[tor-bugs] #14937 [Tor Browser]: Get meek working in Tor Circuit Display

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#14937: Get meek working in Tor Circuit Display
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     Reporter:            |      Owner:  tbb-team
  arthuredelstein         |     Status:  needs_information
         Type:  defect    |  Milestone:
     Priority:  normal    |    Version:
    Component:  Tor       |   Keywords:  tbb-circuit-display, tbb-usability
  Browser                 |  Parent ID:
   Resolution:            |
Actual Points:            |
       Points:            |
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Comment (by dcf):

 Replying to [comment:9 arthuredelstein]:
 > As I mentioned, I think #13882 fixed this problem for most pluggable
 transports, including obfs3. To test it, you'll need to build the master
 branch of torbutton.git and install the xpi into Tor Browser. I just
 tested bridges from https://bridges.torproject.org/bridges?transport=obfs3
 and I get, for example "Sweden (Bridge: obfs3)". Most transports,
 including obfs3, have the IP address and fingerprint in the bridge conf
 line, so I'm just using that (in the latest patch). So my question is how
 to identify an entry-node fingerprint as a meek node, given that I don't
 have a fingerprint and IP from the bridge conf. Somehow, the meek code
 must be converting url/front into a fingerprint, correct?

 It's tor that learns the fingerprint (and true IP) when it connects to the
 bridge. meek-client is pretty ignorant of the Tor protocol flowing through
 it. The url/front is just used to set up the "transport layer" that Tor
 uses to connect to the bridge. Once tor has a channel to the bridge, it
 finds out the IP and fingerprint somehow. (NETINFO cell maybe? I dunno.)

 So what you do is get the fingerprint from the control port, then find a
 bridge line with a matching fingerprint, and peek at the transport name in
 the bridge line? And it doesn't work for the meek bridge lines because
 they don't have a fingerprint?

 I don't know a good way to solve it. Maybe what armadev said in comment:7.
 It seems like the control port ought to know what transport you are using.

 Maybe as a special-case workaround, you can say, if there's only one
 bridge line configured, then you can match it even if it doesn't have a
 fingerprint.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/14937#comment:10>
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