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
38) <!-- web page and -->
39)     documentation into other

40)     languages. See the <a href="<page getinvolved/translation>">translation
41)     guidelines</a> if you want to help out. We especially need Arabic or
42)     Farsi translations, for the many Tor users in censored areas.</li>
43)     <li>Evaluate and document

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

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

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

48)     programs that interface to Tor</a>. Which ones are useful in which
49)     situations? Please help us test them out and document your results.</li>
50)     </ol>

51) 

52)     <a id="Advocacy"></a>
53)     <h2><a class="anchor" href="#Advocacy">Advocacy</a></h2>
54)     <ol>

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

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

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

60)     <a

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

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

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

64)     such as "Tor for Freedom!"</li>
65)     <li>Create a t-shirt design that incorporates "<a
66)     href="https://check.torproject.org/">Congratulations! You are using
67)     Tor!</a>" in any language.</li>

68)     </ol>

69) 

70) <!--

71)     <a id="gsoc"></a>
72)     <h2><a class="anchor" href="#gsoc">Google Summer of Code</a></h2>
73) 
74)     <p>
75)     Tor is also taking part in this year's <a
76)     href="https://www.google-melange.com/gsoc/homepage/google/gsoc2013">Google
77)     Summer of Code</a>! The criteria for this is a little different - either
78)     gender can apply but you need to be either <a
79)     href="https://www.google-melange.com/gsoc/document/show/gsoc_program/google/gsoc2013/help_page#2._Whos_eligible_to_participate_as_a">a
80)     present student or just graduated</a>.
81)     </p>
82) 
83)     <p>
84)     As mentioned above if you're eligible for either program then please apply
85)     for both! Google Summer of Code is a far, far larger program for us than
86)     OPW so your chances of being applied that way are considerably better.
87)     </p>
88) 
89)     <p>
90)     <b>See our page for <a href="<page about/gsoc>">Google Summer of Code</a>
91)     for more information.</b>
92)     </p>

93) -->

94) 

95)     <a id="Projects"></a>
96)     <h2><a class="anchor" href="#Projects">Projects</a></h2>

97) 

98)     <p>
99)     Below are a list of Tor related projects we're developing and/or
100)     maintaining. Most discussions happen on IRC so if you're interested in any
101)     of these (or you have a project idea of your own), then please <a

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

105)     </p>

106) 

107)     <p>
108)     For a presentation summarizing many of these projects see...
109)     </p>
110) 
111)     <div id="ecosystem_presentation">
112)       <a href="https://media.torproject.org/video/2013-11-t3am-damian-johnson.mp4">Tor Ecosystem</a> (<a href="https://svn.torproject.org/svn/projects/presentations/2013-11-t3am-tor-ecosystem.pdf">slides</a>)
113)     </div>
114) 
115)     <br /></br />
116) 

117)     <table id="projects">
118)       <tr>
119)         <th>Name</th>
120)         <th>Category</th>
121)         <th>Language</th>
122)         <th>Activity</th>
123)         <th>Contributors</th>
124)       </tr>

125) 

126)       <tr>
127)         <td><a href="#project-tor">Tor</a></td>
128)         <td>Core</td>
129)         <td>C</td>
130)         <td>Heavy</td>

131)         <td>nickm, athena, arma</td>

132)       </tr>

133) 

134)       <tr>

135)         <td>*<a href="#project-orchid">Orchid</a></td>

136)         <td>Core</td>
137)         <td>Java</td>

138)         <td>Moderate</td>

139)         <td>bleidl</td>
140)       </tr>
141) 
142)       <tr>

143)         <td><a href="#project-torbrowser">Tor Browser</a></td>

144)         <td>Bundle</td>

145)         <td>C, Scripting</td>

146)         <td>Moderate</td>

147)         <td>mikeperry, Erinn</td>

148)       </tr>

149) 

150)       <tr>

151)         <td><a href="#project-torbutton">Torbutton</a></td>
152)         <td>Browser Add-on</td>
153)         <td>Javascript</td>
154)         <td>Moderate</td>
155)         <td>mikeperry</td>

156)       </tr>

157) 

158)       <tr>

159)         <td><a href="#project-httpseverywhere">HTTPS Everywhere</a></td>
160)         <td>Browser Add-on</td>
161)         <td>Javascript</td>

162)         <td>Heavy</td>

163)         <td>pde, mikeperry</td>

164)       </tr>

165) 

166)       <tr>

167)         <td><a href="#project-vidalia">Vidalia</a></td>
168)         <td>User Interface</td>
169)         <td>C++, Qt</td>

170)         <td>None</td>

171)         <td>chiiph</td>
172)       </tr>

173) 

174)       <tr>

175)         <td><a href="#project-arm">Arm</a></td>
176)         <td>User Interface</td>
177)         <td>Python, Curses</td>

178)         <td>Light</td>

179)         <td>atagar</td>
180)       </tr>

181) 

182)       <tr>

183)         <td><a href="#project-orbot">Orbot</a></td>
184)         <td>User Interface</td>
185)         <td>Java</td>

186)         <td>Light</td>

187)         <td>n8fr8</td>

188)       </tr>

189) 

190)       <tr>

191)         <td><a href="#project-tails">Tails</a></td>
192)         <td>OS image</td>
193)         <td>Sys Admin</td>
194)         <td>Heavy</td>
195)         <td><a href="https://tails.boum.org/">#tails</a></td>

196)       </tr>

197) 

198)       <tr>

199)         <td><a href="#project-torramdisk">tor-ramdisk</a></td>
200)         <td>OS image</td>
201)         <td>Sys Admin</td>

202)         <td>None</td>

203)         <td>blueness</td>
204)       </tr>
205) 

206)       <tr>

207)         <td>*<a href="#project-torouter">Torouter</a></td>
208)         <td>OS image</td>
209)         <td>Sys Admin</td>

210)         <td>None</td>

211)         <td>ioerror</td>
212)       </tr>
213) 

214)       <tr>

215)         <td><a href="#project-torsocks">Torsocks</a></td>
216)         <td>Usability</td>
217)         <td>C</td>

218)         <td>Light</td>

219)         <td>ioerror, nickm</td>
220)       </tr>
221) 

222)       <tr>

223)         <td><a href="#project-torbirdy">TorBirdy</a></td>
224)         <td>Browser Add-on</td>
225)         <td>JavaScript</td>
226)         <td>Heavy</td>

227)         <td>Sukhbir (sukhe)</td>

228)       </tr>

229) 

230)       <tr>

231)         <td><a href="#project-obfsproxy">Obfsproxy</a></td>
232)         <td>Client Add-on</td>

233)         <td>Python</td>

234)         <td>Moderate</td>

235)         <td>asn</td>

236)       </tr>
237) 

238)       <tr>

239)         <td><a href="#project-flash-proxy">Flash Proxy</a></td>
240)         <td>Client Add-on</td>
241)         <td>Python, JavaScript, Go</td>

242)         <td>Heavy</td>

243)         <td>dcf, infinity0, aallai, jct</td>

244)       </tr>

245) 

246)       <tr>

247)         <td><a href="#project-shadow">Shadow</a></td>

248)         <td>Simulator</td>

249)         <td>C, Python</td>

250)         <td>Heavy</td>

251)         <td>robgjansen</td>
252)       </tr>

253) 

254)       <tr>

255)         <td><a href="#project-stem">Stem</a></td>

256)         <td>Library</td>
257)         <td>Python</td>
258)         <td>Heavy</td>

259)         <td>atagar</td>

260)       </tr>

261) 

262)       <tr>

263)         <td><a href="#project-txtorcon">Txtorcon</a></td>
264)         <td>Library</td>
265)         <td>Python, Twisted</td>

266)         <td>Moderate</td>

267)         <td>meejah</td>
268)       </tr>

269) 

270)       <tr>

271)         <td><a href="#project-tlsdate">Tlsdate</a></td>
272)         <td>Utility</td>
273)         <td>C</td>

274)         <td>Moderate</td>

275)         <td>ioerror</td>
276)       </tr>

277) 

278)       <tr>

279)         <td><a href="#project-metrics">Metrics</a></td>
280)         <td>Client Service</td>
281)         <td>Java</td>

282)         <td>Moderate</td>

283)         <td>karsten</td>
284)       </tr>

285) 

286)       <tr>

287)         <td><a href="#project-atlas">Atlas</a></td>
288)         <td>Client Service</td>
289)         <td>JavaScript</td>

290)         <td>Light</td>

291)         <td>hellais, karsten</td>

292)       </tr>

293) 

294)       <tr>
295)         <td><a href="#project-globe">Globe</a></td>
296)         <td>Client Service</td>
297)         <td>JavaScript</td>
298)         <td>Heavy</td>
299)         <td>Christian</td>
300)       </tr>
301) 

302)       <tr>

303)         <td><a href="#project-compass">Compass</a></td>
304)         <td>Client Service</td>
305)         <td>Python</td>

306)         <td>Light</td>

307)         <td>gsathya, karsten, cwacek</td>

308)       </tr>

309) 

310)       <tr>

311)         <td><a href="#project-onionoo">Onionoo</a></td>
312)         <td>Backend Service</td>
313)         <td>Java, Python</td>

314)         <td>Moderate</td>

315)         <td>karsten, gsathya</td>
316)       </tr>
317) 

318)       <tr>
319)         <td><a href="#project-doctor">DocTor</a></td>
320)         <td>Backend Service</td>
321)         <td>Python</td>
322)         <td>Light</td>
323)         <td>atagar</td>
324)       </tr>
325) 

326)       <tr>

327)         <td><a href="#project-weather">Weather</a></td>
328)         <td>Client Service</td>
329)         <td>Python</td>

330)         <td>None</td>

331)         <td>kaner</td>
332)       </tr>

333) 

334)       <tr>

335)         <td><a href="#project-gettor">GetTor</a></td>
336)         <td>Client Service</td>
337)         <td>Python</td>

338)         <td>None</td>

339)         <td>kaner</td>

340)       </tr>

341) 

342)       <tr>

343)         <td><a href="#project-torcheck">TorCheck</a></td>
344)         <td>Client Service</td>

345)         <td>Go</td>
346)         <td>Moderate</td>
347)         <td>Arlo</td>

348)       </tr>

349) 

350)       <tr>

351)         <td><a href="#project-bridgedb">BridgeDB</a></td>
352)         <td>Backend Service</td>
353)         <td>Python</td>

