Hey everyone!
Here are our meeting logs: http://meetbot.debian.net/tor-meeting/2024/tor-meeting.2024-12-19-16.00.html
And our meeting pad:
Anti-censorship --------------------------------
Next meeting: Thursday,January 9 16:00 UTC Facilitator: onyinyang ^^^(See Facilitator Queue at tail)
Weekly meetings, every Thursday at 16:00 UTC, in #tor-meeting at OFTC (channel is logged while meetings are in progress)
This week's Facilitator: meskio
== Goal of this meeting ==
Weekly check-in about the status of anti-censorship work at Tor. Coordinate collaboration between people/teams on anti-censorship at the Tor Project and Tor community.
== Links to Useful documents == * Our anti-censorship roadmap: * Roadmap:https://gitlab.torproject.org/groups/tpo/anti-censorship/-/boards * The anti-censorship team's wiki page: * https://gitlab.torproject.org/tpo/anti-censorship/team/-/wikis/home * Past meeting notes can be found at: * https://lists.torproject.org/pipermail/tor-project/ * Tickets that need reviews: from projects, we are working on: * All needs review tickets: * https://gitlab.torproject.org/groups/tpo/anti-censorship/-/merge_requests?sc... * Project 158 <-- meskio working on it * https://gitlab.torproject.org/groups/tpo/anti-censorship/-/issues/?label_nam...
== Announcements ==
* Azure CDN from Edgio (azureedge.net) is due to be shut down as early as 2025-01-15: https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... * We stopped using snowflake-broker.azureedge.net in 2021: https://gitlab.torproject.org/tpo/applications/tor-browser-build/-/merge_req... * But it still receives traffic somehow: https://gitlab.torproject.org/tpo/anti-censorship/team/-/wikis/Snowflake-cos... * onionwrapper still uses snowflake-broker.azureedge.net: https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... * (also, anything still using snowflake-broker.azureedge.net is using the old broker not working right now, see discussion below) * No meetings during the next two weeks. Next meeting: January 9th
== Discussion ==
* Azure CDN from Edgio shutdown * Might make our meek builtin bridge stop working, requiring a change or removal as a default option * cohosh will follow up with micah * added a CDN77 meek bridge to the builtin bridges * going to change azure to ampcache, or sqs for China * https://gitlab.torproject.org/tpo/anti-censorship/rdsys-admin/-/merge_reques... * alternative domain names for CDN77 domain front * we are using phpmyadmin.net as domian front for snowflake, meek and moat * should we diversify? * https://forum.torproject.org/t/tor-and-hetzner-block-in-russia/16134/3 * tiktok domains? * in China there is a domestic version called douyin, tiktok itself may not be accessible? * shelikhoo will add support for testing domainfronts in vantage points to see what works where * snowflake-broker.azureedge.net (Edgio) became broken after being changed to point to snowflake-broker.torproject.net (the newly set up broker), because of some TLS certificate verification error between the CDN server and the broker origin. * https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... * The suspicion is that the Edgio CDN server is, for some reason, sending a incorrect SNI ("snowflake-broker.bamsoftware.com"; i.e., the old broker, which is how it was initially set up), even though all visible configuration options have been changed to say "snowflake-broker.torproject.net" instead. * Sample SNIs reaching the broker to see if snowflake-broker.bamsoftware.com is among them? * tshark -i eth0 -f 'dst port 443' -Y 'ssl.handshake.extension.type == "server_name"' -T fields -e tls.handshake.extensions_server_name * If so, then we could point the DNS record for snowflake-broker.bamsoftware.com at the new broker, and let the new broker generate certificates for that name, for as long as the Edgio CDN still holds out. * dcf will run the tshark command and report in #40427 * covert-dtls in snowflake client and standalone proxy -- is there a plan for volunteer testing before merging? * https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... * the recent partial blocking in Russia has ended, so asking for user testing there won't reveal whether the changed fingerprint makes a difference * but it still could be valuable to have users run with the patch as a kind of integration and interoperability test * need to test both standalone proxy and client * meskio can try running the patch on a standalone proxy * (but there's no way to get per-country statistics) * covert-dtls should be tested in both modes: randomize and mimic * theodorsm will produce instructions on how to compile and test the client with the help of cohosh * and nina will translate to post it in ntc.party
== Actions ==
== Interesting links ==
