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

//

// Copyright (c) 2006 Georgia Tech Research Corporation

// All rights reserved.

//

// 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: George F. Riley<riley@ece.gatech.edu>

//

#ifndef IPV4_H

#define IPV4_H

#include <list>

#include <stdint.h>

#include "ns3/callback-trace-source.h"

#include "ns3/array-trace-resolver.h"

#include "l3-protocol.h"

namespace ns3 {

class Packet;

class NetDevice;

class Ipv4Interface;

class Ipv4Address;

class Ipv4Header;

class Ipv4Route;

class Node;

class TraceResolver;

class TraceContext;

/**

 * ::Send is always defined in subclasses.

 */

class Ipv4 : public L3Protocol 

{

public:

  static const uint16_t PROT_NUMBER;

  enum TraceType {

    TX,

    RX,

    DROP,

    INTERFACES,

  };

  typedef ArrayTraceResolver<Ipv4Interface>::Index InterfaceIndex;

  Ipv4(Node *node);

  virtual ~Ipv4 ();

  /**

   * \param context the trace context to use to construct the

   *        TraceResolver to return

   * \returns a TraceResolver which can resolve all traces

   *          performed in this object. The caller must

   *          delete the returned object.

   */

  virtual TraceResolver *CreateTraceResolver (TraceContext const &context);

  /**

   * \param ttl default ttl to use

   *

   * When we need to send an ipv4 packet, we use this default

   * ttl value.

   */

  void SetDefaultTtl (uint8_t ttl);

  /**

   * \param dest destination address

   * \param nextHop address of next hop.

   * \param interface interface of next hop.

   *

   * add route to host dest through host nextHop 

   * on interface.

   */

  void AddHostRouteTo (Ipv4Address dest, 

                       Ipv4Address nextHop, 

                       uint32_t interface);

  /**

   * \param dest destination address

   * \param interface of next hop

   *

   * add route to host dest on interface.

   */

  void AddHostRouteTo (Ipv4Address dest, 

                       uint32_t interface);

  /**

   * \param network destination network

   * \param networkMask netmask of destination network

   * \param nextHop address of next hop

   * \param interface interface of next hop

   * 

   * add route to network dest with netmask 

   * through host nextHop on interface

   */

  void AddNetworkRouteTo (Ipv4Address network, 

                          Ipv4Mask networkMask, 

                          Ipv4Address nextHop, 

                          uint32_t interface);

  /**

   * \param network destination network

   * \param networkMask netmask of destination network

   * \param interface interface of next hop

   *

   * add route to network dest with netmask 

   * on interface

   */

  void AddNetworkRouteTo (Ipv4Address network, 

                          Ipv4Mask networkMask, 

                          uint32_t interface);

  /**

   * \param nextHop address of default next hop

   * \param interface interface of default next hop.

   * 

   * set the default route to host nextHop on

   * interface. 

   */

  void SetDefaultRoute (Ipv4Address nextHop, 

                        uint32_t interface);

  /**

   * \param dest destination address

   * \returns the route to the destination address

   *

   * Lookup the route for this destination address.

   */

  Ipv4Route *Lookup (Ipv4Address dest);

  /**

   * \returns the number of entries in the routing table.

   */

  uint32_t GetNRoutes (void);

  /**

   * \param i index of route to return

   * \returns the route whose index is i

   */

  Ipv4Route *GetRoute (uint32_t i);

  /**

   * \param i index of route to remove from routing table.

   */

  void RemoveRoute (uint32_t i);

  /**

   * \param interface interface to add to the list of ipv4 interfaces

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

   * \returns the index of the interface added.

   *

   * Once an interface has been added, it can never be removed: if you want

   * to disable it, you can invoke Ipv4Interface::SetDown which will

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

   */

  uint32_t AddInterface (NetDevice *device);

  /**

   * \param i index of interface to return

   * \returns the requested interface

   */

  Ipv4Interface * GetInterface (uint32_t i) const;

  /**

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

   */

  uint32_t GetNInterfaces (void) const;

  /**

   * \param device the device to match

   * \returns the matching interface, zero if not found.

   *

   * Try to find an Ipv4Interface whose NetDevice is equal to

   * the input NetDevice.

   */

  Ipv4Interface *FindInterfaceForDevice (NetDevice const*device);

  /**

   * Lower layer calls this method after calling L3Demux::Lookup

   * The ARP subclass needs to know from which NetDevice this

   * packet is coming to:

   *    - implement a per-NetDevice ARP cache

   *    - send back arp replies on the right device

   */

  virtual void Receive(Packet& p, NetDevice *device);

  /**

   * \param packet packet to send

   * \param source source address of packet

   * \param destination address of packet

   * \param protocol number of packet

   *

   * Higher-level layers call this method to send a packet

   * down the stack to the MAC and PHY layers.

   */

  void Send (Packet const &packet, Ipv4Address source, 

	     Ipv4Address destination, uint8_t protocol);

  void SetAddress (uint32_t i, Ipv4Address address);

  void SetNetworkMask (uint32_t i, Ipv4Mask mask);

  Ipv4Mask GetNetworkMask (uint32_t t) const;

  Ipv4Address GetAddress (uint32_t i) const;

  uint16_t GetMtu (uint32_t i) const;

  bool IsUp (uint32_t i) const;

  void SetUp (uint32_t i);

  void SetDown (uint32_t i);

protected:

  virtual void DoDispose (void);

private:

  void SendRealOut (Packet const &packet, Ipv4Header const &ip, Ipv4Route const &route);

  bool Forwarding (Packet const &packet, Ipv4Header &ipHeader, NetDevice *device);

  void ForwardUp (Packet p, Ipv4Header const&ip);

  uint32_t AddIpv4Interface (Ipv4Interface *interface);

  void SetupLoopback (void);

  TraceResolver *InterfacesCreateTraceResolver (TraceContext const &context) const;

  typedef std::list<Ipv4Interface*> Ipv4InterfaceList;

  typedef std::list<Ipv4Route *> HostRoutes;

  typedef std::list<Ipv4Route *>::const_iterator HostRoutesCI;

  typedef std::list<Ipv4Route *>::iterator HostRoutesI;

  typedef std::list<Ipv4Route *> NetworkRoutes;

  typedef std::list<Ipv4Route *>::const_iterator NetworkRoutesCI;

  typedef std::list<Ipv4Route *>::iterator NetworkRoutesI;

  Ipv4InterfaceList m_interfaces;

  uint32_t m_nInterfaces;

  uint8_t m_defaultTtl;

  uint16_t m_identification;

  HostRoutes m_hostRoutes;

  NetworkRoutes m_networkRoutes;

  Ipv4Route *m_defaultRoute;

  Node *m_node;

  CallbackTraceSource<Packet const &, uint32_t> m_txTrace;

  CallbackTraceSource<Packet const &, uint32_t> m_rxTrace;

  CallbackTraceSource<Packet const &> m_dropTrace;

};

} // Namespace ns3

#endif