[tor-bugs] #3443 [Tor Client]: Client with low CBT can't switch to a bridge if it's slow

Mon Apr 23 05:48:07 UTC 2012

#3443: Client with low CBT can't switch to a bridge if it's slow
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 Reporter:  arma        |          Owner:                    
     Type:  defect      |         Status:  new               
 Priority:  major       |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Client  |        Version:                    
 Keywords:  regression  |         Parent:                    
   Points:              |   Actualpoints:                    
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Comment(by mikeperry):

 The CBT function is called circuit_build_times_network_check_changed().
 Upon reviewing it, the comments tell me that it only counts circuits that
 complete a first hop against the timeout. The source seems to be
 consistent with the comments.

 If your bridge was so slow the first hop didn't ever complete (which the
 logs seem to say happened at least once), that could be a problem.

 We used to have a lot more cases to handle first hop failures along with
 general network disconnect, but we decided to simplify it, because the
 edge cases were a nightmare.

 If we want to do a hack to abandon CBT if all guards change, it seems like
 circuit_build_times_network_check_changed() would be an OK place to add
 such a check.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3443#comment:8>
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