Issue

A defintion of SEQUENCESIZE(1..128, ...) can not be decoded/encoded (see CPM v2.1.1)[https://github.com/virtual-vehicle/vehicle_captain_its_asn1_specifications/blob/master/experimental/CPM-PDU-Descriptions.asn].

Setup

Generator: https://github.com/brchiu/asn1c.git (velichkov_s1ap_plus_option_group_plus_adding_trailing_ull)

Problem Description

Encoding of such a datatype leads into a bitshift of one to the left of the first decoded value after the start of the sequence (when compared to Wireshark as reference decoder).

Decoding of a valid CPM results into a bitshift to the right of the first decoded value after the start of the sequence (when compared to Wireshark as reference decoder).

Likely Cause

The additional "..." seems to be important and needs to be respected by the decoder/encoder. But this seems not be implemented into the Generator

Unsuccessful Workarounds

removing the "..." in the asn1 definition will not fix the problem. The newly generated code is exactly the same. Hence this issue is most likely part of the core components of the generator.

Possible Solutions

none

Status

If you want to use specifications of that type, we suggest to use another Generator for the messages. Thank you though for trying to opt for this FOSS!

virtual-vehicle / vehicle_captain_its_lib_c_cxx

SEQUENCESIZE(1..128, ...) creates invalid decoder/encoder #3