Support capturing only the dropped packet in live-traffic Traceflow

build/yamls/antrea-aks.yml

@@ -1291,6 +1291,11 @@ spec:
       name: Live-Traffic
       priority: 10
       type: boolean
+    - description: Capture only the dropped packet.
+      jsonPath: .spec.droppedOnly
+      name: Dropped-Only
+      priority: 10
+      type: boolean
     - description: Timeout in seconds.
       jsonPath: .spec.timeout
       name: Timeout
@@ -1317,6 +1322,8 @@ spec:
                   service:
                     type: string
                 type: object
+              droppedOnly:
+                type: boolean
               liveTraffic:
                 type: boolean
               packet:

build/yamls/antrea-eks.yml

@@ -1291,6 +1291,11 @@ spec:
       name: Live-Traffic
       priority: 10
       type: boolean
+    - description: Capture only the dropped packet.
+      jsonPath: .spec.droppedOnly
+      name: Dropped-Only
+      priority: 10
+      type: boolean
     - description: Timeout in seconds.
       jsonPath: .spec.timeout
       name: Timeout
@@ -1317,6 +1322,8 @@ spec:
                   service:
                     type: string
                 type: object
+              droppedOnly:
+                type: boolean
               liveTraffic:
                 type: boolean
               packet:

build/yamls/antrea-gke.yml

@@ -1291,6 +1291,11 @@ spec:
       name: Live-Traffic
       priority: 10
       type: boolean
+    - description: Capture only the dropped packet.
+      jsonPath: .spec.droppedOnly
+      name: Dropped-Only
+      priority: 10
+      type: boolean
     - description: Timeout in seconds.
       jsonPath: .spec.timeout
       name: Timeout
@@ -1317,6 +1322,8 @@ spec:
                   service:
                     type: string
                 type: object
+              droppedOnly:
+                type: boolean
               liveTraffic:
                 type: boolean
               packet:

build/yamls/antrea-ipsec.yml

@@ -1291,6 +1291,11 @@ spec:
       name: Live-Traffic
       priority: 10
       type: boolean
+    - description: Capture only the dropped packet.
+      jsonPath: .spec.droppedOnly
+      name: Dropped-Only
+      priority: 10
+      type: boolean
     - description: Timeout in seconds.
       jsonPath: .spec.timeout
       name: Timeout
@@ -1317,6 +1322,8 @@ spec:
                   service:
                     type: string
                 type: object
+              droppedOnly:
+                type: boolean
               liveTraffic:
                 type: boolean
               packet:

build/yamls/antrea.yml

@@ -1291,6 +1291,11 @@ spec:
       name: Live-Traffic
       priority: 10
       type: boolean
+    - description: Capture only the dropped packet.
+      jsonPath: .spec.droppedOnly
+      name: Dropped-Only
+      priority: 10
+      type: boolean
     - description: Timeout in seconds.
       jsonPath: .spec.timeout
       name: Timeout
@@ -1317,6 +1322,8 @@ spec:
                   service:
                     type: string
                 type: object
+              droppedOnly:
+                type: boolean
               liveTraffic:
                 type: boolean
               packet:

build/yamls/base/crds.yml

@@ -128,6 +128,11 @@ spec:
           name: Live-Traffic
           type: boolean
           priority: 10
+        - jsonPath: .spec.droppedOnly
+          description: Capture only the dropped packet.
+          name: Dropped-Only
+          type: boolean
+          priority: 10
         - jsonPath: .spec.timeout
           description: Timeout in seconds.
           name: Timeout
@@ -222,6 +227,8 @@ spec:
                               type: integer
                 liveTraffic:
                   type: boolean
+                droppedOnly:
+                  type: boolean
                 timeout:
                   type: integer
             status:

pkg/agent/controller/traceflow/packetin.go

@@ -53,7 +53,9 @@ func (c *Controller) HandlePacketIn(pktIn *ofctrl.PacketIn) error {
 		}
 		update := tf.DeepCopy()
 		update.Status.Results = append(update.Status.Results, *nodeResult)
-		update.Status.CapturedPacket = packet
+		if packet != nil {
+			update.Status.CapturedPacket = packet
+		}
 		_, err = c.traceflowClient.CrdV1alpha1().Traceflows().UpdateStatus(context.TODO(), update, v1.UpdateOptions{})
 		if err != nil {
 			klog.Warningf("Update traceflow failed: %+v", err)
@@ -108,7 +110,10 @@ func (c *Controller) parsePacketIn(pktIn *ofctrl.PacketIn) (*crdv1alpha1.Tracefl
 		// Uninstall the OVS flows after receiving the first packet, to
 		// avoid capturing too many matched packets.
 		c.ofClient.UninstallTraceflowFlows(tag)
-		if tfState.isSender {
+		// Report the captured dropped packet, if the Traceflow is for
+		// the dropped packet only; otherwise only the sender reports
+		// the first captured packet.
+		if tfState.isSender || tfState.droppedOnly {
 			capturedPacket = parseCapturedPacket(pktIn)
 		}
 	}

