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

/*

 * Copyright (c) 2010 Hajime Tazaki

 *

 * 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

 *

 * Authors: Hajime Tazaki <tazaki@sfc.wide.ad.jp>

 */

#ifndef IPV6_PACKET_INFO_TAG_H

#define IPV6_PACKET_INFO_TAG_H

#include "ns3/tag.h"

#include "ns3/ipv6-address.h"

namespace ns3 {

class Node;

class Packet;

/**

 * \brief This class implements a tag that carries socket ancillary 

 * data to the socket interface. This is used like 

 * socket option of IP_PKTINFO/IPV6_PKTINFO in \RFC{3542}

 *

 * This tag in the send direction is presently not enabled but we

 * would accept a patch along those lines in the future. To include

 * the nexthop in the send direction would increase the size of the

 * tag beyond 20 bytes, so in that case, we recommend that an

 * additional tag be used to carry the IPv6 next hop address.

 */

class Ipv6PacketInfoTag : public Tag

{

public:

  Ipv6PacketInfoTag ();

  /**

   * \brief Get the type ID.

   * \return the object TypeId

   */

  static TypeId GetTypeId (void);

  /**

   * \brief Set the tag's address

   *

   * \param addr the address

   */

  void SetAddress (Ipv6Address addr);

  /**

   * \brief Get the tag's address

   *

   * \returns the address

   */

  Ipv6Address GetAddress (void) const;

  /**

   * \brief Set the tag's receiving interface

   *

   * \param ifindex the interface index

   */

  void SetRecvIf (uint32_t ifindex);

  /**

   * \brief Get the tag's receiving interface

   *

   * \returns the interface index

   */

  uint32_t GetRecvIf (void) const;

  /**

   * \brief Set the tag's Hop Limit

   *

   * \param ttl the hop limit

   */

  void SetHoplimit (uint8_t ttl);

  /**

   * \brief Get the tag's Hop Limit

   *

   * \returns the Hop Limit

   */

  uint8_t GetHoplimit (void) const;

  /**

   * \brief Set the tag's Traffic Class

   *

   * \param tclass the Traffic Class

   */

  void SetTrafficClass (uint8_t tclass);

  /**

   * \brief Get the tag's Traffic Class

   *

   * \returns the Traffic Class

   */

  uint8_t GetTrafficClass (void) const;

  // inherited functions, no doc necessary

  virtual TypeId GetInstanceTypeId (void) const;

  virtual uint32_t GetSerializedSize (void) const;

  virtual void Serialize (TagBuffer i) const;

  virtual void Deserialize (TagBuffer i);

  virtual void Print (std::ostream &os) const;

private:

  /* 

   * RFC 3542 includes

   * for outgoing packet,

   *  1.  the source IPv6 address,

   *  2.  the outgoing interface index,

   *  3.  the outgoing hop limit,

   *  4.  the next hop address, and

   *  5.  the outgoing traffic class value.

   *

   * for incoming packet,

   *  1.  the destination IPv6 address,

   *  2.  the arriving interface index,

   *  3.  the arriving hop limit, and

   *  4.  the arriving traffic class value.

  */

  Ipv6Address m_addr;  //!< the packet address (src or dst)

  uint8_t m_ifindex;   //!< the Interface index

  uint8_t m_hoplimit;  //!< the Hop Limit

  uint8_t m_tclass;    //!< the Traffic Class

};

} // namespace ns3

#endif /* IPV6_PACKET_INFO_TAG_H */