tor-webwml.git

en/volunteer.wml    1) ## translation metadata

en/volunteer.wml    2) # Revision: $Revision$

en/volunteer.wml    3) # Translation-Priority: 4-optional

volunteer.html      4) 

en/volunteer.wml    5) #include "head.wmi" TITLE="Tor: Volunteer"

volunteer.html      6) 
volunteer.html      7) <div class="main-column">
volunteer.html      8) 
volunteer.html      9) <!-- PUT CONTENT AFTER THIS TAG -->

en/volunteer.wml   10) <h2>A few things everyone can do now:</h2>

volunteer.html     11) <ol>

en/volunteer.wml   12) <li>Please consider <a href="<page docs/tor-doc-relay>">running
en/volunteer.wml   13) a relay</a> to help the Tor network grow.</li>
en/volunteer.wml   14) <li>Tell your friends! Get them to run relays. Get them to run hidden

volunteer.html     15) services. Get them to tell their friends.</li>

en/volunteer.wml   16) <li>If you like Tor's goals, please <a href="<page donate>">take a moment
en/volunteer.wml   17) to donate to support further Tor development</a>. We're also looking
en/volunteer.wml   18) for more sponsors &mdash; if you know any companies, NGOs, agencies,
en/volunteer.wml   19) or other organizations that want anonymity / privacy / communications
en/volunteer.wml   20) security, let them know about us.</li>
en/volunteer.wml   21) <li>We're looking for more <a href="<page torusers>">good examples of Tor
en/volunteer.wml   22) users and Tor use cases</a>. If you use Tor for a scenario or purpose not
en/volunteer.wml   23) yet described on that page, and you're comfortable sharing it with us,
en/volunteer.wml   24) we'd love to hear from you.</li>

volunteer.html     25) </ol>
volunteer.html     26) 

en/volunteer.wml   27) <a id="Usability"></a>

en/volunteer.wml   28) <h2><a class="anchor" href="#Usability">Supporting Applications</a></h2>

volunteer.html     29) <ol>

en/volunteer.wml   30) <li>We need more and better ways to intercept DNS requests so they don't "leak" their

en/volunteer.wml   31) request to a local observer while we're trying to be anonymous. (This
en/volunteer.wml   32) happens because the application does the DNS resolve before going to
en/volunteer.wml   33) the SOCKS proxy.)</li>

en/volunteer.wml   34) <li>Tsocks/dsocks items:

en/volunteer.wml   35) <ul>
en/volunteer.wml   36) <li>We should patch Dug Song's "dsocks" program to use Tor's
en/volunteer.wml   37) <i>mapaddress</i> commands from the controller interface, so we
en/volunteer.wml   38) don't waste a whole round-trip inside Tor doing the resolve before
en/volunteer.wml   39) connecting.</li>
en/volunteer.wml   40) <li>We need to make our <i>torify</i> script detect which of tsocks or
en/volunteer.wml   41) dsocks is installed, and call them appropriately. This probably means
en/volunteer.wml   42) unifying their interfaces, and might involve sharing code between them
en/volunteer.wml   43) or discarding one entirely.</li>
en/volunteer.wml   44) </ul>

en/volunteer.wml   45) </li>

en/volunteer.wml   46) <li>People running relays tell us they want to have one BandwidthRate

en/volunteer.wml   47) during some part of the day, and a different BandwidthRate at other
en/volunteer.wml   48) parts of the day. Rather than coding this inside Tor, we should have a
en/volunteer.wml   49) little script that speaks via the <a href="<page gui/index>">Tor
en/volunteer.wml   50) Controller Interface</a>, and does a setconf to change the bandwidth

en/volunteer.wml   51) rate. There is one for Unix and Mac already (it uses bash and cron),

en/volunteer.wml   52) but Windows users still need a solution.

en/volunteer.wml   53) </li>

volunteer.html     54) <li>Speaking of geolocation data, somebody should draw a map of the Earth

en/volunteer.wml   55) with a pin-point for each Tor relay. Bonus points if it updates as the

en/volunteer.wml   56) network grows and changes. Unfortunately, the easy ways to do this involve
en/volunteer.wml   57) sending all the data to Google and having them draw the map for you. How
en/volunteer.wml   58) much does this impact privacy, and do we have any other good options?</li>

volunteer.html     59) </ol>
volunteer.html     60) 

en/volunteer.wml   61) <a id="Advocacy"></a>

en/volunteer.wml   62) <h2><a class="anchor" href="#Advocacy">Advocacy</a></h2>
en/volunteer.wml   63) <ol>
en/volunteer.wml   64) <li>Create a community logo under a Creative Commons license that all can use and modify</li>
en/volunteer.wml   65) <li>Create a presentation that can be used for various user group meetings around the world</li>
en/volunteer.wml   66) <li>Create a video about your positive uses of Tor.  Some have already started on Seesmic.</li>
en/volunteer.wml   67) <li>Create a poster, or a set of posters, around a theme, such as "Tor for Freedom!"</li>
en/volunteer.wml   68) </ol>
en/volunteer.wml   69) 

en/volunteer.wml   70) <a id="Documentation"></a>
en/volunteer.wml   71) <h2><a class="anchor" href="#Documentation">Documentation</a></h2>

volunteer.html     72) <ol>

en/volunteer.wml   73) <li>Please help Matt Edman with the documentation and how-tos for his

en/volunteer.wml   74) Tor controller,

en/volunteer.wml   75) <a href="<page vidalia/index>">Vidalia</a>.</li>

en/volunteer.wml   76) <li>Evaluate and document

en/volunteer.wml   77) <a href="https://wiki.torproject.org/wiki/TheOnionRouter/TorifyHOWTO">our

en/volunteer.wml   78) list of programs</a> that can be configured to use Tor.</li>

volunteer.html     79) <li>We need better documentation for dynamically intercepting

en/volunteer.wml   80) connections and sending them through Tor. tsocks (Linux), dsocks (BSD),

en/volunteer.wml   81) and freecap (Windows) seem to be good candidates, as would better
en/volunteer.wml   82) use of our new TransPort feature.</li>

en/volunteer.wml   83) <li>We have a huge list of <a href="https://wiki.torproject.org/noreply/TheOnionRouter/SupportPrograms">potentially useful

volunteer.html     84) programs that interface to Tor</a>. Which ones are useful in which
volunteer.html     85) situations? Please help us test them out and document your results.</li>

en/volunteer.wml   86) <li>Help translate the web page and documentation into other
en/volunteer.wml   87) languages. See the <a href="<page translation>">translation

en/volunteer.wml   88) guidelines</a> if you want to help out. We especially need Arabic or
en/volunteer.wml   89) Farsi translations, for the many Tor users in censored areas.</li>

volunteer.html     90) </ol>
volunteer.html     91) 

en/volunteer.wml   92) <a id="Coding"></a>

en/volunteer.wml   93) <a id="Summer"></a>
en/volunteer.wml   94) <a id="Projects"></a>

en/volunteer.wml   95) <h2><a class="anchor" href="#Projects">Good Coding Projects</a></h2>

en/volunteer.wml   96) 
en/volunteer.wml   97) <p>

en/volunteer.wml   98) You may find some of these projects to be good <a href="<page
en/volunteer.wml   99) gsoc>">Google Summer of Code 2009</a> ideas. We have labelled each idea
en/volunteer.wml  100) with how useful it would be to the overall Tor project (priority), how
en/volunteer.wml  101) much work we expect it would be (effort level), how much clue you should
en/volunteer.wml  102) start with (skill level), and which of our <a href="<page
en/volunteer.wml  103) people>#Core">core developers</a> would be good mentors.
en/volunteer.wml  104) If one or more of these ideas looks promising to you, please <a
en/volunteer.wml  105) href="<page contact>">contact us</a> to discuss your plans rather than
en/volunteer.wml  106) sending blind applications. You may also want to propose your own project
en/volunteer.wml  107) idea which often results in the best applications.

en/volunteer.wml  108) </p>
en/volunteer.wml  109) 

en/volunteer.wml  110) <ol>
en/volunteer.wml  111) 

en/volunteer.wml  112) <li>

en/volunteer.wml  113) <b>Tor Browser Bundle for Linux/Mac OS X</b>

en/volunteer.wml  114) <br />

en/volunteer.wml  115) Priority: <i>High</i>

en/volunteer.wml  116) <br />

en/volunteer.wml  117) Effort Level: <i>High</i>
en/volunteer.wml  118) <br />
en/volunteer.wml  119) Skill Level: <i>Medium</i>
en/volunteer.wml  120) <br />
en/volunteer.wml  121) Likely Mentors: <i>Steven, Andrew</i>
en/volunteer.wml  122) <br />
en/volunteer.wml  123) The Tor Browser bundle incorporates Tor, Firefox, and the Vidalia user
en/volunteer.wml  124) interface (and optionally Pidgin IM). Components are pre-configured to
en/volunteer.wml  125) operate in a secure way, and it has very few dependencies on the
en/volunteer.wml  126) installed operating system. It has therefore become one of the most
en/volunteer.wml  127) easy to use, and popular, ways to use Tor on Windows.
en/volunteer.wml  128) <br />
en/volunteer.wml  129) However, there is currently no comparable package for Linux and Mac OS
en/volunteer.wml  130) X, so this project would be to implement Tor Browser Bundle for these
en/volunteer.wml  131) platforms. This will involve modifications to Vidalia (C++), possibly
en/volunteer.wml  132) Firefox (C) then creating and testing the launcher on a range of
en/volunteer.wml  133) operating system versions and configurations to verify portability.
en/volunteer.wml  134) <br />
en/volunteer.wml  135) Students should be familiar with application development on one or
en/volunteer.wml  136) preferably both of Linux and Mac OS X, and be comfortable with C/C++
en/volunteer.wml  137) and shell scripting.
en/volunteer.wml  138) <br />
en/volunteer.wml  139) Part of this project could be usability testing of Tor Browser Bundle,
en/volunteer.wml  140) ideally amongst our target demographic.
en/volunteer.wml  141) That would help a lot in knowing what needs to be done in terms of bug
en/volunteer.wml  142) fixes or new features. We get this informally at the moment, but a more
en/volunteer.wml  143) structured process would be better.
en/volunteer.wml  144) </li>
en/volunteer.wml  145) 
en/volunteer.wml  146) <li>
en/volunteer.wml  147) <b>Translation wiki for our website</b>
en/volunteer.wml  148) <br />
en/volunteer.wml  149) Priority: <i>High</i>
en/volunteer.wml  150) <br />
en/volunteer.wml  151) Effort Level: <i>Medium</i>
en/volunteer.wml  152) <br />
en/volunteer.wml  153) Skill Level: <i>Medium</i>
en/volunteer.wml  154) <br />
en/volunteer.wml  155) Likely Mentors: <i>Jacob</i>
en/volunteer.wml  156) <br />
en/volunteer.wml  157) The Tor Project has been working over the past year to set up web-based
en/volunteer.wml  158) tools to help volunteers translate our applications into other languages.
en/volunteer.wml  159) We finally hit upon Pootle, and we have a fine web-based translation engine
en/volunteer.wml  160) in place for Vidalia, Torbutton, and Torcheck. However, Pootle only
en/volunteer.wml  161) translates strings that are in the "po" format, and our website uses wml
en/volunteer.wml  162) files. This project is about finding a way to convert our wml files into po
en/volunteer.wml  163) strings and back, so they can be handled by Pootle.

