1 files changed, 680 insertions, 0 deletions
diff --git a/devtools/server/actors/addon/webextension-inspected-window.js b/devtools/server/actors/addon/webextension-inspected-window.js
new file mode 100644
index 0000000000..e69a206c9d
--- /dev/null
+++ b/devtools/server/actors/addon/webextension-inspected-window.js
@@ -0,0 +1,680 @@
+/* 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";
+
+const { Actor } = require("resource://devtools/shared/protocol.js");
+const {
+  webExtensionInspectedWindowSpec,
+} = require("resource://devtools/shared/specs/addon/webextension-inspected-window.js");
+
+const {
+  DevToolsServer,
+} = require("resource://devtools/server/devtools-server.js");
+
+loader.lazyGetter(
+  this,
+  "NodeActor",
+  () =>
+    require("resource://devtools/server/actors/inspector/node.js").NodeActor,
+  true
+);
+
+// A weak set of the documents for which a warning message has been
+// already logged (so that we don't keep emitting the same warning if an
+// extension keeps calling the devtools.inspectedWindow.eval API method
+// when it fails to retrieve a result, but we do log the warning message
+// if the user reloads the window):
+//
+// WeakSet<Document>
+const deniedWarningDocuments = new WeakSet();
+
+function isSystemPrincipalWindow(window) {
+  return window.document.nodePrincipal.isSystemPrincipal;
+}
+
+// Create the exceptionInfo property in the format expected by a
+// WebExtension inspectedWindow.eval API calls.
+function createExceptionInfoResult(props) {
+  return {
+    exceptionInfo: {
+      isError: true,
+      code: "E_PROTOCOLERROR",
+      description: "Unknown Inspector protocol error",
+
+      // Apply the passed properties.
+      ...props,
+    },
+  };
+}
+
+// Show a warning message in the webconsole when an extension
+// eval request has been denied, so that the user knows about it
+// even if the extension doesn't report the error itself.
+function logAccessDeniedWarning(window, callerInfo, extensionPolicy) {
+  // Do not log the same warning multiple times for the same document.
+  if (deniedWarningDocuments.has(window.document)) {
+    return;
+  }
+
+  deniedWarningDocuments.add(window.document);
+
+  const { name } = extensionPolicy;
+
+  // System principals have a null nodePrincipal.URI and so we use
+  // the url from window.location.href.
+  const reportedURIorPrincipal = isSystemPrincipalWindow(window)
+    ? Services.io.newURI(window.location.href)
+    : window.document.nodePrincipal;
+
+  const error = Cc["@mozilla.org/scripterror;1"].createInstance(
+    Ci.nsIScriptError
+  );
+
+  const msg = `The extension "${name}" is not allowed to access ${reportedURIorPrincipal.spec}`;
+
+  const innerWindowId = window.windowGlobalChild.innerWindowId;
+
+  const errorFlag = 0;
+
+  let { url, lineNumber } = callerInfo;
+
+  const callerURI = callerInfo.url && Services.io.newURI(callerInfo.url);
+
+  // callerInfo.url is not the full path to the file that called the WebExtensions
+  // API yet (Bug 1448878), and so we associate the error to the url of the extension
+  // manifest.json file as a fallback.
+  if (callerURI.filePath === "/") {
+    url = extensionPolicy.getURL("/manifest.json");
+    lineNumber = null;
+  }
+
+  error.initWithWindowID(
+    msg,
+    url,
+    lineNumber,
+    0,
+    0,
+    errorFlag,
+    "webExtensions",
+    innerWindowId
+  );
+  Services.console.logMessage(error);
+}
+
+function extensionAllowedToInspectPrincipal(extensionPolicy, principal) {
+  if (principal.isNullPrincipal) {
+    // data: and sandboxed documents.
+    //
+    // Rather than returning true unconditionally, we go through additional
+    // checks to prevent execution in sandboxed documents created by principals
+    // that extensions cannot access otherwise.
+    principal = principal.precursorPrincipal;
+    if (!principal) {
+      // Top-level about:blank, etc.
+      return true;
+    }
+  }
+  if (!principal.isContentPrincipal) {
+    return false;
+  }
+  const principalURI = principal.URI;
+  if (principalURI.schemeIs("https") || principalURI.schemeIs("http")) {
+    if (WebExtensionPolicy.isRestrictedURI(principalURI)) {
+      return false;
+    }
+    if (extensionPolicy.quarantinedFromURI(principalURI)) {
+      return false;
+    }
+    // Common case: http(s) allowed.
