--- /dev/null
+// Copyright 2012 Google, Inc. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree.
+
+package layers
+
+import (
+ "encoding/binary"
+ "errors"
+ "fmt"
+ "hash/crc32"
+
+ "github.com/google/gopacket"
+)
+
+// SCTP contains information on the top level of an SCTP packet.
+type SCTP struct {
+ BaseLayer
+ SrcPort, DstPort SCTPPort
+ VerificationTag uint32
+ Checksum uint32
+ sPort, dPort []byte
+}
+
+// LayerType returns gopacket.LayerTypeSCTP
+func (s *SCTP) LayerType() gopacket.LayerType { return LayerTypeSCTP }
+
+func decodeSCTP(data []byte, p gopacket.PacketBuilder) error {
+ sctp := &SCTP{}
+ err := sctp.DecodeFromBytes(data, p)
+ p.AddLayer(sctp)
+ p.SetTransportLayer(sctp)
+ if err != nil {
+ return err
+ }
+ return p.NextDecoder(sctpChunkTypePrefixDecoder)
+}
+
+var sctpChunkTypePrefixDecoder = gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix)
+
+// TransportFlow returns a flow based on the source and destination SCTP port.
+func (s *SCTP) TransportFlow() gopacket.Flow {
+ return gopacket.NewFlow(EndpointSCTPPort, s.sPort, s.dPort)
+}
+
+func decodeWithSCTPChunkTypePrefix(data []byte, p gopacket.PacketBuilder) error {
+ chunkType := SCTPChunkType(data[0])
+ return chunkType.Decode(data, p)
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (s SCTP) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ bytes, err := b.PrependBytes(12)
+ if err != nil {
+ return err
+ }
+ binary.BigEndian.PutUint16(bytes[0:2], uint16(s.SrcPort))
+ binary.BigEndian.PutUint16(bytes[2:4], uint16(s.DstPort))
+ binary.BigEndian.PutUint32(bytes[4:8], s.VerificationTag)
+ if opts.ComputeChecksums {
+ // Note: MakeTable(Castagnoli) actually only creates the table once, then
+ // passes back a singleton on every other call, so this shouldn't cause
+ // excessive memory allocation.
+ binary.LittleEndian.PutUint32(bytes[8:12], crc32.Checksum(b.Bytes(), crc32.MakeTable(crc32.Castagnoli)))
+ }
+ return nil
+}
+
+func (sctp *SCTP) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+ if len(data) < 12 {
+ return errors.New("Invalid SCTP common header length")
+ }
+ sctp.SrcPort = SCTPPort(binary.BigEndian.Uint16(data[:2]))
+ sctp.sPort = data[:2]
+ sctp.DstPort = SCTPPort(binary.BigEndian.Uint16(data[2:4]))
+ sctp.dPort = data[2:4]
+ sctp.VerificationTag = binary.BigEndian.Uint32(data[4:8])
+ sctp.Checksum = binary.BigEndian.Uint32(data[8:12])
+ sctp.BaseLayer = BaseLayer{data[:12], data[12:]}
+
+ return nil
+}
+
+func (t *SCTP) CanDecode() gopacket.LayerClass {
+ return LayerTypeSCTP
+}
+
+func (t *SCTP) NextLayerType() gopacket.LayerType {
+ return gopacket.LayerTypePayload
+}
+
+// SCTPChunk contains the common fields in all SCTP chunks.
+type SCTPChunk struct {
+ BaseLayer
+ Type SCTPChunkType
+ Flags uint8
+ Length uint16
+ // ActualLength is the total length of an SCTP chunk, including padding.
+ // SCTP chunks start and end on 4-byte boundaries. So if a chunk has a length
+ // of 18, it means that it has data up to and including byte 18, then padding
+ // up to the next 4-byte boundary, 20. In this case, Length would be 18, and
+ // ActualLength would be 20.
