[tor-bugs] #21136 [Obfuscation/Obfsproxy]: obfs4proxy doesn't listen on both 0.0.0.0 and [::]

[Tor Bug Tracker & Wiki]

#21136: obfs4proxy doesn't listen on both 0.0.0.0 and [::]
-----------------------------------+-------------------------
 Reporter:  kaie                   |          Owner:  kaie
     Type:  defect                 |         Status:  closed
 Priority:  Medium                 |      Milestone:
Component:  Obfuscation/Obfsproxy  |        Version:
 Severity:  Normal                 |     Resolution:  wontfix
 Keywords:                         |  Actual Points:
Parent ID:                         |         Points:
 Reviewer:                         |        Sponsor:
-----------------------------------+-------------------------

Comment (by yawning):

 The spec explicitly forbids the behavior you want, and just because it's
 binding to addresses, it doesn't mean that it's actually doing everything
 correctly under the hood.

 In particular:
  * #7961 isn't fixed.
  * Both listeners will generate separate key pairs, but the code only
 supports a single state file, so the bridge line that clients will use
 will change if you ever restart tor.
  * How `TOR_PT_SERVER_TRANSPORT_OPTIONS` should be handled is unclear.
 The way goptlib is implemented now, it only supports a single set of
 arguments per transport, which is likely incorrect.

 If anything, the fact that it doesn't throw an `ENV-ERROR` when there
 happen to be multiple instance of the same transport is a bug.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/21136#comment:6>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online