tor-webwml.git

1) ## translation metadata

2) # Revision: $Revision$

3) # Translation-Priority: 4-optional
4) 
5) #include "head.wmi" TITLE="Tor: Volunteer" CHARSET="UTF-8"
6) <div id="content" class="clearfix">
7)   <div id="breadcrumbs">

8)     <a href="<page index>">Home &raquo; </a>

9)     <a href="<page getinvolved/volunteer>">Volunteer</a>
10)   </div>
11)   <div id="maincol"> 
12)     <!-- PUT CONTENT AFTER THIS TAG -->
13)     <h1>A few things everyone can do now:</h1>
14)     <ol>
15)     <li>Please consider <a href="<page docs/tor-doc-relay>">running
16)     a relay</a> to help the Tor network grow.</li>

17)     <li>Do you have an Amazon account? Are you willing to spend up to $3 a

18)     month? Then spin up your own Tor <a href="<page
19)     docs/bridges>">bridge</a> in less than 10 minutes with <a

20)     href="https://cloud.torproject.org/">tor cloud</a>!</li>

21)     <li>Tell your friends! Get them to run relays. Get them to run hidden
22)     services. Get them to tell their friends.</li>
23)     <li>If you like Tor's goals, please <a href="<page donate/donate>">take a moment
24)     to donate to support further Tor development</a>. We're also looking
25)     for more sponsors &mdash; if you know any companies, NGOs, agencies,
26)     or other organizations that want anonymity / privacy / communications
27)     security, let them know about us.</li>
28)     <li>We're looking for more <a href="<page about/torusers>">good examples of Tor
29)     users and Tor use cases</a>. If you use Tor for a scenario or purpose not
30)     yet described on that page, and you're comfortable sharing it with us,
31)     we'd love to hear from you.</li>
32)     </ol>
33)     
34)     <a id="Documentation"></a>
35)     <h2><a class="anchor" href="#Documentation">Documentation</a></h2>
36)     <ol>
37)     <li>Help translate the web page and documentation into other
38)     languages. See the <a href="<page getinvolved/translation>">translation
39)     guidelines</a> if you want to help out. We especially need Arabic or
40)     Farsi translations, for the many Tor users in censored areas.</li>
41)     <li>Evaluate and document

42)     <a href="<wiki>doc/TorifyHOWTO">our

43)     list of programs</a> that can be configured to use Tor.</li>
44)     <li>We have a huge list of <a

45)     href="<wiki>doc/SupportPrograms">potentially useful

46)     programs that interface to Tor</a>. Which ones are useful in which
47)     situations? Please help us test them out and document your results.</li>
48)     </ol>
49)     
50)     <a id="Advocacy"></a>
51)     <h2><a class="anchor" href="#Advocacy">Advocacy</a></h2>
52)     <ol>

53)     <li>Create a presentation that can be used for various user group
54) meetings around the world.</li>

55)     <li>Create a video about the positive uses of Tor, what Tor is,
56)     or how to use it.  Some have already started on <a

57)     href="https://media.torproject.org/video/">Tor's Media server</a>,

58)     <a

59)     href="http://www.howcast.com/videos/90601-How-To-Circumvent-an-Internet-Proxy">Howcast</a>,

60)     and <a href="http://www.youtube.com/thetorproject">YouTube</a>.</li> 

61)     <li>Create a poster, or a set of posters, around a theme,

62)     such as "Tor for Freedom!".</li>

63)     <li>Create a t-shirt design that incorporates "Congratulations!
64)     You are using Tor!" in any language.</li>

65)     </ol>
66)     

67)     <a id="Projects"></a>
68)     <h2><a class="anchor" href="#Projects">Projects</a></h2>
69)     
70)     <p>
71)     Below are a list of Tor related projects we're developing and/or
72)     maintaining. Most discussions happen on IRC so if you're interested in any
73)     of these (or you have a project idea of your own), then please <a

74)     href="<page about/contact>#irc">join us in #tor-dev</a>. Don't be shy
75)     to ask questions, and don't hesitate to ask even if the main contributors
76)     aren't active at that moment.

77)     </p>
78)     
79)     <table id="projects">
80)       <tr>
81)         <th>Name</th>
82)         <th>Category</th>
83)         <th>Language</th>
84)         <th>Activity</th>
85)         <th>Contributors</th>
86)       </tr>
87)       
88)       <tr>
89)         <td><a href="#project-tor">Tor</a></td>
90)         <td>Core</td>
91)         <td>C</td>
92)         <td>Heavy</td>

93)         <td>nickm, arma, Sebastian</td>

94)       </tr>
95)       
96)       <tr class="alt">

97)         <td>*<a href="#project-jtor">JTor</a></td>
98)         <td>Core</td>
99)         <td>Java</td>
100)         <td>None</td>
101)         <td></td>
102)       </tr>
103)       
104)       <tr>

105)         <td><a href="#project-tbb">TBB</a></td>
106)         <td>Usability</td>

107)         <td>Sys Admin</td>
108)         <td>Moderate</td>

109)         <td>Erinn</td>

110)       </tr>
111)       

112)       <tr class="alt">

113)         <td><a href="#project-tails">Tails</a></td>

114)         <td>Usability</td>

115)         <td>Sys Admin</td>

116)         <td>Heavy</td>

117)         <td><a href="https://tails.boum.org/chat/">#tails</a></td>

118)       </tr>
119)       

120)       <tr>

121)         <td><a href="#project-torsocks">Torsocks</a></td>
122)         <td>Usability</td>
123)         <td>C</td>

124)         <td>None</td>

125)         <td>mwenge</td>
126)       </tr>
127)       

128)       <tr class="alt">

129)         <td>*<a href="#project-torouter">Torouter</a></td>
130)         <td>Usability</td>

131)         <td>Sys Admin</td>

132)         <td>Light</td>
133)         <td>ioerror, Runa</td>
134)       </tr>
135)       

136)       <tr>

137)         <td><a href="#project-vidalia">Vidalia</a></td>
138)         <td>User Interface</td>
139)         <td>C++, Qt</td>
140)         <td>Light</td>
141)         <td>chiiph</td>
142)       </tr>
143)       

144)       <tr class="alt">

145)         <td><a href="#project-arm">Arm</a></td>
146)         <td>User Interface</td>
147)         <td>Python, Curses</td>

148)         <td>Light</td>

149)         <td>atagar</td>
150)       </tr>
151)       

152)       <tr>

153)         <td><a href="#project-orbot">Orbot</a></td>
154)         <td>User Interface</td>
155)         <td>Java</td>

156)         <td>Moderate</td>

157)         <td>n8fr8</td>
158)       </tr>
159)       

160)       <tr class="alt">

161)         <td><a href="#project-torbutton">Torbutton</a></td>
162)         <td>Browser Add-on</td>
163)         <td>Javascript</td>
164)         <td>Moderate</td>
165)         <td>mikeperry</td>
166)       </tr>
167)       

168)       <tr>

169)         <td><a href="#project-obfsproxy">Obfsproxy</a></td>
170)         <td>Client Add-on</td>
171)         <td>C</td>
172)         <td>Moderate</td>
173)         <td>nickm, asn</td>
174)       </tr>
175)       
176)       <tr class="alt">

177)         <td>*<a href="#project-thandy">Thandy</a></td>
178)         <td>Updater</td>
179)         <td>Python</td>
180)         <td>Light</td>

181)         <td>chiiph, Erinn, nickm</td>

182)       </tr>
183)       

184)       <tr>

185)         <td>*<a href="#project-ooni-probe">Ooni Probe</a></td>
186)         <td>Scanner</td>
187)         <td>Python</td>
188)         <td>Moderate</td>
189)         <td>hellais, ioerror</td>
190)       </tr>
191)       
192)       <tr class="alt">

193)         <td><a href="#project-shadow">Shadow</a></td>
194)         <td>Experimentation</td>
195)         <td>C, Python</td>
196)         <td>Moderate</td>
197)         <td>robgjansen</td>
198)       </tr>
199)       
200)       <tr>

201)         <td><a href="#project-torctl">TorCtl</a></td>
202)         <td>Library</td>
203)         <td>Python</td>
204)         <td>Light</td>
205)         <td>mikeperry</td>
206)       </tr>
207)       

208)       <tr class="alt">

209)         <td>*<a href="#project-stem">Stem</a></td>
210)         <td>Library</td>
211)         <td>Python</td>
212)         <td>Heavy</td>
213)         <td>atagar</td>
214)       </tr>
215)       

216)       <tr>

217)         <td><a href="#project-metrics">Metrics</a></td>
218)         <td>Client Service</td>
219)         <td>Java</td>
220)         <td>Heavy</td>
221)         <td>karsten</td>
222)       </tr>
223)       

224)       <tr class="alt">

225)         <td><a href="#project-torstatus">TorStatus</a></td>
226)         <td>Client Service</td>

227)         <td>Python, Django</td>

228)         <td>None</td>
229)         <td></td>
230)       </tr>
231)       

232)       <tr>

233)         <td><a href="#project-weather">Weather</a></td>
234)         <td>Client Service</td>
235)         <td>Python</td>

236)         <td>None</td>

237)         <td>kaner</td>
238)       </tr>
239)       

240)       <tr class="alt">

241)         <td><a href="#project-gettor">GetTor</a></td>
242)         <td>Client Service</td>
243)         <td>Python</td>

244)         <td>None</td>

245)         <td>kaner</td>

246)       </tr>
247)       

248)       <tr>

249)         <td><a href="#project-torcheck">TorCheck</a></td>
250)         <td>Client Service</td>
251)         <td>Python, Perl</td>
252)         <td>None</td>
253)         <td></td>
254)       </tr>
255)       

256)       <tr class="alt">

257)         <td><a href="#project-bridgedb">BridgeDB</a></td>
258)         <td>Backend Service</td>
259)         <td>Python</td>

260)         <td>None</td>

261)         <td>kaner, nickm</td>

262)       </tr>
263)       

264)       <tr>

265)         <td><a href="#project-torflow">TorFlow</a></td>
266)         <td>Backend Service</td>
267)         <td>Python</td>

268)         <td>Moderate</td>

269)         <td>mikeperry</td>
270)       </tr>
271)       

