- tor-dev - lists.torproject.org

HOWTO use Lantern as a pluggable transport
by David Fifield 03 Mar '14

03 Mar '14

I met today with some developers of Lantern (https://getlantern.org/, https://github.com/getlantern/lantern) Lantern acts as an HTTP proxy and proxies your traffic through trusted friends. We found that we had the pieces necessary to make Lantern a pluggable transport of Tor; that is, use Lantern as a transport for Tor traffic where Tor is blocked but Lantern is not. Here's what we did to make it work. Lantern is an HTTP proxy. As luck would have it, I have lately been working on a transport that encodes data in HTTP requests (https://lists.torproject.org/pipermail/tor-dev/2014-January/006159.html) meek was designed for a completely different purpose--tunneling traffic through App Engine--but it turned out to be almost perfect for the Lantern case, too. The only thing it was missing was support for an upstream HTTP proxy. We used the attached patch to add proxy support and hardcode Lantern's proxy port of 8787. meek normally connects to App Engine, and uses a TLS trick to make it look like it is going to www.google.com. The meek-client program connects App Engine, and then App Engine forwards traffic to the bridge. The configuration looks like this: ClientTransportPlugin meek exec meek-client --url=https://meek-reflect.appspot.com/ --front=www.google.com With Lantern it's a bit different. We don't need to do the TLS fronting trick because we use Lantern as an opaque HTTP-carrying transport. Instead of going through App Engine, we tell meek-client to make requests directly to the Tor bridge (where "directly" means "directly through the Lantern proxy"). ClientTransportPlugin meek exec meek-client --url=http://tor1.bamsoftware.com:7002/ And that's all. We downloaded one of the experimental meek bundles from https://people.torproject.org/~dcf/pt-bundle/3.5.2.1-meek-1/, copied in the patched meek-client binary, and made the above change to the ClientTransportPlugin line in torrc-defaults. With Lantern already running and configured on the same machine, we started tor and it bootstrapped. I'll take the proxy patch and modify it so that the proxy address is not hardcoded, so that you can configure it from the command line. It could also be useful for users who need pluggable transports but are stuck behind an HTTP proxy. Special thanks to Ox from Lantern who pair-programmed this with me. David Fifield

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How to test Linux capabilities & pluggable transports
by George Kadianakis 02 Mar '14

02 Mar '14

Hello David, the other day you asked for a quick way to test Linux capabilities and pluggable transports (to combine #7875 and #8195). What you probably want to do, is write a small script that prints the active Linux capabilities, spawn it as a pluggable transport, and check its output to see if the capabilities we wanted it to inherit are active. Here is an example of how to do this. I'm using a python script here, but you can do whatever you want. Use this torrc (only the final line really matters): """ SocksPort 0 ORPort 6666 BridgeRelay 1 PublishServerDescriptor 0 ServerTransportPlugin cap exec /usr/bin/python /home/user/cap.py """ where cap.py can be: """ #!/usr/bin/python print "test test" """ If you start up tor with that torrc ($ ./src/or/tor -f my_torrc), you will get: """ Mar 02 12:54:43.000 [notice] Unknown line received by managed proxy (test test). """ in your Tor output. You can use these lines to debug your capabilities. Otherwise, you can log to a file and read that file instead. Of course in cap.py, you will probably want to print your capabilities, or bind to a port < 1024, or something like that. Feel free to ask any questions you have.

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Call for testing/review: obfsclient-0.0.1rc1
by Yawning Angel 02 Mar '14

02 Mar '14

Hello all, Due to a moment of surprising productivity, I have a release candidate of obfsclient available now. For those of you that missed the last thread regarding this, it is a C++11 client implementation of obfs2, obfs3, and ScrambleSuit that works as a drop in replacement for obfsproxy. Notable changes since the last time I posted: * ScrambleSuit code is now up to spec. * Packet length and Inter-packet Arrival Times are randomized. * Session Ticket Handshake is supported. * obfsclient will give up on handshaking after 60 seconds. * Needed because obfsproxy servers do not close the connection for certain protocols. * SIGINT is hooked and handled per the pt spec. * Some dumb bugs were fixed. Places where obfsclient behaves differently from obfsproxy: * Current production obfsproxy releases disable Scramblesuit IAT obfuscation. obfsclient also uses slightly different logic for sending with it enabled. (May change for final release) * WELL512 is used instead of MT for the ScrambleSuit packet length obfuscation. * obfsclient gives up when the handshaking stalls. * The SOCKS5 response is sent post obfuscation protocol handshake instead of before. * obfsclient uses SOCKS5 instead of SOCKS4. * The ScrambleSuit Session Ticket store is a plain text file. Things that are not bugs: * ScrambleSuit requires the client side tor to be 0.2.5.x. * The code will not build if the compiler is from the stone age. To what I assume will be a sigh of relief from Fabian, I tested on FreeBSD as well this time. The systems used for testing are in the release notes. Where: https://github.com/Yawning/obfsclient/releases/tag/v0.0.1-rc1 Thanks in advance, -- Yawning Angel

