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Bridge Guards (prop#188) & Bridge ORPort Reachability Tests
by isis 30 Oct '15

30 Oct '15

Hey all, I have a working implementation of proposal #188, [0] which specifies a mechanism by which tor's (rather accidental) loose-source routing feature is utilised by Bridges in order to transparently inject a Bridge Guard into all client circuits. (See #7144. [1]) Currently, I am updating the text in proposal #188 to match my implementation, and I am trying to decide what to do about the two types of Bridge ORPort reachability testing. Here's the text I've written so far to explain the issues: (In the following, "Alice" is an OP, "Bob" is a Bridge, "Guillaume" is Bob's chosen Entry Guard, and "Charlie" is a random Middle node.) > 4.4. Bridge Reachability Testing > > Currently, a Bridge's reachability is tested both by the Bridge > itself (called "self-testing") and by the BridgeAuthority. > > 4.4.1. Bridge Reachability Self-Testing > > Before a Bridge uploads its descriptors to the BridgeAuthority, it > creates a special type of testing circuit which ends at itself: > > Bob -> Guillaume -> Charlie -> Bob > > Thus, going to all this trouble to later use loose-source routing in > order to relay Alice's traffic through Guillaume (rather than > connecting directly to Charlie, as Alice intended) is diminished by > the fact that Charlie can still passively enumerate Bridges by > waiting to be asked to connect to a node which is not > contained within the consensus. > > We could get around this option by disabling self-testing for bridges > entirely, by automatically setting "AssumeReachable 1" for all Bridge > relays… although I am not sure if this is wise. > > 4.4.2. Bridge Reachability Testing by the BridgeAuthority > > After receiving Bob's descriptors, the BridgeAuthority attempts to > connect to Bob's ORPort by making a direct TLS connection to the > Bridge's advertised ORPort. > > Should we change this behaviour? One the one hand, at least this > does not enable any random OR in the entire network to enumerate > Bridges. On the other hand, any adversary who can observe packets > from the BridgeAuthority is capable of enumeration. So, my current questions are: 1. Bridges only do reachability self-testing in order to warn their operators that the Bridge (or firewall or whatever) might be misconfigured, correct? Is there any other reason (or future reason) why self-testing is important/useful? 2. How should the self-testing be changed? 2.a. First, if there aren't any other reasons for self-testing: Is Bridge reachability self-testing actually helpful to Bridge operators in practice? Don't most Bridge operators just try to connect, as a client, to their own Bridge to see if it's working correctly? (This is what I usually do, at least…) If it's not useful to most Bridge operators, can we just disable self-testing for all Bridges? (And, should we disable it only for Bridges who are using Bridge Guards, or all of Bridges regardless?) 2.b. If it is useful to people, then the best way I can think of so far to keep it, but refactor it to be safer, would be to create a circuit like: Bridge → Guard → Middle → OtherMiddle → Guard → Bridge Clearly, that circuit is just a little bit insane… but we can't do: Bridge → Guard → Middle → Guard → Bridge because the Middle would refuse to extend back to the previous node (all ORs follow this rule). Similarly, it would be stupid to do: Bridge → Guard → Middle → OtherMiddle → Bridge because, obviously, that merely shifts the problem and accomplishes nothing. But is there something smarter I could do? 3. Should we change how the BridgeAuthority tests Bridge ORPort reachability? If so, how? 4. If I'm going to refactor all of this, are there other (future) things I should take into account? For example, if self-testing is disabled for Bridges, and, due to #7349, [2] the BridgeAuthority isn't testing reachability either, then how will the BridgeAuthority know if (any of) the Bridge's PTs are reachable? (One solution might be to, in that case, have the BridgeAuthority lie and tell BridgeDB that such Bridges were reachable, letting BridgeDB do the PT reachability testing.) Please help me brainstorm a way out of this mess! [0]: https://gitweb.torproject.org/torspec.git/tree/proposals/188-bridge-guards.… [1]: https://bugs.torproject.org/7144 [2]: https://bugs.torproject.org/7349 Best Regards, -- ♥Ⓐ isis agora lovecruft _________________________________________________________ OpenPGP: 4096R/0A6A58A14B5946ABDE18E207A3ADB67A2CDB8B35 Current Keys: https://blog.patternsinthevoid.net/isis.txt