+    return true;
+  }
+
+  if (principalURI.schemeIs("moz-extension")) {
+    // Ordinarily, we don't allow extensions to execute arbitrary code in
+    // their own context. The devtools.inspectedWindow.eval API is a special
+    // case - this can only be used through the devtools_page feature, which
+    // requires the user to open the developer tools first. If an extension
+    // really wants to debug itself, we let it do so.
+    return extensionPolicy.id === principal.addonId;
+  }
+
+  if (principalURI.schemeIs("file")) {
+    return true;
+  }
+
+  return false;
+}
+
+class CustomizedReload {
+  constructor(params) {
+    this.docShell = params.targetActor.window.docShell;
+    this.docShell.QueryInterface(Ci.nsIWebProgress);
+
+    this.inspectedWindowEval = params.inspectedWindowEval;
+    this.callerInfo = params.callerInfo;
+
+    this.ignoreCache = params.ignoreCache;
+    this.injectedScript = params.injectedScript;
+
+    this.customizedReloadWindows = new WeakSet();
+  }
+
+  QueryInterface = ChromeUtils.generateQI([
+    "nsIWebProgressListener",
+    "nsISupportsWeakReference",
+  ]);
+
+  get window() {
+    return this.docShell.DOMWindow;
+  }
+
+  get webNavigation() {
+    return this.docShell
+      .QueryInterface(Ci.nsIInterfaceRequestor)
+      .getInterface(Ci.nsIWebNavigation);
+  }
+
+  get browsingContext() {
+    return this.docShell.browsingContext;
+  }
+
+  start() {
+    if (!this.waitForReloadCompleted) {
+      this.waitForReloadCompleted = new Promise((resolve, reject) => {
+        this.resolveReloadCompleted = resolve;
+        this.rejectReloadCompleted = reject;
+
+        let reloadFlags = Ci.nsIWebNavigation.LOAD_FLAGS_NONE;
+
+        if (this.ignoreCache) {
+          reloadFlags |= Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE;
+        }
+
+        try {
+          if (this.injectedScript) {
+            // Listen to the newly created document elements only if there is an
+            // injectedScript to evaluate.
+            Services.obs.addObserver(this, "initial-document-element-inserted");
+          }
+
+          // Watch the loading progress and clear the current CustomizedReload once the
+          // page has been reloaded (or if its reloading has been interrupted).
+          this.docShell.addProgressListener(
+            this,
+            Ci.nsIWebProgress.NOTIFY_STATE_DOCUMENT
+          );
+
+          this.webNavigation.reload(reloadFlags);
+        } catch (err) {
+          // Cancel the injected script listener if the reload fails
+          // (which will also report the error by rejecting the promise).
+          this.stop(err);
+        }
+      });
+    }
+
+    return this.waitForReloadCompleted;
+  }
+
+  observe(subject, topic, data) {
+    if (topic !== "initial-document-element-inserted") {
+      return;
+    }
+
+    const document = subject;
+    const window = document?.defaultView;
+
+    // Filter out non interesting documents.
+    if (!document || !document.location || !window) {
+      return;
+    }
+
+    const subjectDocShell = window.docShell;
+
+    // Keep track of the set of window objects where we are going to inject
+    // the injectedScript: the top level window and all its descendant
+    // that are still of type content (filtering out loaded XUL pages, if any).
+    if (window == this.window) {
+      this.customizedReloadWindows.add(window);
+    } else if (subjectDocShell.sameTypeParent) {
+      const parentWindow = subjectDocShell.sameTypeParent.domWindow;
+      if (parentWindow && this.customizedReloadWindows.has(parentWindow)) {
+        this.customizedReloadWindows.add(window);
+      }
+    }
+
+    if (this.customizedReloadWindows.has(window)) {
+      const { apiErrorResult } = this.inspectedWindowEval(
+        this.callerInfo,
+        this.injectedScript,
+        {},
+        window
+      );
+
+      // Log only apiErrorResult, because no one is waiting for the
+      // injectedScript result, and any exception is going to be logged
+      // in the inspectedWindow webconsole.