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Damian's Status Report - February 2014
by Damian Johnson 02 Mar '14

02 Mar '14

It was great meeting everyone in Reykjavík! February largely went toward GSoC prep. Thanks to everybody that sent me project ideas! https://blog.torproject.org/blog/tor-google-summer-code-2014 This left a lot less time than I'd like for coding. The only noteworthy changes this month were... * Added a new 'stem.util.test_tools' module for easily running Pyflakes and PEP8 checks... https://gitweb.torproject.org/stem.git/blob/HEAD:/stem/util/test_tools.py Stem, ExitMap, and arm all do these checks as part of their tests so this let them shed quite a bit of boilerplate. Want these checks for your own project? It's easy, so give it a try! https://gitweb.torproject.org/user/atagar/exitmap.git/blob/HEAD:/run_tests.… * Stem tutorial example for checking the Tor exits you're using for your connections... https://stem.torproject.org/tutorials/to_russia_with_love.html#determine-th… * Couple new Controller methods for checking where Tor is listening for connections of a given type... https://stem.torproject.org/api/control.html#stem.control.Listener https://stem.torproject.org/api/control.html#stem.control.Controller.get_po… https://stem.torproject.org/api/control.html#stem.control.Controller.get_li… >>> for listener_type in stem.control.Listener: ... ports = map(str, controller.get_ports(listener_type)) ... print "%s ports: %s" % (listener_type, ', '.join(ports)) ... OR ports: DIR ports: SOCKS ports: 9050 TRANS ports: NATD ports: DNS ports: CONTROL ports: 2779 * Gave Sphinx's aafig module a try to see if it could improve our API overviews... https://www.atagar.com/transfer/stem/overview_before.png https://www.atagar.com/transfer/stem/overview_after.png In the end I decided against it since this doesn't add much, and it causes us to render the overview as a svg (so users can't copy/paste function names). * Sent Philipp some improvements for ExitMap... https://lists.torproject.org/pipermail/tor-dev/2014-February/006162.html Cheers! -Damian

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[weather-rewrite] Update on hourly-script
by Oliver Baumann 01 Mar '14

01 Mar '14

Hi Team, please see [1] for the current status of the hourly bandwidth script and feel free to comment on any improvements! Currently it's just a script calling several functions and performing some work 'off hand'. Once we move into integrating with a webapp, refactoring should make this nice and object-oriented :) Have a nice weekend and happy hacking, Oliver [1] https://trac.torproject.org/projects/tor/ticket/10697

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Patch to remove goto from sandbox.c
by Hartmut Prochaska 01 Mar '14

