/* -*- Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 8 -*- */
/* vim: set sw=4 ts=8 et tw=80 ft=cpp : */
/* 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 protocol PBrowser;
include PBrowserOrId;

using mozilla::layout::ScrollingBehavior from "mozilla/layout/RenderFrameUtils.h";

namespace mozilla {
namespace dom {

// An IPCTabContext which corresponds to a PBrowser opened by a child when it
// receives window.open().
//
// If isBrowserElement is false, this PopupIPCTabContext corresponds to an app
// frame, and the frame's app-id and app-frame-owner-app-id will be equal to the
// opener's values.
//
// If isBrowserElement is true, the frame's browserFrameOwnerAppId will be equal
// to the opener's app-id.
//
// It's an error to set isBrowserElement == false if opener is a browser
// element.  Such a PopupIPCTabContext should be rejected by code which receives
// it.
struct PopupIPCTabContext
{
  PBrowserOrId opener;
  bool isBrowserElement;
};

// An IPCTabContext which corresponds to an app frame.
struct AppFrameIPCTabContext
{
  // The ID of the app this frame corresponds to.  May be NO_APP_ID.
  uint32_t ownAppId;

  // The ID of the app containing this frame.  May be NO_APP_ID.
  uint32_t appFrameOwnerAppId;
};

// An IPCTabContext which corresponds to a browser frame.
struct BrowserFrameIPCTabContext
{
  // The ID of the app which contains this browser frame.  May be NO_APP_ID.
  uint32_t browserFrameOwnerAppId;
};

// This is equivalent to AppFrameIPCTabContext with all fields set to NO_APP_ID.
struct VanillaFrameIPCTabContext
{};

// IPCTabContext is an analog to mozilla::dom::TabContext.  Both specify an
// iframe/PBrowser's own and containing app-ids and tell you whether the
// iframe/PBrowser is a browser frame.  But only IPCTabContext is allowed to
// travel over IPC.
//
// We need IPCTabContext (specifically, PopupIPCTabContext) to prevent a
// privilege escalation attack by a compromised child process.  See the comment
// on AllocPBrowser for details.
union IPCTabAppBrowserContext
{
  PopupIPCTabContext;
  AppFrameIPCTabContext;
  BrowserFrameIPCTabContext;
  VanillaFrameIPCTabContext;
};

struct IPCTabContext {
  IPCTabAppBrowserContext appBrowserContext;
  ScrollingBehavior scrollingBehavior;
};

}
}