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

[Philipp Winter]

Hi all,

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

Snowflake
---------

* Merged Turbo Tunnel features into Snowflake. (Allows persisting a
  session across separate proxies.)
  <https://bugs.torproject.org/33745>
  <https://lists.torproject.org/pipermail/tor-talk/2020-April/045571.html>

  Merging into Tor Browser is pending:
  <https://bugs.torproject.org/34043>

* Implemented measures to hand out more restrictive proxies less often.
  <https://bugs.torproject.org/33666>

* Split Snowflake into two repositories(one for Go, one for the
  web-based proxy code).
  <https://bugs.torproject.org/33593>

* Updated pion webrtc in Tor Browser.
  <https://bugs.torproject.org/33576>

BridgeDB
--------

* Moved forward with creating a feedback loop between OONI and BridgeDB.
  Work-in-progress code is available at:
  <https://gitlab.torproject.org/torproject/anti-censorship/wolpertinger>
  <https://bugs.torproject.org/32740>

* Removed PGP support from BridgeDB.  The feature has been broken for
  quite a while, is overly complex, and not particularly useful.
  <https://bugs.torproject.org/17548>

* Renamed a bunch of source code files in BridgeDB, so they no longer
  collide on a file system that's case insensitive.
  <https://bugs.torproject.org/29686>

* Made BridgeDB's email responder more usable.  The instructions are now
  more clear and it will return with bridges no matter what -- even if
  the user's request was malformed.
  <https://bugs.torproject.org/30941>

* Improved a Python script that tests BridgeDB's email responder by
  periodically sending email.
  <https://bugs.torproject.org/12802>

* Made progress towards improving the robustness of BridgeDB's email
  autoresponder, so it no longer gets confused by Gmail's
  quoted-printable responses.
  <https://trac.torproject.org/projects/tor/ticket/33835#ticket>

GetTor
------

* Fixed a bug caused by malformed email addresses.
  <https://bugs.torproject.org/34027>

* Refactored to remove duplicate code.
  <https://bugs.torproject.org/34035>

* Cleaned up logs.
  <https://bugs.torproject.org/34061>

* Fixed a bug in the service shutdown code.
  <https://bugs.torproject.org/34062>

* Removed a bunch of old GetTor code.
  <https://bugs.torproject.org/32912>


Miscellaneous
-------------

* Reviewed a submission for the Tor Research Safety Board.

* Moved forward with creating a "censorship snapshot" that encodes how
  each country blocks Tor.  Eventually, this snapshot should help Tor
  Browser figure out how to best circumvent in each country.
  <https://bugs.torproject.org/28531>

* Built a prototype of a lightweight censorship analyser that's meant to
  be run by censored users.  It can help us create the censorship
  snapshot in #28531.
  <https://bugs.torproject.org/30794>

* Created a new mailing list for anti-censorship service outage alerts.
  If this interests you, you can subscribe here:
  <https://lists.torproject.org/cgi-bin/mailman/listinfo/anti-censorship-alerts>

* We organised two reading groups, in which we discussed the following
  two papers:
  <https://censorbib.nymity.ch/#Wang2020a>
  <https://censorbib.nymity.ch/#Nasr2020a>

Cheers,
Philipp