272)       <tr class="alt">

273)         <td>*<a href="#project-torbel">TorBEL</a></td>
274)         <td>Backend Service</td>
275)         <td>Python</td>
276)         <td>None</td>
277)         <td>Sebastian</td>
278)       </tr>
279)     </table>
280)     
281)     <sub>
282)     * Project is still in an alpha state.
283)     </sub>
284)     
285)     <br /><br />
286)     
287)     <a id="project-tor"></a>
288)     <h3>Tor (<a href="https://gitweb.torproject.org/tor.git">code</a>, <a
289)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Tor+Client&component=Tor+Relay&component=vidalia&order=priority">bug
290)     tracker</a>)</h3>
291)     
292)     <p>
293)     Central project, providing the core software for using and participating in
294)     the Tor network. Numerous people contribute to the project to varying
295)     extents, but the chief architects are Nick Mathewson and Roger Dingledine.
296)     </p>
297)     
298)     <p>
299)     <b>Project Ideas:</b><br />
300)     <i><a href="#resistCensorship">Improving Tor's ability to resist

301)     censorship</a></i>

302)     </p>
303)     

304)     <a id="project-jtor"></a>
305)     <h3><a href="https://github.com/brl/JTor/wiki">JTor</a> (<a
306)     href="https://github.com/brl/JTor">code</a>, <a
307)     href="https://github.com/brl/JTor/issues">bug
308)     tracker</a>)</h3>
309)     
310)     <p>
311)     Java implementation of Tor and successor to <a
312)     href="http://onioncoffee.sourceforge.net/">OnionCoffee</a>. This project
313)     isn't yet complete, and has been inactive since Fall 2010.
314)     </p>
315)     

316)     <a id="project-tbb"></a>
317)     <h3><a href="<page projects/torbrowser>">Tor Browser Bundle</a> (<a
318)     href="https://gitweb.torproject.org/torbrowser.git">code</a>, <a
319)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Tor+bundles/installation&order=priority">bug
320)     tracker</a>)</h3>
321)     
322)     <p>
323)     The Tor Browser Bundle is an easy-to-use portable package of Tor, Vidalia,
324)     and Firefox preconfigured to work together out of the box. This is actively
325)     being worked on by Erinn Clark.
326)     </p>
327)     
328)     <p>
329)     <b>Project Ideas:</b><br />
330)     <i><a href="#auditTBB">Audit Tor Browser Bundles for data leaks</a></i><br />
331)     <i><a href="#usabilityTesting">Usability testing of Tor</a></i>
332)     </p>
333)     

334)     <a id="project-tails"></a>

335)     <h3><a href="https://tails.boum.org/">The Amnesic Incognito Live System</a> (<a

336)     href="http://git.immerda.ch/?p=amnesia.git;a=summary">code</a>, <a

337)     href="https://tails.boum.org/bugs/">bug

338)     tracker</a>)</h3>
339)     
340)     <p>

341)     The Amnesic Incognito Live System is a live CD/USB distribution

342)     preconfigured so that everything is safely routed through Tor and leaves no
343)     trace on the local system. This is a merger of the Amnesia and <a
344)     href="http://www.anonymityanywhere.com/incognito/">Incognito</a> projects,
345)     and still under very active development.
346)     </p>
347)     

348)     <p>
349)     <b>Project Ideas:</b><br />

350)     <i><a href="#tailsHiddenServicePetnames">Petname system for Tor hidden
351)     services</a></i><br />
352)     <i><a href="#tailsServer">Tails server: Self-hosted services behind
353)     Tails-powered Tor hidden services</a></i>

354)     </p>
355)     

356)     <a id="project-torsocks"></a>
357)     <h3><a href="http://code.google.com/p/torsocks/">Torsocks</a> (<a
358)     href="https://gitweb.torproject.org/torsocks.git">code</a>, <a
359)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torify&order=priority">bug
360)     tracker</a>)</h3>
361)     
362)     <p>
363)     Utility for adapting other applications to work with Tor. Development has
364)     slowed and compatibility issues remain with some platforms, but it's
365)     otherwise feature complete.
366)     </p>
367)     

368)     <!--

369)     <p>
370)     <b>Project Ideas:</b><br />
371)     <i><a href="#torsocksForOSX">Make torsocks/dsocks work on OS X</a></i>
372)     </p>

373)     -->

374)     
375)     <a id="project-torouter"></a>
376)     <h3><a

377)     href="<wiki>doc/Torouter">Torouter</a> (<a

378)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torouter&order=priority">bug
379)     tracker</a>)</h3>
380)     
381)     <p>
382)     Project to provide an easy-to-use, embedded Tor instance for routers. This

383)     had high activity in late 2010, but has since been rather quiet.

384)     </p>
385)     
386)     <a id="project-vidalia"></a>
387)     <h3><a href="<page projects/vidalia>">Vidalia</a> (<a

388)     href="https://gitweb.torproject.org/vidalia.git">code</a>, <a

389)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Vidalia&order=priority">bug
390)     tracker</a>)</h3>
391)     
392)     <p>
393)     The most commonly used user interface for Tor. Matt Edman started the
394)     project in 2006 and brought it to its current stable state. Development
395)     slowed for several years, though Tomás Touceda has since taken a lead with
396)     pushing the project forward.
397)     </p>
398)     
399)     <p>
400)     <b>Project Ideas:</b><br />

401)     <i><a href="#vidaliaStatusEventInterface">Tor Controller Status Event Interface for Vidalia</a></i><br />
402)     <i><a href="#vidalia-hidden-service-panel">Torrc plugin and improved hidden service configuration panel</a></i>

403)     </p>
404)     
405)     <a id="project-arm"></a>
406)     <h3><a href="http://www.atagar.com/arm/">Arm</a> (<a

407)     href="https://gitweb.torproject.org/arm.git">code</a>, <a

408)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=arm&order=priority">bug
409)     tracker</a>)</h3>
410)     
411)     <p>
412)     Command-line monitor for Tor. This has been under very active development
413)     by its author, Damian Johnson, since early 2009 to make it a better
414)     general-purpose controller for *nix environments.
415)     </p>
416)     

417)     <!--

418)     <p>
419)     <b>Project Ideas:</b><br />

420)     <i><a href="#armClientMode">Client Mode Use Cases for Arm</a></i><br />
421)     <i><a href="#armGui">GUI for Arm</a></i>

422)     </p>

423)     -->

424)     
425)     <a id="project-orbot"></a>
426)     <h3><a href="https://guardianproject.info/apps/orbot/">Orbot</a> (<a

427)     href="https://gitweb.torproject.org/orbot.git">code</a>, <a

428)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Orbot&order=priority">bug
429)     tracker</a>)</h3>
430)     
431)     <p>
432)     Provides Tor on the Android platform. This was under very active
433)     development up through Fall 2010, after which things have been quiet.
434)     </p>
435)     
436)     <p>
437)     <b>Project Ideas:</b><br />

438)     <i><a href="#orbot-torbutton">TorButton for Mobile Firefox 4 or Custom Browser on Android</a></i><br />
439)     <i><a href="#orbot-userInterface">Build a better user interface for Orbot</a></i><br />

440)     <i><a href="#orbot-optimisation">Core Tor mobile optimisation</a></i>

441)     </p>
442)     
443)     <a id="project-torbutton"></a>
444)     <h3><a href="<page torbutton/index>">Torbutton</a> (<a
445)     href="https://gitweb.torproject.org/torbutton.git">code</a>, <a
446)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torbutton&order=priority">bug
447)     tracker</a>)</h3>
448)     
449)     <p>
450)     Firefox addon that addresses many of the client-side threats to browsing
451)     the Internet anonymously. Mike has since continued to adapt it to new
452)     threats, updated versions of Firefox, and possibly <a
453)     href="https://blog.torproject.org/blog/google-chrome-incognito-mode-tor-and-fingerprinting">Chrome
454)     as well</a>.
455)     </p>
456)     
457)     <p>
458)     <b>Project Ideas:</b><br />
459)     <i><a href="#torbuttonForThunderbird">Torbutton equivalent for Thunderbird</a></i>
460)     </p>
461)     

462)     <a id="project-obfsproxy"></a>
463)     <h3><a href="https://gitweb.torproject.org/obfsproxy.git/tree/HEAD:/doc">Obfsproxy</a> (<a
464)     href="https://gitweb.torproject.org/obfsproxy.git">code</a>, <a
465)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Pluggable+transport&order=priority">bug
466)     tracker</a>)</h3>
467)     
468)     <p>
469)     A proxy that shapes Tor traffic, making it harder for censors to detect and
470)     block Tor.
471)     </p>
472)     

473)     <p>
474)     <b>Project Ideas:</b><br />
475)     <i><a href="#obfsproxy-new-transports">New and innovative pluggable transports</a></i><br />
476)     <i><a href="#obfsproxy-scanning-measures">Defensive bridge active scanning measures</a></i><br />
477)     <i><a href="#obfsproxy-fuzzer">Fuzzer for the Tor protocol</a></i>
478)     </p>
479)     

480)     <a id="project-thandy"></a>
481)     <h3>Thandy (<a
482)     href="https://gitweb.torproject.org/thandy.git">code</a>)</h3>
483)     
484)     <p>
485)     Updater for Tor. The project began in the Summer of 2008 but wasn't
486)     completed. Recently interest in it has been rekindled and many aspects of
487)     its design (including the language it'll be in) are currently in flux.
488)     </p>
489)     

490)     <a id="project-ooni-probe"></a>
491)     <h3>Ooni Probe (<a
492)     href="https://gitweb.torproject.org/ooni-probe.git">code</a>, <a
493)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Ooni&order=priority">bug
494)     tracker</a>)</h3>
495)     
496)     <p>
497)     Censorship scanner, checking your local connection for blocked or modified
498)     content.
499)     </p>
500)     

501)     <a id="project-shadow"></a>
502)     <h3><a href="https://shadow.cs.umn.edu/">Shadow</a> (<a
503)     href="https://github.com/shadow">code</a>, <a
504)     href="https://github.com/shadow/shadow/issues">bug
505)     tracker</a>)</h3>
506)     
507)     <p>
508)     Shadow is a discrete-event network simulator that runs the real
509)     Tor software as a plug-in. Shadow is open-source software that enables
510)     accurate, efficient, controlled, and repeatable Tor experimentation.
511)     </p>
512)     

