- tor-dev - lists.torproject.org

Multi-threading throughout
by Todd Hubers 09 Jan '19

09 Jan '19

There are early plans to distribute crypto operations across multiple cores [https://trac.torproject.org/projects/tor/ticket/1749] but there might be a better way. (I registered, but I couldn't find a way to annotate the ticket, so I'm emailing for now) The ticket states the reason being to saturate the bandwidth available (by using all the cores as efficiently as possible). I don't understand why a relay needs to have a "main thread". Network traffic arrives as an async operation and can be sent back out asynchronously. So a final strategy shouldn't have a central thread. The main thread might still be needed for startup, runtime adjustment, and system upkeep, but not for the core network-crypto processing; that should never need to touch the main thread. The current proposal speaks about multi-threading crypto operations, let's call that "A) Speed - Speeding up processing of a single cell". Instead, I propose "B) Concurrency - Restructuring so multiple cells can be processed concurrently". A cell of data should arrive via IO-Completion thread on a random CPU core, have crypto transformation applied on the same one core, then be dispatched onward out via the network. This seems to be quite a simple approach where I would think crypto code can remain the same "single-threaded" implementation. Approach [A] will have diminishing returns as the number of cores increases. You can only break up a cell unit of work so much until you're encrypting one byte per cpu core. However, with approach [B], if you have millions of CPU cores (as an extreme) you can be processing millions of cells concurrently. Therefore, I believe approach [B] would be more scalable. What do you think? Regards, -- -- Todd Hubers

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Network team meeting Tuesday at 2300 UTC
by Gaba 04 Jan '19

04 Jan '19

Hi! The first network team meeting of the year is on Tuesday January 8th at 2300 UTC. The meeting will be at #tor-meeting on OFTC. Agenda and updates for weekly meetings this year are in: https://pad.riseup.net/p/tor-netteam-2019.1-keep cheers, gaba

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Upcoming Tor change with application impact: "Dormant Mode"
by Nick Mathewson 04 Jan '19

04 Jan '19

Hello! This email is about a new feature that has some implications here for applications that use Tor. I want to make sure we've thought about and prepared for those implications, since we still have time to tweak this feature. == Overview In 0.4.0.x, Tor will begin supporting a new "dormant" mode in which it does not initiate network activity, and tries to avoid CPU wakeups. This mode is intended to help mobile devices sleep, and to minimize the impact of unused Tor clients on the network, and on the devices that run them. For the implementation history, see: https://trac.torproject.org/projects/tor/ticket/28335 and https://trac.torproject.org/projects/tor/ticket/28624 By default, Tor will become dormant if it is a pure client (not a relay, not an onion service[*]), and if it has received not client activity for 24 hours. (You can change the interval with DormantClientTimeout.) Unlike "DisableNetwork 1", Tor in dormant mode will not close any listener ports, and will become active again as soon as it receives a client connection. But like a "DisableNetwork 1" Tor, a dormant Tor will not build predicted circuits, and will not download directory information -- and therefore, will not bootstrap. Controllers can make Tor become dormant or non-dormant by sending the commands "SIGNAL DORMANT" and "SIGNAL ACTIVE" respectively -- these are now documented in control-spec.txt. Dormant state is persistent: if Tor has been idle for 20 hours, and you stop tor and start it again, and idle for 4 more hours, Tor will become dormant. If you stop tor and start it again, Tor will start in dormant mode. == Documentation Here's the documentation we have so far -- please let me know if you have ideas for clarification: DormantClientTimeout N minutes|hours|days|weeks If Tor spends this much time without any client activity, enter a dormant state where automatic circuits are not built, and directory information is not fetched. Does not affect servers or onion services. Must be at least 10 minutes. (Default: 24 hours) DormantTimeoutDisabledByIdleStreams 0|1 If true, then any open client stream (even one not reading or writing) counts as client activity for the purpose of DormantClientTimeout. If false, then only network activity counts. (Default: 1) DormantOnFirstStartup 0|1 If true, then the first time Tor starts up with a fresh DataDirectory, it starts in dormant mode, and takes no actions until the user has made a request. (This mode is recommended if installing a Tor client for a user who might not actually use it.) If false, Tor bootstraps the first time it is started, whether it sees a user request or not. After the first time Tor starts, it begins in dormant mode if it was dormant before, and not otherwise. (Default: 0) == Compatibility issues I see two issues here: one minor, and one major. Minor issue: some applications periodically make requests to the tor network on their own -- for example, Tor Browser's update requests. These requests prevent Tor from becoming dormant. If this is undesired, we can add some way around this. Major issue: some applications expect that Tor will always bootstrap when it starts, and delay presenting their own UI until Tor is ready. But if Tor starts as dormant, then it will not bootstrap until it receives a request from the client or a "SIGNAL ACTIVE" command from the controller. This could lead to breakage as the application waits for Tor to tell it that it's ready, and Tor waits for somebody to tell it that it's needed. Are all application developers okay with the issues above, and okay with working around them? If not, we may need changes in Tor before 0.4.0.x is released. Let's talk! [*] I'd like to add support for dormant onion services, but that's harder. See https://trac.torproject.org/projects/tor/ticket/28424 . peace, -- Nick

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Queries regarding Summer of Privacy 2019
by Pranav Vardia 04 Jan '19

04 Jan '19

Hi, I am Pranav Vardia , third year student from International Institute of Information Technology, Bangalore. I am writing this mail to clarify few of my queries regarding Summer of Privacy. Firstly, I would like to ask that is there a list of projects whcih we can work on or do we need to come up with our own proposal ? Secondly, I cannot find any timeline and project lists for previous years Summer of Privacy. It would be great if you could provide me links to the aforementioned. Regards, Pranav Vardia