+ ActualLength int
+}
+
+func roundUpToNearest4(i int) int {
+ if i%4 == 0 {
+ return i
+ }
+ return i + 4 - (i % 4)
+}
+
+func decodeSCTPChunk(data []byte) (SCTPChunk, error) {
+ length := binary.BigEndian.Uint16(data[2:4])
+ if length < 4 {
+ return SCTPChunk{}, errors.New("invalid SCTP chunk length")
+ }
+ actual := roundUpToNearest4(int(length))
+ ct := SCTPChunkType(data[0])
+
+ // For SCTP Data, use a separate layer for the payload
+ delta := 0
+ if ct == SCTPChunkTypeData {
+ delta = int(actual) - int(length)
+ actual = 16
+ }
+
+ return SCTPChunk{
+ Type: ct,
+ Flags: data[1],
+ Length: length,
+ ActualLength: actual,
+ BaseLayer: BaseLayer{data[:actual], data[actual : len(data)-delta]},
+ }, nil
+}
+
+// SCTPParameter is a TLV parameter inside a SCTPChunk.
+type SCTPParameter struct {
+ Type uint16
+ Length uint16
+ ActualLength int
+ Value []byte
+}
+
+func decodeSCTPParameter(data []byte) SCTPParameter {
+ length := binary.BigEndian.Uint16(data[2:4])
+ return SCTPParameter{
+ Type: binary.BigEndian.Uint16(data[0:2]),
+ Length: length,
+ Value: data[4:length],
+ ActualLength: roundUpToNearest4(int(length)),
+ }
+}
+
+func (p SCTPParameter) Bytes() []byte {
+ length := 4 + len(p.Value)
+ data := make([]byte, roundUpToNearest4(length))
+ binary.BigEndian.PutUint16(data[0:2], p.Type)
+ binary.BigEndian.PutUint16(data[2:4], uint16(length))
+ copy(data[4:], p.Value)
+ return data
+}
+
+// SCTPUnknownChunkType is the layer type returned when we don't recognize the
+// chunk type. Since there's a length in a known location, we can skip over
+// it even if we don't know what it is, and continue parsing the rest of the
+// chunks. This chunk is stored as an ErrorLayer in the packet.
+type SCTPUnknownChunkType struct {
+ SCTPChunk
+ bytes []byte
+}
+
+func decodeSCTPChunkTypeUnknown(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPUnknownChunkType{SCTPChunk: chunk}
+ sc.bytes = data[:sc.ActualLength]
+ p.AddLayer(sc)
+ p.SetErrorLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (s SCTPUnknownChunkType) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ bytes, err := b.PrependBytes(s.ActualLength)
+ if err != nil {
+ return err
+ }
+ copy(bytes, s.bytes)
+ return nil
+}
+
+// LayerType returns gopacket.LayerTypeSCTPUnknownChunkType.
+func (s *SCTPUnknownChunkType) LayerType() gopacket.LayerType { return LayerTypeSCTPUnknownChunkType }
+
+// Payload returns all bytes in this header, including the decoded Type, Length,
+// and Flags.
+func (s *SCTPUnknownChunkType) Payload() []byte { return s.bytes }
+
+// Error implements ErrorLayer.
+func (s *SCTPUnknownChunkType) Error() error {
+ return fmt.Errorf("No decode method available for SCTP chunk type %s", s.Type)
+}
+
+// SCTPData is the SCTP Data chunk layer.
+type SCTPData struct {
+ SCTPChunk
+ Unordered, BeginFragment, EndFragment bool
+ TSN uint32
+ StreamId uint16
+ StreamSequence uint16
+ PayloadProtocol SCTPPayloadProtocol
+}
+
+// LayerType returns gopacket.LayerTypeSCTPData.
