[asterisk-dev] q931 decoding question

[Klaus Darilion]

Matthew Fredrickson schrieb:
> Klaus Darilion wrote:
          Ext: 0  User information layer 1: Unknown (24)
>>
>> My questions: Why does it gets parsed? Why is it set to 24? I checked 
>> libpri source code but could not find the relevant code. Maybe someone 
>> can point to the corresponding code.
> 
> This looks like a bug in the Q.931 dumping code.  After I looked into 
> it, I saw that an oversight was made in the bearer_capability_dump 
> routine that is assume a length that doesn't include the IE name and 
> length in the length passed to it.  The bug was not present in the 
> bearer_capability_transmit routine, but on the off chance there might be 
> something like this elsewhere, I saw something similar in the _receive 
> routine and fixed it as well.  The bug in the receive routine appears to 
> be benign because of the way we're using it in Asterisk.  Please update 
> to latest 1.2, 1.4, or trunk from svn to see if it is fixed now.
> 

Ok. So how is it handled now if UL1 it is not present?

Do you know if there is a difference in Q.931 between missing octets and 
values set to zero? E.g. is there a difference between UL1 set to zero 
or a missing UL1 octet?

Btw - there is also a new patch on mantis for proper decoding:
http://bugs.digium.com/view.php?id=11593


regards
klaus