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Tor Messenger Beta: Chat over Tor, Easily
by Sukhbir Singh 30 Oct '15

30 Oct '15

Hi, Today we are releasing a new, beta version of Tor Messenger, based on Instantbird [0], an instant messaging client developed in the Mozilla community. * What is it? Tor Messenger is a cross-platform chat program that aims to be secure by default and sends all of its traffic over Tor. It supports a wide variety of transport networks, including Jabber (XMPP), IRC, Google Talk, Facebook Chat, Twitter, Yahoo, and others; enables Off-the-Record (OTR) Messaging [1] automatically; and has an easy-to-use graphical user interface localized into multiple languages. * What it isn't... Tor Messenger builds on the networks you are familiar with, so that you can continue communicating in a way your contacts are willing and able to do. This has traditionally been in a client-server model, meaning that your metadata (specifically the relationships between contacts) can be logged by the server. However, your route to the server will be hidden because you are communicating over Tor. We are also excited about systems like Pond [2] and Ricochet [3], which try to solve this problem, and would encourage you to look at their designs and use them too. * Why Instantbird? We considered a number of messaging clients: Pidgin, Adam Langley's xmpp-client, and Instantbird. Instantbird was the pragmatic choice -- its transport protocols are written in a memory-safe language (JavaScript); it has a graphical user interface and already supports many natural languages; and it's a XUL application, which means we can leverage both the code (Tor Launcher) and in-house expertise that the Tor Project has developed working on Tor Browser with Firefox. It also has an active and vibrant software developer community that has been very responsive and understanding of our needs. The main feature it lacked was OTR support, which we have implemented [4] and hope to upstream to the main Instantbird repository for the benefit of all Instantbird (and Thunderbird) users. * Current Status Today we are releasing a beta version with which we hope to gain both usability and security related feedback. There have been three previous alpha releases to the mailing lists that have already helped smooth out some of the rougher edges. * Downloads Linux (32-bit) https://dist.torproject.org/tormessenger/0.1.0b2/tor-messenger-linux32-0.1.… Linux (64-bit) https://dist.torproject.org/tormessenger/0.1.0b2/tor-messenger-linux64-0.1.… Windows https://dist.torproject.org/tormessenger/0.1.0b2/tormessenger-install-0.1.0… OS X https://dist.torproject.org/tormessenger/0.1.0b2/TorMessenger-0.1.0b2-osx64… sha256sums https://dist.torproject.org/tormessenger/0.1.0b2/sha256sums.txt https://dist.torproject.org/tormessenger/0.1.0b2/sha256sums.txt.asc The sha256sums.txt file containing hashes of the bundles is signed with the key 0x6887935AB297B391 (fingerprint: 3A0B 3D84 3708 9613 6B84 5E82 6887 935A B297 B391). * Instructions - On Linux, extract the bundle(s) and then run: ./start-tor-messenger.desktop - On OS X, copy the Tor Messenger application from the disk image to your local disk before running it. On all platforms, Tor Messenger sets the profile folder for Firefox/Instantbird to the installation directory. - Note that as a policy, unencrypted one-to-one conversations are not allowed and your messages will not be transmitted if the person you are talking with does not have an OTR-enabled client. You can disable this option in the preferences to allow unencrypted communication but doing so is not recommended. * Source Code We are doing automated builds [5] of Tor Messenger for all platforms. The Linux builds are reproducible: anyone who builds Tor Messenger for Linux should have byte-for-byte identical binaries compared with other builds from a given source. You can build it yourself [6] and let us know if you encounter any problems or cannot match our build. The Windows and OS X builds are not completely reproducible yet but we are working on it [7]. * What's to Come Our current focus is security, robustness and user experience. We will be fixing bugs and releasing updates as appropriate, and in the future, we plan on pairing releases with Mozilla's Extended Support Release (ESR) cycle. We have some ideas on where to take Tor Messenger but we would like to hear what you have to say. Some possibilities include: - Reproducible builds for Windows and OS X (#10942) - Sandboxing (#10943) - Automatic updates (#14388) - Improved Tor support (#10950) - OTR over Twitter DMs (#13312) - Produce (and distribute) internationalized builds (#10945) - Secure multi-party communication (np1sec) [8] - Encrypted file-transfers - Usability study * How To Help Give it a try and provide feedback, requests, and file bugs [9] (choose the "Tor Messenger" component). If you are a developer, help us close all our tickets [10] or help us review our design doc [11]. As always, we are idling on IRC in #tor-dev (OFTC) (nicks: arlolra; boklm; sukhe) and subscribed to the tor-talk/dev mailing lists. Please note that this release is for users who would like to help us with testing the product but at the same time who also understand the risks involved in using beta software. Thanks and we hope you enjoy Tor Messenger! [0] - http://instantbird.com [1] - https://otr.cypherpunks.ca [2] - https://pond.imperialviolet.org [3] - https://ricochet.im [4] - https://github.com/arlolra/ctypes-otr [5] - https://gitweb.torproject.org/tor-messenger-build.git [6] - https://gitweb.torproject.org/tor-messenger-build.git/tree/README [7] - https://trac.torproject.org/projects/tor/ticket/10942 [8] - https://github.com/equalitie/np1sec [9] - https://trac.torproject.org/projects/tor/newticket [10] - https://trac.torproject.org/projects/tor/query?status=!closed&component=Tor… [11] - https://trac.torproject.org/projects/tor/wiki/doc/TorMessenger/DesignDoc

