void
AutoJSAPI::ReportException()
{
  MOZ_ASSERT(OwnsErrorReporting(), "This is not our exception to report!");
  if (!HasException()) {
    return;
  }

  // AutoJSAPI uses a JSAutoNullableCompartment, and may be in a null
  // compartment when the destructor is called. However, the JS engine
  // requires us to be in a compartment when we fetch the pending exception.
  // In this case, we enter the privileged junk scope and don't dispatch any
  // error events.
  JS::Rooted<JSObject*> errorGlobal(cx(), JS::CurrentGlobalOrNull(cx()));
  if (!errorGlobal) {
    if (mIsMainThread) {
      errorGlobal = xpc::PrivilegedJunkScope();
    } else {
      errorGlobal = workers::GetCurrentThreadWorkerGlobal();
    }
  }
  JSAutoCompartment ac(cx(), errorGlobal);
  JS::Rooted<JS::Value> exn(cx());
  js::ErrorReport jsReport(cx());
  if (StealException(&exn) && jsReport.init(cx(), exn)) {
    if (mIsMainThread) {
      RefPtr<xpc::ErrorReport> xpcReport = new xpc::ErrorReport();
      RefPtr<nsGlobalWindow> win = xpc::WindowGlobalOrNull(errorGlobal);
      nsPIDOMWindowInner* inner = win ? win->AsInner() : nullptr;
      xpcReport->Init(jsReport.report(), jsReport.message(),
                      nsContentUtils::IsCallerChrome(),
                      inner ? inner->WindowID() : 0);
      if (inner) {
        DispatchScriptErrorEvent(inner, JS_GetRuntime(cx()), xpcReport, exn);
      } else {
        xpcReport->LogToConsole();
      }
    } else {
      // On a worker, we just use the worker error reporting mechanism and don't
      // bother with xpc::ErrorReport.  This will ensure that all the right
      // events (which are a lot more complicated than in the window case) get
      // fired.
      workers::WorkerPrivate* worker = workers::GetCurrentThreadWorkerPrivate();
      MOZ_ASSERT(worker);
      MOZ_ASSERT(worker->GetJSContext() == cx());
      // Before invoking ReportError, put the exception back on the context,
      // because it may want to put it in its error events and has no other way
      // to get hold of it.  After we invoke ReportError, clear the exception on
      // cx(), just in case ReportError didn't.
      JS_SetPendingException(cx(), exn);
      worker->ReportError(cx(), jsReport.message(), jsReport.report());
      ClearException();
    }
  } else {
    NS_WARNING("OOMed while acquiring uncaught exception from JSAPI");
    ClearException();
  }
}
Example #2
0
NS_IMETHODIMP
PostMessageEvent::Run()
{
  MOZ_ASSERT(mTargetWindow->IsOuterWindow(),
             "should have been passed an outer window!");
  MOZ_ASSERT(!mSource || mSource->IsOuterWindow(),
             "should have been passed an outer window!");

  AutoJSAPI jsapi;
  jsapi.Init();
  JSContext* cx = jsapi.cx();

  // The document is just used for the principal mismatch error message below.
  // Use a stack variable so mSourceDocument is not held onto after this method
  // finishes, regardless of the method outcome.
  nsCOMPtr<nsIDocument> sourceDocument;
  sourceDocument.swap(mSourceDocument);

  // If we bailed before this point we're going to leak mMessage, but
  // that's probably better than crashing.

  RefPtr<nsGlobalWindow> targetWindow;
  if (mTargetWindow->IsClosedOrClosing() ||
      !(targetWindow = mTargetWindow->GetCurrentInnerWindowInternal()) ||
      targetWindow->IsClosedOrClosing())
    return NS_OK;

  MOZ_ASSERT(targetWindow->IsInnerWindow(),
             "we ordered an inner window!");
  JSAutoCompartment ac(cx, targetWindow->GetWrapperPreserveColor());

  // Ensure that any origin which might have been provided is the origin of this
  // window's document.  Note that we do this *now* instead of when postMessage
  // is called because the target window might have been navigated to a
  // different location between then and now.  If this check happened when
  // postMessage was called, it would be fairly easy for a malicious webpage to
  // intercept messages intended for another site by carefully timing navigation
  // of the target window so it changed location after postMessage but before
  // now.
  if (mProvidedPrincipal) {
    // Get the target's origin either from its principal or, in the case the
    // principal doesn't carry a URI (e.g. the system principal), the target's
    // document.
    nsIPrincipal* targetPrin = targetWindow->GetPrincipal();
    if (NS_WARN_IF(!targetPrin))
      return NS_OK;

    // Note: This is contrary to the spec with respect to file: URLs, which
    //       the spec groups into a single origin, but given we intentionally
    //       don't do that in other places it seems better to hold the line for
    //       now.  Long-term, we want HTML5 to address this so that we can
    //       be compliant while being safer.
    if (!targetPrin->Equals(mProvidedPrincipal)) {
      nsAutoString providedOrigin, targetOrigin;
      nsresult rv = nsContentUtils::GetUTFOrigin(targetPrin, targetOrigin);
      NS_ENSURE_SUCCESS(rv, rv);
      rv = nsContentUtils::GetUTFOrigin(mProvidedPrincipal, providedOrigin);
      NS_ENSURE_SUCCESS(rv, rv);

      const char16_t* params[] = { providedOrigin.get(), targetOrigin.get() };

      nsContentUtils::ReportToConsole(nsIScriptError::errorFlag,
        NS_LITERAL_CSTRING("DOM Window"), sourceDocument,
        nsContentUtils::eDOM_PROPERTIES,
        "TargetPrincipalDoesNotMatch",
        params, ArrayLength(params));

      return NS_OK;
    }
  }

  ErrorResult rv;
  JS::Rooted<JS::Value> messageData(cx);
  nsCOMPtr<nsPIDOMWindowInner> window = targetWindow->AsInner();