en/volunteer.wml  164) </li>
en/volunteer.wml  165) 
en/volunteer.wml  166) <li>
en/volunteer.wml  167) <b>Help track the overall Tor Network status</b>

en/volunteer.wml  168) <br />

en/volunteer.wml  169) Priority: <i>Medium to High</i>
en/volunteer.wml  170) <br />
en/volunteer.wml  171) Effort Level: <i>Medium</i>
en/volunteer.wml  172) <br />
en/volunteer.wml  173) Skill Level: <i>Medium</i>
en/volunteer.wml  174) <br />

en/volunteer.wml  175) Likely Mentors: <i>Karsten, Roger</i>

en/volunteer.wml  176) <br />

en/volunteer.wml  177) It would be great to set up an automated system for tracking network
en/volunteer.wml  178) health over time, graphing it, etc. Part of this project would involve
en/volunteer.wml  179) inventing better metrics for assessing network health and growth. Is the
en/volunteer.wml  180) average uptime of the network increasing? How many relays are qualifying
en/volunteer.wml  181) for Guard status this month compared to last month? What's the turnover
en/volunteer.wml  182) in terms of new relays showing up and relays shutting off? Periodically
en/volunteer.wml  183) people collect brief snapshots, but where it gets really interesting is
en/volunteer.wml  184) when we start tracking data points over time.
en/volunteer.wml  185) <br />

en/volunteer.wml  186) Data could be collected from the Tor Network Scanners in <a
en/volunteer.wml  187) href="https://svn.torproject.org/svn/torflow/trunk/README">TorFlow</a>, from

en/volunteer.wml  188) the server descriptors that each relay publishes, and from other
en/volunteer.wml  189) sources. Results over time could be integrated into one of the <a
en/volunteer.wml  190) href="https://torstatus.blutmagie.de/">Tor Status</a> web pages, or be
en/volunteer.wml  191) kept separate. Speaking of the Tor Status pages, take a look at Roger's
en/volunteer.wml  192) <a href="http://archives.seul.org/or/talk/Jan-2008/msg00300.html">Tor
en/volunteer.wml  193) Status wish list</a>.
en/volunteer.wml  194) </li>
en/volunteer.wml  195) 
en/volunteer.wml  196) <li>
en/volunteer.wml  197) <b>Improving Tor's ability to resist censorship</b>
en/volunteer.wml  198) <br />

en/volunteer.wml  199) Priority: <i>Medium to High</i>

en/volunteer.wml  200) <br />

en/volunteer.wml  201) Effort Level: <i>Medium</i>

en/volunteer.wml  202) <br />
en/volunteer.wml  203) Skill Level: <i>High</i>
en/volunteer.wml  204) <br />

en/volunteer.wml  205) Likely Mentors: <i>Nick, Roger, Steven</i>

en/volunteer.wml  206) <br />

en/volunteer.wml  207) The Tor 0.2.0.x series makes <a
en/volunteer.wml  208) href="<svnsandbox>doc/design-paper/blocking.html">significant
en/volunteer.wml  209) improvements</a> in resisting national and organizational censorship.
en/volunteer.wml  210) But Tor still needs better mechanisms for some parts of its
en/volunteer.wml  211) anti-censorship design.  For example, current Tors can only listen on a
en/volunteer.wml  212) single address/port combination at a time.  There's
en/volunteer.wml  213) <a href="<svnsandbox>doc/spec/proposals/118-multiple-orports.txt">a
en/volunteer.wml  214) proposal to address this limitation</a> and allow clients to connect
en/volunteer.wml  215) to any given Tor on multiple addresses and ports, but it needs more
en/volunteer.wml  216) work.  Another anti-censorship project (far more difficult) is to try
en/volunteer.wml  217) to make Tor more scanning-resistant.  Right now, an adversary can identify
en/volunteer.wml  218) <a href="<svnsandbox>doc/spec/proposals/125-bridges.txt">Tor bridges</a>
en/volunteer.wml  219) just by trying to connect to them, following the Tor protocol, and
en/volunteer.wml  220) seeing if they respond.  To solve this, bridges could
en/volunteer.wml  221) <a href="<svnsandbox>doc/design-paper/blocking.html#tth_sEc9.3">act like
en/volunteer.wml  222) webservers</a> (HTTP or HTTPS) when contacted by port-scanning tools,
en/volunteer.wml  223) and not act like bridges until the user provides a bridge-specific key.
en/volunteer.wml  224) <br />
en/volunteer.wml  225) This project involves a lot of research and design. One of the big
en/volunteer.wml  226) challenges will be identifying and crafting approaches that can still
en/volunteer.wml  227) resist an adversary even after the adversary knows the design, and
en/volunteer.wml  228) then trading off censorship resistance with usability and robustness.
en/volunteer.wml  229) </li>
en/volunteer.wml  230) 
en/volunteer.wml  231) <li>

en/volunteer.wml  232) <b>Tuneup Tor!</b>

en/volunteer.wml  233) <br />

en/volunteer.wml  234) Priority: <i>Medium to High</i>

en/volunteer.wml  235) <br />

en/volunteer.wml  236) Effort Level: <i>Medium to High</i>

en/volunteer.wml  237) <br />

en/volunteer.wml  238) Skill Level: <i>High</i>
en/volunteer.wml  239) <br />
en/volunteer.wml  240) Likely Mentors: <i>Nick, Roger, Mike, Karsten</i>
en/volunteer.wml  241) <br />
en/volunteer.wml  242) Right now, Tor relays measure and report their own bandwidth, and Tor
en/volunteer.wml  243) clients choose which relays to use in part based on that bandwidth.
en/volunteer.wml  244) This approach is vulnerable to
en/volunteer.wml  245) <a href="http://freehaven.net/anonbib/#bauer:wpes2007">attacks where
en/volunteer.wml  246) relays lie about their bandwidth</a>;
en/volunteer.wml  247) to address this, Tor currently caps the maximum bandwidth
en/volunteer.wml  248) it's willing to believe any relay provides.  This is a limited fix, and
en/volunteer.wml  249) a waste of bandwidth capacity to boot.  Instead,
en/volunteer.wml  250) Tor should possibly measure bandwidth in a more distributed way, perhaps
en/volunteer.wml  251) as described in the
en/volunteer.wml  252) <a href="http://freehaven.net/anonbib/author.html#snader08">"A Tune-up for
en/volunteer.wml  253) Tor"</a> paper
en/volunteer.wml  254) by Snader and Borisov. One could use current testing code to
en/volunteer.wml  255) double-check this paper's findings and verify the extent to which they
en/volunteer.wml  256) dovetail with Tor as deployed in the wild, and determine good ways to
en/volunteer.wml  257) incorporate them into their suggestions Tor network without adding too
en/volunteer.wml  258) much communications overhead between relays and directory
en/volunteer.wml  259) authorities.

en/volunteer.wml  260) </li>
en/volunteer.wml  261) 
en/volunteer.wml  262) <li>

en/volunteer.wml  263) <b>Improving Polipo on Windows</b>

en/volunteer.wml  264) <br />

en/volunteer.wml  265) Priority: <i>Medium to High</i>

en/volunteer.wml  266) <br />
en/volunteer.wml  267) Effort Level: <i>Medium</i>
en/volunteer.wml  268) <br />
en/volunteer.wml  269) Skill Level: <i>Medium</i>
en/volunteer.wml  270) <br />

en/volunteer.wml  271) Likely Mentors: <i>Martin</i>

en/volunteer.wml  272) <br />

en/volunteer.wml  273) Help port <a
en/volunteer.wml  274) href="http://www.pps.jussieu.fr/~jch/software/polipo/">Polipo</a> to
en/volunteer.wml  275) Windows. Example topics to tackle include:
en/volunteer.wml  276) 1) the ability to asynchronously
en/volunteer.wml  277) query name servers, find the system nameservers, and manage netbios
en/volunteer.wml  278) and dns queries.
en/volunteer.wml  279) 2) manage events and buffers
en/volunteer.wml  280) natively (i.e. in Unix-like OSes, Polipo defaults to 25% of ram, in
en/volunteer.wml  281) Windows it's whatever the config specifies). 3) some sort of GUI config
en/volunteer.wml  282) and reporting tool, bonus if it has a systray icon with right clickable
en/volunteer.wml  283) menu options. Double bonus if it's cross-platform compatible.

en/volunteer.wml  284) 4) allow the software to use the Windows Registry and handle proper
en/volunteer.wml  285) Windows directory locations, such as "C:\Program Files\Polipo"

en/volunteer.wml  286) </li>
en/volunteer.wml  287) 
en/volunteer.wml  288) <li>
en/volunteer.wml  289) <b>Implement a torrent-based scheme for downloading Thandy packages</b>

en/volunteer.wml  290) <br />

en/volunteer.wml  291) Priority: <i>Medium to High</i>

en/volunteer.wml  292) <br />

en/volunteer.wml  293) Effort Level: <i>High</i>
en/volunteer.wml  294) <br />
en/volunteer.wml  295) Skill Level: <i>Medium to High</i>
en/volunteer.wml  296) <br />
en/volunteer.wml  297) Likely Mentors: <i>Martin, Nick</i>
en/volunteer.wml  298) <br />
en/volunteer.wml  299) <a

en/volunteer.wml  300) href="https://git.torproject.org/checkout/thandy/master/specs/thandy-spec.txt">Thandy</a>

en/volunteer.wml  301) is a relatively new software to allow assisted updates of Tor and related
en/volunteer.wml  302) software. Currently, there are very few users, but we expect Thandy to be
en/volunteer.wml  303) used by almost every Tor user in the future. To avoid crashing servers on
en/volunteer.wml  304) the day of a Tor update, we need new ways to distribute new packages
en/volunteer.wml  305) efficiently, and using libtorrent seems to be a possible solution. If you
en/volunteer.wml  306) think of other good ideas, great - please do let us know!<br />
en/volunteer.wml  307) We also need to investigate how to include our mirrors better. If possible,
en/volunteer.wml  308) there should be an easy way for them to help distributing the packages.