pkg/agent/controller/traceflow/traceflow_controller.go

@@ -74,6 +74,7 @@ type traceflowState struct {
 	name        string
 	tag         uint8
 	liveTraffic bool
+	droppedOnly bool
 	isSender    bool
 	// Agent received the first Traceflow packet from OVS.
 	receivedPacket bool
@@ -308,6 +309,9 @@ func (c *Controller) startTraceflow(tf *crdv1alpha1.Traceflow) error {
 		srcOFPort = uint32(podInterfaces[0].OFPort)
 		// On the source Node, trace the first packet of the first
 		// connection that matches the Traceflow spec.
+		// TODO: support specifying only the Destination Pod for
+		// live-traffic Traceflow, which will trace the matched traffic
+		// to the destination Pod from any source.
 		if liveTraffic {
 			matchPacket = packet
 		}
@@ -316,7 +320,10 @@ func (c *Controller) startTraceflow(tf *crdv1alpha1.Traceflow) error {
 
 	// Store Traceflow to cache.
 	c.runningTraceflowsMutex.Lock()
-	tfState := traceflowState{name: tf.Name, tag: tf.Status.DataplaneTag, liveTraffic: tf.Spec.LiveTraffic, isSender: isSender}
+	tfState := traceflowState{
+		name: tf.Name, tag: tf.Status.DataplaneTag,
+		liveTraffic: liveTraffic, droppedOnly: tf.Spec.DroppedOnly && liveTraffic,
+		isSender: isSender}
 	c.runningTraceflows[tfState.tag] = &tfState
 	c.runningTraceflowsMutex.Unlock()
 
@@ -326,7 +333,7 @@ func (c *Controller) startTraceflow(tf *crdv1alpha1.Traceflow) error {
 	if timeout == 0 {
 		timeout = crdv1alpha1.DefaultTraceflowTimeout
 	}
-	err = c.ofClient.InstallTraceflowFlows(tfState.tag, liveTraffic, matchPacket, srcOFPort, timeout)
+	err = c.ofClient.InstallTraceflowFlows(tfState.tag, liveTraffic, tfState.droppedOnly, matchPacket, srcOFPort, timeout)
 	if err != nil {
 		return err
 	}
@@ -506,8 +513,8 @@ func (c *Controller) preparePacket(tf *crdv1alpha1.Traceflow, intf *interfacesto
 		}
 	}
 
-	if packet.IPProto == 0 || packet.IPProto == protocol.Type_ICMP || packet.IPProto == protocol.Type_IPv6ICMP {
-		// IPProto defaults to ICMP.
+	// Defaults to ICMP if not live-traffic Traceflow.
+	if packet.IPProto == 0 && !liveTraffic || packet.IPProto == protocol.Type_ICMP || packet.IPProto == protocol.Type_IPv6ICMP {
 		isICMP = true
 	}
 	if isICMP {

pkg/agent/openflow/client.go

@@ -227,7 +227,7 @@ type Client interface {
 	SendTraceflowPacket(dataplaneTag uint8, packet *binding.Packet, inPort uint32, outPort int32) error
 
 	// InstallTraceflowFlows installs flows for a Traceflow request.
-	InstallTraceflowFlows(dataplaneTag uint8, liveTraffic bool, packet *binding.Packet, srcOFPort uint32, timeoutSeconds uint16) error
+	InstallTraceflowFlows(dataplaneTag uint8, liveTraffic, droppedOnly bool, packet *binding.Packet, srcOFPort uint32, timeoutSeconds uint16) error
 
 	// UninstallTraceflowFlows uninstalls flows for a Traceflow request.
 	UninstallTraceflowFlows(dataplaneTag uint8) error
@@ -860,11 +860,11 @@ func (c *client) SendTraceflowPacket(dataplaneTag uint8, packet *binding.Packet,
 	return c.bridge.SendPacketOut(packetOutObj)
 }
 