01 Mar '14

-----BEGIN PGP SIGNED MESSAGE----- Hash: RIPEMD160 Hi, I changed a function in sandbox.c to not use a goto statement. I didn't understood what use it had. Attached the patch file. I did the usual tests and didn't found any error at first and second glance. Please consider to test it yourself and if fit include it into production. best regards Hartmut PS: I try to remove some more gotos, if this patch is ok. - -- Ideas are the only things that can change the world. The rest is details. -- Scott Adams https://netzpolitik.org/2013/anleitung-so-verschlusselt-ihr-eure-e-mails-mi… new Key ID since 26.07.13: 0xD8C361E6 Fingerprint: E5B3 302B 1BE1 D0B4 F190 E739 A365 60A9 D8C3 61E6 -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBAwAGBQJTEgcdAAoJEKNlYKnYw2Hm9CwP/37Jijgz4By5Au/xkzWUiUWr gRPNTswPZNKhZotgWNYvxQ3SJjhI0pKdFZicX3XUIMUCVJ5wFNT/4Edq3QdDsNGk CorJ+J/UcuzpCQomqJ+zOj6Av+pNSe6/Nbpf8NOgNjAhF1fsqQNQb2/IuSwmqppy YbVl8noNLk6cEb283xLWjwIVNPPTi1Nj0jDFh25ZVxGYcICkDUG6jDjhHNCAZJgG mQEbvq6kBNeh5qX7KPmxhI7fSBh6kTFTLWxLAbYXJQFugqf1ho7T/ULFNOEFDu3e edijtSfk1ysJ0bd9UoUfkD5cJ4fralgIH8mXhlntOxJpwL640g7Gla/bIpsiwrPW XnBGM+qUrhd1HMLZVyVGBAysz+AIOFGYBSC4ZBGG4r2hDStakFHUJ5pNLJYY6EbA NAh03yf8XtPnCM17dojBXvQK1KEXsl0St4ChcERp0uq1v/7d3MLNtM+h1iGhFacT YQyUuZvbvaRoQp7bQUdLjnlRZHhGySwQnzU1T1hY3dxp/182GAGy/SxaWdG+NNsi mVcxLJedzxm4Fx+cARPHLYDU3xPM7EPYSa81eOEUrniVJYx1LiacDSoVRlhfRQiU +8mEs/eaOJJzaooSq/msYiTfFRh4bAu999nk+VHUo+9m9cjjp0sfzPSGNaBkg7dP BLKg6P6uM8sDlOd3yZ4b =g1L7 -----END PGP SIGNATURE-----

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tor2web proposal: comments appreciated before I commit this
by Virgil Griffith 01 Mar '14

01 Mar '14

Filename: ???-quickening-tor2webmode.txt Title: Making Tor2Web mode faster Author: Virgil Griffith, Fabio Pietrosanti, Giovanni Pellerano Created: 2014-02-23 Status: Open 1. Introduction While chatting with the Tor archons at the winter meeting, two speed optimizations for tor2web mode [1] were put forward. This proposal specifies concretizes these two optimizations. As with the current tor2web mode, this quickened tor2web mode negates any client anonymity. 2. Tor2web optimizations 2.1) self-rendezvous In the current tor2web mode, the client establishes a 0-hop circuit (direct connection) to a chosen rendezvous point. We propose that, alternatively, the client set *itself* as the rendezvous point. This coincides with ticket #9685 [2]. 2.2) direct-introduction Identical to the non-tor2web mode, in the current tor2web mode, the client establishes a 3-hop circuit to the introduction point. We propose that, alternatively, the client build a 1-hop (or 0-hop?) circuit to the introduction point. 4. References [1] Tor2web mode: https://trac.torproject.org/projects/tor/ticket/2553 [2] Self-rendezvous: https://trac.torproject.org/projects/tor/ticket/9685

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TIMB - how may I contribute?
by CIURANA EUGENE (pr3d4t0r) 28 Feb '14

28 Feb '14

Greetings! 30 years of experience; proficient in Java, C, Python, Objective-C, Smalltalk, and R, with a pile of other languages too for minor or one-time projects. Work primarily with OS X and Linux. Familiar with most CLI Linux project management tool, not familiar at all with Gnome/KDE/etc. Coding, testing, translation, and server resources contributor to a wide range of open source projects like Jetty, Mule, Vim, WeeChat, Linux (looooong time ago; 1998), iPhone jailbreaks, DAViCal, etc. In the real world I specialize in designing and building scalable, highly available systems (including gathering and managing the team to build them). Rolling my sleeves up, ready to help. Cheers! E -- pr3d4t0r @ #tor, #tails, #tor-dev irc.oftc.net

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Tor proposal status updates: interesting! (Feb 2014)
by Nick Mathewson 28 Feb '14