en/volunteer.wml  309) </li>
en/volunteer.wml  310) 

en/volunteer.wml  311) <li>

en/volunteer.wml  312) <b>Tor Controller Status Event Interface</b>

en/volunteer.wml  313) <br />

en/volunteer.wml  314) Priority: <i>Medium</i>
en/volunteer.wml  315) <br />
en/volunteer.wml  316) Effort Level: <i>Medium</i>
en/volunteer.wml  317) <br />

en/volunteer.wml  318) Skill Level: <i>Low to Medium</i>

en/volunteer.wml  319) <br />
en/volunteer.wml  320) Likely Mentors: <i>Matt</i>
en/volunteer.wml  321) <br />

en/volunteer.wml  322) There are a number of status changes inside Tor of which the user may need

en/volunteer.wml  323) to be informed. For example, if the user is trying to set up his Tor as a
en/volunteer.wml  324) relay and Tor decides that its ports are not reachable from outside

en/volunteer.wml  325) the user's network, we should alert the user. Currently, all the user

en/volunteer.wml  326) gets is a couple log messages in Vidalia's 'message log' window, which they

en/volunteer.wml  327) likely never see since they don't receive a notification that something
en/volunteer.wml  328) has gone wrong. Even if the user does actually look at the message log,
en/volunteer.wml  329) most of the messages make little sense to the novice user.
en/volunteer.wml  330) <br />
en/volunteer.wml  331) Tor has the ability to inform Vidalia of many such status changes, and
en/volunteer.wml  332) we recently implemented support for a couple of these events. Still,
en/volunteer.wml  333) there are many more status events the user should be informed of and we
en/volunteer.wml  334) need a better UI for actually displaying them to the user.
en/volunteer.wml  335) <br />
en/volunteer.wml  336) The goal of this project then is to design and implement a UI for
en/volunteer.wml  337) displaying Tor status events to the user. For example, we might put a
en/volunteer.wml  338) little badge on Vidalia's tray icon that alerts the user to new status
en/volunteer.wml  339) events they should look at. Double-clicking the icon could bring up a
en/volunteer.wml  340) dialog that summarizes recent status events in simple terms and maybe

en/volunteer.wml  341) suggests a remedy for any negative events if they can be corrected by

en/volunteer.wml  342) the user. Of course, this is just an example and one is free to

en/volunteer.wml  343) suggest another approach.
en/volunteer.wml  344) <br />

en/volunteer.wml  345) A person undertaking this project should have good UI design and layout

en/volunteer.wml  346) and some C++ development experience. Previous experience with Qt and

en/volunteer.wml  347) Qt's Designer will be very helpful, but are not required. Some

en/volunteer.wml  348) English writing ability will also be useful, since this project will
en/volunteer.wml  349) likely involve writing small amounts of help documentation that should
en/volunteer.wml  350) be understandable by non-technical users. Bonus points for some graphic
en/volunteer.wml  351) design/Photoshop fu, since we might want/need some shiny new icons too.
en/volunteer.wml  352) </li>
en/volunteer.wml  353) 

