blob: ff0ce91a851950d54fbeee15fe3e4fe64c550c9d [file] [log] [blame]
// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <stdint.h>
#include "base/process/process_handle.h"
#include "ipc/brokerable_attachment.h"
#include "ipc/handle_win.h"
#include "ipc/ipc_export.h"
namespace IPC {
namespace internal {
// This class represents a Windows HANDLE attached to a Chrome IPC message.
class IPC_EXPORT HandleAttachmentWin : public BrokerableAttachment {
// The wire format for this handle.
struct IPC_EXPORT WireFormat {
// IPC translation requires that classes passed through IPC have a default
// constructor.
: handle(0),
permissions(HandleWin::INVALID) {}
WireFormat(int32_t handle,
const base::ProcessId& destination_process,
HandleWin::Permissions permissions,
const AttachmentId& attachment_id)
: handle(handle),
attachment_id(attachment_id) {}
// The HANDLE that is intended for duplication, or the HANDLE that has been
// duplicated, depending on context.
// The type is int32_t instead of HANDLE because HANDLE gets typedefed to
// void*, whose size varies between 32 and 64-bit processes. Using a
// int32_t means that 64-bit processes will need to perform both up-casting
// and down-casting. This is performed using the appropriate Windows APIs.
// A value of 0 is equivalent to an invalid handle.
int32_t handle;
// The id of the destination process that the handle is duplicated into.
base::ProcessId destination_process;
// The permissions to use when duplicating the handle.
HandleWin::Permissions permissions;
AttachmentId attachment_id;
// This constructor makes a copy of |handle| and takes ownership of the
// result. Should only be called by the sender of a Chrome IPC message.
HandleAttachmentWin(const HANDLE& handle, HandleWin::Permissions permissions);
enum FromWire {
// This constructor takes ownership of |handle|. Should only be called by the
// receiver of a Chrome IPC message.
HandleAttachmentWin(const HANDLE& handle, FromWire from_wire);
// This constructor takes ownership of |wire_format.handle| without making a
// copy. Should only be called by the receiver of a Chrome IPC message.
explicit HandleAttachmentWin(const WireFormat& wire_format);
BrokerableType GetBrokerableType() const override;
// Returns the wire format of this attachment.
WireFormat GetWireFormat(const base::ProcessId& destination) const;
HANDLE get_handle() const { return handle_; }
// The caller of this method has taken ownership of |handle_|.
void reset_handle_ownership() {
owns_handle_ = false;
~HandleAttachmentWin() override;
HANDLE handle_;
HandleWin::Permissions permissions_;
// In the sender process, the attachment owns the HANDLE of a newly created
// message. The attachment broker will eventually take ownership, and set
// this member to |false|.
// In the destination process, the attachment owns the Mach port until a call
// to ParamTraits<HandleWin>::Read() takes ownership.
bool owns_handle_;
} // namespace internal
} // namespace IPC