-func (c *client) InstallTraceflowFlows(dataplaneTag uint8, liveTraffic bool, packet *binding.Packet, srcOFPort uint32, timeoutSeconds uint16) error {
+func (c *client) InstallTraceflowFlows(dataplaneTag uint8, liveTraffic, droppedOnly bool, packet *binding.Packet, srcOFPort uint32, timeoutSeconds uint16) error {
 	cacheKey := fmt.Sprintf("%x", dataplaneTag)
 	flows := []binding.Flow{}
 	flows = append(flows, c.traceflowConnectionTrackFlows(dataplaneTag, packet, srcOFPort, timeoutSeconds, cookie.Default)...)
-	flows = append(flows, c.traceflowL2ForwardOutputFlows(dataplaneTag, liveTraffic, timeoutSeconds, cookie.Default)...)
+	flows = append(flows, c.traceflowL2ForwardOutputFlows(dataplaneTag, liveTraffic, droppedOnly, timeoutSeconds, cookie.Default)...)
 	flows = append(flows, c.traceflowNetworkPolicyFlows(dataplaneTag, timeoutSeconds, cookie.Default)...)
 	return c.addFlows(c.tfFlowCache, cacheKey, flows)
 }

pkg/agent/openflow/client_test.go

@@ -280,7 +280,7 @@ func Test_client_InstallTraceflowFlows(t *testing.T) {
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			c := tt.prepareFunc(ctrl)
-			if err := c.InstallTraceflowFlows(tt.args.dataplaneTag, false, nil, 0, 300); (err != nil) != tt.wantErr {
+			if err := c.InstallTraceflowFlows(tt.args.dataplaneTag, false, false, nil, 0, 300); (err != nil) != tt.wantErr {
 				t.Errorf("InstallTraceflowFlows() error = %v, wantErr %v", err, tt.wantErr)
 			}
 		})

pkg/agent/openflow/pipeline.go

@@ -936,89 +936,98 @@ func (c *client) l2ForwardCalcFlow(dstMAC net.HardwareAddr, ofPort uint32, skipI
 