28 Feb '14

Hi, all! This list of open Tor proposals is based on one I sent out back in December[0], based on the one I did in November[1] based on the one I did in June of 2012[2], based on the one I did in May[3] of 2011. Future versions of this document will be maintained in the torspec repository as "proposals/proposal-status.txt". I'll still send them to tor-dev periodically. If you're looking for something to review, think about, or comment on: Review 212 (using older consensuses) or 215 (obsoleting consensus methods) if you understand the directory system even a little bit; they are quite simple. Review 219 if you're a DNS geek, or you'd like Tor to work better with more DNS types. Review 220 (ed25519 identity keys) and 228 (cross-certification) if you like designing signature things, if you have good ideas about future-proofing key type migration, or if you care about making Tor servers' identity keys stronger. Review 223 (ACE handshake) if you're a cryptographer, or a cryptography implementer, and you'd like an even faster replacement for the ntor handshake. Review 224 if you want to look through a big, complex protocol with a lot of pieces. Also review it if you care about hidden services and making them better. Review 226 if you're interested in bridgedb development. Review something else if you want to take a possibly good idea that needs more momentum and promote it, fix it up, or finally kill it off. I note in passing that many of the proposals below seem stalled, perhaps permanently: some because we don't know how to answer their open questions, others because we're not sure if they're a good idea, others because they don't seem implementable yet. Is that the best way to characterize it? Should we have a new "stalled" proposal status or something? Should we have a "rejected-pending-revision" status that we use effectively for everything that doesn't seem likely to get revised or implemented any time soon? Other suggestions would be welcome. Finally: if you've sent something to tor-dev or to me that should have a proposal number, but doesn't have one yet, please ping me again to remind me! [0] https://lists.torproject.org/pipermail/tor-dev/2013-December/005957.html [1] https://lists.torproject.org/pipermail/tor-dev/2013-November/005798.html [2] https://lists.torproject.org/pipermail/tor-dev/2012-June/003641.html [3] https://lists.torproject.org/pipermail/tor-dev/2011-May/002637.html **NOTE**: The dates after each paragraph indicate when I last revised the paragraph. 127 Relaying dirport requests to Tor download site / website The idea here was to make it easier to fetch and learn about Tor by making it easy for relays to automatically act as proxies to the Tor website. It needs more discussion, and there are some significant details to work out. It's not at all clear whether this is actually a good idea or not. Probably, there are better choices when it comes to distributing software and updates. (11/2013) 131 Help users to verify they are using Tor [NEEDS-REVISION] This one is not a crazy idea, but I marked it as needs-revision since it doesn't seem to work so well with our current designs. It seems mostly superseded by proposal 211. (11/2013) 132 A Tor Web Service For Verifying Correct Browser Configuration This proposal was meant to give users a way to see if their browser and privoxy (yes, it was a while ago) are correctly configured by running a local webserver on 127.0.0.1. I'm not sure the status here. Generally, I'm skeptical of designs that run webservers on localhost, since they become a target for cross-site attacks. (11/2013) 133 Incorporate Unreachable ORs into the Tor Network This proposal had an idea for letting ORs that can only make outgoing connections still relay data usefully in the network. It's something we should keep in mind, and it's a pretty neat idea, but it radically changes the network topology. Anybody who wants to analyze new network topologies should definitely have a look. (5/2011) 140 Provide diffs between consensuses This proposal describes a way to transmit less directory traffic by sending only differences between consensuses, rather than the consensuses themselves. It is mainly languishing for lack of an appropriately licensed, well-written, very small, pure-C implementation of the "diff" and "patch" algorithms. (The good diffs seem to be GPL (which we can't use without changing Tor's license), or spaghetti code, or not easily usable as a library, or not written in C, or very large, or some combination of those.) (5/2011) 141 Download server descriptors on demand The idea of this proposal was for clients to only download the consensus, and later ask nodes for their own server descriptors while building the circuit through them. It would make each circuit more time-consuming to build, but make bootstrapping much cheaper. Microdescriptors obsolete a lot of this proposal, and present some difficulties in using in a way compatible with it. (6/2012) 143 Improvements of Distributed Storage for Tor Hidden Service Descriptors Here's a proposal from Karsten about making the hidden service DHT more reliable and secure to use. It could use more discussion and analysis. We should look into it as part of efforts to improve designs for the next generation of hidden services. One problem with the analysis here, though, is that it assumes a fixed set of servers that doesn't change. One reason that we upload to N servers at each chosen point in the ring is that the hidden service host and the hidden service client may have different views of which servers exist. We need to re-do the analysis with some fraction of recent consensuses. (11/2013) 144 Increase the diversity of circuits by detecting nodes belonging the same provider This is a version of the good idea, "Let's do routing in a way that tries to keep from routing traffic through the same provider too much!" There are complex issues here that the proposal doesn't completely address, but I think it might be a fine idea for somebody to see how much more we know now than we did in 2008, particularly in light of the relevant paper(s) by Matt Edmann and Paul Syverson. (5/2011) 145 Separate "suitable as a guard" from "suitable as a new guard" [NEEDS-RESEARCH] Currently, the Guard flag means both "You can use this node as a guard if you need to pick a new guard" and "If this node is currently your guard, you can keep using it as a guard." This proposal tries to separate these two concepts, so that clients can stop picking a router once it is full of existing clients using it as a guard, but the clients currently