[tor-bugs] #7341 [Tor]: circuit_expire_building applies CBT in twisted ways on hidden service circuits

[Tor Bug Tracker & Wiki]

#7341: circuit_expire_building applies CBT in twisted ways on hidden service
circuits
-----------------------+----------------------------------------------------
 Reporter:  mikeperry  |          Owner:     
     Type:  defect     |         Status:  new
 Priority:  normal     |      Milestone:     
Component:  Tor        |        Version:     
 Keywords:             |         Parent:     
   Points:             |   Actualpoints:     
-----------------------+----------------------------------------------------

Comment(by rransom):

 Replying to [comment:3 mikeperry]:
 > Replying to [comment:2 mikeperry]:
 > > I am tempted to simply remove the has_opened -> cannibalized timeout
 differentiation, and simply use the desired_path_len for cutoff selection.
 >
 > Wow, after running this fix for just a few minutes, and I'm now seeing
 desired_path_len's of 5 for purpose 6. Is that a different bug, or do we
 also need a fivehop_cutoff for hidden services circuits for some reason?

 This means that those client-side intro circuits reached the introduction
 point, sent an INTRODUCE1 cell, and then decided that they should re-
 introduce to the HS at some other intro point (I ''suspect'' that means
 the client's `_C_REND_READY` or `_C_REND_READY_INTRO_ACKED` circuit timed
 out, but I haven't looked at that code in a while, and it's a mess).

 #1297 might be worth reading if you haven't found it already.

 > I'm going to let this run for a few hours and see what the final counts
 look like.
 >
 > Meanwhile, if anyone knows why hidden service client circuits with a
 purpose of CIRCUIT_PURPOSE_C_INTRODUCING would have a desired_path_len of
 5 in normal operation, that would be useful info.

 https://gitweb.torproject.org/tor.git/blob/tor-0.2.4.6-alpha:/src/or/rendclient.c#l91

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7341#comment:4>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online