Merge pull request #63 from LakshK98/test-pr

Test pr

Author: lakshk98

pkg/plugin/ebpfwindows/datapath_drop_windows.go

@@ -19,17 +19,23 @@ const (
 
 const (
 	// dropNotifyV1Len is the amount of packet data provided in a v0/v1 drop notification.
-	dropNotifyV1Len = 36
+	dropNotifyV1Len       = 36
+	dropPktmonNotifyV1Len = 57
 )
 
 var dropNotifyLengthFromVersion = map[uint16]uint{
 	DropNotifyVersion0: dropNotifyV1Len, // retain backwards compatibility for testing.
 	DropNotifyVersion1: dropNotifyV1Len,
 }
 
+var pktmonDropNotifyLengthFromVersion = map[uint16]uint{
+	DropNotifyVersion1: dropPktmonNotifyV1Len,
+}
+
 var (
-	errUnexpectedDropNotifyLength = errors.New("unexpected DropNotify data length")
-	errInvalidDropNotifyVersion   = errors.New("invalid DropNotify version")
+	errUnexpectedDropNotifyLength     = errors.New("unexpected DropNotify data length")
+	errInvalidDropNotifyVersion       = errors.New("invalid DropNotify version")
+	errInvalidPktmonDropNotifyVersion = errors.New("invalid Pktmon DropNotify version")
 )
 
 // DropNotify is the message format of a drop notification in the BPF ring buffer
@@ -50,6 +56,90 @@ type DropNotify struct {
 	Ifindex  uint32
 }
 
+type NetEventDataHeader struct {
+	Type    uint8
+	Version uint16
+}
+
+type PktmonEvtStreamPacketDescriptor struct {
+	PacketOriginalLength uint32
+	PacketLoggedLength   uint32
+	PacketMetadataLength uint32
+}
+
+type PktmonEvtStreamMetadata struct {
+	PktGroupID      uint64
+	PktCount        uint16
+	AppearanceCount uint16
+	DirectionName   uint16
+	PacketType      uint16
+	ComponentID     uint16
+	EdgeID          uint16
+	FilterID        uint16
+	DropReason      uint32
+	DropLocation    uint32
+	ProcNum         uint16
+	Timestamp       uint64
+}
+
+type PktmonEvtStreamPacketHeader struct {
+	EventID          uint8
+	PacketDescriptor PktmonEvtStreamPacketDescriptor
+	Metadata         PktmonEvtStreamMetadata
+}
+
+type PktmonDropNotify struct {
+	VersionHeader NetEventDataHeader
+	PktmonHeader  PktmonEvtStreamPacketHeader
+}
+
+// DecodePktmonDrop will decode 'data' into the provided DropNotify structure
+func DecodePktmonDrop(data []byte, pdn *PktmonDropNotify) error {
+	if err := pdn.decodePktmonDrop(data); err != nil {
+		return err
+	}
+	return nil
+}
+
+// DataOffset returns the offset from the beginning of PktmonDropNotify where the
+// notification data begins.
+func (n *PktmonDropNotify) DataOffset() uint {
+	return pktmonDropNotifyLengthFromVersion[n.VersionHeader.Version]
+}
+
+func (n *PktmonDropNotify) decodePktmonDrop(data []byte) error {
+	if l := len(data); l < dropPktmonNotifyV1Len {
+		return fmt.Errorf("%w: expected at least %d but got %d", errUnexpectedDropNotifyLength, dropPktmonNotifyV1Len, l)
+	}
+	version := byteorder.Native.Uint16(data[2:4])
+
+	// Check against max version.
+	if version > DropNotifyVersion1 {
+		return fmt.Errorf("%w: Unrecognized drop event version %d", errInvalidPktmonDropNotifyVersion, version)
+	}
+
+	// Decode logic for version = v1.
+	n.VersionHeader.Type = data[0]
+	n.VersionHeader.Version = version
+	n.PktmonHeader.EventID = data[4]
+	n.PktmonHeader.PacketDescriptor.PacketOriginalLength = byteorder.Native.Uint32(data[5:9])
+	n.PktmonHeader.PacketDescriptor.PacketLoggedLength = byteorder.Native.Uint32(data[9:13])
+	n.PktmonHeader.PacketDescriptor.PacketMetadataLength = byteorder.Native.Uint32(data[13:17])
+	n.PktmonHeader.Metadata.PktGroupID = byteorder.Native.Uint64(data[17:25])
+	n.PktmonHeader.Metadata.PktCount = byteorder.Native.Uint16(data[25:27])
+	n.PktmonHeader.Metadata.AppearanceCount = byteorder.Native.Uint16(data[27:29])
+	n.PktmonHeader.Metadata.DirectionName = byteorder.Native.Uint16(data[29:31])
+	n.PktmonHeader.Metadata.PacketType = byteorder.Native.Uint16(data[31:33])
+	n.PktmonHeader.Metadata.ComponentID = byteorder.Native.Uint16(data[33:35])
+	n.PktmonHeader.Metadata.EdgeID = byteorder.Native.Uint16(data[35:37])
+	n.PktmonHeader.Metadata.FilterID = byteorder.Native.Uint16(data[37:39])
+	n.PktmonHeader.Metadata.DropReason = byteorder.Native.Uint32(data[39:43])
+	n.PktmonHeader.Metadata.DropLocation = byteorder.Native.Uint32(data[43:47])
+	n.PktmonHeader.Metadata.ProcNum = byteorder.Native.Uint16(data[47:49])
+	n.PktmonHeader.Metadata.Timestamp = byteorder.Native.Uint64(data[49:57])
+	return nil
+}
+
 // DecodeDropNotify will decode 'data' into the provided DropNotify structure
 func DecodeDropNotify(data []byte, dn *DropNotify) error {
 	return dn.decodeDropNotify(data)

pkg/plugin/ebpfwindows/ebpf_windows.go

@@ -307,6 +307,34 @@ func (p *Plugin) handleTraceEvent(data unsafe.Pointer, size uint32) error {
 		}
 		utils.AddRetinaMetadata(fl, meta)
 		p.enricher.Write(e)
+
+	case MessageTypePktmonDrop:
+		if size <= uint32(unsafe.Sizeof(PktmonDropNotify{})) {
+			return fmt.Errorf("%w: %d", errInvalidDropNotifySize, size)
+		}
+
+		e, err := p.parser.Decode(&observer.MonitorEvent{
+			Payload: &observer.PerfEvent{
+				Data: perfData,
+			},
+		})
+		if err != nil {
+			return fmt.Errorf("could not convert pktmon dropnotify event to flow: %w", err)
+		}
+		meta := &utils.RetinaMetadata{}
+		utils.AddPacketSize(meta, size-uint32(unsafe.Sizeof(DropNotify{})))
+		fl := e.GetFlow()
+		if fl == nil {
+			return fmt.Errorf("%w", errNilDropNotifyFlow)
+		}
+		if fl.GetEventType() == nil {
+			return fmt.Errorf("%w", errNilDropNotifyEvent)
+		}
+		// Set the drop reason.
+		eventType := fl.GetEventType().GetSubType()
+		meta.DropReason = utils.DropReason(eventType)
+		utils.AddRetinaMetadata(fl, meta)
+		p.enricher.Write(e)
 	}
 	return nil
 }