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[Applications Team] First meeting next Tuesday 19:00 UTC
by Georg Koppen 29 Oct '15

29 Oct '15

Hi, just a reminder that the applications team is starting the monthly meetings next week on Tuesday, November 3 at 19:00 UTC[0] in #tor-project on irc.oftc.net. The proposed topic is still talking about UX/internationalization issues. If there are other things worth discussing we can easily amend the agenda at the beginning of the meeting. See you there, Georg [0] Originally I had written "18:00 UTC" but I forgot to take the end of the summer time into account.

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Re: [tor-dev] Pluggable Transports v1 spec rewrite.
by Nathan Freitas 29 Oct '15

29 Oct '15

On Thu, Oct 29, 2015, at 09:19 AM, Yawning Angel wrote: > Hello all, > > In an attempt to make Pluggable Transports more accessible to other > people, and to have a spec that is more applicable and useful to other > projects that seek to use Pluggable Transports for circumvention, I have > drafted a re-write of the spec. > > This is not intended to alter existing behavior, but instead make it > clear that the whole "Pluggable Transports" thing isn't just for Tor. > > Unless people have serious objections, this will replace the existing > PT spec, to serve as a stop-gap while the next revision of the PT spec > (that does alter behavior) is being drafted/implemented. > Any small or big changes to highlight that push us to the more accessible goal?

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Re: [tor-dev] Pluggable Transports v1 spec rewrite.
by Hugo Maxwell Connery 29 Oct '15

29 Oct '15

Hi, A commendable effort. It is both deserved and pleasant that Tor hold the "gold standard" for a low latency, privacy enhancing, distributed, collaborative network. A perhaps more crowning achievement could be the fostering of a diverse ecosystem of related technologies. This effort continues to signal the Tor community's belief in open, free(dom), collaboration in the space. Hats off ! Hugo ________________________________________ Date: Thu, 29 Oct 2015 13:19:01 +0000 From: Yawning Angel <yawning(a)schwanenlied.me> To: tor-dev(a)lists.torproject.org Subject: [tor-dev] Pluggable Transports v1 spec rewrite. Message-ID: <20151029131901.3bbe0a20(a)schwanenlied.me> Content-Type: text/plain; charset="us-ascii" Hello all, In an attempt to make Pluggable Transports more accessible to other people, and to have a spec that is more applicable and useful to other projects that seek to use Pluggable Transports for circumvention, I have drafted a re-write of the spec. This is not intended to alter existing behavior, but instead make it clear that the whole "Pluggable Transports" thing isn't just for Tor. Unless people have serious objections, this will replace the existing PT spec, to serve as a stop-gap while the next revision of the PT spec (that does alter behavior) is being drafted/implemented. Regards, -- Yawning Angel

