The Tor Browser: netwerk/protocol/http/UserAgentOverrides.jsm@6474c204b198 (annotated)

netwerk/protocol/http/UserAgentOverrides.jsm@6474c204b198 (annotated)

netwerk/protocol/http/UserAgentOverrides.jsm

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 this.EXPORTED_SYMBOLS = [ "UserAgentOverrides" ];
 const Ci = Components.interfaces;
 const Cc = Components.classes;
 Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
 Components.utils.import("resource://gre/modules/Services.jsm");
 Components.utils.import("resource://gre/modules/UserAgentUpdates.jsm");
 const OVERRIDE_MESSAGE = "Useragent:GetOverride";
 const PREF_OVERRIDES_ENABLED = "general.useragent.site_specific_overrides";
 const DEFAULT_UA = Cc["@mozilla.org/network/protocol;1?name=http"]
                      .getService(Ci.nsIHttpProtocolHandler)
                      .userAgent;
 const MAX_OVERRIDE_FOR_HOST_CACHE_SIZE = 250;
 XPCOMUtils.defineLazyServiceGetter(this, "ppmm",
                                   "@mozilla.org/parentprocessmessagemanager;1",
                                   "nsIMessageListenerManager");  // Might have to make this broadcast?
 var gPrefBranch;
 var gOverrides = new Map;
 var gUpdatedOverrides;
 var gOverrideForHostCache = new Map;
 var gInitialized = false;
 var gOverrideFunctions = [
   function (aHttpChannel) UserAgentOverrides.getOverrideForURI(aHttpChannel.URI)
 ];
 var gBuiltUAs = new Map;
 this.UserAgentOverrides = {
   init: function uao_init() {
     if (gInitialized)
       return;
     gPrefBranch = Services.prefs.getBranch("general.useragent.override.");
     gPrefBranch.addObserver("", buildOverrides, false);
     ppmm.addMessageListener(OVERRIDE_MESSAGE, this);
     Services.prefs.addObserver(PREF_OVERRIDES_ENABLED, buildOverrides, false);
     try {
       Services.obs.addObserver(HTTP_on_modify_request, "http-on-modify-request", false);
     } catch (x) {
       // The http-on-modify-request notification is disallowed in content processes.
     }
     UserAgentUpdates.init(function(overrides) {
       gOverrideForHostCache.clear();
       if (overrides) {
         for (let domain in overrides) {
           overrides[domain] = getUserAgentFromOverride(overrides[domain]);
         }
         overrides.get = function(key) this[key];
       }
       gUpdatedOverrides = overrides;
     });
     buildOverrides();
     gInitialized = true;
   },
   addComplexOverride: function uao_addComplexOverride(callback) {
     // Add to front of array so complex overrides have precedence
     gOverrideFunctions.unshift(callback);
   },
   getOverrideForURI: function uao_getOverrideForURI(aURI) {
     let host = aURI.asciiHost;
     if (!gInitialized ||
         (!gOverrides.size && !gUpdatedOverrides) ||
         !(host)) {
       return null;
     }
     let override = gOverrideForHostCache.get(host);
     if (override !== undefined)
       return override;
     function findOverride(overrides) {
       let searchHost = host;
       let userAgent = overrides.get(searchHost);
       while (!userAgent) {
         let dot = searchHost.indexOf('.');
         if (dot === -1) {
           return null;
         }
         searchHost = searchHost.slice(dot + 1);
         userAgent = overrides.get(searchHost);
       }
       return userAgent;
     }
     override = (gOverrides.size && findOverride(gOverrides))
             || (gUpdatedOverrides && findOverride(gUpdatedOverrides));
     if (gOverrideForHostCache.size >= MAX_OVERRIDE_FOR_HOST_CACHE_SIZE) {
       gOverrideForHostCache.clear();
     }
     gOverrideForHostCache.set(host, override);
     return override;
   },
   uninit: function uao_uninit() {
     if (!gInitialized)
       return;
     gInitialized = false;
     gPrefBranch.removeObserver("", buildOverrides);
     Services.prefs.removeObserver(PREF_OVERRIDES_ENABLED, buildOverrides);
     Services.obs.removeObserver(HTTP_on_modify_request, "http-on-modify-request");
   },
   receiveMessage: function(aMessage) {
     let name = aMessage.name;
     switch (name) {
       case OVERRIDE_MESSAGE:
         let uri = aMessage.data.uri;
         return this.getOverrideForURI(uri);
       default:
         throw("Wrong Message in UserAgentOverride: " + name);
     }
   }
 };
 function getUserAgentFromOverride(override)
 {
   let userAgent = gBuiltUAs.get(override);
   if (userAgent !== undefined) {
     return userAgent;
   }
   let [search, replace] = override.split("#", 2);
   if (search && replace) {
     userAgent = DEFAULT_UA.replace(new RegExp(search, "g"), replace);
   } else {
     userAgent = override;
   }
   gBuiltUAs.set(override, userAgent);
   return userAgent;
 }
 function buildOverrides() {
   gOverrides.clear();
   gOverrideForHostCache.clear();
   if (!Services.prefs.getBoolPref(PREF_OVERRIDES_ENABLED))
     return;
   let builtUAs = new Map;
   let domains = gPrefBranch.getChildList("");
   for (let domain of domains) {
     let override = gPrefBranch.getCharPref(domain);
     let userAgent = getUserAgentFromOverride(override);
     if (userAgent != DEFAULT_UA) {
       gOverrides.set(domain, userAgent);
     }
   }
 }
 function HTTP_on_modify_request(aSubject, aTopic, aData) {
   let channel = aSubject.QueryInterface(Ci.nsIHttpChannel);
   for (let callback of gOverrideFunctions) {
     let modifiedUA = callback(channel, DEFAULT_UA);
     if (modifiedUA) {
       channel.setRequestHeader("User-Agent", modifiedUA, false);
       return;
     }
   }
 }

The Tor Browser / annotate

netwerk/protocol/http/UserAgentOverrides.jsm@6474c204b198 (annotated)

netwerk/protocol/http/UserAgentOverrides.jsm