 // traceflowL2ForwardOutputFlows generates Traceflow specific flows that outputs traceflow packets
 // to OVS port and Antrea Agent after L2forwarding calculation.
-func (c *client) traceflowL2ForwardOutputFlows(dataplaneTag uint8, liveTraffic bool, timeout uint16, category cookie.Category) []binding.Flow {
+func (c *client) traceflowL2ForwardOutputFlows(dataplaneTag uint8, liveTraffic, droppedOnly bool, timeout uint16, category cookie.Category) []binding.Flow {
 	flows := []binding.Flow{}
 	l2FwdOutTable := c.pipeline[L2ForwardingOutTable]
 	for _, ipProtocol := range []binding.Protocol{binding.ProtocolIP, binding.ProtocolIPv6} {
 		if c.encapMode.SupportsEncap() {
 			// SendToController and Output if output port is tunnel port.
-			flows = append(flows, l2FwdOutTable.BuildFlow(priorityNormal+3).
+			fb1 := l2FwdOutTable.BuildFlow(priorityNormal+3).
 				MatchReg(int(PortCacheReg), config.DefaultTunOFPort).
 				MatchIPDSCP(dataplaneTag).
 				SetHardTimeout(timeout).
 				MatchProtocol(ipProtocol).
 				MatchRegRange(int(marksReg), portFoundMark, ofPortMarkRange).
 				Action().OutputRegRange(int(PortCacheReg), ofPortRegRange).
-				Action().SendToController(uint8(PacketInReasonTF)).
-				Cookie(c.cookieAllocator.Request(category).Raw()).
-				Done())
+				Cookie(c.cookieAllocator.Request(category).Raw())
 			// For injected packets, only SendToController if output port is local
 			// gateway. In encapMode, a Traceflow packet going out of the gateway
 			// port (i.e. exiting the overlay) essentially means that the Traceflow
 			// request is complete.
-			flowBuilder := l2FwdOutTable.BuildFlow(priorityNormal+2).
+			fb2 := l2FwdOutTable.BuildFlow(priorityNormal+2).
 				MatchReg(int(PortCacheReg), config.HostGatewayOFPort).
 				MatchIPDSCP(dataplaneTag).
 				SetHardTimeout(timeout).
 				MatchProtocol(ipProtocol).
 				MatchRegRange(int(marksReg), portFoundMark, ofPortMarkRange).
-				Action().SendToController(uint8(PacketInReasonTF)).
 				Cookie(c.cookieAllocator.Request(category).Raw())
+
+			// Do not send to controller if captures only dropped packet.
+			if !droppedOnly {
+				fb1 = fb1.Action().SendToController(uint8(PacketInReasonTF))
+				fb2 = fb2.Action().SendToController(uint8(PacketInReasonTF))
+			}
 			if liveTraffic {
 				// Clear the loaded DSCP bits before output.
-				flowBuilder = flowBuilder.Action().LoadIPDSCP(0).
+				fb2 = fb2.Action().LoadIPDSCP(0).
 					Action().OutputRegRange(int(PortCacheReg), ofPortRegRange)
 			}
-			flows = append(flows, flowBuilder.Done())
+			flows = append(flows, fb1.Done(), fb2.Done())
 		} else {
 			// SendToController and Output if output port is local gateway. Unlike in
 			// encapMode, inter-Node Pod-to-Pod traffic is expected to go out of the
 			// gateway port on the way to its destination.
-			flows = append(flows, l2FwdOutTable.BuildFlow(priorityNormal+2).
+			fb1 := l2FwdOutTable.BuildFlow(priorityNormal+2).
 				MatchReg(int(PortCacheReg), config.HostGatewayOFPort).
 				MatchIPDSCP(dataplaneTag).
 				SetHardTimeout(timeout).
 				MatchProtocol(ipProtocol).
 				MatchRegRange(int(marksReg), portFoundMark, ofPortMarkRange).
 				Action().OutputRegRange(int(PortCacheReg), ofPortRegRange).
-				Action().SendToController(uint8(PacketInReasonTF)).
-				Cookie(c.cookieAllocator.Request(category).Raw()).
-				Done())
+				Cookie(c.cookieAllocator.Request(category).Raw())
+			if !droppedOnly {
+				fb1 = fb1.Action().SendToController(uint8(PacketInReasonTF))
+			}
+			flows = append(flows, fb1.Done())
 		}
 		// Only SendToController if output port is local gateway and destination IP is gateway.
 		gatewayIP := c.nodeConfig.GatewayConfig.IPv4
 		if ipProtocol == binding.ProtocolIPv6 {
 			gatewayIP = c.nodeConfig.GatewayConfig.IPv6
 		}
 		if gatewayIP != nil {
-			flowBuilder := l2FwdOutTable.BuildFlow(priorityNormal+3).
+			fb := l2FwdOutTable.BuildFlow(priorityNormal+3).
 				MatchReg(int(PortCacheReg), config.HostGatewayOFPort).
 				MatchDstIP(gatewayIP).
 				MatchIPDSCP(dataplaneTag).
 				SetHardTimeout(timeout).
 				MatchProtocol(ipProtocol).
 				MatchRegRange(int(marksReg), portFoundMark, ofPortMarkRange).
-				Action().SendToController(uint8(PacketInReasonTF)).
 				Cookie(c.cookieAllocator.Request(category).Raw())
+			if !droppedOnly {
+				fb = fb.Action().SendToController(uint8(PacketInReasonTF))
+			}
 			if liveTraffic {
-				flowBuilder = flowBuilder.Action().LoadIPDSCP(0).
+				fb = fb.Action().LoadIPDSCP(0).
 					Action().OutputRegRange(int(PortCacheReg), ofPortRegRange)
 			}
-			flows = append(flows, flowBuilder.Done())
+			flows = append(flows, fb.Done())
 		}
 		// Only SendToController if output port is Pod port.
-		flowBuilder := l2FwdOutTable.BuildFlow(priorityNormal+2).
+		fb := l2FwdOutTable.BuildFlow(priorityNormal+2).
 			MatchIPDSCP(dataplaneTag).
 			SetHardTimeout(timeout).
 			MatchProtocol(ipProtocol).
 			MatchRegRange(int(marksReg), portFoundMark, ofPortMarkRange).
-			Action().SendToController(uint8(PacketInReasonTF)).
 			Cookie(c.cookieAllocator.Request(category).Raw())
+		if !droppedOnly {
+			fb = fb.Action().SendToController(uint8(PacketInReasonTF))
+		}
 		if liveTraffic {
-			flowBuilder = flowBuilder.Action().LoadIPDSCP(0).
+			fb = fb.Action().LoadIPDSCP(0).
 				Action().OutputRegRange(int(PortCacheReg), ofPortRegRange)
 		}
-		flows = append(flows, flowBuilder.Done())
+		flows = append(flows, fb.Done())
 	}
 	return flows
 }