diff options
Diffstat (limited to 'vendor/github.com/google/gopacket/layers/sctp.go')
-rw-r--r-- | vendor/github.com/google/gopacket/layers/sctp.go | 746 |
1 files changed, 0 insertions, 746 deletions
diff --git a/vendor/github.com/google/gopacket/layers/sctp.go b/vendor/github.com/google/gopacket/layers/sctp.go deleted file mode 100644 index 511176e..0000000 --- a/vendor/github.com/google/gopacket/layers/sctp.go +++ /dev/null @@ -1,746 +0,0 @@ -// 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 -} |