[tor-bugs] #17376 [Tor Browser]: Cannot bootstrap over IPv6

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#17376: Cannot bootstrap over IPv6
-----------------------------+---------------------------------------
     Reporter:  sdstrowes    |      Owner:  tbb-team
         Type:  defect       |     Status:  new
     Priority:  Medium       |  Milestone:
    Component:  Tor Browser  |    Version:
     Severity:  Normal       |   Keywords:  torbrowser ipv6 bootstrap
Actual Points:               |  Parent ID:
       Points:               |    Sponsor:
-----------------------------+---------------------------------------
 Using the current public TorBrowser build, I cannot connect to the Tor
 network from some machines.

 torbrowser error dialog:

 {{{
 Tor failed to establish a Tor network connection.

 Connecting to a relay directory failed (no route to host -
 199.254.238.52:443).
 }}}
 torbrowser log:

 {{{
 18/10/2015, 21:46:46.600 [NOTICE] Opening Socks listener on 127.0.0.1:9150

 18/10/2015, 21:46:46.600 [NOTICE] Renaming old configuration file to
 "/Applications/TorBrowser.app/TorBrowser/Data/Tor/torrc.orig.1"

 18/10/2015, 21:46:46.600 [NOTICE] Bootstrapped 5%: Connecting to directory
 server

 18/10/2015, 21:46:46.600 [WARN] Problem bootstrapping. Stuck at 5%:
 Connecting to directory server. (Network is unreachable; NOROUTE; count 1;
 recommendation warn; host 7EA6EAD6FD83083C538F44038BBFA077587DD755 at
 194.109.206.212:443)

 18/10/2015, 21:50:13.000 [WARN] Problem bootstrapping. Stuck at 5%:
 Connecting to directory server. (Network is unreachable; NOROUTE; count 2;
 recommendation warn; host 847B1F850344D7876491A54892F904934E4EB85D at
 86.59.21.38:443)

 18/10/2015, 21:50:13.000 [WARN] Problem bootstrapping. Stuck at 5%:
 Connecting to directory server. (Network is unreachable; NOROUTE; count 3;
 recommendation warn; host F2044413DAC2E02E3D6BCF4735A19BCA1DE97281 at
 131.188.40.189:443)
 }}}
 Two of the addresses attempted here actually belong to hosts that have
 IPv6 connectivity: https://gist.github.com/sdstrowes/9e5cf5a3f2fe48ef3979
 These hosts have the correct ports open and are listening, but TorBrowser
 doesn't try to connect. It's not always the case that hosts at this stage
 have IPv6, but at least some do.

 References to 127.0.0.0/8 smells v4-specific, which isn't useful without
 IPv4 end-to-end. NAT64 won't help in this instance.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17376>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
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