354)         <td>Light</td>

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

356)       </tr>

357) 

358)       <tr>

359)         <td><a href="#project-ooni-probe">Ooni Probe</a></td>

360)         <td>Scanner</td>
361)         <td>Python</td>

362)         <td>Moderate</td>

363)         <td>hellais, isis, ioerror</td>
364)       </tr>
365) 

366)       <tr>
367)         <td><a href="#project-torps">TorPS</a></td>
368)         <td>Backend Service</td>
369)         <td>Python</td>
370)         <td>Light</td>
371)         <td>Aaron Johnson</td>
372)       </tr>
373) 

374)       <tr>

375)         <td><a href="#project-torflow">TorFlow</a></td>
376)         <td>Backend Service</td>
377)         <td>Python</td>

378)         <td>None</td>

379)         <td>aagbsn, mikeperry</td>

380)       </tr>

381) 

382)       <tr>

383)         <td>*<a href="#project-torbel">TorBEL</a></td>
384)         <td>Backend Service</td>
385)         <td>Python</td>
386)         <td>None</td>
387)         <td>Sebastian</td>
388)       </tr>

389) 

390)       <tr>

391)         <td><a href="#project-tor2web">Tor2web</a></td>
392)         <td>Client Service</td>

393)         <td>Python</td>

394)         <td>Moderate</td>

395)         <td>evilaliv3, hellais</td>

396)       </tr>

397) 

398)       <tr>

399)         <td><a href="#project-anonbib">Anonbib</a></td>
400)         <td>Website</td>

401)         <td>Python</td>

402)         <td>Light</td>
403)         <td>arma, nickm</td>
404)       </tr>
405) 

406)     </table>

407) 

408)     <sub>
409)     * Project is still in an alpha state.
410)     </sub>

411) 

412)     <br /><br />

413) 

414)     <a id="project-tor"></a>
415)     <h3>Tor (<a href="https://gitweb.torproject.org/tor.git">code</a>, <a

416)     href="https://trac.torproject.org/projects/tor/report/12">bug

417)     tracker</a>)</h3>

418) 

419)     <p>
420)     Central project, providing the core software for using and participating in
421)     the Tor network. Numerous people contribute to the project to varying
422)     extents, but the chief architects are Nick Mathewson and Roger Dingledine.
423)     </p>

424) 

425)     <p>
426)     <b>Project Ideas:</b><br />

427)     <i><a href="#torCleanup">Tor Codebase Cleanup</a></i><br />

428)     <i><a href="#improveTorTestCoverage">Improve test coverage in Tor</a></i><br />
429)     <i><a href="#useMoreCores">Have the Tor daemon use more cores</a></i><br />
430)     <i><a href="#improveHiddenServices">Help improve Tor hidden services</a></i><br />
431)     <i><a href="#consensusDiffs">Implement consensus diffs</a></i><br />
432)     <i><a href="#improvedDnsSupport">Improved DNS support for Tor</a></i><br />
433)     <i><a href="#torSandboxing">Help improve Tor sandboxing</a></i>

434)     </p>

435) 

436)     <a id="project-orchid"></a>
437)     <h3><a href="https://github.com/subgraph/Orchid">Orchid</a> (<a
438)     href="https://github.com/subgraph/Orchid">code</a>, <a
439)     href="https://github.com/subgraph/Orchid/issues">bug

440)     tracker</a>)</h3>

441) 

442)     <p>

443)     Java implementation of Tor and successor to <a href="http://onioncoffee.sourceforge.net/">OnionCoffee</a>.

444)     </p>

445) 

446)     <a id="project-torbrowser"></a>

447)     <h3><a href="<page projects/torbrowser>">Tor Browser Bundle</a> (<a
448)     href="https://gitweb.torproject.org/torbrowser.git">code</a>, <a
449)     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

450)     tracker</a>, <a href="https://www.torproject.org/projects/torbrowser/design/">design doc</a>)</h3>
451) 

452)     <p>
453)     The Tor Browser Bundle is an easy-to-use portable package of Tor, Vidalia,

454)     Torbutton, and a Firefox fork preconfigured to work together out of

455)     the box. It contains a modified copy of Firefox that aims to resolve the
456)     privacy and security issues in mainline version.

457)     </p>

458) 
459)     <a id="project-torbutton"></a>
460)     <h3><a href="<page torbutton/index>">Torbutton</a> (<a
461)     href="https://gitweb.torproject.org/torbutton.git">code</a>, <a
462)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torbutton&order=priority">bug

463)     tracker</a>)</h3>

464) 

465)     <p>

466)     Firefox addon that addresses many of the client-side threats to browsing
467)     the Internet anonymously. Mike has since continued to adapt it to new
468)     threats, updated versions of Firefox, and possibly <a
469)     href="https://blog.torproject.org/blog/google-chrome-incognito-mode-tor-and-fingerprinting">Chrome
470)     as well</a>.

471)     </p>

472) 
473)     <a id="project-httpseverywhere"></a>
474)     <h3><a href="https://www.eff.org/https-everywhere">HTTPS Everywhere</a> (<a
475)     href="https://gitweb.torproject.org/https-everywhere.git">code</a>, <a
476)     href="https://trac.torproject.org/projects/tor/report/19">bug

477)     tracker</a>)</h3>

478) 

479)     <p>

480)     HTTPS Everywhere is a Firefox and Chrome extension that encrypts
481)     your communications with many major websites, making your browsing
482)     more secure.

483)     </p>

484) 

485)     <a id="project-vidalia"></a>
486)     <h3><a href="<page projects/vidalia>">Vidalia</a> (<a

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

488)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Vidalia&order=priority">bug
489)     tracker</a>)</h3>

490) 

491)     <p>
492)     The most commonly used user interface for Tor. Matt Edman started the
493)     project in 2006 and brought it to its current stable state. Development

494)     slowed for several years, though Tomás Touceda has since taken the
495)     lead with pushing the project forward.

496)     </p>

497) 

498)     <a id="project-arm"></a>

499)     <h3><a href="https://www.atagar.com/arm/">Arm</a> (<a

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

501)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=arm&order=priority">bug
502)     tracker</a>)</h3>

503) 

504)     <p>

505)     The anonymizing relay monitor (arm) is a terminal status monitor for Tor,
506)     intended for command-line aficionados, ssh connections, and anyone with a
507)     tty terminal. This works much like top does for system usage, providing
508)     real time statistics for bandwidth, resource usage, connections, and quite
509)     a bit more.

510)     </p>

511) 

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

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

515)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Orbot&order=priority">bug
516)     tracker</a>)</h3>

517) 
518)     <p>

519)     Provides Tor on the Android platform. The project is under active 
520)     development, updates to latest Tor releases, and working to stay up to 
521)     date with all changes in Android and mobile threats.

522)     </p>
523) 

524)     <p>
525)     <b>Project Ideas:</b><br />
526)     <i><a href="#orbotVPN">Orbot Android VPN</a></i><br />
527)     <i><a href="#orfox">Orfox - Firefox/Gecko-based Android Browser for Tor</a></i>
528)     </p>
529) 

530)     <a id="project-tails"></a>
531)     <h3><a href="https://tails.boum.org/">The Amnesic Incognito Live System</a> (<a

532)     href="https://git-tails.immerda.ch/tails/">code</a>, <a
533)     href="https://labs.riseup.net/code/projects/tails">bug

534)     tracker</a>)</h3>
535) 
536)     <p>
537)     The Amnesic Incognito Live System is a live CD/USB distribution
538)     preconfigured so that everything is safely routed through Tor and leaves no
539)     trace on the local system. This is a merger of the Amnesia and <a
540)     href="http://www.anonymityanywhere.com/incognito/">Incognito</a> projects,
541)     and still under very active development.
542)     </p>
543) 

544)     <a id="project-torramdisk"></a>
545)     <h3><a href="http://opensource.dyc.edu/tor-ramdisk">Tor-ramdisk</a> (<a

546)     href="https://gitweb.torproject.org/tor-ramdisk.git">code</a>, <a

547)     href="http://opensource.dyc.edu/tor-ramdisk-documentation">documentation</a>)</h3>

548) 
549)     <p>

550)     Tor-ramdisk is a uClibc-based micro Linux distribution whose sole
551)     purpose is to securely host a Tor server purely in RAM.

552)     </p>
553) 

554)     <a id="project-torouter"></a>
555)     <h3><a
556)     href="<wiki>doc/Torouter">Torouter</a> (<a

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

558)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torouter&order=priority">bug
559)     tracker</a>)</h3>
560) 
561)     <p>
562)     Project to provide an easy-to-use, embedded Tor instance for routers. This
563)     had high activity in late 2010, but has since been rather quiet.
564)     </p>
565) 
566)     <a id="project-torsocks"></a>

567)     <h3>Torsocks (<a

568)     href="https://gitweb.torproject.org/torsocks.git">code</a>, <a
569)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torify&order=priority">bug
570)     tracker</a>)</h3>
571) 

572)     <p>

573)     Utility for adapting other applications to work with Tor. Development has
574)     slowed and compatibility issues remain with some platforms, but it's
575)     otherwise feature complete.

576)     </p>

577) 

578)     <a id="project-torbirdy"></a>
579)     <h3>TorBirdy (<a
580)     href="https://github.com/ioerror/torbirdy">code</a>, <a
581)     href="https://trac.torproject.org/projects/tor/wiki/torbirdy/dev">bug
582)     tracker</a>)</h3>

583) 

584)     <p>
585)     TorBirdy is Torbutton for Thunderbird and related Mozilla mail clients.
586)     </p>

587) 

588)     <p>
589)     <b>Project Ideas:</b><br />
590)     <i><a href="#makeTorbirdyBetter">Make TorBirdy Better</a></i>
591)     </p>
592) 

593)     <a id="project-obfsproxy"></a>

594)     <h3><a href="<page projects/obfsproxy>">Obfsproxy</a> (<a

595)     href="https://gitweb.torproject.org/pluggable-transports/obfsproxy.git">code</a>,
596)     <a 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

597)     tracker</a>)</h3>

598) 

599)     <p>
600)     A proxy that shapes Tor traffic, making it harder for censors to detect and

601)     block Tor. This has both a C and python implementation.

