Issue 524 - Stop using @-moz-document

lib/child/elemHide.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 /**
- * @fileOverview Hit counts for element hiding.
+ * @fileOverview Serves CSS for element hiding and processes hits.
  */
 
 try
 {
   // Hack: SDK loader masks our Components object with a getter.
   let proto = Object.getPrototypeOf(this);
   let property = Object.getOwnPropertyDescriptor(proto, "Components");
   if (property && property.get)
     delete proto.Components;
 }
 catch (e)
 {
   Cu.reportError(e);
 }
 
 let {XPCOMUtils} = Cu.import("resource://gre/modules/XPCOMUtils.jsm", {});
 let {Services} = Cu.import("resource://gre/modules/Services.jsm", {});
 
 let {shouldAllowAsync} = require("child/contentPolicy");
 let {getFrames, isPrivate} = require("child/utils");
 let {RequestNotifier} = require("child/requestNotifier");
 let {port} = require("messaging");
 let {Utils} = require("utils");
 
-// The allowXBL binding below won't have any effect on the element. For elements
-// that should be hidden however we don't return any binding at all, this makes
-// Gecko stop constructing the node - it cannot be shown.
-const allowXBL = "<bindings xmlns='http://www.mozilla.org/xbl'><binding id='dummy' bindToUntrustedContent='true'/></bindings>";
-const hideXBL = "<bindings xmlns='http://www.mozilla.org/xbl'/>";
-
 const notImplemented = () => Cr.NS_ERROR_NOT_IMPLEMENTED;
 
 /**
  * about: URL module used to count hits.
  * @class
  */
 let AboutHandler =
 {
   classID: Components.ID("{55fb7be0-1dd2-11b2-98e6-9e97caf8ba67}"),
   classDescription: "Element hiding hit registration protocol handler",
@@ skipping 29 matching lines @@
   // About module implementation
   //
 
   getURIFlags: function(uri)
   {
     return Ci.nsIAboutModule.HIDE_FROM_ABOUTABOUT;
   },
 
   newChannel: function(uri, loadInfo)
   {
-    let match = /\?(?:hit(\d+)|css)$/.exec(uri.path);
-    if (!match)
-      throw Cr.NS_ERROR_FAILURE;
+    let match = /\?hit(\d+)$/.exec(uri.path);
+    if (match)
+      return new HitRegistrationChannel(uri, loadInfo, match[1]);
 
-    if (match[1])
-      return new HitRegistrationChannel(uri, loadInfo, match[1]);
-    else
-      return new StyleDataChannel(uri, loadInfo);
+    match = /\?css(?:=(.*?))?$/.exec(uri.path);
+    if (match)
+    {
+      return new StyleDataChannel(uri, loadInfo,
+            match[1] ? decodeURIComponent(match[1]) : null);
+    }
+
+    throw Cr.NS_ERROR_FAILURE;
   },
 
   QueryInterface: XPCOMUtils.generateQI([Ci.nsIFactory, Ci.nsIAboutModule])
 };
 AboutHandler.init();
 
 /**
  * Base class for channel implementations, subclasses usually only need to
  * override BaseChannel._getResponse() method.
  * @constructor
@@ skipping 88 matching lines @@
 
   isPending: () => false,
   cancel: notImplemented,
   suspend: notImplemented,
   resume: notImplemented,
 
   QueryInterface: XPCOMUtils.generateQI([Ci.nsIChannel, Ci.nsIRequest])
 };
 
 /**
  * Channel returning CSS data for the global stylesheet.

[kzar, 2016/10/06 12:10:46]

Nit: I guess this comment should be updated now it's also for domain specific
stylesheets.

[Wladimir Palant, 2016/10/06 12:27:28]

Done.

  * @constructor
  */
-function StyleDataChannel(uri, loadInfo)
+function StyleDataChannel(uri, loadInfo, domain)
 {
   BaseChannel.call(this, uri, loadInfo);
+  this._domain = domain;
 }
 StyleDataChannel.prototype = {
   __proto__: BaseChannel.prototype,
   contentType: "text/css",
+  _domain: null,
 
   _getResponse: function()
   {
     function escapeChar(match)
     {
       return "\\" + match.charCodeAt(0).toString(16) + " ";
     }
 
     // Would be great to avoid sync messaging here but nsIStyleSheetService
     // insists on opening channels synchronously.
-    let domains = port.emitSync("getSelectors");
+    let [selectors, keys] = (this._domain ?
+        port.emitSync("getSelectorsForDomain", this._domain) :

[kzar, 2016/10/06 12:10:46]

Dumb question but how does getSelectorsForDomain and getUncondtionalSelectors
resolve to ElemHide.getSelectorsForDomain and ElemHide.getUncondtionalSelectors?
I can't see where you've required them.

