tor-webwml.git

@@ -11,7 +11,7 @@

      <address><email>mikeperry.fscked/org</email></address>

     </affiliation>

    </author>

-   <pubdate>Apr 10 2010</pubdate>

+   <pubdate>Jun 28 2010</pubdate>

  </articleinfo>

 <sect1>

@@ -1981,7 +1981,7 @@ Google Captcha</title>

 <para>

-Google's earch engine has rate limiting features that cause it to

+Google's search engine has rate limiting features that cause it to

 <ulink

 url="http://googleonlinesecurity.blogspot.com/2007/07/reason-behind-were-sorry-message.html">present

 captchas</ulink> and sometimes even outright ban IPs that issue large numbers

@@ -2065,13 +2065,16 @@ is currently not exposed via the preferences UI.

 Torbutton has to work around a number of Firefox bugs that impact its

 security. Most of these are mentioned elsewhere in this document, but they

-have also been gathered here for reference. Several of these have fixes in

-Firefox3.0/trunk, but are listed because they still have not been backported

-to FF2.0. In order of decreasing severity, they are:

+have also been gathered here for reference. In order of decreasing severity,

+they are:

    </para>

    <orderedlist>

+<!--

+

+XXX: We should just consider this one fixed. FF3.0 is pretty much at EOL.

+

    <listitem><ulink

 url="https://bugzilla.mozilla.org/show_bug.cgi?id=392274">Bug 392274 - Timezone

 config/chrome API</ulink>

@@ -2094,27 +2097,51 @@ fulfill its <link linkend="location">Location Neutrality</link> requirement.

    </para>

    </listitem>

-<!--

-FIXME: This one is fixed, but we need to make use of the new API in FF3.5

+-->

+    <listitem><ulink

+url="https://bugzilla.mozilla.org/show_bug.cgi?id=429070">Bug 429070 - exposing

+Components.interfaces to untrusted content leaks information about installed

+extensions</ulink>

+     <para>

+<ulink url="http://pseudo-flaw.net/">Gregory Fleischer</ulink> demonstrated at Defcon 17 that these interfaces can

+also be used to <ulink

+url="http://pseudo-flaw.net/tor/torbutton/fingerprint-firefox.html">fingerprint

+Firefox down the to the minor version</ulink>. Note that his test has not been

+updated since 3.5.3, hence it reports 3.5.3 for more recent Firefoxes. This

+bug interferes with Torbutton's ability to satisfy its <link

+linkend="setpreservation">Anonymity Set Preservation</link> requirement.

+     </para>

+    </listitem>

    <listitem><ulink

-url="https://bugzilla.mozilla.org/show_bug.cgi?id=436250">Bug 436250 - Livemarks can't be

-disabled at runtime</ulink>

+url="https://bugzilla.mozilla.org/show_bug.cgi?id=280661">Bug 280661 - SOCKS proxy server

+connection timeout hard-coded</ulink>

     <para>

-The RSS Feed based "Livemarks"/"Live Bookmarks" update frequency is controlled

-by the pref <command>browser.bookmarks.livemark_refresh_seconds</command>.

-However, changing this preference does not cancel any pending timers, which

-means that at least one livemarks pref fetch will happen over Tor, and once

-this pref is set to disable livemarks for Tor, changing it back will never

-cause the service to start back up again. The

-leakage of Livemarks interferes with Torbutton's ability to fulfill

-the <link linkend="isolation">Network Isolation</link> requirement.

+This bug prevents us from using the Firefox SOCKS layer directly, and

+currently requires us to ship an auxiliary HTTP proxy called <ulink

+url="http://www.pps.jussieu.fr/~jch/software/polipo/">Polipo</ulink>. If this

+patch were landed, we would no longer need to ship Polipo, which has a number

+of privacy and security issues of its own (in addition to being unmaintained).

     </para>

    </listitem>

--->

+   <listitem><ulink

+url="https://bugzilla.mozilla.org/show_bug.cgi?id=418986">Bug 418986 - window.screen

+provides a large amount of identifiable information</ulink>

+   <para>

+

+As <link linkend="fingerprinting">mentioned above</link>, a large amount of

+information is available from <ulink

+url="http://developer.mozilla.org/en/docs/DOM:window.screen">window.screen</ulink>.

+Currently, there is no way to obscure this information without Javascript

+hooking. This bug is a feature request to provide some other method to change

+these values. This bug interferes with Torbutton's ability to fulfill its

+<link linkend="setpreservation">Anonymity Set Preservation</link>

+requirement.

+   </para>

+   </listitem>

    <listitem><ulink

 url="https://bugzilla.mozilla.org/show_bug.cgi?id=435159">Bug 435159 -

 nsNSSCertificateDB::DeleteCertificate has race conditions</ulink>

@@ -2134,6 +2161,26 @@ feature.

       </para>

      </listitem>

+     <listitem><ulink

+url="https://bugzilla.mozilla.org/show_bug.cgi?id=575230">Bug 575230 - Provide option to

+reduce precision of Date()</ulink>

+      <para>

+

+Currently it is possible to <ulink

+url="http://arstechnica.com/tech-policy/news/2010/02/firm-uses-typing-cadence-to-finger-unauthorized-users.ars">fingerprint

+users based on their typing cadence</ulink> using the high precision timer

+available to javascript. Using this same precision, it is possible to compute

+an identifier based upon the clock drift of the client from some nominal

+source. The latter is not much of a concern for Tor users, as the variable

+delay to load and run a page is measured on the order of seconds, but the high

+precision timer can still be used to fingerprint aspects of a browser's

+javascript engine and processor, and apparently also a user's typing cadence.

+This bug hinders Torbutton's ability to satisfy its <link

+linkend="setpreservation">Anonymity Set Preservation</link> requirement.

+

+      </para>

+     </listitem>

+

      <listitem><ulink

 url="https://bugzilla.mozilla.org/show_bug.cgi?id=409737">Bug 409737 -

 javascript.enabled and docShell.allowJavascript do not disable all event

@@ -2350,20 +2399,6 @@ livemarks fetches.

     </para>

     </listitem>

 -->

-   <listitem><ulink

-url="https://bugzilla.mozilla.org/show_bug.cgi?id=418986">Bug 418986 - window.screen

-provides a large amount of identifiable information</ulink>

-   <para>

-

-As <link linkend="fingerprinting">mentioned above</link>, a large amount of

-information is available from <ulink

-url="http://developer.mozilla.org/en/docs/DOM:window.screen">window.screen</ulink>.

-Currently, there is no way to obscure this information without Javascript

-hooking. This bug is a feature request to provide some other method to change

-these values.

-

-   </para>

-   </listitem>

      <listitem><ulink

 url="https://bugzilla.mozilla.org/show_bug.cgi?id=309524">Bug 309524</ulink>

@@ -2399,6 +2434,10 @@ Williams.

      </para>

      </listitem>

+<!--

+

+XXX: This is likely fixed with nsICrypto.logout()

+

      <listitem><ulink

 url="https://bugzilla.mozilla.org/show_bug.cgi?id=448747">Bug 448747 -

 Provide Mechanism to clear TLS Session IDs</ulink>

@@ -2414,6 +2453,7 @@ thing.

