[tor-bugs] #2511 [Tor Client]: Tor will use an unconfigured bridge if it was a configured bridge last time you ran Tor

[Tor Bug Tracker & Wiki]

#2511: Tor will use an unconfigured bridge if it was a configured bridge last time
you ran Tor
------------------------+---------------------------------------------------
 Reporter:  arma        |       Owner:                    
     Type:  defect      |      Status:  new               
 Priority:  normal      |   Milestone:  Tor: 0.2.2.x-final
Component:  Tor Client  |     Version:                    
 Keywords:              |      Points:                    
   Parent:              |  
------------------------+---------------------------------------------------

Comment(by arma):

 Option 1 to fix it is to change entry_guard_set_status() so it sets you as
 Down if you're not a configured bridge, even if we have a descriptor and
 it's purpose bridge. But that fix is going to produce peripheral bugs, for
 example where we fetch the new descriptor but then discard it (see #2510
 for an example scenario where that can happen in practice).

 Option 2 to fix it is to drop the descriptor when we read it, if it's a
 bridge descriptor that isn't a currently configured bridge. Then that
 entry guard will get marked down (reason "unlisted"), and it won't get
 used until we get a fresh descriptor (which presumably we'd only get by
 receiving it in response to a /tor/server/authority request to one of our
 configured bridges).

 Option 3 is to drop bridge descriptors for unconfigured bridges and also
 nuke their stanza from the entry guard list. That would force them to get
 readded to the entry guard list (once we get a fresh descriptor) if we
 want to, and would reduce other weird side-effect bugs.

 Currently I think option 2 should be sufficient.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2511#comment:2>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online