Issue 3208 - Separate contentPolicy module into a parent and child part

lib/contentPolicy.js

Index: lib/contentPolicy.js
===================================================================
--- a/lib/contentPolicy.js
+++ b/lib/contentPolicy.js
@@ -18,39 +18,31 @@
 /**
  * @fileOverview Content policy implementation, responsible for blocking things.
  */
 
 "use strict";
 
 let {XPCOMUtils} = Cu.import("resource://gre/modules/XPCOMUtils.jsm", {});
 let {Services} = Cu.import("resource://gre/modules/Services.jsm", {});
-let {PrivateBrowsingUtils} = Cu.import("resource://gre/modules/PrivateBrowsingUtils.jsm", {});
 
 let {Utils} = require("utils");
 let {Prefs} = require("prefs");
 let {FilterStorage} = require("filterStorage");
 let {BlockingFilter, WhitelistFilter, RegExpFilter} = require("filterClasses");
 let {defaultMatcher} = require("matcher");
 let {objectMouseEventHander} = require("objectTabs");
-let {RequestNotifier} = require("requestNotifier");
 let {ElemHide} = require("elemHide");
 
 /**
  * Randomly generated class name, to be applied to collapsed nodes.
  */
 let collapsedClass = "";
 
 /**
- * Maps numerical content type IDs to strings.
- * @type Map
- */
-let types = new Map();
-
-/**
  * Public policy checking functions and auxiliary objects
  * @class
  */
 var Policy = exports.Policy =
 {
   /**
    * Set of explicitly supported content types
    * @type Set
@@ -80,16 +72,27 @@ var Policy = exports.Policy =
    * Called on module startup, initializes various exported properties.
    */
   init: function()
   {
     // whitelisted URL schemes
     for (let scheme of Prefs.whitelistschemes.toLowerCase().split(" "))
       this.whitelistSchemes.add(scheme);
 
+    let messageManager = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+                           .getService(Ci.nsIMessageListenerManager)
+                           .QueryInterface(Ci.nsIMessageBroadcaster);
+    let handler = (message => this.shouldAllow(message.data));
+    messageManager.addMessageListener("AdblockPlus:ShouldAllow", handler);
+    onShutdown.add(() => messageManager.removeMessageListener("AdblockPlus:ShouldAllow", handler));
+
+    let handler2 = () => collapsedClass;
+    messageManager.addMessageListener("AdblockPlus:GetCollapsedClass", handler2);
+    onShutdown.add(() => messageManager.removeMessageListener("AdblockPlus:GetCollapsedClass", handler2));
+
     // Generate class identifier used to collapse node and register corresponding
     // stylesheet.
     let offset = "a".charCodeAt(0);
     for (let i = 0; i < 20; i++)
       collapsedClass +=  String.fromCharCode(offset + Math.random() * 26);
 
     let collapseStyle = Services.io.newURI("data:text/css," +
         encodeURIComponent("." + collapsedClass +
@@ -98,154 +101,124 @@ var Policy = exports.Policy =
     onShutdown.add(() =>
     {
       Utils.styleService.unregisterSheet(collapseStyle, Ci.nsIStyleSheetService.USER_SHEET);
     });
   },
 
   /**
    * Checks whether a node should be blocked, hides it if necessary
-   * @param wnd {nsIDOMWindow}
-   * @param node {nsIDOMElement}
    * @param contentType {String}

[Thomas Greiner, 2015/11/11 16:52:33]

The documentation of the parameters is no longer accurate since they are no
longer passed separately.

However, the online documentation (see
http://usejsdoc.org/tags-param.html#parameters-with-properties) doesn't consider
object destructuring yet so the suggestion is to work around it by making up a
name for that object (see https://github.com/jsdoc3/jsdoc/issues/987).

FYI: Google's Closure Compiler opted for a different approach:
https://github.com/google/closure-compiler/issues/1114

[Wladimir Palant, 2015/11/11 17:43:26]

Done.