      </para>

      </listitem>

+-->

    <listitem><ulink

 url="https://bugzilla.mozilla.org/show_bug.cgi?id=419598">Bug 419598 - 'var

@@ -1,7 +1,7 @@

 <?xml version="1.0" encoding="UTF-8"?>

 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

-<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Torbutton Design Documentation</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /></head><body><div class="article" title="Torbutton Design Documentation"><div class="titlepage"><div><div><h2 class="title"><a id="design"></a>Torbutton Design Documentation</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Mike</span> <span class="surname">Perry</span></h3><div class="affiliation"><div class="address"><p><code class="email">&lt;<a class="email" href="mailto:mikeperry.fscked/org">mikeperry.fscked/org</a>&gt;</code></p></div></div></div></div><div><p class="pubdate">Apr 10 2010</p></div></div><hr /></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="#id2945584">1. Introduction</a></span></dt><dd><dl><dt><span class="sect2"><a href="#adversary">1.1. Adversary Model</a></span></dt><dt><span class="sect2"><a href="#requirements">1.2. Torbutton Requirements</a></span></dt><dt><span class="sect2"><a href="#layout">1.3. Extension Layout</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2976187">2. Components</a></span></dt><dd><dl><dt><span class="sect2"><a href="#id2969623">2.1. Hooked Components</a></span></dt><dt><span class="sect2"><a href="#id2952263">2.2. New Components</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2962049">3. Chrome</a></span></dt><dd><dl><dt><span class="sect2"><a href="#browseroverlay">3.1. Browser Overlay - torbutton.xul</a></span></dt><dt><span class="sect2"><a href="#id2941767">3.2. Preferences Window - preferences.xul</a></span></dt><dt><span class="sect2"><a href="#id2976170">3.3. Other Windows</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2977751">4. Toggle Code Path</a></span></dt><dd><dl><dt><span class="sect2"><a href="#id2944154">4.1. Button Click</a></span></dt><dt><span class="sect2"><a href="#id2978704">4.2. Proxy Update</a></span></dt><dt><span class="sect2"><a href="#id2945348">4.3. Settings Update</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2966553">5. Description of Options</a></span></dt><dd><dl><dt><span class="sect2"><a href="#id2948284">5.1. Test Settings</a></span></dt><dt><span class="sect2"><a href="#plugins">5.2. Disable plugins on Tor Usage (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2965289">5.3. Isolate Dynamic Content to Tor State (crucial)</a></span></dt><dt><span class="sect2"><a href="#jshooks">5.4. Hook Dangerous Javascript</a></span></dt><dt><span class="sect2"><a href="#id2964952">5.5. Resize windows to multiples of 50px during Tor usage (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2977086">5.6. Disable Updates During Tor</a></span></dt><dt><span class="sect2"><a href="#id2937206">5.7. Redirect Torbutton Updates Via Tor (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2937250">5.8. Disable Search Suggestions during Tor (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2937289">5.9. Disable livemarks updates during Tor usage (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2937361">5.10. Block Tor/Non-Tor access to network from file:// urls (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2937433">5.11. Close all Tor/Non-Tor tabs and windows on toggle (optional)</a></span></dt><dt><span class="sect2"><a href="#id2937514">5.12. Isolate Access to History navigation to Tor state (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2937598">5.13. History Access Settings</a></span></dt><dt><span class="sect2"><a href="#id2937711">5.14. Clear History During Tor Toggle (optional)</a></span></dt><dt><span class="sect2"><a href="#id2979251">5.15. Block Password+Form saving during Tor/Non-Tor</a></span></dt><dt><span class="sect2"><a href="#id2979312">5.16. Block Tor disk cache and clear all cache on Tor Toggle</a></span></dt><dt><span class="sect2"><a href="#id2979362">5.17. Block disk and memory cache during Tor</a></span></dt><dt><span class="sect2"><a href="#id2979414">5.18. Clear Cookies on Tor Toggle</a></span></dt><dt><span class="sect2"><a href="#id2979465">5.19. Store Non-Tor cookies in a protected jar</a></span></dt><dt><span class="sect2"><a href="#id2979522">5.20. Store both Non-Tor and Tor cookies in a protected jar (dangerous)</a></span></dt><dt><span class="sect2"><a href="#id2979560">5.21. Manage My Own Cookies (dangerous)</a></span></dt><dt><span class="sect2"><a href="#id2979576">5.22. Disable DOM Storage during Tor usage (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2979679">5.23. Clear HTTP Auth on Tor Toggle (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2979717">5.24. Clear cookies on Tor/Non-Tor shutdown</a></span></dt><dt><span class="sect2"><a href="#id2979772">5.25. Reload cookie jar/clear cookies on Firefox crash</a></span></dt><dt><span class="sect2"><a href="#id2979847">5.26. On crash recovery or session restored startup, restore via: Tor, Non-Tor</a></span></dt><dt><span class="sect2"><a href="#id2979919">5.27. On normal startup, set state to: Tor, Non-Tor, Shutdown State</a></span></dt><dt><span class="sect2"><a href="#id2979978">5.28. Prevent session store from saving Non-Tor/Tor-loaded tabs</a></span></dt><dt><span class="sect2"><a href="#id2980042">5.29. Set user agent during Tor usage (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2980217">5.30. Spoof US English Browser</a></span></dt><dt><span class="sect2"><a href="#id2980310">5.31. Don't send referrer during Tor Usage</a></span></dt><dt><span class="sect2"><a href="#id2980350">5.32. Strip platform and language off of Google Search Box queries</a></span></dt><dt><span class="sect2"><a href="#id2980391">5.33. Automatically use an alternate search engine when presented with a

-Google Captcha</a></span></dt><dt><span class="sect2"><a href="#id2980471">5.34. Store SSL/CA Certs in separate jars for Tor/Non-Tor (recommended)</a></span></dt></dl></dd><dt><span class="sect1"><a href="#FirefoxBugs">6. Relevant Firefox Bugs</a></span></dt><dd><dl><dt><span class="sect2"><a href="#FirefoxSecurity">6.1. Bugs impacting security</a></span></dt><dt><span class="sect2"><a href="#FirefoxWishlist">6.2. Bugs blocking functionality</a></span></dt><dt><span class="sect2"><a href="#FirefoxMiscBugs">6.3. Low Priority Bugs</a></span></dt></dl></dd><dt><span class="sect1"><a href="#TestPlan">7. Testing</a></span></dt><dd><dl><dt><span class="sect2"><a href="#SingleStateTesting">7.1. Single state testing</a></span></dt><dt><span class="sect2"><a href="#id2981478">7.2. Multi-state testing</a></span></dt><dt><span class="sect2"><a href="#HackTorbutton">7.3. Active testing (aka How to Hack Torbutton)</a></span></dt></dl></dd></dl></div><div class="sect1" title="1. Introduction"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2945584"></a>1. Introduction</h2></div></div></div><p>

+<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Torbutton Design Documentation</title><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /></head><body><div class="article" title="Torbutton Design Documentation"><div class="titlepage"><div><div><h2 class="title"><a id="design"></a>Torbutton Design Documentation</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Mike</span> <span class="surname">Perry</span></h3><div class="affiliation"><div class="address"><p><code class="email">&lt;<a class="email" href="mailto:mikeperry.fscked/org">mikeperry.fscked/org</a>&gt;</code></p></div></div></div></div><div><p class="pubdate">Jun 28 2010</p></div></div><hr /></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="#id2910402">1. Introduction</a></span></dt><dd><dl><dt><span class="sect2"><a href="#adversary">1.1. Adversary Model</a></span></dt><dt><span class="sect2"><a href="#requirements">1.2. Torbutton Requirements</a></span></dt><dt><span class="sect2"><a href="#layout">1.3. Extension Layout</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2907285">2. Components</a></span></dt><dd><dl><dt><span class="sect2"><a href="#id2927418">2.1. Hooked Components</a></span></dt><dt><span class="sect2"><a href="#id2922900">2.2. New Components</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2907191">3. Chrome</a></span></dt><dd><dl><dt><span class="sect2"><a href="#browseroverlay">3.1. Browser Overlay - torbutton.xul</a></span></dt><dt><span class="sect2"><a href="#id2922887">3.2. Preferences Window - preferences.xul</a></span></dt><dt><span class="sect2"><a href="#id2922834">3.3. Other Windows</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2917336">4. Toggle Code Path</a></span></dt><dd><dl><dt><span class="sect2"><a href="#id2934128">4.1. Button Click</a></span></dt><dt><span class="sect2"><a href="#id2915503">4.2. Proxy Update</a></span></dt><dt><span class="sect2"><a href="#id2931338">4.3. Settings Update</a></span></dt></dl></dd><dt><span class="sect1"><a href="#id2898010">5. Description of Options</a></span></dt><dd><dl><dt><span class="sect2"><a href="#id2910532">5.1. Test Settings</a></span></dt><dt><span class="sect2"><a href="#plugins">5.2. Disable plugins on Tor Usage (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2917719">5.3. Isolate Dynamic Content to Tor State (crucial)</a></span></dt><dt><span class="sect2"><a href="#jshooks">5.4. Hook Dangerous Javascript</a></span></dt><dt><span class="sect2"><a href="#id2897638">5.5. Resize windows to multiples of 50px during Tor usage (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2924640">5.6. Disable Updates During Tor</a></span></dt><dt><span class="sect2"><a href="#id2892217">5.7. Redirect Torbutton Updates Via Tor (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2892261">5.8. Disable Search Suggestions during Tor (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2892300">5.9. Disable livemarks updates during Tor usage (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2892371">5.10. Block Tor/Non-Tor access to network from file:// urls (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2892443">5.11. Close all Tor/Non-Tor tabs and windows on toggle (optional)</a></span></dt><dt><span class="sect2"><a href="#id2892524">5.12. Isolate Access to History navigation to Tor state (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2892609">5.13. History Access Settings</a></span></dt><dt><span class="sect2"><a href="#id2892721">5.14. Clear History During Tor Toggle (optional)</a></span></dt><dt><span class="sect2"><a href="#id2934267">5.15. Block Password+Form saving during Tor/Non-Tor</a></span></dt><dt><span class="sect2"><a href="#id2934328">5.16. Block Tor disk cache and clear all cache on Tor Toggle</a></span></dt><dt><span class="sect2"><a href="#id2934378">5.17. Block disk and memory cache during Tor</a></span></dt><dt><span class="sect2"><a href="#id2934430">5.18. Clear Cookies on Tor Toggle</a></span></dt><dt><span class="sect2"><a href="#id2934481">5.19. Store Non-Tor cookies in a protected jar</a></span></dt><dt><span class="sect2"><a href="#id2934538">5.20. Store both Non-Tor and Tor cookies in a protected jar (dangerous)</a></span></dt><dt><span class="sect2"><a href="#id2934577">5.21. Manage My Own Cookies (dangerous)</a></span></dt><dt><span class="sect2"><a href="#id2934592">5.22. Disable DOM Storage during Tor usage (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2934696">5.23. Clear HTTP Auth on Tor Toggle (recommended)</a></span></dt><dt><span class="sect2"><a href="#id2934733">5.24. Clear cookies on Tor/Non-Tor shutdown</a></span></dt><dt><span class="sect2"><a href="#id2934788">5.25. Reload cookie jar/clear cookies on Firefox crash</a></span></dt><dt><span class="sect2"><a href="#id2934863">5.26. On crash recovery or session restored startup, restore via: Tor, Non-Tor</a></span></dt><dt><span class="sect2"><a href="#id2934935">5.27. On normal startup, set state to: Tor, Non-Tor, Shutdown State</a></span></dt><dt><span class="sect2"><a href="#id2934994">5.28. Prevent session store from saving Non-Tor/Tor-loaded tabs</a></span></dt><dt><span class="sect2"><a href="#id2935059">5.29. Set user agent during Tor usage (crucial)</a></span></dt><dt><span class="sect2"><a href="#id2935233">5.30. Spoof US English Browser</a></span></dt><dt><span class="sect2"><a href="#id2935326">5.31. Don't send referrer during Tor Usage</a></span></dt><dt><span class="sect2"><a href="#id2935366">5.32. Strip platform and language off of Google Search Box queries</a></span></dt><dt><span class="sect2"><a href="#id2935407">5.33. Automatically use an alternate search engine when presented with a