+func (s *SCTPData) LayerType() gopacket.LayerType { return LayerTypeSCTPData }
+
+// SCTPPayloadProtocol represents a payload protocol
+type SCTPPayloadProtocol uint32
+
+// SCTPPayloadProtocol constonts from http://www.iana.org/assignments/sctp-parameters/sctp-parameters.xhtml
+const (
+ SCTPProtocolReserved SCTPPayloadProtocol = 0
+ SCTPPayloadUIA = 1
+ SCTPPayloadM2UA = 2
+ SCTPPayloadM3UA = 3
+ SCTPPayloadSUA = 4
+ SCTPPayloadM2PA = 5
+ SCTPPayloadV5UA = 6
+ SCTPPayloadH248 = 7
+ SCTPPayloadBICC = 8
+ SCTPPayloadTALI = 9
+ SCTPPayloadDUA = 10
+ SCTPPayloadASAP = 11
+ SCTPPayloadENRP = 12
+ SCTPPayloadH323 = 13
+ SCTPPayloadQIPC = 14
+ SCTPPayloadSIMCO = 15
+ SCTPPayloadDDPSegment = 16
+ SCTPPayloadDDPStream = 17
+ SCTPPayloadS1AP = 18
+)
+
+func (p SCTPPayloadProtocol) String() string {
+ switch p {
+ case SCTPProtocolReserved:
+ return "Reserved"
+ case SCTPPayloadUIA:
+ return "UIA"
+ case SCTPPayloadM2UA:
+ return "M2UA"
+ case SCTPPayloadM3UA:
+ return "M3UA"
+ case SCTPPayloadSUA:
+ return "SUA"
+ case SCTPPayloadM2PA:
+ return "M2PA"
+ case SCTPPayloadV5UA:
+ return "V5UA"
+ case SCTPPayloadH248:
+ return "H.248"
+ case SCTPPayloadBICC:
+ return "BICC"
+ case SCTPPayloadTALI:
+ return "TALI"
+ case SCTPPayloadDUA:
+ return "DUA"
+ case SCTPPayloadASAP:
+ return "ASAP"
+ case SCTPPayloadENRP:
+ return "ENRP"
+ case SCTPPayloadH323:
+ return "H.323"
+ case SCTPPayloadQIPC:
+ return "QIPC"
+ case SCTPPayloadSIMCO:
+ return "SIMCO"
+ case SCTPPayloadDDPSegment:
+ return "DDPSegment"
+ case SCTPPayloadDDPStream:
+ return "DDPStream"
+ case SCTPPayloadS1AP:
+ return "S1AP"
+ }
+ return fmt.Sprintf("Unknown(%d)", p)
+}
+
+func decodeSCTPData(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPData{
+ SCTPChunk: chunk,
+ Unordered: data[1]&0x4 != 0,
+ BeginFragment: data[1]&0x2 != 0,
+ EndFragment: data[1]&0x1 != 0,
+ TSN: binary.BigEndian.Uint32(data[4:8]),
+ StreamId: binary.BigEndian.Uint16(data[8:10]),
+ StreamSequence: binary.BigEndian.Uint16(data[10:12]),
+ PayloadProtocol: SCTPPayloadProtocol(binary.BigEndian.Uint32(data[12:16])),
+ }
+ // Length is the length in bytes of the data, INCLUDING the 16-byte header.
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.LayerTypePayload)
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPData) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ payload := b.Bytes()
+ // Pad the payload to a 32 bit boundary
+ if rem := len(payload) % 4; rem != 0 {
+ b.AppendBytes(4 - rem)
+ }
+ length := 16
+ bytes, err := b.PrependBytes(length)
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ flags := uint8(0)
+ if sc.Unordered {
+ flags |= 0x4
+ }
+ if sc.BeginFragment {
+ flags |= 0x2
+ }
+ if sc.EndFragment {
+ flags |= 0x1
+ }
+ bytes[1] = flags
+ binary.BigEndian.PutUint16(bytes[2:4], uint16(length+len(payload)))
+ binary.BigEndian.PutUint32(bytes[4:8], sc.TSN)
+ binary.BigEndian.PutUint16(bytes[8:10], sc.StreamId)
+ binary.BigEndian.PutUint16(bytes[10:12], sc.StreamSequence)
+ binary.BigEndian.PutUint32(bytes[12:16], uint32(sc.PayloadProtocol))
+ return nil
+}
+
+// SCTPInitParameter is a parameter for an SCTP Init or InitAck packet.
+type SCTPInitParameter SCTPParameter
+
+// SCTPInit is used as the return value for both SCTPInit and SCTPInitAck
+// messages.
+type SCTPInit struct {
+ SCTPChunk
+ InitiateTag uint32
+ AdvertisedReceiverWindowCredit uint32
+ OutboundStreams, InboundStreams uint16
+ InitialTSN uint32
+ Parameters []SCTPInitParameter
+}
+
+// LayerType returns either gopacket.LayerTypeSCTPInit or gopacket.LayerTypeSCTPInitAck.
