[tor-bugs] #10418 [Tor Launcher]: Make a "Use Default Bridges" Radio button in the Tor Launcher Bridge UI

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#10418: Make a "Use Default Bridges" Radio button in the Tor Launcher Bridge UI
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     Reporter:  mikeperry     |      Owner:  brade
         Type:  enhancement   |     Status:  new
     Priority:  major         |  Milestone:
    Component:  Tor Launcher  |    Version:
   Resolution:                |   Keywords:
Actual Points:                |  Parent ID:
       Points:                |
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Comment (by dcf):

 Replying to [comment:3 brade]:
 > I don't think it will be too difficult to add radio buttons to allow use
 of a default set of bridges.  Will the other non-bridge configuration
 options be pre-configured in torrc-defaults?  Or will Tor Launcher need to
 configure other parameters?

 From my point of view, it would be great for the button to effectively
 uncomment the commented lines in https://gitweb.torproject.org/user/dcf
 /tor-browser-bundle.git/blob/901eab38b929ba1f3784437f2a16ca94aa7fc22e
 :/Bundle-Data/linux/Data/Tor/torrc-defaults. That is, the `Bridge` lines,
 `LearnCircuitBuildTimeout`, and `CircuitBuildTimeout`. We already have the
 `ClientTransportPlugin` lines uncommented because we have
 [https://gitweb.torproject.org/user/dcf/tor-browser-
 bundle.git/blob/901eab38b929ba1f3784437f2a16ca94aa7fc22e:/gitian/patches/bug5018.patch
 a patch] for #5018.

 If you want to separate the transports, separate buttons for obfs2/obfs3
 and flash proxy, then for obfs2/obfs3 you just need to turn on the `Bridge
 obfs2` and `Bridge obfs3` lines. For flash proxy, you want the single
 `Bridge flashproxy 0.0.1.0:1` line as well as `LearnCircuitBuildTimeout 0`
 and `CircuitBuildTimeout 60`.

 `LearnCircuitBuildTimeout` and `CircuitBuildTimeout` need some
 explanation. Without these settings, a flash proxy bridge will fail almost
 exactly 20% of the time--Tor will refuse to use it, even if it is the only
 bridge configured, and even if you got a connection to a browser proxy,
 which is the hard part. The reason is that `LearnCircuitBuildTimeout` is
 designed to learn a timeout that excludes the lowest 20% of circuits. When
 you connect over flash proxy, you are connecting through someone else's
 browser, so you never know how fast it will be. 20% of the time it will be
 too slow and leave you with a broken connection. There's a little writeup
 of the problem in
 [https://gitweb.torproject.org/flashproxy.git/commitdiff/a1bf13ae243428224fa49afc85add3e1b4d31e29
 this commit message]. `CircuitBuildTimeout` might not be necessary since
 we are shipping Tor 0.2.4 (see #6304), as it's set to the default value.

 That said, I think this ticket is worth doing even if it is only setting
 new `Bridge` lines and not any other settings.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10418#comment:4>
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