+Google Captcha</a></span></dt><dt><span class="sect2"><a href="#id2935487">5.34. Store SSL/CA Certs in separate jars for Tor/Non-Tor (recommended)</a></span></dt></dl></dd><dt><span class="sect1"><a href="#FirefoxBugs">6. Relevant Firefox Bugs</a></span></dt><dd><dl><dt><span class="sect2"><a href="#FirefoxSecurity">6.1. Bugs impacting security</a></span></dt><dt><span class="sect2"><a href="#FirefoxWishlist">6.2. Bugs blocking functionality</a></span></dt><dt><span class="sect2"><a href="#FirefoxMiscBugs">6.3. Low Priority Bugs</a></span></dt></dl></dd><dt><span class="sect1"><a href="#TestPlan">7. Testing</a></span></dt><dd><dl><dt><span class="sect2"><a href="#SingleStateTesting">7.1. Single state testing</a></span></dt><dt><span class="sect2"><a href="#id2936532">7.2. Multi-state testing</a></span></dt><dt><span class="sect2"><a href="#HackTorbutton">7.3. Active testing (aka How to Hack Torbutton)</a></span></dt></dl></dd></dl></div><div class="sect1" title="1. Introduction"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2910402"></a>1. Introduction</h2></div></div></div><p>

 This document describes the goals, operation, and testing procedures of the

 Torbutton Firefox extension. It is current as of Torbutton 1.2.5.

@@ -232,13 +232,13 @@ obsolete and deprecated interfaces and has proved to be less than

 stable.</p><p>'Chrome' is a combination of XML and Javascript used to describe a window.

 Extensions are allowed to create 'overlays' that are 'bound' to existing XML

 window definitions, or they can create their own windows. The DTD for this XML

-is called <a class="ulink" href="http://developer.mozilla.org/en/docs/XUL_Reference" target="_top">XUL</a>.</p></div></div><div class="sect1" title="2. Components"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2976187"></a>2. Components</h2></div></div></div><p>

+is called <a class="ulink" href="http://developer.mozilla.org/en/docs/XUL_Reference" target="_top">XUL</a>.</p></div></div><div class="sect1" title="2. Components"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2907285"></a>2. Components</h2></div></div></div><p>

 Torbutton installs components for two purposes: hooking existing components to

 reimplement their interfaces; and creating new components that provide

 services to other pieces of the extension.

-  </p><div class="sect2" title="2.1. Hooked Components"><div class="titlepage"><div><div><h3 class="title"><a id="id2969623"></a>2.1. Hooked Components</h3></div></div></div><p>Torbutton makes extensive use of Contract ID hooking, and implements some

+  </p><div class="sect2" title="2.1. Hooked Components"><div class="titlepage"><div><div><h3 class="title"><a id="id2927418"></a>2.1. Hooked Components</h3></div></div></div><p>Torbutton makes extensive use of Contract ID hooking, and implements some

 of its own standalone components as well.  Let's discuss the hooked components

 first.</p><div class="sect3" title="@mozilla.org/browser/sessionstore;1 - components/nsSessionStore36.js"><div class="titlepage"><div><div><h4 class="title"><a id="sessionstore"></a><a class="ulink" href="http://developer.mozilla.org/en/docs/nsISessionStore" target="_top">@mozilla.org/browser/sessionstore;1</a> -

 <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/nsSessionStore36.js" target="_top">components/nsSessionStore36.js</a></h4></div></div></div><p>These components address the <a class="link" href="#disk">Disk Avoidance</a>

@@ -267,7 +267,7 @@ do not obey proxy settings, they can be manipulated to automatically connect

 back to arbitrary servers outside of Tor with no user intervention. Fixing

 this issue helps to satisfy Torbutton's <a class="link" href="#proxy">Proxy

 Obedience</a> Requirement.

- </p></div><div class="sect3" title="@mozilla.org/browser/sessionstartup;1 - components/crash-observer.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2962061"></a><a class="ulink" href="http://lxr.mozilla.org/seamonkey/source/browser/components/sessionstore/src/nsSessionStartup.js" target="_top">@mozilla.org/browser/sessionstartup;1</a> -

+ </p></div><div class="sect3" title="@mozilla.org/browser/sessionstartup;1 - components/crash-observer.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2924906"></a><a class="ulink" href="http://lxr.mozilla.org/seamonkey/source/browser/components/sessionstore/src/nsSessionStartup.js" target="_top">@mozilla.org/browser/sessionstartup;1</a> -

     <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/crash-observer.js" target="_top">components/crash-observer.js</a></h4></div></div></div><p>This component wraps the Firefox Session Startup component that is in

 charge of <a class="ulink" href="http://developer.mozilla.org/en/docs/Session_store_API" target="_top">restoring saved

 sessions</a>. The wrapper's only job is to intercept the

@@ -281,7 +281,7 @@ includes setting the Tor state to the one the user selected for crash recovery

 in the preferences window (<span class="command"><strong>extensions.torbutton.restore_tor</strong></span>), and

 restoring cookies for the corresponding cookie jar, if it exists.</p><p>By performing this notification, this component assists in the 

 <a class="link" href="#proxy">Proxy Obedience</a>, and <a class="link" href="#isolation">Network Isolation</a> requirements.

-</p></div><div class="sect3" title="@mozilla.org/browser/global-history;2 - components/ignore-history.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2970544"></a><a class="ulink" href="http://www.oxymoronical.com/experiments/xpcomref/applications/Firefox/3.5/components/%40mozilla.org/browser/global-history;2" target="_top">@mozilla.org/browser/global-history;2</a>

+</p></div><div class="sect3" title="@mozilla.org/browser/global-history;2 - components/ignore-history.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2921641"></a><a class="ulink" href="http://www.oxymoronical.com/experiments/xpcomref/applications/Firefox/3.5/components/%40mozilla.org/browser/global-history;2" target="_top">@mozilla.org/browser/global-history;2</a>

 - <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/ignore-history.js" target="_top">components/ignore-history.js</a></h4></div></div></div><p>This component was contributed by <a class="ulink" href="http://www.collinjackson.com/" target="_top">Collin Jackson</a> as a method for defeating

 CSS and Javascript-based methods of history disclosure. The global-history

 component is what is used by Firefox to determine if a link was visited or not

@@ -306,9 +306,9 @@ firing in the event the browser starts in Tor mode.

 This component helps satisfy the <a class="link" href="#isolation">Network

 Isolation</a> and <a class="link" href="#setpreservation">Anonymity Set

 Preservation</a> requirements.

-</p></div></div><div class="sect2" title="2.2. New Components"><div class="titlepage"><div><div><h3 class="title"><a id="id2952263"></a>2.2. New Components</h3></div></div></div><p>Torbutton creates four new components that are used throughout the

+</p></div></div><div class="sect2" title="2.2. New Components"><div class="titlepage"><div><div><h3 class="title"><a id="id2922900"></a>2.2. New Components</h3></div></div></div><p>Torbutton creates four new components that are used throughout the

 extension. These components do not hook any interfaces, nor are they used

-anywhere besides Torbutton itself.</p><div class="sect3" title="@torproject.org/cookie-jar-selector;2 - components/cookie-jar-selector.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2952530"></a><a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/cookie-jar-selector.js" target="_top">@torproject.org/cookie-jar-selector;2

+anywhere besides Torbutton itself.</p><div class="sect3" title="@torproject.org/cookie-jar-selector;2 - components/cookie-jar-selector.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2909775"></a><a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/cookie-jar-selector.js" target="_top">@torproject.org/cookie-jar-selector;2

 - components/cookie-jar-selector.js</a></h4></div></div></div><p>The cookie jar selector (also based on code from <a class="ulink" href="http://www.collinjackson.com/" target="_top">Collin

 Jackson</a>) is used by the Torbutton chrome to switch between

 Tor and Non-Tor cookies. Its operations are simple: sync cookies to disk, then

@@ -317,7 +317,7 @@ move the current cookies.txt file to the appropriate backup location

 into place.</p><p>

 This component helps to address the <a class="link" href="#state">State

 Isolation</a> requirement of Torbutton.