+      if (apiErrorResult) {
+        console.error(
+          "Unexpected Error in injectedScript during inspectedWindow.reload for",
+          `${this.callerInfo.url}:${this.callerInfo.lineNumber}`,
+          apiErrorResult
+        );
+      }
+    }
+  }
+
+  onStateChange(webProgress, request, state, status) {
+    if (webProgress.DOMWindow !== this.window) {
+      return;
+    }
+
+    if (state & Ci.nsIWebProgressListener.STATE_STOP) {
+      if (status == Cr.NS_BINDING_ABORTED) {
+        // The customized reload has been interrupted and we can clear
+        // the CustomizedReload and reject the promise.
+        const url = this.window.location.href;
+        this.stop(
+          new Error(
+            `devtools.inspectedWindow.reload on ${url} has been interrupted`
+          )
+        );
+      } else {
+        // Once the top level frame has been loaded, we can clear the customized reload
+        // and resolve the promise.
+        this.stop();
+      }
+    }
+  }
+
+  stop(error) {
+    if (this.stopped) {
+      return;
+    }
+
+    this.docShell.removeProgressListener(this);
+
+    if (this.injectedScript) {
+      Services.obs.removeObserver(this, "initial-document-element-inserted");
+    }
+
+    if (error) {
+      this.rejectReloadCompleted(error);
+    } else {
+      this.resolveReloadCompleted();
+    }
+
+    this.stopped = true;
+  }
+}
+
+class WebExtensionInspectedWindowActor extends Actor {
+  /**
+   * Created the WebExtension InspectedWindow actor
+   */
+  constructor(conn, targetActor) {
+    super(conn, webExtensionInspectedWindowSpec);
+    this.targetActor = targetActor;
+  }
+
+  destroy(conn) {
+    super.destroy();
+
+    if (this.customizedReload) {
+      this.customizedReload.stop(
+        new Error("WebExtensionInspectedWindowActor destroyed")
+      );
+      delete this.customizedReload;
+    }
+
+    if (this._dbg) {
+      this._dbg.disable();
+      delete this._dbg;
+    }
+  }
+
+  get dbg() {
+    if (this._dbg) {
+      return this._dbg;
+    }
+
+    this._dbg = this.targetActor.makeDebugger();
+    return this._dbg;
+  }
+
+  get window() {
+    return this.targetActor.window;
+  }
+
+  get webNavigation() {
+    return this.targetActor.webNavigation;
+  }
+
+  createEvalBindings(dbgWindow, options) {
+    const bindings = Object.create(null);
+
+    let selectedDOMNode;
+
+    if (options.toolboxSelectedNodeActorID) {
+      const actor = DevToolsServer.searchAllConnectionsForActor(
+        options.toolboxSelectedNodeActorID
+      );
+      if (actor && actor instanceof NodeActor) {
+        selectedDOMNode = actor.rawNode;
+      }
+    }
+
+    Object.defineProperty(bindings, "$0", {
+      enumerable: true,
+      configurable: true,
+      get: () => {
+        if (selectedDOMNode && !Cu.isDeadWrapper(selectedDOMNode)) {
+          return dbgWindow.makeDebuggeeValue(selectedDOMNode);
+        }
+
+        return undefined;
+      },
+    });
+
+    // This function is used by 'eval' and 'reload' requests, but only 'eval'
+    // passes 'toolboxConsoleActor' from the client side in order to set
+    // the 'inspect' binding.
+    Object.defineProperty(bindings, "inspect", {
+      enumerable: true,
+      configurable: true,
+      value: dbgWindow.makeDebuggeeValue(object => {
+        const consoleActor = DevToolsServer.searchAllConnectionsForActor(
+          options.toolboxConsoleActorID
+        );
+        if (consoleActor) {
+          const dbgObj = consoleActor.makeDebuggeeValue(object);
+          consoleActor.inspectObject(
+            dbgObj,
+            "webextension-devtools-inspectedWindow-eval"
+          );
+        } else {
+          // TODO(rpl): evaluate if it would be better to raise an exception
+          // to the caller code instead.
+          console.error("Toolbox Console RDP Actor not found");
+        }
+      }),
+    });
+
+    return bindings;
+  }
+
+  /**
+   * Reload the target tab, optionally bypass cache, customize the userAgent and/or
+   * inject a script in targeted document or any of its sub-frame.
+   *
+   * @param {webExtensionCallerInfo} callerInfo
+   *   the addonId and the url (the addon base url or the url of the actual caller
+   *   filename and lineNumber) used to log useful debugging information in the
+   *   produced error logs and eval stack trace.
+   *
+   * @param {webExtensionReloadOptions} options
+   *   used to optionally enable the reload customizations.
