/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2007 INRIA

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation;

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 */

#ifndef IPV4_H

#define IPV4_H

#include <stdint.h>

#include "ns3/object.h"

#include "ns3/socket.h"

#include "ns3/callback.h"

#include "ipv4-address.h"

#include "ipv4-interface-address.h"

namespace ns3 {

class Node;

class NetDevice;

class Packet;

class Ipv4RoutingProtocol;

/**

 * \ingroup node

 * \defgroup ipv4 Ipv4

 */

/**

 * \ingroup ipv4

 * \brief Access to the Ipv4 forwarding table, interfaces, and configuration

 *

 * This class defines the API to manipulate the following aspects of

 * the Ipv4 implementation:  

 * -# set/get an Ipv4RoutingProtocol 

 * -# register a NetDevice for use by the Ipv4 layer (basically, to

 * create Ipv4-related state such as addressing and neighbor cache that 

 * is associated with a NetDevice)

 * -# manipulate the status of the NetDevice from the Ipv4 perspective, 

 * such as marking it as Up or Down, 

 * -# adding, deleting, and getting addresses associated to the Ipv4 

 * interfaces.

 * -# exporting Ipv4 configuration attributes

 * 

 * Each NetDevice has conceptually a single Ipv4 interface associated

 * with it (the corresponding structure in the Linux Ipv4 implementation

 * is struct in_device).  Each interface may have one or more Ipv4

 * addresses associated with it.  Each Ipv4 address may have different

 * subnet mask, scope, etc., so all of this per-address information 

 * is stored in an Ipv4InterfaceAddress class (the corresponding 

 * structure in Linux is struct in_ifaddr)

 *

 * Ipv4 attributes such as whether IP forwarding is enabled and disabled

 * are also stored in this class

 *

 * TO DO:  Add API to allow access to the Ipv4 neighbor table

 *

 * \see Ipv4RoutingProtocol

 * \see Ipv4InterfaceAddress

 */

class Ipv4 : public Object

{

public:

  static TypeId GetTypeId (void);

  Ipv4 ();

  virtual ~Ipv4 ();

  /**

   * \brief Register a new routing protocol to be used by this Ipv4 stack

   *   

   * This call will replace any routing protocol that has been previously 

   * registered.  If you want to add multiple routing protocols, you must

   * add them to a Ipv4ListRoutingProtocol directly.

   * 

   * \param routingProtocol smart pointer to Ipv4RoutingProtocol object

   */

  virtual void SetRoutingProtocol (Ptr<Ipv4RoutingProtocol> routingProtocol) = 0;

  /**

   * \brief Get the routing protocol to be used by this Ipv4 stack

   * 

   * \returns smart pointer to Ipv4RoutingProtocol object, or null pointer if none

   */

  virtual Ptr<Ipv4RoutingProtocol> GetRoutingProtocol (void) const = 0;

  /**

   * \param device device to add to the list of Ipv4 interfaces

   *        which can be used as output interfaces during packet forwarding.

   * \returns the index of the Ipv4 interface added.

   *

   * Once a device has been added, it can never be removed: if you want

   * to disable it, you can invoke Ipv4::SetDown which will

   * make sure that it is never used during packet forwarding.

   */

  virtual uint32_t AddInterface (Ptr<NetDevice> device) = 0;

  /**

   * \returns the number of interfaces added by the user.

   */

  virtual uint32_t GetNInterfaces (void) const = 0;  

  /**

   * \brief Return the interface number of the interface that has been

   *        assigned the specified IP address.

   *

   * \param address The IP address being searched for

   * \returns The interface number of the Ipv4 interface with the given 

   *          address or -1 if not found.

   *

   * Each IP interface has one or more IP addresses associated with it.  

   * This method searches the list of interfaces for one that holds a

   * particular address.  This call takes an IP address as a parameter and

   * returns the interface number of the first interface that has been assigned

   * that address, or -1 if not found.  There must be an exact match.

   */

  virtual int32_t GetInterfaceForAddress (Ipv4Address address) const = 0;

  /**

   * \brief Return the interface number of first interface found that 

   *  has an Ipv4 address within the prefix specified by the input

   *  address and mask parameters

   *

   * \param address The IP address assigned to the interface of interest.

   * \param mask The IP prefix to use in the mask

   * \returns The interface number of the Ipv4 interface with the given 

   *          address or -1 if not found.

   *

   * Each IP interface has one or more IP addresses associated with it.  