-</p></div><div class="sect3" title="@torproject.org/torbutton-logger;1 - components/torbutton-logger.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2965661"></a><a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/torbutton-logger.js" target="_top">@torproject.org/torbutton-logger;1

+</p></div><div class="sect3" title="@torproject.org/torbutton-logger;1 - components/torbutton-logger.js"><div class="titlepage"><div><div><h4 class="title"><a id="id2906606"></a><a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/torbutton-logger.js" target="_top">@torproject.org/torbutton-logger;1

 - components/torbutton-logger.js</a></h4></div></div></div><p>The torbutton logger component allows on-the-fly redirection of torbutton

 logging messages to either Firefox stderr

 (<span class="command"><strong>extensions.torbutton.logmethod=0</strong></span>), the Javascript error console

@@ -369,7 +369,7 @@ reason are not passed to the Firefox content policy itself (see Firefox Bugs

 </p><p>

 This helps to fulfill both the <a class="link" href="#setpreservation">Anonymity Set Preservation</a> and the <a class="link" href="#undiscoverability">Tor Undiscoverability</a> requirements of

-Torbutton.</p></div></div></div><div class="sect1" title="3. Chrome"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2962049"></a>3. Chrome</h2></div></div></div><p>The chrome is where all the torbutton graphical elements and windows are

+Torbutton.</p></div></div></div><div class="sect1" title="3. Chrome"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2907191"></a>3. Chrome</h2></div></div></div><p>The chrome is where all the torbutton graphical elements and windows are

 located. Each window is described as an <a class="ulink" href="http://developer.mozilla.org/en/docs/XUL_Reference" target="_top">XML file</a>, with zero or more Javascript

 files attached. The scope of these Javascript files is their containing

 window.</p><div class="sect2" title="3.1. Browser Overlay - torbutton.xul"><div class="titlepage"><div><div><h3 class="title"><a id="browseroverlay"></a>3.1. Browser Overlay - <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/chrome/content/torbutton.xul" target="_top">torbutton.xul</a></h3></div></div></div><p>The browser overlay, torbutton.xul, defines the toolbar button, the status

@@ -496,9 +496,9 @@ enabled. This helps Torbutton fulfill its <a class="link" href="#disk">Disk

 Avoidance</a> and <a class="link" href="#state">State Separation</a>

 requirements.

-   </p></li></ol></div></div><div class="sect2" title="3.2. Preferences Window - preferences.xul"><div class="titlepage"><div><div><h3 class="title"><a id="id2941767"></a>3.2. Preferences Window - <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/chrome/content/preferences.xul" target="_top">preferences.xul</a></h3></div></div></div><p>The preferences window of course lays out the Torbutton preferences, with

-handlers located in <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/chrome/content/preferences.js" target="_top">chrome/content/preferences.js</a>.</p></div><div class="sect2" title="3.3. Other Windows"><div class="titlepage"><div><div><h3 class="title"><a id="id2976170"></a>3.3. Other Windows</h3></div></div></div><p>There are additional windows that describe popups for right clicking on

-the status bar, the toolbutton, and the about page.</p></div></div><div class="sect1" title="4. Toggle Code Path"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2977751"></a>4. Toggle Code Path</h2></div></div></div><p>

+   </p></li></ol></div></div><div class="sect2" title="3.2. Preferences Window - preferences.xul"><div class="titlepage"><div><div><h3 class="title"><a id="id2922887"></a>3.2. Preferences Window - <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/chrome/content/preferences.xul" target="_top">preferences.xul</a></h3></div></div></div><p>The preferences window of course lays out the Torbutton preferences, with

+handlers located in <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/chrome/content/preferences.js" target="_top">chrome/content/preferences.js</a>.</p></div><div class="sect2" title="3.3. Other Windows"><div class="titlepage"><div><div><h3 class="title"><a id="id2922834"></a>3.3. Other Windows</h3></div></div></div><p>There are additional windows that describe popups for right clicking on

+the status bar, the toolbutton, and the about page.</p></div></div><div class="sect1" title="4. Toggle Code Path"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2917336"></a>4. Toggle Code Path</h2></div></div></div><p>

 The act of toggling is connected to <code class="function">torbutton_toggle()</code>

 via the <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/chrome/content/torbutton.xul" target="_top">torbutton.xul</a>

@@ -519,7 +519,7 @@ conditions and leakage, especially with <a class="ulink" href="https://bugzilla.

 409737</a> unfixed. The content policy does not allow any network activity

 whatsoever during this three stage transition.

- </p><div class="sect2" title="4.1. Button Click"><div class="titlepage"><div><div><h3 class="title"><a id="id2944154"></a>4.1. Button Click</h3></div></div></div><p>

+ </p><div class="sect2" title="4.1. Button Click"><div class="titlepage"><div><div><h3 class="title"><a id="id2934128"></a>4.1. Button Click</h3></div></div></div><p>

 This is the first step in the toggling process. When the user clicks the

 toggle button or the toolbar, <code class="function">torbutton_toggle()</code> is

@@ -532,7 +532,7 @@ observer</a>

 <span class="command"><strong>torbutton_unique_pref_observer</strong></span> to perform the rest of the

 toggle.

-  </p></div><div class="sect2" title="4.2. Proxy Update"><div class="titlepage"><div><div><h3 class="title"><a id="id2978704"></a>4.2. Proxy Update</h3></div></div></div><p>

+  </p></div><div class="sect2" title="4.2. Proxy Update"><div class="titlepage"><div><div><h3 class="title"><a id="id2915503"></a>4.2. Proxy Update</h3></div></div></div><p>

 When Torbutton receives any proxy change notifications via its

 <span class="command"><strong>torbutton_unique_pref_observer</strong></span>, it calls

@@ -547,7 +547,7 @@ value. This is decoupled from the button click functionalty via the pref

 observer so that other addons (such as SwitchProxy) can switch the proxy

 settings between multiple proxies.

-  </p></div><div class="sect2" title="4.3. Settings Update"><div class="titlepage"><div><div><h3 class="title"><a id="id2945348"></a>4.3. Settings Update</h3></div></div></div><p>

+  </p></div><div class="sect2" title="4.3. Settings Update"><div class="titlepage"><div><div><h3 class="title"><a id="id2931338"></a>4.3. Settings Update</h3></div></div></div><p>

 The next stage is also handled by

 <code class="function">torbutton_update_status()</code>. This function sets scores of

@@ -558,10 +558,10 @@ end of its work, it sets

 <span class="command"><strong>extensions.torbutton.settings_applied</strong></span>, which signifies the

 completion of the toggle operation to the <a class="link" href="#contentpolicy" title="@torproject.org/cssblocker;1 - components/cssblocker.js">content policy</a>.

-  </p></div></div><div class="sect1" title="5. Description of Options"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2966553"></a>5. Description of Options</h2></div></div></div><p>This section provides a detailed description of Torbutton's options. Each

+  </p></div></div><div class="sect1" title="5. Description of Options"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id2898010"></a>5. Description of Options</h2></div></div></div><p>This section provides a detailed description of Torbutton's options. Each

 option is presented as the string from the preferences window, a summary, the

 preferences it touches, and the effect this has on the components, chrome, and

-browser properties.</p><div class="sect2" title="5.1. Test Settings"><div class="titlepage"><div><div><h3 class="title"><a id="id2948284"></a>5.1. Test Settings</h3></div></div></div><p>

+browser properties.</p><div class="sect2" title="5.1. Test Settings"><div class="titlepage"><div><div><h3 class="title"><a id="id2910532"></a>5.1. Test Settings</h3></div></div></div><p>

 This button under the Proxy Settings tab provides a way to verify that the 

 proxy settings are correct, and actually do route through the Tor network. It

 performs this check by issuing an <a class="ulink" href="http://developer.mozilla.org/en/docs/XMLHttpRequest" target="_top">XMLHTTPRequest</a>

@@ -620,7 +620,7 @@ all this and the plugin managed to find some way to load.

 Since most plugins completely ignore browser proxy settings, the actions

 performed by this setting are crucial to satisfying the <a class="link" href="#proxy">Proxy Obedience</a> requirement.

- </p></div><div class="sect2" title="5.3. Isolate Dynamic Content to Tor State (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2965289"></a>5.3. Isolate Dynamic Content to Tor State (crucial)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.isolate_content</strong></span></p><p>Enabling this preference is what enables the <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/cssblocker.js" target="_top">@torproject.org/cssblocker;1</a> content policy

+ </p></div><div class="sect2" title="5.3. Isolate Dynamic Content to Tor State (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2917719"></a>5.3. Isolate Dynamic Content to Tor State (crucial)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.isolate_content</strong></span></p><p>Enabling this preference is what enables the <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/cssblocker.js" target="_top">@torproject.org/cssblocker;1</a> content policy

 mentioned above, and causes it to block content load attempts in pages an

 opposite Tor state from the current state. Freshly loaded <a class="ulink" href="https://developer.mozilla.org/en/XUL/tabbrowser" target="_top">browser

 tabs</a> are tagged

@@ -672,7 +672,7 @@ We are still looking for a workaround as of Torbutton 1.2.5.

-</p></div><div class="sect2" title="5.5. Resize windows to multiples of 50px during Tor usage (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2964952"></a>5.5. Resize windows to multiples of 50px during Tor usage (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.resize_windows</strong></span></p><p>

+</p></div><div class="sect2" title="5.5. Resize windows to multiples of 50px during Tor usage (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2897638"></a>5.5. Resize windows to multiples of 50px during Tor usage (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.resize_windows</strong></span></p><p>

 This option drastically cuts down on the number of distinct anonymity sets

 that divide the Tor web userbase. Without this setting, the dimensions for a

@@ -707,7 +707,7 @@ infer toolbar size/presence by the distance to the nearest 50 pixel roundoff).

 </p><p>

 This setting helps to meet the <a class="link" href="#setpreservation">Anonymity Set Preservation</a> requirements.

-</p></div><div class="sect2" title="5.6. Disable Updates During Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2977086"></a>5.6. Disable Updates During Tor</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.no_updates</strong></span></p><p>This setting causes Torbutton to disable the four <a class="ulink" href="http://wiki.mozilla.org/Update:Users/Checking_For_Updates#Preference_Controls_and_State" target="_top">Firefox

+</p></div><div class="sect2" title="5.6. Disable Updates During Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2924640"></a>5.6. Disable Updates During Tor</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.no_updates</strong></span></p><p>This setting causes Torbutton to disable the four <a class="ulink" href="http://wiki.mozilla.org/Update:Users/Checking_For_Updates#Preference_Controls_and_State" target="_top">Firefox

 update settings</a> during Tor

   usage: <span class="command"><strong>extensions.update.enabled</strong></span>,

 <span class="command"><strong>app.update.enabled</strong></span>,

@@ -717,7 +717,7 @@ update settings</a> during Tor

   checking for search plugin updates while Tor is enabled.