+   * @param {boolean|undefined}       options.ignoreCache
+   *   enable/disable the cache bypass headers.
+   * @param {string|undefined}        options.userAgent
+   *   customize the userAgent during the page reload.
+   * @param {string|undefined}        options.injectedScript
+   *   evaluate the provided javascript code in the top level and every sub-frame
+   *   created during the page reload, before any other script in the page has been
+   *   executed.
+   */
+  async reload(callerInfo, { ignoreCache, userAgent, injectedScript }) {
+    if (isSystemPrincipalWindow(this.window)) {
+      console.error(
+        "Ignored inspectedWindow.reload on system principal target for " +
+          `${callerInfo.url}:${callerInfo.lineNumber}`
+      );
+      return {};
+    }
+
+    await new Promise(resolve => {
+      const delayedReload = () => {
+        // This won't work while the browser is shutting down and we don't really
+        // care.
+        if (Services.startup.shuttingDown) {
+          return;
+        }
+
+        if (injectedScript || userAgent) {
+          if (this.customizedReload) {
+            // TODO(rpl): check what chrome does, and evaluate if queue the new reload
+            // after the current one has been completed.
+            console.error(
+              "Reload already in progress. Ignored inspectedWindow.reload for " +
+                `${callerInfo.url}:${callerInfo.lineNumber}`
+            );
+            return;
+          }
+
+          try {
+            this.customizedReload = new CustomizedReload({
+              targetActor: this.targetActor,
+              inspectedWindowEval: this.eval.bind(this),
+              callerInfo,
+              injectedScript,
+              ignoreCache,
+            });
+
+            this.customizedReload
+              .start()
+              .catch(err => {
+                console.error(err);
+              })
+              .then(() => {
+                delete this.customizedReload;
+                resolve();
+              });
+          } catch (err) {
+            // Cancel the customized reload (if any) on exception during the
+            // reload setup.
+            if (this.customizedReload) {
+              this.customizedReload.stop(err);
+            }
+            throw err;
+          }
+        } else {
+          // If there is no custom user agent and/or injected script, then
+          // we can reload the target without subscribing any observer/listener.
+          let reloadFlags = Ci.nsIWebNavigation.LOAD_FLAGS_NONE;
+          if (ignoreCache) {
+            reloadFlags |= Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE;
+          }
+          this.webNavigation.reload(reloadFlags);
+          resolve();
+        }
+      };
+
+      // Execute the reload in a dispatched runnable, so that we can
+      // return the reply to the caller before the reload is actually
+      // started.
+      Services.tm.dispatchToMainThread(delayedReload);
+    });
+
+    return {};
+  }
+
+  /**
+   * Evaluate the provided javascript code in a target window (that is always the
+   * targetActor window when called through RDP protocol, or the passed
+   * customTargetWindow when called directly from the CustomizedReload instances).
+   *
+   * @param {webExtensionCallerInfo} callerInfo
+   *   the addonId and the url (the addon base url or the url of the actual caller
+   *   filename and lineNumber) used to log useful debugging information in the
+   *   produced error logs and eval stack trace.
+   *
+   * @param {string} expression
+   *   the javascript code to be evaluated in the target window
+   *
+   * @param {webExtensionEvalOptions} evalOptions
+   *   used to optionally enable the eval customizations.
+   *   NOTE: none of the eval options is currently implemented, they will be already
+   *   reported as unsupported by the WebExtensions schema validation wrappers, but
+   *   an additional level of error reporting is going to be applied here, so that
+   *   if the server and the client have different ideas of which option is supported
+   *   the eval call result will contain detailed informations (in the format usually
+   *   expected for errors not raised in the evaluated javascript code).
+   *
+   * @param {DOMWindow|undefined} customTargetWindow
+   *   Used in the CustomizedReload instances to evaluate the `injectedScript`
+   *   javascript code in every sub-frame of the target window during the tab reload.
+   *   NOTE: this parameter is not part of the RDP protocol exposed by this actor, when
+   *   it is called over the remote debugging protocol the target window is always
+   *   `targetActor.window`.
