- anti-censorship-team - lists.torproject.org

Couple of questions about Snowflake
by protonmailareliars 23 Nov '21

23 Nov '21

Hello all, First of all I really appreciate all the work that the anti-censorship team has been putting on building better censorship circumvention tools, and I hope snowflake becomes even more successful than obfs4. I have a few questions about current developments, 1. What's the status on Snowflake Mobile development? Looks like the last commit was more than 1 year old: https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snow… Is there any roadmap for getting it out? 2. Right now I assume the broker tends to hand out standalone-snowflake IPs first rather than web-ext-snowflake IPs (that's how it was working if I remember correctly, please correct me if I'm wrong). Is this still the case? I'm asking since I noticed a very impressive improvement when it comes to speed with snowflake and I would like to know if it was just due to me ending up with a standalone-snowflake or rather if issues with performance and speed got ironed out for web-ext-snowflakes. 3. The browser addon currently shows "Your snowflake has helped X users circumvent censorship in the last 24 hours". But this might be bad UX, it should be in the last week or even month since even though there are about ~2k snowflake users, the ratio of snowflakes/users is still big enough that a lot of users might be under the impression that they never helped any user/or that the extension isn't working correctly. 4. It might be a good idea to display the data in https://snowflake-broker.torproject.net.global.prod.fastly.net/metrics directly in https://metrics.torproject.org. Thanks in advance for any answers.

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Firefox Add-ons policy changes 2021-12-01
by David Fifield 09 Nov '21

09 Nov '21

Mozilla will change the policy for add-ons on December 1: https://blog.mozilla.org/addons/2021/11/03/add-on-policy-changes-2021/ https://extensionworkshop.com/documentation/publish/add-on-policies-dec-202… By my reading, the parts that may apply to us have to do with a privacy policy and possible consent form. From the blog: > If your add-on collects technical data, user interaction data, or > personal data, you must show a consent experience at the first run of > the add-on. > Most add-ons require a privacy policy. For add-ons listed on > addons.mozilla.org, the policy must be included in the listing in its > full text. I don't think the Snowflake add-on currently has a privacy policy on addons.mozilla.org.

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What is this
by enricocrivellaro2＠libero.it 03 Nov '21

03 Nov '21

-- Inviato da Libero Mail per Android

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Reboot of Snowflake VPSes is needed
by David Fifield 28 Oct '21

28 Oct '21

I got an email saying that the snowflake bridge and broker VPSes need to be restarted to migrate them to a new storage backend. If we don't do it, it will happen automatically some time next week. Is there a better time to schedule the restart? ----- Forwarded message from "eclips.is" <support(a)eclips.is> ----- Date: Wed, 27 Oct 2021 11:52:08 +0000 From: "eclips.is" <support(a)eclips.is> Dear eclips.is user, We are performing an update on our virtualization platform, this requires a change in the configuration of the storage backend. Due to this update your VPS needs to be stopped/started. We will execute this for you next week. If you prefer to plan this on your own, please feel free to stop/start your VPS yourself. By doing so, the VPS will be moved to the updated platform. Note: A reboot from within the machine itself will not be sufficient. ----- End forwarded message -----

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configure router NAT for snowflake proxy
by meskio 25 Oct '21

25 Oct '21

Hello, I thought I could host a snowflake standalone proxy in my home fiber. Following the instructions[0] it says that is "especially recommended": > A full-cone NAT (you can use this NAT behaviour tool to test what type of NAT > you have. The properties you are looking for are address-independent mapping > and either address-independent or address-dependent filtering) Using the "NAT behaviour tool" I get: * NAT mapping behavior: endpoint independent (good) * NAT filtering behavior: address and port dependent (bad) My home router is an openwrt on which I have total control, it gets the public IP from my ISP and provides NAT to my home network. I tried playing a bit with the NAT Rules and the firewall settings, but all that is magic for me. Any tips how to fix the NAT filtering in openwrt or what do I need to look into iptables for it? Thanks. [0] https://community.torproject.org/relay/setup/snowflake/standalone/ -- meskio | https://meskio.net/ -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- My contact info: https://meskio.net/crypto.txt -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Nos vamos a Croatan.