   </p><p>

 This setting satisfies the <a class="link" href="#updates">Update Safety</a> requirement.

-</p></div><div class="sect2" title="5.7. Redirect Torbutton Updates Via Tor (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2937206"></a>5.7. Redirect Torbutton Updates Via Tor (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.update_torbutton_via_tor</strong></span></p><p>This setting causes Torbutton to install an

+</p></div><div class="sect2" title="5.7. Redirect Torbutton Updates Via Tor (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2892217"></a>5.7. Redirect Torbutton Updates Via Tor (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.update_torbutton_via_tor</strong></span></p><p>This setting causes Torbutton to install an

 <a class="ulink" href="https://developer.mozilla.org/en/nsIProtocolProxyFilter" target="_top">nsIProtocolProxyFilter</a>

 in order to redirect all version update checks and Torbutton update downloads

@@ -726,7 +726,7 @@ concerns about data retention done by <a class="ulink" href="https://www.addons.

 help censored users meet the <a class="link" href="#undiscoverability">Tor

 Undiscoverability</a> requirement.

-  </p></div><div class="sect2" title="5.8. Disable Search Suggestions during Tor (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2937250"></a>5.8. Disable Search Suggestions during Tor (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.no_search</strong></span></p><p>

+  </p></div><div class="sect2" title="5.8. Disable Search Suggestions during Tor (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2892261"></a>5.8. Disable Search Suggestions during Tor (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.no_search</strong></span></p><p>

 This setting causes Torbutton to disable <a class="ulink" href="http://kb.mozillazine.org/Browser.search.suggest.enabled" target="_top"><span class="command"><strong>browser.search.suggest.enabled</strong></span></a>

 during Tor usage.

 This governs if you get Google search suggestions during Tor

@@ -737,7 +737,7 @@ this is recommended to be disabled.

 While this setting doesn't satisfy any Torbutton requirements, the fact that

 cookies are transmitted for partially typed queries does not seem desirable

 for Tor usage.

-</p></div><div class="sect2" title="5.9. Disable livemarks updates during Tor usage (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2937289"></a>5.9. Disable livemarks updates during Tor usage (recommended)</h3></div></div></div><p>Option:

+</p></div><div class="sect2" title="5.9. Disable livemarks updates during Tor usage (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2892300"></a>5.9. Disable livemarks updates during Tor usage (recommended)</h3></div></div></div><p>Option:

    </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.disable_livemarks</strong></span></td></tr></table><p>

   </p><p>

 This option causes Torbutton to prevent Firefox from loading <a class="ulink" href="http://www.mozilla.com/firefox/livebookmarks.html" target="_top">Livemarks</a> during

@@ -751,7 +751,7 @@ service</a> when Tor is enabled.

 This helps satisfy the <a class="link" href="#isolation">Network

 Isolation</a> and <a class="link" href="#setpreservation">Anonymity Set

 Preservation</a> requirements.

-</p></div><div class="sect2" title="5.10. Block Tor/Non-Tor access to network from file:// urls (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2937361"></a>5.10. Block Tor/Non-Tor access to network from file:// urls (recommended)</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.10. Block Tor/Non-Tor access to network from file:// urls (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2892371"></a>5.10. Block Tor/Non-Tor access to network from file:// urls (recommended)</h3></div></div></div><p>Options:

    </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.block_tor_file_net</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.block_nontor_file_net</strong></span></td></tr></table><p>

   </p><p>

@@ -771,7 +771,7 @@ Isolation</a> requirement, by preventing file urls from executing network

 operations in opposite Tor states. Also, allowing pages to submit arbitrary

 files to arbitrary sites just generally seems like a bad idea.

-</p></div><div class="sect2" title="5.11. Close all Tor/Non-Tor tabs and windows on toggle (optional)"><div class="titlepage"><div><div><h3 class="title"><a id="id2937433"></a>5.11. Close all Tor/Non-Tor tabs and windows on toggle (optional)</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.11. Close all Tor/Non-Tor tabs and windows on toggle (optional)"><div class="titlepage"><div><div><h3 class="title"><a id="id2892443"></a>5.11. Close all Tor/Non-Tor tabs and windows on toggle (optional)</h3></div></div></div><p>Options:

    </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.close_nontor</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.close_tor</strong></span></td></tr></table><p>

   </p><p>

@@ -795,7 +795,7 @@ out longer than necessary.

 While this setting doesn't satisfy any Torbutton requirements, the fact that

 cookies are transmitted for partially typed queries does not seem desirable

 for Tor usage.

-</p></div><div class="sect2" title="5.12. Isolate Access to History navigation to Tor state (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2937514"></a>5.12. Isolate Access to History navigation to Tor state (crucial)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.block_js_history</strong></span></p><p>

+</p></div><div class="sect2" title="5.12. Isolate Access to History navigation to Tor state (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2892524"></a>5.12. Isolate Access to History navigation to Tor state (crucial)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.block_js_history</strong></span></p><p>

 This setting determines if Torbutton installs an <a class="ulink" href="http://www.oxymoronical.com/experiments/apidocs/interface/nsISHistoryListener" target="_top">nsISHistoryListener</a>

 attached to the <a class="ulink" href="http://www.oxymoronical.com/experiments/apidocs/interface/nsISHistory" target="_top">sessionHistory</a> of 

 of each browser's <a class="ulink" href="https://developer.mozilla.org/en/XUL%3aProperty%3awebNavigation" target="_top">webNavigatator</a>.

@@ -823,7 +823,7 @@ This setting helps to fulfill Torbutton's <a class="link" href="#state">State

 Separation</a> and (until Bug 409737 is fixed) <a class="link" href="#isolation">Network Isolation</a>

 requirements.

-   </p></div><div class="sect2" title="5.13. History Access Settings"><div class="titlepage"><div><div><h3 class="title"><a id="id2937598"></a>5.13. History Access Settings</h3></div></div></div><p>Options:

+   </p></div><div class="sect2" title="5.13. History Access Settings"><div class="titlepage"><div><div><h3 class="title"><a id="id2892609"></a>5.13. History Access Settings</h3></div></div></div><p>Options:

   </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.block_thread</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.block_nthread</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.block_thwrite</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.block_nthwrite</strong></span></td></tr></table><p>

   </p><p>These four settings govern the behavior of the <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/ignore-history.js" target="_top">components/ignore-history.js</a>

 history blocker component mentioned above. By hooking the browser's view of

@@ -838,12 +838,12 @@ Database</a> and the older Firefox 2 mechanisms.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> and <a class="link" href="#disk">Disk Avoidance</a> requirements.

-</p></div><div class="sect2" title="5.14. Clear History During Tor Toggle (optional)"><div class="titlepage"><div><div><h3 class="title"><a id="id2937711"></a>5.14. Clear History During Tor Toggle (optional)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_history</strong></span></p><p>This setting governs if Torbutton calls

+</p></div><div class="sect2" title="5.14. Clear History During Tor Toggle (optional)"><div class="titlepage"><div><div><h3 class="title"><a id="id2892721"></a>5.14. Clear History During Tor Toggle (optional)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_history</strong></span></p><p>This setting governs if Torbutton calls

 <a class="ulink" href="https://developer.mozilla.org/en/nsIBrowserHistory#removeAllPages.28.29" target="_top">nsIBrowserHistory.removeAllPages</a>

 and <a class="ulink" href="http://www.oxymoronical.com/experiments/apidocs/interface/nsISHistory" target="_top">nsISHistory.PurgeHistory</a>

 for each tab on Tor toggle.</p><p>

 This setting is an optional way to help satisfy the <a class="link" href="#state">State Separation</a> requirement.

-</p></div><div class="sect2" title="5.15. Block Password+Form saving during Tor/Non-Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2979251"></a>5.15. Block Password+Form saving during Tor/Non-Tor</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.15. Block Password+Form saving during Tor/Non-Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2934267"></a>5.15. Block Password+Form saving during Tor/Non-Tor</h3></div></div></div><p>Options:

   </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.block_tforms</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.block_ntforms</strong></span></td></tr></table><p>

   </p><p>These settings govern if Torbutton disables

 <span class="command"><strong>browser.formfill.enable</strong></span>

@@ -852,19 +852,19 @@ Since form fields can be read at any time by Javascript, this setting is a lot

 more important than it seems.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> and <a class="link" href="#disk">Disk Avoidance</a> requirements.

-</p></div><div class="sect2" title="5.16. Block Tor disk cache and clear all cache on Tor Toggle"><div class="titlepage"><div><div><h3 class="title"><a id="id2979312"></a>5.16. Block Tor disk cache and clear all cache on Tor Toggle</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_cache</strong></span>

+</p></div><div class="sect2" title="5.16. Block Tor disk cache and clear all cache on Tor Toggle"><div class="titlepage"><div><div><h3 class="title"><a id="id2934328"></a>5.16. Block Tor disk cache and clear all cache on Tor Toggle</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_cache</strong></span>

   </p><p>This option causes Torbutton to call <a class="ulink" href="https://developer.mozilla.org/en/nsICacheService#evictEntries.28.29" target="_top">nsICacheService.evictEntries(0)</a>

 on Tor toggle to remove all entries from the cache. In addition, this setting

 causes Torbutton to set <a class="ulink" href="http://kb.mozillazine.org/Browser.cache.disk.enable" target="_top">browser.cache.disk.enable</a> to false.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> and <a class="link" href="#disk">Disk Avoidance</a> requirements.

