[tor-bugs] #9635 [Tor]: Tor clients warn when they use the wrong ntor onion key

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#9635: Tor clients warn when they use the wrong ntor onion key
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     Reporter:  bastik  |      Owner:
         Type:  defect  |     Status:  new
     Priority:  normal  |  Milestone:  Tor: 0.2.5.x-final
    Component:  Tor     |    Version:  Tor: unspecified
   Resolution:          |   Keywords:  tor-bridge 024-backport
Actual Points:          |  Parent ID:
       Points:          |
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Comment (by nickm):

 rransom is correct that there ''is'' a perfectly good way (KEYID) for the
 relay to learn which ntor key was supposed to get used.

 But, if  for some weird reason, the client has an onion key so ancient
 that the relay doesn't recognize it any longer, then rather than send a
 DESTROY cell, the relay will pick a junk onion key and use that to
 complete the handshake anyway, on the theory that it's better not to leak
 ''anything'' in timing information.  Could that be what's going on here?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/9635#comment:6>
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