602)     </p>

603) 

604)     <p>
605)     <b>Project Ideas:</b><br />
606)     <i><a href="#betterPluggableTransports">Build Better Pluggable Transports</a></i>
607)     </p>
608) 

609)     <a id="project-flash-proxy"></a>
610)     <h3><a href="https://crypto.stanford.edu/flashproxy/">Flash Proxy</a> (<a
611)     href="https://gitweb.torproject.org/flashproxy.git">code</a>, <a
612)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_information&status=needs_review&status=needs_revision&status=new&status=reopened&component=Flashproxy">bug
613)     tracker</a>)</h3>

614) 

615)     <p>
616)     Pluggable transport using proxies running in web browsers to defeat
617)     address-based blocking.
618)     </p>

619) 

620)     <a id="project-shadow"></a>
621)     <h3><a href="https://shadow.cs.umn.edu/">Shadow</a> (<a
622)     href="https://github.com/shadow">code</a>, <a
623)     href="https://github.com/shadow/shadow/issues">bug
624)     tracker</a>)</h3>

625) 

626)     <p>
627)     Shadow is a discrete-event network simulator that runs the real
628)     Tor software as a plug-in. Shadow is open-source software that enables
629)     accurate, efficient, controlled, and repeatable Tor experimentation.

630)     For another simulator, see <a
631)     href="http://crysp.uwaterloo.ca/software/exptor/">ExperimenTor</a>.

632)     </p>

633) 

634)     <a id="project-stem"></a>

635)     <h3><a href="https://stem.torproject.org/">Stem</a> (<a

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

637)     href="https://trac.torproject.org/projects/tor/wiki/doc/stem/bugs">bug

638)     tracker</a>)</h3>

639) 

640)     <p>

641)     Python controller library for scripts and controller applications using
642)     Tor.

643)     </p>

644) 

645)     <p>
646)     <b>Project Ideas:</b><br />

647)     <i><a href="#txtorcon-stemIntegration">Txtorcon/Stem Integration</a></i><br />

648)     <i><a href="#relayWebPanel">Relay Web Status Panel </a></i><br />

649)     </p>

650) 

651)     <a id="project-txtorcon"></a>

652)     <h3><a href="https://txtorcon.readthedocs.org">Txtorcon</a> (<a

653)     href="https://github.com/meejah/txtorcon">code</a>, <a

654)     href="https://github.com/meejah/txtorcon/issues">bug tracker</a>)</h3>

655) 

656)     <p>
657)     Twisted-based asynchronous Tor control protocol implementation. Includes
658)     unit-tests, examples, state-tracking code and configuration abstraction.
659)     Used by OONI and APAF.
660)     </p>

661) 

662)     <p>
663)     <b>Project Ideas:</b><br />
664)     <i><a href="#txtorcon-stemIntegration">Txtorcon/Stem Integration</a></i>
665)     </p>
666) 

667)     <a id="project-tlsdate"></a>
668)     <h3>Tlsdate (<a href="https://github.com/ioerror/tlsdate">code</a>)</h3>

669) 

670)     <p>
671)     tlsdate: secure parasitic rdate replacement
672)     </p>

673) 

674)     <p>
675)     tlsdate sets the local clock by securely connecting with TLS to remote
676)     servers and extracting the remote time out of the secure handshake. Unlike
677)     ntpdate, tlsdate uses TCP, for instance connecting to a remote HTTPS or TLS
678)     enabled service, and provides some protection against adversaries that try
679)     to feed you malicious time information.
680)     </p>

681) 

682)     <a id="project-metrics"></a>
683)     <h3><a href="https://metrics.torproject.org/">Metrics</a> (code: <a
684)     href="https://gitweb.torproject.org/metrics-db.git">db</a>, <a
685)     href="https://gitweb.torproject.org/metrics-utils.git">utils</a>, <a

686)     href="https://gitweb.torproject.org/metrics-web.git">web</a>)</h3>

687) 

688)     <p>
689)     Processing and analytics of consensus data, provided to users via the
690)     metrics portal. This has been under active development for several years by

691)     Karsten Loesing. See also <a
692)     href="https://gitweb.torproject.org/torperf.git">TorPerf</a>.

693)     </p>

694) 

695)     <a id="project-atlas"></a>
696)     <h3><a href="https://atlas.torproject.org/">Atlas</a> (<a
697)     href="https://gitweb.torproject.org/atlas.git">code</a>)</h3>

698) 

699)     <p>
700)     Atlas is a web application to discover Tor relays and bridges. It provides
701)     useful information on how relays are configured along with graphics about

702)     their past usage.

703)     </p>

704) 

705)     <p>

706)     This is the spiritual successor to <a
707)     href="https://gitweb.torproject.org/torstatus.git">TorStatus</a>, the <a

708)     href="https://svn.torproject.org/svn/torstatus/trunk/">original

709)     codebase</a> for which was written in PHP, and rewritten by students from
710)     Wesleyan as Django.

711)     </p>

712) 

713)     <a id="project-globe"></a>
714)     <h3><a href="http://globe.rndm.de/">Globe</a> (<a
715)     href="https://github.com/makepanic/globe">code</a>, <a
716)     href="https://github.com/makepanic/globe/issues">bug tracker</a>)</h3>
717) 
718)     <p>
719)     Globe is a web application that allows you to search for Tor relays and
720)     bridges. It gives you a detailed overview of properties and configurations
721)     of a relay or bridge.
722)     </p>
723) 

724)     <a id="project-compass"></a>
725)     <h3><a href="https://compass.torproject.org/">Compass</a> (<a
726)     href="https://gitweb.torproject.org/compass.git">code</a>, <a
727)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Compass&order=priority">bug
728)     tracker</a>)</h3>

729) 

730)     <p>
731)     Compass is a web and command line application that filters and
732)     aggregates the Tor relays based on various attributes.
733)     </p>

734) 
735)     <a id="project-onionoo"></a>
736)     <h3><a href="<page projects/onionoo>">Onionoo</a> (<a
737)     href="https://gitweb.torproject.org/onionoo.git">java codebase</a>, <a
738)     href="https://gitweb.torproject.org/pyonionoo.git">python

739)     codebase</a>, <a href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Onionoo&order=priority">bug tracker</a>)</h3>

740) 
741)     <p>
742)     Onionoo is a JSON based protocol to learn information about currently
743)     running Tor relays and bridges.
744)     </p>
745) 

746)     <a id="project-doctor"></a>
747)     <h3>DocTor (<a
748)     href="https://gitweb.torproject.org/doctor.git">code</a>, <a
749)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=DocTor&order=priority">bug
750)     tracker</a>)</h3>
751) 
752)     <p>
753)     DocTor is a notification service that monitors newly published descriptor
754)     information for issues. This is primarily a service to help the tor
755)     directory authority operators, but it also checks for a handful of other
756)     issues like sybil attacks.
757)     </p>
758) 

759)     <a id="project-weather"></a>

760)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/org/roadmaps/Weather">Weather</a> (<a

761)     href="https://gitweb.torproject.org/weather.git">code</a>, <a
762)     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
763)     tracker</a>)</h3>

764) 

765)     <p>
766)     Provides automatic notification to subscribed relay operators when their
767)     relay's unreachable. This underwent a rewrite by the <a
768)     href="http://hfoss.wesleyan.edu/">Wesleyan HFOSS team</a>, which went live
769)     in early 2011.
770)     </p>

771) 

772)     <a id="project-gettor"></a>

773)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/org/roadmaps/GetTor">GetTor</a> (<a

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

775)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=GetTor&order=priority">bug
776)     tracker</a>)</h3>

777) 

778)     <p>
779)     E-mail autoresponder providing Tor's packages over SMTP. This has been
780)     relatively unchanged for quite a while.
781)     </p>

782) 

783)     <a id="project-torcheck"></a>

784)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/org/roadmaps/TorCheck">TorCheck</a> (<a

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

786)     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
787)     tracker</a>)</h3>

788) 

789)     <p>

790)     Site for determining if the visitor is using Tor or not.

791)     </p>

792) 

793)     <a id="project-bridgedb"></a>

794)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/org/roadmaps/BridgeDB">BridgeDB</a> (<a

795)     href="https://gitweb.torproject.org/bridgedb.git">code</a>, <a
796)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=BridgeDB&order=priority">bug
797)     tracker</a>)</h3>

798) 

799)     <p>
800)     Backend bridge distributor, handling the various pools they're distributed
801)     in. This was actively developed until Fall of 2010.
802)     </p>

803) 
804)     <a id="project-ooni-probe"></a>

805)     <h3><a href="https://ooni.torproject.org/">Ooni Probe</a> (<a

806)     href="https://gitweb.torproject.org/ooni-probe.git">code</a>, <a
807)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Ooni&order=priority">bug
808)     tracker</a>)</h3>
809) 
810)     <p>
811)     Censorship scanner, checking your local connection for blocked or modified
812)     content.
813)     </p>
814) 

815)     <p>
816)     <b>Project Ideas:</b><br />

817)     <i><a href="#censorshipAnalyzer">Develop a Censorship Analyzer</a></i><br />
818)     <i><a href="#ooniprobePcapsSupport">Add Support for Reporting Pcaps to OoniBackend and OoniProbe</a></i>

819)     </p>
820) 

821)     <a id="project-torps"></a>
822)     <h3>TorPS</a> (<a href="https://github.com/torps/torps">code</a>)</h3>
823) 
824)     <p>
825)     The Tor Path Simulator (TorPS) is a tool for efficiently simulating
826)     path selection in Tor. It chooses circuits and assigns user streams to
827)     those circuits in the same way that Tor does. TorPS is fast enough to
828)     perform thousands of simulations over periods of months.
829)     </p>
830) 

831)     <a id="project-torflow"></a>

832)     <h3><a href="https://trac.torproject.org/projects/tor/wiki/org/roadmaps/TorFlow">TorFlow</a> (<a

833)     href="https://gitweb.torproject.org/torflow.git">code</a>, <a
834)     href="https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=needs_review&status=new&status=reopened&component=Torflow&order=priority">bug
835)     tracker</a>)</h3>

836) 

837)     <p>
838)     Library and collection of services for actively monitoring the Tor network.
839)     These include the Bandwidth Scanners (measuring throughput of relays) and
840)     SoaT (scans for malicious or misconfigured exit nodes). SoaT was last
841)     actively developed in the Summer of 2010, and the Bandwidth Scanners a few
842)     months later. Both have been under active use since then, but development
843)     has stopped.
844)     </p>

