1 files changed, 422 insertions, 0 deletions
diff --git a/dom/events/KeyboardEvent.cpp b/dom/events/KeyboardEvent.cpp
new file mode 100644
index 0000000000..2b70c84c6a
--- /dev/null
+++ b/dom/events/KeyboardEvent.cpp
@@ -0,0 +1,422 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#include "mozilla/dom/KeyboardEvent.h"
+
+#include "mozilla/BasicEvents.h"
+#include "mozilla/StaticPrefs_dom.h"
+#include "mozilla/TextEvents.h"
+#include "mozilla/dom/Document.h"
+#include "mozilla/LookAndFeel.h"
+#include "nsContentUtils.h"
+#include "nsIPrincipal.h"
+#include "nsRFPService.h"
+#include "prtime.h"
+
+namespace mozilla::dom {
+
+KeyboardEvent::KeyboardEvent(EventTarget* aOwner, nsPresContext* aPresContext,
+                             WidgetKeyboardEvent* aEvent)
+    : UIEvent(aOwner, aPresContext,
+              aEvent ? aEvent
+                     : new WidgetKeyboardEvent(false, eVoidEvent, nullptr)),
+      mInitializedByJS(false),
+      mInitializedByCtor(false),
+      mInitializedWhichValue(0) {
+  if (aEvent) {
+    mEventIsInternal = false;
+  } else {
+    mEventIsInternal = true;
+    mEvent->AsKeyboardEvent()->mKeyNameIndex = KEY_NAME_INDEX_USE_STRING;
+  }
+}
+
+bool KeyboardEvent::IsMenuAccessKeyPressed() const {
+  Modifiers mask = LookAndFeel::GetMenuAccessKeyModifiers();
+  Modifiers modifiers = GetModifiersForMenuAccessKey();
+  return mask != MODIFIER_SHIFT && (modifiers & mask) &&
+         (modifiers & ~(mask | MODIFIER_SHIFT)) == 0;
+}
+
+static constexpr Modifiers kPossibleModifiersForAccessKey =
+    MODIFIER_SHIFT | MODIFIER_CONTROL | MODIFIER_ALT | MODIFIER_META;
+
+Modifiers KeyboardEvent::GetModifiersForMenuAccessKey() const {
+  const WidgetInputEvent* inputEvent = WidgetEventPtr()->AsInputEvent();
+  MOZ_ASSERT(inputEvent);
+  return inputEvent->mModifiers & kPossibleModifiersForAccessKey;
+}
+
+bool KeyboardEvent::AltKey(CallerType aCallerType) {
+  bool altState = mEvent->AsKeyboardEvent()->IsAlt();
+
+  if (!ShouldResistFingerprinting(aCallerType)) {
+    return altState;
+  }
+
+  // We need to give a spoofed state for Alt key since it could be used as a
+  // modifier key in certain keyboard layout. For example, the '@' key for
+  // German keyboard for MAC is Alt+L.
+  return GetSpoofedModifierStates(Modifier::MODIFIER_ALT, altState);
+}
+
+bool KeyboardEvent::CtrlKey(CallerType aCallerType) {
+  // We don't spoof this key when privacy.resistFingerprinting
+  // is enabled, because it is often used for command key
+  // combinations in web apps.
+  return mEvent->AsKeyboardEvent()->IsControl();
+}
+
+bool KeyboardEvent::ShiftKey(CallerType aCallerType) {
+  bool shiftState = mEvent->AsKeyboardEvent()->IsShift();
+
+  if (!ShouldResistFingerprinting(aCallerType)) {
+    return shiftState;
+  }
+
+  return GetSpoofedModifierStates(Modifier::MODIFIER_SHIFT, shiftState);
+}
+
+bool KeyboardEvent::MetaKey() {
+  // We don't spoof this key when privacy.resistFingerprinting
+  // is enabled, because it is often used for command key
+  // combinations in web apps.
