CNS should send default routes to CNI windows

Author: paulyufan2

cni/network/invoker_cns.go

@@ -487,16 +487,7 @@ func configureSecondaryAddResult(info *IPResultInfo, addResult *IPAMAddResult, p
 	if err != nil {
 		return err
 	}
-
-	resRoute := addResult.interfaceInfo[key].Routes
-	if len(routes) > 0 {
-		resRoute = append(resRoute, routes...)
-	} else { // add default route to customer vnet on swiftv2 windows
-		resRoute = append(resRoute, network.RouteInfo{
-			Dst: network.Ipv4DefaultRouteDstPrefix,
-			Gw:  net.ParseIP(info.ncGatewayIPAddress),
-		})
-	}
+	logger.Info("routes are now", zap.Any("routes are now", routes))
 
 	addResult.interfaceInfo[key] = network.InterfaceInfo{
 		IPConfigs: []*network.IPConfig{
@@ -508,7 +499,7 @@ func configureSecondaryAddResult(info *IPResultInfo, addResult *IPAMAddResult, p
 				Gateway: net.ParseIP(info.ncGatewayIPAddress),
 			},
 		},
-		Routes:            resRoute,
+		Routes:            routes,
 		NICType:           info.nicType,
 		MacAddress:        macAddress,
 		SkipDefaultRoutes: info.skipDefaultRoutes,

cni/network/network.go

@@ -856,7 +856,7 @@ func (plugin *NetPlugin) createEpInfo(opt *createEpInfoOpt) (*network.EndpointIn
 	}
 
 	setEndpointOptions(opt.cnsNetworkConfig, &endpointInfo, vethName)
-
+	logger.Info("endpointInfo routes are", zap.Any("endpointInfo routes", endpointInfo.Routes))
 	logger.Info("Generated endpoint info from fields", zap.String("epInfo", endpointInfo.PrettyString()))
 
 	// now our ep info should have the full combined information from both the network and endpoint structs

cns/middlewares/k8sSwiftV2_windows.go

@@ -1,6 +1,8 @@
 package middlewares
 
 import (
+	"fmt"
+
 	"github.com/Azure/azure-container-networking/cns"
 	"github.com/Azure/azure-container-networking/cns/logger"
 	"github.com/Azure/azure-container-networking/cns/middlewares/utils"
@@ -15,6 +17,7 @@ func (k *K8sSWIFTv2Middleware) setRoutes(podIPInfo *cns.PodIpInfo) error {
 		logger.Printf("[SWIFTv2Middleware] skip setting default route on InfraNIC interface")
 		podIPInfo.SkipDefaultRoutes = true
 	}
+
 	return nil
 }
 
@@ -40,5 +43,15 @@ func (k *K8sSWIFTv2Middleware) assignSubnetPrefixLengthFields(podIPInfo *cns.Pod
 		},
 		GatewayIPAddress: interfaceInfo.GatewayIP,
 	}
+	// assign routes
+	virtualGWRoute := cns.Route{
+		IPAddress: fmt.Sprintf("%s/%d", interfaceInfo.GatewayIP, prefixLength),
+	}
+	route := cns.Route{
+		IPAddress:        "0.0.0.0/0",
+		GatewayIPAddress: virtualGW,
+	}
+	podIPInfo.Routes = append(podIPInfo.Routes, virtualGWRoute, route)
+
 	return nil
 }

network/transparent_endpointclient_linux.go

@@ -233,7 +233,7 @@ func (client *TransparentEndpointClient) ConfigureContainerInterfacesAndRoutes(e
 
 	// add route for virtualgwip
 	// ip route add 169.254.1.1/32 dev eth0
-	_, virtualGwNet, _ := net.ParseCIDR(virtualGwIPString)
+	virtualGwIP, virtualGwNet, _ := net.ParseCIDR(virtualGwIPString)
 	routeInfo := RouteInfo{
 		Dst:   *virtualGwNet,
 		Scope: netlink.RT_SCOPE_LINK,
@@ -242,7 +242,18 @@ func (client *TransparentEndpointClient) ConfigureContainerInterfacesAndRoutes(e
 		return newErrorTransparentEndpointClient(err)
 	}
 
-	if err := addRoutes(client.netlink, client.netioshim, client.containerVethName, epInfo.Routes); err != nil {
+	if !epInfo.SkipDefaultRoutes {
+		// ip route add default via 169.254.1.1 dev eth0
+		_, defaultIPNet, _ := net.ParseCIDR(defaultGwCidr)
+		dstIP := net.IPNet{IP: net.ParseIP(defaultGw), Mask: defaultIPNet.Mask}
+		routeInfo = RouteInfo{
+			Dst: dstIP,
+			Gw:  virtualGwIP,
+		}
+		if err := addRoutes(client.netlink, client.netioshim, client.containerVethName, []RouteInfo{routeInfo}); err != nil {
+			return err
+		}
+	} else if err := addRoutes(client.netlink, client.netioshim, client.containerVethName, epInfo.Routes); err != nil {
 		return newErrorTransparentEndpointClient(err)
 	}