Issue 4191 - Restore rules for reinjected stylesheets

include.preload.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/>.
  */
 
 var MutationObserver = window.MutationObserver || window.WebKitMutationObserver;
 var SELECTOR_GROUP_SIZE = 200;
-var id = Math.random().toString(36).substr(2);
 
 var typeMap = {
   "img": "IMAGE",
   "input": "IMAGE",
   "picture": "IMAGE",
   "audio": "MEDIA",
   "video": "MEDIA",
   "frame": "SUBDOCUMENT",
   "iframe": "SUBDOCUMENT",
   "object": "OBJECT",
@@ skipping 140 matching lines @@
           );
       }
     }
   );
 }
 
 function checkSitekey()
 {
   var attr = document.documentElement.getAttribute("data-adblockkey");
   if (attr)
-    ext.backgroundPage.sendMessage({type: "filter.addKey", token: attr});
+    ext.backgroundPage.sendMessage({type: "filters.addKey", token: attr});
 }
 
 function getContentDocument(element)
 {
   try
   {
     return element.contentDocument;
   }
   catch (e)
   {
@@ skipping 135 matching lines @@
   },
 
   disconnect: function()
   {
     this.document.removeEventListener("DOMContentLoaded", this.trace);
     this.observer.disconnect();
     clearTimeout(this.timeout);
   }
 };
 
-function reinjectStyleSheetWhenRemoved(document, style)
-{
-  if (!MutationObserver)
-    return null;
-
-  var rules = style.sheet.rules;
-  var parentNode = style.parentNode;
-  var observer = new MutationObserver(function()
-  {
-    if (style.parentNode != parentNode)
-    {
-      parentNode.appendChild(style);
-
-      if (style.sheet.rules.length == 0)
-      {
-        for (var i = 0; i < rules.length; i += 1)
-          style.sheet.addRule(rules[i].selectorText, "display: none !important;");
-
-        style.id = id;
-        injectJS(
-          function(id)
-          {
-            var style = document.getElementById(id) ||
-                        document.documentElement.shadowRoot.getElementById(id);
-            style.removeAttribute("id");
-            Object.defineProperty(style.sheet, "disabled",
-                                  {value: false, enumerable: true});
-          }, id
-        );
-      }
-    }
-  });
-
-  observer.observe(parentNode, {childList: true});
-  return observer;
-}
-
-function injectJS(f)
-{
-  var args = JSON.stringify(Array.prototype.slice.call(arguments, 1));
-  args = args.substring(1, args.length - 1);
-  var codeString = "(" + f.toString() + ")(" + args + ");";
-
+function runInDocument(document, fn, arg)
+{
   var script = document.createElement("script");
+  script.type = "application/javascript";
   script.async = false;
-  script.textContent = codeString;
+  script.textContent = "(" + fn + ")(" + JSON.stringify(arg) + ");";
   document.documentElement.appendChild(script);
   document.documentElement.removeChild(script);
-}
-
-function protectStyleSheet(document, style)
-{
-  style.id = id;
-
-  var protector = function(id)
-  {
-    var style = document.getElementById(id) ||
-                document.documentElement.shadowRoot.getElementById(id);
-    style.removeAttribute("id");
-
-    var i;
-    var disableables = [style, style.sheet];
-    for (i = 0; i < disableables.length; i += 1)
-      Object.defineProperty(disableables[i], "disabled",
-                            {value: false, enumerable: true});
-
-    var methods = ["deleteRule", "removeRule"];
-    for (i = 0; i < methods.length; i += 1)
-    {
-      if (methods[i] in CSSStyleSheet.prototype)
-      {
-        (function(method)
-        {
-          var original = CSSStyleSheet.prototype[method];
-          CSSStyleSheet.prototype[method] = function(index)
-          {
-            if (this != style.sheet)
-              original.call(this, index);
-          };
-        }(methods[i]));
-      }
-    }
-  };
-
-  injectJS(protector, id);
 }
 
 // Neither Chrome[1] nor Safari allow us to intercept WebSockets, and therefore
 // some ad networks are misusing them as a way to serve adverts and circumvent
 // us. As a workaround we wrap WebSocket, preventing blocked WebSocket
 // connections from being opened.
 // [1] - https://bugs.chromium.org/p/chromium/issues/detail?id=129353
-function wrapWebSocket()
+function wrapWebSocket(document)
 {
   if (typeof WebSocket == "undefined")
     return;
 
-  var eventName = "abpws-" + id;
+  var eventName = "abpws-" + Math.random().toString(36).substr(2);
 
   document.addEventListener(eventName, function(event)
   {
     ext.backgroundPage.sendMessage({
       type: "websocket-request",
       url: event.detail.url
     }, function (block)
     {
       document.dispatchEvent(
         new CustomEvent(eventName + "-" + event.detail.url, {detail: block})
       );
     });
   });
 
-  function wrapper(eventName)
+  runInDocument(document, function(eventName)
   {
     // As far as possible we must track everything we use that could be
     // sabotaged by the website later in order to circumvent us.
     var RealWebSocket = WebSocket;
-    var closeWebSocket = RealWebSocket.prototype.close;
-    var document = window.document;
-    var addEventListener = document.addEventListener;
-    var removeEventListener = document.removeEventListener;
-    var dispatchEvent = document.dispatchEvent;
+    var closeWebSocket = Function.prototype.call.bind(RealWebSocket.prototype.close);
+    var addEventListener = document.addEventListener.bind(document);
+    var removeEventListener = document.removeEventListener.bind(document);
+    var dispatchEvent = document.dispatchEvent.bind(document);
     var CustomEvent = window.CustomEvent;
-    var boundCall = Function.prototype.call.bind(Function.prototype.call);
-    // (These two functions are usually the same, but since Safari 9 considers
-    //  WebSocket to be an object rather than a function we must track both.)
-    var toString = Function.prototype.toString;
-    var wsToString = RealWebSocket.toString;
-
-    function checkRequest(url, protocols, callback)
+
+    function checkRequest(url, callback)
     {
       var incomingEventName = eventName + "-" + url;
       function listener(event)
       {
         callback(event.detail);
-        boundCall(removeEventListener, document, incomingEventName, listener);
-      }
-      boundCall(addEventListener, document, incomingEventName, listener);
-
-      boundCall(dispatchEvent, document, new CustomEvent(eventName, {
-        detail: {url: url, protocols: protocols}
+        removeEventListener(incomingEventName, listener);
+      }
+      addEventListener(incomingEventName, listener);
+
+      dispatchEvent(new CustomEvent(eventName, {
+        detail: {url: url}
       }));
     }
 