on it won't all drop it. It's not clear whether this has anonymity issues, and it's not clear whether the imagined performance gains are actually worthwhile. (5/2011) 156 Tracking blocked ports on the client side This proposal provides a way for clients to learn which ports they are (and aren't) able to connect to, and connect to the ones that work. It comes with a patch, too. It also lets routers track ports that _they_ can't connect to. I'm a little unconvinced that this will help a great deal: most clients that have some ports blocked will need bridges, not just restriction to a smaller set of ports. This could be good behind restrictive firewalls, though. The router-side part is a little iffy: routers that can't connect to each other violate one of our network topology assumptions, and even if we do want to track failed router->router connections, the routers need to be sure that they aren't fooled into trying to connect repeatedly to a series of nonexistent addresses in an attempt to make them believe that (say) they can't reach port 443. This one is a paradigmatic "open" proposal: it needs more discussion. The patch probably also needs to be ported to 0.2.3.x; it touches some code that has changed. (5/2011) 159 Exit Scanning This is an overview of SoaT, with some ideas for how to integrate it into Tor. (5/2011) 164 Reporting the status of server votes This proposal explains a way for authorities to provide a slightly more verbose document that relay operators can use to diagnose reasons that their router was or was not listed in the consensus. These documents would be like slightly more verbose versions of the authorities' votes, and would explain *why* the authority voted as it did. It wouldn't be too hard to implement, and would be a fine project for somebody who wants to get to know the directory code. (5/2011) 165 Easy migration for voting authority sets This is a design for how to change the set of authorities without having a flag day where the authority operators all reconfigure their authorities at once. It needs more discussion. One difficulty here is that we aren't talking much about changing the set of authorities, but that may be a chicken-and-egg issue, since changing the set is so onerous. If anybody is interested, it would be great to move the discussion ahead here. (5/2011) 168 Reduce default circuit window This proposal reduces the default window for circuit sendme cells. I think it's implemented (or mostly implemented) in 0.2.1.20? If so, we should make sure that tor-spec.txt is updated and close it. (11/2013) 172 GETINFO controller option for circuit information 173 GETINFO Option Expansion These would help controllers (particularly arm) provide more useful information about a running Tor process. They're accepted and some parts of 173 are even implemented: somebody just needs to implement the rest. (5/2011) 175 Automatically promoting Tor clients to nodes Here's Steven's proposal for adding a mode between "client mode" and "relay mode" for "self-test to see if you would be a good relay, and if so become one." It didn't get enough attention when it was posted to the list; more people should review it. (5/2011) 177 Abstaining from votes on individual flags Here's my proposal for letting authorities have opinions about some (flag,router) combinations without voting on whether _every_ router should have that flag. It's simple, and I think it's basically right. With more discussion and review, somebody could/should build it, I think. (11/2013) 182 Credit Bucket This proposal suggests an alternative approach to our current token-bucket based rate-limiting, that promises better performance, less buffering insanity, and a possible end to double-gating issues. (6/2012) 185 Directory caches without DirPort The old HTTP directory port feature is no longer used by clients and relays under most circumstances. The proposal explains how we can get rid of the requirement that non-bridge directories have an open directory port. (6/2012) 188 Bridge Guards and other anti-enumeration defenses This proposal suggests some ways to make it harder for a relay on the Tor network to enumerate a list of Tor bridges. Worth investigating and possibly implementing. (6/2012) 189 AUTHORIZE and AUTHORIZED cells 190 Bridge Client Authorization Based on a Shared Secret [NEEDS-REVISION] 191 Bridge Detection Resistance against MITM-capable Adversaries Proposal 187 reserved the AUTHORIZE cell type; these proposals suggests how it could work to try to make it harder to probe for Tor bridges. They need more alternatives and attention, and possibly some revision and analysis. Number 190 needs revision, since its protocol isn't actually so great. (11/2013) 192 Automatically retrieve and store information about bridges This proposal gives an enhancement to the bridge information protocol, where clients remember more things about bridges, and are able to update what they know about them over time. Could help a lot with bridge churn. (6/2012) 194 Mnemonic .onion URLs Here's one of several competing "let's make .onion URLs human-usable" proposals. This one makes sentences using a fixed map. This kind of approach is likely to obsoleted if we go ahead with current plans for hidden services that would make .onion addresses much longer, though. (11/2013) 195 TLS certificate normalization for Tor 0.2.4.x Here's the followup to proposal 179, containing all the parts of proposal 179 that didn't get built, and a couple of other tricks besides to try to make Tor's default protocol less detectable. I'm pretty psyched about the part where we let relays drop in any any self-signed or CA-issued certificate that they like. Some of this is done in ticket #7145; we should decide, however, how much we want to push towards normalizing the main Tor protocol. (11/2013) 196 Extended ORPort and TransportControlPort Here are some remaining pieces of the pluggable transport protocol that give Tor finer control over the behavior of its transports. Much of this is implemented in 0.2.5 now; we should figure out what's left, and whether we want to build that. (11/2013) 197 Message-based Inter-Controller IPC Channel This proposal is for an architectural enhancement in Tor deployments, where Tor coordinates communications between the various programs (Vidalia, TorBrowser, etc) that are using it. (6/2012) 199 Integration of BridgeFinder and BridgeFinderHelper Here's a proposal for how Tor can integrate with a client program that finds bridges for it. I've seen some work being done on things called "BridgeFinder"; I don't know what the status