+func (sc *SCTPInit) LayerType() gopacket.LayerType {
+ if sc.Type == SCTPChunkTypeInitAck {
+ return LayerTypeSCTPInitAck
+ }
+ // sc.Type == SCTPChunkTypeInit
+ return LayerTypeSCTPInit
+}
+
+func decodeSCTPInit(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPInit{
+ SCTPChunk: chunk,
+ InitiateTag: binary.BigEndian.Uint32(data[4:8]),
+ AdvertisedReceiverWindowCredit: binary.BigEndian.Uint32(data[8:12]),
+ OutboundStreams: binary.BigEndian.Uint16(data[12:14]),
+ InboundStreams: binary.BigEndian.Uint16(data[14:16]),
+ InitialTSN: binary.BigEndian.Uint32(data[16:20]),
+ }
+ paramData := data[20:sc.ActualLength]
+ for len(paramData) > 0 {
+ p := SCTPInitParameter(decodeSCTPParameter(paramData))
+ paramData = paramData[p.ActualLength:]
+ sc.Parameters = append(sc.Parameters, p)
+ }
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPInit) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ var payload []byte
+ for _, param := range sc.Parameters {
+ payload = append(payload, SCTPParameter(param).Bytes()...)
+ }
+ length := 20 + len(payload)
+ bytes, err := b.PrependBytes(roundUpToNearest4(length))
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], uint16(length))
+ binary.BigEndian.PutUint32(bytes[4:8], sc.InitiateTag)
+ binary.BigEndian.PutUint32(bytes[8:12], sc.AdvertisedReceiverWindowCredit)
+ binary.BigEndian.PutUint16(bytes[12:14], sc.OutboundStreams)
+ binary.BigEndian.PutUint16(bytes[14:16], sc.InboundStreams)
+ binary.BigEndian.PutUint32(bytes[16:20], sc.InitialTSN)
+ copy(bytes[20:], payload)
+ return nil
+}
+
+// SCTPSack is the SCTP Selective ACK chunk layer.
+type SCTPSack struct {
+ SCTPChunk
+ CumulativeTSNAck uint32
+ AdvertisedReceiverWindowCredit uint32
+ NumGapACKs, NumDuplicateTSNs uint16
+ GapACKs []uint16
+ DuplicateTSNs []uint32
+}
+
+// LayerType return LayerTypeSCTPSack
+func (sc *SCTPSack) LayerType() gopacket.LayerType {
+ return LayerTypeSCTPSack
+}
+
+func decodeSCTPSack(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPSack{
+ SCTPChunk: chunk,
+ CumulativeTSNAck: binary.BigEndian.Uint32(data[4:8]),
+ AdvertisedReceiverWindowCredit: binary.BigEndian.Uint32(data[8:12]),
+ NumGapACKs: binary.BigEndian.Uint16(data[12:14]),
+ NumDuplicateTSNs: binary.BigEndian.Uint16(data[14:16]),
+ }
+ // We maximize gapAcks and dupTSNs here so we're not allocating tons
+ // of memory based on a user-controlable field. Our maximums are not exact,
+ // but should give us sane defaults... we'll still hit slice boundaries and
+ // fail if the user-supplied values are too high (in the for loops below), but
+ // the amount of memory we'll have allocated because of that should be small
+ // (< sc.ActualLength)
+ gapAcks := sc.SCTPChunk.ActualLength / 2
+ dupTSNs := (sc.SCTPChunk.ActualLength - gapAcks*2) / 4
+ if gapAcks > int(sc.NumGapACKs) {
+ gapAcks = int(sc.NumGapACKs)
+ }
+ if dupTSNs > int(sc.NumDuplicateTSNs) {
+ dupTSNs = int(sc.NumDuplicateTSNs)
+ }
+ sc.GapACKs = make([]uint16, 0, gapAcks)
+ sc.DuplicateTSNs = make([]uint32, 0, dupTSNs)
+ bytesRemaining := data[16:]
+ for i := 0; i < int(sc.NumGapACKs); i++ {
+ sc.GapACKs = append(sc.GapACKs, binary.BigEndian.Uint16(bytesRemaining[:2]))
+ bytesRemaining = bytesRemaining[2:]
+ }
+ for i := 0; i < int(sc.NumDuplicateTSNs); i++ {
+ sc.DuplicateTSNs = append(sc.DuplicateTSNs, binary.BigEndian.Uint32(bytesRemaining[:4]))
