[tor-bugs] #11050 [Obfsproxy]: pycrypto's AES implementation is not constant time

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#11050: pycrypto's AES implementation is not constant time
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 Reporter:  yawning                      |          Owner:  asn
     Type:  defect                       |         Status:  new
 Priority:  normal                       |      Milestone:
Component:  Obfsproxy                    |        Version:
 Keywords:  AES, cache timing, pycrypto  |  Actual Points:
Parent ID:                               |         Points:
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 This is a non-issue when AES-NI is supported by the host CPU since a
 separate code path is taken.

 https://github.com/dlitz/pycrypto/blob/master/src/AES.c

 It's not too bad in the pluggable transport case since traffic is super-
 enciphered, the session keys are ephemeral, and actually extracting
 sufficiently accurate timing information is probably non-trivial, but it
 probably should be addressed somehow.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/11050>
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