20 Jan
2017
20 Jan
'17
7:38 p.m.
On 19/01/2017 22:56, Daniel-Constantin Mierla wrote:
Hello,
On 19/01/2017 10:48, Hai Bui Duc Ha wrote:
The problem is the value of Content-Lenght set by the client -- it is
set only to the size that it is view as part of the invite. A bit later
the client sends more sdp, but exceeding the size sent in C-L header.
That part of SDP remains as garbage.
So there is a bug in client app.
Cheers,
Daniel
--
Daniel-Constantin Mierla
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio World Conference - May 8-10, 2017 - www.kamailioworld.com
Hi Daniel,
Thank you for reply.
On Tue, Jan 17, 2017 at 6:05 PM, Daniel-Constantin Mierla
<miconda(a)gmail.com <mailto:miconda@gmail.com>> wrote:
Hello,
apparently I missed the follow ups on this discussion, dragged in
by other topics on mailing list.
Can you get the pcap with all the traffic taken on kamailio
server for the call (from initial invite to the end of the call)?
I send you the pcap at enclosed file. You can see the packet *No.5 *,
it missing SIP message body:
/* Media Attribute (a): rtpmap:8 PCMA/8000*/
/* Media Attribute (a): rtpmap:101 telephone-event/8000*/
/* Media Attribute (a): fmtp:101 0-16*/
I expect that content length is mismatching or there is a '\0'
inside the sdp.
Can you explain me more about this ?
TCP is a stream protocol, meaning that the
application (kamailio) need
to read and parse to figure out the end of a SIP message. The state
machine as per RFC requires the application to read and identify the
Content-Length header, take its value, read until the end of headers
is found (an empty line) and from there on read as much as the value
of Content-Length to get the body and consider the end of message there.
If the sending application puts a lower value in the Content-Length
than the number of chars in the body, the rest remains in the buffer
and the receiving application (kamailio) attempts to parse a new SIP
message.
The other thing I was thinking of was the presence of '\0' which marks
the end of string in C.
I will look at the pcap very soon and see what I find there.