[tor-bugs] #10893 [Pluggable transport]: ScrambleSuit spec improvements

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#10893: ScrambleSuit spec improvements
-------------------------------------+-------------------------------
     Reporter:  yawning              |      Owner:  phw
         Type:  defect               |     Status:  new
     Priority:  normal               |  Milestone:
    Component:  Pluggable transport  |    Version:
   Resolution:                       |   Keywords:  scramblesuit spec
Actual Points:                       |  Parent ID:
       Points:                       |
-------------------------------------+-------------------------------

Comment (by yawning):

 Another one.

  * k_t used for the Session Ticket handshake HMACs is the result of 2.3
 Key Derivation, instead of being the raw k_t.  The obfsproxy
 implementation is incorrect, but it's deployed so it wins, at least as far
 as what goes into obfsclient.

 {{{
             log.debug("Redeeming stored session ticket.")
             (masterKey, rawTicket) = storedTicket
             self.deriveSecrets(masterKey)
 self.circuit.downstream.write(ticket.createTicketMessage(rawTicket,
 self.sendHMAC))
 }}}

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10893#comment:2>
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