In one SCTP package we can have multiple SCTPData chunks. The current code doesn't support it and will provide all other chunks as payload. I removed the special case of decodeSCTPChunk and then put a Payload into the SCTPData struct. One issue is that the test data is kind of invalid...

The fundamental issue is that the structure of SCTP is like this.

   IP
  SCTP
  SCTPDataChunk
     Payload
  SCTPDataChunk
     Payload

While p.NextDecoder will just be linear. We would need to have some kind of special "Payload" so we can jump to the next SCTPDataChunk. Alternatively be always eager for SCTP...