Revert "restrict externalTrafficPolicy=Local interpretation only to NodePort and LoadBalancer services (#819)" (#835)

This reverts commit 27ec314.

Author: murali-reddy

pkg/controllers/proxy/network_services_controller.go

@@ -30,6 +30,7 @@ import (
 	"github.com/vishvananda/netns"
 	"golang.org/x/net/context"
 	api "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/cache"
 )
@@ -834,6 +835,376 @@ func hasActiveEndpoints(svc *serviceInfo, endpoints []endpointsInfo) bool {
 	return false
 }
 
+// sync the ipvs service and server details configured to reflect the desired state of services and endpoint
+// as learned from services and endpoints information from the api server
+func (nsc *NetworkServicesController) syncIpvsServices(serviceInfoMap serviceInfoMap, endpointsInfoMap endpointsInfoMap) error {
+	var ipvsSvcs []*ipvs.Service
+	start := time.Now()
+
+	defer func() {
+		endTime := time.Since(start)
+		if nsc.MetricsEnabled {
+			metrics.ControllerIpvsServicesSyncTime.Observe(endTime.Seconds())
+		}
+		glog.V(1).Infof("sync ipvs services took %v", endTime)
+	}()
+
+	dummyVipInterface, err := nsc.ln.getKubeDummyInterface()
+	if err != nil {
+		return errors.New("Failed creating dummy interface: " + err.Error())
+	}
+
+	glog.V(1).Infof("Setting up policy routing required for Direct Server Return functionality.")
+	err = nsc.ln.setupPolicyRoutingForDSR()
+	if err != nil {
+		return errors.New("Failed setup PBR for DSR due to: " + err.Error())
+	}
+	glog.V(1).Infof("Custom routing table " + customDSRRouteTableName + " required for Direct Server Return is setup as expected.")
+
+	glog.V(1).Infof("Setting up custom route table required to add routes for external IP's.")
+	err = nsc.ln.setupRoutesForExternalIPForDSR(serviceInfoMap)
+	if err != nil {
+		glog.Errorf("Failed setup custom routing table required to add routes for external IP's due to: " + err.Error())
+		return errors.New("Failed setup custom routing table required to add routes for external IP's due to: " + err.Error())
+	}
+	glog.V(1).Infof("Custom routing table " + externalIPRouteTableName + " required for Direct Server Return is setup as expected.")
+
+	// map of active services and service endpoints
+	activeServiceEndpointMap := make(map[string][]string)
+
+	ipvsSvcs, err = nsc.ln.ipvsGetServices()
+	if err != nil {
+		return errors.New("Failed get list of IPVS services due to: " + err.Error())
+	}
+
+	for k, svc := range serviceInfoMap {
+		var protocol uint16
+
+		switch svc.protocol {
+		case "tcp":
+			protocol = syscall.IPPROTO_TCP
+		case "udp":
+			protocol = syscall.IPPROTO_UDP
+		default:
+			protocol = syscall.IPPROTO_NONE
+		}
+
+		endpoints := endpointsInfoMap[k]
+
+		if svc.local && !hasActiveEndpoints(svc, endpoints) {
+			glog.V(1).Infof("Skipping service %s/%s as it does not have active endpoints\n", svc.namespace, svc.name)
+			continue
+		}
+
+		// assign cluster IP of the service to the dummy interface so that its routable from the pod's on the node
+		err := nsc.ln.ipAddrAdd(dummyVipInterface, svc.clusterIP.String(), true)
+		if err != nil {
+			continue
+		}
+
+		// create IPVS service for the service to be exposed through the cluster ip
+		ipvsClusterVipSvc, err := nsc.ln.ipvsAddService(ipvsSvcs, svc.clusterIP, protocol, uint16(svc.port), svc.sessionAffinity, svc.scheduler, svc.flags)
+		if err != nil {
+			glog.Errorf("Failed to create ipvs service for cluster ip: %s", err.Error())
+			continue
+		}
+		var clusterServiceId = generateIpPortId(svc.clusterIP.String(), svc.protocol, strconv.Itoa(svc.port))
+		activeServiceEndpointMap[clusterServiceId] = make([]string, 0)
+
+		// create IPVS service for the service to be exposed through the nodeport
+		var ipvsNodeportSvcs []*ipvs.Service
+
+		var nodeServiceIds []string
+
+		if svc.nodePort != 0 {
+			if nsc.nodeportBindOnAllIp {
+				// bind on all interfaces instead
+				addrs, err := getAllLocalIPs()
+
+				if err != nil {
+					glog.Errorf("Could not get list of system addresses for ipvs services: %s", err.Error())
+					continue
+				}
+
+				if len(addrs) == 0 {
+					glog.Errorf("No IP addresses returned for nodeport service creation!")