    * @param location {String}
-   * @param collapse {Boolean} true to force hiding of the node
-   * @return {Boolean} false if the node should be blocked
+   * @param frames {Object[]}
+   * @param isPrivate {Boolean}  true if the request belongs to a private browsing window
+   * @return {Object} An object containing properties block, collapse and hits
+   *                  indicating how this request should be handled.
    */
-  processNode: function(wnd, node, contentType, location, collapse)
+  shouldAllow: function({contentType, location, frames, isPrivate})
   {
-    let topWnd = wnd.top;
-    if (!topWnd || !topWnd.location || !topWnd.location.href)
-      return true;
+    let hits = [];
+
+    function addHit(frameIndex, contentType, docDomain, thirdParty, location, filter)
+    {
+      if (filter && !isPrivate)
+        FilterStorage.increaseHitCount(filter);
+      hits.push({
+        frameIndex, contentType, docDomain, thirdParty, location,
+        filter: filter ? filter.text : null
+      });
+    }
+
+    function response(allow, collapse)
+    {
+      return {allow, collapse, hits};
+    }
 
     // Ignore whitelisted schemes
     if (!this.isBlockableScheme(location))
-      return true;
+      return response(true, false);
 
     // Interpret unknown types as "other"
     if (!this.contentTypes.has(contentType))
       contentType = "OTHER";
 
-    let originWindow = Utils.getOriginWindow(wnd);
-    let wndLocation = originWindow.location.href;
+    let wndLocation = frames[0].location;
     let docDomain = getHostname(wndLocation);
     let match = null;
-    let [sitekey, sitekeyWnd] = getSitekey(wnd);
+    let [sitekey, sitekeyFrame] = getSitekey(frames);
     let nogeneric = false;
-
-    function cleanWindowLocation(wnd)
-    {
-      let url = getWindowLocation(wnd);
-      let index = url.indexOf("#");
-      if (index >= 0)
-        url = url.substring(0, index);
-
-      return url;
-    }
-
-    function addHit(match)
-    {
-      if (!PrivateBrowsingUtils.isContentWindowPrivate(wnd))
-        FilterStorage.increaseHitCount(match);
-    }
-
     if (!match && Prefs.enabled)
     {
-      let testWnd = wnd;
       let testSitekey = sitekey;
-      let testSitekeyWnd = sitekeyWnd;
-      let parentWndLocation = cleanWindowLocation(testWnd);
-      while (true)
+      let testSitekeyFrame = sitekeyFrame;
+      for (let i = 0; i < frames.length; i++)
       {
-        let testWndLocation = parentWndLocation;
-        parentWndLocation = (testWnd == testWnd.parent ? testWndLocation : cleanWindowLocation(testWnd.parent));
+        let frame = frames[i];
+        let testWndLocation = frame.location;
+        let parentWndLocation = frames[Math.min(i + 1, frames.length - 1)].location;
         let parentDocDomain = getHostname(parentWndLocation);
 
         let typeMap = RegExpFilter.typeMap.DOCUMENT;
         if (contentType == "ELEMHIDE")
           typeMap = typeMap | RegExpFilter.typeMap.ELEMHIDE;
-        let whitelistMatch = defaultMatcher.matchesAny(testWndLocation, typeMap, parentDocDomain, false, sitekey);
+        let whitelistMatch = defaultMatcher.matchesAny(testWndLocation, typeMap, parentDocDomain, false, testSitekey);
         if (whitelistMatch instanceof WhitelistFilter)
         {
-          addHit(whitelistMatch);
-          RequestNotifier.addNodeData(testWnd.document, topWnd,
-            (whitelistMatch.contentType & RegExpFilter.typeMap.DOCUMENT) ? "DOCUMENT" : "ELEMHIDE",
-            parentDocDomain, false, testWndLocation, whitelistMatch);
-          return true;
+          let whitelistType = (whitelistMatch.contentType & RegExpFilter.typeMap.DOCUMENT) ? "DOCUMENT" : "ELEMHIDE";
+          addHit(i, whitelistType, parentDocDomain, false, testWndLocation,
+              whitelistMatch);
+          return response(true, false);
         }
 
