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

/*

 * Copyright (c) 2007-2009 Strasbourg University

 *

 * 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: David Gross <gdavid.devel@gmail.com>

 */

#ifndef IPV6_EXTENSION_H

#define IPV6_EXTENSION_H

#include <map>

#include <list>

#include "ns3/object.h"

#include "ns3/node.h"

#include "ns3/ptr.h"

#include "ipv6-interface.h"

#include "ns3/ipv6-header.h"

#include "ns3/buffer.h"

#include "ns3/packet.h"

#include "ns3/random-variable-stream.h"

#include "ns3/ipv6-address.h"

#include "ns3/ipv6-l3-protocol.h"

#include "ns3/traced-callback.h"

namespace ns3 {

/**

 * \class Ipv6Extension

 * \brief IPv6 Extension base

 * If you want to implement a new IPv6 extension, all you have to do is

 * implement a subclass of this class and add it to an Ipv6ExtensionDemux.

 */

class Ipv6Extension : public Object

{

public:

  /**

   * \brief Get the type identificator.

   * \return type identificator

   */

  static TypeId GetTypeId ();

  /**

   * \brief Constructor.

   */

  Ipv6Extension ();

  /**

   * \brief Destructor.

   */

  virtual ~Ipv6Extension ();

  /**

   * \brief Set the node.

   * \param node the node to set

   */

  void SetNode (Ptr<Node> node);

  /**

   * \brief Get the node.

   * \return the node

   */

  Ptr<Node> GetNode () const;

  /**

   * \brief Get the extension number.

   * \return extension number

   */

  virtual uint8_t GetExtensionNumber () const = 0;

  /**

   * \brief Process method

   * Called from Ipv6L3Protocol::Receive.

   *

   * \param packet the packet

   * \param offset the offset of the extension to process

   * \param ipv6Header the IPv6 header of packet received

   * \param dst destination address of the packet received (i.e. us)

   * \param nextHeader the next header

   * \param stopProcessing true if the packet must not be further processed

   * \param isDropped true if the packet must be dropped

   * \param dropReason dropping reason

   * \return the size processed

   */

  virtual uint8_t Process (Ptr<Packet>& packet,

                           uint8_t offset,

                           Ipv6Header const& ipv6Header,

                           Ipv6Address dst,

                           uint8_t *nextHeader,

                           bool& stopProcessing,

                           bool& isDropped,

                           Ipv6L3Protocol::DropReason& dropReason) = 0;

  /**

   * \brief Process options

   * Called by implementing classes to process the options

   *

   * \param packet the packet

   * \param offset the offset of the first option to process

   * \param length the total length of all options (as specified in the extension header)

   * \param ipv6Header the IPv6 header of packet received

   * \param dst destination address of the packet received (i.e. us)

   * \param nextHeader the next header

   * \param stopProcessing true if the packet must not be further processed

   * \param isDropped true if the packet must be dropped

   * \param dropReason dropping reason

   * \return the size processed

   */

  virtual uint8_t ProcessOptions (Ptr<Packet>& packet,

                                  uint8_t offset,

                                  uint8_t length,

                                  Ipv6Header const& ipv6Header,

                                  Ipv6Address dst,

                                  uint8_t *nextHeader,

                                  bool& stopProcessing,

                                  bool& isDropped,

                                  Ipv6L3Protocol::DropReason& dropReason

                                  );

 /**

  * Assign a fixed random variable stream number to the random variables

  * used by this model.  Return the number of streams (possibly zero) that

  * have been assigned.

  *

  * \param stream first stream index to use

  * \return the number of stream indices assigned by this model

  */

  int64_t AssignStreams (int64_t stream);

protected:

  /**

   * \brief Provides uniform random variables.

   */

  Ptr<UniformRandomVariable> m_uvar;

private:

  /**

   * \brief The node.

   */

  Ptr<Node> m_node;

};

/**

 * \class Ipv6ExtensionHopByHop

 * \brief IPv6 Extension "Hop By Hop"

 */

class Ipv6ExtensionHopByHop : public Ipv6Extension

{

public:

  /**

   * \brief Hop-by-hop extension number.