+					continue
+				}
+
+				ipvsNodeportSvcs = make([]*ipvs.Service, len(addrs))
+				nodeServiceIds = make([]string, len(addrs))
+
+				for i, addr := range addrs {
+					ipvsNodeportSvcs[i], err = nsc.ln.ipvsAddService(ipvsSvcs, addr.IP, protocol, uint16(svc.nodePort), svc.sessionAffinity, svc.scheduler, svc.flags)
+					if err != nil {
+						glog.Errorf("Failed to create ipvs service for node port due to: %s", err.Error())
+						continue
+					}
+
+					nodeServiceIds[i] = generateIpPortId(addr.IP.String(), svc.protocol, strconv.Itoa(svc.nodePort))
+					activeServiceEndpointMap[nodeServiceIds[i]] = make([]string, 0)
+				}
+			} else {
+				ipvsNodeportSvcs = make([]*ipvs.Service, 1)
+				ipvsNodeportSvcs[0], err = nsc.ln.ipvsAddService(ipvsSvcs, nsc.nodeIP, protocol, uint16(svc.nodePort), svc.sessionAffinity, svc.scheduler, svc.flags)
+				if err != nil {
+					glog.Errorf("Failed to create ipvs service for node port due to: %s", err.Error())
+					continue
+				}
+
+				nodeServiceIds = make([]string, 1)
+				nodeServiceIds[0] = generateIpPortId(nsc.nodeIP.String(), svc.protocol, strconv.Itoa(svc.nodePort))
+				activeServiceEndpointMap[nodeServiceIds[0]] = make([]string, 0)
+			}
+		}
+
+		externalIpServices := make([]externalIPService, 0)
+		// create IPVS service for the service to be exposed through the external IP's
+		// For external IP (which are meant for ingress traffic) Kube-router setsup IPVS services
+		// based on FWMARK to enable Direct server return functionality. DSR requires a director
+		// without a VIP http://www.austintek.com/LVS/LVS-HOWTO/HOWTO/LVS-HOWTO.routing_to_VIP-less_director.html
+		// to avoid martian packets
+		extIPSet := sets.NewString(svc.externalIPs...)
+		if !svc.skipLbIps {
+			extIPSet = extIPSet.Union(sets.NewString(svc.loadBalancerIPs...))
+		}
+
+		for _, externalIP := range extIPSet.List() {
+			var externalIpServiceId string
+			if svc.directServerReturn && svc.directServerReturnMethod == "tunnel" {
+				ipvsExternalIPSvc, err := nsc.ln.ipvsAddFWMarkService(net.ParseIP(externalIP), protocol, uint16(svc.port), svc.sessionAffinity, svc.scheduler, svc.flags)
+				if err != nil {
+					glog.Errorf("Failed to create ipvs service for External IP: %s due to: %s", externalIP, err.Error())
+					continue
+				}
+				externalIpServices = append(externalIpServices, externalIPService{ipvsSvc: ipvsExternalIPSvc, externalIp: externalIP})
+				fwMark := generateFwmark(externalIP, svc.protocol, strconv.Itoa(svc.port))
+				externalIpServiceId = fmt.Sprint(fwMark)
+
+				// ensure there is iptables mangle table rule to FWMARK the packet
+				err = setupMangleTableRule(externalIP, svc.protocol, strconv.Itoa(svc.port), externalIpServiceId)
+				if err != nil {
+					glog.Errorf("Failed to setup mangle table rule to FMWARD the traffic to external IP")
+					continue
+				}
+
+				// ensure VIP less director. we dont assign VIP to any interface
+				err = nsc.ln.ipAddrDel(dummyVipInterface, externalIP)
+
+				// do policy routing to deliver the packet locally so that IPVS can pick the packet
+				err = routeVIPTrafficToDirector("0x" + fmt.Sprintf("%x", fwMark))
+				if err != nil {
+					glog.Errorf("Failed to setup ip rule to lookup traffic to external IP: %s through custom "+
+						"route table due to %s", externalIP, err.Error())
+					continue
+				}
+			} else {
+				// ensure director with vip assigned
+				err := nsc.ln.ipAddrAdd(dummyVipInterface, externalIP, true)
+				if err != nil && err.Error() != IFACE_HAS_ADDR {
+					glog.Errorf("Failed to assign external ip %s to dummy interface %s due to %s", externalIP, KUBE_DUMMY_IF, err.Error())