en/volunteer.wml  354) <li>

en/volunteer.wml  355) <b>Improve our unit testing process</b>

en/volunteer.wml  356) <br />

en/volunteer.wml  357) Priority: <i>Medium</i>

en/volunteer.wml  358) <br />

en/volunteer.wml  359) Effort Level: <i>Medium</i>
en/volunteer.wml  360) <br />
en/volunteer.wml  361) Skill Level: <i>Medium</i>
en/volunteer.wml  362) <br />
en/volunteer.wml  363) Likely Mentors: <i>Nick, Roger</i>
en/volunteer.wml  364) <br />
en/volunteer.wml  365) Tor needs to be far more tested. This is a multi-part effort. To start
en/volunteer.wml  366) with, our unit test coverage should rise substantially, especially in
en/volunteer.wml  367) the areas outside the utility functions. This will require significant
en/volunteer.wml  368) refactoring of some parts of Tor, in order to dissociate as much logic
en/volunteer.wml  369) as possible from globals.
en/volunteer.wml  370) <br />
en/volunteer.wml  371) Additionally, we need to automate our performance testing. We've got
en/volunteer.wml  372) buildbot to automate our regular integration and compile testing already
en/volunteer.wml  373) (though we need somebody to set it up on Windows),
en/volunteer.wml  374) but we need to get our network simulation tests (as built in <a
en/volunteer.wml  375) href="https://svn.torproject.org/svn/torflow/trunk/README">TorFlow</a>)
en/volunteer.wml  376) updated for more recent versions of Tor, and designed to launch a test
en/volunteer.wml  377) network either on a single machine, or across several, so we can test
en/volunteer.wml  378) changes in performance on machines in different roles automatically.
en/volunteer.wml  379) </li>
en/volunteer.wml  380) 
en/volunteer.wml  381) <li>
en/volunteer.wml  382) <b>Help revive an independent Tor client implementation</b>
en/volunteer.wml  383) <br />
en/volunteer.wml  384) Priority: <i>Medium</i>
en/volunteer.wml  385) <br />
en/volunteer.wml  386) Effort Level: <i>High</i>
en/volunteer.wml  387) <br />
en/volunteer.wml  388) Skill Level: <i>Medium to High</i>
en/volunteer.wml  389) <br />
en/volunteer.wml  390) Likely Mentors: <i>Karsten, Nick</i>
en/volunteer.wml  391) <br />
en/volunteer.wml  392) Reanimate one of the approaches to implement a Tor client in Java,
en/volunteer.wml  393) e.g. the <a href="http://onioncoffee.sourceforge.net/">OnionCoffee
en/volunteer.wml  394) project</a>, and make it run on <a
en/volunteer.wml  395) href="http://code.google.com/android/">Android</a>. The first step
en/volunteer.wml  396) would be to port the existing code and execute it in an Android
en/volunteer.wml  397) environment. Next, the code should be updated to support the newer Tor
en/volunteer.wml  398) protocol versions like the <a href="<svnsandbox>doc/spec/dir-spec.txt">v3
en/volunteer.wml  399) directory protocol</a>. Further, support for requesting or even
en/volunteer.wml  400) providing Tor hidden services would be neat, but not required.
en/volunteer.wml  401) <br />
en/volunteer.wml  402) A prospective developer should be able to understand and write new Java
en/volunteer.wml  403) code, including
en/volunteer.wml  404) a Java cryptography API. Being able to read C code would be helpful,
en/volunteer.wml  405) too. One should be willing to read the existing documentation,
en/volunteer.wml  406) implement code based on it, and refine the documentation
en/volunteer.wml  407) when things are underdocumented. This project is mostly about coding and
en/volunteer.wml  408) to a small degree about design.
en/volunteer.wml  409) </li>
en/volunteer.wml  410) 
en/volunteer.wml  411) <li>
en/volunteer.wml  412) <b>New Torbutton Features</b>
en/volunteer.wml  413) <br />
en/volunteer.wml  414) Priority: <i>Medium</i>
en/volunteer.wml  415) <br />
en/volunteer.wml  416) Effort Level: <i>High</i>
en/volunteer.wml  417) <br />
en/volunteer.wml  418) Skill Level: <i>High</i>
en/volunteer.wml  419) <br />
en/volunteer.wml  420) Likely Mentors: <i>Mike</i>
en/volunteer.wml  421) <br/>
en/volunteer.wml  422) There are several <a
en/volunteer.wml  423) href="https://bugs.torproject.org/flyspray/index.php?tasks=all&amp;project=5&amp;type=2">good
en/volunteer.wml  424) feature requests</a> on the Torbutton Flyspray section. In particular, <a
en/volunteer.wml  425) href="https://bugs.torproject.org/flyspray/index.php?do=details&amp;id=523">Integrating
en/volunteer.wml  426) 'New Identity' with Vidalia</a>,
en/volunteer.wml  427) <a href="https://bugs.torproject.org/flyspray/index.php?do=details&amp;id=940">ways of
en/volunteer.wml  428) managing multiple cookie jars/identities</a>, <a
en/volunteer.wml  429) href="https://bugs.torproject.org/flyspray/index.php?do=details&amp;id=637">preserving
en/volunteer.wml  430) specific cookies</a> when cookies are cleared,
en/volunteer.wml  431) <a
en/volunteer.wml  432) href="https://bugs.torproject.org/flyspray/index.php?do=details&amp;id=524">better
en/volunteer.wml  433) referrer spoofing</a>, <a
en/volunteer.wml  434) href="https://bugs.torproject.org/flyspray/index.php?do=details&amp;id=564">correct
en/volunteer.wml  435) Tor status reporting</a>, and <a
en/volunteer.wml  436) href="https://bugs.torproject.org/flyspray/index.php?do=details&amp;id=462">"tor://"
en/volunteer.wml  437) and "tors://" urls</a> are all interesting
en/volunteer.wml  438) features that could be added.
en/volunteer.wml  439) <br />
en/volunteer.wml  440) This work would be independent coding in Javascript and the fun world of <a
en/volunteer.wml  441) href="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">XUL</a>,
en/volunteer.wml  442) with not too much involvement in the Tor internals.
en/volunteer.wml  443) </li>
en/volunteer.wml  444) 
en/volunteer.wml  445) <li>
en/volunteer.wml  446) <b>New Thandy Features</b>
en/volunteer.wml  447) <br />
en/volunteer.wml  448) Priority: <i>Medium</i>
en/volunteer.wml  449) <br />
en/volunteer.wml  450) Effort Level: <i>Medium</i>
en/volunteer.wml  451) <br />
en/volunteer.wml  452) Skill Level: <i>Medium to High</i>
en/volunteer.wml  453) <br />
en/volunteer.wml  454) Likely Mentors: <i>Martin</i>
en/volunteer.wml  455) <br />
en/volunteer.wml  456) Additional capabilities are needed for assisted updates of all the Tor
en/volunteer.wml  457) related software for Windows and other operating systems. Some of the
en/volunteer.wml  458) features to consider include:
en/volunteer.wml  459) 1) Integration of the <a
en/volunteer.wml  460) href="http://chandlerproject.org/Projects/MeTooCrypto">MeTooCrypto
en/volunteer.wml  461) Python library</a>
en/volunteer.wml  462) for authenticated HTTPS downloads. 2) Adding a level of indirection
en/volunteer.wml  463) between the timestamp signatures and the package files included in an
en/volunteer.wml  464) update. See the "Thandy attacks / suggestions" thread on or-dev.
en/volunteer.wml  465) 3) Support locale specific installation and configuration of assisted
en/volunteer.wml  466) updates based on preference, host, or user account language settings.
en/volunteer.wml  467) Familiarity with Windows codepages, unicode, and other character sets
en/volunteer.wml  468) is helpful in addition to general win32 and posix API experience and
en/volunteer.wml  469) Python proficiency.
en/volunteer.wml  470) </li>
en/volunteer.wml  471) 
en/volunteer.wml  472) <li>
en/volunteer.wml  473) <b>Simulator for slow Internet connections</b>
en/volunteer.wml  474) <br />
en/volunteer.wml  475) Priority: <i>Medium</i>
en/volunteer.wml  476) <br />
en/volunteer.wml  477) Effort Level: <i>Medium</i>
en/volunteer.wml  478) <br />
en/volunteer.wml  479) Skill Level: <i>Medium</i>
en/volunteer.wml  480) <br />
en/volunteer.wml  481) Likely Mentors: <i>Steven</i>
en/volunteer.wml  482) <br />
en/volunteer.wml  483) Many users of Tor have poor-quality Internet connections, giving low
en/volunteer.wml  484) bandwidth, high latency, and high packet loss/re-ordering. User
en/volunteer.wml  485) experience is that Tor reacts badly to these conditions, but it is
en/volunteer.wml  486) difficult to improve the situation without being able to repeat the
en/volunteer.wml  487) problems in the lab.
en/volunteer.wml  488) <br />
en/volunteer.wml  489) This project would be to build a simulation environment which
en/volunteer.wml  490) replicates the poor connectivity so that the effect on Tor performance
en/volunteer.wml  491) can be measured. Other components would be a testing utility to
en/volunteer.wml  492) establish what are the properties of connections available, and to
en/volunteer.wml  493) measure the effect of performance-improving modifications to Tor.
en/volunteer.wml  494) <br />
en/volunteer.wml  495) The tools used would be up to the student, but dummynet (for FreeBSD)
en/volunteer.wml  496) and nistnet (for Linux) are two potential components on which this
en/volunteer.wml  497) project could be built. Students should be experienced with network
en/volunteer.wml  498) programming/debugging and TCP/IP, and preferably familiar with C and a
en/volunteer.wml  499) scripting language.
en/volunteer.wml  500) </li>
en/volunteer.wml  501) 
en/volunteer.wml  502) <li>
en/volunteer.wml  503) <b>An Improved and More Usable Network Map in Vidalia</b>
en/volunteer.wml  504) <br />
en/volunteer.wml  505) Priority: <i>Low to Medium</i>
en/volunteer.wml  506) <br />
en/volunteer.wml  507) Effort Level: <i>Medium</i>
en/volunteer.wml  508) <br />
en/volunteer.wml  509) Skill Level: <i>Medium</i>
en/volunteer.wml  510) <br />
en/volunteer.wml  511) Likely Mentors: <i>Matt</i>
en/volunteer.wml  512) <br />
en/volunteer.wml  513) One of Vidalia's existing features is a network map that shows the user
en/volunteer.wml  514) the approximate geographic location of relays in the Tor network and
en/volunteer.wml  515) plots the paths the user's traffic takes as it is tunneled through the
en/volunteer.wml  516) Tor network. The map is currently not very interactive and has rather
en/volunteer.wml  517) poor graphics. Instead, we implemented KDE's Marble widget such
en/volunteer.wml  518) that it gives us a better quality map and enables improved interactivity,
en/volunteer.wml  519) such as allowing the user to click on individual relays or circuits to
en/volunteer.wml  520) display additional information. We want to add the ability
en/volunteer.wml  521) for users to click on a particular relay or a country containing one or
en/volunteer.wml  522) more Tor exit relays and say, "I want my connections to exit
en/volunteer.wml  523) from here."
en/volunteer.wml  524) <br />
en/volunteer.wml  525) This project will first involve getting familiar with Vidalia
en/volunteer.wml  526) and the Marble widget's API. One will then integrate the widget
en/volunteer.wml  527) into Vidalia and customize Marble to be better suited for our application,
en/volunteer.wml  528) such as making circuits clickable, storing cached map data in Vidalia's
en/volunteer.wml  529) own data directory, and customizing some of the widget's dialogs.
en/volunteer.wml  530) <br />
en/volunteer.wml  531) A person undertaking this project should have good C++ development
en/volunteer.wml  532) experience. Previous experience with Qt and CMake is helpful, but not
en/volunteer.wml  533) required.
en/volunteer.wml  534) </li>
en/volunteer.wml  535) 
en/volunteer.wml  536) <li>
en/volunteer.wml  537) <b>Bring moniTor to life</b>
en/volunteer.wml  538) <br />
en/volunteer.wml  539) Priority: <i>Low</i>
en/volunteer.wml  540) <br />
en/volunteer.wml  541) Effort Level: <i>Medium</i>
en/volunteer.wml  542) <br />
en/volunteer.wml  543) Skill Level: <i>Low to Medium</i>
en/volunteer.wml  544) <br />
en/volunteer.wml  545) Likely Mentors: <i>Karsten, Jacob</i>
en/volunteer.wml  546) <br />
en/volunteer.wml  547) Implement a <a href="http://www.ss64.com/bash/top.html">top-like</a>
en/volunteer.wml  548) management tool for Tor relays. The purpose of such a tool would be
en/volunteer.wml  549) to monitor a local Tor relay via its control port and include useful
en/volunteer.wml  550) system information of the underlying machine. When running this tool, it
en/volunteer.wml  551) would dynamically update its content like top does for Linux processes.
en/volunteer.wml  552) <a href="http://archives.seul.org/or/dev/Jan-2008/msg00005.html">This
en/volunteer.wml  553) or-dev post</a> might be a good first read.
en/volunteer.wml  554) <br />
en/volunteer.wml  555) A person interested in this should be familiar
en/volunteer.wml  556) with or willing to learn about administering a Tor relay and configuring
en/volunteer.wml  557) it via its control port. As an initial prototype is written in Python,
en/volunteer.wml  558) some knowledge about writing Python code would be helpful, too. This
en/volunteer.wml  559) project is one part about identifying requirements to such a
en/volunteer.wml  560) tool and designing its interface, and one part lots of coding.
en/volunteer.wml  561) </li>
en/volunteer.wml  562) 
en/volunteer.wml  563) <li>
en/volunteer.wml  564) <b>Torbutton equivalent for Thunderbird</b>
en/volunteer.wml  565) <br />
en/volunteer.wml  566) Priority: <i>Low</i>
en/volunteer.wml  567) <br />
en/volunteer.wml  568) Effort Level: <i>High</i>
en/volunteer.wml  569) <br />
en/volunteer.wml  570) Skill Level: <i>High</i>
en/volunteer.wml  571) <br />
en/volunteer.wml  572) Likely Mentors: <i>Mike</i>
en/volunteer.wml  573) <br />
en/volunteer.wml  574) We're hearing from an increasing number of users that they want to use
en/volunteer.wml  575) Thunderbird with Tor. However, there are plenty of application-level
en/volunteer.wml  576) concerns, for example, by default Thunderbird will put your hostname in
en/volunteer.wml  577) the outgoing mail that it sends. At some point we should start a new
en/volunteer.wml  578) push to build a Thunderbird extension similar to Torbutton.
en/volunteer.wml  579) </li>
en/volunteer.wml  580) 
en/volunteer.wml  581) <li>
en/volunteer.wml  582) <b>Intermediate Level Network Device Driver</b>
en/volunteer.wml  583) <br />
en/volunteer.wml  584) Priority: <i>Low</i>
en/volunteer.wml  585) <br />
en/volunteer.wml  586) Effort Level: <i>High</i>
en/volunteer.wml  587) <br />
en/volunteer.wml  588) Skill Level: <i>High</i>
en/volunteer.wml  589) <br />
en/volunteer.wml  590) Likely Mentors: <i>Martin</i>
en/volunteer.wml  591) <br />
en/volunteer.wml  592) The WinPCAP device driver used by Tor VM for bridged networking does
en/volunteer.wml  593) not support a number of wireless and non-Ethernet network adapters.
en/volunteer.wml  594) Implementation of a intermediate level network device driver for win32
en/volunteer.wml  595) and 64bit would provide a way to intercept and route traffic over such
en/volunteer.wml  596) networks. This project will require knowledge of and experience with
en/volunteer.wml  597) Windows kernel device driver development and testing. Familiarity with
en/volunteer.wml  598) Winsock and Qemu would also be helpful.
en/volunteer.wml  599) </li>
en/volunteer.wml  600) 

en/volunteer.wml  601) <li>
en/volunteer.wml  602) <b>Improve Tor Weather</b>
en/volunteer.wml  603) <br />
en/volunteer.wml  604) Priority: <i>Medium</i>
en/volunteer.wml  605) <br />
en/volunteer.wml  606) Effort Level: <i>Medium</i>
en/volunteer.wml  607) <br />
en/volunteer.wml  608) Skill Level: <i>Medium</i>
en/volunteer.wml  609) <br />

en/volunteer.wml  610) Likely Mentors: <i>Jake, Roger</i>

en/volunteer.wml  611) <br />
en/volunteer.wml  612) <a href="https://weather.torproject.org/">Tor weather</a> is a tool
en/volunteer.wml  613) that allows signing up to receive notifications via email when the
en/volunteer.wml  614) tracked Tor relay is down. Currently, it isn't really useful for
en/volunteer.wml  615) people who use the hibernation feature of Tor, or for those who
en/volunteer.wml  616) have to shut down their relay regularly. During the project, Tor

en/volunteer.wml  617) weather could be extended to allow more flexible configurations.

en/volunteer.wml  618) Other enhancements are also possible: Weather could send out warnings

en/volunteer.wml  619) when your relay runs an out-of-date version of Tor, or when its

en/volunteer.wml  620) observed bandwith drops below a certain value. It might also be a
en/volunteer.wml  621) nice tool that allows for checking whether your relay has earned

en/volunteer.wml  622) you a <a href="<page tshirt>">T-Shirt</a>, or sending reminders to
en/volunteer.wml  623) directory authorities that
en/volunteer.wml  624) their keys are about to expire. Be creative, and consider how the
en/volunteer.wml  625) above project to track overall network status can help you get your job
en/volunteer.wml  626) done more quickly! See also its
en/volunteer.wml  627) <a href="https://svn.torproject.org/svn/weather/trunk/README">README</a>
en/volunteer.wml  628) and <a href="https://svn.torproject.org/svn/weather/trunk/TODO">TODO</a>.

