[tor-bugs] #11100 [Obfsproxy]: ScrambleSuit session ticket handshake failures

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#11100: ScrambleSuit session ticket handshake failures
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     Reporter:  yawning    |      Owner:  phw
         Type:  defect     |     Status:  needs_review
     Priority:  normal     |  Milestone:
    Component:  Obfsproxy  |    Version:
   Resolution:             |   Keywords:  ScrambleSuit, SessionTicket
Actual Points:             |  Parent ID:
       Points:             |
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Changes (by yawning):

 * status:  new => needs_review


Comment:

 Ok, that's why this happens.  The key creation date isn't actually getting
 updated so any bridge currently that hits the regeneration interval will
 rotate the Session Ticket keys on every single attempted handshake.

 I was failing to reproduce this locally since my test bridge was never
 running for long enough to trigger this case.

 This along with #11092 justifies a mandatory update of every single
 ScrambleSuit bridge out there, because "the first Session Ticket Handshake
 will fail after 5 mins" if the bridge has an uptime > 1 week is
 unacceptable.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/11100#comment:2>
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