+				}
+
+				// create IPVS service for the service to be exposed through the external ip
+				ipvsExternalIPSvc, err := nsc.ln.ipvsAddService(ipvsSvcs, net.ParseIP(externalIP), protocol, uint16(svc.port), svc.sessionAffinity, svc.scheduler, svc.flags)
+				if err != nil {
+					glog.Errorf("Failed to create ipvs service for external ip: %s due to %s", externalIP, err.Error())
+					continue
+				}
+				externalIpServices = append(externalIpServices, externalIPService{ipvsSvc: ipvsExternalIPSvc, externalIp: externalIP})
+				externalIpServiceId = generateIpPortId(externalIP, svc.protocol, strconv.Itoa(svc.port))
+
+				// ensure there is NO iptables mangle table rule to FWMARK the packet
+				fwMark := fmt.Sprint(generateFwmark(externalIP, svc.protocol, strconv.Itoa(svc.port)))
+				err = nsc.ln.cleanupMangleTableRule(externalIP, svc.protocol, strconv.Itoa(svc.port), fwMark)
+				if err != nil {
+					glog.Errorf("Failed to verify and cleanup any mangle table rule to FMWARD the traffic to external IP due to " + err.Error())
+					continue
+				}
+			}
+
+			activeServiceEndpointMap[externalIpServiceId] = make([]string, 0)
+			for _, endpoint := range endpoints {
+				if !svc.local || (svc.local && endpoint.isLocal) {
+					activeServiceEndpointMap[externalIpServiceId] = append(activeServiceEndpointMap[externalIpServiceId], endpoint.ip)
+				}
+			}
+		}
+
+		// add IPVS remote server to the IPVS service
+		for _, endpoint := range endpoints {
+			dst := ipvs.Destination{
+				Address:       net.ParseIP(endpoint.ip),
+				AddressFamily: syscall.AF_INET,
+				Port:          uint16(endpoint.port),
+				Weight:        1,
+			}
+
+			if !svc.local || (svc.local && endpoint.isLocal) {
+				err := nsc.ln.ipvsAddServer(ipvsClusterVipSvc, &dst)
+				if err != nil {
+					glog.Errorf(err.Error())
+				} else {
+					activeServiceEndpointMap[clusterServiceId] = append(activeServiceEndpointMap[clusterServiceId], endpoint.ip)
+				}
+			}
+
+			if svc.nodePort != 0 {
+				for i := 0; i < len(ipvsNodeportSvcs); i++ {
+					if !svc.local || (svc.local && endpoint.isLocal) {
+						err := nsc.ln.ipvsAddServer(ipvsNodeportSvcs[i], &dst)
+						if err != nil {
+							glog.Errorf(err.Error())
+						} else {
+							activeServiceEndpointMap[nodeServiceIds[i]] = append(activeServiceEndpointMap[nodeServiceIds[i]], endpoint.ip)
+						}
+					}
+				}
+			}
+
+			for _, externalIpService := range externalIpServices {
+				if svc.local && !endpoint.isLocal {
+					continue
+				}
+
+				if svc.directServerReturn && svc.directServerReturnMethod == "tunnel" {
+					dst.ConnectionFlags = ipvs.ConnectionFlagTunnel
+				}
+
+				// add server to IPVS service
+				err := nsc.ln.ipvsAddServer(externalIpService.ipvsSvc, &dst)
+				if err != nil {
+					glog.Errorf(err.Error())
+				}
+
+				// For now just support IPVS tunnel mode, we can add other ways of DSR in future
+				if svc.directServerReturn && svc.directServerReturnMethod == "tunnel" {
+
+					podObj, err := nsc.getPodObjectForEndpoint(endpoint.ip)
+					if err != nil {
+						glog.Errorf("Failed to find endpoint with ip: " + endpoint.ip + ". so skipping peparing endpoint for DSR")
+						continue
+					}
+
+					// we are only concerned with endpoint pod running on current node
+					if strings.Compare(podObj.Status.HostIP, nsc.nodeIP.String()) != 0 {
+						continue
+					}
+
+					containerID := strings.TrimPrefix(podObj.Status.ContainerStatuses[0].ContainerID, "docker://")
+					if containerID == "" {
+						glog.Errorf("Failed to find container id for the endpoint with ip: " + endpoint.ip + " so skipping peparing endpoint for DSR")