* https://dl.acm.org/doi/10.1145/3589334.3645656 * Discovering and Measuring CDNs Prone to Domain Fronting (2024, open access) * https://ieeexplore.ieee.org/document/10190674 * Assessing and Exploiting Domain Name Misinformation (2023, not open access)
== Reading group ==
* We will discuss "Discovering and Measuring CDNs Prone to Domain Fronting" on January 16th * https://dl.acm.org/doi/10.1145/3589334.3645656 * 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): 2024-12-19 Last week: - gitlab reviews and todos - more work on snowflake broker metrics improvements - handled meek builtin bridge update and azure edge shutdown This week: - afk for a few weeks dcf: 2024-12-19 Last week: - worked on making the Edgio CDN snowflake-broker.azureedge.net point to the new broker, but ran into problems with TLS certificate verification https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... - opened an issue for an error in the Snowflake Broker Survival Guide: the documented way to read the broker logs doesn't work https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - opened an issue to clean up the way multiple server names are handled on the snowflake broker https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - archived snowflake-webextension 0.9.0 and 0.9.2 https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... https://archive.org/details/snowflake-webextension-0.9.0 https://archive.org/details/snowflake-webextension-0.9.2 - answered questions from a student interested in experimenting with media streams in snowflake Next week: - open issue to have snowflake-client log whenever KCPInErrors is nonzero https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - parent: https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - open issue to disable /debug endpoint on snowflake broker Help with:
meskio: 2024-12-19 Last week: - grant writting world - catching up with things from and after SplinterCon Next week: - winter break
Shelikhoo: 2024-12-19 Last Week: - [Pending] snowflake broker update/reinstall(cont.): https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - [Awaiting Review] Unreliable+unordered WebRTC data channel transport for Snowflake rev2 (cont.)( https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... ) improvements - Merge request reviews - Analysis Iran vantage point result Next Week/TODO: - Merge request reviews - [Resume] Unreliable+unordered WebRTC data channel transport for Snowflake rev2 (cont.)( https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... ) improvements - Analysis Iran vantage point result
onyinyang: 2024-12-19 Last week(s): - Deployed test distributor - endpoints are available @ lox-test.torproject.org - Updated lox protocols to return duplicate responses for an already seen request Next week: - Break - Continue work on implementing issuer efficiency for check-blockage and trust-promotion protocols - Work on outstanding milestone issues: - key rotation automation Later: pending decision on abandoning lox wasm in favour of some kind of FFI? https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/43096): - add pref to handle timing for pubkey checks in Tor browser - add trusted invitation logic to tor browser integration: https://gitlab.torproject.org/tpo/applications/tor-browser/-/issues/42974 - improve metrics collection/think about how to show Lox is working/valuable - sketch out Lox blog post/usage notes for forum (long term things were discussed at the meeting!): - brainstorming grouping strategies for Lox buckets (of bridges) and gathering context on how types of bridges are distributed/use in practice Question: What makes a bridge usable for a given user, and how can we encode that to best ensure we're getting the most appropriate resources to people? 1. Are there some obvious grouping strategies that we can already consider? e.g., by PT, by bandwidth (lower bandwidth bridges sacrificed to open-invitation buckets?), by locale (to be matched with a requesting user's geoip or something?) 2. Does it make sense to group 3 bridges/bucket, so trusted users have access to 3 bridges (and untrusted users have access to 1)? More? Less? theodorsm: 2024-12-19 Last weeks: - WIP MR: Add covert-dtls to proxy and client - https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... Next weeks: - Fix merge conflicts in MR. - Write instructions on how to configure covert-dtls with snowflake client - Condensing thesis into paper (on hold) Help with: - Test stability of covert-dtls in snowflake MR
Facilitator Queue: meskio onyinyang shelikhoo 1. First available staff in the Facilitator Queue will be the facilitator for the meeting 2. After facilitating the meeting, the facilitator will be moved to the tail of the queue