en/volunteer.wml  629) </li>
en/volunteer.wml  630) 

en/volunteer.wml  631) <li>
en/volunteer.wml  632) <b>Bring up new ideas!</b>
en/volunteer.wml  633) <br />
en/volunteer.wml  634) Don't like any of these? Look at the <a
en/volunteer.wml  635) href="<svnsandbox>doc/roadmaps/2008-12-19-roadmap-full.pdf">Tor development
en/volunteer.wml  636) roadmap</a> for more ideas.
en/volunteer.wml  637) Some of the <a href="<svnsandbox>doc/spec/proposals/">current proposals</a>
en/volunteer.wml  638) might also be short on developers.
en/volunteer.wml  639) </li>
en/volunteer.wml  640) 
en/volunteer.wml  641) <!-- Mike is already working on this.
en/volunteer.wml  642) <li>
en/volunteer.wml  643) <b>Tor Node Scanner improvements</b>
en/volunteer.wml  644) <br />
en/volunteer.wml  645) Similar to the SoaT exit scanner (or perhaps even during exit scanning),
en/volunteer.wml  646) statistics can be gathered about the reliability of nodes. Nodes that
en/volunteer.wml  647) fail too high a percentage of their circuits should not be given
en/volunteer.wml  648) Guard status. Perhaps they should have their reported bandwidth
en/volunteer.wml  649) penalized by some ratio as well, or just get marked as Invalid. In
en/volunteer.wml  650) addition, nodes that exhibit a very low average stream capacity but
en/volunteer.wml  651) advertise a very high node bandwidth can also be marked as Invalid.
en/volunteer.wml  652) Much of this statistics gathering is already done, it just needs to be
en/volunteer.wml  653) transformed into something that can be reported to the Directory
en/volunteer.wml  654) Authorities to blacklist/penalize nodes in such a way that clients
en/volunteer.wml  655) will listen.
en/volunteer.wml  656) <br />
en/volunteer.wml  657) In addition, these same statistics can be gathered about the traffic
en/volunteer.wml  658) through a node. Events can be added to the <a
en/volunteer.wml  659) href="https://svn.torproject.org/svn/torctl/trunk/doc/howto.txt">Tor Control
en/volunteer.wml  660) Protocol</a> to
en/volunteer.wml  661) report if a circuit extend attempt through the node succeeds or fails, and
en/volunteer.wml  662) passive statistics can be gathered on both bandwidth and reliability
en/volunteer.wml  663) of other nodes via a node-based monitor using these events. Such a
en/volunteer.wml  664) scanner would also report information on oddly-behaving nodes to
en/volunteer.wml  665) the Directory Authorities, but a communication channel for this
en/volunteer.wml  666) currently does not exist and would need to be developed as well.
en/volunteer.wml  667) </li>
en/volunteer.wml  668) -->
en/volunteer.wml  669) 
en/volunteer.wml  670) <!-- Is this still a useful project? If so, move it to another section.
en/volunteer.wml  671) <li>
en/volunteer.wml  672) <b>Better Debian/Ubuntu Packaging for Tor+Vidalia</b>
en/volunteer.wml  673) <br />
en/volunteer.wml  674) Vidalia currently doesn't play nicely on Debian and Ubuntu with the
en/volunteer.wml  675) default Tor packages. The current Tor packages automatically start Tor
en/volunteer.wml  676) as a daemon running as the debian-tor user and (sensibly) do not have a
en/volunteer.wml  677) <a href="<svnsandbox>doc/spec/control-spec.txt">ControlPort</a> defined
en/volunteer.wml  678) in the default torrc. Consequently, Vidalia will try
en/volunteer.wml  679) to start its own Tor process since it could not connect to the existing
en/volunteer.wml  680) Tor, and Vidalia's Tor process will then exit with an error message
en/volunteer.wml  681) the user likely doesn't understand since Tor cannot bind its listening
en/volunteer.wml  682) ports &mdash; they're already in use by the original Tor daemon.
en/volunteer.wml  683) <br />
en/volunteer.wml  684) The current solution involves either telling the user to stop the
en/volunteer.wml  685) existing Tor daemon and let Vidalia start its own Tor process, or
en/volunteer.wml  686) explaining to the user how to set a control port and password in their
en/volunteer.wml  687) torrc. A better solution on Debian would be to use Tor's ControlSocket,
en/volunteer.wml  688) which allows Vidalia to talk to Tor via a Unix domain socket, and could
en/volunteer.wml  689) possibly be enabled by default in Tor's Debian packages. Vidalia can
en/volunteer.wml  690) then authenticate to Tor using filesystem-based (cookie) authentication
en/volunteer.wml  691) if the user running Vidalia is also in the debian-tor group.
en/volunteer.wml  692) <br />
en/volunteer.wml  693) This project will first involve adding support for Tor's ControlSocket
en/volunteer.wml  694) to Vidalia. The student will then develop and test Debian and Ubuntu
en/volunteer.wml  695) packages for Vidalia that conform to Debian's packaging standards and
en/volunteer.wml  696) make sure they work well with the existing Tor packages. We can also
en/volunteer.wml  697) set up an apt repository to host the new Vidalia packages.
en/volunteer.wml  698) <br />
en/volunteer.wml  699) The next challenge would be to find an intuitive usable way for Vidalia
en/volunteer.wml  700) to be able to change Tor's configuration (torrc) even though it is
en/volunteer.wml  701) located in <code>/etc/tor/torrc</code> and thus immutable. The best
en/volunteer.wml  702) idea we've come up with so far is to feed Tor a new configuration via
en/volunteer.wml  703) the ControlSocket when Vidalia starts, but that's bad because Tor starts
en/volunteer.wml  704) each boot with a different configuration than the user wants. The second
en/volunteer.wml  705) best idea
en/volunteer.wml  706) we've come up with is for Vidalia to write out a temporary torrc file
en/volunteer.wml  707) and ask the user to manually move it to <code>/etc/tor/torrc</code>,
en/volunteer.wml  708) but that's bad because users shouldn't have to mess with files directly.
en/volunteer.wml  709) <br />
en/volunteer.wml  710) A person undertaking this project should have prior knowledge of
en/volunteer.wml  711) Debian package management and some C++ development experience. Previous
en/volunteer.wml  712) experience with Qt is helpful, but not required.
en/volunteer.wml  713) </li>
en/volunteer.wml  714) -->
en/volunteer.wml  715) 
en/volunteer.wml  716) <!-- This should be mostly done.
en/volunteer.wml  717) <li>
en/volunteer.wml  718) <b>Tor/Polipo/Vidalia Auto-Update Framework</b>
en/volunteer.wml  719) <br />
en/volunteer.wml  720) We're in need of a good authenticated-update framework.
en/volunteer.wml  721) Vidalia already has the ability to notice when the user is running an
en/volunteer.wml  722) outdated or unrecommended version of Tor, using signed statements inside
en/volunteer.wml  723) the Tor directory information. Currently, Vidalia simply pops
en/volunteer.wml  724) up a little message box that lets the user know they should manually
en/volunteer.wml  725) upgrade. The goal of this project would be to extend Vidalia with the
en/volunteer.wml  726) ability to also fetch and install the updated Tor software for the
en/volunteer.wml  727) user. We should do the fetches via Tor when possible, but also fall back
en/volunteer.wml  728) to direct fetches in a smart way. Time permitting, we would also like
en/volunteer.wml  729) to be able to update other
en/volunteer.wml  730) applications included in the bundled installers, such as Polipo and
en/volunteer.wml  731) Vidalia itself.
en/volunteer.wml  732) <br />
en/volunteer.wml  733) To complete this project, the student will first need to first investigate
en/volunteer.wml  734) the existing auto-update frameworks (e.g., Sparkle on OS X) to evaluate
en/volunteer.wml  735) their strengths, weaknesses, security properties, and ability to be
en/volunteer.wml  736) integrated into Vidalia. If none are found to be suitable, the student
en/volunteer.wml  737) will design their own auto-update framework, document the design, and
en/volunteer.wml  738) then discuss the design with other developers to assess any security
en/volunteer.wml  739) issues. The student will then implement their framework (or integrate
en/volunteer.wml  740) an existing one) and test it.
en/volunteer.wml  741) <br />
en/volunteer.wml  742) A person undertaking this project should have good C++ development
en/volunteer.wml  743) experience. Previous experience with Qt is helpful, but not required. One
en/volunteer.wml  744) should also have a good understanding of common security
en/volunteer.wml  745) practices, such as package signature verification. Good writing ability
en/volunteer.wml  746) is also important for this project, since a vital step of the project
en/volunteer.wml  747) will be producing a design document to review and discuss
en/volunteer.wml  748) with others prior to implementation.
en/volunteer.wml  749) </li>
en/volunteer.wml  750) -->
en/volunteer.wml  751) 
en/volunteer.wml  752) <!-- Jake already did most of this.
en/volunteer.wml  753) <li>
en/volunteer.wml  754) <b>Improvements on our active browser configuration tester</b> -
en/volunteer.wml  755) <a href="https://check.torproject.org/">https://check.torproject.org/</a>
en/volunteer.wml  756) <br />
en/volunteer.wml  757) We currently have a functional web page to detect if Tor is working. It
en/volunteer.wml  758) has a few places where it falls short. It requires improvements with
en/volunteer.wml  759) regard to default languages and functionality. It currently only responds
en/volunteer.wml  760) in English. In addition, it is a hack of a perl script that should have
en/volunteer.wml  761) never seen the light of day. It should probably be rewritten in python
en/volunteer.wml  762) with multi-lingual support in mind. It currently uses the <a
en/volunteer.wml  763) href="http://exitlist.torproject.org/">Tor DNS exit list</a>
en/volunteer.wml  764) and should continue to do so in the future. It currently result in certain
en/volunteer.wml  765) false positives and these should be discovered, documented, and fixed
en/volunteer.wml  766) where possible. Anyone working on this project should be interested in
en/volunteer.wml  767) DNS, basic perl or preferably python programming skills, and will have
en/volunteer.wml  768) to interact minimally with Tor to test their code.
en/volunteer.wml  769) <br />
en/volunteer.wml  770) If you want to make the project more exciting
en/volunteer.wml  771) and involve more design and coding, take a look at <a
en/volunteer.wml  772) href="<svnsandbox>doc/spec/proposals/131-verify-tor-usage.txt">proposal
en/volunteer.wml  773) 131-verify-tor-usage.txt</a>.
en/volunteer.wml  774) </li>
en/volunteer.wml  775) -->
en/volunteer.wml  776) 

en/volunteer.wml  777) <!-- If we decide to switch to the exit list in TorStatus, this is obsolete.

