[tor-bugs] #11119 [Tor]: Write a proposal for client-side key pinning

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#11119: Write a proposal for client-side key pinning
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     Reporter:  nickm    |      Owner:
         Type:  defect   |     Status:  needs_information
     Priority:  normal   |  Milestone:  Tor: 0.2.6.x-final
    Component:  Tor      |    Version:
   Resolution:           |   Keywords:  tor-client needs-proposal
Actual Points:           |  026-triaged-1
       Points:           |  Parent ID:
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Changes (by nickm):

 * status:  new => needs_information


Comment:

 I started writing up a proposal draft here, but I'm not currently seeing
 the point of it.  If a client has a correct consensus, it should get the
 correct RSA1024<->Ed25519 mappings unless the authorities are lying.  But
 if the authorities are lying, they can poison the clients in lots of other
 ways too.

 Similarly, for stuff like bridges, we can export the ed25519 key in the
 bridge line, and we don't need to remember the RSA1024 key at all.  That's
 probably a better idea than pinning in the first place, right?

 For guards, we should remember every public key we've seen for the guard,
 and only connect if all the keys are good.

 So, what's the value here?  What's the threat model it helps for?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/11119#comment:2>
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