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

/*

 * Copyright (c) 2005,2006,2007 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>

 */

#include "ipv4-interface.h"

#include "loopback-net-device.h"

#include "ns3/ipv4-address.h"

#include "ipv4-l3-protocol.h"

#include "arp-l3-protocol.h"

#include "arp-cache.h"

#include "ns3/net-device.h"

#include "ns3/log.h"

#include "ns3/packet.h"

#include "ns3/node.h"

#include "ns3/pointer.h"

NS_OBJECT_ENSURE_REGISTERED (Ipv4Interface);

TypeId 

Ipv4Interface::GetTypeId (void)

{

  static TypeId tid = TypeId ("ns3::Ipv4Interface")

    .SetParent<Object> ()

    .AddAttribute ("ArpCache",

                   "The arp cache for this ipv4 interface",

                   PointerValue (0),

                   MakePointerAccessor (&Ipv4Interface::SetArpCache, 

                                        &Ipv4Interface::GetArpCache),

                   MakePointerChecker<ArpCache> ())

  ;

  ;

  return tid;

}

/** 

 * By default, Ipv4 interface are created in the "down" state

 *  with no IP addresses.  Before becoming useable, the user must 

 * invoke SetUp on them once an Ipv4 address and mask have been set.

 */

Ipv4Interface::Ipv4Interface () 

  : m_ifup (false),

    m_forwarding (true),

    m_metric (1),

    m_node (0), 

    m_device (0),

    m_cache (0)

{

  NS_LOG_FUNCTION (this);

}

Ipv4Interface::~Ipv4Interface ()

{

  NS_LOG_FUNCTION (this);

}

void

Ipv4Interface::DoDispose (void)

{

  NS_LOG_FUNCTION (this);

  m_node = 0;

  m_device = 0;

  Object::DoDispose ();

}

void 

Ipv4Interface::SetNode (Ptr<Node> node)

{

  NS_LOG_FUNCTION (this << node);

  m_node = node;

  DoSetup ();

}

void 

Ipv4Interface::SetDevice (Ptr<NetDevice> device)

{

  NS_LOG_FUNCTION (this << device);

  m_device = device;

  DoSetup ();

}

void

Ipv4Interface::DoSetup (void)

{

  NS_LOG_FUNCTION (this);

  if (m_node == 0 || m_device == 0)

    {

      return;

    }

  if (!m_device->NeedsArp ())

    {

      return;

    }

  Ptr<ArpL3Protocol> arp = m_node->GetObject<ArpL3Protocol> ();

  m_cache = arp->CreateCache (m_device, this);

}

Ptr<NetDevice>

Ipv4Interface::GetDevice (void) const

{

  NS_LOG_FUNCTION (this);

  return m_device;

}

void

Ipv4Interface::SetMetric (uint16_t metric)

{

  NS_LOG_FUNCTION (this << metric);

  m_metric = metric;

}

uint16_t

Ipv4Interface::GetMetric (void) const

{

  NS_LOG_FUNCTION (this);

  return m_metric;

}

void

Ipv4Interface::SetArpCache (Ptr<ArpCache> a)

{

  NS_LOG_FUNCTION (this << a);

  m_cache = a;

}

Ptr<ArpCache>

Ipv4Interface::GetArpCache () const

{

  NS_LOG_FUNCTION (this);

  return m_cache;

}

/**

 * These are IP interface states and may be distinct from 

 * NetDevice states, such as found in real implementations

 * (where the device may be down but IP interface state is still up).

 */

bool 

Ipv4Interface::IsUp (void) const

{

  NS_LOG_FUNCTION (this);

  return m_ifup;

}

bool 

Ipv4Interface::IsDown (void) const

{

  NS_LOG_FUNCTION (this);

  return !m_ifup;

}

void 

Ipv4Interface::SetUp (void)

{

  NS_LOG_FUNCTION (this);

  m_ifup = true;

}

void 

Ipv4Interface::SetDown (void)

{

  NS_LOG_FUNCTION (this);

  m_ifup = false;

}

bool 

Ipv4Interface::IsForwarding (void) const

{

  NS_LOG_FUNCTION (this);

  return m_forwarding;

}

void 

Ipv4Interface::SetForwarding (bool val)

{

  NS_LOG_FUNCTION (this << val);

  m_forwarding = val;

}

void

Ipv4Interface::Send (Ptr<Packet> p, Ipv4Address dest)

{

  NS_LOG_FUNCTION (this << *p << dest);

  if (!IsUp ())

    {

      return;

    }

  // Check for a loopback device

  if (DynamicCast<LoopbackNetDevice> (m_device))

    {

      /// \todo additional checks needed here (such as whether multicast

      /// goes to loopback)?

      m_device->Send (p, m_device->GetBroadcast (), 

                      Ipv4L3Protocol::PROT_NUMBER);

      return;

    } 

  // is this packet aimed at a local interface ?

  for (Ipv4InterfaceAddressListCI i = m_ifaddrs.begin (); i != m_ifaddrs.end (); ++i)