513)     <a id="project-torctl"></a>
514)     <h3>TorCtl (<a
515)     href="https://gitweb.torproject.org/pytorctl.git">code</a>, <a
516)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torctl&order=priority">bug
517)     tracker</a>)</h3>
518)     
519)     <p>
520)     Python bindings and utilities for using the Tor control port. It has been
521)     stable for several years, with only minor revisions.
522)     </p>
523)     

524)     <a id="project-stem"></a>
525)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/doc/stem">Stem</a> (<a
526)     href="https://gitweb.torproject.org/stem.git">code</a>, <a
527)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Stem&order=priority">bug
528)     tracker</a>)</h3>
529)     
530)     <p>
531)     Python controller library with a similar scope to TorCtl, but with better
532)     testing, documentation, and API. This project is not yet feature complete.
533)     </p>
534)     

535)     <p>
536)     <b>Project Ideas:</b><br />
537)     <i><a href="#stemPathsupport">Stem PathSupport Capabilities</a></i>
538)     </p>
539)     

540)     <a id="project-metrics"></a>
541)     <h3><a href="https://metrics.torproject.org/">Metrics</a> (code: <a
542)     href="https://gitweb.torproject.org/metrics-db.git">db</a>, <a
543)     href="https://gitweb.torproject.org/metrics-utils.git">utils</a>, <a
544)     href="https://gitweb.torproject.org/metrics-web.git">web</a>, <a
545)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Metrics&order=priority">bug
546)     tracker</a>)</h3>
547)     
548)     <p>
549)     Processing and analytics of consensus data, provided to users via the
550)     metrics portal. This has been under active development for several years by
551)     Karsten Loesing.
552)     </p>
553)     

554)     <p>
555)     <b>Project Ideas:</b><br />
556)     <i><a href="#metricsSearch">Searchable Tor descriptor and Metrics data archive</a></i> (Python/Django?)
557)     </p>
558)     

559)     <a id="project-torstatus"></a>
560)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/projects/TorStatus">TorStatus</a> (<a

561)     href="https://gitweb.torproject.org/torstatus.git">code</a>)</h3>

562)     
563)     <p>
564)     Portal providing an overview of the Tor network, and details on any of its
565)     current relays. Though very actively used, this project has been

566)     unmaintained for a long while. The <a
567)     href="https://svn.torproject.org/svn/torstatus/trunk/">original
568)     codebase</a> was written in PHP, and students from Wesleyan wrote the new
569)     Django counterpart.

570)     </p>
571)     
572)     <a id="project-weather"></a>
573)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/projects/Weather">Weather</a> (<a
574)     href="https://gitweb.torproject.org/weather.git">code</a>, <a
575)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Tor+Weather&order=priority">bug
576)     tracker</a>)</h3>
577)     
578)     <p>
579)     Provides automatic notification to subscribed relay operators when their
580)     relay's unreachable. This underwent a rewrite by the <a
581)     href="http://hfoss.wesleyan.edu/">Wesleyan HFOSS team</a>, which went live
582)     in early 2011.
583)     </p>
584)     
585)     <a id="project-gettor"></a>
586)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/projects/EmailAutoResponder">GetTor</a> (<a

587)     href="https://gitweb.torproject.org/gettor.git">code</a>, <a

588)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=GetTor&order=priority">bug
589)     tracker</a>)</h3>
590)     
591)     <p>
592)     E-mail autoresponder providing Tor's packages over SMTP. This has been
593)     relatively unchanged for quite a while.
594)     </p>
595)     
596)     <a id="project-torcheck"></a>
597)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/projects/TorCheck">TorCheck</a> (<a
598)     href="https://svn.torproject.org/svn/check/trunk/">code</a>, <a
599)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Tor+Check&order=priority">bug
600)     tracker</a>)</h3>
601)     
602)     <p>
603)     Provides a simple site for determining if the visitor is using Tor or not.
604)     This has been relatively unchanged for quite a while.
605)     </p>
606)     
607)     <a id="project-bridgedb"></a>
608)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/projects/BridgeDB">BridgeDB</a> (<a
609)     href="https://gitweb.torproject.org/bridgedb.git">code</a>, <a
610)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=BridgeDB&order=priority">bug
611)     tracker</a>)</h3>
612)     
613)     <p>
614)     Backend bridge distributor, handling the various pools they're distributed
615)     in. This was actively developed until Fall of 2010.
616)     </p>
617)     
618)     <a id="project-torflow"></a>
619)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/projects/TorFlow">TorFlow</a> (<a
620)     href="https://gitweb.torproject.org/torflow.git">code</a>, <a
621)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torflow&order=priority">bug
622)     tracker</a>)</h3>
623)     
624)     <p>
625)     Library and collection of services for actively monitoring the Tor network.
626)     These include the Bandwidth Scanners (measuring throughput of relays) and
627)     SoaT (scans for malicious or misconfigured exit nodes). SoaT was last
628)     actively developed in the Summer of 2010, and the Bandwidth Scanners a few
629)     months later. Both have been under active use since then, but development
630)     has stopped.
631)     </p>
632)     
633)     <a id="project-torbel"></a>
634)     <h3><a
635)     href="https://trac.torproject.org/projects/tor/wiki/projects/TorBulkExitlist">TorBEL</a> (<a
636)     href="https://gitweb.torproject.org/tordnsel.git">code</a>, <a
637)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=TorDNSEL/TorBEL&order=priority">bug
638)     tracker</a>)</h3>
639)     
640)     <p>
641)     The Tor Bulk Exitlist provides a method of identifying if IPs belong to
642)     exit nodes or not. This is a replacement for TorDNSEL which is a stable
643)     (though unmaintained) Haskell application for this purpose. The initial
644)     version of TorBEL was started in GSOC 2010 but since then the project has
645)     been inactive.
646)     </p>
647)     

648)     <a id="Coding"></a>
649)     <a id="Summer"></a>

650)     <h2><a class="anchor" href="#Coding">Project Ideas</a></h2>

651)     
652)     <p>
653)     You may find some of these projects to be good <a href="<page

654)     about/gsoc>">Google Summer of Code 2011</a> ideas. We have labelled each idea

655)     with how useful it would be to the overall Tor project (priority), how
656)     much work we expect it would be (effort level), how much clue you should
657)     start with (skill level), and which of our <a href="<page

658)     about/corepeople>">core developers</a> would be good mentors.

659)     If one or more of these ideas looks promising to you, please <a
660)     href="<page about/contact>">contact us</a> to discuss your plans rather than
661)     sending blind applications. You may also want to propose your own project
662)     idea &mdash; which often results in the best applications.
663)     </p>
664)     
665)     <ol>
666)     

667)     <a id="auditTBB"></a>

668)     <li>

669)     <b>Audit Tor Browser Bundles for data leaks</b>

670)     <br>

671)     Priority: <i>High</i>

672)     <br>

673)     Effort Level: <i>High</i>

674)     <br>

675)     Skill Level: <i>Medium</i>

676)     <br>

677)     Likely Mentors: <i>Jacob</i>

678)     <p>The Tor Browser Bundle incorporates Tor, Firefox, Polipo, and the Vidalia

679)     user interface (and optionally the <a href="http://pidgin.im/">Pidgin</a>
680)     Instant Messaging client). Components are pre-configured to operate in a
681)     secure way, and it has very few dependencies on the installed operating
682)     system. It has therefore become one of the most easy to use, and popular,

683)     ways to use Tor on Windows.</p>
684)     <p>This project is to identify all of the traces left behind by
685)     using a Tor Browser Bundle on Windows, Mac OS X, or Linux.  Developing
686)     ways to stop, counter, or remove these traces is a final step.</p>
687)     <p>Students should be familiar with operating system analysis,

688)     application development on one or preferably all of Windows, Linux,

689)     and Mac OS X, and be comfortable with C/C++ and shell scripting.</p>

690)     </li>
691)     

692)     <a id="firewallProbeTool"></a>
693)     <li>
694)     <b>Develop a fully automatic firewall-probing system</b>
695)     <br>
696)     Priority: <i>High</i>
697)     <br>
698)     Effort Level: <i>Medium to High</i>
699)     <br>
700)     Skill Level: <i>High</i>
701)     <br>

702)     Likely Mentors: <i>Robert Ransom, Jacob</i>

703)     <p>We would like to have a fully automatic firewall-probing system for
704)     blocking systems with no long-term state (i.e. firewalls that can
705)     examine each connection, but do not change their behaviour for future
706)     connections based on the traffic they have seen).</p>
707)     <p>Ideally, volunteers would only need to set up one or more test servers,
708)     and run the probe client program on a publicly accessible computer
709)     behind the firewall.</p>
710)     <p>The test tool should:</p>
711)     <ul>
712)     <li>generate packet captures on both ends (and send them out to the
713)         extent possible),</li>
714)     <li>cycle through all the SSL configurations we might want to test
715)         through a censorship device, and</li>
716)     <li>also test some other protocols to see whether they are allowed
717)         through the firewall (IMAP and other mail protocols, BitTorrent,
718)         DTLS, etc.).</li>
719)     </ul>
720)     </li>
721)     

722)     <a id="orbot-torbutton"></a>
723)     <li>
724)     <b>TorButton for Mobile Firefox 4 or Custom Browser on Android</b>
725)     <br>
726)     Priority: <i>High</i>
727)     <br>
728)     Effort Level: <i>High</i>
729)     <br>
730)     Skill Level: <i>High</i>
731)     <br>

732)     Likely Mentors: <i>Jake</i>

733)     <p>Initial work has been done on implementing a proxy-setting add-on for
734)     Firefox on Android (see <a
735)     href="https://github.com/guardianproject/ProxyMob">ProxyMob</a>), but a
736)     full port of TorButton needs to be done (dependent upon Firefox 4 port of
737)     TorButton). The other approach is to implement a custom &quot;Tor
738)     Browser&quot; based on Firefox or Webkit browser. See <a
739)     href="http://code.google.com/p/torora/wiki/Android">Torora</a> for progress
740)     on this so far.</p>
741)     </li>
742)     