-</p></div><div class="sect2" title="5.17. Block disk and memory cache during Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2979362"></a>5.17. Block disk and memory cache during Tor</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.block_cache</strong></span></p><p>This setting

+</p></div><div class="sect2" title="5.17. Block disk and memory cache during Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2934378"></a>5.17. Block disk and memory cache during Tor</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.block_cache</strong></span></p><p>This setting

 causes Torbutton to set <a class="ulink" href="http://kb.mozillazine.org/Browser.cache.memory.enable" target="_top">browser.cache.memory.enable</a>,

 <a class="ulink" href="http://kb.mozillazine.org/Browser.cache.disk.enable" target="_top">browser.cache.disk.enable</a> and

 <a class="ulink" href="http://kb.mozillazine.org/Network.http.use-cache" target="_top">network.http.use-cache</a> to false during tor usage.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> and <a class="link" href="#disk">Disk Avoidance</a> requirements.

-</p></div><div class="sect2" title="5.18. Clear Cookies on Tor Toggle"><div class="titlepage"><div><div><h3 class="title"><a id="id2979414"></a>5.18. Clear Cookies on Tor Toggle</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_cookies</strong></span>

+</p></div><div class="sect2" title="5.18. Clear Cookies on Tor Toggle"><div class="titlepage"><div><div><h3 class="title"><a id="id2934430"></a>5.18. Clear Cookies on Tor Toggle</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_cookies</strong></span>

   </p><p>

 This setting causes Torbutton to call <a class="ulink" href="https://developer.mozilla.org/en/nsICookieManager#removeAll.28.29" target="_top">nsICookieManager.removeAll()</a> on

@@ -874,7 +874,7 @@ which prevents them from being written to disk.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> and <a class="link" href="#disk">Disk Avoidance</a> requirements.

-</p></div><div class="sect2" title="5.19. Store Non-Tor cookies in a protected jar"><div class="titlepage"><div><div><h3 class="title"><a id="id2979465"></a>5.19. Store Non-Tor cookies in a protected jar</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.cookie_jars</strong></span>

+</p></div><div class="sect2" title="5.19. Store Non-Tor cookies in a protected jar"><div class="titlepage"><div><div><h3 class="title"><a id="id2934481"></a>5.19. Store Non-Tor cookies in a protected jar</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.cookie_jars</strong></span>

   </p><p>

 This setting causes Torbutton to use <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/cookie-jar-selector.js" target="_top">@torproject.org/cookie-jar-selector;2</a> to store

@@ -887,15 +887,15 @@ which prevents them from being written to disk.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> and <a class="link" href="#disk">Disk Avoidance</a> requirements.

-</p></div><div class="sect2" title="5.20. Store both Non-Tor and Tor cookies in a protected jar (dangerous)"><div class="titlepage"><div><div><h3 class="title"><a id="id2979522"></a>5.20. Store both Non-Tor and Tor cookies in a protected jar (dangerous)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.dual_cookie_jars</strong></span>

+</p></div><div class="sect2" title="5.20. Store both Non-Tor and Tor cookies in a protected jar (dangerous)"><div class="titlepage"><div><div><h3 class="title"><a id="id2934538"></a>5.20. Store both Non-Tor and Tor cookies in a protected jar (dangerous)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.dual_cookie_jars</strong></span>

   </p><p>

 This setting causes Torbutton to use <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/cookie-jar-selector.js" target="_top">@torproject.org/cookie-jar-selector;2</a> to store

 both Tor and Non-Tor cookies into protected jars.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> requirement.

-</p></div><div class="sect2" title="5.21. Manage My Own Cookies (dangerous)"><div class="titlepage"><div><div><h3 class="title"><a id="id2979560"></a>5.21. Manage My Own Cookies (dangerous)</h3></div></div></div><p>Options: None</p><p>This setting disables all Torbutton cookie handling by setting the above

-cookie prefs all to false.</p></div><div class="sect2" title="5.22. Disable DOM Storage during Tor usage (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2979576"></a>5.22. Disable DOM Storage during Tor usage (crucial)</h3></div></div></div><div class="sect2" title="5.22.1. Do not write Tor/Non-Tor cookies to disk"><div class="titlepage"><div><div><h3 class="title"><a id="id2979578"></a>5.22.1. Do not write Tor/Non-Tor cookies to disk</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.21. Manage My Own Cookies (dangerous)"><div class="titlepage"><div><div><h3 class="title"><a id="id2934577"></a>5.21. Manage My Own Cookies (dangerous)</h3></div></div></div><p>Options: None</p><p>This setting disables all Torbutton cookie handling by setting the above

+cookie prefs all to false.</p></div><div class="sect2" title="5.22. Disable DOM Storage during Tor usage (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2934592"></a>5.22. Disable DOM Storage during Tor usage (crucial)</h3></div></div></div><div class="sect2" title="5.22.1. Do not write Tor/Non-Tor cookies to disk"><div class="titlepage"><div><div><h3 class="title"><a id="id2934594"></a>5.22.1. Do not write Tor/Non-Tor cookies to disk</h3></div></div></div><p>Options:

   </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.tor_memory_jar</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.nontor_memory_jar</strong></span></td></tr></table><p>

   </p><p>

 These settings (contributed by arno) cause Torbutton to set <a class="ulink" href="http://kb.mozillazine.org/Network.cookie.lifetimePolicy" target="_top">network.cookie.lifetimePolicy</a>

@@ -915,13 +915,13 @@ usage to prevent

 <a class="ulink" href="http://developer.mozilla.org/en/docs/DOM:Storage" target="_top">DOM Storage</a> from

   being used to store persistent information across Tor states.</p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> requirement.

-</p></div><div class="sect2" title="5.23. Clear HTTP Auth on Tor Toggle (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2979679"></a>5.23. Clear HTTP Auth on Tor Toggle (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_http_auth</strong></span>

+</p></div><div class="sect2" title="5.23. Clear HTTP Auth on Tor Toggle (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2934696"></a>5.23. Clear HTTP Auth on Tor Toggle (recommended)</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.clear_http_auth</strong></span>

   </p><p>

 This setting causes Torbutton to call <a class="ulink" href="http://www.oxymoronical.com/experiments/apidocs/interface/nsIHttpAuthManager" target="_top">nsIHttpAuthManager.clearAll()</a>

 every time Tor is toggled.

 </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> requirement.

-</p></div><div class="sect2" title="5.24. Clear cookies on Tor/Non-Tor shutdown"><div class="titlepage"><div><div><h3 class="title"><a id="id2979717"></a>5.24. Clear cookies on Tor/Non-Tor shutdown</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.shutdown_method</strong></span>

+</p></div><div class="sect2" title="5.24. Clear cookies on Tor/Non-Tor shutdown"><div class="titlepage"><div><div><h3 class="title"><a id="id2934733"></a>5.24. Clear cookies on Tor/Non-Tor shutdown</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.shutdown_method</strong></span>

   </p><p> This option variable can actually take 3 values: 0, 1, and 2. 0 means no

 cookie clearing, 1 means clear only during Tor-enabled shutdown, and 2 means

 clear for both Tor and Non-Tor shutdown. When set to 1 or 2, Torbutton listens

@@ -929,7 +929,7 @@ for the <a class="ulink" href="http://developer.mozilla.org/en/docs/Observer_Not

 <code class="function">https://git.torproject.org/checkout/torbutton/master/src/components/crash-observer.js</code> and use <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/cookie-jar-selector.js" target="_top">@torproject.org/cookie-jar-selector;2</a>

 to clear out all cookies and all cookie jars upon shutdown.  </p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> requirement.

-</p></div><div class="sect2" title="5.25. Reload cookie jar/clear cookies on Firefox crash"><div class="titlepage"><div><div><h3 class="title"><a id="id2979772"></a>5.25. Reload cookie jar/clear cookies on Firefox crash</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.25. Reload cookie jar/clear cookies on Firefox crash"><div class="titlepage"><div><div><h3 class="title"><a id="id2934788"></a>5.25. Reload cookie jar/clear cookies on Firefox crash</h3></div></div></div><p>Options:

   </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.reload_crashed_jar</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.crashed</strong></span></td></tr></table><p>

   </p><p>This is no longer a user visible option, and is enabled by default. In

 the event of a crash, the Torbutton <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/crash-observer.js" target="_top">components/crash-observer.js</a> 

@@ -941,7 +941,7 @@ the chrome that listens for this update), and Torbutton will load the

   component.</p><p>

 This setting helps to satisfy the <a class="link" href="#state">State Separation</a> requirement in the event of Firefox

 crashes.

-</p></div><div class="sect2" title="5.26. On crash recovery or session restored startup, restore via: Tor, Non-Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2979847"></a>5.26. On crash recovery or session restored startup, restore via: Tor, Non-Tor</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.26. On crash recovery or session restored startup, restore via: Tor, Non-Tor"><div class="titlepage"><div><div><h3 class="title"><a id="id2934863"></a>5.26. On crash recovery or session restored startup, restore via: Tor, Non-Tor</h3></div></div></div><p>Options:

   </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.restore_tor</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.crashed</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.normal_exit</strong></span></td></tr></table><p>

   </p><p>This option works with the Torbutton <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/crash-observer.js" target="_top">crash-observer.js</a> 

   to set the Tor state after a crash is detected (via the 

@@ -957,7 +957,7 @@ setting helps to satisfy the <a class="link" href="#state">State Separation</a>

 requirement in the event of Firefox crashes by ensuring all cookies,

 settings and saved sessions are reloaded from a fixed Tor state.