   * This method searches the list of interfaces for the first one found

   * that holds an address that is included within the prefix 

   * formed by the input address and mask parameters.  The value -1 is

   * returned if no match is found.

   */

  virtual int32_t GetInterfaceForPrefix (Ipv4Address address,

    Ipv4Mask mask) const = 0;

  /**

   * \param interface The interface number of an Ipv4 interface.

   * \returns The NetDevice associated with the Ipv4 interface number.

   */

  virtual Ptr<NetDevice> GetNetDevice (uint32_t interface) = 0;

  /**

   * \param device The NetDevice for an Ipv4Interface

   * \returns The interface number of an Ipv4 interface or -1 if not found.

   */

  virtual int32_t GetInterfaceForDevice (Ptr<const NetDevice> device) const = 0;

  /**

   * \param interface Interface number of an Ipv4 interface

   * \param address Ipv4InterfaceAddress address to associate with the underlying Ipv4 interface

   * \returns true if the operation succeeded

   */

  virtual bool AddAddress (uint32_t interface, Ipv4InterfaceAddress address) = 0;

  /**

   * \param interface Interface number of an Ipv4 interface

   * \returns the number of Ipv4InterfaceAddress entries for the interface.

   */

  virtual uint32_t GetNAddresses (uint32_t interface) const = 0;

  /**

   * Because addresses can be removed, the addressIndex is not guaranteed

   * to be static across calls to this method.

   * 

   * \param interface Interface number of an Ipv4 interface

   * \param addressIndex index of Ipv4InterfaceAddress 

   * \returns the Ipv4InterfaceAddress associated to the interface and addresIndex

   */

  virtual Ipv4InterfaceAddress GetAddress (uint32_t interface, uint32_t addressIndex) const = 0;

  /**

   * Remove the address at addressIndex on named interface.  The addressIndex

   * for all higher indices will decrement by one after this method is called;

   * so, for example, to remove 5 addresses from an interface i, one could

   * call RemoveAddress (i, 0); 5 times.  

   * 

   * \param interface Interface number of an Ipv4 interface

   * \param addressIndex index of Ipv4InterfaceAddress to remove 

   * \returns true if the operation succeeded

   */

  virtual bool RemoveAddress (uint32_t interface, uint32_t addressIndex) = 0;

  /**

   * \param interface The interface number of an Ipv4 interface

   * \param metric routing metric (cost) associated to the underlying 

   *          Ipv4 interface

   */

  virtual void SetMetric (uint32_t interface, uint16_t metric) = 0;

  /**

   * \param interface The interface number of an Ipv4 interface

   * \returns routing metric (cost) associated to the underlying 

   *          Ipv4 interface

   */

  virtual uint16_t GetMetric (uint32_t interface) const = 0;

  /**

   * \param interface Interface number of Ipv4 interface

   * \returns the Maximum Transmission Unit (in bytes) associated

   *          to the underlying Ipv4 interface

   */

  virtual uint16_t GetMtu (uint32_t interface) const = 0;

  /**

   * \param interface Interface number of Ipv4 interface

   * \returns true if the underlying interface is in the "up" state,

   *          false otherwise.

   */

  virtual bool IsUp (uint32_t interface) const = 0;

  /**

   * \param interface Interface number of Ipv4 interface

   * 

   * Set the interface into the "up" state. In this state, it is

   * considered valid during Ipv4 forwarding.

   */

  virtual void SetUp (uint32_t interface) = 0;

  /**

   * \param interface Interface number of Ipv4 interface

   *

   * Set the interface into the "down" state. In this state, it is

   * ignored during Ipv4 forwarding.

   */

  virtual void SetDown (uint32_t interface) = 0;

  /**

   * \param interface Interface number of Ipv4 interface

   * \returns true if IP forwarding enabled for input datagrams on this device

   */

  virtual bool IsForwarding (uint32_t interface) const = 0;

  /**

   * \param interface Interface number of Ipv4 interface

   * \param val Value to set the forwarding flag

   * 

   * If set to true, IP forwarding is enabled for input datagrams on this device

   */

  virtual void SetForwarding (uint32_t interface, bool val) = 0;

  static const uint32_t IF_ANY = 0xffffffff;

private:

  // Indirect the Ipv4 attributes through private pure virtual methods

  virtual void SetIpForward (bool forward) = 0;

  virtual bool GetIpForward (void) const = 0;

};

} // namespace ns3 

#endif /* IPV4_H */