743)     <a id="obfsproxy-new-transports"></a>
744)     <li>
745)     <b>New and innovative pluggable transports</b>
746)     <br>
747)     Priority: <i>High</i>
748)     <br>
749)     Effort Level: <i>High</i>
750)     <br>
751)     Skill Level: <i>High</i>
752)     <br>
753)     Likely Mentors: <i>asn</i>
754)     <p>Not-very-smart transports like ROT13 and base64 are nice but not super
755)     interesting. Other ideas like bittorrent transports might be relevant,
756)     but you will have to provide security proofs on why they are harder to
757)     detect and block than other less-sophisticated transports.</p>
758)     
759)     <p>The whole point of this project, though, is to come up with new
760)     transports that we haven't already thought of. Be creative.</p>
761)     
762)     <p>Bonus points if your idea is interesting and still implementable
763)     through the summer period.</p>
764)     
765)     <p>More bonus points if it's implemented on top of obfsproxy, or if your
766)     implementation has a pluggable transport interface on top of it (as
767)     specified <a href="https://gitweb.torproject.org/torspec.git/blob/HEAD:/proposals/180-pluggable-transport.txt">here</a>).</p>
768)     </li>
769)     
770)     <a id="obfsproxy-scanning-measures"></a>
771)     <li>
772)     <b>Defensive bridge active scanning measures</b>
773)     <br>
774)     Priority: <i>High</i>
775)     <br>
776)     Effort Level: <i>High</i>
777)     <br>
778)     Skill Level: <i>High</i>
779)     <br>
780)     Likely Mentors: <i>asn</i>
781)     <p>Involves providing good answers to <a
782)     href="https://lists.torproject.org/pipermail/tor-dev/2011-November/003073.html">this
783)     thread</a> as well as concrete implementation plans for it.</p>
784)     
785)     <p>This also involves implementing proposals <a
786)     href="https://gitweb.torproject.org/torspec.git/blob/HEAD:/proposals/189-authorize-cell.txt">189</a>
787)     and <a
788)     href="https://gitweb.torproject.org/torspec.git/blob/HEAD:/proposals/190-shared-secret-bridge-authorization.txt">190</a>.</p>
789)     </li>
790)     

791)     <a id="stemPathsupport"></a>
792)     <li>
793)     <b>Stem PathSupport Capabilities</b>
794)     <br>
795)     Priority: <i>High</i>
796)     <br>
797)     Effort Level: <i>High</i>
798)     <br>
799)     Skill Level: <i>Medium</i>
800)     <br>
801)     Likely Mentors: <i>Damian (atagar)</i>
802)     <p><a
803)     href="https://trac.torproject.org/projects/tor/wiki/doc/stem">Stem</a> is a
804)     python controller library for tor. Like it's predecessor, <a
805)     href="#project-torctl">TorCtl</a>, it uses tor's <a
806)     href="https://gitweb.torproject.org/torspec.git/blob/HEAD:/control-spec.txt">control
807)     protocol</a> to help developers program against the tor process, enabling
808)     them to build things similar to <a href="#project-vidalia">Vidalia</a> and
809)     <a href="#project-arm">arm</a>.</p>
810)     
811)     <p>While TorCtl provided a fine first draft for this sort of functionality,
812)     it has not proved to be extensible nor maintainable. Stem is a rewrite of
813)     TorCtl with a heavy focus on testing, documentation, and providing a
814)     developer friendly API.</p>
815)     
816)     <p>At the moment stem is still very much incomplete, missing several pieces
817)     of functionality that TorCtl provides. This is a project to fix that by
818)     porting TorCtl's <a
819)     href="https://gitweb.torproject.org/pytorctl.git/blob/HEAD:/PathSupport.py">PathSupport
820)     module</a> to stem, writing tests for it, and migrate a couple clients to
821)     use it.</p>
822)     
823)     <p>PathSupport provides applications with programmatic control over how
824)     tor's circuits are built, for instance letting you exit from particular
825)     relays. This is used by projects like <a href="#project-torbel">TorBEL</a>,
826)     <a href="#project-torflow">the Bandwidth Scanners, and SoaT</a>.</p>
827)     
828)     <p>This project can be broken into three parts...</p>
829)     
830)     <ol style="list-style-type: decimal">
831)       <li><p>Look at PathSupport's clients to figure out how it is used and
832)       come up with the API that we will use for stem. Note that the goal if
833)       this project is <b>not</b> to simply copy PathSupport, but to make it
834)       better. This task would ideally be done as part of writing the GSoC
835)       application.</p></li>
836)       <li><p>Implement the PathSupport counterpart for stem. This should be
837)       done in an incremental fashion, writing the feature, tests, and going
838)       through a code review before moving on. I'll be pretty anal about making
839)       it as good as we can during these code reviews so plan for this to take a
840)       while. ;)</p></li>
841)       <li><p>The real test of the API that you've developed will come when we
842)       use it in some real applications. Try to migrate a TorCtl client or two
843)       to stem, filling in functionality that we're missing and improving our
844)       API as we discover issues. A particularly good client to start with would
845)       be TorBEL.</p></li>
846)     </ol>
847)     

848)     <a id="orbot-userInterface"></a>
849)     <li>
850)     <b>Build a better user interface for Orbot</b>
851)     <br>
852)     Priority: <i>High</i>
853)     <br>
854)     Effort Level: <i>Medium</i>
855)     <br>
856)     Skill Level: <i>Medium</i>
857)     <br>

858)     Likely Mentors: <i>Jake</i>

859)     <p>Improved home screen to show confirmation of connection (via a TorCheck
860)     API call), better statistics about data transferred (up/down), number of
861)     circuits connected, quality of connection and so on. The &quot;Tether
862)     Wifi&quot; Android application is a good model to follow in how it shows a
863)     realtime count of bytes transferred as well as notifications when wifi
864)     clients connect. In addition, better handling of Tor system and error
865)     messages would also be very helpful, include use of standard Android
866)     operating systems notifications. The addition of a wizard or tutorial
867)     walkthrough for novice users to explain to them exactly what is and what is
868)     not anonymized or protected would greatly improve the likelihood they will
869)     use Orbot correctly. All of this should work on the range of screens and
870)     device types now offered for Android, from 2&quot; phone to 10&quot;
871)     Tablet.</p>
872)     </li>
873)     

874)     <a id="resistCensorship"></a>

875)     <li>
876)     <b>Improving Tor's ability to resist censorship</b>

877)     <br>

878)     Priority: <i>Medium to High</i>

879)     <br>

880)     Effort Level: <i>Medium to High</i>

881)     <br>

882)     Skill Level: <i>High</i>

883)     <br>

884)     Likely Mentors: <i>Jake, Thomas</i>

885)     <p>The Tor 0.2.1.x series makes <a

886)     href="<svnprojects>design-paper/blocking.html">significant
887)     improvements</a> in resisting national and organizational censorship.
888)     But Tor still needs better mechanisms for some parts of its

889)     anti-censorship design.</p>
890)     <p>One huge category of work is adding features to our <a

891)     href="https://gitweb.torproject.org/bridgedb.git?a=tree">BridgeDB</a>

892)     service (Python). Tor aims to give out <a href="<page docs/bridges>">bridge
893)     relay addresses</a> to users that can't reach the Tor network
894)     directly, but there's an arms race between algorithms for distributing
895)     addresses and algorithms for gathering and blocking them. See <a

896)     href="<blog>bridge-distribution-strategies">our

897)     blog post on the topic</a> as an overview, and then look at <a

898)     href="https://lists.torproject.org/pipermail/tor-dev/2009-December/000666.html">Roger's
899)     or-dev post</a> from December 2009 for more recent thoughts &mdash; lots of

900)     design work remains.</p>
901)     <p>If you want to get more into the guts of Tor itself (C), a more minor problem

902)     we should address is that current Tors can only listen on a single
903)     address/port combination at a time. There's

904)     <a href="<specblob>proposals/118-multiple-orports.txt">a

905)     proposal to address this limitation</a> and allow clients to connect
906)     to any given Tor on multiple addresses and ports, but it needs more

907)     work.</p>
908)     <p>This project could involve a lot of research and design. One of the big

909)     challenges will be identifying and crafting approaches that can still
910)     resist an adversary even after the adversary knows the design, and

911)     then trading off censorship resistance with usability and
912)     robustness.</p>

913)     </li>
914)     

