[tor-bugs] #12606 [Pluggable transport]: Refactor obfs4proxy (and the support protocol code)

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#12606: Refactor obfs4proxy (and the support protocol code)
-------------------------------------+--------------------------
     Reporter:  yawning              |      Owner:  yawning
         Type:  defect               |     Status:  needs_review
     Priority:  normal               |  Milestone:
    Component:  Pluggable transport  |    Version:
   Resolution:                       |   Keywords:  obfs4
Actual Points:                       |  Parent ID:  #12130
       Points:                       |
-------------------------------------+--------------------------

Comment (by yawning):

 Replying to [comment:6 asn]:
 > Also, it would be nice if obfs4proxy's logging was less heavy volume.
 attachment:obfs4_conns.log has a sample of what the logs look like in my
 bridge.
 >
 > As a bridge op, I regularly check obfspoxy logs to see if any new
 handshake log warnings have triggered (perhaps active scanning?), but if
 the log is so busy it's easy to lose information. Log severities or more
 strategic logging would be helpful.

 Go lang's default logging package doesn't support log leveling, so I would
 need to do this on my own, which is why the logging currently is only
 really useful when enabled and the scrubber disabled.  I figured that most
 bridge operators wouldn't enable logging except when debugging problems,
 for which disabling the scrubber would be ok.

 (Insert rant about how the debian go packaging and tbb build process
 combine to provide a rather large disincentive for using an existing 3rd
 party library by making it a huge pain to increase the number of
 dependencies.)

 > Also that ERROR "handshake failed" is probably someone who disconnected
 during the handshake, not something more serious, right?

 Probably, but because of the log scrubbing that I had to put in, it'll
 suppress the more interesting errors unless the log scrubber is disabled,
 so there's no way to tell at the moment.  I'll revise the code to only
 suppress go network errors and see if that's better.

 > fwiw I still haven't reviewed your new changes.

 Ok, no rush.  I'm looking to tag the current code (with the logging
 changes) soon-ish as long as no major problems show up.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/12606#comment:7>
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