+  return mEvent->AsKeyboardEvent()->IsMeta();
+}
+
+bool KeyboardEvent::Repeat() { return mEvent->AsKeyboardEvent()->mIsRepeat; }
+
+bool KeyboardEvent::IsComposing() {
+  return mEvent->AsKeyboardEvent()->mIsComposing;
+}
+
+void KeyboardEvent::GetKey(nsAString& aKeyName) const {
+  mEvent->AsKeyboardEvent()->GetDOMKeyName(aKeyName);
+}
+
+void KeyboardEvent::GetCode(nsAString& aCodeName, CallerType aCallerType) {
+  if (!ShouldResistFingerprinting(aCallerType)) {
+    mEvent->AsKeyboardEvent()->GetDOMCodeName(aCodeName);
+    return;
+  }
+
+  // When fingerprinting resistance is enabled, we will give a spoofed code
+  // according to the content-language of the document.
+  nsCOMPtr<Document> doc = GetDocument();
+
+  nsRFPService::GetSpoofedCode(doc, mEvent->AsKeyboardEvent(), aCodeName);
+}
+
+void KeyboardEvent::GetInitDict(KeyboardEventInit& aParam) {
+  GetKey(aParam.mKey);
+  GetCode(aParam.mCode);
+  aParam.mLocation = Location();
+  aParam.mRepeat = Repeat();
+  aParam.mIsComposing = IsComposing();
+
+  // legacy attributes
+  aParam.mKeyCode = KeyCode();
+  aParam.mCharCode = CharCode();
+  aParam.mWhich = Which();
+
+  // modifiers from EventModifierInit
+  aParam.mCtrlKey = CtrlKey();
+  aParam.mShiftKey = ShiftKey();
+  aParam.mAltKey = AltKey();
+  aParam.mMetaKey = MetaKey();
+
+  WidgetKeyboardEvent* internalEvent = mEvent->AsKeyboardEvent();
+  aParam.mModifierAltGraph = internalEvent->IsAltGraph();
+  aParam.mModifierCapsLock = internalEvent->IsCapsLocked();
+  aParam.mModifierFn = internalEvent->IsFn();
+  aParam.mModifierFnLock = internalEvent->IsFnLocked();
+  aParam.mModifierNumLock = internalEvent->IsNumLocked();
+  aParam.mModifierScrollLock = internalEvent->IsScrollLocked();
+  aParam.mModifierSymbol = internalEvent->IsSymbol();
+  aParam.mModifierSymbolLock = internalEvent->IsSymbolLocked();
+
+  // EventInit
+  aParam.mBubbles = internalEvent->mFlags.mBubbles;
+  aParam.mCancelable = internalEvent->mFlags.mCancelable;
+}
+
+bool KeyboardEvent::ShouldUseSameValueForCharCodeAndKeyCode(
+    const WidgetKeyboardEvent& aWidgetKeyboardEvent,
+    CallerType aCallerType) const {
+  // - If this event is initialized by JS, we don't need to return same value
+  //   for keyCode and charCode since they can be initialized separately.
+  // - If this is not a keypress event, we shouldn't return same value for
+  //   keyCode and charCode.
+  // - If we need to return legacy keyCode and charCode values for the web
+  //   app due to in the blacklist.
+  // - If this event is referred by default handler, i.e., the caller is
+  //   system or this event is now in the system group, we don't need to use
+  //   hack for web-compat.
+  if (mInitializedByJS || aWidgetKeyboardEvent.mMessage != eKeyPress ||
+      aWidgetKeyboardEvent.mUseLegacyKeyCodeAndCharCodeValues ||
+      aCallerType == CallerType::System ||
+      aWidgetKeyboardEvent.mFlags.mInSystemGroup) {
+    return false;
+  }
+
+  MOZ_ASSERT(aCallerType == CallerType::NonSystem);
+
+  return StaticPrefs::
+      dom_keyboardevent_keypress_set_keycode_and_charcode_to_same_value();
+}
+
+uint32_t KeyboardEvent::CharCode(CallerType aCallerType) {
+  WidgetKeyboardEvent* widgetKeyboardEvent = mEvent->AsKeyboardEvent();
+  if (mInitializedByJS) {
+    // If this is initialized by Ctor, we should return the initialized value.
