feat(smf): notify UPF to send endMarker when handover (#58)

internal/context/ngap_handler.go

@@ -1,15 +1,12 @@
 package context
 
 import (
-	"bytes"
 	"encoding/binary"
 	"errors"
-	"fmt"
 
 	"github.com/free5gc/aper"
 	"github.com/free5gc/ngap/ngapType"
 	"github.com/free5gc/openapi/models"
-	"github.com/free5gc/pfcp/pfcpType"
 	"github.com/free5gc/smf/internal/logger"
 )
 
@@ -29,25 +26,11 @@ func HandlePDUSessionResourceSetupResponseTransfer(b []byte, ctx *SMContext) (er
 		return errors.New("resourceSetupResponseTransfer.QosFlowPerTNLInformation.UPTransportLayerInformation.Present")
 	}
 
-	gtpTunnel := QosFlowPerTNLInformation.UPTransportLayerInformation.GTPTunnel
+	GTPTunnel := QosFlowPerTNLInformation.UPTransportLayerInformation.GTPTunnel
 
-	teid := binary.BigEndian.Uint32(gtpTunnel.GTPTEID.Value)
-
-	ctx.Tunnel.ANInformation.IPAddress = gtpTunnel.TransportLayerAddress.Value.Bytes
-	ctx.Tunnel.ANInformation.TEID = teid
-
-	for _, dataPath := range ctx.Tunnel.DataPathPool {
-		if dataPath.Activated {
-			ANUPF := dataPath.FirstDPNode
-			DLPDR := ANUPF.DownLinkTunnel.PDR
-
-			DLPDR.FAR.ForwardingParameters.OuterHeaderCreation = new(pfcpType.OuterHeaderCreation)
-			dlOuterHeaderCreation := DLPDR.FAR.ForwardingParameters.OuterHeaderCreation
-			dlOuterHeaderCreation.OuterHeaderCreationDescription = pfcpType.OuterHeaderCreationGtpUUdpIpv4
-			dlOuterHeaderCreation.Teid = teid
-			dlOuterHeaderCreation.Ipv4Address = ctx.Tunnel.ANInformation.IPAddress.To4()
-		}
-	}
+	ctx.Tunnel.UpdateANInformation(
+		GTPTunnel.TransportLayerAddress.Value.Bytes,
+		binary.BigEndian.Uint32(GTPTunnel.GTPTEID.Value))
 
 	ctx.UpCnxState = models.UpCnxState_ACTIVATED
 	return nil
@@ -99,26 +82,11 @@ func HandlePathSwitchRequestTransfer(b []byte, ctx *SMContext) error {
 		return errors.New("pathSwitchRequestTransfer.DLNGUUPTNLInformation.Present")
 	}
 
-	gtpTunnel := pathSwitchRequestTransfer.DLNGUUPTNLInformation.GTPTunnel
-
-	teid := binary.BigEndian.Uint32(gtpTunnel.GTPTEID.Value)
-
-	ctx.Tunnel.ANInformation.IPAddress = gtpTunnel.TransportLayerAddress.Value.Bytes
-	ctx.Tunnel.ANInformation.TEID = teid
+	GTPTunnel := pathSwitchRequestTransfer.DLNGUUPTNLInformation.GTPTunnel
 
-	for _, dataPath := range ctx.Tunnel.DataPathPool {
-		if dataPath.Activated {
-			ANUPF := dataPath.FirstDPNode
-			DLPDR := ANUPF.DownLinkTunnel.PDR
-
-			DLPDR.FAR.ForwardingParameters.OuterHeaderCreation = new(pfcpType.OuterHeaderCreation)
-			dlOuterHeaderCreation := DLPDR.FAR.ForwardingParameters.OuterHeaderCreation
-			dlOuterHeaderCreation.OuterHeaderCreationDescription = pfcpType.OuterHeaderCreationGtpUUdpIpv4
-			dlOuterHeaderCreation.Teid = teid
-			dlOuterHeaderCreation.Ipv4Address = ctx.Tunnel.ANInformation.IPAddress.To4()
-			DLPDR.FAR.State = RULE_UPDATE
-		}
-	}
+	ctx.Tunnel.UpdateANInformation(
+		GTPTunnel.TransportLayerAddress.Value.Bytes,
+		binary.BigEndian.Uint32(GTPTunnel.GTPTEID.Value))
 
 	ctx.UpSecurityFromPathSwitchRequestSameAsLocalStored = true
 
@@ -189,28 +157,12 @@ func HandleHandoverRequestAcknowledgeTransfer(b []byte, ctx *SMContext) (err err
 	if err != nil {
 		return err
 	}
-	DLNGUUPTNLInformation := handoverRequestAcknowledgeTransfer.DLNGUUPTNLInformation
-	GTPTunnel := DLNGUUPTNLInformation.GTPTunnel
-	TEIDReader := bytes.NewBuffer(GTPTunnel.GTPTEID.Value)
 
