := &NetworkStatus{}
 	netstatus.Name = netName
-	netstatus.Default = defaultNet
 
 	// Convert whatever the IPAM result was into the current Result type
 	result, err := current.NewResultFromResult(r)

types/types.go

@@ -86,7 +86,6 @@ type NetworkStatus struct {
 	Interface string    `json:"interface,omitempty"`
 	IPs       []string  `json:"ips,omitempty"`
 	Mac       string    `json:"mac,omitempty"`
-	Default   bool      `json:"default,omitempty"`
 	DNS       types.DNS `json:"dns,omitempty"`
 	Gateway   []net.IP  `json:"default-route,omitempty"`
 }