915)     <a id="tailsHiddenServicePetnames"></a>
916)     <li>
917)     <b>Petname system for Tor hidden services</b>
918)     <br>
919)     Priority: <i>Medium</i>
920)     <br>
921)     Effort Level: <i>High</i>
922)     <br>
923)     Skill Level: <i>High</i>
924)     <br>
925)     Likely Mentors: <i>ague</i>
926)     <p>Tor provides hidden services. These services are only reachable through
927)     Tor itself, and provide greater anonymity both for the providers of the
928)     service and for its users.</p>
929)     <p>One current downside of Tor hidden services is that they are addressed
930)     using 80-bit base32-encoded addresses such as "v2cbb2l4lsnpio4q.onion".
931)     These addresses are hard to remember; this makes them hard to use
932)     within amnesic environment like Tails.</p>
933)     <p>The project is to implement a petname system for Tor hidden services:
934)     a way for users or providers of Tor hidden services to add a simple
935)     'nickname' to a central database. Users could then query this central
936)     database to retrieve a full hidden service address by giving
937)     a nickname.</p>
938)     <p>Adding petnames to the database could be done using a web interface or
939)     automated fetch like those described in the <a
940)     href="https://gitweb.torproject.org/torspec.git/blob/HEAD:/proposals/ideas/xxx-onion-nyms.txt">&quot;.onion
941)     nym system&quot; proposal</a>.</p>
942)     <p>Querying the database could be done using a web interface, a REST API and
943)     a DNS interface.</p>
944)     <p>In order not to grow indefinitely, the software should make regular tests to
945)     see if hidden services are still reachable and, depending on the last time
946)     a nickname was accessed, cleanup the database as necessary.</p>
947)     <p>The software should allow a distributed, fault-tolerant setup.
948)     All nodes should have a synchronized copy of the database, should be
949)     ready to answer queries and should coordinate the tests for hidden
950)     service availability.</p>
951)     <p>The resulting codebase must be easy to deploy: it should not be hard to
952)     setup new databases.</p>
953)     <p>It is expected that the volunteer will be using Behaviour Driven
954)     Development methods. Either in Ruby using Cucumber and RSpec, or in
955)     Python using similar tools.</p>
956)     </li>
957)     
958)     <a id="tailsServer"></a>
959)     <li>
960)     <b>Tails server: Self-hosted services behind Tails-powered Tor hidden services</b>
961)     <br>
962)     Priority: <i>Medium</i>
963)     <br>
964)     Effort Level: <i>High</i>
965)     <br>
966)     Skill Level: <i>Medium, but wide-scoped</i>
967)     <br>
968)     Likely Mentors: <i>intrigeri, anonym</i>
969)     <p>Let's talk about group collaboration, communication and data sharing
970)     infrastructure, such as chat servers, wikis, or file repositories.</p>
971)     <p>Hosting such data and infrastructure <b>in the cloud</b> generally
972)     implies to trust the service providers not to disclose content, usage or
973)     users location information to third-parties. Hence, there are many threat
974)     models in which cloud hosting is not suitable.</p>
975)     <p>Tor partly answers the <b>users location</b> part; this is great, but
976)     <b>content</b> is left unprotected.</p>
977)     <p>There are two main ways to protect such content: either to encrypt it
978)     client-side (<b>security by design</b>), or to avoid putting it into
979)     untrusted hands in the first place.</p>
980)     <p>Cloud solutions that offer security by design are rare and generally
981)     not mature yet. The <b>Tails server</b> project is about exploring the
982)     other side of the alternative: avoiding to put private data into
983)     untrusted hands in the first place.</p>
984)     <p>This is made possible thanks to Tor hidden services, that allow users
985)     to offer location-hidden services, and make self-hosting possible in
986)     many threat models. Self-hosting has its own lot of problems, however,
987)     particularly in contexts where the physical security of the hosting
988)     place is not assured. Combining Tor hidden services with Tails'
989)     amnesia property and limited support for persistent encrypted data
990)     allows to protect content, to a great degree, even in such contexts.</p>
991)     <p>In short, setting up a new Tails server would be done by:</p>
992)     
993)     <ol style="list-style-type: decimal">
994)       <li>Alice plugs a USB stick into a running desktop Tails system.</li>
995)       <li>Alice uses a GUI to easily configure the needed services.</li>
996)       <li>Alice unplugs the USB stick, that now contains encrypted services
997)       configuration and data storage space.</li>
998)       <li>Alice plugs that USB stick (and possibly a Tails Live CD) into the
999)       old laptop that was dedicated to run Tails server.</li>
1000)       <li>Once booted, Alice enters the encryption passphrase either
1001)       directly using the keyboard or through a web interface listening on the
1002)       local network.</li>
1003)       <li>Then, Bob can use the configured services once he gets a hold on
1004)       the hidden service address. (The <b>petname system for Tor hidden
1005)       services</b> project would be very complementary to this one, by the
1006)       way.)</li>
1007)     </ol>
1008)     
1009)     <p>Tails server should content itself with hardware that is a bit old
1010)     (such as a PIII-450 laptop with 256MB of RAM) and/or half broken (e.g.
1011)     non-functional hard-disk, screen or keyboard).</p>
1012)     <p>The challenges behind this project are:</p>
1013)     
1014)     <ul>
1015)       <li>Design and write the services configuration GUI [keywords: edit
1016)       configuration files, upgrade between major Debian versions,
1017)       debconf].</li>
1018)       <li>How to create the hidden service key? [keywords: Vidalia, control
1019)       protocol].</li>
1020)       <li>Adapt the Tails boot process to allow switching to &quot;server
1021)       mode&quot; when appropriate.</li>
1022)       <li>Add support, to the Tails persistence setup process, for asking an
1023)       encryption passphrase without X, and possibly with a broken keyboard
1024)       and/or screen [keywords: local network, SSL/TLS?, certificate?].</li>
1025)     </ul>
1026)     
1027)     <p>This project can easily grow quite large, so the first task would
1028)     probably be to clarify what it would need to get an initial (minimal
1029)     but working) implementation ready to be shipped to users.</p>
1030)     <p>This project does not require to be an expert in one specific field,
1031)     but it requires to be experienced and at ease with a large scope of
1032)     software development tools, processes, and operating system knowledge.</p>
1033)     <p>Undertaking this project requires in-depth knowledge of Debian-like
1034)     systems (self-test: do the "dpkg conffile" and "debconf preseeding"
1035)     words sound new to your ear?); the Debian Live persistence system
1036)     being written in shell, being at ease with robust shell scripting is
1037)     a must; to end with, at least two pieces of software need to be
1038)     written from scratch (a GUI and a webapp): the preferred languages for
1039)     these tasks would be Python and Perl. Using Behaviour Driven
1040)     Development methods to convey expectations and acceptance criteria
1041)     would be most welcome.</p>
1042)     <p>For more information see https://tails.boum.org/todo/server_edition/</p>
1043)     </li>
1044)     

1045)     <a id="geoIPUpgrade"></a>
1046)     <li>
1047)     <b>Improve our GeoIP file format</b>
1048)     <br>
1049)     Priority: <i>Medium</i>
1050)     <br>
1051)     Effort Level: <i>Medium</i>
1052)     <br>
1053)     Skill Level: <i>Medium to High</i>
1054)     <br>
1055)     Likely Mentors: <i>Robert Ransom</i>

1056)     <p>Currently, Tor bridges and relays read an entire IP-&gt;country database

1057)     into memory from a text file during startup.  We would like to
1058)     distribute this database and store it on disk in a much more compact

1059)     form, and perform IP->country lookups on it in its on-disk format if

1060)     possible.</p>

1061)     <p>We have <a href='https://trac.torproject.org/projects/tor/ticket/2506'>a
1062)     sketch of a design</a> for a moderately optimized format for IPv4 GeoIP
1063)     data; this project will involve both implementing the IPv4 format and
1064)     designing and implementing a format for IPv6 GeoIP data.</p>

1065)     <p>Since the core of this project is researching IPv6 GeoIP data and

1066)     designing the IPv6 format, this is not likely to be a good GSoC

1067)     project.</p>

1068)     </li>
1069)     

1070)     <!--

1071)     <a id="armClientMode"></a>

1072)     <li>
1073)     <b>Client Mode Use Cases for Arm</b>
1074)     <br>
1075)     Priority: <i>Medium</i>
1076)     <br>
1077)     Effort Level: <i>High</i>
1078)     <br>
1079)     Skill Level: <i>Medium</i>
1080)     <br>

1081)     Likely Mentors: <i>Damian (atagar)</i>

1082)     <p><a href="<page projects/arm>">Arm</a> is a Tor command line status
1083)     monitor on *nix environments (Linux, Mac, and BSD). It functions much like
1084)     top does, giving a CLI overlay of Tor's bandwidth usage, connections,
1085)     configuration, log, etc. Thus far its design has been geared for Tor relay
1086)     operators. However, this doesn't need to be the case. This project would be
1087)     to expand and simplify arm to make it useful for Tor's client users
1088)     too.</p>
1089)     
1090)     <p>This would include UI design, experimenting, and a lot of python
1091)     hacking. Here's some ideas for client functionality arm could provide:</p>
1092)     
1093)     <ul>
1094)       <li>A panel for client connections, showing each hop of the user's
1095)       circuits with the ISP, country, and jurisdiction where those relays
1096)       reside. Other interesting information would be the circuit's latency, how
1097)       long its been around, and its possible exit ports. Some of this will be
1098)       pretty tricky and require some experimentation to figure out what
1099)       information can be fetched safely (for instance, scraping rdns and whois
1100)       lookups could give hints about a relay's ISP, but we'd need to do it on
1101)       all Tor relays to avoid leaking our connections to the resolver).</li>
1102)       
1103)       <li>Options to let the user request new circuits (the &quot;New
1104)       Identity&quot; feature in Vidalia), select the exit country, etc.</li>
1105)       
1106)       <li>A panel showing Internet application and if their connections are
1107)       being routed through Tor or not (giving a warning if there's leaks).</li>
1108)       
1109)       <li>The status of the bridges we're configured to use (ie, are they up?).
1110)       This would include adding control port functionality to Tor for <a
1111)       href="https://trac.torproject.org/projects/tor/ticket/2068">ticket
1112)       2068</a>.</li>
1113)       
1114)       <li>A one click option to set Tor to be a client, relay, or bridge. The
1115)       goal would be to make it trivial for users to voluntarily contribute to
1116)       the Tor network.</li>
1117)       
1118)       <li>Menus as an alternative to hotkeys to make the interface more
1119)       intuitive and usable for beginners (<a
1120)       href="http://gnosis.cx/publish/programming/charming_python_6.html">example</a>).</li>
1121)       
1122)       <li>Look at Vidalia and TorK for ideas and solicit input from the Tor community.</li>
1123)     </ul>
1124)     

1125)     <p>
1126)     More information is available in the following sections of arm's dev notes: <a href="https://trac.torproject.org/projects/tor/wiki/projects/arm#ConnectionListingExpansion">Connection Listing Expansion</a>, <a href="https://trac.torproject.org/projects/tor/wiki/projects/arm#CircuitDetails">Circuit Details</a>, and <a href="https://trac.torproject.org/projects/tor/wiki/projects/arm#ClientModeUseCases">Client Mode Use Cases</a>
1127)     </p>

1128)     </li>

1129)     -->

1130)     

1131)     <a id="vidalia-hidden-service-panel"></a>
1132)     <li>
1133)     <b>Torrc plugin and improved hidden service configuration panel</b>
1134)     <br>
1135)     Priority: <i>Medium</i>
1136)     <br>
1137)     Effort Level: <i>Medium</i>
1138)     <br>
1139)     Skill Level: <i>Medium</i>
1140)     <br>
1141)     Likely Mentors: <i>Tomás</i>
1142)     <p>Vidalia's configuration handling has changed in the alpha branch. Now
1143)     every Tor option is saved in the torrc file. With that change, the
1144)     Hidden Service configuration panel was removed due to its specificity
1145)     and its multiple bugs.</p>
1146)     
1147)     <p>The idea would be to provide the new Torrc class' functionality to the
1148)     Plugin Engine and with that, create a better Hidden Service
1149)     configuration panel as a plugin.</p>
1150)     
1151)     <p>A person undertaking this project should have good UI design, layout
1152)     skills and some C++ development experience. Previous experience with Qt
1153)     and Qt's Designer will be very helpful, but are not required. Javascript
1154)     knowledge is a plus, but it shouldn't be a problem if the person
1155)     complies with the previous requirements.</p>
1156)     </li>
1157)     