845) 

846)     <a id="project-torbel"></a>
847)     <h3><a

848)     href="https://blog.torproject.org/blog/torbel-tor-bulk-exit-list-tools">TorBEL</a> (<a
849)     href="https://gitweb.torproject.org/torbel.git">code</a>, <a

850)     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
851)     tracker</a>)</h3>

852) 

853)     <p>
854)     The Tor Bulk Exitlist provides a method of identifying if IPs belong to
855)     exit nodes or not. This is a replacement for TorDNSEL which is a stable
856)     (though unmaintained) Haskell application for this purpose. The initial
857)     version of TorBEL was started in GSOC 2010 but since then the project has
858)     been inactive.
859)     </p>

860) 
861)     <a id="project-tor2web"></a>
862)     <h3><a
863)     href="http://wiki.tor2web.org/index.php/Main_Page">Tor2web</a> (<a
864)     href="https://github.com/globaleaks/tor2web-3.0/wiki">code</a>)</h3>
865) 
866)     <p>
867)     Tor2web allows Internet users to browse websites running in <a
868)     href="<page docs/hidden-services>">Tor hidden services</a>. It trades
869)     user anonymity for usability by allowing anonymous content to be
870)     distributed to non-anonymous users.
871)     </p>
872) 

873)     <a id="project-anonbib"></a>
874)     <h3><a
875)     href="http://freehaven.net/anonbib/">Anonymity Bibliography</a> (<a
876)     href="https://gitweb.torproject.org/anonbib.git">code</a>)</h3>
877) 
878)     <p>

879)     Anonbib is a list of important papers in the field of anonymity. It's
880)     also a set of scripts to generate the website from Latex (bibtex). If
881)     we're missing any important papers, please let us know!

882)     </p>
883) 

884)     <a id="Coding"></a>
885)     <a id="Summer"></a>

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

887) 

888)     <p>

889)     You may find some of these projects to be good ideas for <a href="<page
890)     about/gsoc>">Google Summer of Code</a> and the <a
891)     href="https://live.gnome.org/OutreachProgramForWomen">Outreach Program for

892)     Women</a>. We have labelled each idea with how much work we expect it would
893)     be (effort level), how much clue you should start with (skill level),
894)     and which of our <a href="<page about/corepeople>">core developers</a>
895)     would be good mentors. If one or more of these ideas looks promising to
896)     you, please <a href="<page about/contact>">contact us</a> to discuss your
897)     plans rather than sending blind applications. You may also want to propose
898)     your own project idea &mdash; which often results in the best applications.

899)     </p>

900) 

901)     <ol>

902) 

903)     <a id="txtorcon-stemIntegration"></a>
904)     <li>
905)     <b>Txtorcon/Stem Integration</b>
906)     <br>
907)     Effort Level: <i>Medium</i>
908)     <br>
909)     Skill Level: <i>Medium</i>
910)     <br>
911)     Likely Mentors: <i>meejah, Damian (atagar)</i>
912)     <p>Txtorcon is a Twisted-based Python controller library, and Stem is a
913)     synchronous (threaded) one, also in Python. There is no need to have
914)     two implementations of (at least) the protocol parsing code. This
915)     project would entail eliminating duplication by leveraging Stem's
916)     parsing in txtorcon while keeping txtorcon's API the same (or at least
917)     close).</p>

918)     <p>Besides this you should identify some additional tasks to improve our
919)     controller space across these two libraries. Some ideas are...</p>
920)     <ul>
921)       <li>Write a tutorial for <a
922)       href="https://stem.torproject.org/tutorials.html">stem's tutorial
923)       page</a> demonstrating cross txtorcon/stem usage.</li>
924)       <li>Expand the txtorcon API to include functionality of <a
925)       href="https://gitweb.torproject.org/stem.git/blob/HEAD:/stem/control.py">stem's
926)       controller</a> that would be of interest to twisted users. All additions
927)       should include tests!</li>
928)       <li>Come up with some ideas of your own! We'd love to discuss them with
929)       you.</li>
930)     </ul>

931)     <p>This would very likely involve changes to both libraries, although
932)     most would be expected to be in txtorcon. meejah is available to
933)     mentor txtorcon changes, and Damian (atagar) can help with Stem.</p>
934)     <p>It would help if you're already familiar with event-based programming,
935)     bonus points if it's Twisted.</p>
936)     </li>
937) 

938)     <a id="relayWebPanel"></a>
939)     <li>

940)     <b>Relay Web Status Dashboard</b>

941)     <br>
942)     Effort Level: <i>Medium</i>
943)     <br>
944)     Skill Level: <i>Medium</i>
945)     <br>
946)     Likely Mentors: <i>Damian (atagar)</i>
947)     <p>
948)     Relay operators presently have a couple options for monitoring the status
949)     of their relay: <a
950)     href="https://www.torproject.org/getinvolved/volunteer.html.en#project-vidalia">Vidalia</a>
951)     which is a gui and <a href="https://www.atagar.com/arm/">arm</a> which uses
952)     curses. This project would be to make a new kind of monitor specifically
953)     for relay operators that provides a status dashboard site on localhost.
954)     </p>
955)     <p>
956)     The interface will likely <a
957)     href="https://www.atagar.com/arm/screenshots.php">borrow heavily from
958)     arm</a>, except of course in areas where we can improve upon it. Two
959)     important design constraints is that a localhost controller provides a
960)     bigger attack surface than guis or curses, so we should be a little more
961)     wary of what it does. This should be a read-only controller (ie, you can't
962)     *do* anything to the relay) and by default not surface any sensitive
963)     information (such as arm's connection panel).
964)     </p>
965)     <p>
966)     This project will likely include two parts: an AJAX site and a localhost
967)     daemon to fulfill those requests. <a
968)     href="https://stem.torproject.org/">Stem</a> is the backend of arm, and can
969)     be used to get everything you see in arm's interface (making it a natural
970)     choice for the daemon). That said, this project might entail some Stem
971)     improvements if we run across any gaps.
972)     </p>
973)     <p>

974)     This project has the potential for numerous users, one of which is an
975)     interface for <a
976)     href="https://www.torproject.org/getinvolved/volunteer.html.en#project-torouter">Torouter</a>.
977)     We should check if Torouter has any special use cases or constraints we
978)     should take into consideration.
979)     </p>
980)     <p>

981)     Applicants should be familiar with Python, JavaScript, and learn about
982)     <a href="https://stem.torproject.org/">Stem</a>. <b>As part of your
983)     application for this project please make both mockups of the interface and
984)     a proof of concept demo application using JS to surface something with
985)     Stem. <a
986)     href="https://trac.torproject.org/projects/tor/wiki/doc/stem/bugs">Involvement
987)     with Stem development</a> during the application process is also a big
988)     plus.</b>
989)     </p>
990)     </li>
991) 

992)     <a id="torCleanup"></a>

993)     <li>

994)     <b>Tor Codebase Cleanup</b>

995)     <br>

996)     Effort Level: <i>Low to High, depending on subproject chosen</i>

997)     <br>

998)     Skill Level: <i>Medium to High</i>

999)     <br>

1000)     Likely Mentors: <i>Nick (nickm)</i>

1001)     <p>

1002)     The Tor code is almost 10 years old in places, and we haven't always had
1003)     enough time or wisdom to write things as well as we could have.  Our unit
1004)     test coverage is shamefully low, and the dependency graph of our modules is
1005)     shamefully convoluted . We could use refactoring and unit tests!  Please
1006)     look through the Tor source code and look for ugly or tricky code or
1007)     dependencies -- the uglier and trickier the better -- and think about how
1008)     you could make the code look better, read better, and (subject to testing)
1009)     work better.

1010)     </p>

1011) 

1012)     <p>

1013)     If this is for a fun side-project, it would be great for you to work on
1014)     anything that can be made better and more tested.  For an internship-level
1015)     position, we'd hope that you could find a number of particularly tricky or
1016)     knotty piece of the code to clean up, and aim for resolving the ugliest
1017)     problems, not necessarily the easiest.

1018)     </p>

1019) 

1020)     <p>

1021)     For a big project here, it would be great to pick one of the major
1022)     "submodules" of Tor -- path selection, node discovery, directory authority
1023)     operations, directory service -- and refactor its interface completely, to
1024)     minify and codify its points of contact with the rest of Tor.

1025)     </p>

1026) 
1027)     <p>
1028)     <b>As part of your application for this project please identify one of the
1029)     thorniest Tor functions and submit a patch refactoring it to be better. If
1030)     you find this to be difficult then this likely isn't the project for
1031)     you.</b>
1032)     </p>

1033)     </li>

1034) 

1035)     <a id="betterPluggableTransports"></a>
1036)     <li>
1037)     <b>Build Better Pluggable Transports</b>
1038)     <br>
1039)     Effort Level: <i>Medium to High</i>
1040)     <br>
1041)     Skill Level: <i>Medium</i>
1042)     <br>

1043)     Likely Mentors: <i>Steven (sjmurdoch), Ximin (infinity0), George (asn)</i>

1044)     <p>

1045)     For Tor users in censored countries, we have a <a
1046)     href="https://www.torproject.org/docs/pluggable-transports.html.en">
1047)     pluggable transports</a> framework that uses external programs to bypass
1048)     censorship in different ways. Each of these have their own strengths and
1049)     weaknesses.