   */

  static const uint8_t EXT_NUMBER = 0;

  /**

   * \brief Get the type identificator.

   * \return type identificator

   */

  static TypeId GetTypeId ();

  /**

   * \brief Constructor.

   */

  Ipv6ExtensionHopByHop ();

  /**

   * \brief Destructor.

   */

  ~Ipv6ExtensionHopByHop ();

  /**

   * \brief Get the extension number.

   * \return extension number

   */

  virtual uint8_t GetExtensionNumber () const;

  virtual uint8_t Process (Ptr<Packet>& packet,

                           uint8_t offset,

                           Ipv6Header const& ipv6Header,

                           Ipv6Address dst,

                           uint8_t *nextHeader,

                           bool& stopProcessing,

                           bool& isDropped,

                           Ipv6L3Protocol::DropReason& dropReason);

};

/**

 * \class Ipv6ExtensionDestination

 * \brief IPv6 Extension Destination

 */

class Ipv6ExtensionDestination : public Ipv6Extension

{

public:

  /**

   * \brief Destination extension number.

   */

  static const uint8_t EXT_NUMBER = 60;

  /**

   * \brief Get the type identificator.

   * \return type identificator

   */

  static TypeId GetTypeId ();

  /**

   * \brief Constructor.

   */

  Ipv6ExtensionDestination ();

  /**

   * \brief Destructor.

   */

  ~Ipv6ExtensionDestination ();

  /**

   * \brief Get the extension number.

   * \return extension number

   */

  virtual uint8_t GetExtensionNumber () const;

  virtual uint8_t Process (Ptr<Packet>& packet,

                           uint8_t offset,

                           Ipv6Header const& ipv6Header,

                           Ipv6Address dst,

                           uint8_t *nextHeader,

                           bool& stopProcessing,

                           bool& isDropped,

                           Ipv6L3Protocol::DropReason& dropReason);

};

/**

 * \class Ipv6ExtensionFragment

 * \brief IPv6 Extension Fragment

 */

class Ipv6ExtensionFragment : public Ipv6Extension

{

public:

  /**

   * \brief Fragmentation extension number.

   */

  static const uint8_t EXT_NUMBER = 44;

  /**

    * \brief Get the type identificator.

    * \return type identificator

    */

  static TypeId GetTypeId ();

  /**

   * \brief Constructor.

   */

  Ipv6ExtensionFragment ();

  /**

   * \brief Destructor.

   */

  ~Ipv6ExtensionFragment ();

  /**

   * \brief Get the extension number.

   * \return extension number

   */

  virtual uint8_t GetExtensionNumber () const;

  virtual uint8_t Process (Ptr<Packet>& packet,

                           uint8_t offset,

                           Ipv6Header const& ipv6Header,

                           Ipv6Address dst,

                           uint8_t *nextHeader,

                           bool& stopProcessing,

                           bool& isDropped,

                           Ipv6L3Protocol::DropReason& dropReason);

  /**

   * \brief Fragment a packet

   * \param packet the packet

   * \param fragmentSize the maximal size of the fragment (unfragmentable part + fragmentation header + fragmentable part)

   * \param listFragments the list of fragments

   */

  void GetFragments (Ptr<Packet> packet, uint32_t fragmentSize, std::list<Ptr<Packet> >& listFragments);

protected:

  /**

   * \brief Dispose this object.

   */

  virtual void DoDispose ();

private:

  /**

   * \class Fragments

   * \brief A Set of Fragment

   */

  class Fragments : public SimpleRefCount<Fragments>

  {

public:

    /**

     * \brief Constructor.

     */

    Fragments ();

    /**

     * \brief Destructor.

     */

    ~Fragments ();

    /**

     * \brief Add a fragment.

     * \param fragment the fragment

     * \param fragmentOffset the offset of the fragment

     * \param moreFragment the bit "More Fragment"

     */

    void AddFragment (Ptr<Packet> fragment, uint16_t fragmentOffset, bool moreFragment);

    /**

     * \brief Set the unfragmentable part of the packet.

