> On 30. Jul 2018, at 21:03, Harald Welte <[email protected]> wrote:
>
> Hi Holger,
>
Hey!
> I think the solution to the problem is that your test case parses the
> IDENTITY REQUESET format, which has 8bit length fields, while the function
> is normally (without the offset) used for the IDENTITY RESPONSE packets, where
> there are 16bit length fields.
nothing genius in the end just poking in the blind trying to understand a
binary protocol and getting it wrong... When looking at the traces I wondered
if they got \0 termination of strings wrong and didn't consider that
request/response would use different length fields. But 16bit length fields
seem to make sense.
Nice find! We can clean this up in the osmo-bts code as well.
> I'll look into this once I find time and make sure we have test cases for
> both,
> as well as fix the bug about the extraneous byte that my patch
> https://gerrit.osmocom.org/#/c/libosmocore/+/10216/ attempts to fix - and
> which
> is required to make external USSD entities in osmo-hlr work.
It looks like we can throw away the entire ipa_ccm_idtag_parse_off and time to
create a TLV_TYPE_L16TV?
holger