-</p></div><div class="sect2" title="5.27. On normal startup, set state to: Tor, Non-Tor, Shutdown State"><div class="titlepage"><div><div><h3 class="title"><a id="id2979919"></a>5.27. On normal startup, set state to: Tor, Non-Tor, Shutdown State</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.27. On normal startup, set state to: Tor, Non-Tor, Shutdown State"><div class="titlepage"><div><div><h3 class="title"><a id="id2934935"></a>5.27. On normal startup, set state to: Tor, Non-Tor, Shutdown State</h3></div></div></div><p>Options:

   </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.startup_state</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.noncrashed</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.normal_exit</strong></span></td></tr></table><p>

   </p><p>This option also works with the Torbutton <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/crash-observer.js" target="_top">crash-observer.js</a> 

   to set the Tor state after a normal startup is detected (via the 

@@ -967,7 +967,7 @@ false positives

 extensions.torbutton.normal_exit in torbutton_uninstall_observer() during

 Firefox exit and checks this value as well during startup.

-</p></div><div class="sect2" title="5.28. Prevent session store from saving Non-Tor/Tor-loaded tabs"><div class="titlepage"><div><div><h3 class="title"><a id="id2979978"></a>5.28. Prevent session store from saving Non-Tor/Tor-loaded tabs</h3></div></div></div><p>Options: 

+</p></div><div class="sect2" title="5.28. Prevent session store from saving Non-Tor/Tor-loaded tabs"><div class="titlepage"><div><div><h3 class="title"><a id="id2934994"></a>5.28. Prevent session store from saving Non-Tor/Tor-loaded tabs</h3></div></div></div><p>Options: 

   </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.nonontor_sessionstore</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.notor_sessionstore</strong></span></td></tr></table><p>

   </p><p>If these options are enabled, the <a class="ulink" href="https://git.torproject.org/checkout/torbutton/master/src/components/nsSessionStore3.js" target="_top">replacement nsSessionStore.js</a>

   component checks the <span class="command"><strong>__tb_tor_fetched</strong></span> tag of tabs before writing them

@@ -977,7 +977,7 @@ This setting helps to satisfy the <a class="link" href="#disk">Disk Avoidance</a

 requirement, and also helps to satisfy the <a class="link" href="#state">State Separation</a> requirement in the event of Firefox

 crashes.

-</p></div><div class="sect2" title="5.29. Set user agent during Tor usage (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2980042"></a>5.29. Set user agent during Tor usage (crucial)</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.29. Set user agent during Tor usage (crucial)"><div class="titlepage"><div><div><h3 class="title"><a id="id2935059"></a>5.29. Set user agent during Tor usage (crucial)</h3></div></div></div><p>Options:

    </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.set_uagent</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.platform_override</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.oscpu_override</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.buildID_override</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.productsub_override</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.appname_override</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.appversion_override</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.useragent_override</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.useragent_vendor</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.useragent_vendorSub</strong></span></td></tr></table><p>

    </p><p>On face, user agent switching appears to be straight-forward in Firefox.

 It provides several options for controlling the browser user agent string:

@@ -1001,7 +1001,7 @@ certain resource:// files</a>. These cases are handled by Torbutton's

 </p><p>

 This setting helps to satisfy the <a class="link" href="#setpreservation">Anonymity Set Preservation</a> requirement.

-</p></div><div class="sect2" title="5.30. Spoof US English Browser"><div class="titlepage"><div><div><h3 class="title"><a id="id2980217"></a>5.30. Spoof US English Browser</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.30. Spoof US English Browser"><div class="titlepage"><div><div><h3 class="title"><a id="id2935233"></a>5.30. Spoof US English Browser</h3></div></div></div><p>Options:

 </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.spoof_english</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.spoof_charset</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.spoof_language</strong></span></td></tr></table><p>

 </p><p> This option causes Torbutton to set

 <span class="command"><strong>general.useragent.locale</strong></span>

@@ -1012,13 +1012,13 @@ This setting helps to satisfy the <a class="link" href="#setpreservation">Anonym

 well as hooking <span class="command"><strong>navigator.language</strong></span> via its <a class="link" href="#jshooks" title="5.4. Hook Dangerous Javascript">javascript hooks</a>.

  </p><p>

 This setting helps to satisfy the <a class="link" href="#setpreservation">Anonymity Set Preservation</a> and <a class="link" href="#location">Location Neutrality</a> requirements.

-</p></div><div class="sect2" title="5.31. Don't send referrer during Tor Usage"><div class="titlepage"><div><div><h3 class="title"><a id="id2980310"></a>5.31. Don't send referrer during Tor Usage</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.disable_referer</strong></span>

+</p></div><div class="sect2" title="5.31. Don't send referrer during Tor Usage"><div class="titlepage"><div><div><h3 class="title"><a id="id2935326"></a>5.31. Don't send referrer during Tor Usage</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.disable_referer</strong></span>

 </p><p> 

 This option causes Torbutton to set <a class="ulink" href="http://kb.mozillazine.org/Network.http.sendSecureXSiteReferrer" target="_top">network.http.sendSecureXSiteReferrer</a> and

 <a class="ulink" href="http://kb.mozillazine.org/Network.http.sendRefererHeader" target="_top">network.http.sendRefererHeader</a> during Tor usage.</p><p>

 This setting also does not directly satisfy any Torbutton requirement, but

 some may desire to mask their referrer for general privacy concerns.

-</p></div><div class="sect2" title="5.32. Strip platform and language off of Google Search Box queries"><div class="titlepage"><div><div><h3 class="title"><a id="id2980350"></a>5.32. Strip platform and language off of Google Search Box queries</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.fix_google_srch</strong></span>

+</p></div><div class="sect2" title="5.32. Strip platform and language off of Google Search Box queries"><div class="titlepage"><div><div><h3 class="title"><a id="id2935366"></a>5.32. Strip platform and language off of Google Search Box queries</h3></div></div></div><p>Option: <span class="command"><strong>extensions.torbutton.fix_google_srch</strong></span>

 </p><p> 

 This option causes Torbutton to use the <a class="ulink" href="https://wiki.mozilla.org/Search_Service:API" target="_top">@mozilla.org/browser/search-service;1</a>

@@ -1028,12 +1028,12 @@ platform information. This setting strips off that info while Tor is enabled.

 </p><p>

 This setting helps Torbutton to fulfill its <a class="link" href="#setpreservation">Anonymity Set Preservation</a> requirement.

-</p></div><div class="sect2" title="5.33. Automatically use an alternate search engine when presented with a Google Captcha"><div class="titlepage"><div><div><h3 class="title"><a id="id2980391"></a>5.33. Automatically use an alternate search engine when presented with a

+</p></div><div class="sect2" title="5.33. Automatically use an alternate search engine when presented with a Google Captcha"><div class="titlepage"><div><div><h3 class="title"><a id="id2935407"></a>5.33. Automatically use an alternate search engine when presented with a

 Google Captcha</h3></div></div></div><p>Options:

 </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.asked_google_captcha</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.dodge_google_captcha</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.google_redir_url</strong></span></td></tr></table><p>

 </p><p>

-Google's earch engine has rate limiting features that cause it to

+Google's search engine has rate limiting features that cause it to

 <a class="ulink" href="http://googleonlinesecurity.blogspot.com/2007/07/reason-behind-were-sorry-message.html" target="_top">present

 captchas</a> and sometimes even outright ban IPs that issue large numbers

 of search queries, especially if a lot of these queries appear to be searching

@@ -1053,7 +1053,7 @@ options are ixquick.com, bing.com, yahoo.com and scroogle.org. These are

 encoded in the preferences

 <span class="command"><strong>extensions.torbutton.redir_url.[1-4]</strong></span>.

-</p></div><div class="sect2" title="5.34. Store SSL/CA Certs in separate jars for Tor/Non-Tor (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2980471"></a>5.34. Store SSL/CA Certs in separate jars for Tor/Non-Tor (recommended)</h3></div></div></div><p>Options:

+</p></div><div class="sect2" title="5.34. Store SSL/CA Certs in separate jars for Tor/Non-Tor (recommended)"><div class="titlepage"><div><div><h3 class="title"><a id="id2935487"></a>5.34. Store SSL/CA Certs in separate jars for Tor/Non-Tor (recommended)</h3></div></div></div><p>Options:

 </p><table border="0" summary="Simple list" class="simplelist"><tr><td><span class="command"><strong>extensions.torbutton.jar_certs</strong></span></td></tr><tr><td><span class="command"><strong>extensions.torbutton.jar_ca_certs</strong></span></td></tr></table><p>

 </p><p>

@@ -1084,26 +1084,35 @@ is currently not exposed via the preferences UI.

 Torbutton has to work around a number of Firefox bugs that impact its

 security. Most of these are mentioned elsewhere in this document, but they

-have also been gathered here for reference. Several of these have fixes in

-Firefox3.0/trunk, but are listed because they still have not been backported

-to FF2.0. In order of decreasing severity, they are:

-

-   </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=392274" target="_top">Bug 392274 - Timezone

-config/chrome API</a><p>

-

-The lack of a config or API to configure the timezone requires Torbutton to

-<a class="link" href="#jshooks" title="5.4. Hook Dangerous Javascript">insert client content window javascript</a> to hook

-the Date object. Additionally, a way to <a class="ulink" href="http://pseudo-flaw.net/tor/torbutton/unmask-date.html" target="_top">remove the Date

-hooks</a> was discovered by Greg Fleischer. Worse, on Firefox 3,

-javascript sandboxing prevents most of the javascript hooks from being

-installed, including the Date hooks. On Windows and Linux, you can set the TZ

-environment variable to "UTC" as a workaround. Firefox will obey this

-environment variable for your Timezone on those platforms, but on Windows this

-does not take effect until browser restart. A fix for this has landed in

-Firefox 3.5, but still has not been backported to Firefox 3.0. The lack of an

-easy way to reliably spoof the timezone interferes with Torbutton's ability to

-fulfill its <a class="link" href="#location">Location Neutrality</a> requirement.