1050)     </p>
1051) 
1052)     <p>

1053)     We have deployed <a
1054)     href="https://www.torproject.org/projects/obfsproxy.html.en">obfsproxy</a>
1055)     and <a href="http://crypto.stanford.edu/flashproxy/">flashproxy</a> bridges
1056)     for a while, accessible using separately-installed pluggable transport
1057)     clients. Recently, we added this client support to the main Tor Browser
1058)     Bundle, and are adding more transports such as scramblesuit and fteproxy.
1059)     </p>
1060) 
1061)     <p>
1062)     There are several possible directions for this project. Ideas include:
1063)       <ol>
1064)         <li>Address gaps or weaknesses in our existing pluggable transports
1065)           <ul>
1066)             <li>Flashproxy: Add WebRTC support to traverse NATs.</li>
1067)             <li>Flashproxy: Improve the facilitator's resistance against DoS
1068)             and poisoning attacks.</li>
1069)           </ul>
1070)         </li>
1071)         <li>Build our pluggable transport combiner, that chains several
1072)         transports together to take advantage of orthogonal types of blocking
1073)         resistance.</li>
1074)         <li>Improve the UX for selecting the appropriate pluggable transport in
1075)         the new Tor Browser Bundle, whilst maintaining user security.</li>
1076)         <li>Implement a new pluggable transport that resists blocking in a
1077)         novel way.
1078)         <ul>
1079)           <li>Impersonate a voice-over-IP protocol</li>
1080)           <li>Impersonate HTTP <a
1081)           href="http://www.cs.utexas.edu/~amir/papers/parrot.pdf">sufficiently
1082)           well</a> that traffic will go through a HTTP-only proxy</li>
1083)           <li>Implement <a
1084)           href="http://cacr.uwaterloo.ca/techreports/2011/cacr2011-21.pdf">scanning
1085)           resistance</a></li>
1086)         </ul>
1087)         </li>
1088)       </ol>
1089)     </p>
1090) 
1091)     <p>
1092)     Applicants should be familiar with asynchronous/reactive programming, in
1093)     particular the <a href="https://twistedmatrix.com/">Twisted framework</a>
1094)     or something related. Most of the existing code is written in Python, with
1095)     some parts in JavaScript and Go, so you should know at least one of these.
1096)     You are invited to talk to us and ask questions, via our mailing lists
1097)     or IRC. <b>As part of your application, please contribute a patch that
1098)     implements a small feature or fixes a bug related to this area, e.g. <a
1099)     href="https://trac.torproject.org/projects/tor/query?status=!closed&component=Pluggable+transport">1</a>,
1100)     <a href="https://trac.torproject.org/projects/tor/query?status=!closed&component=Obfsproxy">2</a>,
1101)     <a href="https://trac.torproject.org/projects/tor/query?status=!closed&component=Flashproxy">3</a>.
1102)     </b>

1103)     </p>
1104) 

1105)     <a id="hsSearchEngine"></a>
1106)     <li>
1107)     <b>Search Engine for Hidden Services</b>
1108)     <br>
1109)     Effort Level: <i>Medium</i>
1110)     <br>
1111)     Skill Level: <i>Medium</i>
1112)     <br>
1113)     Likely Mentors: <i>George (asn)</i>
1114)     <p>
1115)     This project involves researching and developing a search engine for
1116)     Hidden Services.
1117)     </p>
1118) 
1119)     <p>
1120)     The student is expected to develop a search engine that can index
1121)     hidden services and reply to search queries. The student should also
1122)     develop a crawler that can search both "clear web" and hidden service
1123)     websites to find more addresses. The student is expected to use and
1124)     improve already existing search engine frameworks (e.g. YaCy), and not
1125)     reinvent the wheel when it's possible.
1126)     </p>
1127) 
1128)     <p>
1129)     The student should have a decent understanding of how search engines
1130)     work, what algorithms they use, and of any related open source tools
1131)     that are currently available.
1132)     </p>
1133) 

1134)     <a id="profileUDPTransport"></a>
1135)     <li>
1136)     <b>Profile UDP transport protocols</b>
1137)     <br>
1138)     Effort Level: <i>Medium to High</i>
1139)     <br>
1140)     Skill Level: <i>High</i>
1141)     <br>
1142)     Likely Mentors: <i>Steven (sjmurdoch)</i>
1143)     <p>
1144)     There are <a
1145)     href="https://research.torproject.org/techreports/datagram-comparison-2011-11-07.pdf">lots
1146)     of options</a> as to how Tor could send its data over UDP rather than TCP,
1147)     and some will likely perform significantly better than others. This project
1148)     will evaluate these options, so as to decide which should be used in future
1149)     versions of Tor. A first step will be to benchmark the various transport
1150)     protocols being considered, in terms of performance and also code quality,
1151)     including userspace TCP, <a
1152)     href="https://github.com/bittorrent/libutp">&mu;TP</a>, <a
1153)     href="http://en.wikipedia.org/wiki/Stream_Control_Transmission_Protocol">SCTP</a>
1154)     and <a href="http://curvecp.org/">CurveCP</a>. Initially these transport
1155)     protocols will be examined in isolation, but if the project progresses well
1156)     one or more could be integrated in Tor.
1157)     </p>
1158)     </li>
1159) 

1160)     <a id="httpsEverywhereRulesetTesting"></a>
1161)     <li>
1162)     <b>Incorporate Ruleset Testing into the HTTPS Everywhere release process</b>
1163)     <br>
1164)     Effort Level: <i>Medium</i>
1165)     <br>
1166)     Skill Level: <i>Medium</i>
1167)     <br>

1168)     Likely Mentors: <i>Peter Eckersley (pde), Micah Lee</i>

1169)     <p>
1170) Ondrej Mikle has implemented a codebase for testing HTTPS Everywhere rulesets
1171) by crawling pages that are affected by the ruleset (<a href="https://github.com/hiviah/https-everywhere-checker">repository</a>).
1172)     </p>
1173) 
1174)     <p>
1175) This codebase still has some rough edges that need to be smoothed over, but
1176) once those are done it should be incorporated into the HTTPS Everywhere build
1177) process, in order to improve the quality of our releases.
1178)     </p>
1179)     </li>
1180) 

1181)     <a id="censorshipAnalyzer"></a>
1182)     <li>
1183)     <b>Develop a Censorship Analyzer</b>
1184)     <br>
1185)     Effort Level: <i>Medium</i>
1186)     <br>
1187)     Skill Level: <i>Medium to High (depends on the implemented tests)</i>
1188)     <br>
1189)     Likely Mentors: <i>Philipp (phw)</i>
1190)     <p>
1191) Tor is documented to be blocked in <a
1192) href="https://censorshipwiki.torproject.org">several countries</a>. Analyzing
1193) these censorship incidents can be a tedious task; especially without access to
1194) machines inside the censoring networks. To make analysis easier, it would be
1195) great to have a lightweight analysis tool which can be run by censored users.
1196) This tool would conduct a number of networking tests and figure out if and how
1197) Tor could be blocked. The tool's final report should then somehow make it back
1198) to the Tor project.
1199)     </p>
1200) 
1201)     <p>
1202) The theory behind this tool is already <a

1203) href="http://www.cs.kau.se/philwint/pdf/foci2013.pdf">documented

1204) in a research paper</a>. What we now need is code! Implementing it would first
1205) mean getting familiar with <a href="https://ooni.torproject.org">OONI</a> and
1206) <a href="http://twistedmatrix.com/trac/">Twisted</a>. After that, the tool
1207) should be implemented as a number of OONI-specific networking tests.
1208)     </p>
1209)     </li>
1210) 

1211)     <a id="makeTorbirdyBetter"></a>
1212)     <li>
1213)     <b>Make TorBirdy Better</b>
1214)     <br>
1215)     Effort Level: <i>High</i>
1216)     <br>
1217)     Skill Level: <i>Medium</i>
1218)     <br>
1219)     Likely Mentors: <i>Sukhbir Singh (sukhe), Jacob Appelbaum (ioerror)</i>
1220)     <p>
1221) TorBirdy is an extension that configures Thunderbird to make connections over
1222) the Tor anonymity network. TorBirdy has been under development for quite a
1223) while but there are two known leaks that prevent it from being used by a wider
1224) audience. As part of this project, you will be working on plugging the known
1225) leaks and implementing a HTTP proxy.
1226)     </p>
1227) 
1228)     <p>
1229) <b>Part 1:</b> There are two patches pending with Mozilla that will plug the two known
1230) leaks in Thunderbird where the local time is disclosed through the date and the
1231) message-ID header. As part of your project, you will work on getting these
1232) patches finished/reimplemented and getting them merged with Mozilla. Please
1233) look at tickets <a
1234) href="https://trac.torproject.org/projects/tor/ticket/6314">#6314</a> and <a
1235) href="https://trac.torproject.org/projects/tor/ticket/6315">#6315</a> for more
1236) information.
1237)     </p>
1238) 
1239)     <p>
1240) <b>Part 2:</b> TorBirdy needs a HTTP proxy or a HTTP -&gt; SOCKS5 shim. Please look at
1241) ticket <a href="https://trac.torproject.org/projects/tor/ticket/6958">#6958</a>
1242) for more information. Note: this has to be done using JavaScript and not using
1243) an external proxy.
1244)     </p>
1245) 
1246)     <p>
1247) If time permits and you are awesome enough to finish the above two tasks, you
1248) will be working on the remaining TorBirdy tickets.
1249)     </p>
1250) 
1251)     <p>
1252) Applicants should be familiar with C++ and JavaScript. As part of your
1253) application for this project, please submit code samples for previous C++ and
1254) JavaScript projects that you have developed or point us to projects you have
1255) been involved with (links to a public Git/GitHub repository preferred). Prior
1256) extension development is a big plus and will be given preference during
1257) application ranking.
1258)     </p>
1259) 
1260)     <p>

1261) You may contact the mentors on IRC for more information. (sukhe on #tor-dev, #tor on irc.oftc.net)

1262)     </p>
1263)     </li>
1264) 

1265)     <a id="ooniprobePcapsSupport"></a>
1266)     <li>
1267)     <b>Add Support for Reporting Pcaps to OoniBackend and OoniProbe</b>
1268)     <br>
1269)     Effort Level: <i>Medium</i>
1270)     <br>
1271)     Skill Level: <i>Medium</i>
1272)     <br>
1273)     Likely Mentors: <i>Arturo (hellais), Aaron (aagbsn)</i>
1274)     <p>
1275) The feature should also add support for including only packet capture data that
1276) is relevant to the test being run. This means that the pcap should not contain
1277) all the data sniffed on the users machine, but only that which was generated
1278) and intended to be received by ooniprobe.
1279)     </p>
1280) 
1281)     <p>
1282) This can probably be implemented by setting up a tun/tap device and routing all
1283) the ooniprobe traffic through it and only capturing data sent and received from
1284) that device. The task for the student will also be that of doing research into
1285) what are possible strategies for doing this. <b><a
1286) href="https://trac.torproject.org/projects/tor/ticket/7416">For more
1287) information see ticket 7416.</a></b>
1288)     </p>
1289)     </li>
1290) 