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Reminders: this week's Tor dev meeting is still at 1330 UTC today
by Nick Mathewson 28 Oct '15

28 Oct '15

Hi! Reminder 1: There is a weekly meeting where we talk about development progress on the program "tor". Reminder 2: It has been at 1330 UTC; it is still at 1330 UTC for this week. (Remember, some of the world has made DST changes, but not all of the world.) Reminder 3: It will be at a different time (TBD) next week. Thanks, all! -- Nick

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TB 5.0.3 for OpenBSD released
by attila 28 Oct '15

28 Oct '15

The Tor BSD Diversity Project (TDP) is proud to announce the release of Tor Browser (TB) version 5.0.3 for OpenBSD. TDP (https://torbsd.github.io) is an effort to extend the use of the BSD Unixes into the Tor ecosystem, from the desktop to the network. The 5.0.3 release is the sixth release of the Tor Browser from TDP. To install TB for OpenBSD, please see http://mirrors.nycbug.org/pub/snapshots/packages/amd64/README if you are running OpenBSD -current on amd64. TDP is focused on diversifying the Tor network, with TB being the flagship project. Additional efforts are made to increase the number of *BSD relays on the Tor ntwork. Since its launch in March 2015, TDP has made significant contributions. In addition to the TB releases, both BSDCan and BSDCon Brasil featured TDP-focused meetings. In early October, the TDP focused presentation (http://www.queair.net/br-pres) prompted a significant increase in Tor relays in Brazil. Before the presentation, there were around 22 Tor relays, all of which were Linux in addition to two Windows nodes. In the weeks after the presentation, several new *BSD Tor relays appeared, accounting for up to 35% of bandwidth provided by new Tor relays in Brazil. Finally, TDP is working to convince BSD-using businesses to follow Mozilla's December 2014 example to run Tor relays. At this point, New York Internet has commited to running two high-bandwidth relays, one FreeBSD and the other OpenBSD, at its facility in Bridgewater, New Jersey. TDP's source code repository resides at http://github.com/torbsd. If you want to build the ports from source under OpenBSD-current the current tarball is available at http://bits.haqistan.net/~attila/tbb.tgz Feel free to bug me if you need help (contact infos on my home page: http://trac.haqistan.net/~attila) TDP is seeking funding to continue and extend its efforts. Please contact us if interested in assisting TDP, allowing us to dedicate more time to the project. Pax, -A -- http://trac.haqistan.net | attila(a)stalphonsos.com | 0xE6CC1EDB

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Feedback on CollecTor web redesign
by Karsten Loesing 28 Oct '15

28 Oct '15

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi devs, I just finished a redesign of the CollecTor website and would appreciate your feedback: https://metrics.torproject.org/index2.html For reference, the old CollecTor website is still available here: https://metrics.torproject.org/index.html https://metrics.torproject.org/formats.html Let me add that I'm not a web designer, and let me prove that statement by telling you that <i>all</i> HTML on that website was written using vim. I'm more than happy to accept patches or suggestions, though I'll likely ask you to explain them to me. Thanks! All the best, Karsten -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: GPGTools - http://gpgtools.org iQEcBAEBAgAGBQJWJpaaAAoJEJD5dJfVqbCr8/YIAIimH7j5Z2qr7OwfhBrH20MJ fNoBEdFBjSveWTYsB/77yZx1mEtDTXI/FCCQM5AURmE82SUJQ1Ocumn+J2mVgdmh hobxFrQBnsSWdK0qDtyNc7U5oDX7P6ruoBdfwBtFppXpp/VHkFsU0TIiMxcqGcUH yuHzRlaSIUpOXzaFl4STeEM9zmFqaR8+qayteWrWQpLMHf3SOksXKcr14+8CZmsl C7YopnoLqglo0dQA9FjM3U+w9MnEoHHskN4Yl4ZkQFGYPziqNRFTHmvCoKEMUz3u 0o1Emcmxc9jaZbyBU8Vbh474uEXM2ZtWSlMUt9M3dBRkIyuHy6lcBMS5q3i2wXc= =hHc4 -----END PGP SIGNATURE-----

