Hi everyone!

Here are our meeting logs:

http://meetbot.debian.net/tor-meeting/2021/tor-meeting.2021-08-19-16.00.html

and our meeting pad:

Anti-censorship work meeting pad --------------------------------

Next meeting: Thursday August 19th 16:00 UTC

Weekly meetings, every Thursday at 16:00 UTC, in #tor-meeting at OFTC (channel is logged while meetings are in progress)

== Goal of this meeting ==

Weekly checkin about the status of anti-censorship work at Tor. Coordinate collaboration between people/teams on anti-censorship at Tor.

== Announcements ==

Job opening on the anti-censorship team: https://www.torproject.org/about/jobs/software-developer-anticensorship-2/ \o/

== Discussion ==

- v3 of the webext manifest doesn't support creating peerconnections in the background - last time: - we will present our need to https://github.com/w3c/webrtc-extensions/issues/77 to encourage them to permit WebRTC in service workers - no updates this week: cohosh will take over drafting a comment for the linked issue

- Tor and obfs4/meek blocking in TM: https://gitlab.torproject.org/tpo/community/support/-/issues/40030 - last time: - https://metrics.torproject.org/userstats-relay-country.html?start=2021-05-14... - ggus found a volunteer to help with testing. obfs4, meek-azure, and snowflake did not work; a private obfs4 bridge worked. - http://emma.mhgb.net/ was not reachable, so ggus set up a mirror at http://emma.gus.computer/ - our tester is having difficulty installing a recent Tor browser on an old Windows computer - will ask to install ooniprobe - cohosh will ask OONI (arturo and maria) for contacts in TM

- Snowflake reporting its own connection failures and sending messages to tor logs - https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - useful for diagnosing failures to connect, by users or our own testing, without having to enable the snowflake-client log file - e.g. using PT protocol LOG or STATUS messages

- Ukraine is experiencing an increase in relay users - https://metrics.torproject.org/userstats-relay-country.html?country=ua - in the past this was due to a browser bundling tor for anti-blocking purposes - https://gitlab.torproject.org/tpo/anti-censorship/censorship-analysis/-/issu...

== Interesting links ==

USENIX Security 2021 papers https://www.usenix.org/conference/usenixsecurity21/technical-sessions

"Domain Shadowing: Leveraging Content Delivery Networks for Robust Blocking-Resistant Communications" https://www.usenix.org/conference/usenixsecurity21/presentation/wei

"How Great is the Great Firewall? Measuring China's DNS Censorship" https://www.usenix.org/conference/usenixsecurity21/presentation/hoang

"Balboa: Bobbing and Weaving around Network Censorship" https://www.usenix.org/conference/usenixsecurity21/presentation/rosen

"Weaponizing Middleboxes for TCP Reflected Amplification" https://www.usenix.org/conference/usenixsecurity21/presentation/bock

"Defeating DNN-Based Traffic Analysis Systems in Real-Time With Blind Adversarial Perturbations" https://www.usenix.org/conference/usenixsecurity21/presentation/nasr

== Reading group ==

We will discuss "" on

Questions to ask and goals to have:

What aspects of the paper are questionable?

Are there immediate actions we can take based on this work?

Are there long-term actions we can take based on this work?

Is there future work that we want to call out, in hopes that others will pick it up?

== Updates ==

Name: This week: - What you worked on this week. Next week: - What you are planning to work on next week. Help with:

- Something you need help with.

cecylia (cohosh): last updated 2021-08-19 Last week: - hiring tasks for ac team and network team - 3 full days of s28 integration/scrimmage prep x_x - checked on censorship measurement tests - looked in TM blocking of Tor bridges (support#40030) - parse SOCKS args for Snowflake (snowflake#40059) This week: - more hiring and s28 meetings - censorship measurement tests and tools - help the browser team with tor's autoconnect feature - reviews - rdsys!11 - snowflake!52 followup - snowflake#25595 followup - follow up on OONI tor tests - lots of miscellaneous gitlab TODOs Needs help with:

arlolra: 2021-08-12

Last week:

- Migrate to v3 of the webextension manifest

Next week:

- Maybe get back to snowflake-webext #10

- Write up the pitch for our use case for supporting creating PeerConnections in background service workers https://github.com/w3c/webrtc-extensions/issues/77

Help with:

-

dcf: 2021-08-19

Last week:

- snowflake CDN bookkeeping https://gitlab.torproject.org/tpo/anti-censorship/team/-/wikis/Snowflake-cos...

- posted a summary of the Turkmenistan situation https://ntc.party/t/recent-drop-in-tor-users-from-turkmenistan-testers-wante... https://gitlab.torproject.org/tpo/community/support/-/issues/40030

Next week:

Help with:

agix:2021-07-15

Last week:

-Off due to final exams

Next week:

-Work on bridgebox for rdsys

-More research on httpt #4

Help with:

-

maxb: 2021-07-15

Last week:

- Opened https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... re: utls for broker negotiation

- Worked on github.com/max-b/nat-testing for https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...

- Added a snowflake-proxy-no-nat and a snowflake-client-no-nat to help with debugging

- Successfully making connections from snowflake-client and snoflake-client-no-nat through the snowflake-proxy-no-nat, but not having any success with the snowflake-proxy (with nat).

- Added a local dockerized STUN server

Next week:

- Use wireshark to figure out the difference between successful snowflake-proxy-no-nat and unsuccessful snowflake-proxy-nat

- Work on implementing different NAT types, particularly in a way that's conducive to automatic testing

- Add testing wrapper w/ "pass/fail" conditions

meskio: 2021-08-19

Last week:

- catch up after 3 weeks AFK (still in process)

- debug bridgestrap CollecTor metrics and why are not produced (bridgestrap#22)

- review bridgestrap fix to test only uncached bridges (bridgestrap!11)

- review bridgedb parse X-Forwarded-For header properly (bridgedb!21)

- review snowflake SOCKS arguments (snowflake!53)

Next week:

- make bridgestrap CollecTor metrics resistant to restarts (bridgestrap#22)

- change bridgedb to send obfs4 bridges by default over email (bridgedb#50)

- gettor in rdsys architecture documentation (rdsys#44)

- make a proposal for duplicated tests in bridgestrap CollecTor metrics (bridgestrap#23)

Help with:

-