of the current proposal is, though. (11/2013) 201 Make bridges report statistics on daily v3 network status requests Here's a proposal for bridges to better estimate the number of bridge users. (6/2012) 202 Two improved relay encryption protocols for Tor cells Here's a sketch of the two broad classes of alternatives for improving how relay encryption works. Right now, progress on this proposal is stalled waiting for the ideal wide-block construction to come along the line. (11/2013) 203 Avoiding censorship by impersonating an HTTPS server This one is a design for making a bridge that acts like an HTTPS server (by *being* an HTTPS server) until the user proves they know it's a bridge. (11/2013) 209 Tuning the Parameters for the Path Bias Defense In this proposal, Mike discusses alternative parameters for getting better result out of the path-bias-attack detection code. (11/2013) 210 Faster Headless Consensus Bootstrapping This proposal suggests that we get our initial consensus by launching multiple connections in parallel, and fetching the consensus from whichever one completes. In my opinion, that would be a fine idea when we're fetching our initial consensus from non-Authority DirSources, but we shouldnt' do anything to increase the load on authorities. (11/2013) 211 Internal Mapaddress for Tor Configuration Testing Here, the idea is to serve an XML document over HTTP that would let the know when it's using Tor. The XML document would be returned when you make a request over Tor for a magic address in 127.0.0.0/8. I think we need to do _something_to solve this problem, but I'm not thrilled with the idea of having any more magical addresses like this; we got rid of .noconnect for a reason, after all. (11/2013) 212 Increase Acceptable Consensus Age This proposal suggests that we increase the maximum age of a consensus that clients are willing to use when they can't find a new one, in order to make the network robust for longer against a failure to reach consensus. In my opinion, we should do that. If I recall correctly, there was some tor-dev discussion on this one that should get incorporated into a final, implementable version. (11/2013) 215 Let the minimum consensus method change with time This proposal describes how we can raise the minimum allowable consensus method that all authorities must support, since the ancient "consensus method 1" would not actually be viable to keep the Tor network running. We should do this; see ticket #10163. (11/2013) 219 Support for full DNS and DNSSEC resolution in Tor Here's a design to allow Tor to support a full range of DNS request types. It probably isn't adequate on its to make DNSSEC work realistically, since naive DNSSEC requires many round trips that wouldn't be practical over Tor. It has a ton of inline discussion that needs to get resolved before this is buildable. One thing to consider here is whether we can get the server-side done with reasonable confidence, and figure out the client side once more servers have upgraded. (12/2013) 220 Migrate server identity keys to Ed25519 This one is a design to migrate server identity keys to Ed25519 for improved security margin. It needs more analysis of long-term migration to other signing key types -- what do we do if we want to add support for EdDSA over Curve3617 or something? Can we make it easier than this? And it also needs analysis to make sure it enables us to eventually drop RSA1024 keys entirely. I've started building this, though, so we'd better figure out out fairly soon. Other proposals, like 224, depend on this one. (2/2014) 223 Ace: Improved circuit-creation key exchange Here's an interesting one. It proposes a replacement for the ntor handshake, using the multi-exponentiation optimization, to run a bit faster at an equivalent security level. Assuming that more cryptographers like the security proof, and that the ntor handshake winds up being critical-path in profiles as more clients upgrade to 0.2.4 or 0.2.5, this is something we should consider. (12/2013) 224 Next-Generation Hidden Services in Tor This proposal outlines a more or less completely revised version of the Tor hidden services protocol, improved to accomodate better cryptography, better scalability, and defenses for several attacks we'd never considered when we did the original design. Some parts of this one are clearly right; some (like scalability) are entirely unwritten. This proposal needs a lot of attention and improvements to get it done right. I hope to implement this over the course of 2014. (12/2013) 225 Strawman proposal: commit-and-reveal shared rng Proposal 224's solutions for bug #8244 require that authorities regularly agree upon a shared random value which none of them could have influenced or predicted in advance. This proposal outlines a simple one that isn't perfect (it's vulnerable to DOS and to limited influence by one or more collaborating hostile authorities), but it's quite simple, and it's meant to start discussion. I hope that we never build this, but instead replace it with something better. Some alternatives have already been discussed on tor-dev; more work is needed, though. (12/2013) 226 Scalability and Stability Improvements to BridgeDB: Switching to a Distributed Database System and RDBMS This one outlines design and behavior changes for a seriously refactored bridgedb. (2/2014) 227 Include package fingerprints in consensus documents Here we outline a scheme for including the digests of the latest versions of Tor software in consensuses, to help with update security. (2/2014) 228 Cross-certifying identity keys with onion keys This proposal signs each server's identity key with its onion keys, to prove onion key ownership in the router descriptor. It's not clear that this actually improves security, but it fixes an annoying gap in our key authentication. (2/2014) 229 Further SOCKS5 extensions Here's a nice idea for how we can support a new SOCKS5 protocol extension to relay information between clients and Tor, and between Tor and pluggable transports, more effectively. It also adds some additional SOCKS5 error codes. There are some open questions to answer. (2/2014) Since last time: 147 was closed as unnecessary. See discussion in the new "Reasons for Rejection" section at the end of that proprosal. 165 got clarified a little. 185 has been tweaked based on commentary from Karsten: the flag it proposes now works a little differently. 220 has been revised to have a more unified certificate format. 224 has been cleaned up, expanded, revised, and tightened. Proposals 226, 227, 228, and 229 are new.