  Read(window, cx, &messageData, rv);
  if (NS_WARN_IF(rv.Failed())) {
    return rv.StealNSResult();
  }

  // Create the event
  nsCOMPtr<mozilla::dom::EventTarget> eventTarget = do_QueryObject(targetWindow);
  RefPtr<MessageEvent> event =
    new MessageEvent(eventTarget, nullptr, nullptr);


  Nullable<WindowProxyOrMessagePort> source;
  source.SetValue().SetAsWindowProxy() = mSource ? mSource->AsOuter() : nullptr;

  event->InitMessageEvent(nullptr, NS_LITERAL_STRING("message"),
                          false /*non-bubbling */, false /*cancelable */,
                          messageData, mCallerOrigin,
                          EmptyString(), source, nullptr);

  nsTArray<RefPtr<MessagePort>> ports = TakeTransferredPorts();

  event->SetPorts(new MessagePortList(static_cast<dom::Event*>(event.get()),
                                      ports));

  // We can't simply call dispatchEvent on the window because doing so ends
  // up flipping the trusted bit on the event, and we don't want that to
  // happen because then untrusted content can call postMessage on a chrome
  // window if it can get a reference to it.

  nsIPresShell *shell = targetWindow->GetExtantDoc()->GetShell();
  RefPtr<nsPresContext> presContext;
  if (shell)
    presContext = shell->GetPresContext();

  event->SetTrusted(mTrustedCaller);
  WidgetEvent* internalEvent = event->GetInternalNSEvent();

  nsEventStatus status = nsEventStatus_eIgnore;
  EventDispatcher::Dispatch(window,
                            presContext,
                            internalEvent,
                            static_cast<dom::Event*>(event.get()),
                            &status);
  return NS_OK;
}
void
AutoJSAPI::ReportException()
{
  if (!HasException()) {
    return;
  }

  // AutoJSAPI uses a JSAutoNullableCompartment, and may be in a null
  // compartment when the destructor is called. However, the JS engine
  // requires us to be in a compartment when we fetch the pending exception.
  // In this case, we enter the privileged junk scope and don't dispatch any
  // error events.
  JS::Rooted<JSObject*> errorGlobal(cx(), JS::CurrentGlobalOrNull(cx()));
  if (!errorGlobal) {
    if (mIsMainThread) {
      errorGlobal = xpc::PrivilegedJunkScope();
    } else {
      errorGlobal = workers::GetCurrentThreadWorkerGlobal();
    }
  }
  JSAutoCompartment ac(cx(), errorGlobal);
  JS::Rooted<JS::Value> exn(cx());
  js::ErrorReport jsReport(cx());
  if (StealException(&exn) &&
      jsReport.init(cx(), exn, js::ErrorReport::WithSideEffects)) {
    if (mIsMainThread) {
      RefPtr<xpc::ErrorReport> xpcReport = new xpc::ErrorReport();

      RefPtr<nsGlobalWindow> win = xpc::WindowGlobalOrNull(errorGlobal);
      if (!win) {
        // We run addons in a separate privileged compartment, but they still
        // expect to trigger the onerror handler of their associated DOM Window.
        win = xpc::AddonWindowOrNull(errorGlobal);
      }
      nsPIDOMWindowInner* inner = win ? win->AsInner() : nullptr;
      xpcReport->Init(jsReport.report(), jsReport.toStringResult().c_str(),
                      nsContentUtils::IsCallerChrome(),
                      inner ? inner->WindowID() : 0);
      if (inner && jsReport.report()->errorNumber != JSMSG_OUT_OF_MEMORY) {
        JS::RootingContext* rcx = JS::RootingContext::get(cx());
        DispatchScriptErrorEvent(inner, rcx, xpcReport, exn);
      } else {
        JS::Rooted<JSObject*> stack(cx(),
          xpc::FindExceptionStackForConsoleReport(inner, exn));
        xpcReport->LogToConsoleWithStack(stack);
      }
    } else {
      // On a worker, we just use the worker error reporting mechanism and don't
      // bother with xpc::ErrorReport.  This will ensure that all the right
      // events (which are a lot more complicated than in the window case) get
      // fired.
      workers::WorkerPrivate* worker = workers::GetCurrentThreadWorkerPrivate();
      MOZ_ASSERT(worker);
      MOZ_ASSERT(worker->GetJSContext() == cx());
      // Before invoking ReportError, put the exception back on the context,
      // because it may want to put it in its error events and has no other way
      // to get hold of it.  After we invoke ReportError, clear the exception on
      // cx(), just in case ReportError didn't.
      JS_SetPendingException(cx(), exn);
      worker->ReportError(cx(), jsReport.toStringResult(), jsReport.report());
      ClearException();
    }
  } else {
    NS_WARNING("OOMed while acquiring uncaught exception from JSAPI");
    ClearException();
  }
}