en/volunteer.wml  778) <li>

en/volunteer.wml  779) <b>Improvements on our DNS Exit List service</b> -

en/volunteer.wml  780) <a href="http://exitlist.torproject.org/">http://exitlist.torproject.org/</a>

en/volunteer.wml  781) <br />

en/volunteer.wml  782) The <a href="http://p56soo2ibjkx23xo.onion/">exitlist software</a>
en/volunteer.wml  783) is written by our fabulous anonymous

en/volunteer.wml  784) contributer Tup. It's a DNS server written in Haskell that supports part of our <a

en/volunteer.wml  785) href="<svnsandbox>doc/contrib/torel-design.txt">exitlist

en/volunteer.wml  786) design document</a>. Currently, it is functional and it is used by

en/volunteer.wml  787) check.torproject.org and other users. The issues that are outstanding
en/volunteer.wml  788) are mostly aesthetic. This wonderful service could use a much better
en/volunteer.wml  789) website using the common Tor theme. It would be best served with better
en/volunteer.wml  790) documentation for common services that use an RBL. It could use more
en/volunteer.wml  791) publicity. A person working on this project should be interested in DNS,
en/volunteer.wml  792) basic RBL configuration for popular services, and writing documentation.
en/volunteer.wml  793) The person would require minimal Tor interaction — testing their
en/volunteer.wml  794) own documentation at the very least. Furthermore, it would be useful

en/volunteer.wml  795) if they were interested in Haskell and wanted to implement more of the

en/volunteer.wml  796) torel-design.txt suggestions.
en/volunteer.wml  797) </li>

en/volunteer.wml  798) -->

en/volunteer.wml  799) 

en/volunteer.wml  800) <!-- Nobody wanted to keep this.

en/volunteer.wml  801) <li>

en/volunteer.wml  802) <b>Testing integration of Tor with web browsers for our end users</b>

en/volunteer.wml  803) <br />

en/volunteer.wml  804) The Tor project currently lacks a solid test suite to ensure that a
en/volunteer.wml  805) user has a properly and safely configured web browser. It should test for as

en/volunteer.wml  806) many known issues as possible. It should attempt to decloak the

en/volunteer.wml  807) user in any way possible. Two current webpages that track these

en/volunteer.wml  808) kinds of issues are run by Greg Fleischer and HD Moore. Greg keeps a nice <a

en/volunteer.wml  809) href="http://pseudo-flaw.net/tor/torbutton/">list of issues along
en/volunteer.wml  810) with their proof of concept code, bug issues, etc</a>. HD Moore runs

en/volunteer.wml  811) the <a href="http://www.decloak.net/">metasploit

en/volunteer.wml  812) decloak website</a>. A person interested in defending Tor could start

en/volunteer.wml  813) by collecting as many workable and known methods for decloaking a

en/volunteer.wml  814) Tor user. (<a href="https://torcheck.xenobite.eu/">This page</a> may

en/volunteer.wml  815) be helpful as a start.) One should be familiar with the common pitfalls but

en/volunteer.wml  816) possibly have new methods in mind for implementing decloaking issues. The
en/volunteer.wml  817) website should ensure that it tells a user what their problem is. It
en/volunteer.wml  818) should help them to fix the problem or direct them to the proper support

en/volunteer.wml  819) channels. The person should also be closely familiar with using Tor and how

en/volunteer.wml  820) to prevent Tor information leakage.

en/volunteer.wml  821) </li>

en/volunteer.wml  822) -->

en/volunteer.wml  823) 

en/volunteer.wml  824) <!-- Nick did quite some work here. Is this project still required then?

en/volunteer.wml  825) <li>

en/volunteer.wml  826) <b>Libevent and Tor integration improvements</b>
en/volunteer.wml  827) <br />

en/volunteer.wml  828) Tor should make better use of the more recent features of Niels
en/volunteer.wml  829) Provos's <a href="http://monkey.org/~provos/libevent/">Libevent</a>

en/volunteer.wml  830) library.  Tor already uses Libevent for its low-level asynchronous IO

en/volunteer.wml  831) calls, and could also use Libevent's increasingly good implementations

en/volunteer.wml  832) of network buffers and of HTTP.  This wouldn't be simply a matter of

en/volunteer.wml  833) replacing Tor's internal calls with calls to Libevent: instead, we'll

en/volunteer.wml  834) need to refactor Tor to use Libevent calls that do not follow the

en/volunteer.wml  835) same models as Tor's existing backends. Also, we'll need to add
en/volunteer.wml  836) missing functionality to Libevent as needed — most difficult likely
en/volunteer.wml  837) will be adding OpenSSL support on top of Libevent's buffer abstraction.
en/volunteer.wml  838) Also tricky will be adding rate-limiting to Libevent.

en/volunteer.wml  839) </li>

en/volunteer.wml  840) -->

en/volunteer.wml  841) 

en/volunteer.wml  842) <!--

en/volunteer.wml  843) <li>

en/volunteer.wml  844) <b>Improving the Tor QA process: Continuous Integration for Windows builds</b>
en/volunteer.wml  845) <br />

en/volunteer.wml  846) It would be useful to have automated build processes for Windows and
en/volunteer.wml  847) probably other platforms. The purpose of having a continuous integration
en/volunteer.wml  848) build environment is to ensure that Windows isn't left behind for any of
en/volunteer.wml  849) the software projects used in the Tor project or its accompanying.<br />
en/volunteer.wml  850) Buildbot may be a good choice for this as it appears to support all of

en/volunteer.wml  851) the platforms Tor does. See the

en/volunteer.wml  852) <a href="http://en.wikipedia.org/wiki/BuildBot">wikipedia entry for

en/volunteer.wml  853) buildbot</a>.<br />
en/volunteer.wml  854) There may be better options and the person undertaking this task should

en/volunteer.wml  855) evaluate other options. Any person working on this automatic build
en/volunteer.wml  856) process should have experience or be willing to learn how to build all
en/volunteer.wml  857) of the respective Tor related code bases from scratch. Furthermore, the
en/volunteer.wml  858) person should have some experience building software in Windows
en/volunteer.wml  859) environments as this is the target audience we want to ensure we do not
en/volunteer.wml  860) leave behind. It would require close work with the Tor source code but
en/volunteer.wml  861) probably only in the form of building, not authoring.<br />
en/volunteer.wml  862) Additionally, we need to automate our performance testing for all platforms.
en/volunteer.wml  863) We've got buildbot (except on Windows &mdash; as noted above) to automate
en/volunteer.wml  864) our regular integration and compile testing already,
en/volunteer.wml  865) but we need to get our network simulation tests (as built in torflow)
en/volunteer.wml  866) updated for more recent versions of Tor, and designed to launch a test
en/volunteer.wml  867) network either on a single machine, or across several, so we can test
en/volunteer.wml  868) changes in performance on machines in different roles automatically.

en/volunteer.wml  869) </li>

en/volunteer.wml  870) -->

en/volunteer.wml  871) 

en/volunteer.wml  872) <!-- Removed, unless Mike still wants this to be in.

en/volunteer.wml  873) <li>
en/volunteer.wml  874) <b>Torbutton improvements</b>
en/volunteer.wml  875) <br />
en/volunteer.wml  876) Torbutton has a number of improvements that can be made in the post-1.2
en/volunteer.wml  877) timeframe. Most of these are documented as feature requests in the <a

en/volunteer.wml  878) href="https://bugs.torproject.org/flyspray/index.php?tasks=all&project=5">Torbutton

en/volunteer.wml  879) flyspray section</a>. Good examples include: stripping off node.exit on http
en/volunteer.wml  880) headers, more fine-grained control over formfill blocking, improved referrer

en/volunteer.wml  881) spoofing based on the domain of the site (a-la <a

en/volunteer.wml  882) href="https://addons.mozilla.org/en-US/firefox/addon/953">refcontrol extension</a>),

en/volunteer.wml  883) tighter integration with Vidalia for reporting Tor status, a New Identity
en/volunteer.wml  884) button with Tor integration and multiple identity management, and anything

en/volunteer.wml  885) else you might think of.

en/volunteer.wml  886) <br />
en/volunteer.wml  887) This work would be independent coding in Javascript and the fun world of <a
en/volunteer.wml  888) href="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">XUL</a>,
en/volunteer.wml  889) with not too much involvement in the Tor internals.

en/volunteer.wml  890) </li>

en/volunteer.wml  891) -->

en/volunteer.wml  892) 

en/volunteer.wml  893) <!-- Is Blossom development still happening?

en/volunteer.wml  894) <li>
en/volunteer.wml  895) <b>Rework and extend Blossom</b>
en/volunteer.wml  896) <br />
en/volunteer.wml  897) Rework and extend Blossom (a tool for monitoring and
en/volunteer.wml  898) selecting appropriate Tor circuits based upon exit node requirements
en/volunteer.wml  899) specified by the user) to gather data in a self-contained way, with
en/volunteer.wml  900) parameters easily configurable by the user.  Blossom is presently
en/volunteer.wml  901) implemented as a single Python script that interfaces with Tor using the
en/volunteer.wml  902) Controller interface and depends upon metadata about Tor nodes obtained
en/volunteer.wml  903) via external processes, such as a webpage indicating status of the nodes
en/volunteer.wml  904) plus publically available data from DNS, whois, etc.  This project has
en/volunteer.wml  905) two parts: (1) Determine which additional metadata may be useful and
en/volunteer.wml  906) rework Blossom so that it cleanly obtains the metadata on its own rather
en/volunteer.wml  907) than depend upon external scripts (this may, for example, involve
en/volunteer.wml  908) additional threads or inter-process communication), and (2) develop a
en/volunteer.wml  909) means by which the user can easily configure Blossom, starting with a
en/volunteer.wml  910) configuration file and possibly working up to a web configuration engine.

en/volunteer.wml  911) Knowledge of Tor and Python are important; knowledge of
en/volunteer.wml  912) TCP, interprocess communication, and Perl will also be helpful.  An
en/volunteer.wml  913) interest in network neutrality is important as well, since the
en/volunteer.wml  914) principles of evaluating and understanding internet inconsistency are at
en/volunteer.wml  915) the core of the Blossom effort.