     * \param unfragmentablePart the unfragmentable part

     */

    void SetUnfragmentablePart (Ptr<Packet> unfragmentablePart);

    /**

     * \brief If all fragments have been added.

     * \returns true if the packet is entire

     */

    bool IsEntire () const;

    /**

     * \brief Get the entire packet.

     * \return the entire packet

     */

    Ptr<Packet> GetPacket () const;

    /**

     * \brief Get the packet parts so far received.

     * \return the partial packet

     */

    Ptr<Packet> GetPartialPacket () const;

    /**

     * \brief Set the Timeout EventId.

     */

    void SetTimeoutEventId (EventId event);

    /**

     * \brief Cancel the timeout event

     */

    void CancelTimeout ();

private:

    /**

     * \brief If other fragments will be sent.

     */

    bool m_moreFragment;

    /**

     * \brief The current fragments.

     */

    std::list<std::pair<Ptr<Packet>, uint16_t> > m_packetFragments;

    /**

     * \brief The unfragmentable part.

     */

    Ptr<Packet> m_unfragmentable;

    /**

     * \brief Timeout handler event

     */

    EventId m_timeoutEventId;

  };

  /**

   * \brief Process the timeout for packet fragments

   * \param key representing the packet fragments

   * \param ipHeader the IP header of the original packet

   */

  void HandleFragmentsTimeout (std::pair<Ipv6Address, uint32_t> key, Ipv6Header ipHeader);

  /**

   * \brief Get the packet parts so far received.

   * \return the partial packet

   */

  Ptr<Packet> GetPartialPacket () const;

  /**

   * \brief Set the Timeout EventId.

   */

  void SetTimeoutEventId (EventId event);

  /**

   * \brief Cancel the timeout event

   */

  void CancelTimeout ();

  /**

   * \brief Container for the packet fragments.

   */

  typedef std::map<std::pair<Ipv6Address, uint32_t>, Ptr<Fragments> > MapFragments_t;

  /**

   * \brief The hash of fragmented packets.

   */

  MapFragments_t m_fragments;

};

/**

 * \class Ipv6ExtensionRouting

 * \brief IPv6 Extension Routing

 * If you want to implement a new IPv6 routing extension, all you have to do is

 * implement a subclass of this class and add it to an Ipv6ExtensionRoutingDemux.

 */

class Ipv6ExtensionRouting : public Ipv6Extension

{

public:

  /**

   * \brief Routing extension number.

   */

  static const uint8_t EXT_NUMBER = 43;

  /**

   * \brief Get the type identificator.

   * \return type identificator

   */

  static TypeId GetTypeId ();

  /**

   * \brief Constructor.

   */

  Ipv6ExtensionRouting ();

  /**

   * \brief Destructor.

   */

  ~Ipv6ExtensionRouting ();

  /**

   * \brief Get the extension number.

   * \return extension number

   */

  virtual uint8_t GetExtensionNumber () const;

  /**

   * \brief Get the type of routing.

   * \return type of routing

   */

  virtual uint8_t GetTypeRouting () const;

  virtual uint8_t Process (Ptr<Packet>& packet,

                           uint8_t offset,

                           Ipv6Header const& ipv6Header,

                           Ipv6Address dst,

                           uint8_t *nextHeader,

                           bool& stopProcessing,

                           bool& isDropped,

                           Ipv6L3Protocol::DropReason& dropReason);

};

/**

 * \class Ipv6ExtensionRoutingDemux

 * \brief IPv6 Extension Routing Demux.

 */

class Ipv6ExtensionRoutingDemux : public Object

{

public:

  /**

   * \brief The interface ID.

   * \return type ID

   */

  static TypeId GetTypeId ();

  /**

   * \brief Constructor.

   */

  Ipv6ExtensionRoutingDemux ();

  /**

   * \brief Destructor.

   */

  virtual ~Ipv6ExtensionRoutingDemux ();

  /**

   * \brief Set the node.

   * \param node the node to set