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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/2222/">https://reviewboard.asterisk.org/r/2222/</a>
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<p style="margin-top: 0;">On December 4th, 2012, 5:21 p.m., <b>Mark Michelson</b> wrote:</p>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">First off, the changes you have regarding the use of a named constant instead of magic numbers are great, as is the change you made regarding the setting of the cached Min-SE.
The other parts seem off.
The test you have created is not valid. If Asterisk is set to "accept" mode, then it should not be putting any sort of session-timers headers in the initial INVITE. If it's not sending any session-timer headers in the INVITE, then it doesn't make sense that the endpoint would respond with a 422 since there was no proposed session interval. If we do go up against an endpoint that sends us a 422 when we haven't proposed session timers, then I'm really not sure how we should react to that, to be honest. Since they should be proposing a Min-SE in their 422, we could potentially respond with some sort of Session Timer proposal, but that would violate the local policy of what "accept" means. I think that if we receive a 422 when we're in "accept" mode, then we're clearly dealing with a broken implementation and should not attempt to renegotiate.
The change you have put in now can result in placing a Min-SE header but no Session-Expires header in the initial INVITE when in "accept" mode, which is less than ideal.
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<p>On December 5th, 2012, 8:45 a.m., <b>opticron</b> wrote:</p>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">When in "accept" mode, Asterisk offers "timer" in the Supported header. This allows intermediate proxies to place a Session-Expires header in the invite or to reduce the value thereof according to RFC 4028. Later proxies or the final recipient of the message can then respond with a 422 specifying a Min-SE header which Asterisk will be required to include in all further attempts.
I agree that Asterisk should not be placing a Min-SE or Session-Expires in the initial invite when in "accept" mode. The test for including that needs a little tweaking.</pre>
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<p>On December 5th, 2012, 9:25 a.m., <b>opticron</b> wrote:</p>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Actually, including a Min-SE in the initial invite when in "accept" mode could prevent the situation where we receive a 200 OK with an unacceptably low Session-Expires (according to peer configuration) and need to tear down the call after the fact (which doesn't currently happen, see ASTERISK-20653). The end result would be acceptance of a call that does not conform to the configuration of the peer. If/When ASTERISK-20653 gets fixed, this situation becomes less of an issue since the call can be torn down as expected.</pre>
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<p>On December 12th, 2012, 10:27 a.m., <b>Mark Michelson</b> wrote:</p>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Okay, this makes sense. Having a Min-SE present with no proposed Session-Expires gives a "hint" to proxies and UAs in the path what they should propose as the Session-Expires as well.
The one thing I'm not sure of is if Asterisk, as a UAS, will handle this correctly. Do we inspect Min-SE if there is no Session-Expires present? It doesn't appear that we do. We should open an issue to make sure we change Asterisk's UAS behavior to search for a Min-SE header even if Session-Expires is not present.</pre>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Issue created: https://issues.asterisk.org/jira/browse/ASTERISK-20787</pre>
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<p>- Mark</p>
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<p>On November 30th, 2012, 4:26 p.m., opticron wrote:</p>
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<div>Review request for Asterisk Developers.</div>
<div>By opticron.</div>
<p style="color: grey;"><i>Updated Nov. 30, 2012, 4:26 p.m.</i></p>
<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">RFC 4028 states that if a 422 response is ever received during a session refresh or during a call attempt (and the UAC wishes to retry), the all subsequent attempts or refreshes must have a Min-SE header. Asterisk does not currently do this if operating in the "accept" mode. This patch corrects this behavior and swaps out a few magic numbers for a pre-existing constant.
This was discovered when writing the test for https://reviewboard.asterisk.org/r/2223/</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Before this patch, the test in https://reviewboard.asterisk.org/r/2223/ failed. After the patch, it passes.</pre>
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<b style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Bugs: </b>
<a href="https://issues.asterisk.org/jira/browse/SWP-5051">SWP-5051</a>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>branches/1.8/channels/chan_sip.c <span style="color: grey">(376948)</span></li>
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<p><a href="https://reviewboard.asterisk.org/r/2222/diff/" style="margin-left: 3em;">View Diff</a></p>
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