+ bytesRemaining = bytesRemaining[4:]
+ }
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPSack) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ length := 16 + 2*len(sc.GapACKs) + 4*len(sc.DuplicateTSNs)
+ bytes, err := b.PrependBytes(roundUpToNearest4(length))
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], uint16(length))
+ binary.BigEndian.PutUint32(bytes[4:8], sc.CumulativeTSNAck)
+ binary.BigEndian.PutUint32(bytes[8:12], sc.AdvertisedReceiverWindowCredit)
+ binary.BigEndian.PutUint16(bytes[12:14], uint16(len(sc.GapACKs)))
+ binary.BigEndian.PutUint16(bytes[14:16], uint16(len(sc.DuplicateTSNs)))
+ for i, v := range sc.GapACKs {
+ binary.BigEndian.PutUint16(bytes[16+i*2:], v)
+ }
+ offset := 16 + 2*len(sc.GapACKs)
+ for i, v := range sc.DuplicateTSNs {
+ binary.BigEndian.PutUint32(bytes[offset+i*4:], v)
+ }
+ return nil
+}
+
+// SCTPHeartbeatParameter is the parameter type used by SCTP heartbeat and
+// heartbeat ack layers.
+type SCTPHeartbeatParameter SCTPParameter
+
+// SCTPHeartbeat is the SCTP heartbeat layer, also used for heatbeat ack.
+type SCTPHeartbeat struct {
+ SCTPChunk
+ Parameters []SCTPHeartbeatParameter
+}
+
+// LayerType returns gopacket.LayerTypeSCTPHeartbeat.
+func (sc *SCTPHeartbeat) LayerType() gopacket.LayerType {
+ if sc.Type == SCTPChunkTypeHeartbeatAck {
+ return LayerTypeSCTPHeartbeatAck
+ }
+ // sc.Type == SCTPChunkTypeHeartbeat
+ return LayerTypeSCTPHeartbeat
+}
+
+func decodeSCTPHeartbeat(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPHeartbeat{
+ SCTPChunk: chunk,
+ }
+ paramData := data[4:sc.Length]
+ for len(paramData) > 0 {
+ p := SCTPHeartbeatParameter(decodeSCTPParameter(paramData))
+ paramData = paramData[p.ActualLength:]
+ sc.Parameters = append(sc.Parameters, p)
+ }
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPHeartbeat) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ var payload []byte
+ for _, param := range sc.Parameters {
+ payload = append(payload, SCTPParameter(param).Bytes()...)
+ }
+ length := 4 + len(payload)
+
+ bytes, err := b.PrependBytes(roundUpToNearest4(length))
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], uint16(length))
+ copy(bytes[4:], payload)
+ return nil
+}
+
+// SCTPErrorParameter is the parameter type used by SCTP Abort and Error layers.
+type SCTPErrorParameter SCTPParameter
+
+// SCTPError is the SCTP error layer, also used for SCTP aborts.
+type SCTPError struct {
+ SCTPChunk
+ Parameters []SCTPErrorParameter
+}
+
+// LayerType returns LayerTypeSCTPAbort or LayerTypeSCTPError.
+func (sc *SCTPError) LayerType() gopacket.LayerType {
+ if sc.Type == SCTPChunkTypeAbort {
+ return LayerTypeSCTPAbort
+ }
+ // sc.Type == SCTPChunkTypeError
+ return LayerTypeSCTPError
+}
+
+func decodeSCTPError(data []byte, p gopacket.PacketBuilder) error {
+ // remarkably similar to decodeSCTPHeartbeat ;)
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPError{
+ SCTPChunk: chunk,
+ }
+ paramData := data[4:sc.Length]
+ for len(paramData) > 0 {
+ p := SCTPErrorParameter(decodeSCTPParameter(paramData))
+ paramData = paramData[p.ActualLength:]
+ sc.Parameters = append(sc.Parameters, p)
+ }
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPError) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ var payload []byte
+ for _, param := range sc.Parameters {
+ payload = append(payload, SCTPParameter(param).Bytes()...)