[Wladimir Palant, 2016/10/06 12:27:28]

This is the content process - we cannot require ElemHide here (at least not
without duplicating all the data which we don't want). This is a message sent to
the parent process, elemHideFF.js will produce the proper response then.

[kzar, 2016/10/06 13:02:32]

Ah I see.

+        port.emitSync("getUnconditionalSelectors"));
 
     let cssPrefix = "{-moz-binding: url(about:abp-elemhide?hit";
     let cssSuffix = "#dummy) !important;}\n";
     let result = [];
 
-    for (let [domain, selectors] of domains)
+    for (let i = 0; i < selectors.length; i++)
     {
-      if (domain)
-      {
-        result.push('@-moz-document domain("',
-            domain.replace(/[^\x01-\x7F]/g, escapeChar)
-                  .split(",").join('"),domain("'),
-            '"){\n');
-      }
-      else
-      {
-        // Only allow unqualified rules on a few protocols to prevent them
-        // from blocking chrome content
-        result.push('@-moz-document url-prefix("http://"),',
-            'url-prefix("https://"),url-prefix("mailbox://"),',
-            'url-prefix("imap://"),url-prefix("news://"),',
-            'url-prefix("snews://"){\n');
-      }
-
-      for (let [selector, key] of selectors)
-      {
-        result.push(selector.replace(/[^\x01-\x7F]/g, escapeChar),
-            cssPrefix, key, cssSuffix);
-      }
-
-      result.push("}\n");
+      let selector = selectors[i];
+      let key = keys[i];
+      result.push(selector.replace(/[^\x01-\x7F]/g, escapeChar),
+          cssPrefix, key, cssSuffix);
     }
 
     return result.join("");
   }
 };
 
 /**
  * Channel returning data for element hiding hits.
  * @constructor
  */
 function HitRegistrationChannel(uri, loadInfo, key)
 {
   BaseChannel.call(this, uri, loadInfo);
   this.key = key;
 }
 HitRegistrationChannel.prototype = {
   __proto__: BaseChannel.prototype,
   key: null,
   contentType: "text/xml",
 
   _getResponse: function()
   {
-    return new Promise((resolve, reject) =>
+    let window = Utils.getRequestWindow(this);
+    port.emitWithResponse("registerElemHideHit", {
+      key: this.key,
+      frames: getFrames(window),
+      isPrivate: isPrivate(window)
+    }).then(hit =>
     {
-      let window = Utils.getRequestWindow(this);
-      shouldAllowAsync(window, window.document, "ELEMHIDE", this.key, allow =>
-      {
-        resolve(allow ? allowXBL : hideXBL);
-      });
+      if (hit)
+        RequestNotifier.addNodeData(window.document, window.top, hit);
     });
+    return "<bindings xmlns='http://www.mozilla.org/xbl'/>";
   }
 };
 
 let observer = {
   QueryInterface: XPCOMUtils.generateQI([
     Ci.nsIObserver, Ci.nsISupportsWeakReference
   ]),
 
   topic: "document-element-inserted",
   styleURL: Utils.makeURI("about:abp-elemhide?css"),
@@ skipping 61 matching lines @@
           utils.addSheet(this.sheet, Ci.nsIStyleSheetService.USER_SHEET);
         }
         catch (e)
         {
           // Ignore NS_ERROR_ILLEGAL_VALUE - it will be thrown if we try to add
           // the stylesheet multiple times to the same document (the observer
           // will be notified twice for some documents).
           if (e.result != Cr.NS_ERROR_ILLEGAL_VALUE)
             throw e;
         }
+
+        let host = subject.location.hostname;
+        if (host)
+        {
+          try
+          {
+            utils.loadSheetUsingURIString(this.styleURL.spec + "=" +
+                encodeURIComponent(host), Ci.nsIStyleSheetService.USER_SHEET);
+          }
+          catch (e)
+          {
+            // Ignore NS_ERROR_ILLEGAL_VALUE - it will be thrown if we try to add
+            // the stylesheet multiple times to the same document (the observer
+            // will be notified twice for some documents).
+            if (e.result != Cr.NS_ERROR_ILLEGAL_VALUE)
+              throw e;
+          }
+        }
       }
       else if (filter)
       {
         RequestNotifier.addNodeData(window.document, window.top, {
           contentType, docDomain, thirdParty, location, filter, filterType
         });
       }
     });
   }
 };
 observer.init();