+   */
+  // eslint-disable-next-line complexity
+  eval(callerInfo, expression, options, customTargetWindow) {
+    const window = customTargetWindow || this.window;
+    options = options || {};
+
+    const extensionPolicy = WebExtensionPolicy.getByID(callerInfo.addonId);
+
+    if (!extensionPolicy) {
+      return createExceptionInfoResult({
+        description: "Inspector protocol error: %s %s",
+        details: ["Caller extension not found for", callerInfo.url],
+      });
+    }
+
+    if (!window) {
+      return createExceptionInfoResult({
+        description: "Inspector protocol error: %s",
+        details: [
+          "The target window is not defined. inspectedWindow.eval not executed.",
+        ],
+      });
+    }
+
+    if (
+      !extensionAllowedToInspectPrincipal(
+        extensionPolicy,
+        window.document.nodePrincipal
+      )
+    ) {
+      // Log the error for the user to know that the extension request has been
+      // denied (the extension may not warn the user at all).
+      logAccessDeniedWarning(window, callerInfo, extensionPolicy);
+
+      // The error message is generic here. If access is disallowed, we do not
+      // expose the URL either.
+      return createExceptionInfoResult({
+        description: "Inspector protocol error: %s",
+        details: [
+          "This extension is not allowed on the current inspected window origin",
+        ],
+      });
+    }
+
+    // Raise an error on the unsupported options.
+    if (
+      options.frameURL ||
+      options.contextSecurityOrigin ||
+      options.useContentScriptContext
+    ) {
+      return createExceptionInfoResult({
+        description: "Inspector protocol error: %s",
+        details: [
+          "The inspectedWindow.eval options are currently not supported",
+        ],
+      });
+    }
+
+    const dbgWindow = this.dbg.makeGlobalObjectReference(window);
+
+    let evalCalledFrom = callerInfo.url;
+    if (callerInfo.lineNumber) {
+      evalCalledFrom += `:${callerInfo.lineNumber}`;
+    }
+
+    const bindings = this.createEvalBindings(dbgWindow, options);
+
+    const result = dbgWindow.executeInGlobalWithBindings(expression, bindings, {
+      url: `debugger eval called from ${evalCalledFrom} - eval code`,
+    });
+
+    let evalResult;
+
+    if (result) {
+      if ("return" in result) {
+        evalResult = result.return;
+      } else if ("yield" in result) {
+        evalResult = result.yield;
+      } else if ("throw" in result) {
+        const throwErr = result.throw;
+
+        // XXXworkers: Calling unsafeDereference() returns an object with no
+        // toString method in workers. See Bug 1215120.
+        const unsafeDereference =
+          throwErr &&
+          typeof throwErr === "object" &&
+          throwErr.unsafeDereference();
+        const message = unsafeDereference?.toString
+          ? unsafeDereference.toString()
+          : String(throwErr);
+        const stack = unsafeDereference?.stack ? unsafeDereference.stack : null;
+
+        return {
+          exceptionInfo: {
+            isException: true,
+            value: `${message}\n\t${stack}`,
+          },
+        };
+      }
+    } else {
+      // TODO(rpl): can the result of executeInGlobalWithBinding be null or
+      // undefined? (which means that it is not a return, a yield or a throw).
+      console.error(
+        "Unexpected empty inspectedWindow.eval result for",
+        `${callerInfo.url}:${callerInfo.lineNumber}`
+      );
+    }
+
+    if (evalResult) {
+      try {
+        // Return the evalResult as a grip (used by the WebExtensions
+        // devtools inspector's sidebar.setExpression API method).
+        if (options.evalResultAsGrip) {
+          if (!options.toolboxConsoleActorID) {
+            return createExceptionInfoResult({
+              description: "Inspector protocol error: %s - %s",
+              details: [
+                "Unexpected invalid sidebar panel expression request",
+                "missing toolboxConsoleActorID",
+              ],
+            });
+          }
+
+          const consoleActor = DevToolsServer.searchAllConnectionsForActor(
+            options.toolboxConsoleActorID
+          );
+
+          return { valueGrip: consoleActor.createValueGrip(evalResult) };
+        }
+
+        if (evalResult && typeof evalResult === "object") {
+          evalResult = evalResult.unsafeDereference();
+        }
+        evalResult = JSON.parse(JSON.stringify(evalResult));
+      } catch (err) {
+        // The evaluation result cannot be sent over the RDP Protocol,
+        // report it as with the same data format used in the corresponding
+        // chrome API method.
+        return createExceptionInfoResult({
+          description: "Inspector protocol error: %s",
+          details: [String(err)],
+        });
+      }
+    }
+
+    return { value: evalResult };
+  }
+}
+
+exports.WebExtensionInspectedWindowActor = WebExtensionInspectedWindowActor;