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[Metrics Team] Metrics Team mailing list and Metrics Team wiki page
by Karsten Loesing 28 Oct '15

28 Oct '15

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello Metrics Team members, hello devs, the Metrics Team now has a team wiki page and a team mailing list: https://trac.torproject.org/projects/tor/wiki/org/teams/MetricsTeam https://lists.torproject.org/cgi-bin/mailman/listinfo/metrics-team As described on the wiki page, the mailing list "is public in the sense that anyone can subscribe and read archives. But it's moderated on first post, meaning that your first post will be reviewed to make sure it's not spam and on topic and all further posts will go directly to the list. Feel free to subscribe and just listen if you want, and feel free to post if you have a question that you think is on topic." Everyone here should feel free to subscribe if they're interested in Metrics Team discussions. We should still move all discussions that are interesting to more people in Tor than just the Metrics Team to the tor-dev@ mailing list. Let's see how this works out. Note that future announcements, including meeting reminders, will go to the metrics-team@ list. (FWIW, there will be NO meeting tomorrow but next week.) All the best, Karsten -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: GPGTools - http://gpgtools.org iQEcBAEBAgAGBQJWMIJHAAoJEJD5dJfVqbCrpZcIALEmgZuRxflQHm5mTYhevYAn T5+tbclKDjjo3hfVmMdQOTtJFkLzkoO/jX4zTTuRiN3O+3jtcAcAtQ/xLLxA/wP3 wMJ76aRe6GIJ7lfO1+GQGKQCO1wO8lWDrY5vEr3yARWZB2KiSaFfWofe7nHq1G2V HjlUz+JeuAEWsLTxlkq+g3nrLpGtsEip3h85NA7pIicik35D1/W7S3jy/L1UKKO9 noH2QUBbQpfO0oW+Tjq+aYLO7hp98ThNO6JFDVM5tVOoDsxAnlMWtJQihDAlK7b0 5+sH6ixYBuvOOvoOCRl/3DJqTuQO+IpCcAGI7qLJOpMCIrAcsq0Lwaz5tJrieSk= =8Zhk -----END PGP SIGNATURE-----

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1-1-1 task exchange meeting on Thursday, Oct 29, 15:00 UTC in #tor-dev
by Karsten Loesing 28 Oct '15

28 Oct '15

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello devs, we'll have another 1-1-1 task exchange meeting on Thursday, October 29, 2015, 15:00 UTC in #tor-dev https://www.timeanddate.com/worldclock/fixedtime.html?iso=20151029T15 Note how this may be a different time in your timezone based on the insight that we have all saved enough daylight for the year. Quick reminder: The idea of the 1-1-1 task exchange meeting is that participants get 1 minute to describe a task that would take somebody else roughly 1 hour and that they will do within 1 week. It could be to review a document, write some analysis code, fix a small bug, and so on. It's best to come prepared with a task or two to get the most out of this. In a perfect world people would give one task for each task they take, but that is not required. https://trac.torproject.org/projects/tor/wiki/doc/1-1-1-task-exchange Talk to you tomorrow. All the best, Karsten -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: GPGTools - http://gpgtools.org iQEcBAEBAgAGBQJWMHz2AAoJEJD5dJfVqbCr5e8H/3hPCDeEmrXuzEX4UZXxHoa+ RAsl5RN/Q2XFXMFayxno5BaGRBclusCDlbadOHcBcJeaZmETrfLmV1pN4OJA0yO9 RpNMcujl5VdOJSNcw5zxXn+QnHQPEqOUX4wFXuj/1BoAVRaek43IuqPTDTECNMRh 92vMaSJIQWxtudk5h0qhzB+DAEJSyTAU3gHH1yFecOITT2Nr69h6//WJIVn83rKW ViwLkQ4CoRfpp3aXyNRmMBEFj08bx09EAhI7bEkXYKf5oug5S/ah/YmHkHtfq+2D L9iz6vV/DdgXja/kcjMkakUvRAcSZPdNmmJwAqym2jCk+8FN9MsLW1ktL/R12xQ= =wU4R -----END PGP SIGNATURE-----

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