1291)     <a id="orbotVPN"></a>
1292)     <li>
1293)     <b>Orbot Android VPN</b>
1294)     <br>
1295)     Effort Level: <i>Medium</i>
1296)     <br>
1297)     Skill Level: <i>High</i>
1298)     <br>
1299)     Likely Mentors: <i>Nathan (n8fr8)</i>
1300)     <p>
1301) Android offers the ability for any application to establish a
1302) VPNService through which all traffic on the device is sent. We want to
1303) implement this type of service in order to route all traffic through
1304) the Tor network. This is a feature that will be implemented directly
1305) into Orbot: Tor for Android if successfully implemented.
1306)     </p>
1307) 
1308)     <p>
1309) The deliverables for the project will be a working Android VPN
1310) implementation that routes traffic through Tor, and integration of VPN
1311) code into the Orbot app. There must also be time made for reporting on
1312) the project through blog posts, network auditing of tracking to ensure
1313) leakage is not occurring.
1314)     </p>
1315) 
1316)     <p>
1317) Useful links and documentation to study:
1318)     </p>
1319) 
1320)     <ul>
1321)       <li><a href="https://gitweb.torproject.org/orbot.git">Orbot</a></li>
1322)       <li><a href="http://developer.android.com/reference/android/net/VpnService.html">Android VPNService API</a></li>
1323)       <li><a href="https://github.com/guardianproject/OrbotVPN">Existing work on Orbot VPN</a></li>
1324)     </ul>
1325) 
1326)     <p>
1327) Applicant should have the ability to build Orbot application from
1328) source using Android SDK and NDK tools. A solid understanding of IP
1329) routing, iptables, netfilter and VPN protocols would also be very
1330) helpful. The ability to use Wireshark or other network monitoring
1331) software to test and verify solution is something that can be taught,
1332) but if you already know how, bonus! Finally, understanding how the
1333) exiting Tor software can be used with various transparent proxying
1334) configurations is a good first step to understanding this problem.
1335)     </p>
1336)     </li>
1337) 
1338)     <a id="orfox"></a>
1339)     <li>
1340)     <b>Orfox - Firefox/Gecko-based Android Browser for Tor</b>
1341)     <br>
1342)     Effort Level: <i>High</i>
1343)     <br>
1344)     Skill Level: <i>Medium</i>
1345)     <br>
1346)     Likely Mentors: <i>Nathan (n8fr8)</i>
1347)     <p>
1348) With almost 1 million downloads, our Orweb browser has been a popular
1349) solution for easily accessing the web via Tor or any other HTTP or
1350) SOCKS proxy, while also ensuring local data caches are cleared and
1351) cookies are properly managed. Orweb is based on WebView, which has its
1352) limitations unfortunately. We would like to move to a
1353) Firefox/Fennec/GeckoView based browser, and have created a prototype
1354) for it. Mozilla has begun releasing GeckoView as a standalone
1355) component, as well, but it needs more testing, debugging and work on
1356) integration into our streamlined browser app model. Our end goal is to
1357) have a mobile browser that matches Tor Browser in terms of privacy
1358) enhancing features and security.
1359)     </p>
1360) 
1361)     <p>
1362) The deliverables for the project are expected to be the creation of a
1363) alpha quality release of Orfox, a GeckoView-based browser with feature
1364) parity of Orweb browser. A bonus goal is to implement additional
1365) features and capabilities based on Tor Browser patches for
1366) Fennec/Mozilla core. Finally, as always, a required activity is a
1367) network audit testing of implemented solution with write-ups, reports
1368) posted publicly.
1369)     </p>
1370) 
1371)     <p>
1372) Useful links to review:
1373)     </p>
1374) 
1375)     <ul>
1376)       <li><a href="https://github.com/guardianproject/orfox">Orfox (gecko prototype)</a></li>
1377)       <li><a href="https://github.com/guardianproject/orweb">Orweb (production browser on WebView)</a></li>
1378)       <li><a href="http://starkravingfinkle.org/blog/2013/10/geckoview-embedding-gecko-in-your-android-application/">GeckoView info</a></li>
1379)       <li><a href="https://www.torproject.org/projects/torbrowser.html.en">Tor Browser (desktop)</a></li>
1380)     </ul>
1381) 
1382)     <p>
1383) Applicant should have the ability to build Fennec and GeckoView
1384) libraries from source using Android SDK and NDK. Some experince with
1385) browser security models and threats would be a useful background to
1386) have. Ability to do network audits to ensure browser proxying is not
1387) leaking DNS, media streams or other network traffic, as well as tests
1388) against common browser de-anonymizing attacks are necessary.
1389)     </p>
1390)     </li>
1391) 
1392)     <a id="improveTorTestCoverage"></a>
1393)     <li>
1394)     <b>Improve test coverage in Tor</b>
1395)     <br>
1396)     Effort Level: <i>Medium</i>
1397)     <br>
1398)     Skill Level: <i>Medium</i>
1399)     <br>
1400)     Likely Mentors: <i>Nick (nickm)</i>
1401)     <p>
1402) Right now, our unit test coverage with the tests we ship is around 30%
1403) -- only 30% of the executable lines in our source are reached by the
1404) unit tests.  Improving this test coverage could make Tor development
1405) much more reliable.
1406)     </p>
1407) 
1408)     <p>
1409) So we need better unit tests, and we need better integration tests too.
1410)     </p>
1411) 
1412)     <p>
1413) Improving unit tests would would involve refactoring functions to be more
1414) testable, and writing a bunch of unit tests.
1415)     </p>
1416) 
1417)     <p>
1418) Improving integratino tests would involve refactoring and improving
1419) the "chutney" program that launches a test tor network, and writing a
1420) bunch of tests to see what works and what doesn't work on such a
1421) network.  It could also involve writing tests using the library "<a
1422) href="https://stem.torproject.org/">stem</a>" to script individual clients on a
1423) Chutney network.
1424)     </p>
1425) 
1426)     <p>
1427) To get a feel for how testing works in Tor today, download Tor and
1428) Chutney, and make sure you can build Tor and use Chutney.  See how the
1429) unit tests work by skimming some of the test code in the src/test
1430) subdirectory.  Try computing test coverage (according to the
1431) instructions in the doc/HACKING file.
1432)     </p>
1433) 
1434)     <p>
1435) Also, have a look at the one current integration test that works on
1436) chutney today: it is a shell script distributed with Tor as
1437) src/test/test-tor-network.sh .  We probably don't want to have all of
1438) our integration tests be written as shell scripts, but it's interesting
1439) to see how one works.
1440)     </p>
1441) 
1442)     <p>
1443) If working on designs for an improved or refactored Chutney, watch out for <a
1444) href="http://www.joelonsoftware.com/articles/fog0000000018.html">"archicture
1445) astronautics"</a>: while it's important that we have a well-designed and
1446) maintainable Chutney architecture, it wouldn't be very useful if a good
1447) architecture were the <em>only</em> outcome here: we need tests too.
1448)     </p>
1449) 
1450)     <p>
1451) As part of the application process, please contribute a patch that makes
1452) a non-trivial improvement to chutney, and/or include a new test for some
1453) interesting Tor function. (Please pick a function that isn't completely
1454) easy to test.)
1455)     </p>
1456)     </li>
1457) 
1458)     <a id="useMoreCores"></a>
1459)     <li>
1460)     <b>Have the Tor daemon use more cores</b>
1461)     <br>
1462)     Effort Level: <i>Medium</i>
1463)     <br>
1464)     Skill Level: <i>Medium</i>
1465)     <br>
1466)     Likely Mentors: <i>Nick (nickm)</i>
1467)     <p>
1468) Right now, if you run a busy Tor server on a multicore computer, most of
1469) the cores are mostly unused.  We have a "cpuworker" mechanism to move
1470) expensive computations into worker threads, but that mechanism is
1471) currently only used for a small fraction of our cryptography.  Moving
1472) more work into the worker threads could improve performance immensely.
1473)     </p>
1474) 
1475)     <p>
1476) So it would be great to parallelize our cryptography more in order to
1477) better handle more cores.  See
1478) <a href="https://trac.torproject.org/projects/tor/wiki/org/projects/Tor/MultithreadedCrypto">MultithreadedCrypto</a>
1479) for some background info, and
1480) <a href="https://trac.torproject.org/projects/tor/ticket/7572">ticket 7572</a> for some subtickets
1481) on our tracker.
1482)     </p>
1483) 
1484)     <p>
1485) (If you're reading through the code to see how it works today, you will
1486) also want to have a look at the new implementation for cpuworkers
1487) described in <a href="https://trac.torproject.org/projects/tor/ticket/9682">9682</a>.)
1488)     </p>
1489) 
1490)     <p>
1491) Completing the implementation of ticket #7572 --which would move our
1492) circuit crypto onto separate threads-- could be a good summer project.
1493) Alternatively, moving all of the signature generation and verification
1494) code onto the cpuworkers could be fun.  In either case, you will have
1495) some important architectural decisions to make about how to minimize
1496) shared data between the main thread and the workers, how to avoid
1497) race conditions between them, and how to test it all to make sure it has
1498) no hidden failure cases.
1499)     </p>
1500) 
1501)     <p>
1502) As part of the application process for this project, please contribute a
1503) nontrivial patch to Tor -- ideally, one that will affect some part of
1504) the codebase that you want to work on.
1505)     </p>
1506)     </li>
1507) 
1508)     <a id="improveHiddenServices"></a>
1509)     <li>
1510)     <b>Help improve Tor hidden services</b>
1511)     <br>
1512)     Effort Level: <i>Medium</i>
1513)     <br>
1514)     Skill Level: <i>Medium</i>
1515)     <br>
1516)     Likely Mentors: <i>Nick (nickm)</i>
1517)     <p>
1518) We're working on a revamp of the entire Tor hidden service design to
1519) improve the security and reliability of the hidden service system.
1520)     </p>
1521) 
1522)     <p>
1523) This is a big project: see
1524) <a href="https://gitweb.torproject.org/torspec.git/blob_plain/refs/heads/master:/proposals/224-rend-spec-ng.txt">proposal
1525) 224</a> for the latest design.  Are you interested in implementing some
1526) part of that?
1527)     </p>
1528) 
1529)     <p>
1530) This is a very ambitious project, so we're deliberately not suggesting
1531) particular sub-topics.  If you're interested in participating, try to
1532) read and understand the <a
1533) href="https://gitweb.torproject.org/torspec.git/blob_plain/refs/heads/master:/rend-spec.txt">existing
1534) design</a> and the design proposal for the new design, and then talk to
1535) us about what part you want to work on.
1536)     </p>
1537) 
1538)     <p>
1539) As part of the application process for this project, please contribute a
1540) nontrivial patch to Tor -- ideally, one that will affect some part of
1541) the codebase that you want to work on.
1542)     </p>
1543)     </li>
1544) 
1545)     <a id="consensusDiffs"></a>
1546)     <li>
1547)     <b>Implement consensus diffs</b>
1548)     <br>
1549)     Effort Level: <i>Medium</i>
1550)     <br>
1551)     Skill Level: <i>Medium</i>
1552)     <br>
1553)     Likely Mentors: <i>Nick (nickm)</i>
1554)     <p>
1555) Right now, every few hours, a Tor client downloads a new signed "consensus
1556) document" that describes the state of the network.  Even though these
1557) documents are compressed, thisstill takes almost half a megabyte.
1558)     </p>
1559) 
1560)     <p>
1561) <a
1562) href="https://gitweb.torproject.org/torspec.git/blob_plain/refs/heads/master:/proposals/140-consensus-diffs.txt">Proposal
1563) 140</a> describes a design to save a lot of bandwidth by transferring
1564) compressed <a href="http://en.wikipedia.org/wiki/Diff">diff</a>s instead
1565) of transferring the entire consensus document.
1566)     </p>
1567) 
1568)     <p>
1569) That's an attractive idea, but it presents some programming challenges.
1570) We probably don't want to ship a 'diff' and 'patch' along with Tor.  Is
1571) there a free, <strong>safe</strong>, robust implementation of one of the
1572) good diff algorithms that we can use?
1573)     </p>
1574) 
1575)     <p>
1576) Alternatively, can we take advantage of regularities in the descriptor
1577) format in order to generate diffs more simply?
1578)     </p>
1579) 
1580)     <p>
1581) As part of the application process for this project, please contribute a
1582) nontrivial patch to Tor -- ideally, one that will affect some part of
1583) the codebase that you want to work on.  Make sure that your application
1584) describes which implementations of the diff and patch algorithms you
1585) intend to use, and that your coding samples show strong evidence that
1586) you can do secure string manipulation in C.
1587)     </p>
1588)     </li>
1589) 
1590)     <a id="improvedDnsSupport"></a>
1591)     <li>
1592)     <b>Improved DNS support for Tor</b>
1593)     <br>
1594)     Effort Level: <i>Medium</i>
1595)     <br>
1596)     Skill Level: <i>Medium</i>
1597)     <br>
1598)     Likely Mentors: <i>Nick (nickm)</i>
1599)     <p>
1600) Right now, you can only use Tor's DNS support to look up IPv4 and IPv6
1601) addresses, and to fetch PTR records.  But DNS can do so much more!
1602)     </p>
1603) 
1604)     <p>
1605) <a
1606) href="https://gitweb.torproject.org/torspec.git/blob_plain/refs/heads/master:/proposals/219-expanded-dns.txt">Proposal
1607) 219</a> describes some new cell types that Tor could use to support
1608) more types of DNS over Tor.
1609)     </p>
1610) 
1611)     <p>
1612) To see how Tor implements its existing DNS lookups, start by tracing the
1613) the connection_exit_begin_resolve() function in src/or/connection_edge.c ,
1614) and see how we pass these requests downwards through src/or/dns.c to the
1615) underlying resolver.  It's not too complicated, but there are some
1616) tricky parts to understand.
1617)     </p>
1618) 
1619)     <p>
1620) As part of the application process for this project, please contribute a
1621) nontrivial patch to Tor -- ideally, one that will affect some part of
1622) the codebase that you want to work on.
1623)     </p>
1624)     </li>
1625) 
1626)     <a id="torSandboxing"></a>
1627)     <li>
1628)     <b>Help improve Tor sandboxing</b>
1629)     <br>
1630)     Effort Level: <i>Medium</i>
1631)     <br>
1632)     Skill Level: <i>Medium</i>
1633)     <br>
1634)     Likely Mentors: <i>Nick (nickm)</i>
1635)     <p>
1636) The seccomp2 mechanism on Linux lets programs improve their robustness
1637) against unforseen bugs by running with restrictions on which system
1638) calls they can invoke and how they can call them.  This can help
1639) security a lot.
1640)     </p>
1641) 
1642)     <p>
1643) Thanks to a GSOC student from last year, we now have seccomp2 support on
1644) Linux, which we use to restrict the capabilities of the entire Tor
1645) process.  (For implementation details, see src/commmon/sandbox.c in the
1646) Tor source.)
1647)     </p>
1648) 
1649)     <p>
1650) But since the restrictions are done over the whole process, all pieces
1651) of the Tor code have permission to do things that only small parts of
1652) the Tor program need to do.  Also, since we use seccomp2, these
1653) restrictions only work on Linux.
1654)     </p>
1655) 
1656)     <p>
1657) It would be great to instead divide the main Tor program into multiple
1658) processes with a robust IPC mechanism and assign each process its own
1659) minimal set of privileges; and to have this work (as best we can) on
1660) systems that don't have seccomp2 (eg Windows, Mac).
1661)     </p>
1662) 
1663)     <p>
1664) Either of these could be a whole GSOC project.
1665)     </p>
1666) 
1667)     <p>
1668) To get started, make sure you understand the existing sandboxing code.
1669) If you're interested in splitting Tor into multiple processes, think
1670) about the architecture, and think about how we could reach this
1671) architecture without completely rewriting the codebase.  (Remember that
1672) even if you're focusing on Linux, Tor still needs to work on other
1673) operating systems.)
1674)     </p>
1675) 
1676)     <p>
1677) If you're interested in supporting more platforms, make sure you
1678) understand and can explain what sandboxing mechansisms you want to use,
1679) and what they're capable of.  (You might want to investigate the way
1680) that other open-source programs, like the Chrome web browser, do their
1681) sandboxing on different platforms.)
1682)     </p>
1683) 
1684)     <p>
1685) As part of the application process for this project, please contribute a
1686) nontrivial patch to Tor -- ideally, one that will affect some part of
1687) the codebase that you want to work on.
1688)     </p>
1689)     </li>
1690) 
1691) <!--
1692)     <a id=""></a>
1693)     <li>
1694)     <b></b>
1695)     <br>
1696)     Effort Level: <i>Medium</i>
1697)     <br>
1698)     Skill Level: <i>Medium</i>
1699)     <br>
1700)     Likely Mentors: <i>Damian (atagar)</i>
1701)     <p>
1702) 
1703)     </p>
1704) 
1705)     <p>
1706) 
1707)     </p>
1708)     </li>
1709) -->
1710) 