    {

      if (dest == (*i).GetLocal ())

        {

          Ptr<Ipv4L3Protocol> ipv4 = m_node->GetObject<Ipv4L3Protocol> ();

          ipv4->Receive (m_device, p, Ipv4L3Protocol::PROT_NUMBER, 

                         m_device->GetBroadcast (),

                         m_device->GetBroadcast (),

                         NetDevice::PACKET_HOST // note: linux uses PACKET_LOOPBACK here

                         );

          return;

        }

    }

  if (m_device->NeedsArp ())

    {

      NS_LOG_LOGIC ("Needs ARP" << " " << dest);

      Ptr<ArpL3Protocol> arp = m_node->GetObject<ArpL3Protocol> ();

      Address hardwareDestination;

      bool found = false;

      if (dest.IsBroadcast ())

        {

          NS_LOG_LOGIC ("All-network Broadcast");

          hardwareDestination = m_device->GetBroadcast ();

          found = true;

        }

      else if (dest.IsMulticast ())

        {

          NS_LOG_LOGIC ("IsMulticast");

          NS_ASSERT_MSG (m_device->IsMulticast (),

                         "ArpIpv4Interface::SendTo (): Sending multicast packet over "

                         "non-multicast device");

          hardwareDestination = m_device->GetMulticast (dest);

          found = true;

        }

      else

        {

          for (Ipv4InterfaceAddressListCI i = m_ifaddrs.begin (); i != m_ifaddrs.end (); ++i)

            {

              if (dest.IsSubnetDirectedBroadcast ((*i).GetMask ()))

                {

                  NS_LOG_LOGIC ("Subnetwork Broadcast");

                  hardwareDestination = m_device->GetBroadcast ();

                  found = true;

                  break;

                }

            }

          if (!found)

            {

              NS_LOG_LOGIC ("ARP Lookup");

              found = arp->Lookup (p, dest, m_device, m_cache, &hardwareDestination);

            }

        }

      if (found)

        {

          NS_LOG_LOGIC ("Address Resolved.  Send.");

          m_device->Send (p, hardwareDestination,

                          Ipv4L3Protocol::PROT_NUMBER);

        }

    }

  else

    {

      NS_LOG_LOGIC ("Doesn't need ARP");

      m_device->Send (p, m_device->GetBroadcast (), 

                      Ipv4L3Protocol::PROT_NUMBER);

    }

}

uint32_t

Ipv4Interface::GetNAddresses (void) const

{

  NS_LOG_FUNCTION (this);

  return m_ifaddrs.size ();

}

bool

Ipv4Interface::AddAddress (Ipv4InterfaceAddress addr)

{

  NS_LOG_FUNCTION (this << addr);

  m_ifaddrs.push_back (addr);

  return true;

}

Ipv4InterfaceAddress

Ipv4Interface::GetAddress (uint32_t index) const

{

  NS_LOG_FUNCTION (this << index);

  if (index < m_ifaddrs.size ())

    {

      uint32_t tmp = 0;

      for (Ipv4InterfaceAddressListCI i = m_ifaddrs.begin (); i!= m_ifaddrs.end (); i++)

        {

          if (tmp  == index)

            {

              return *i;

            }

          ++tmp;

        }

    }

  NS_ASSERT (false);  // Assert if not found

  Ipv4InterfaceAddress addr;

  return (addr);  // quiet compiler

}

Ipv4InterfaceAddress

Ipv4Interface::RemoveAddress (uint32_t index)

{

  NS_LOG_FUNCTION (this << index);

  if (index >= m_ifaddrs.size ())

    {

      NS_ASSERT_MSG (false, "Bug in Ipv4Interface::RemoveAddress");

    }

  Ipv4InterfaceAddressListI i = m_ifaddrs.begin ();

  uint32_t tmp = 0;

  while (i != m_ifaddrs.end ())

    {

      if (tmp  == index)

        {

          Ipv4InterfaceAddress addr = *i;

          m_ifaddrs.erase (i);

          return addr;

        }

      ++tmp;

      ++i;

    }

  NS_ASSERT_MSG (false, "Address " << index << " not found");

  Ipv4InterfaceAddress addr;

  return (addr);  // quiet compiler

}

Ipv4InterfaceAddress

Ipv4Interface::RemoveAddress(Ipv4Address address)

{

  NS_LOG_FUNCTION(this << address);

  if (address == address.GetLoopback())

    {

      NS_LOG_WARN ("Cannot remove loopback address.");

      return Ipv4InterfaceAddress();

    }

  for(Ipv4InterfaceAddressListI it = m_ifaddrs.begin(); it != m_ifaddrs.end(); it++)

    {

      if((*it).GetLocal() == address)

        {

          Ipv4InterfaceAddress ifAddr = *it;

          m_ifaddrs.erase(it);

          return ifAddr;

        }

    }

  return Ipv4InterfaceAddress();

}

} // namespace ns3