+ }
+ length := 4 + len(payload)
+
+ bytes, err := b.PrependBytes(roundUpToNearest4(length))
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], uint16(length))
+ copy(bytes[4:], payload)
+ return nil
+}
+
+// SCTPShutdown is the SCTP shutdown layer.
+type SCTPShutdown struct {
+ SCTPChunk
+ CumulativeTSNAck uint32
+}
+
+// LayerType returns gopacket.LayerTypeSCTPShutdown.
+func (sc *SCTPShutdown) LayerType() gopacket.LayerType { return LayerTypeSCTPShutdown }
+
+func decodeSCTPShutdown(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPShutdown{
+ SCTPChunk: chunk,
+ CumulativeTSNAck: binary.BigEndian.Uint32(data[4:8]),
+ }
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPShutdown) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ bytes, err := b.PrependBytes(8)
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], 8)
+ binary.BigEndian.PutUint32(bytes[4:8], sc.CumulativeTSNAck)
+ return nil
+}
+
+// SCTPShutdownAck is the SCTP shutdown layer.
+type SCTPShutdownAck struct {
+ SCTPChunk
+}
+
+// LayerType returns gopacket.LayerTypeSCTPShutdownAck.
+func (sc *SCTPShutdownAck) LayerType() gopacket.LayerType { return LayerTypeSCTPShutdownAck }
+
+func decodeSCTPShutdownAck(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPShutdownAck{
+ SCTPChunk: chunk,
+ }
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPShutdownAck) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ bytes, err := b.PrependBytes(4)
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], 4)
+ return nil
+}
+
+// SCTPCookieEcho is the SCTP Cookie Echo layer.
+type SCTPCookieEcho struct {
+ SCTPChunk
+ Cookie []byte
+}
+
+// LayerType returns gopacket.LayerTypeSCTPCookieEcho.
+func (sc *SCTPCookieEcho) LayerType() gopacket.LayerType { return LayerTypeSCTPCookieEcho }
+
+func decodeSCTPCookieEcho(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPCookieEcho{
+ SCTPChunk: chunk,
+ }
+ sc.Cookie = data[4:sc.Length]
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPCookieEcho) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ length := 4 + len(sc.Cookie)
+ bytes, err := b.PrependBytes(roundUpToNearest4(length))
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], uint16(length))
+ copy(bytes[4:], sc.Cookie)
+ return nil
+}
+
+// This struct is used by all empty SCTP chunks (currently CookieAck and
+// ShutdownComplete).
+type SCTPEmptyLayer struct {
+ SCTPChunk
+}
+
+// LayerType returns either gopacket.LayerTypeSCTPShutdownComplete or
+// LayerTypeSCTPCookieAck.
+func (sc *SCTPEmptyLayer) LayerType() gopacket.LayerType {
+ if sc.Type == SCTPChunkTypeShutdownComplete {
+ return LayerTypeSCTPShutdownComplete
+ }
+ // sc.Type == SCTPChunkTypeCookieAck
+ return LayerTypeSCTPCookieAck
+}
+
+func decodeSCTPEmptyLayer(data []byte, p gopacket.PacketBuilder) error {
+ chunk, err := decodeSCTPChunk(data)
+ if err != nil {
+ return err
+ }
+ sc := &SCTPEmptyLayer{
+ SCTPChunk: chunk,
+ }
+ p.AddLayer(sc)
+ return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
+}
+
+// SerializeTo is for gopacket.SerializableLayer.
+func (sc SCTPEmptyLayer) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ bytes, err := b.PrependBytes(4)
+ if err != nil {
+ return err
+ }
+ bytes[0] = uint8(sc.Type)
+ bytes[1] = sc.Flags
+ binary.BigEndian.PutUint16(bytes[2:4], 4)
+ return nil
+}
Code Review / govpp.git / blobdiff