[tor-bugs] #30716 [Circumvention/Obfs4]: Improve the obfs4 obfuscation protocol

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#30716: Improve the obfs4 obfuscation protocol
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 Reporter:  phw                                 |          Owner:  phw
     Type:  task                                |         Status:  assigned
 Priority:  High                                |      Milestone:
Component:  Circumvention/Obfs4                 |        Version:
 Severity:  Normal                              |     Resolution:
 Keywords:  sponsor28, anti-censorship-roadmap  |  Actual Points:
Parent ID:                                      |         Points:  20
 Reviewer:                                      |        Sponsor:
                                                |  Sponsor28-must
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Comment (by yawning):

 The framing could use better cryptography and a more sensible design
 overall, but there are larger deficiencies in the protocol.

 > So one desideratum from me is that the protocol should allow either side
 to send any amount of data at any time, and have it correctly interpreted
 as padding or meaningful data. Ideally it should even be possible for the
 server to send data before the client has sent anything.

 At one point I had thoughts of how I would like to implement something
 like this, but it's been years since I gave serious thought about this
 problem.  I personally would have felt uneasy about a responder-speaks-
 first design.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/30716#comment:3>
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