         let genericType = (contentType == "ELEMHIDE" ? "GENERICHIDE" : "GENERICBLOCK");
         let nogenericMatch = defaultMatcher.matchesAny(testWndLocation,
             RegExpFilter.typeMap[genericType], parentDocDomain, false, testSitekey);
         if (nogenericMatch instanceof WhitelistFilter)
         {
           nogeneric = true;
-
-          addHit(nogenericMatch);
-          RequestNotifier.addNodeData(testWnd.document, topWnd, genericType,
-                                      parentDocDomain, false, testWndLocation,
-                                      nogenericMatch);
+          addHit(i, genericType, parentDocDomain, false, testWndLocation,
+              nogenericMatch);
         }
 
-        if (testWnd.parent == testWnd)
-          break;
-
-        if (testWnd == testSitekeyWnd)
-          [testSitekey, testSitekeyWnd] = getSitekey(testWnd.parent);
-        testWnd = testWnd.parent;
+        if (frame == testSitekeyFrame)
+          [testSitekey, testSitekeyFrame] = getSitekey(frames.slice(i + 1));
       }
     }
 
     if (!match && contentType == "ELEMHIDE")
     {
       match = location;
       location = match.text.replace(/^.*?#/, '#');
 
       if (!match.isActiveOnDomain(docDomain))
-        return true;
+        return response(true, false);
 
       let exception = ElemHide.getException(match, docDomain);
       if (exception)
       {
-        addHit(exception);
-        RequestNotifier.addNodeData(node, topWnd, contentType, docDomain, false, location, exception);
-        return true;
+        addHit(null, contentType, docDomain, false, location, exception);

[Thomas Greiner, 2015/11/11 16:52:33]

Detail: Isn't it more common to use `-1` for a non-existent index (e.g.
Array.prototype.indexOf`)? That'd allow you to use the common `... > -1` check
instead of `typeof ... == "number"` in child/contentPolicy.

[Wladimir Palant, 2015/11/11 17:43:25]

That's what I had initially but frameIndex: -1 doesn't correctly represent the
context here. In fact, the context isn't a frame, and also not some unknown
frame but the original DOM element - so not passing anything for this parameter
seems to be the best option for me. 

[Thomas Greiner, 2015/11/11 18:07:32]

Makes sense then, I agree.

+        return response(true, false);
       }
 
       if (nogeneric && match.isGeneric())
-        return true;
+        return response(true, false);
     }
 
     let thirdParty = (contentType == "ELEMHIDE" ? false : isThirdParty(location, docDomain));
-
+    let collapse = false;
     if (!match && Prefs.enabled && RegExpFilter.typeMap.hasOwnProperty(contentType))
     {
       match = defaultMatcher.matchesAny(location, RegExpFilter.typeMap[contentType],
                                         docDomain, thirdParty, sitekey, nogeneric);
-      if (match instanceof BlockingFilter && node.ownerDocument && !this.nonVisualTypes.has(contentType))
-      {
-        let prefCollapse = (match.collapse != null ? match.collapse : !Prefs.fastcollapse);
-        if (collapse || prefCollapse)
-          schedulePostProcess(node);
-      }
+      if (match instanceof BlockingFilter && !this.nonVisualTypes.has(contentType))
+        collapse = (match.collapse != null ? match.collapse : !Prefs.fastcollapse);
+    }
+    addHit(null, contentType, docDomain, thirdParty, location, match);
 
-      // Track mouse events for objects
-      if (!match && contentType == "OBJECT" && node.nodeType == Ci.nsIDOMNode.ELEMENT_NODE)
-      {
-        node.addEventListener("mouseover", objectMouseEventHander, true);
-        node.addEventListener("mouseout", objectMouseEventHander, true);
-      }
-    }
-
-    // Store node data
-    RequestNotifier.addNodeData(node, topWnd, contentType, docDomain, thirdParty, location, match);
-    if (match)
-      addHit(match);
-
-    return !match || match instanceof WhitelistFilter;
+    return response(!match || match instanceof WhitelistFilter, collapse);
   },
 