-	teid, err := binary.ReadUvarint(TEIDReader)
-	if err != nil {
-		return fmt.Errorf("Parse TEID error %s", err.Error())
-	}
+	DLNGUUPGTPTunnel := handoverRequestAcknowledgeTransfer.DLNGUUPTNLInformation.GTPTunnel
 
-	for _, dataPath := range ctx.Tunnel.DataPathPool {
-		if dataPath.Activated {
-			ANUPF := dataPath.FirstDPNode
-			DLPDR := ANUPF.DownLinkTunnel.PDR
-
-			DLPDR.FAR.ForwardingParameters.OuterHeaderCreation = new(pfcpType.OuterHeaderCreation)
-			dlOuterHeaderCreation := DLPDR.FAR.ForwardingParameters.OuterHeaderCreation
-			dlOuterHeaderCreation.OuterHeaderCreationDescription = pfcpType.OuterHeaderCreationGtpUUdpIpv4
-			dlOuterHeaderCreation.Teid = uint32(teid)
-			dlOuterHeaderCreation.Ipv4Address = GTPTunnel.TransportLayerAddress.Value.Bytes
-			DLPDR.FAR.State = RULE_UPDATE
-		}
-	}
+	ctx.Tunnel.UpdateANInformation(
+		DLNGUUPGTPTunnel.TransportLayerAddress.Value.Bytes,
+		binary.BigEndian.Uint32(DLNGUUPGTPTunnel.GTPTEID.Value))
 
 	return nil
 }

internal/context/pfcp_rules.go

@@ -55,6 +55,7 @@ type ForwardingParameters struct {
 	NetworkInstance      *pfcpType.NetworkInstance
 	OuterHeaderCreation  *pfcpType.OuterHeaderCreation
 	ForwardingPolicyID   string
+	SendEndMarker        bool
 }
 
 // Buffering Action Rule 7.5.2.6-1

internal/context/upf.go

@@ -30,6 +30,30 @@ type UPTunnel struct {
 	}
 }
 
+func (t *UPTunnel) UpdateANInformation(ip net.IP, teid uint32) {
+	t.ANInformation.IPAddress = ip
+	t.ANInformation.TEID = teid
+
+	for _, dataPath := range t.DataPathPool {
+		if dataPath.Activated {
+			ANUPF := dataPath.FirstDPNode
+			DLPDR := ANUPF.DownLinkTunnel.PDR
+
+			if DLPDR.FAR.ForwardingParameters.OuterHeaderCreation != nil {
+				// Old AN tunnel exists
+				DLPDR.FAR.ForwardingParameters.SendEndMarker = true
+			}
+
+			DLPDR.FAR.ForwardingParameters.OuterHeaderCreation = new(pfcpType.OuterHeaderCreation)
+			dlOuterHeaderCreation := DLPDR.FAR.ForwardingParameters.OuterHeaderCreation
+			dlOuterHeaderCreation.OuterHeaderCreationDescription = pfcpType.OuterHeaderCreationGtpUUdpIpv4
+			dlOuterHeaderCreation.Teid = t.ANInformation.TEID
+			dlOuterHeaderCreation.Ipv4Address = t.ANInformation.IPAddress.To4()
+			DLPDR.FAR.State = RULE_UPDATE
+		}
+	}
+}
+
 type UPFStatus int
 
 const (

internal/pfcp/message/build.go

@@ -119,16 +119,16 @@ func farToCreateFAR(far *context.FAR) *pfcp.CreateFAR {
 	}
 