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New conventions for Tor ticket milestones
by Nick Mathewson 28 Feb '14

28 Feb '14

(This is going to be interesting for people who use trac to look at tickets for the component "Tor" -- that is, the core Tor network daemon -- and basically nobody else.) Hi, all! 0.2.5 is getting close to feature-freeze time: by default, any feature for which the code is not already implemented is now targeted for 0.2.6 or later. We can make smart exceptions, but we need to be careful. Yes, I'm trying to get major releases out more frequently. My target is still 2-3 per year. But this isn't a freeze announcement: it's a trac milestone announcment. You see, around when we do a freeze for Tor 0.2.N, we usually take one or two passes through the tickets labelled "Tor: 0.2.N-final" and move most of them --the ones that we can defer-- into "Tor: 0.2.(N+1)-final". That's a silly way to handle milestones, and it's only going to get sillier as we do more frequent releases. It means that 0.2.5-final, for instance, contains "everything we want to do in 0.2.5.x-final" plus "everything we *would like to do* in 0.2.5.x-final, given infinite resources" So, as discussed at the dev meeting, now that I'm doing the first pass of ticket triage for 0.2.5.x-final, I'm splitting tickets into three places, not 1: * Tickets that we should really take another look at and try to resolve before 0.2.5.x is stable remain in "Tor: 0.2.5.x-final". * Tickets that I really believe we should do in the 0.2.6 go into "Tor: 0.2.6.x-final". As usual, no guarantees. * Tickets which I want to do "real soon now", maybe in the next release, but where they aren't blocking any particular release go into "Tor: 0.2.???". This is the new "We would like to do this any day now" milestone. Also, as before: * Tickets where I'm clueless go into "Tor: unspecified" I'm trying to mark tickets where we should consider a backport with the appropriate keywords. "025-backport" means "A fix for this is backportable into 0.2.5 if we solve it soon enough and the fix is clean enough", and so forth. These are, necessarily, fuzzy categories. I'm also going to make some triage mistakes over the next few days. If there's anything that I'm putting in the wrong milestone IYO, let's talk. best wishes, -- Nick Mathewson

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