Hey everyone! Here are our meeting logs: http://meetbot.debian.net/tor-meeting/2025/tor-meeting.2025-07-10-16.01.html And our meeting pad: Anti-censorship work meeting pad -------------------------------- Anti-censorship -------------------------------- Next meeting: Thursday, July 17 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 ==     * == Discussion == (July 10 New:) == Actions == == Interesting links == (July 10 New:)     * https://github.com/net4people/bbs/issues/496 TLSMirror: Looks like TLS Censorship Resistant Transport Protocol is Looking for Developer Feedback == 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): 2025-07-10     Last week:         - found and fixed regression in snowflake prometheus stats (snowflake#40470)         - met with new conjure bridge operator (conjure#46)         - added June Snowflake SQS costs https://gitlab.torproject.org/tpo/anti-censorship/team/-/wikis/Snowflake-cos...         - added a clarification to the broker metrics spec (snowflake!577)         - updated discussion on client rendezvous errors (snowflake#40447)         - fixed up client-polls merge request in snowflake-graphs             - https://gitlab.torproject.org/dcf/snowflake-graphs/-/merge_requests/1         - opened issue to follow up on reports of short-lived client connections (snowflake#40471)     This week:         - snowflake-webext version bump and deployment         - follow-up on new conjure bridge set up(conjure#46)         - start work around snowflake enumeration attacks             - https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...         - follow up on snowflake rendezvous failures         - take a look at potential snowflake orbot bug             - https://github.com/guardianproject/orbot-android/issues/1183 dcf: 2025-07-10     Last week:         - further commenting on a FEP design https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/lyreb...         - snowflake VPS bookkeeping https://gitlab.torproject.org/tpo/anti-censorship/team/-/wikis/Snowflake-cos...         - readjusted the snowflake broker resource allocation downward to what it had been before the Iran shutdown https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...         - made graphs of snowflake usage during the Iran shutdown https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...         - did review of client-polls.csv MR in snowflake-graphs https://gitlab.torproject.org/dcf/snowflake-graphs/-/merge_requests/1         - opened a Dockerfile MR on behalf of an external user https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...         - speculated on snowflake proxy WebRTC connections preventing computer from sleeping https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...         - answered a WebTunnel failure report, weirdly the cause seems to be DNS https://gitlab.torproject.org/tpo/anti-censorship/censorship-analysis/-/issu...     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... Help with: meskio: 2024-06-26     Last week:         - merge the contaners of rdsys and bridgestrap, the staging server is life...         - investigate the changes in webtunnel used in russia to bypass censors (censorship-analisys#40064)         - test snowflake proxy patch for Iran (snowflake#40465)         - support grant writting     Next week:         - AFK Shelikhoo: 2024-07-10     Last Week:          - [Testing] Unreliable+unordered WebRTC data channel transport for Snowflake rev2 (cont.)( https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf... ) testing environment setup/research         - [Invesgate, Deployment] Meek Bridge Offline, we should consider switching to anther hosting provider(https://gitlab.torproject.org/tpo/anti-censorship/team/-/issues/162)         - [Merge Request] Bug 41508: Switch built-in meek bridge to meek-unredacted (https://gitlab.torproject.org/tpo/applications/tor-browser-build/-/merge_req...)         - Vantge point maintaince         - Merge request reviews     Next (working) Week/TODO:         - Merge request reviews         - Support the Testing of domain fronting sites ( https://gitlab.torproject.org/tpo/anti-censorship/connectivity-measurement/l... ) (cont.) onyinyang: 2025-07-10     Last week(s):        - Mid-year break         - Finished up work on  webtunnel distribution through telegram:             - https://gitlab.torproject.org/tpo/anti-censorship/team/-/issues/158#note_321...             - https://gitlab.torproject.org/tpo/anti-censorship/rdsys/-/merge_requests/534         - Looking into bridge distribution issues: https://gitlab.torproject.org/tpo/anti-censorship/rdsys/-/issues/267           - Related to rdsys-admin update on 06/26?             - restarted rdsys to see if that helps         - Next is looking into this mystery: https://gitlab.torproject.org/tpo/anti-censorship/rdsys/-/issues/262#note_32... Next week:       Finish up webtunnel work on rdsys       Blog post for conjure: https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/conju...       Switch back to some of these:           As time allows:               - review Tor browser Lox integration https://gitlab.torproject.org/tpo/applications/tor-browser/-/merge_requests/...               - add TTL cache to lox MR for duplicate responses: https://gitlab.torproject.org/tpo/anti-censorship/lox/-/merge_requests/305         - 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: 2025-06-12         Last weeks:             - Applying for funding from NLnet to implement DTLS 1.3 in Pion. Got through the first round.             - Writing paper for FOCI: continuation of master thesis about reducing distinguishability of DTLS in Snowflake by implementing covert-dtls, further analysis of collected browser fingerprint and stability test of covert-dtls in snowflake proxies. Draft: https://theodorsm.net/FOCI25             - Key takeaways:                 * covert-dtls is stable when mimicking DTLS 1.2 handshakes, while the randomization approach— though more resistant to fingerprinting — tends to be less stable.                 * Chrome webextensions are more unstable than standalone proxies                 * covert-dtls should be integrated in Snowflake proxies as they produce the ClientHello messages during the DTLS handshake.                 * Chrome randomizes the order of extension list.                 * Firefox uses DTLS 1.3 by default in WebRTC.                 * A prompt adoption of DTLS 1.3 in both Snowflake and our fingerprint-resistant library is needed to keep up with browsers                 * The evolution of browsers’ fingerprints had no noticeable effect on Snowflake’s number of daily users over the last year.                 * Even with a sharp drop in the amount of proxies, it does not seem to affect the number of Snowflake users.                 * Browser extensions make Snowflake resistant to ClientHello fingerprinting.                 * Standalone proxies can serve more Snowflake clients per volunteer than webextensions.                 * We need metrics on which types of proxies are actually being matched and successfully used by clients.         Next weeks:             - Getting paper camera ready.             - Fix merge conflicts in MR (https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowf...).         Help with:             - Should we do user testing of covert-dtls? 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