+    if (mInitializedByCtor) {
+      return widgetKeyboardEvent->mCharCode;
+    }
+    // Otherwise, i.e., initialized by InitKey*Event(), we should return the
+    // initialized value only when eKeyPress or eAccessKeyNotFound event.
+    // Although this is odd, but our traditional behavior.
+    return widgetKeyboardEvent->mMessage == eKeyPress ||
+                   widgetKeyboardEvent->mMessage == eAccessKeyNotFound
+               ? widgetKeyboardEvent->mCharCode
+               : 0;
+  }
+
+  // If the key is a function key, we should return the result of KeyCode()
+  // even from CharCode().  Otherwise, i.e., the key may be a printable
+  // key or actually a printable key, we should return the given charCode
+  // value.
+
+  if (widgetKeyboardEvent->mKeyNameIndex != KEY_NAME_INDEX_USE_STRING &&
+      ShouldUseSameValueForCharCodeAndKeyCode(*widgetKeyboardEvent,
+                                              aCallerType)) {
+    return ComputeTraditionalKeyCode(*widgetKeyboardEvent, aCallerType);
+  }
+
+  return widgetKeyboardEvent->mCharCode;
+}
+
+uint32_t KeyboardEvent::KeyCode(CallerType aCallerType) {
+  WidgetKeyboardEvent* widgetKeyboardEvent = mEvent->AsKeyboardEvent();
+  if (mInitializedByJS) {
+    // If this is initialized by Ctor, we should return the initialized value.
+    if (mInitializedByCtor) {
+      return widgetKeyboardEvent->mKeyCode;
+    }
+    // Otherwise, i.e., initialized by InitKey*Event(), we should return the
+    // initialized value only when the event message is a valid keyboard event
+    // message.  Although this is odd, but our traditional behavior.
+    // NOTE: The fix of bug 1222285 changed the behavior temporarily if
+    //       spoofing is enabled.  However, the behavior does not make sense
+    //       since if the event is generated by JS, the behavior shouldn't
+    //       be changed by whether spoofing is enabled or not.  Therefore,
+    //       we take back the original behavior.
+    return widgetKeyboardEvent->HasKeyEventMessage()
+               ? widgetKeyboardEvent->mKeyCode
+               : 0;
+  }
+
+  // If the key is not a function key, i.e., the key may be a printable key
+  // or a function key mapped as a printable key, we should use charCode value
+  // for keyCode value if this is a "keypress" event.
+
+  if (widgetKeyboardEvent->mKeyNameIndex == KEY_NAME_INDEX_USE_STRING &&
+      ShouldUseSameValueForCharCodeAndKeyCode(*widgetKeyboardEvent,
+                                              aCallerType)) {
+    return widgetKeyboardEvent->mCharCode;
+  }
+
+  return ComputeTraditionalKeyCode(*widgetKeyboardEvent, aCallerType);
+}
+
+uint32_t KeyboardEvent::ComputeTraditionalKeyCode(
+    WidgetKeyboardEvent& aKeyboardEvent, CallerType aCallerType) {
+  if (!ShouldResistFingerprinting(aCallerType)) {
+    return aKeyboardEvent.mKeyCode;
+  }
+
+  // In Netscape style (i.e., traditional behavior of Gecko), the keyCode
+  // should be zero if the char code is given.
+  if ((mEvent->mMessage == eKeyPress ||
+       mEvent->mMessage == eAccessKeyNotFound) &&
+      aKeyboardEvent.mCharCode) {
+    return 0;
+  }
+
+  // When fingerprinting resistance is enabled, we will give a spoofed keyCode
+  // according to the content-language of the document.