   /**
    * Checks whether the location's scheme is blockable.
    * @param location  {nsIURI|String}
    * @return {Boolean}
    */
   isBlockableScheme: function(location)
@@ -312,307 +285,58 @@ var Policy = exports.Policy =
 
     for (let node of nodes)
       Utils.runAsync(() => refilterNode(node, entry));
   }
 };
 Policy.init();
 
 /**
- * Actual nsIContentPolicy and nsIChannelEventSink implementation
- * @class
- */
-var PolicyImplementation =
-{
-  classDescription: "Adblock Plus content policy",
-  classID: Components.ID("cfeaabe6-1dd1-11b2-a0c6-cb5c268894c9"),
-  contractID: "@adblockplus.org/abp/policy;1",
-  xpcom_categories: ["content-policy", "net-channel-event-sinks"],
-
-  /**
-   * Registers the content policy on startup.
-   */
-  init: function()
-  {
-    // Populate types map
-    let iface = Ci.nsIContentPolicy;
-    for (let name in iface)
-      if (name.indexOf("TYPE_") == 0 && name != "TYPE_DATAREQUEST")
-        types.set(iface[name], name.substr(5));
-
-    let registrar = Components.manager.QueryInterface(Ci.nsIComponentRegistrar);
-    registrar.registerFactory(this.classID, this.classDescription, this.contractID, this);
-
-    let catMan = Utils.categoryManager;
-    for (let category of this.xpcom_categories)
-      catMan.addCategoryEntry(category, this.contractID, this.contractID, false, true);
-
-    Services.obs.addObserver(this, "content-document-global-created", true);
-
-    onShutdown.add(() =>
-    {
-      Services.obs.removeObserver(this, "content-document-global-created");
-
-      for (let category of this.xpcom_categories)
-        catMan.deleteCategoryEntry(category, this.contractID, false);
-
-      registrar.unregisterFactory(this.classID, this);
-    });
-  },
-
-  //
-  // nsISupports interface implementation
-  //
-
-  QueryInterface: XPCOMUtils.generateQI([Ci.nsIContentPolicy, Ci.nsIObserver,
-    Ci.nsIChannelEventSink, Ci.nsIFactory, Ci.nsISupportsWeakReference]),
-
-  //
-  // nsIContentPolicy interface implementation
-  //
-
-  shouldLoad: function(contentType, contentLocation, requestOrigin, node, mimeTypeGuess, extra)
-  {
-    // Ignore requests without context and top-level documents
-    if (!node || contentType == Ci.nsIContentPolicy.TYPE_DOCUMENT)
-      return Ci.nsIContentPolicy.ACCEPT;
-
-    // Ignore standalone objects
-    if (contentType == Ci.nsIContentPolicy.TYPE_OBJECT && node.ownerDocument && !/^text\/|[+\/]xml$/.test(node.ownerDocument.contentType))
-      return Ci.nsIContentPolicy.ACCEPT;
-
-    let wnd = Utils.getWindow(node);
-    if (!wnd)
-      return Ci.nsIContentPolicy.ACCEPT;
-
-    // Data loaded by plugins should be associated with the document
-    if (contentType == Ci.nsIContentPolicy.TYPE_OBJECT_SUBREQUEST && node instanceof Ci.nsIDOMElement)
-      node = node.ownerDocument;
-
-    // Fix type for objects misrepresented as frames or images
-    if (contentType != Ci.nsIContentPolicy.TYPE_OBJECT && (node instanceof Ci.nsIDOMHTMLObjectElement || node instanceof Ci.nsIDOMHTMLEmbedElement))
-      contentType = Ci.nsIContentPolicy.TYPE_OBJECT;
-
-    let location = Utils.unwrapURL(contentLocation);
-    let result = Policy.processNode(wnd, node, types.get(contentType), location.spec, false);
-    return (result ? Ci.nsIContentPolicy.ACCEPT : Ci.nsIContentPolicy.REJECT_REQUEST);
-  },
-
-  shouldProcess: function(contentType, contentLocation, requestOrigin, insecNode, mimeType, extra)
-  {
-    return Ci.nsIContentPolicy.ACCEPT;
-  },
-
-  //
-  // nsIObserver interface implementation
-  //
-  observe: function(subject, topic, data, additional)
-  {
-    switch (topic)
-    {
-      case "content-document-global-created":
-      {
-        if (!(subject instanceof Ci.nsIDOMWindow) || !subject.opener)
-          return;
-
-        let uri = additional || subject.location.href;
-        if (!Policy.processNode(subject.opener, subject.opener.document, "POPUP", uri, false))
-        {
-          subject.stop();
-          Utils.runAsync(() => subject.close());
-        }
-        else if (uri == "about:blank")
-        {
-          // An about:blank pop-up most likely means that a load will be