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SCTP-Based Pluggable Transport Prototype
by Alexander Mages 18 Sep '21

18 Sep '21

Hello Anti-Censorship Team, I was advised by Cecylia to share my project with this mailing list for the wider community to see and critique. For the past couple of months, I have been doing research under the advisory of Prof. Eugene Vasserman (CC) at Kansas State University, and this project is the result. I intend to continue working on privacy and anonymity, so if this project has potential I would be happy to keep working on it, as well as exploring other ways to contribute. The concept for this transport was derived from this wiki page: https://gitlab.torproject.org/legacy/trac/-/wikis/doc/PluggableTransports/i… . The transport is functional but not yet tested with the Tor Browser. I prototyped this transport using Ncat for SCTP and Telnet for TCP. It is written in Python 3 and SCTP functionality was implemented using C/POSIX-like socket parameters, removing the necessity of a third-party library. A write-up attached to this email denotes functionality, dependencies, limitations, and instructions for running the transport. I look forward to hearing everyone's thoughts! Regards, Alex Mages

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ansible role - snowflake - updates
by Jacobo Nájera 27 Aug '21

27 Aug '21

Hello, I added new features to the ansible role of snowflake: - Support for: Debian Bullseye and Ubuntu Focal - Variable to update the standalone version of Snowflake If you are using the ansible role you can update snowflake via your playbook. First, upgrade ansible role ansible-galaxy install -f nvjacobo.snowflake Then add snowflake_update var: - hosts: all vars: snowflake_update: yes roles: - nvjacobo.snowflake Finally run your playbook. Documentation of ansible role snowflake: https://www.jacobo.org/en/ansible-for-snowflake-proxies-of-the-tor-network/ Thanks, Jacobo

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Improving Snowflake performance by adjusting smux parameters
by David Fifield 04 Aug '21

04 Aug '21

While experimenting with another tunnel built on KCP and smux, I discovered that performance could be greatly increased by increasing the size of smux buffers. It's likely that doing the same can also improve performance in Snowflake. There are two relevant parameters, MaxReceiveBuffer and MaxStreamBuffer. MaxStreamBuffer seems to be the most important one to increase. https://pkg.go.dev/github.com/xtaci/smux#Config // MaxReceiveBuffer is used to control the maximum // number of data in the buffer pool MaxReceiveBuffer int // MaxStreamBuffer is used to control the maximum // number of data per stream MaxStreamBuffer int The default values are 4 MB and 64 KB. https://github.com/xtaci/smux/blob/eba6ee1d2a14eb7f86f43f7b7cb3e44234e13c66… MaxReceiveBuffer: 4194304, MaxStreamBuffer: 65536, kcptun, a prominent KCP/smux tunnel, has defaults of 4 MB (--smuxbuf) and 2 MB (--streambuf) in both client and server: https://github.com/xtaci/kcptun/blob/9a5b31b4706aba4c67bcb6ebfe108fdb564a90… In my experiment, I changed the values to 4 MB / 1 MB on the client and 16 MB / 1 MB on the server. This change increased download speed by about a factor of 3: default buffers 477.4 KB/s enlarged buffers 1388.3 KB/2 Values of MaxStreamBuffer higher than 1 MB didn't seem to have much of an effect. 256 KB did not help as much. My guess, based on intuition, is that on the server we should set a large value of MaxReceiveBuffer, as it is a global limit shared among all clients, and a relatively smaller value of MaxStreamBuffer, because there are expected to be many simultaneous streams. On the client, don't set MaxReceiveBuffer too high, because it's on an end-user device, but go ahead and set MaxStreamBuffer high, because there's expected to be only one or two streams at a time. I discovered this initially by temporarily settings smux to protocol v1 instead of v2. My understanding is that v1 lacks some kind of receive window mechanism that v2 has, and by default is more willing to expend memory receiving data. See "Per-stream sliding window to control congestion.(protocol version 2+)": https://pkg.go.dev/github.com/xtaci/smux#readme-features Past performance ticket: "Reduce KCP bottlenecks for Snowflake" https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snow…

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Snowflake in action
by Jacobo Nájera 14 Jul '21

14 Jul '21

Hi, I wrote about my experience running snowflake proxies by standalone version. I did an analysis about hardware resources and standalone version by 4 setups. Spanish: https://www.jacobo.org/ansible-snowflake/ English: https://www.jacobo.org/en/snowflake-in-action/ More analysis soon. Thanks, Jacobo

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Do we expect to have as many standalone Snowflake proxies as we do?
by David Fifield 08 Jul '21

08 Jul '21

I was looking at https://snowflake-broker.torproject.net/debug just now, and saw: current snowflakes available: 317 standalone proxies: 216 browser proxies: 0 webext proxies: 101 unknown proxies: 0 NAT Types available: restricted: 278 unrestricted: 2 unknown: 37 About 2/3 of proxies are standalone, which is more than I would have supposed. Has there been word getting out about how to run one, or something?

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