+						continue
+					}
+
+					err = nsc.ln.prepareEndpointForDsr(containerID, endpoint.ip, externalIpService.externalIp)
+					if err != nil {
+						glog.Errorf("Failed to prepare endpoint %s to do direct server return due to %s", endpoint.ip, err.Error())
+					}
+				}
+			}
+		}
+	}
+
+	// cleanup stale IPs on dummy interface
+	glog.V(1).Info("Cleaning up if any, old service IPs on dummy interface")
+	addrActive := make(map[string]bool)
+	for k := range activeServiceEndpointMap {
+		// verify active and its a generateIpPortId() type service
+		if strings.Contains(k, "-") {
+			parts := strings.SplitN(k, "-", 3)
+			addrActive[parts[0]] = true
+		}
+	}
+
+	var addrs []netlink.Addr
+	addrs, err = netlink.AddrList(dummyVipInterface, netlink.FAMILY_V4)
+	if err != nil {
+		return errors.New("Failed to list dummy interface IPs: " + err.Error())
+	}
+	for _, addr := range addrs {
+		isActive := addrActive[addr.IP.String()]
+		if !isActive {
+			glog.V(1).Infof("Found an IP %s which is no longer needed so cleaning up", addr.IP.String())
+			err := nsc.ln.ipAddrDel(dummyVipInterface, addr.IP.String())
+			if err != nil {
+				glog.Errorf("Failed to delete stale IP %s due to: %s",
+					addr.IP.String(), err.Error())
+				continue
+			}
+		}
+	}
+
+	// cleanup stale ipvs service and servers
+	glog.V(1).Info("Cleaning up if any, old ipvs service and servers which are no longer needed")
+	ipvsSvcs, err = nsc.ln.ipvsGetServices()
+
+	if err != nil {
+		return errors.New("Failed to list IPVS services: " + err.Error())
+	}
+	var protocol string
+	for _, ipvsSvc := range ipvsSvcs {
+		if ipvsSvc.Protocol == syscall.IPPROTO_TCP {
+			protocol = "tcp"
+		} else {
+			protocol = "udp"
+		}
+		var key string
+		if ipvsSvc.Address != nil {
+			key = generateIpPortId(ipvsSvc.Address.String(), protocol, strconv.Itoa(int(ipvsSvc.Port)))
+		} else if ipvsSvc.FWMark != 0 {
+			key = fmt.Sprint(ipvsSvc.FWMark)
+		} else {
+			continue
+		}
+
+		endpoints, ok := activeServiceEndpointMap[key]
+		// Only delete the service if it's not there anymore to prevent flapping
+		// old: if !ok || len(endpoints) == 0 {
+		if !ok {
+			glog.V(1).Infof("Found a IPVS service %s which is no longer needed so cleaning up",
+				ipvsServiceString(ipvsSvc))
+			err := nsc.ln.ipvsDelService(ipvsSvc)
+			if err != nil {
+				glog.Errorf("Failed to delete stale IPVS service %s due to: %s",
+					ipvsServiceString(ipvsSvc), err.Error())
+				continue
+			}
+		} else {
+			dsts, err := nsc.ln.ipvsGetDestinations(ipvsSvc)
+			if err != nil {
+				glog.Errorf("Failed to get list of servers from ipvs service")
+			}
+			for _, dst := range dsts {
+				validEp := false
+				for _, ep := range endpoints {
+					if ep == dst.Address.String() {
+						validEp = true
+						break
+					}
+				}
+				if !validEp {
+					glog.V(1).Infof("Found a destination %s in service %s which is no longer needed so cleaning up",
+						ipvsDestinationString(dst), ipvsServiceString(ipvsSvc))
+					err = nsc.ipvsDeleteDestination(ipvsSvc, dst)
+					if err != nil {
+						glog.Errorf("Failed to delete destination %s from ipvs service %s",
+							ipvsDestinationString(dst), ipvsServiceString(ipvsSvc))
+					}
+				}
+			}
+		}
+	}
+
+	err = nsc.syncIpvsFirewall()
+	if err != nil {
+		glog.Errorf("Error syncing ipvs svc iptables rules: %s", err.Error())
+	}
+
+	glog.V(1).Info("IPVS servers and services are synced to desired state")
+	return nil
+}
+
 func (nsc *NetworkServicesController) getPodObjectForEndpoint(endpointIP string) (*api.Pod, error) {
 	for _, obj := range nsc.podLister.List() {
 		pod := obj.(*api.Pod)