[h323plus] crash when SessionID=0

Igor Pavlov pavlov.ig at gmail.com
Wed Aug 18 10:38:43 EDT 2010


Now, I have no available MXP for tests :( but when I had it I found out the
way to open extended video channel :
1. Send Generic request
2. Wait for Generic response
3. Send Generic Indication
4. Send OLC(extended video channel) with sessionID = 0 (!)
5. Send miscellatiousIndication LogicalChannelActive

18 августа 2010 г. 18:17 пользователь Marek Domaracky <domarack at cern.ch>написал:

>  Hi Igor,
>
> I'm testing as well with MXP and in my case MXP sending always 33 and
> higher. So far I had a problem only with the Mirial.
> What I have so far is just one way channel from the device to my
> application. Are you opening extended video form your application to the
> MXP?
> If I understand correctly if you send OLC with sessionID != 0 Tandberg will
> reject?
> Thanks,
>
> Marek
>
>
>
>
> On 08/18/2010 03:42 PM, Igor Pavlov wrote:
>
> I wnat to enlarge...
> When Tandberg (MXP) sends extended video channel, it sends sessionID=0, and
> only in OLCAck it accept actual sessionID.
> If send OLC for extended video with sessionID != 0 than Tandberg MXP sends
> OLCReject (InvalidSessionID).
>
> 2010/8/18 Marek Domaracky <domarack at cern.ch>
>
>> Hi,
>>
>> I'm working on H.239 implementation and find out that devices might ask
>> SessionID=0 for a new video channel. In particular I did a test with Mirial.
>> I was checking the  thread
>> http://lists.packetizer.com/pipermail/h323plus/2009-December/001269.htmland it's mentioned that the SessionID=0 is invalid.
>> I know it's not following the standard as for RTPSession  the range is
>> from 1..255, but for compatibility, don't you think we should allow it? I
>> did a test call from Mirial to Tandberg and Tandberg didn't have a problem
>> with it.
>> The lines involved are
>> rtp.cxx
>> from  PAssert(id > 0 && id < 256, PInvalidParameter); to PAssert(id >= 0
>> && id < 256, PInvalidParameter);
>> and
>> h323.cxx
>>  // We must have a valid sessionID
>>  if (sessionID < 1 || sessionID > 255) to if (sessionID < 0 || sessionID >
>> 255)
>>
>> Thanks,
>>
>> Marek
>>
>>
>>
>>
>
>
> --
> Игорь Павлов
>
>


-- 
Игорь Павлов
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.packetizer.com/pipermail/h323plus/attachments/20100818/1104ff98/attachment-0003.html>


More information about the h323plus mailing list