Hey everyone!

Here are our meeting logs:

http://meetbot.debian.net/tor-meeting/2025/tor-meeting.2025-02-06-16.00.html

And our meeting pad:

Anti-censorship --------------------------------

Next meeting: Thursday,Feb 13 16:00 UTC Facilitator: meskio ^^^(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: shelikhoo

== 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 ==

* snowflake-broker.azureedge.net and meek-reflect.azureedge.net have stopped resolving as of 2025-02-04. https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... dcf will take care of decomissioning the instance

== Discussion ==

* snowflake with covertdtls builds - ask for testing (on Tor Forum)? * https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... * https://people.torproject.org/~cohosh/snowflake_covertdtls/ * theodorsm is debugging a possible issue where the snowflake client is rarely a DTLS client * we'll wait for it to ask others to test it

* Old Debian broker 10 has been turned off. Any problems? * https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... * meskio reports no change in grafana * dcf will need to reduce the resource allocation of the new broker in order to get it under the 50 EUR/month credit. * happened 2025-02-04 17:42:52 https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... * only thing we might want to save are the snowflake-broker logs, as in previous * https://archive.org/details/snowflake-broker-logs-20190416 * https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... * shelikhoo has additional logs from a before a disk-full event once * decision: * dcf will delete the old broker VPS without saving anything from the disk image * shelikhoo will delete the local copy of the logs from before the disk-full event

* Now that the broker resource allocation has been reduced for cost reasons, do we have monitoring in place to monitor the load and see how it is behaving? * https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... * ram usage is about 3258.7 of 8K * cpu is about 200% of 400% * There are small spikes in network bandwidth aligned to the start of every hour * meskio doesn't see any similar thing in grafana, like client polls are not happening hourly * on closer inspection, yes there are some spikes in client polls, per your, not as big as in the traffic graph * nginx is restarted every hour, on the hour, to check for new certificates. but that would be unlikely to affect the network.

== Actions ==

== Interesting links ==

* "Identifying VPN Servers through Graph-Represented Behaviors" * https://dl.acm.org/doi/10.1145/3589334.3645552 * https://dl.acm.org/doi/pdf/10.1145/3589334.3645552 * https://github.com/chenxuStep/VPNChecker

== Reading group ==

* We will discuss "Identifying VPN Servers through Graph-Represented Behaviors" on February 27 * https://dl.acm.org/doi/10.1145/3589334.3645552 * https://dl.acm.org/doi/pdf/10.1145/3589334.3645552 * https://github.com/chenxuStep/VPNChecker * 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): 2025-02-06 (away during meeting) Last week: - followed up on let's encrypt + meek email and review - changed broker's ClientTimeout (snowflake#40446) - tested meek-azure reachability and updated some bridge lines - reviewed lox!305 - debugged and helped plan conjure work This week: - review snowflake!315 - support conjure work - take a look at potential snowflake orbot bug - https://github.com/guardianproject/orbot-android/issues/1183 - maybe do some lox work dcf: 2025-02-06 Last week: - tracked status of snowflake-broker.azureedge.net after announced date of Edgio shutdown https://lists.torproject.org/mailman3/hyperkitty/list/anti-censorship-team@l... - helped debug reported "AMP cache rendezvous doesn't work in China" https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - commented on adding country to snowflake prometheus metrics https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - suggested color-scheme CSS for snowflake embed (rather than a query parameter or somesuch) https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - turned off the old Debian 10 broker, VPS still exists https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - restarted new broker with a lower-cost configuration https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... - snowflake broker VPS bookkeeping https://gitlab.torproject.org/tpo/anti-censorship/team/-/wikis/Snowflake-cos... 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: 2024-02-06 Last week: - map rdsys containers (rdsys#219) - fix the snowflake proxy prometheus coutry metrics MR (snowflake!482) - fixes for collector on bridgedb metrics (collector#40049) - remove meek azure (team#155) Next week: - steps towards a rdsys in containers (rdsys#219) - why is lyrebird not accepting https proxy (lyrebird#40024)

Shelikhoo: 2024-02-06 Last Week: - [Refine] Unreliable+unordered WebRTC data channel transport for Snowflake rev2 (cont.)( https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... ) improvements - [Review] covert-dtls - Merge request reviews Next Week/TODO: - Merge request reviews - [Refine] Unreliable+unordered WebRTC data channel transport for Snowflake rev2 (cont.)( https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... ) improvements

onyinyang: 2025-02-06 Last week(s): - continued work on ampcache registration method for conjure Next week: - finish up ampcache registration method (sqs on hold for now) - Begin work on either obfs4 transport or decoy registration option - add TTL cache to lox MR for duplicate responses: https://gitlab.torproject.org/tpo/anti-censorship/lox/-/merge_requests/305 As time allows: - 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: 2025-02-06 Last weeks: - Testing Tor Build with covert-dtls (troubleshooting becoming DTLS client and not seeing manipulated messages). Next weeks: - Update covert-dtls to handle new DTLS extensions in recent browsers - Write instructions on how to configure covert-dtls with snowflake client - Fix merge conflicts in MR (https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...). - Condensing thesis into paper (on hold) Help with: - Test stability of covert-dtls in snowflake

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