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<p>Hello,<br>
</p>
<br>
<div class="moz-cite-prefix">On 19/01/2017 10:48, Hai Bui Duc Ha
wrote:<br>
</div>
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cite="mid:CA+Gtc=TjJwoWLOt2A4t8Sx2R5EZUhjr12sC15ryX381dq9=r8w@mail.gmail.com"
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<div>Hi Daniel,<br>
<br>
</div>
Thank you for reply.<br>
</div>
<br>
<div class="gmail_extra">
<div class="gmail_quote">On Tue, Jan 17, 2017 at 6:05 PM,
Daniel-Constantin Mierla <span dir="ltr"><<a
moz-do-not-send="true" href="mailto:miconda@gmail.com"
target="_blank">miconda@gmail.com</a>></span> wrote:<br>
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<p>Hello,</p>
<p>apparently I missed the follow ups on this
discussion, dragged in by other topics on mailing
list. <br>
</p>
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<p>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)?</p>
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</blockquote>
<div>I send you the pcap at enclosed file. You can see the
packet <b>No.5 </b>, it missing SIP message body:<br>
<i><b> Media Attribute (a): rtpmap:8 PCMA/8000</b></i>
<div><i><b> Media Attribute (a): rtpmap:101
telephone-event/8000</b></i></div>
<div><i><b> Media Attribute (a): fmtp:101 0-16</b></i></div>
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<p> I expect that content length is mismatching or there
is a '\0' inside the sdp.</p>
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<div>Can you explain me more about this ? <br>
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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.<br>
<br>
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.<br>
<br>
The other thing I was thinking of was the presence of '\0' which
marks the end of string in C.<br>
<br>
I will look at the pcap very soon and see what I find there.<br>
<br>
Cheers,<br>
Daniel<br>
<pre class="moz-signature" cols="72">--
Daniel-Constantin Mierla
<a class="moz-txt-link-abbreviated" href="http://www.twitter.com/miconda">www.twitter.com/miconda</a> -- <a class="moz-txt-link-abbreviated" href="http://www.linkedin.com/in/miconda">www.linkedin.com/in/miconda</a>
Kamailio World Conference - May 8-10, 2017 - <a class="moz-txt-link-abbreviated" href="http://www.kamailioworld.com">www.kamailioworld.com</a></pre>
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