1158)     <a id="metricsSearch"></a>
1159)     <li>
1160)     <b>Searchable Tor descriptor and Metrics data archive</b>
1161)     <br>
1162)     Priority: <i>Medium</i>
1163)     <br>
1164)     Effort Level: <i>Medium</i>
1165)     <br>
1166)     Skill Level: <i>Medium</i>
1167)     <br>
1168)     Likely Mentors: <i>Karsten</i>
1169)     <p>The <a href="https://metrics.torproject.org/data.html">Metrics data archive</a> of Tor relay descriptors and other Tor-related network data has grown to over 100G in size, bz2-compressed.  We have developed two search interfaces: the <a href="https://metrics.torproject.org/relay-search.html">relay search</a> finds relays by nickname, fingerprint, or IP address in a given month; <a href="https://metrics.torproject.org/exonerator-beta.html">ExoneraTor</a> finds whether a given IP address was a relay on a given day.</p>
1170)     
1171)     <p>We'd like to have a more general search application for Tor descriptors and metrics data.  There are more <a href="https://metrics.torproject.org/formats.html">descriptor types</a> that we'd like to include in the search.  The search application should handle most of them and understand some semantics like what's a timestamp, what's an IP address, and what's a link to another descriptor.  Users should then be able to search for arbitrary strings or limit their search to given time periods or IP address ranges.  Descriptors that reference other descriptors should contain links, and descriptors should be able to say from where they are linked.  The goal is to make the archive easily browsable.</p>
1172)     
1173)     <p>The search application shall be separate from the metrics website and shouldn't rely on the metrics website codebase.  The search application will contain hourly updated descriptor data from the metrics website via rsync.  Programming language and database system are not specified yet, though there's a slight preference for Python/Django and Postgres for maintenance reasons.  If there are good reasons to pick something else, e.g, some NoSQL variant or some search application framework, that's fine, too.  Further requirements are that lookups should be really fast and that changes to the search application can be implemented in reasonable time.</p>
1174)     
1175)     <p>Applications for this project should come with a design of the proposed search application, ideally with a proof-of-concept based on a subset of the available data to show that it will be able to handle the 100G+ of data.</p>
1176)     

1177)     <!--

1178)     <a id="unitTesting"></a>

1179)     <li>
1180)     <b>Improve our unit testing process</b>

1181)     <br>

1182)     Priority: <i>Medium</i>

1183)     <br>

1184)     Effort Level: <i>Medium</i>

1185)     <br>

1186)     Skill Level: <i>Medium</i>

1187)     <br>

1188)     Likely Mentors: <i>Nick, Erinn</i>

1189)     <p>Tor needs to be tested far more thoroughly. This is a
1190)     multi-part effort. To start with, our unit test coverage should
1191)     rise substantially, especially in the areas outside the utility
1192)     functions. This will require significant refactoring of some parts
1193)     of Tor, in order to dissociate as much logic as possible from
1194)     globals.</p>

1195)     <p>Additionally, we need to automate our performance testing. We've got

1196)     buildbot to automate our regular integration and compile testing already
1197)     (though we need somebody to set it up on Windows),
1198)     but we need to get our network simulation tests (as built in <a
1199)     href="https://svn.torproject.org/svn/torflow/trunk/README">TorFlow</a>)
1200)     updated for more recent versions of Tor, and designed to launch a test
1201)     network either on a single machine, or across several, so we can test

1202)     changes in performance on machines in different roles automatically.</p>

1203)     </li>

1204)     -->

1205)     

1206)     <!--

1207)     <a id="simulateSlowConnections"></a>

1208)     <li>
1209)     <b>Simulator for slow Internet connections</b>

1210)     <br>

1211)     Priority: <i>Medium</i>

1212)     <br>

1213)     Effort Level: <i>Medium</i>

1214)     <br>

1215)     Skill Level: <i>Medium</i>

1216)     <br>

1217)     Likely Mentors: <i>Nick</i>

1218)     <p>

1219)     Many users of Tor have poor-quality Internet connections, giving low
1220)     bandwidth, high latency, and high packet loss/re-ordering. User
1221)     experience is that Tor reacts badly to these conditions, but it is
1222)     difficult to improve the situation without being able to repeat the
1223)     problems in the lab.

1224)     </p>
1225)     
1226)     <p>

1227)     This project would be to build a simulation environment which
1228)     replicates the poor connectivity so that the effect on Tor performance
1229)     can be measured. Other components would be a testing utility to
1230)     establish what are the properties of connections available, and to
1231)     measure the effect of performance-improving modifications to Tor.

1232)     </p>
1233)     
1234)     <p>

1235)     The tools used would be up to the student, but dummynet (for FreeBSD)
1236)     and nistnet (for Linux) are two potential components on which this
1237)     project could be built. Students should be experienced with network
1238)     programming/debugging and TCP/IP, and preferably familiar with C and a
1239)     scripting language.

1240)     </p>

1241)     </li>

1242)     -->

1243)     

1244)     <a id="torbuttonForThunderbird"></a>

1245)     <li>
1246)     <b>Torbutton equivalent for Thunderbird</b>

1247)     <br>

1248)     Priority: <i>Medium</i>

1249)     <br>

1250)     Effort Level: <i>High</i>

1251)     <br>

1252)     Skill Level: <i>High</i>

1253)     <br>

1254)     Likely Mentors: <i>Mike</i>

1255)     <p>

1256)     We're hearing from an increasing number of users that they want to use
1257)     Thunderbird with Tor. However, there are plenty of application-level
1258)     concerns, for example, by default Thunderbird will put your hostname in
1259)     the outgoing mail that it sends. At some point we should start a new
1260)     push to build a Thunderbird extension similar to Torbutton.

1261)     </p>

1262)     </li>
1263)     

1264)     <a id="usabilityTesting"></a>

1265)     <li>
1266)     <b>Usability testing of Tor</b>

1267)     <br>

1268)     Priority: <i>Medium</i>

1269)     <br>

1270)     Effort Level: <i>Medium</i>

1271)     <br>

1272)     Skill Level: <i>Low to Medium</i>

1273)     <br>

1274)     Likely Mentors: <i>Andrew</i>

1275)     <p>

1276)     Especially the browser bundle, ideally amongst our target demographic.
1277)     That would help a lot in knowing what needs to be done in terms of bug
1278)     fixes or new features. We get this informally at the moment, but a more
1279)     structured process would be better.

1280)     </p>

1281)     
1282)     <p>
1283)     Please note that since this isn't a coding project, it isn't suitable for
1284)     Google Summer of Code.
1285)     </p>

1286)     </li>

1287)     

1288)     <!--

1289)     <a id="torsocksForOSX"></a>

1290)     <li>
1291)     <b>Make torsocks/dsocks work on OS X</b>

1292)     <br>

1293)     Priority: <i>Medium</i>

1294)     <br>

1295)     Effort Level: <i>Medium</i>

1296)     <br>

1297)     Skill Level: <i>Medium</i>

1298)     <br>

1299)     Likely Mentors: <i>Robert Hogan</i>

1300)     <p>

1301)     <a href="https://code.google.com/p/torsocks/">Torsocks</a> and <a
1302)     href="https://code.google.com/p/dsocks/">dsocks</a> are wrappers that will

1303)     run applications, intercept their outgoing network connections, and push
1304)     those connections through Tor. The goal is to handle applications that
1305)     don't support proxies (or don't supporting them well). To get it right,
1306)     they need to intercept many system calls. The syscalls you need to
1307)     intercept on Linux differ dramatically from those on BSD. So Torsocks
1308)     works fine on Linux, dsocks works ok on BSD (though it may be less
1309)     maintained and thus might miss more syscalls), and nothing works well
1310)     on both. First, we should patch dsocks to use Tor's <i>mapaddress</i>
1311)     commands from the controller interface, so we don't waste a whole
1312)     round-trip inside Tor doing the resolve before connecting. Second,
1313)     we should make our <i>torify</i> script detect which of torsocks or
1314)     dsocks is installed, and call them appropriately. This probably means
1315)     unifying their interfaces, and might involve sharing code between them
1316)     or discarding one entirely.

1317)     </p>
1318)     </li>

1319)     -->

1320)     

1321)     <a id="vidaliaStatusEventInterface"></a>

1322)     <li>
1323)     <b>Tor Controller Status Event Interface for Vidalia</b>
1324)     <br>
1325)     Priority: <i>Medium</i>
1326)     <br>
1327)     Effort Level: <i>Medium</i>
1328)     <br>
1329)     Skill Level: <i>Low to Medium</i>
1330)     <br>

1331)     Likely Mentors: <i>Tomás</i>

1332)     <p>There are a number of status changes inside Tor of which the user may need
1333)     to be informed. For example, if the user is trying to set up his Tor as a
1334)     relay and Tor decides that its ports are not reachable from outside
1335)     the user's network, we should alert the user. Currently, all the user
1336)     gets is a couple of log messages in Vidalia's 'message log' window, which they
1337)     likely never see since they don't receive a notification that something
1338)     has gone wrong. Even if the user does actually look at the message log,
1339)     most of the messages make little sense to the novice user.</p>
1340)     <p>Tor has the ability to inform Vidalia of many such status
1341)     changes, and we recently implemented support for a couple of these
1342)     events. Still, there are many more status events which the user should
1343)     be informed of, and we need a better UI for actually displaying them
1344)     to the user.</p>
1345)     <p>The goal of this project then is to design and implement a UI for
1346)     displaying Tor status events to the user. For example, we might put a
1347)     little badge on Vidalia's tray icon that alerts the user to new status
1348)     events they should look at. Double-clicking the icon could bring up a
1349)     dialog that summarizes recent status events in simple terms and maybe
1350)     suggests a remedy for any negative events if they can be corrected by
1351)     the user. Of course, this is just an example and one is free to
1352)     suggest another approach.</p>
1353)     <p>A person undertaking this project should have good UI design and layout
1354)     skills and some C++ development experience. Previous experience with Qt and
1355)     Qt's Designer will be very helpful, but are not required. Some
1356)     English writing ability will also be useful, since this project will
1357)     likely involve writing small amounts of help documentation that should
1358)     be understandable by non-technical users. Bonus points for some graphic
1359)     design/Photoshop fu, since we might want/need some shiny new icons too.</p>
1360)     </li>
1361)     