en/volunteer.wml  916) </li>
en/volunteer.wml  917) 
en/volunteer.wml  918) <li>
en/volunteer.wml  919) <b>Improve Blossom: Allow users to qualitatively describe exit nodes they desire</b>
en/volunteer.wml  920) <br />
en/volunteer.wml  921) Develop and implement a means of affording Blossom
en/volunteer.wml  922) users the ability to qualitatively describe the exit node that they
en/volunteer.wml  923) want.  The Internet is an inconsistent place: some Tor exit nodes see
en/volunteer.wml  924) the world differently than others.  As presently implemented, Blossom (a
en/volunteer.wml  925) tool for monitoring and selecting appropriate Tor circuits based upon
en/volunteer.wml  926) exit node requirements specified by the user) lacks a sufficiently rich
en/volunteer.wml  927) language to describe how the different vantage points are different.
en/volunteer.wml  928) For example, some exit nodes may have an upstream network that filters
en/volunteer.wml  929) certain kinds of traffic or certain websites.  Other exit nodes may
en/volunteer.wml  930) provide access to special content as a result of their location, perhaps
en/volunteer.wml  931) as a result of discrimination on the part of the content providers
en/volunteer.wml  932) themselves.  This project has two parts: (1) develop a language for
en/volunteer.wml  933) describing characteristics of networks in which exit nodes reside, and
en/volunteer.wml  934) (2) incorporate this language into Blossom so that users can select Tor
en/volunteer.wml  935) paths based upon the description.

en/volunteer.wml  936) Knowledge of Tor and Python are important; knowledge of
en/volunteer.wml  937) TCP, interprocess communication, and Perl will also be helpful.  An
en/volunteer.wml  938) interest in network neutrality is important as well, since the
en/volunteer.wml  939) principles of evaluating and understanding internet inconsistency are at
en/volunteer.wml  940) the core of the Blossom effort.

en/volunteer.wml  941) </li>

en/volunteer.wml  942) -->

en/volunteer.wml  943) 

en/volunteer.wml  944) <!-- not really suited for GSoC; integrated into TBB for Linux/Mac OS X

en/volunteer.wml  945) <li>
en/volunteer.wml  946) <b>Usability testing of Tor</b>
en/volunteer.wml  947) <br />

en/volunteer.wml  948) Priority: <i>Medium</i>
en/volunteer.wml  949) <br />
en/volunteer.wml  950) Effort Level: <i>Medium</i>
en/volunteer.wml  951) <br />
en/volunteer.wml  952) Skill Level: <i>Low to Medium</i>
en/volunteer.wml  953) <br />
en/volunteer.wml  954) Likely Mentors: <i>Andrew</i>
en/volunteer.wml  955) <br />

en/volunteer.wml  956) Especially the browser bundle, ideally amongst our target demographic.
en/volunteer.wml  957) That would help a lot in knowing what needs to be done in terms of bug
en/volunteer.wml  958) fixes or new features. We get this informally at the moment, but a more
en/volunteer.wml  959) structured process would be better.
en/volunteer.wml  960) </li>

en/volunteer.wml  961) -->

en/volunteer.wml  962) 

en/volunteer.wml  963) </ol>
en/volunteer.wml  964) 

en/volunteer.wml  965) <a id="OtherCoding"></a>
en/volunteer.wml  966) <h2><a class="anchor" href="#OtherCoding">Other Coding and Design related ideas</a></h2>

volunteer.html    967) <ol>

en/volunteer.wml  968) <li>Tor relays don't work well on Windows XP. On

en/volunteer.wml  969) Windows, Tor uses the standard <tt>select()</tt> system

en/volunteer.wml  970) call, which uses space in the non-page pool. This means

en/volunteer.wml  971) that a medium sized Tor relay will empty the non-page pool, <a

en/volunteer.wml  972) href="https://wiki.torproject.org/noreply/TheOnionRouter/WindowsBufferProblems">causing

en/volunteer.wml  973) havoc and system crashes</a>. We should probably be using overlapped IO

en/volunteer.wml  974) instead. One solution would be to teach <a
en/volunteer.wml  975) href="http://www.monkey.org/~provos/libevent/">libevent</a> how to use
en/volunteer.wml  976) overlapped IO rather than select() on Windows, and then adapt Tor to

en/volunteer.wml  977) the new libevent interface. Christian King made a

en/volunteer.wml  978) <a href="https://svn.torproject.org/svn/libevent-urz/trunk/">good

en/volunteer.wml  979) start</a> on this in the summer of 2007.</li>

en/volunteer.wml  980) 

en/volunteer.wml  981) <li>We need to actually start building our <a href="<page
en/volunteer.wml  982) documentation>#DesignDoc">blocking-resistance design</a>. This involves

en/volunteer.wml  983) fleshing out the design, modifying many different pieces of Tor, adapting

en/volunteer.wml  984) <a href="<page vidalia/index>">Vidalia</a> so it supports the

en/volunteer.wml  985) new features, and planning for deployment.</li>

en/volunteer.wml  986) 

en/volunteer.wml  987) <li>We need a flexible simulator framework for studying end-to-end
en/volunteer.wml  988) traffic confirmation attacks. Many researchers have whipped up ad hoc
en/volunteer.wml  989) simulators to support their intuition either that the attacks work
en/volunteer.wml  990) really well or that some defense works great. Can we build a simulator
en/volunteer.wml  991) that's clearly documented and open enough that everybody knows it's
en/volunteer.wml  992) giving a reasonable answer? This will spur a lot of new research.
en/volunteer.wml  993) See the entry <a href="#Research">below</a> on confirmation attacks for
en/volunteer.wml  994) details on the research side of this task &mdash; who knows, when it's
en/volunteer.wml  995) done maybe you can help write a paper or three also.</li>

en/volunteer.wml  996) 

en/volunteer.wml  997) <li>Tor 0.1.1.x and later include support for hardware crypto accelerators

en/volunteer.wml  998) via OpenSSL. It has been lightly tested and is possibly very buggy.  We're looking for more rigorous testing, performance analysis, and optimally, code fixes to openssl and Tor if needed.</li>

en/volunteer.wml  999) 

volunteer.html   1000) <li>Perform a security analysis of Tor with <a
volunteer.html   1001) href="http://en.wikipedia.org/wiki/Fuzz_testing">"fuzz"</a>. Determine

en/volunteer.wml 1002) if there are good fuzzing libraries out there for what we want. Win fame by

volunteer.html   1003) getting credit when we put out a new release because of you!</li>

en/volunteer.wml 1004) 

volunteer.html   1005) <li>Tor uses TCP for transport and TLS for link
volunteer.html   1006) encryption. This is nice and simple, but it means all cells
volunteer.html   1007) on a link are delayed when a single packet gets dropped, and
volunteer.html   1008) it means we can only reasonably support TCP streams. We have a <a

en/volunteer.wml 1009) href="https://wiki.torproject.org/noreply/TheOnionRouter/TorFAQ#TransportIPnotTCP">list

en/volunteer.wml 1010) of reasons why we haven't shifted to UDP transport</a>, but it would
en/volunteer.wml 1011) be great to see that list get shorter. We also have a proposed <a

en/volunteer.wml 1012) href="<svnsandbox>doc/spec/proposals/100-tor-spec-udp.txt">specification
en/volunteer.wml 1013) for Tor and

en/volunteer.wml 1014) UDP</a> &mdash; please let us know what's wrong with it.</li>

en/volunteer.wml 1015) 

volunteer.html   1016) <li>We're not that far from having IPv6 support for destination addresses
volunteer.html   1017) (at exit nodes). If you care strongly about IPv6, that's probably the
volunteer.html   1018) first place to start.</li>

en/volunteer.wml 1019) 
en/volunteer.wml 1020) <li>We need a way to generate the website diagrams (for example, the "How
en/volunteer.wml 1021) Tor Works" pictures on the <a href="<page overview>">overview page</a>
en/volunteer.wml 1022) from source, so we can translate them as UTF-8 text rather than edit
en/volunteer.wml 1023) them by hand with Gimp. We might want to
en/volunteer.wml 1024) integrate this as an wml file so translations are easy and images are
en/volunteer.wml 1025) generated in multiple languages whenever we build the website.</li>
en/volunteer.wml 1026) 
en/volunteer.wml 1027) <li>How can we make the <a
en/volunteer.wml 1028) href="http://anonymityanywhere.com/incognito/">Incognito LiveCD</a>
en/volunteer.wml 1029) easier to maintain, improve, and document?</li>

volunteer.html   1030) </ol>
volunteer.html   1031) 

en/volunteer.wml 1032) <a id="Research"></a>
en/volunteer.wml 1033) <h2><a class="anchor" href="#Research">Research</a></h2>

volunteer.html   1034) <ol>

volunteer.html   1035) <li>The "website fingerprinting attack": make a list of a few
volunteer.html   1036) hundred popular websites, download their pages, and make a set of
volunteer.html   1037) "signatures" for each site. Then observe a Tor client's traffic. As
volunteer.html   1038) you watch him receive data, you quickly approach a guess about which
volunteer.html   1039) (if any) of those sites he is visiting. First, how effective is
volunteer.html   1040) this attack on the deployed Tor codebase? Then start exploring
volunteer.html   1041) defenses: for example, we could change Tor's cell size from 512
volunteer.html   1042) bytes to 1024 bytes, we could employ padding techniques like <a
volunteer.html   1043) href="http://freehaven.net/anonbib/#timing-fc2004">defensive dropping</a>,
volunteer.html   1044) or we could add traffic delays. How much of an impact do these have,
volunteer.html   1045) and how much usability impact (using some suitable metric) is there from
volunteer.html   1046) a successful defense in each case?</li>

volunteer.html   1047) <li>The "end-to-end traffic confirmation attack":
volunteer.html   1048) by watching traffic at Alice and at Bob, we can <a
volunteer.html   1049) href="http://freehaven.net/anonbib/#danezis:pet2004">compare
volunteer.html   1050) traffic signatures and become convinced that we're watching the same
volunteer.html   1051) stream</a>. So far Tor accepts this as a fact of life and assumes this
volunteer.html   1052) attack is trivial in all cases. First of all, is that actually true? How
volunteer.html   1053) much traffic of what sort of distribution is needed before the adversary
volunteer.html   1054) is confident he has won? Are there scenarios (e.g. not transmitting much)
volunteer.html   1055) that slow down the attack? Do some traffic padding or traffic shaping
volunteer.html   1056) schemes work better than others?</li>

en/volunteer.wml 1057) <li>A related question is: Does running a relay/bridge provide additional
en/volunteer.wml 1058) protection against these timing attacks? Can an external adversary that can't

en/volunteer.wml 1059) see inside TLS links still recognize individual streams reliably?