-          // initiated asynchronously. Wait for that.
-          Utils.runAsync(() =>
-          {
-            let channel = subject.QueryInterface(Ci.nsIInterfaceRequestor)
-                                 .getInterface(Ci.nsIDocShell)
-                                 .QueryInterface(Ci.nsIDocumentLoader)
-                                 .documentChannel;
-            if (channel)
-              this.observe(subject, topic, data, channel.URI.spec);
-          });
-        }
-        break;
-      }
-    }
-  },
-
-  //
-  // nsIChannelEventSink interface implementation
-  //
-
-  asyncOnChannelRedirect: function(oldChannel, newChannel, flags, callback)
-  {
-    let result = Cr.NS_OK;
-    try
-    {
-      // nsILoadInfo.contentPolicyType was introduced in Gecko 35, then
-      // renamed to nsILoadInfo.externalContentPolicyType in Gecko 44.
-      let loadInfo = oldChannel.loadInfo;
-      let contentType = ("externalContentPolicyType" in loadInfo ?
-          loadInfo.externalContentPolicyType : loadInfo.contentPolicyType);
-      if (!contentType)
-        return;
-
-      let wnd = Utils.getRequestWindow(newChannel);
-      if (!wnd)
-        return;
-
-      if (contentType == Ci.nsIContentPolicy.TYPE_DOCUMENT)
-      {
-        if (wnd.history.length <= 1 && wnd.opener)
-        {
-          // Special treatment for pop-up windows - this will close the window
-          // rather than preventing the redirect. Note that we might not have
-          // seen the original channel yet because the redirect happened before
-          // the async code in observe() had a chance to run.
-          this.observe(wnd, "content-document-global-created", null, oldChannel.URI.spec);
-          this.observe(wnd, "content-document-global-created", null, newChannel.URI.spec);
-        }
-        return;
-      }
-
-      if (!Policy.processNode(wnd, wnd.document, types.get(contentType), newChannel.URI.spec, false))
-        result = Cr.NS_BINDING_ABORTED;
-    }
-    catch (e)
-    {
-      // We shouldn't throw exceptions here - this will prevent the redirect.
-      Cu.reportError(e);
-    }
-    finally
-    {
-      callback.onRedirectVerifyCallback(result);
-    }
-  },
-
-  //
-  // nsIFactory interface implementation
-  //
-
-  createInstance: function(outer, iid)
-  {
-    if (outer)
-      throw Cr.NS_ERROR_NO_AGGREGATION;
-    return this.QueryInterface(iid);
-  }
-};
-PolicyImplementation.init();
-
-/**
- * Nodes scheduled for post-processing (might be null).
- * @type Node[]
- */
-let scheduledNodes = null;
-
-/**
- * Schedules a node for post-processing.
- */
-function schedulePostProcess(/**Element*/ node)
-{
-  if (scheduledNodes)
-    scheduledNodes.push(node);
-  else
-  {
-    scheduledNodes = [node];
-    Utils.runAsync(postProcessNodes);
-  }
-}
-
-/**
- * Processes nodes scheduled for post-processing (typically hides them).
- */
-function postProcessNodes()
-{
-  let nodes = scheduledNodes;
-  scheduledNodes = null;
-
-  for (let node of nodes)
-  {
-    // adjust frameset's cols/rows for frames
-    let parentNode = node.parentNode;
-    if (parentNode && parentNode instanceof Ci.nsIDOMHTMLFrameSetElement)
-    {
-      let hasCols = (parentNode.cols && parentNode.cols.indexOf(",") > 0);
-      let hasRows = (parentNode.rows && parentNode.rows.indexOf(",") > 0);
-      if ((hasCols || hasRows) && !(hasCols && hasRows))
-      {
-        let index = -1;
-        for (let frame = node; frame; frame = frame.previousSibling)
-          if (frame instanceof Ci.nsIDOMHTMLFrameElement || frame instanceof Ci.nsIDOMHTMLFrameSetElement)
-            index++;
-
-        let property = (hasCols ? "cols" : "rows");
-        let weights = parentNode[property].split(",");
-        weights[index] = "0";
-        parentNode[property] = weights.join(",");
-      }
-    }
-    else
-      node.classList.add(collapsedClass);
-  }
-}
-
-/**
  * Extracts the hostname from a URL (might return null).
  */
 function getHostname(/**String*/ url) /**String*/
 {
   try
   {
     return Utils.unwrapURL(url).host;
   }
   catch(e)
   {
     return null;
   }
 }
 