+  nsCOMPtr<Document> doc = GetDocument();
+  uint32_t spoofedKeyCode;
+
+  if (nsRFPService::GetSpoofedKeyCode(doc, &aKeyboardEvent, spoofedKeyCode)) {
+    return spoofedKeyCode;
+  }
+
+  return 0;
+}
+
+uint32_t KeyboardEvent::Which(CallerType aCallerType) {
+  // If this event is initialized with ctor, which can have independent value.
+  if (mInitializedByCtor) {
+    return mInitializedWhichValue;
+  }
+
+  switch (mEvent->mMessage) {
+    case eKeyDown:
+    case eKeyUp:
+      return KeyCode(aCallerType);
+    case eKeyPress:
+      // Special case for 4xp bug 62878.  Try to make value of which
+      // more closely mirror the values that 4.x gave for RETURN and BACKSPACE
+      {
+        uint32_t keyCode = mEvent->AsKeyboardEvent()->mKeyCode;
+        if (keyCode == NS_VK_RETURN || keyCode == NS_VK_BACK) {
+          return keyCode;
+        }
+        return CharCode();
+      }
+    default:
+      break;
+  }
+
+  return 0;
+}
+
+uint32_t KeyboardEvent::Location() {
+  return mEvent->AsKeyboardEvent()->mLocation;
+}
+
+// static
+already_AddRefed<KeyboardEvent> KeyboardEvent::ConstructorJS(
+    const GlobalObject& aGlobal, const nsAString& aType,
+    const KeyboardEventInit& aParam) {
+  nsCOMPtr<EventTarget> target = do_QueryInterface(aGlobal.GetAsSupports());
+  RefPtr<KeyboardEvent> newEvent = new KeyboardEvent(target, nullptr, nullptr);
+  newEvent->InitWithKeyboardEventInit(target, aType, aParam);
+
+  return newEvent.forget();
+}
+
+void KeyboardEvent::InitWithKeyboardEventInit(EventTarget* aOwner,
+                                              const nsAString& aType,
+                                              const KeyboardEventInit& aParam) {
+  bool trusted = Init(aOwner);
+  InitKeyEventJS(aType, aParam.mBubbles, aParam.mCancelable, aParam.mView,
+                 false, false, false, false, aParam.mKeyCode, aParam.mCharCode);
+  InitModifiers(aParam);
+  SetTrusted(trusted);
+  mDetail = aParam.mDetail;
+  mInitializedByJS = true;
+  mInitializedByCtor = true;
+  mInitializedWhichValue = aParam.mWhich;
+
+  WidgetKeyboardEvent* internalEvent = mEvent->AsKeyboardEvent();
+  internalEvent->mLocation = aParam.mLocation;
+  internalEvent->mIsRepeat = aParam.mRepeat;
+  internalEvent->mIsComposing = aParam.mIsComposing;
+  internalEvent->mKeyNameIndex =
+      WidgetKeyboardEvent::GetKeyNameIndex(aParam.mKey);
+  if (internalEvent->mKeyNameIndex == KEY_NAME_INDEX_USE_STRING) {
+    internalEvent->mKeyValue = aParam.mKey;
+  }
+  internalEvent->mCodeNameIndex =
+      WidgetKeyboardEvent::GetCodeNameIndex(aParam.mCode);
+  if (internalEvent->mCodeNameIndex == CODE_NAME_INDEX_USE_STRING) {
+    internalEvent->mCodeValue = aParam.mCode;
+  }
+}
+
+// static
+bool KeyboardEvent::IsInitKeyEventAvailable(JSContext* aCx, JSObject*) {
+  if (StaticPrefs::dom_keyboardevent_init_key_event_enabled()) {
+    return true;
+  }
+  if (!StaticPrefs::dom_keyboardevent_init_key_event_enabled_in_addons()) {
+    return false;
+  }
+  nsIPrincipal* principal = nsContentUtils::SubjectPrincipal(aCx);
+  return principal && principal->GetIsAddonOrExpandedAddonPrincipal();
+}
+
+void KeyboardEvent::InitKeyEventJS(const nsAString& aType, bool aCanBubble,
