code: func nakedDecode(src []byte, t Type) (int, error) {
  	// decode header
  	hl, _, rl, err := headerDecode(src, t)
  
  	// check remaining length
  	if rl != 0 {
  		return hl, makeError(t, "expected zero remaining length")
  	}
  
  	return hl, err
  }
docs: // decodes a naked packet