 	if far.ForwardingParameters != nil {
-		createFAR.ForwardingParameters = new(pfcp.ForwardingParametersIEInFAR)
-		createFAR.ForwardingParameters.DestinationInterface = &far.ForwardingParameters.DestinationInterface
-		createFAR.ForwardingParameters.NetworkInstance = far.ForwardingParameters.NetworkInstance
-		createFAR.ForwardingParameters.OuterHeaderCreation = far.ForwardingParameters.OuterHeaderCreation
+		createFAR.ForwardingParameters = &pfcp.ForwardingParametersIEInFAR{
+			DestinationInterface: &far.ForwardingParameters.DestinationInterface,
+			NetworkInstance:      far.ForwardingParameters.NetworkInstance,
+			OuterHeaderCreation:  far.ForwardingParameters.OuterHeaderCreation,
+		}
 		if far.ForwardingParameters.ForwardingPolicyID != "" {
-			createFAR.ForwardingParameters.ForwardingPolicy = new(pfcpType.ForwardingPolicy)
-			createFAR.ForwardingParameters.ForwardingPolicy.ForwardingPolicyIdentifierLength =
-				uint8(len(far.ForwardingParameters.ForwardingPolicyID))
-			createFAR.ForwardingParameters.ForwardingPolicy.ForwardingPolicyIdentifier =
-				[]byte(far.ForwardingParameters.ForwardingPolicyID)
+			createFAR.ForwardingParameters.ForwardingPolicy = &pfcpType.ForwardingPolicy{
+				ForwardingPolicyIdentifierLength: uint8(len(far.ForwardingParameters.ForwardingPolicyID)),
+				ForwardingPolicyIdentifier:       []byte(far.ForwardingParameters.ForwardingPolicyID),
+			}
 		}
 	}
 
@@ -220,16 +220,19 @@ func farToUpdateFAR(far *context.FAR) *pfcp.UpdateFAR {
 	updateFAR.ApplyAction.Drop = far.ApplyAction.Drop
 
 	if far.ForwardingParameters != nil {
-		updateFAR.UpdateForwardingParameters = new(pfcp.UpdateForwardingParametersIEInFAR)
-		updateFAR.UpdateForwardingParameters.DestinationInterface = &far.ForwardingParameters.DestinationInterface
-		updateFAR.UpdateForwardingParameters.NetworkInstance = far.ForwardingParameters.NetworkInstance
-		updateFAR.UpdateForwardingParameters.OuterHeaderCreation = far.ForwardingParameters.OuterHeaderCreation
+		updateFAR.UpdateForwardingParameters = &pfcp.UpdateForwardingParametersIEInFAR{
+			DestinationInterface: &far.ForwardingParameters.DestinationInterface,
+			NetworkInstance:      far.ForwardingParameters.NetworkInstance,
+			OuterHeaderCreation:  far.ForwardingParameters.OuterHeaderCreation,
+			PFCPSMReqFlags: &pfcpType.PFCPSMReqFlags{
+				Sndem: far.ForwardingParameters.SendEndMarker,
+			},
+		}
 		if far.ForwardingParameters.ForwardingPolicyID != "" {
-			updateFAR.UpdateForwardingParameters.ForwardingPolicy = new(pfcpType.ForwardingPolicy)
-			updateFAR.UpdateForwardingParameters.ForwardingPolicy.ForwardingPolicyIdentifierLength =
-				uint8(len(far.ForwardingParameters.ForwardingPolicyID))
-			updateFAR.UpdateForwardingParameters.ForwardingPolicy.ForwardingPolicyIdentifier =
-				[]byte(far.ForwardingParameters.ForwardingPolicyID)
+			updateFAR.UpdateForwardingParameters.ForwardingPolicy = &pfcpType.ForwardingPolicy{
+				ForwardingPolicyIdentifierLength: uint8(len(far.ForwardingParameters.ForwardingPolicyID)),
+				ForwardingPolicyIdentifier:       []byte(far.ForwardingParameters.ForwardingPolicyID),
+			}
 		}
 	}
 
@@ -242,7 +245,8 @@ func BuildPfcpSessionEstablishmentRequest(
 	pdrList []*context.PDR,
 	farList []*context.FAR,
 	barList []*context.BAR,
-	qerList []*context.QER) (pfcp.PFCPSessionEstablishmentRequest, error) {
+	qerList []*context.QER,
+) (pfcp.PFCPSessionEstablishmentRequest, error) {
 	msg := pfcp.PFCPSessionEstablishmentRequest{}
 
 	msg.NodeID = &context.SMF_Self().CPNodeID
@@ -351,7 +355,8 @@ func BuildPfcpSessionModificationRequest(
 	pdrList []*context.PDR,
 	farList []*context.FAR,
 	barList []*context.BAR,
-	qerList []*context.QER) (pfcp.PFCPSessionModificationRequest, error) {
+	qerList []*context.QER,
+) (pfcp.PFCPSessionModificationRequest, error) {
 	msg := pfcp.PFCPSessionModificationRequest{}
 
 	msg.UpdatePDR = make([]*pfcp.UpdatePDR, 0, 2)