+                                   bool aCancelable, nsGlobalWindowInner* aView,
+                                   bool aCtrlKey, bool aAltKey, bool aShiftKey,
+                                   bool aMetaKey, uint32_t aKeyCode,
+                                   uint32_t aCharCode) {
+  NS_ENSURE_TRUE_VOID(!mEvent->mFlags.mIsBeingDispatched);
+  mInitializedByJS = true;
+  mInitializedByCtor = false;
+
+  UIEvent::InitUIEvent(aType, aCanBubble, aCancelable, aView, 0);
+
+  WidgetKeyboardEvent* keyEvent = mEvent->AsKeyboardEvent();
+  keyEvent->InitBasicModifiers(aCtrlKey, aAltKey, aShiftKey, aMetaKey);
+  keyEvent->mKeyCode = aKeyCode;
+  keyEvent->mCharCode = aCharCode;
+}
+
+void KeyboardEvent::InitKeyboardEventJS(
+    const nsAString& aType, bool aCanBubble, bool aCancelable,
+    nsGlobalWindowInner* aView, const nsAString& aKey, uint32_t aLocation,
+    bool aCtrlKey, bool aAltKey, bool aShiftKey, bool aMetaKey) {
+  NS_ENSURE_TRUE_VOID(!mEvent->mFlags.mIsBeingDispatched);
+  mInitializedByJS = true;
+  mInitializedByCtor = false;
+
+  UIEvent::InitUIEvent(aType, aCanBubble, aCancelable, aView, 0);
+
+  WidgetKeyboardEvent* keyEvent = mEvent->AsKeyboardEvent();
+  keyEvent->InitBasicModifiers(aCtrlKey, aAltKey, aShiftKey, aMetaKey);
+  keyEvent->mLocation = aLocation;
+  keyEvent->mKeyNameIndex = KEY_NAME_INDEX_USE_STRING;
+  keyEvent->mKeyValue = aKey;
+}
+
+bool KeyboardEvent::ShouldResistFingerprinting(CallerType aCallerType) {
+  // There are five situations we don't need to spoof this keyboard event.
+  //   1. The pref privcy.resistFingerprinting' is false, we fast return here.
+  //   2. This event is initialized by scripts.
+  //   3. This event is from Numpad.
+  //   4. This event is in the system group.
+  //   5. The caller type is system.
+  if (!nsContentUtils::ShouldResistFingerprinting("Efficiency Check",
+                                                  RFPTarget::KeyboardEvents) ||
+      mInitializedByJS || aCallerType == CallerType::System ||
+      mEvent->mFlags.mInSystemGroup ||
+      mEvent->AsKeyboardEvent()->mLocation ==
+          KeyboardEvent_Binding::DOM_KEY_LOCATION_NUMPAD) {
+    return false;
+  }
+
+  nsCOMPtr<Document> doc = GetDocument();
+  // We've checked the pref above, so use true as fallback if doc is null.
+  return doc ? doc->ShouldResistFingerprinting(RFPTarget::KeyboardEvents)
+             : true;
+}
+
+bool KeyboardEvent::GetSpoofedModifierStates(const Modifiers aModifierKey,
+                                             const bool aRawModifierState) {
+  bool spoofedState;
+  nsCOMPtr<Document> doc = GetDocument();
+
+  if (nsRFPService::GetSpoofedModifierStates(doc, mEvent->AsKeyboardEvent(),
+                                             aModifierKey, spoofedState)) {
+    return spoofedState;
+  }
+
+  return aRawModifierState;
+}
+
+}  // namespace mozilla::dom
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+already_AddRefed<KeyboardEvent> NS_NewDOMKeyboardEvent(
+    EventTarget* aOwner, nsPresContext* aPresContext,
+    WidgetKeyboardEvent* aEvent) {
+  RefPtr<KeyboardEvent> it = new KeyboardEvent(aOwner, aPresContext, aEvent);
+  return it.forget();
+}