+have also been gathered here for reference. In order of decreasing severity,

+they are:

+

+   </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=429070" target="_top">Bug 429070 - exposing

+Components.interfaces to untrusted content leaks information about installed

+extensions</a><p>

+<a class="ulink" href="http://pseudo-flaw.net/" target="_top">Gregory Fleischer</a> demonstrated at Defcon 17 that these interfaces can

+also be used to <a class="ulink" href="http://pseudo-flaw.net/tor/torbutton/fingerprint-firefox.html" target="_top">fingerprint

+Firefox down the to the minor version</a>. Note that his test has not been

+updated since 3.5.3, hence it reports 3.5.3 for more recent Firefoxes. This

+bug interferes with Torbutton's ability to satisfy its <a class="link" href="#setpreservation">Anonymity Set Preservation</a> requirement.

+     </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=280661" target="_top">Bug 280661 - SOCKS proxy server

+connection timeout hard-coded</a><p>

+

+This bug prevents us from using the Firefox SOCKS layer directly, and

+currently requires us to ship an auxiliary HTTP proxy called <a class="ulink" href="http://www.pps.jussieu.fr/~jch/software/polipo/" target="_top">Polipo</a>. If this

+patch were landed, we would no longer need to ship Polipo, which has a number

+of privacy and security issues of its own (in addition to being unmaintained).

+    </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=418986" target="_top">Bug 418986 - window.screen

+provides a large amount of identifiable information</a><p>

+

+As <a class="link" href="#fingerprinting">mentioned above</a>, a large amount of

+information is available from <a class="ulink" href="http://developer.mozilla.org/en/docs/DOM:window.screen" target="_top">window.screen</a>.

+Currently, there is no way to obscure this information without Javascript

+hooking. This bug is a feature request to provide some other method to change

+these values. This bug interferes with Torbutton's ability to fulfill its

+<a class="link" href="#setpreservation">Anonymity Set Preservation</a>

+requirement.

    </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=435159" target="_top">Bug 435159 -

 nsNSSCertificateDB::DeleteCertificate has race conditions</a><p>

@@ -1119,6 +1128,19 @@ this functionality is considered a Torbutton security bug because cert

 isolation is considered a <a class="link" href="#state">State Separation</a>

 feature.

+      </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=575230" target="_top">Bug 575230 - Provide option to

+reduce precision of Date()</a><p>

+

+Currently it is possible to <a class="ulink" href="http://arstechnica.com/tech-policy/news/2010/02/firm-uses-typing-cadence-to-finger-unauthorized-users.ars" target="_top">fingerprint

+users based on their typing cadence</a> using the high precision timer

+available to javascript. Using this same precision, it is possible to compute

+an identifier based upon the clock drift of the client from some nominal

+source. The latter is not much of a concern for Tor users, as the variable

+delay to load and run a page is measured on the order of seconds, but the high

+precision timer can still be used to fingerprint aspects of a browser's

+javascript engine and processor, and apparently also a user's typing cadence.

+This bug hinders Torbutton's ability to satisfy its <a class="link" href="#setpreservation">Anonymity Set Preservation</a> requirement.

+

       </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=409737" target="_top">Bug 409737 -

 javascript.enabled and docShell.allowJavascript do not disable all event

 handlers</a><p>

@@ -1217,15 +1239,6 @@ when it arrives in the <span class="command"><strong>torbutton_http_observer</st

 blocking full page plugin loads. This seems to work just fine, but is a bit

 dirty.

-    </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=418986" target="_top">Bug 418986 - window.screen

-provides a large amount of identifiable information</a><p>

-

-As <a class="link" href="#fingerprinting">mentioned above</a>, a large amount of

-information is available from <a class="ulink" href="http://developer.mozilla.org/en/docs/DOM:window.screen" target="_top">window.screen</a>.

-Currently, there is no way to obscure this information without Javascript

-hooking. This bug is a feature request to provide some other method to change

-these values.

-

     </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=309524" target="_top">Bug 309524</a>

 and <a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=380556" target="_top">Bug

 380556</a> - nsIContentPolicy::shouldProcess is not called.

@@ -1252,16 +1265,6 @@ requirement and reveal a user's original IP address. Torbutton's code to

 perform this workaround has been subverted at least once already by Kyle

 Williams.

-     </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=448747" target="_top">Bug 448747 -

-Provide Mechanism to clear TLS Session IDs</a><p>

-

-As <a class="link" href="#browseroverlay" title="3.1. Browser Overlay - torbutton.xul">mentioned above</a>, Torbutton currently

-toggles <span class="command"><strong>security.enable_ssl2</strong></span> to clear the SSL

-Session ID cache via the pref observer at <a class="ulink" href="http://mxr.mozilla.org/security/source/security/manager/ssl/src/nsNSSComponent.cpp#2134" target="_top">nsNSSComponent.cpp

-line 2134</a>. This is an arcane and potentially fragile fix. It would be

-better if there were a more standard interface for accomplishing the same

-thing.

-

      </p></li><li class="listitem"><a class="ulink" href="https://bugzilla.mozilla.org/show_bug.cgi?id=419598" target="_top">Bug 419598 - 'var

 Date' is deletable</a><p>

@@ -1390,13 +1393,13 @@ or complete, but it is automated and could be turned into something useful

 with a bit of work.

        </p></li></ol></div><p>

-    </p></div><div class="sect2" title="7.2. Multi-state testing"><div class="titlepage"><div><div><h3 class="title"><a id="id2981478"></a>7.2. Multi-state testing</h3></div></div></div><p>

+    </p></div><div class="sect2" title="7.2. Multi-state testing"><div class="titlepage"><div><div><h3 class="title"><a id="id2936532"></a>7.2. Multi-state testing</h3></div></div></div><p>

 The tests in this section are geared towards a page that would instruct the

 user to toggle their Tor state after the fetch and perform some operations:

 mouseovers, stray clicks, and potentially reloads.

-   </p><div class="sect3" title="Cookies and Cache Correlation"><div class="titlepage"><div><div><h4 class="title"><a id="id2981490"></a>Cookies and Cache Correlation</h4></div></div></div><p>

+   </p><div class="sect3" title="Cookies and Cache Correlation"><div class="titlepage"><div><div><h4 class="title"><a id="id2936545"></a>Cookies and Cache Correlation</h4></div></div></div><p>

 The most obvious test is to set a cookie, ask the user to toggle tor, and then

 have them reload the page. The cookie should no longer be set if they are

 using the default Torbutton settings. In addition, it is possible to leverage

@@ -1404,11 +1407,11 @@ the cache to <a class="ulink" href="http://crypto.stanford.edu/sameorigin/safeca

 identifiers</a>. The default settings of Torbutton should also protect

 against these from persisting across Tor Toggle.

-    </p></div><div class="sect3" title="Javascript timers and event handlers"><div class="titlepage"><div><div><h4 class="title"><a id="id2981513"></a>Javascript timers and event handlers</h4></div></div></div><p>

+    </p></div><div class="sect3" title="Javascript timers and event handlers"><div class="titlepage"><div><div><h4 class="title"><a id="id2936567"></a>Javascript timers and event handlers</h4></div></div></div><p>

 Javascript can set timers and register event handlers in the hopes of fetching

 URLs after the user has toggled Torbutton. 

-    </p></div><div class="sect3" title="CSS Popups and non-script Dynamic Content"><div class="titlepage"><div><div><h4 class="title"><a id="id2981526"></a>CSS Popups and non-script Dynamic Content</h4></div></div></div><p>

+    </p></div><div class="sect3" title="CSS Popups and non-script Dynamic Content"><div class="titlepage"><div><div><h4 class="title"><a id="id2936580"></a>CSS Popups and non-script Dynamic Content</h4></div></div></div><p>

 Even if Javascript is disabled, CSS is still able to 

 <a class="ulink" href="http://www.tjkdesign.com/articles/css%20pop%20ups/" target="_top">create popup-like

@@ -1433,7 +1436,7 @@ these attacks, playing with them, and reporting what you find (and potentially

 submitting the test cases back to be run in the standard batch of Torbutton

 tests.

-   </p><div class="sect3" title="Some suggested vectors to investigate"><div class="titlepage"><div><div><h4 class="title"><a id="id2981580"></a>Some suggested vectors to investigate</h4></div></div></div><p>

+   </p><div class="sect3" title="Some suggested vectors to investigate"><div class="titlepage"><div><div><h4 class="title"><a id="id2936635"></a>Some suggested vectors to investigate</h4></div></div></div><p>

     </p><div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem">Strange ways to register Javascript <a class="ulink" href="http://en.wikipedia.org/wiki/DOM_Events" target="_top">events</a> and <a class="ulink" href="http://www.devshed.com/c/a/JavaScript/Using-Timers-in-JavaScript/" target="_top">timeouts</a> should

 be verified to actually be ineffective after Tor has been toggled.</li><li class="listitem">Other ways to cause Javascript to be executed after

 <span class="command"><strong>javascript.enabled</strong></span> has been toggled off.</li><li class="listitem">Odd ways to attempt to load plugins. Kyle Williams has had