// Copyright (c) 2012 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.

#ifndef CHROMEOS_DBUS_PERMISSION_BROKER_CLIENT_H_
#define CHROMEOS_DBUS_PERMISSION_BROKER_CLIENT_H_

#include <string>

#include "base/basictypes.h"
#include "base/callback.h"
#include "chromeos/chromeos_export.h"
#include "chromeos/dbus/dbus_client.h"
#include "dbus/file_descriptor.h"

namespace chromeos {

// PermissionBrokerClient is used to communicate with the permission broker, a
// process that allows requesting permission to access specific device nodes.
// For example, one place that this client is used is within the USB extension
// API code, where it is used to request explicit access to USB peripherals
// which the user the browser runs under normally wouldn't have access to. For
// more details on the permission broker see:
// http://git.chromium.org/gitweb/?p=chromiumos/platform/permission_broker.git
class CHROMEOS_EXPORT PermissionBrokerClient : public DBusClient {
 public:
  // The ResultCallback is used for both the RequestPathAccess and
  // RequestUsbAccess methods. Its boolean parameter represents the result of
  // the operation that it was submitted alongside.
  typedef base::Callback<void(bool)> ResultCallback;

  // An OpenPathCallback callback is run when an OpenPath request is completed.
  typedef base::Callback<void(dbus::FileDescriptor)> OpenPathCallback;

  ~PermissionBrokerClient() override;

  static PermissionBrokerClient* Create();

  // CheckPathAccess requests a hint from the permission broker about whether
  // a later call to RequestPathAccess will be successful. It presumes that
  // the |interface_id| value passed to RequestPathAccess will be
  // UsbDevicePermissionsData::ANY_INTERFACE).
  virtual void CheckPathAccess(const std::string& path,
                               const ResultCallback& callback) = 0;

  // RequestPathAccess requests access to a single device node identified by
  // |path|. If |interface_id| value is passed (different than
  // UsbDevicePermissionData::ANY_INTERFACE), the request will check if a
  // specific interface is claimed while requesting access.
  // This allows devices with multiple interfaces to be accessed even if
  // some of them are already claimed by kernel.
  virtual void RequestPathAccess(const std::string& path,
                                 int interface_id,
                                 const ResultCallback& callback) = 0;

  // OpenPath requests that the permission broker open the device node
  // identified by |path| and return the resulting file descriptor.
  virtual void OpenPath(const std::string& path,
                        const OpenPathCallback& callback) = 0;

  // Requests the |port| be opened on the firewall for incoming TCP/IP
  // connections received on |interface| (an empty string indicates all
  // interfaces). An open pipe must be passed as |lifeline_fd| so that the
  // permission broker can monitor the lifetime of the calling process.
  virtual void RequestTcpPortAccess(uint16 port,
                                    const std::string& interface,
                                    const dbus::FileDescriptor& lifeline_fd,
                                    const ResultCallback& callback) = 0;

  // Requests the |port| be opened on the firewall for incoming UDP packets
  // received on |interface| (an empty string indicates all interfaces). An open
  // pipe must be passed as |lifeline_fd| so that the permission broker can
  // monitor the lifetime of the calling process.
  virtual void RequestUdpPortAccess(uint16 port,
                                    const std::string& interface,
                                    const dbus::FileDescriptor& lifeline_fd,
                                    const ResultCallback& callback) = 0;

  // Releases a request for an open firewall port for TCP/IP connections. The
  // |port| and |interface| parameters must be the same as a previous call to
  // RequestTcpPortAccess.
  virtual void ReleaseTcpPort(uint16 port,
                              const std::string& interface,
                              const ResultCallback& callback) = 0;

  // Releases a request for an open firewall port for UDP packets. The |port|
  // and |interface| parameters must be the same as a previous call to
  // RequestUdpPortAccess.
  virtual void ReleaseUdpPort(uint16 port,
                              const std::string& interface,
                              const ResultCallback& callback) = 0;

 protected:
  PermissionBrokerClient();

 private:
  DISALLOW_COPY_AND_ASSIGN(PermissionBrokerClient);
};

}  // namespace chromeos

#endif  // CHROMEOS_DBUS_PERMISSION_BROKER_CLIENT_H_