[tor-bugs] #7707 [Tor]: Impose a minimum write size for TLS writes

Mon Sep 30 15:40:15 UTC 2013

#7707: Impose a minimum write size for TLS writes
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     Reporter:  nickm    |      Owner:
         Type:  defect   |     Status:  needs_information
     Priority:  normal   |  Milestone:  Tor: 0.2.5.x-final
    Component:  Tor      |    Version:
   Resolution:           |   Keywords:  tor-relay performance bwbug
Actual Points:           |  024-backport
       Points:           |  Parent ID:
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Comment (by nickm):

 Hm. Assuming recent TLS versions (to ignore the empty record trick for
 now), we're looking at a 20 byte MAC, a 16 byte IV, 1-16 bytes  of
 padding, and 5-10 bytes of headers if I'm reading this format right.  That
 comes to something like 40-50 bytes of overhead per record, which makes it
 non-crazy to have ~10% overhead.

 Somebody else should check my math and spec-fu.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7707#comment:16>
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