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

/*

 * 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: Gustavo Carneiro  <gjc@inescporto.pt>

 */

#ifndef BRIDGE_NET_DEVICE_H

#define BRIDGE_NET_DEVICE_H

#include "ns3/net-device.h"

#include "ns3/mac48-address.h"

#include "ns3/nstime.h"

#include "ns3/bridge-channel.h"

#include <stdint.h>

#include <string>

#include <map>

namespace ns3 {

class Node;

/**

 * \ingroup devices

 * \defgroup bridge Bridge

 * 

 * \brief a virtual net device that bridges multiple LAN segments

 *

 * The BridgeNetDevice object is a "virtual" netdevice that aggregates

 * multiple "real" netdevices and implements the data plane forwarding

 * part of IEEE 802.1D.  By adding a BridgeNetDevice to a Node, it

 * will act as a "bridge", or "switch", to multiple LAN segments.

 * 

 * By default the bridge netdevice implements a "learning bridge"

 * algorithm (see 802.1D), where incoming unicast frames from one port

 * may occasionally be forwarded throughout all other ports, but

 * usually they are forwarded only to a single correct output port.

 *

 * \attention The Spanning Tree Protocol part of 802.1D is not

 * implemented.  Therefore, you have to be careful not to create

 * bridging loops, or else the network will collapse.

 *

 * \attention Bridging is designed to work only with NetDevices

 * modelling IEEE 802-style technologies, such as CsmaNetDevice and

 * WifiNetDevice.

 *

 * \attention If including a WifiNetDevice in a bridge, the wifi

 * device must be in Access Point mode.  Adhoc mode is not supported

 * with bridging.

 */

/**

 * \ingroup bridge

 * \brief a virtual net device that bridges multiple LAN segments

 */

class BridgeNetDevice : public NetDevice

{

public:

  static TypeId GetTypeId (void);

  BridgeNetDevice ();

  /** \brief Add a 'port' to a bridge device

   *

   * This method adds a new bridge port to a BridgeNetDevice, so that

   * the new bridge port NetDevice becomes part of the bridge and L2

   * frames start being forwarded to/from this NetDevice.

   *

   * \attention The netdevice that is being added as bridge port must

   * _not_ have an IP address.  In order to add IP connectivity to a

   * bridging node you must enable IP on the BridgeNetDevice itself,

   * never on its port netdevices.

   */

  void AddBridgePort (Ptr<NetDevice> bridgePort);

  // inherited from NetDevice base class.

  virtual void SetName(const std::string name);

  virtual std::string GetName(void) const;

  virtual void SetIfIndex(const uint32_t index);

  virtual uint32_t GetIfIndex(void) const;

  virtual Ptr<Channel> GetChannel (void) const;

  virtual Address GetAddress (void) const;

  virtual bool SetMtu (const uint16_t mtu);

  virtual uint16_t GetMtu (void) const;

  virtual bool IsLinkUp (void) const;

  virtual void SetLinkChangeCallback (Callback<void> callback);

  virtual bool IsBroadcast (void) const;

  virtual Address GetBroadcast (void) const;

  virtual bool IsMulticast (void) const;

  virtual Address GetMulticast (Ipv4Address multicastGroup) const;

  virtual bool IsPointToPoint (void) const;

  virtual bool Send (Ptr<Packet> packet, const Address& dest, uint16_t protocolNumber);

  virtual bool SendFrom (Ptr<Packet> packet, const Address& source, const Address& dest, uint16_t protocolNumber);

  virtual Ptr<Node> GetNode (void) const;

  virtual void SetNode (Ptr<Node> node);

  virtual bool NeedsArp (void) const;

  virtual void SetReceiveCallback (NetDevice::ReceiveCallback cb);

  virtual void SetPromiscReceiveCallback (NetDevice::PromiscReceiveCallback cb);

  virtual bool SupportsSendFrom () const;

  virtual Address GetMulticast (Ipv6Address addr) const;

protected:

  virtual void DoDispose (void);

  void ReceiveFromDevice (Ptr<NetDevice> device, Ptr<const Packet> packet, uint16_t protocol,

                          Address const &source, Address const &destination, PacketType packetType);

  void ForwardUnicast (Ptr<NetDevice> incomingPort, Ptr<const Packet> packet,

                       uint16_t protocol, Mac48Address src, Mac48Address dst);

  void ForwardBroadcast (Ptr<NetDevice> incomingPort, Ptr<const Packet> packet,

                         uint16_t protocol, Mac48Address src, Mac48Address dst);

  void Learn (Mac48Address source, Ptr<NetDevice> port);

  Ptr<NetDevice> GetLearnedState (Mac48Address source);

private:

  NetDevice::ReceiveCallback m_rxCallback;

  NetDevice::PromiscReceiveCallback m_promiscRxCallback;

  Mac48Address m_address;

  Time m_expirationTime; // time it takes for learned MAC state to expire

  struct LearnedState

  {

    Ptr<NetDevice> associatedPort;

    Time expirationTime;

  };

  std::map<Mac48Address, LearnedState> m_learnState;

  Ptr<Node> m_node;

  Ptr<BridgeChannel> m_channel;

  std::string m_name;

  std::vector< Ptr<NetDevice> > m_ports;

  uint32_t m_ifIndex;

  uint16_t m_mtu;

  bool m_enableLearning;

};

} // namespace ns3

#endif /* BRIDGE_NET_DEVICE_H */