[tor-project] Anti-censorship team monthly report: January 2020

[Philipp Winter]

Hi all,

Here's what the anti-censorship team has been up to in January 2020:

Snowflake
=========

* Debugged and wrote a Tor Browser patch to fix throughput issues with
  Snowflake on Windows.
  <https://bugs.torproject.org/32870>
  <https://bugs.torproject.org/31971>

* Started implementing a feature for proxies to conduct throughput tests
  before polling.
  <https://bugs.torproject.org/32711>

* Continued Snowflake network health measurements and analysis.
  <https://bugs.torproject.org/32545>

* David built a prototype that integrates Turbo Tunnel in Snowflake.
  Take a look at his detailed technical summary:
  <https://lists.torproject.org/pipermail/anti-censorship-team/2020-February/000059.html>

GetTor
======

* Fixed a bug in GetTor's email responder.
  <https://bugs.torproject.org/32906>

* Got GetTor's Gitlab distributor back up and running.
  <https://bugs.torproject.org/32711>

* Moved GetTor's Github repository and got it up and running.
  <https://bugs.torproject.org/32977>

* Modified GetTor to hand out localized binaries.
  <https://bugs.torproject.org/33002>

* Fixed up GetTor's tests to run locally.
  <https://bugs.torproject.org/33004>

* Filed a ticket on GetTor's problematic use of rate limiting.
  <https://bugs.torproject.org/33123>

BridgeDB
========

* Damian generously spent a lot of time and effort getting BridgeDB very
  close to supporting Python 3.  A handful of issues remain, but the
  bulk of the code base now support Python 3.
  <https://bugs.torproject.org/30946>

* Started working on a patch that allows BridgeDB to test its bridges
  using bridgestrap.  The idea is that broken bridges are logged
  (allowing us to inform the operator) and aren't handed out to users.
  <https://bugs.torproject.org/31874>

* Filed a ticket to display BridgeDB's distribution bucket for a bridge
  on Relay Search.
  <https://bugs.torproject.org/33008>

* Improved BridgeDB's CAPTCHAs.  We modified gimp-captcha (the script
  that BridgeDB uses to generate CAPTCHAs) to make the CAPTCHAs easier
  to solve.  Our BridgeDB usage metrics reveal that the success rate of
  our users increased from ~58% to ~87% after we deployed the new
  CAPTCHAs.  Take a look at the following comment for a more in-depth
  analysis:
  <https://bugs.torproject.org/24607#comment:13>

  It's still not perfect but it's a step forward.
  <https://bugs.torproject.org/24607>

Bridges
=======

* Coordinated the set up of a new default bridge in Denmark.  The
  bridge speaks both IPv4 and IPv6.  Thanks to Toke Høiland-Jørgensen
  for running this new default bridge!
  <https://bugs.torproject.org/32891>

* We did a retrospective analysis of our bridge campaign from September
  2019.  In particular, we tested how many bridges were still online
  (61%) and we sent an email to all operators.  We thanked the ones who
  are still running a bridge and we asked the ones whose bridge vanished
  what went wrong.
  <https://bugs.torproject.org/33007>

Outreach
========

* Philipp gave a talk at FH Hagenberg on the Tor network and censorship
  resistance:
  <https://www.fh-ooe.at/campus-hagenberg/die-fakultaet/aktuelles/news/news/internet-zensur-und-anonymitaet-im-tor-netzwerk-experten-vortrag-am-91-am-fh-ooe-campus-hagenberg/>
  Approximately 80-100 people attended -- mostly students but also a
  handful of faculty members and visitors.  Almost all have heard of Tor
  before and most have used it in the past.  There were plenty of
  questions at the end, and the event stopped before Philipp was able to
  answer them all.  All Tor stickers were gone almost instantly!

Miscellaneous
=============

* Added go.mod and go.sum to bridgestrap.
  <https://dip.torproject.org/phw/bridgestrap/commit/0e33599d6e6d1c0a809d5c59c51bdc823b7ebd2a>

* Coordinated with OONI on their new Tor test and its user
  interface.
  <https://github.com/ooni/backend/issues/305>
  <https://github.com/ooni/probe/issues/967>

* Made two minor fixes to obfs4portscan (the service behind
  <https://bridges.torproject.org/scan/>):

  1. Made it clear that the service supports IPv6 and expects IPv6
     addresses in square bracket notation.

  2. Made the service use GET instead of POST requests, to make it
     easier to hand people clickable links for their bridge.

* We roadmapped the following three months, ranging from February to
  April 2020.  Check out our team's wiki page for the goals of this
  roadmapping period:
  <https://trac.torproject.org/projects/tor/wiki/org/teams/AntiCensorshipTeam#Roadmappinggoals>

* Lots of work on an NSF "Transition to Practice" grant we have been
  working on.