1362)     <a id="orbot-optimisation"></a>
1363)     <li>
1364)     <b>Core Tor mobile optimisation</b>
1365)     <br>
1366)     Priority: <i>Medium</i>
1367)     <br>
1368)     Effort Level: <i>Medium</i>
1369)     <br>
1370)     Skill Level: <i>High</i>
1371)     <br>

1372)     Likely Mentors: <i>Jake</i>

1373)     <p>
1374)     The existing port of Tor to Android is basically a straight
1375)     cross-compile to Linux ARM. There has been no work done in looking at
1376)     possible optimizations of Tor within a mobile hardware environment or on
1377)     mobile networks. In addition, a number of additional Android OS APIs are
1378)     available (such as wireless network status) that could be taken
1379)     advantage of.
1380)     </p>
1381)     
1382)     <p>
1383)     It should be noted, that even without optimisation, Tor is handling the
1384)     mobile network environment very well, automatically detecting change in
1385)     IP addresses, opening circuits, etc, as the device switches from no
1386)     coverage to 2G, 3G or Wifi constantly as it changes position. However,
1387)     this observation of &quot;very well&quot;, is just based on user
1388)     experience, and not any detailed study of what exactly is happening, and
1389)     what threats might exist because of this constantly changing network state.
1390)     </p>
1391)     
1392)     <p>
1393)     Finally, the build process needs to be moved to the Android NDK from the
1394)     custom GCC toolchain we are now using, and compatibility with Android
1395)     2.3 and 3.x Honeycomb OS need to be verified.
1396)     </p>
1397)     
1398)     <p>
1399)     For more information see the <a
1400)     href="https://svn.torproject.org/svn/projects/android/trunk/Orbot/BUILD">Orbot
1401)     build documentation</a>.
1402)     </p>
1403)     </li>
1404)     

1405)     <!--

1406)     <a id="orbot-orlibAndOutreach"></a>
1407)     <li>
1408)     <b>Orbot integration library and community outreach</b>
1409)     <br>
1410)     Priority: <i>Medium</i>
1411)     <br>
1412)     Effort Level: <i>Low</i>
1413)     <br>
1414)     Skill Level: <i>Medium</i>
1415)     <br>
1416)     Likely Mentors: <i>Nathan (n8fr8)</i>
1417)     <p>
1418)     We need additional work on <a
1419)     href="https://github.com/guardianproject/orlib">ORLib</a>, our library for
1420)     use with third-party application to easily enable them to support
1421)     &quot;Torification&quot; on non-rooted devices (i.e. w/o transparent
1422)     proxying). This library includes a SOCKS client, a wrapper for the Apache
1423)     HTTPClient library, a utility class for detecting the state of Orbot
1424)     connectivity, and other relevant/useful things an Android app might need to
1425)     anonymize itself. This work would includes direct development of the
1426)     library, documentation, and sample code. Outreach or effort to implement
1427)     the library within other open-source apps is also needed.
1428)     </p>
1429)     </li>

1430)     -->

1431)     

1432)     <!--

1433)     <a id="vidaliaNetworkMap"></a>

1434)     <li>
1435)     <b>An Improved and More Usable Network Map in Vidalia</b>
1436)     <br>
1437)     Priority: <i>Low to Medium</i>
1438)     <br>
1439)     Effort Level: <i>Medium</i>
1440)     <br>
1441)     Skill Level: <i>Medium</i>
1442)     <br>

1443)     Likely Mentors: <i>Tomás</i>

1444)     <p>
1445)     One of Vidalia's existing features is a network map that shows the user
1446)     the approximate geographic location of relays in the Tor network and
1447)     plots the paths the user's traffic takes as it is tunneled through the
1448)     Tor network. The map is currently not very interactive and has rather
1449)     poor graphics. Instead, we implemented KDE's Marble widget such
1450)     that it gives us a better quality map and enables improved interactivity,
1451)     such as allowing the user to click on individual relays or circuits to
1452)     display additional information. We want to add the ability
1453)     for users to click on a particular relay or a country containing one or
1454)     more Tor exit relays and say, "I want my connections to exit
1455)     from here."
1456)     </p>
1457)     
1458)     <p>
1459)     This project will first involve getting familiar with Vidalia
1460)     and the Marble widget's API. One will then integrate the widget
1461)     into Vidalia and customize Marble to be better suited for our application,
1462)     such as making circuits clickable, storing cached map data in Vidalia's
1463)     own data directory, and customizing some of the widget's dialogs.
1464)     </p>
1465)     
1466)     <p>
1467)     A person undertaking this project should have good C++ development
1468)     experience. Previous experience with Qt and CMake is helpful, but not
1469)     required.
1470)     </p>

1471)     </li>

1472)     -->

1473)     

1474)     <a id="obfsproxy-fuzzer"></a>
1475)     <li>
1476)     <b>Fuzzer for the Tor protocol</b>
1477)     <br>
1478)     Priority: <i>Low to Medium</i>
1479)     <br>
1480)     Effort Level: <i>Medium to High</i>
1481)     <br>
1482)     Skill Level: <i>High</i>
1483)     <br>
1484)     Likely Mentors: <i>asn</i>
1485)     <p>Involves researching good and smart ways to fuzz stateful network
1486)     protocols, and also implementing the fuzzer.</p>
1487)     
1488)     <p>We are mostly looking for a fuzzer that fuzzes the Tor protocol
1489)     itself, and not the Tor directory protocol.</p>
1490)     
1491)     <p>Bonus points if it's extremely modular. Relevant research:</p>
1492)     
1493)     <ul>
1494)       <li>PROTOS - Security Testing of Protocol Implementations</li>
1495)       <li>INTERSTATE: A Stateful Protocol Fuzzer for SIP</li>
1496)       <li>Detecting Communication Protocol Security Flaws by Formal Fuzz
1497)       Testing and Machine Learning</li>
1498)       <li>SNOOZE: Toward a Stateful NetwOrk prOtocol fuzZE</li>
1499)       <li>Michal Zalewski's &quot;bugger&quot;</li>
1500)       <li>Also look at the concepts of &quot;model checking&quot; and
1501)       &quot;symbolic execution&quot; to get inspired.</li>
1502)     </ul>
1503)     </li>
1504)     

1505)     <!--

1506)     <a id="armGui"></a>
1507)     <li>
1508)     <b>GUI for Arm</b>
1509)     <br>
1510)     Priority: <i>Low</i>
1511)     <br>
1512)     Effort Level: <i>High</i>
1513)     <br>
1514)     Skill Level: <i>Medium</i>
1515)     <br>

1516)     Likely Mentors: <i>Damian (atagar)</i>

1517)     <p>
1518)     Arm has several unique features, some of the most interesting being its
1519)     connection listing (correlating netstat results against the Tor consensus)
1520)     and configuration editor (a quick method for editing Tor's config, with
1521)     information pulled from the control port and man page). However, since arm
1522)     is a command line controller it's of limited appeal to certain sets of
1523)     users. This project would be to build a GTK or Qt frontend for the
1524)     controller, providing similar features set but with a windowed interface.
1525)     </p>
1526)     
1527)     <p>
1528)     The vast majority of arm's more interesting functionality lies in its

1529)     backend <a href="https://gitweb.torproject.org/arm.git/tree/HEAD:/src/util">utilities</a>, so

1530)     there should be little to no work decoupling the CLI from its backend.
1531)     Instead, this project would mostly be UI hacking and experimentation,
1532)     trying different interfaces to find something that's elegant and simple,
1533)     but matches the information found in the current terminal application.
1534)     </p>
1535)     </li>

1536)     -->

1537)     

1538)     <li>
1539)     <b>Bring up new ideas!</b>

1540)     <br>

1541)     Don't like any of these? Look at the <a

1542)     href="/press/presskit/2008-12-19-roadmap-full.pdf">Tor development

1543)     roadmap</a> for more ideas, or just try out Tor, Vidalia, and Torbutton,
1544)     and find out what you think needs fixing.

1545)     Some of the <a href="<spectree>proposals">current proposals</a>

1546)     might also be short on developers.
1547)     </li>
1548)     
1549)     </ol>
1550)     
1551)     <a id="OtherCoding"></a>
1552)     <h2><a class="anchor" href="#OtherCoding">Other Coding and Design related ideas</a></h2>
1553)     <ol>
1554)     <li>Tor relays don't work well on Windows XP. On
1555)     Windows, Tor uses the standard <tt>select()</tt> system
1556)     call, which uses space in the non-page pool. This means
1557)     that a medium sized Tor relay will empty the non-page pool, <a

1558)     href="<wiki>doc/WindowsBufferProblems">causing

1559)     havoc and system crashes</a>. We should probably be using overlapped IO
1560)     instead. One solution would be to teach <a
1561)     href="http://www.monkey.org/~provos/libevent/">libevent</a> how to use
1562)     overlapped IO rather than select() on Windows, and then adapt Tor to
1563)     the new libevent interface. Christian King made a
1564)     <a href="https://svn.torproject.org/svn/libevent-urz/trunk/">good
1565)     start</a> on this in the summer of 2007.</li>
1566)     
1567)     <li>We need to actually start building our <a href="<page
1568)     docs/documentation>#DesignDoc">blocking-resistance design</a>. This involves
1569)     fleshing out the design, modifying many different pieces of Tor, adapting
1570)     <a href="<page projects/vidalia>">Vidalia</a> so it supports the
1571)     new features, and planning for deployment.</li>
1572)     
1573)     <li>We need a flexible simulator framework for studying end-to-end
1574)     traffic confirmation attacks. Many researchers have whipped up ad hoc
1575)     simulators to support their intuition either that the attacks work
1576)     really well or that some defense works great. Can we build a simulator
1577)     that's clearly documented and open enough that everybody knows it's
1578)     giving a reasonable answer? This will spur a lot of new research.
1579)     See the entry <a href="#Research">below</a> on confirmation attacks for
1580)     details on the research side of this task &mdash; who knows, when it's
1581)     done maybe you can help write a paper or three also.</li>
1582)     