 /**
- * Retrieves the sitekey of a window.
+ * Retrieves and validates the sitekey for a frame structure.
  */
-function getSitekey(wnd)
+function getSitekey(frames)
 {
-  let sitekey = null;
+  for (let frame of frames)
+  {
+    if (frame.sitekey && frame.sitekey.indexOf("_") >= 0)
+    {
+      let [key, signature] = frame.sitekey.split("_", 2);
+      key = key.replace(/=/g, "");
 
-  while (true)
-  {
-    if (wnd.document && wnd.document.documentElement)
-    {
-      let keydata = wnd.document.documentElement.getAttribute("data-adblockkey");
-      if (keydata && keydata.indexOf("_") >= 0)
-      {
-        let [key, signature] = keydata.split("_", 2);
-        key = key.replace(/=/g, "");
-
-        // Website specifies a key but is the signature valid?
-        let uri = Services.io.newURI(getWindowLocation(wnd), null, null);
-        let host = uri.asciiHost;
-        if (uri.port > 0)
-          host += ":" + uri.port;
-        let params = [
-          uri.path.replace(/#.*/, ""),  // REQUEST_URI
-          host,                         // HTTP_HOST
-          Utils.httpProtocol.userAgent  // HTTP_USER_AGENT
-        ];
-        if (Utils.verifySignature(key, signature, params.join("\0")))
-          return [key, wnd];
-      }
+      // Website specifies a key but is the signature valid?
+      let uri = Services.io.newURI(frame.location, null, null);
+      let host = uri.asciiHost;
+      if (uri.port > 0)
+        host += ":" + uri.port;
+      let params = [
+        uri.path.replace(/#.*/, ""),  // REQUEST_URI
+        host,                         // HTTP_HOST
+        Utils.httpProtocol.userAgent  // HTTP_USER_AGENT
+      ];
+      if (Utils.verifySignature(key, signature, params.join("\0")))
+        return [key, frame];
     }
-
-    if (wnd === wnd.parent)
-      break;
-
-    wnd = wnd.parent;
   }
 
-  return [sitekey, wnd];
+  return [null, null];
 }
 
 /**
  * Retrieves the location of a window.
  * @param wnd {nsIDOMWindow}
  * @return {String} window location or null on failure
  */
 function getWindowLocation(wnd)