func decodeSCTPData(data []byte, p gopacket.PacketBuilder) error {
sc := &SCTPData{
SCTPChunk: decodeSCTPChunk(data),
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: binary.BigEndian.Uint32(data[12:16]),
}
// Length is the length in bytes of the data, INCLUDING the 16-byte header.
sc.PayloadData = data[16:sc.Length]
p.AddLayer(sc)
p.SetApplicationLayer(sc)
return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
}
// decodeEthernetCTPFromFunctionType reads in the first 2 bytes to determine the EthernetCTP
// layer type to decode next, then decodes based on that.
func decodeEthernetCTPFromFunctionType(data []byte, p gopacket.PacketBuilder) error {
function := EthernetCTPFunction(binary.LittleEndian.Uint16(data[:2]))
switch function {
case EthernetCTPFunctionReply:
reply := &EthernetCTPReply{
Function: function,
ReceiptNumber: binary.LittleEndian.Uint16(data[2:4]),
Data: data[4:],
BaseLayer: BaseLayer{data, nil},
}
p.AddLayer(reply)
p.SetApplicationLayer(reply)
return nil
case EthernetCTPFunctionForwardData:
forward := &EthernetCTPForwardData{
Function: function,
ForwardAddress: data[2:8],
BaseLayer: BaseLayer{data[:8], data[8:]},
}
p.AddLayer(forward)
return p.NextDecoder(gopacket.DecodeFunc(decodeEthernetCTPFromFunctionType))
}
return fmt.Errorf("Unknown EthernetCTP function type %v", function)
}