[tor-bugs] #25688 [Obfuscation/Snowflake]: proxy-go is still deadlocking occasionally

[Tor Bug Tracker & Wiki]

#25688: proxy-go is still deadlocking occasionally
--------------------------------------------+--------------------------
 Reporter:  dcf                             |          Owner:  cohosh
     Type:  defect                          |         Status:  assigned
 Priority:  Low                             |      Milestone:
Component:  Obfuscation/Snowflake           |        Version:
 Severity:  Normal                          |     Resolution:
 Keywords:  network-team-roadmap-2019-Q1Q2  |  Actual Points:
Parent ID:                                  |         Points:  3
 Reviewer:                                  |        Sponsor:
--------------------------------------------+--------------------------

Comment (by cohosh):

 Looking at the log output:

 A healthy sequence of events for a single token produces the following
 messages:
 {{{
 2019/03/29 21:52:53 broker returns: 504
 2019/03/29 21:52:56 sdp offer successfully received.
 2019/03/29 21:52:56 Generating answer...
 2019/03/29 21:52:57 OnDataChannel
 2019/03/29 21:52:57 OnOpen channel
 2019/03/29 21:52:57 connected to relay
 2019/03/29 21:53:31 OnClose channel
 2019/03/29 21:53:31 datachannelHandler ends
 }}}

 If we grep the logs for these messages we find:
 {{{
 $ grep "Generating" snowflake-proxy.log | wc -l
 1046
 }}}
 {{{
 $ grep "OnData" snowflake-proxy.log | wc -l
 1036
 }}}

 So my guess is that the token is being lost somewhere in {{{sendAnswer}}}.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/25688#comment:10>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online