1583)     <li>Tor 0.1.1.x and later include support for hardware crypto
1584)     accelerators via OpenSSL. It has been lightly tested and is
1585)     possibly very buggy.  We're looking for more rigorous testing,

1586)     performance analysis, and optimally, code fixes to OpenSSL and

1587)     Tor if needed.</li>

1588)     
1589)     <li>Perform a security analysis of Tor with <a

1590)     href="https://secure.wikimedia.org/wikipedia/en/wiki/Fuzz_testing">"fuzz"</a>. Determine

1591)     if there are good fuzzing libraries out there for what we want. Win fame by
1592)     getting credit when we put out a new release because of you!</li>
1593)     
1594)     <li>Tor uses TCP for transport and TLS for link
1595)     encryption. This is nice and simple, but it means all cells
1596)     on a link are delayed when a single packet gets dropped, and
1597)     it means we can only reasonably support TCP streams. We have a <a

1598)     href="<page docs/faq>#TransportIPnotTCP">list

1599)     of reasons why we haven't shifted to UDP transport</a>, but it would
1600)     be great to see that list get shorter. We also have a proposed <a

1601)     href="<specblob>proposals/100-tor-spec-udp.txt">specification

1602)     for Tor and
1603)     UDP</a> &mdash; please let us know what's wrong with it.</li>
1604)     
1605)     <li>We're not that far from having IPv6 support for destination addresses
1606)     (at exit nodes). If you care strongly about IPv6, that's probably the
1607)     first place to start.</li>
1608)     
1609)     <li>We need a way to generate the website diagrams (for example, the "How
1610)     Tor Works" pictures on the <a href="<page about/overview>">overview page</a>
1611)     from source, so we can translate them as UTF-8 text rather than edit
1612)     them by hand with Gimp. We might want to
1613)     integrate this as an wml file so translations are easy and images are
1614)     generated in multiple languages whenever we build the website.</li>
1615)     
1616)     <li>How can we make the various LiveCD/USB systems easier
1617)     to maintain, improve, and document?  One example is <a

1618)     href="https://tails.boum.org/">The Amnesic Incognito Live

1619)     System</a>.
1620)     </li>
1621)     
1622)     <li>
1623)     Another anti-censorship project is to try to make Tor
1624)     more scanning-resistant.  Right now, an adversary can identify <a

1625)     href="<specblob>proposals/125-bridges.txt">Tor bridges</a>

1626)     just by trying to connect to them, following the Tor protocol,
1627)     and seeing if they respond.  To solve this, bridges could <a
1628)     href="<svnprojects>design-paper/blocking.html#tth_sEc9.3">act like
1629)     webservers</a> (HTTP or HTTPS) when contacted by port-scanning tools,
1630)     and not act like bridges until the user provides a bridge-specific key.
1631)     To start, check out Shane Pope's <a
1632)     href="http://dl.dropbox.com/u/37735/index.html">thesis and prototype</a>.
1633)     </li>
1634)     
1635)     </ol>
1636)     
1637)     <a id="Research"></a>
1638)     <h2><a class="anchor" href="#Research">Research</a></h2>
1639)     <ol>
1640)     <li>The "end-to-end traffic confirmation attack":
1641)     by watching traffic at Alice and at Bob, we can <a
1642)     href="http://freehaven.net/anonbib/#danezis:pet2004">compare
1643)     traffic signatures and become convinced that we're watching the same
1644)     stream</a>. So far Tor accepts this as a fact of life and assumes this
1645)     attack is trivial in all cases. First of all, is that actually true? How
1646)     much traffic of what sort of distribution is needed before the adversary
1647)     is confident he has won? Are there scenarios (e.g. not transmitting much)
1648)     that slow down the attack? Do some traffic padding or traffic shaping
1649)     schemes work better than others?</li>
1650)     <li>A related question is: Does running a relay/bridge provide additional
1651)     protection against these timing attacks? Can an external adversary that can't
1652)     see inside TLS links still recognize individual streams reliably?
1653)     Does the amount of traffic carried degrade this ability any? What if the
1654)     client-relay deliberately delayed upstream relayed traffic to create a queue
1655)     that could be used to mimic timings of client downstream traffic to make it
1656)     look like it was also relayed? This same queue could also be used for masking
1657)     timings in client upstream traffic with the techniques from <a
1658)     href="http://www.freehaven.net/anonbib/#ShWa-Timing06">adaptive padding</a>,
1659)     but without the need for additional traffic. Would such an interleaving of
1660)     client upstream traffic obscure timings for external adversaries? Would the
1661)     strategies need to be adjusted for asymmetric links? For example, on
1662)     asymmetric links, is it actually possible to differentiate client traffic from
1663)     natural bursts due to their asymmetric capacity? Or is it easier than
1664)     symmetric links for some other reason?</li>
1665)     <li>Repeat Murdoch and Danezis's <a
1666)     href="http://www.cl.cam.ac.uk/~sjm217/projects/anon/#torta">attack from
1667)     Oakland 05</a> on the current Tor network. See if you can learn why it
1668)     works well on some nodes and not well on others. (My theory is that the
1669)     fast nodes with spare capacity resist the attack better.) If that's true,
1670)     then experiment with the RelayBandwidthRate and RelayBandwidthBurst
1671)     options to run a relay that is used as a client while relaying the
1672)     attacker's traffic: as we crank down the RelayBandwidthRate, does the
1673)     attack get harder? What's the right ratio of RelayBandwidthRate to
1674)     actually capacity? Or is it a ratio at all? While we're at it, does a
1675)     much larger set of candidate relays increase the false positive rate
1676)     or other complexity for the attack? (The Tor network is now almost two
1677)     orders of magnitude larger than it was when they wrote their paper.) Be
1678)     sure to read <a href="http://freehaven.net/anonbib/#clog-the-queue">Don't
1679)     Clog the Queue</a> too.</li>
1680)     <li>The "routing zones attack": most of the literature thinks of
1681)     the network path between Alice and her entry node (and between the
1682)     exit node and Bob) as a single link on some graph. In practice,
1683)     though, the path traverses many autonomous systems (ASes), and <a
1684)     href="http://freehaven.net/anonbib/#feamster:wpes2004">it's not uncommon
1685)     that the same AS appears on both the entry path and the exit path</a>.
1686)     Unfortunately, to accurately predict whether a given Alice, entry,
1687)     exit, Bob quad will be dangerous, we need to download an entire Internet
1688)     routing zone and perform expensive operations on it. Are there practical
1689)     approximations, such as avoiding IP addresses in the same /8 network?</li>
1690)     <li>Other research questions regarding geographic diversity consider
1691)     the tradeoff between choosing an efficient circuit and choosing a random
1692)     circuit. Look at Stephen Rollyson's <a
1693)     href="http://swiki.cc.gatech.edu:8080/ugResearch/uploads/7/ImprovingTor.pdf">position
1694)     paper</a> on how to discard particularly slow choices without hurting
1695)     anonymity "too much". This line of reasoning needs more work and more
1696)     thinking, but it looks very promising.</li>
1697)     <li>Tor doesn't work very well when relays have asymmetric bandwidth
1698)     (e.g. cable or DSL). Because Tor has separate TCP connections between
1699)     each hop, if the incoming bytes are arriving just fine and the outgoing
1700)     bytes are all getting dropped on the floor, the TCP push-back mechanisms
1701)     don't really transmit this information back to the incoming streams.
1702)     Perhaps Tor should detect when it's dropping a lot of outgoing packets,
1703)     and rate-limit incoming streams to regulate this itself? I can imagine
1704)     a build-up and drop-off scheme where we pick a conservative rate-limit,
1705)     slowly increase it until we get lost packets, back off, repeat. We
1706)     need somebody who's good with networks to simulate this and help design
1707)     solutions; and/or we need to understand the extent of the performance
1708)     degradation, and use this as motivation to reconsider UDP transport.</li>
1709)     <li>A related topic is congestion control. Is our
1710)     current design sufficient once we have heavy use? Maybe
1711)     we should experiment with variable-sized windows rather
1712)     than fixed-size windows? That seemed to go well in an <a
1713)     href="http://www.psc.edu/networking/projects/hpn-ssh/theory.php">ssh
1714)     throughput experiment</a>. We'll need to measure and tweak, and maybe
1715)     overhaul if the results are good.</li>
1716)     <li>Our censorship-resistance goals include preventing
1717)     an attacker who's looking at Tor traffic on the wire from <a
1718)     href="<svnprojects>design-paper/blocking.html#sec:network-fingerprint">distinguishing
1719)     it from normal SSL traffic</a>. Obviously we can't achieve perfect
1720)     steganography and still remain usable, but for a first step we'd like to
1721)     block any attacks that can win by observing only a few packets. One of
1722)     the remaining attacks we haven't examined much is that Tor cells are 512
1723)     bytes, so the traffic on the wire may well be a multiple of 512 bytes.
1724)     How much does the batching and overhead in TLS records blur this on the
1725)     wire? Do different buffer flushing strategies in Tor affect this? Could
1726)     a bit of padding help a lot, or is this an attack we must accept?</li>
1727)     <li>Tor circuits are built one hop at a time, so in theory we have the
1728)     ability to make some streams exit from the second hop, some from the
1729)     third, and so on. This seems nice because it breaks up the set of exiting
1730)     streams that a given relay can see. But if we want each stream to be safe,
1731)     the "shortest" path should be at least 3 hops long by our current logic, so
1732)     the rest will be even longer. We need to examine this performance / security
1733)     tradeoff.</li>
1734)     <li>It's not that hard to DoS Tor relays or directory authorities. Are client
1735)     puzzles the right answer? What other practical approaches are there? Bonus
1736)     if they're backward-compatible with the current Tor protocol.</li>
1737)     <li>Programs like <a

1738)     href="<page torbutton/index>">Torbutton</a> aim to hide