1711)     <li>
1712)     <b>Bring up new ideas!</b>

1713)     <br>

1714)     Don't like any of these? Look at the <a

1715)     href="/press/presskit/2008-12-19-roadmap-full.pdf">Tor development

1716)     roadmap</a> for more ideas, or just try out Tor, Vidalia, and Torbutton,
1717)     and find out what you think needs fixing.

1718)     Some of the <a href="<spectree>proposals">current proposals</a>

1719)     might also be short on developers.
1720)     </li>

1721) 

1722)     </ol>

1723) 

1724)     <a id="OtherCoding"></a>
1725)     <h2><a class="anchor" href="#OtherCoding">Other Coding and Design related ideas</a></h2>
1726)     <ol>
1727)     <li>Tor relays don't work well on Windows XP. On
1728)     Windows, Tor uses the standard <tt>select()</tt> system
1729)     call, which uses space in the non-page pool. This means
1730)     that a medium sized Tor relay will empty the non-page pool, <a

1731)     href="<wiki>doc/WindowsBufferProblems">causing

1732)     havoc and system crashes</a>. We should probably be using overlapped IO
1733)     instead. One solution would be to teach <a
1734)     href="http://www.monkey.org/~provos/libevent/">libevent</a> how to use
1735)     overlapped IO rather than select() on Windows, and then adapt Tor to
1736)     the new libevent interface. Christian King made a
1737)     <a href="https://svn.torproject.org/svn/libevent-urz/trunk/">good
1738)     start</a> on this in the summer of 2007.</li>

1739) 

1740)     <li>We need to actually start building our <a href="<page
1741)     docs/documentation>#DesignDoc">blocking-resistance design</a>. This involves
1742)     fleshing out the design, modifying many different pieces of Tor, adapting
1743)     <a href="<page projects/vidalia>">Vidalia</a> so it supports the
1744)     new features, and planning for deployment.</li>

1745) 

1746)     <li>We need a flexible simulator framework for studying end-to-end
1747)     traffic confirmation attacks. Many researchers have whipped up ad hoc
1748)     simulators to support their intuition either that the attacks work
1749)     really well or that some defense works great. Can we build a simulator
1750)     that's clearly documented and open enough that everybody knows it's
1751)     giving a reasonable answer? This will spur a lot of new research.
1752)     See the entry <a href="#Research">below</a> on confirmation attacks for
1753)     details on the research side of this task &mdash; who knows, when it's
1754)     done maybe you can help write a paper or three also.</li>

1755) 

1756)     <li>Tor 0.1.1.x and later include support for hardware crypto
1757)     accelerators via OpenSSL. It has been lightly tested and is
1758)     possibly very buggy.  We're looking for more rigorous testing,

1759)     performance analysis, and optimally, code fixes to OpenSSL and

1760)     Tor if needed.</li>

1761) 

1762)     <li>Write a <a
1763)     href="https://secure.wikimedia.org/wikipedia/en/wiki/Fuzz_testing">fuzzer</a>
1764)     for Tor to discover security vulnerabilities. Determine if there
1765)     are good fuzzing frameworks out there for what we want. Win fame by

1766)     getting credit when we put out a new release because of you!</li>

1767) 

1768)     <li>Tor uses TCP for transport and TLS for link
1769)     encryption. This is nice and simple, but it means all cells
1770)     on a link are delayed when a single packet gets dropped, and
1771)     it means we can only reasonably support TCP streams. We have a <a

1772)     href="<page docs/faq>#TransportIPnotTCP">list

1773)     of reasons why we haven't shifted to UDP transport</a>, but it would
1774)     be great to see that list get shorter. We also have a proposed <a