-    function wrappedToString()
-    {
-      if (this === WebSocket)
-        return boundCall(wsToString, RealWebSocket);
-      if (this === wrappedToString)
-        return boundCall(toString, toString);
-      return boundCall(toString, this);
-    };
-    Function.prototype.toString = wrappedToString;
-
-    WebSocket = function(url, protocols)
-    {
+    WebSocket = function WrappedWebSocket(url, protocols)
+    {
+      // Throw correct exceptions if the constructor is used improperly.
+      if (!(this instanceof WrappedWebSocket)) return RealWebSocket();
+      if (arguments.length < 1) return new RealWebSocket();
+
       var websocket = new RealWebSocket(url, protocols);
 
-      checkRequest(url, protocols, function(blocked)
+      checkRequest(websocket.url, function(blocked)
       {
         if (blocked)
-          boundCall(closeWebSocket, websocket);
+          closeWebSocket(websocket);
       });
 
       return websocket;
-    };
+    }.bind();
+
     Object.defineProperties(WebSocket, {
-      CONNECTING: {value: 0, enumerable: true},
-      OPEN: {value: 1, enumerable: true},
-      CLOSING: {value: 2, enumerable: true},
-      CLOSED: {value: 3, enumerable: true}
+      CONNECTING: {value: RealWebSocket.CONNECTING, enumerable: true},
+      OPEN: {value: RealWebSocket.OPEN, enumerable: true},
+      CLOSING: {value: RealWebSocket.CLOSING, enumerable: true},
+      CLOSED: {value: RealWebSocket.CLOSED, enumerable: true},
+      prototype: {value: RealWebSocket.prototype}
     });
-    WebSocket.prototype = RealWebSocket.prototype;
+
     RealWebSocket.prototype.constructor = WebSocket;
-  }
-
-  injectJS(wrapper, eventName);
+  }, eventName);
 }
 
 function init(document)
 {
   var shadow = null;
   var style = null;
   var observer = null;
   var tracer = null;
 
-  wrapWebSocket();
+  wrapWebSocket(document);
 
   function getPropertyFilters(callback)
   {
     ext.backgroundPage.sendMessage({
       type: "filters.get",
       what: "cssproperties"
     }, callback);
   }
   var propertyFilters = new CSSPropertyFilters(window, getPropertyFilters,
                                                addElemHideSelectors);
 
   // Use Shadow DOM if available to don't mess with web pages that rely on
   // the order of their own <style> tags (#309).
   //
   // However, creating a shadow root breaks running CSS transitions. So we
   // have to create the shadow root before transistions might start (#452).
   //
   // Also, using shadow DOM causes issues on some Google websites,
   // including Google Docs, Gmail and Blogger (#1770, #2602, #2687).
   if ("createShadowRoot" in document.documentElement &&
       !/\.(?:google|blogger)\.com$/.test(document.domain))
   {
     shadow = document.documentElement.createShadowRoot();
     shadow.appendChild(document.createElement("shadow"));
+
+    // Stop the website from messing with our shadowRoot
+    runInDocument(document, function()
+    {
+      var ourShadowRoot = document.documentElement.shadowRoot;
+      var desc = Object.getOwnPropertyDescriptor(Element.prototype, "shadowRoot");
+      var shadowRoot = Function.prototype.call.bind(desc.get);
+
+      Object.defineProperty(Element.prototype, "shadowRoot", {
+        conifgurable: true, enumerable: true, get: function()
+        {
+          var shadow = shadowRoot(this);
+          return shadow == ourShadowRoot ? null : shadow;
+        }
+      });
+    }, null);
   }
 
   function addElemHideSelectors(selectors)
   {
     if (selectors.length == 0)
       return;
 
     if (!style)
     {
       // Create <style> element lazily, only if we add styles. Add it to
       // the shadow DOM if possible. Otherwise fallback to the <head> or
       // <html> element. If we have injected a style element before that
       // has been removed (the sheet property is null), create a new one.
       style = document.createElement("style");
       (shadow || document.head || document.documentElement).appendChild(style);
 
       // It can happen that the frame already navigated to a different
       // document while we were waiting for the background page to respond.
       // In that case the sheet property will stay null, after addind the
       // <style> element to the shadow DOM.
       if (!style.sheet)
         return;
-
-      observer = reinjectStyleSheetWhenRemoved(document, style);
-      protectStyleSheet(document, style);
     }
 
     // If using shadow DOM, we have to add the ::content pseudo-element
     // before each selector, in order to match elements within the
     // insertion point.
     if (shadow)
     {
       var preparedSelectors = [];
       for (var i = 0; i < selectors.length; i++)
       {
@@ skipping 102 matching lines @@
   }, true);
 
   return updateStylesheet;
 }
 
 if (document instanceof HTMLDocument)
 {
   checkSitekey();
   window.updateStylesheet = init(document);
 }