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<div class="moz-cite-prefix">El 05/09/13 03:57, Olle E. Johansson
escribió:<br>
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cite="mid:73624C63-C171-4D11-A264-BC65A2784610@edvina.net"
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<a moz-do-not-send="true"
href="https://issues.asterisk.org/jira/browse/ASTERISK-17899">https://issues.asterisk.org/jira/browse/ASTERISK-17899</a>
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<div apple-content-edited="true"><span class="Apple-style-span"
style="border-collapse: separate; font-size: 12px;
border-spacing: 0px; ">
<div>I've done a lot of research about this and find a
worrysome amount of pages where people explain that this
is a bug in Asterisk and a few different patches floating
around. That's not a good situation. It does break
communication in a customer platform I'm working with.</div>
<div><br>
</div>
<div>The story is this:</div>
<div><br>
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<div>In SDES we send master crypto keys in clear text (don't
laugh, please). The keys can have attributes for the
lifetime - number of packets we can use this key for - and
a master key index. In asterisk, if someone sends us this
attribute which quite a lot of servers and phones seems to
do, we break the call and do not accept - even if the
lifetime is 2^31 packets which is quite a long call,
spanning decades, with a rate of 50 packets per second.</div>
<div><br>
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<div>We do not have to answer with any attributes on our
key. The key attributes are just declarative, not an
offer/answer item.</div>
<div><br>
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</span>
<div style="font-size: 12px; ">I consider this a bug that we
need to fix in all release versions. There's a correct way
of solving it - using packet counters and forcing a
re-invite and a key reset beforehand or a quick and dirty
where we accept all lifetimes above a treshold, like 2^20
and assume no calls will be that long or that if they are,
the other end will start a key reset.</div>
<div style="font-size: 12px; "><br>
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</div>
My questions to the esteemed reader of this list:</div>
<div>- can we agree that the current behaviour is a bug?</div>
<div>- which solution should we code for?</div>
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</blockquote>
If I understand correctly, the SRTP lifetime is the same issue
covered in <a class="moz-txt-link-freetext" href="https://issues.asterisk.org/jira/browse/ASTERISK-20233">https://issues.asterisk.org/jira/browse/ASTERISK-20233</a> ,
and that bug was closed as "Not A Bug", since this was a "feature
request" and therefore better discussed in the mailing list.<br>
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