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<p class="MsoNormal">Thanks Steve --- That is much clearer. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Ultimately my concern is the possibility of a midstream pickup causing the src and dst hosts to be reversed even with the async set to true. IIRC I am pretty sure that the docs indicate that once the directionality for any pair of hosts
is set, it doesn’t get changed for an indefinite period of time. <o:p></o:p></p>
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<p class="MsoNormal">Sean<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> Steve Castellarin [mailto:steve.castellarin@gmail.com]
<br>
<b>Sent:</b> Wednesday, February 07, 2018 12:37 PM<br>
<b>To:</b> Cloherty, Sean E <scloherty@mitre.org><br>
<b>Cc:</b> oisf-users@lists.openinfosecfoundation.org<br>
<b>Subject:</b> Re: [Oisf-users] Question "don’t allow midstream session pickups"<o:p></o:p></p>
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<p class="MsoNormal">Hey Sean,<o:p></o:p></p>
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<p class="MsoNormal"><br>
Take a look at <a href="http://suricata.readthedocs.io/en/latest/configuration/suricata-yaml.html">http://suricata.readthedocs.io/en/latest/configuration/suricata-yaml.html</a>, section 8.1.12.3 (Stream-engine). There's a much better explanation than that
in the comments of the YAML. As for "midstream: true" I think it means Suricata will not ignore streams that were created before Suricata started. I'm not sure about "async-onside: true/false".<o:p></o:p></p>
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<p class="MsoNormal"><br>
Steve<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, Feb 7, 2018 at 12:26 PM, Cloherty, Sean E <<a href="mailto:scloherty@mitre.org" target="_blank">scloherty@mitre.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I’ve got a question about something that has made me wonder for a while –<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Does midstream: false “#don’t allow midstream session pickups” mean that it is not being allowed or is it that “don’t allow midstream” is not allowing midstream pickup if the
value is true? <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I am assuming that the true or false indicates that the function is enabled or disabled. However, reading the setting value and the remark following … the double negative “false
and “don’t allow” leaves me wondering.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I have the same question for async-oneside: false.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">midstream: false # don't allow midstream session pickups<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">async-oneside: false # don't enable async stream handling<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Sean Cloherty<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">InfoSec Engineer/Scientist, Lead<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:MITRE;color:#2E74B5">MITRE</span> Corporation<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">office
<a href="tel:(781)%20271-3707" target="_blank">(781) 271-3707</a><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">cell
<a href="tel:(781)%20697-8043" target="_blank">(781) 697-8043</a><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal"><br>
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