1775)     href="<specblob>proposals/100-tor-spec-udp.txt">specification

1776)     for Tor and
1777)     UDP</a> &mdash; please let us know what's wrong with it.</li>

1778) 

1779)     <li>We're not that far from having IPv6 support for destination addresses
1780)     (at exit nodes). If you care strongly about IPv6, that's probably the
1781)     first place to start.</li>

1782) 

1783)     <li>We need a way to generate the website diagrams (for example, the "How
1784)     Tor Works" pictures on the <a href="<page about/overview>">overview page</a>
1785)     from source, so we can translate them as UTF-8 text rather than edit
1786)     them by hand with Gimp. We might want to
1787)     integrate this as an wml file so translations are easy and images are
1788)     generated in multiple languages whenever we build the website.</li>

1789) 

1790)     <li>How can we make the various LiveCD/USB systems easier
1791)     to maintain, improve, and document?  One example is <a

1792)     href="https://tails.boum.org/">The Amnesic Incognito Live

1793)     System</a>.
1794)     </li>

1795) 

1796)     <li>
1797)     Another anti-censorship project is to try to make Tor
1798)     more scanning-resistant.  Right now, an adversary can identify <a

1799)     href="<specblob>proposals/125-bridges.txt">Tor bridges</a>

1800)     just by trying to connect to them, following the Tor protocol,
1801)     and seeing if they respond.  To solve this, bridges could <a
1802)     href="<svnprojects>design-paper/blocking.html#tth_sEc9.3">act like
1803)     webservers</a> (HTTP or HTTPS) when contacted by port-scanning tools,
1804)     and not act like bridges until the user provides a bridge-specific key.
1805)     To start, check out Shane Pope's <a
1806)     href="http://dl.dropbox.com/u/37735/index.html">thesis and prototype</a>.
1807)     </li>

1808) 

1809)     </ol>

1810) 

1811)     <a id="Research"></a>
1812)     <h2><a class="anchor" href="#Research">Research</a></h2>
1813)     <ol>
1814)     <li>The "end-to-end traffic confirmation attack":
1815)     by watching traffic at Alice and at Bob, we can <a
1816)     href="http://freehaven.net/anonbib/#danezis:pet2004">compare
1817)     traffic signatures and become convinced that we're watching the same
1818)     stream</a>. So far Tor accepts this as a fact of life and assumes this
1819)     attack is trivial in all cases. First of all, is that actually true? How
1820)     much traffic of what sort of distribution is needed before the adversary
1821)     is confident he has won? Are there scenarios (e.g. not transmitting much)
1822)     that slow down the attack? Do some traffic padding or traffic shaping
1823)     schemes work better than others?</li>
1824)     <li>A related question is: Does running a relay/bridge provide additional
1825)     protection against these timing attacks? Can an external adversary that can't
1826)     see inside TLS links still recognize individual streams reliably?
1827)     Does the amount of traffic carried degrade this ability any? What if the
1828)     client-relay deliberately delayed upstream relayed traffic to create a queue
1829)     that could be used to mimic timings of client downstream traffic to make it
1830)     look like it was also relayed? This same queue could also be used for masking
1831)     timings in client upstream traffic with the techniques from <a
1832)     href="http://www.freehaven.net/anonbib/#ShWa-Timing06">adaptive padding</a>,
1833)     but without the need for additional traffic. Would such an interleaving of
1834)     client upstream traffic obscure timings for external adversaries? Would the
1835)     strategies need to be adjusted for asymmetric links? For example, on
1836)     asymmetric links, is it actually possible to differentiate client traffic from
1837)     natural bursts due to their asymmetric capacity? Or is it easier than
1838)     symmetric links for some other reason?</li>
1839)     <li>Repeat Murdoch and Danezis's <a
1840)     href="http://www.cl.cam.ac.uk/~sjm217/projects/anon/#torta">attack from
1841)     Oakland 05</a> on the current Tor network. See if you can learn why it
1842)     works well on some nodes and not well on others. (My theory is that the
1843)     fast nodes with spare capacity resist the attack better.) If that's true,
1844)     then experiment with the RelayBandwidthRate and RelayBandwidthBurst
1845)     options to run a relay that is used as a client while relaying the
1846)     attacker's traffic: as we crank down the RelayBandwidthRate, does the
1847)     attack get harder? What's the right ratio of RelayBandwidthRate to
1848)     actually capacity? Or is it a ratio at all? While we're at it, does a
1849)     much larger set of candidate relays increase the false positive rate
1850)     or other complexity for the attack? (The Tor network is now almost two
1851)     orders of magnitude larger than it was when they wrote their paper.) Be
1852)     sure to read <a href="http://freehaven.net/anonbib/#clog-the-queue">Don't
1853)     Clog the Queue</a> too.</li>
1854)     <li>The "routing zones attack": most of the literature thinks of
1855)     the network path between Alice and her entry node (and between the
1856)     exit node and Bob) as a single link on some graph. In practice,
1857)     though, the path traverses many autonomous systems (ASes), and <a
1858)     href="http://freehaven.net/anonbib/#feamster:wpes2004">it's not uncommon
1859)     that the same AS appears on both the entry path and the exit path</a>.
1860)     Unfortunately, to accurately predict whether a given Alice, entry,
1861)     exit, Bob quad will be dangerous, we need to download an entire Internet
1862)     routing zone and perform expensive operations on it. Are there practical
1863)     approximations, such as avoiding IP addresses in the same /8 network?</li>
1864)     <li>Other research questions regarding geographic diversity consider
1865)     the tradeoff between choosing an efficient circuit and choosing a random
1866)     circuit. Look at Stephen Rollyson's <a
1867)     href="http://swiki.cc.gatech.edu:8080/ugResearch/uploads/7/ImprovingTor.pdf">position
1868)     paper</a> on how to discard particularly slow choices without hurting
1869)     anonymity "too much". This line of reasoning needs more work and more
1870)     thinking, but it looks very promising.</li>
1871)     <li>Tor doesn't work very well when relays have asymmetric bandwidth
1872)     (e.g. cable or DSL). Because Tor has separate TCP connections between
1873)     each hop, if the incoming bytes are arriving just fine and the outgoing
1874)     bytes are all getting dropped on the floor, the TCP push-back mechanisms
1875)     don't really transmit this information back to the incoming streams.
1876)     Perhaps Tor should detect when it's dropping a lot of outgoing packets,
1877)     and rate-limit incoming streams to regulate this itself? I can imagine
1878)     a build-up and drop-off scheme where we pick a conservative rate-limit,
1879)     slowly increase it until we get lost packets, back off, repeat. We
1880)     need somebody who's good with networks to simulate this and help design
1881)     solutions; and/or we need to understand the extent of the performance
1882)     degradation, and use this as motivation to reconsider UDP transport.</li>
1883)     <li>A related topic is congestion control. Is our
1884)     current design sufficient once we have heavy use? Maybe
1885)     we should experiment with variable-sized windows rather
1886)     than fixed-size windows? That seemed to go well in an <a

1887)     href="http://www.psc.edu/index.php/hpn-ssh/638">ssh

1888)     throughput experiment</a>. We'll need to measure and tweak, and maybe
1889)     overhaul if the results are good.</li>
1890)     <li>Our censorship-resistance goals include preventing
1891)     an attacker who's looking at Tor traffic on the wire from <a
1892)     href="<svnprojects>design-paper/blocking.html#sec:network-fingerprint">distinguishing
1893)     it from normal SSL traffic</a>. Obviously we can't achieve perfect
1894)     steganography and still remain usable, but for a first step we'd like to
1895)     block any attacks that can win by observing only a few packets. One of
1896)     the remaining attacks we haven't examined much is that Tor cells are 512
1897)     bytes, so the traffic on the wire may well be a multiple of 512 bytes.
1898)     How much does the batching and overhead in TLS records blur this on the
1899)     wire? Do different buffer flushing strategies in Tor affect this? Could
1900)     a bit of padding help a lot, or is this an attack we must accept?</li>
1901)     <li>Tor circuits are built one hop at a time, so in theory we have the
1902)     ability to make some streams exit from the second hop, some from the
1903)     third, and so on. This seems nice because it breaks up the set of exiting
1904)     streams that a given relay can see. But if we want each stream to be safe,
1905)     the "shortest" path should be at least 3 hops long by our current logic, so
1906)     the rest will be even longer. We need to examine this performance / security
1907)     tradeoff.</li>
1908)     <li>It's not that hard to DoS Tor relays or directory authorities. Are client
1909)     puzzles the right answer? What other practical approaches are there? Bonus
1910)     if they're backward-compatible with the current Tor protocol.</li>
1911)     <li>Programs like <a

1912)     href="<page torbutton/index>">Torbutton</a> aim to hide

1913)     your browser's UserAgent string by replacing it with a uniform answer for
1914)     every Tor user. That way the attacker can't splinter Tor's anonymity set
1915)     by looking at that header. It tries to pick a string that is commonly used
1916)     by non-Tor users too, so it doesn't stand out. Question one: how badly
1917)     do we hurt ourselves by periodically updating the version of Firefox
1918)     that Torbutton claims to be? If we update it too often, we splinter the
1919)     anonymity sets ourselves. If we don't update it often enough, then all the
1920)     Tor users stand out because they claim to be running a quite old version
1921)     of Firefox. The answer here probably depends on the Firefox versions seen
1922)     in the wild. Question two: periodically people ask us to cycle through N
1923)     UserAgent strings rather than stick with one. Does this approach help,
1924)     hurt, or not matter? Consider: cookies and recognizing Torbutton users
1925)     by their rotating UserAgents; malicious websites who only attack certain
1926)     browsers; and whether the answers to question one impact this answer.
1927)     </li>
1928)     <li>How many bridge relays do you need to know to maintain
1929)     reachability? We should measure the churn in our bridges. If there is
1930)     lots of churn, are there ways to keep bridge users more likely to stay
1931)     connected?
1932)     </li>
1933)     </ol>

1934) 

1935)     <p>
1936)     <a href="<page about/contact>">Let us know</a> if you've made progress on any
1937)     of these!
1938)     </p>
1939)   </div>
1940)   <!-- END MAINCOL -->
1941)   <div id = "sidecol">
1942) #include "side.wmi"
1943) #include "info.wmi"
1944)   </div>
1945)   <!-- END SIDECOL -->
1946) </div>
1947) <!-- END CONTENT -->