en/volunteer.wml 1060) Does the amount of traffic carried degrade this ability any? What if the
en/volunteer.wml 1061) client-relay deliberately delayed upstream relayed traffic to create a queue
en/volunteer.wml 1062) that could be used to mimic timings of client downstream traffic to make it
en/volunteer.wml 1063) look like it was also relayed? This same queue could also be used for masking
en/volunteer.wml 1064) timings in client upstream traffic with the techniques from <a
en/volunteer.wml 1065) href="http://www.freehaven.net/anonbib/#ShWa-Timing06">adaptive padding</a>,
en/volunteer.wml 1066) but without the need for additional traffic. Would such an interleaving of
en/volunteer.wml 1067) client upstream traffic obscure timings for external adversaries? Would the
en/volunteer.wml 1068) strategies need to be adjusted for asymmetric links? For example, on
en/volunteer.wml 1069) asymmetric links, is it actually possible to differentiate client traffic from
en/volunteer.wml 1070) natural bursts due to their asymmetric capacity? Or is it easier than
en/volunteer.wml 1071) symmetric links for some other reason?</li>

en/volunteer.wml 1072) <li>Repeat Murdoch and Danezis's <a
en/volunteer.wml 1073) href="http://www.cl.cam.ac.uk/~sjm217/projects/anon/#torta">attack from
en/volunteer.wml 1074) Oakland 05</a> on the current Tor network. See if you can learn why it
en/volunteer.wml 1075) works well on some nodes and not well on others. (My theory is that the
en/volunteer.wml 1076) fast nodes with spare capacity resist the attack better.) If that's true,
en/volunteer.wml 1077) then experiment with the RelayBandwidthRate and RelayBandwidthBurst
en/volunteer.wml 1078) options to run a relay that is used as a client while relaying the
en/volunteer.wml 1079) attacker's traffic: as we crank down the RelayBandwidthRate, does the
en/volunteer.wml 1080) attack get harder? What's the right ratio of RelayBandwidthRate to
en/volunteer.wml 1081) actually capacity? Or is it a ratio at all? While we're at it, does a
en/volunteer.wml 1082) much larger set of candidate relays increase the false positive rate
en/volunteer.wml 1083) or other complexity for the attack? (The Tor network is now almost two
en/volunteer.wml 1084) orders of magnitude larger than it was when they wrote their paper.) Be
en/volunteer.wml 1085) sure to read <a href="http://freehaven.net/anonbib/#clog-the-queue">Don't
en/volunteer.wml 1086) Clog the Queue</a> too.</li>

volunteer.html   1087) <li>The "routing zones attack": most of the literature thinks of
volunteer.html   1088) the network path between Alice and her entry node (and between the
volunteer.html   1089) exit node and Bob) as a single link on some graph. In practice,
volunteer.html   1090) though, the path traverses many autonomous systems (ASes), and <a
volunteer.html   1091) href="http://freehaven.net/anonbib/#feamster:wpes2004">it's not uncommon
volunteer.html   1092) that the same AS appears on both the entry path and the exit path</a>.
volunteer.html   1093) Unfortunately, to accurately predict whether a given Alice, entry,
volunteer.html   1094) exit, Bob quad will be dangerous, we need to download an entire Internet
volunteer.html   1095) routing zone and perform expensive operations on it. Are there practical
volunteer.html   1096) approximations, such as avoiding IP addresses in the same /8 network?</li>

en/volunteer.wml 1097) <li>Other research questions regarding geographic diversity consider
en/volunteer.wml 1098) the tradeoff between choosing an efficient circuit and choosing a random

en/volunteer.wml 1099) circuit. Look at Stephen Rollyson's <a

en/volunteer.wml 1100) href="http://swiki.cc.gatech.edu:8080/ugResearch/uploads/7/ImprovingTor.pdf">position
en/volunteer.wml 1101) paper</a> on how to discard particularly slow choices without hurting

en/volunteer.wml 1102) anonymity "too much". This line of reasoning needs more work and more
en/volunteer.wml 1103) thinking, but it looks very promising.</li>

en/volunteer.wml 1104) <li>Tor doesn't work very well when relays have asymmetric bandwidth

volunteer.html   1105) (e.g. cable or DSL). Because Tor has separate TCP connections between
volunteer.html   1106) each hop, if the incoming bytes are arriving just fine and the outgoing
volunteer.html   1107) bytes are all getting dropped on the floor, the TCP push-back mechanisms
volunteer.html   1108) don't really transmit this information back to the incoming streams.
volunteer.html   1109) Perhaps Tor should detect when it's dropping a lot of outgoing packets,
volunteer.html   1110) and rate-limit incoming streams to regulate this itself? I can imagine
volunteer.html   1111) a build-up and drop-off scheme where we pick a conservative rate-limit,
volunteer.html   1112) slowly increase it until we get lost packets, back off, repeat. We
volunteer.html   1113) need somebody who's good with networks to simulate this and help design
volunteer.html   1114) solutions; and/or we need to understand the extent of the performance
volunteer.html   1115) degradation, and use this as motivation to reconsider UDP transport.</li>
volunteer.html   1116) <li>A related topic is congestion control. Is our
volunteer.html   1117) current design sufficient once we have heavy use? Maybe
volunteer.html   1118) we should experiment with variable-sized windows rather
volunteer.html   1119) than fixed-size windows? That seemed to go well in an <a
volunteer.html   1120) href="http://www.psc.edu/networking/projects/hpn-ssh/theory.php">ssh
volunteer.html   1121) throughput experiment</a>. We'll need to measure and tweak, and maybe
volunteer.html   1122) overhaul if the results are good.</li>

en/volunteer.wml 1123) <li>Our censorship-resistance goals include preventing
en/volunteer.wml 1124) an attacker who's looking at Tor traffic on the wire from <a

en/volunteer.wml 1125) href="<svnsandbox>doc/design-paper/blocking.html#sec:network-fingerprint">distinguishing

en/volunteer.wml 1126) it from normal SSL traffic</a>. Obviously we can't achieve perfect
en/volunteer.wml 1127) steganography and still remain usable, but for a first step we'd like to
en/volunteer.wml 1128) block any attacks that can win by observing only a few packets. One of
en/volunteer.wml 1129) the remaining attacks we haven't examined much is that Tor cells are 512
en/volunteer.wml 1130) bytes, so the traffic on the wire may well be a multiple of 512 bytes.
en/volunteer.wml 1131) How much does the batching and overhead in TLS records blur this on the
en/volunteer.wml 1132) wire? Do different buffer flushing strategies in Tor affect this? Could
en/volunteer.wml 1133) a bit of padding help a lot, or is this an attack we must accept?</li>

volunteer.html   1134) <li>Tor circuits are built one hop at a time, so in theory we have the
volunteer.html   1135) ability to make some streams exit from the second hop, some from the
volunteer.html   1136) third, and so on. This seems nice because it breaks up the set of exiting

en/volunteer.wml 1137) streams that a given relay can see. But if we want each stream to be safe,

volunteer.html   1138) the "shortest" path should be at least 3 hops long by our current logic, so
volunteer.html   1139) the rest will be even longer. We need to examine this performance / security
volunteer.html   1140) tradeoff.</li>

en/volunteer.wml 1141) <li>It's not that hard to DoS Tor relays or directory authorities. Are client

volunteer.html   1142) puzzles the right answer? What other practical approaches are there? Bonus
volunteer.html   1143) if they're backward-compatible with the current Tor protocol.</li>

en/volunteer.wml 1144) <li>Programs like <a

en/volunteer.wml 1145) href="<page torbutton/index>">Torbutton</a> aim to hide

en/volunteer.wml 1146) your browser's UserAgent string by replacing it with a uniform answer for
en/volunteer.wml 1147) every Tor user. That way the attacker can't splinter Tor's anonymity set
en/volunteer.wml 1148) by looking at that header. It tries to pick a string that is commonly used
en/volunteer.wml 1149) by non-Tor users too, so it doesn't stand out. Question one: how badly
en/volunteer.wml 1150) do we hurt ourselves by periodically updating the version of Firefox
en/volunteer.wml 1151) that Torbutton claims to be? If we update it too often, we splinter the
en/volunteer.wml 1152) anonymity sets ourselves. If we don't update it often enough, then all the
en/volunteer.wml 1153) Tor users stand out because they claim to be running a quite old version
en/volunteer.wml 1154) of Firefox. The answer here probably depends on the Firefox versions seen
en/volunteer.wml 1155) in the wild. Question two: periodically people ask us to cycle through N
en/volunteer.wml 1156) UserAgent strings rather than stick with one. Does this approach help,
en/volunteer.wml 1157) hurt, or not matter? Consider: cookies and recognizing Torbutton users
en/volunteer.wml 1158) by their rotating UserAgents; malicious websites who only attack certain
en/volunteer.wml 1159) browsers; and whether the answers to question one impact this answer.
en/volunteer.wml 1160) </li>

en/volunteer.wml 1161) <li>Right now Tor clients are willing to reuse a given circuit for ten
en/volunteer.wml 1162) minutes after it's first used. The goal is to avoid loading down the
en/volunteer.wml 1163) network with too many circuit extend operations, yet to also avoid having
en/volunteer.wml 1164) clients use the same circuit for so long that the exit node can build a
en/volunteer.wml 1165) useful pseudonymous profile of them. Alas, ten minutes is probably way
en/volunteer.wml 1166) too long, especially if connections from multiple protocols (e.g. IM and
en/volunteer.wml 1167) web browsing) are put on the same circuit. If we keep fixed the overall
en/volunteer.wml 1168) number of circuit extends that the network needs to do, are there more
en/volunteer.wml 1169) efficient and/or safer ways for clients to allocate streams to circuits,
en/volunteer.wml 1170) or for clients to build preemptive circuits? Perhaps this research item
en/volunteer.wml 1171) needs to start with gathering some traces of what connections typical
en/volunteer.wml 1172) clients try to launch, so you have something realistic to try to optimize.
en/volunteer.wml 1173) </li>
en/volunteer.wml 1174) <li>How many bridge relays do you need to know to maintain
en/volunteer.wml 1175) reachability? We should measure the churn in our bridges. If there is
en/volunteer.wml 1176) lots of churn, are there ways to keep bridge users more likely to stay
en/volunteer.wml 1177) connected?
en/volunteer.wml 1178) </li>

volunteer.html   1179) </ol>
volunteer.html   1180) 

en/volunteer.wml 1181) <p>

en/volunteer.wml 1182) <a href="<page contact>">Let us know</a> if you've made progress on any
en/volunteer.wml 1183) of these!

en/volunteer.wml 1184) </p>

volunteer.html   1185) 

en/volunteer.wml 1186)   </div><!-- #main -->

volunteer.html   1187) 

en/volunteer.wml 1188) #include <foot.wmi>