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HTTPS and Tor Onion v3 Services
by Nathaniel Suchy 28 Dec '18

28 Dec '18

Hi everyone, So I have an idea which may or may not be a possibility. Currently Tor Onion Services do not need HTTPS since they are already end to end encrypted. That said multiple layers of crypto cannot hurt, Facebook for example uses this approach. So I have the idea of some sort of mechanism that lets you sign a self-signed tls certificate with your Onion Service's hs_ed25519_secret_key and Tor Browser trusting the tls certificate based on this signature. Would this approach work? Would it be worth the effort? Look forward to hearing your thoughts :) Cordially, Nathaniel Suchy

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Re: [tor-dev] Regarding projects and a begineer guide.
by teor 21 Dec '18

21 Dec '18

Hi, Here's the torsocks README: https://gitweb.torproject.org/torsocks.git/tree/README.md You could start by building and installing torsocks: https://gitweb.torproject.org/torsocks.git/tree/INSTALL T -- teor ---------------------------------------------------------------------- > On 16 Dec 2018, at 01:26, Durgesh Kumar <durgesh.17bcs1179(a)abes.ac.in> wrote: > > Thanks for your reply.. > > I am intrested in TORSOCKS under usability category. > Can you please provide me a begineer guide about the project so that i can get familiar with it. > > Sorry for late reply. > > > >> On Mon 10 Dec, 2018, 6:40 AM teor, <teor(a)riseup.net> wrote: >> Hi, >> >> > On 7 Dec 2018, at 02:28, Durgesh Kumar <durgesh.17bcs1179(a)abes.ac.in> wrote: >> > >> > Dear sir/mam >> > I am durgesh kumar from ABES engineering college,ghaziabad,uttar pradesh,india. >> > >> > I am currently in 2nd year of my graduation(Btech CSE ) >> > >> > I want to contribute in some of your prestigious project. So i request you to please provide me some of your top priority project and a begineer guide. >> > >> > I hope you will concern my request. >> >> Here's a list of our projects and some project ideas: >> https://www.torproject.org/getinvolved/volunteer.html.en#Projects >> >> Let us know which ones you're interested in. >> >> T >>

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Update on Guardian Project Pluggable Transport work
by Hans-Christoph Steiner 13 Dec '18

13 Dec '18

The Guardian Project "PLUTO" project is our name for the work we're doing around Pluggable Transports. If you want to follow this work more closely, you can ask n8fr8 to add you to our semi-private PLUTO mailing list. n8fr8 is currently working on integrating PTs into Android apps in a reusable way. That work is mostly in https://github.com/guardianproject/AndroidPluggableTransports I recently did some work to port snowflake to Android. That should be useable now, but with some open issues about repeatable builds and verification that non-free libs are not linked in. That's mostly here: https://github.com/keroserene/snowflake/pull/43 Then we're doing full stack prototypes for using PTs in Android apps, based on Wikipedia, F-Droid and an RFA app. That stuff is scattered around. >From that work, uniqx (Michael Poehn) has produced a PT bridge server setup automation: https://gitlab.com/uniqx/pt-socks5-over-obfs4proxy uniqx and I are now focused on Encrypted SNI for use as a PT, so there will be some server automation around that, e.g. custom openssl/mod_ssl build included. .hc -- PGP fingerprint: EE66 20C7 136B 0D2C 456C 0A4D E9E2 8DEA 00AA 5556 https://pgp.mit.edu/pks/lookup?op=vindex&search=0xE9E28DEA00AA5556

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prob_distr.c: LogLogistic fails stochastic tests on 32-bits mingw
by George Kadianakis 13 Dec '18

13 Dec '18

Hello Riastradh, as discussed on IRC, Appveyor recently started failing the stochastic tests of LogLogistic on 32-bit builds: https://github.com/torproject/tor/pull/576 https://ci.appveyor.com/project/torproject/tor/builds/20897462 I managed to reproduce the breakage by cross-compiling Tor and running the tests with wine, using this script of ahf: https://github.com/ahf/tor-win32/ Here are my findings: The following two test cases are breaking 100% reproducibly: ok = test_stochastic_log_logistic_impl(M_E, 1e-1); ok = test_stochastic_log_logistic_impl(exp(-10), 1e-2); The breakage seems to be because of the beta parameter. In particular, it seems like the test will break with any beta <= 0.26, and will succeed with a beta >= 0.27. The space in between is still unclear ;) I haven't managed to figure out what's actually offending the test but I can reproduce this so I can do some digging if you have any ideas. FWIW, I haven't noticed any other stochastic test breakage. Cheers!

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Regarding projects and a begineer guide.
by Durgesh Kumar 10 Dec '18

10 Dec '18

Dear sir/mam I am durgesh kumar from ABES engineering college,ghaziabad,uttar pradesh,india. I am currently in 2nd year of my graduation(Btech CSE ) I want to contribute in some of your prestigious project. So i request you to please provide me some of your top priority project and a begineer guide. I hope you will concern my request.

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Network team meeting on Tuesday at 2300 UTC
by teor 10 Dec '18

10 Dec '18

Hi everyone, This week's network team meeting is on Tuesday at 2300 UTC. (If this time doesn't work for you, we'll see you the week after.) Our meetings are held on #tor-meeting on OFTC. We'll be back to our regular schedule next week, but we'll meet an hour earlier due to daylight saving time. First meeting each month: Tuesday at 2300 UTC. Other meetings each month: Mondays at 1700 UTC. T -- teor ----------------------------------------------------------------------

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