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

//

// Copyright (c) 2006 Georgia Tech Research Corporation

//

// 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>

//

#include "ns3/packet.h"

#include "ns3/log.h"

#include "ns3/callback.h"

#include "ns3/ipv4-address.h"

#include "ns3/ipv4-route.h"

#include "ns3/node.h"

#include "ns3/socket.h"

#include "ns3/net-device.h"

#include "ns3/uinteger.h"

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

#include "ns3/object-vector.h"

#include "ns3/ipv4-header.h"

#include "ns3/boolean.h"

#include "ns3/ipv4-routing-table-entry.h"

#include "loopback-net-device.h"

#include "arp-l3-protocol.h"

#include "ipv4-l3-protocol.h"

#include "ipv4-l4-protocol.h"

#include "icmpv4-l4-protocol.h"

#include "ipv4-interface.h"

#include "ipv4-raw-socket-impl.h"

NS_LOG_COMPONENT_DEFINE ("Ipv4L3Protocol");

namespace ns3 {

const uint16_t Ipv4L3Protocol::PROT_NUMBER = 0x0800;

NS_OBJECT_ENSURE_REGISTERED (Ipv4L3Protocol);

TypeId 

Ipv4L3Protocol::GetTypeId (void)

{

  static TypeId tid = TypeId ("ns3::Ipv4L3Protocol")

    .SetParent<Ipv4> ()

    .AddConstructor<Ipv4L3Protocol> ()

    .AddAttribute ("DefaultTtl", "The TTL value set by default on all outgoing packets generated on this node.",

                   UintegerValue (64),

                   MakeUintegerAccessor (&Ipv4L3Protocol::m_defaultTtl),

                   MakeUintegerChecker<uint8_t> ())

    .AddTraceSource ("Tx", "Send ipv4 packet to outgoing interface.",

                   MakeTraceSourceAccessor (&Ipv4L3Protocol::m_txTrace))

    .AddTraceSource ("Rx", "Receive ipv4 packet from incoming interface.",

                     MakeTraceSourceAccessor (&Ipv4L3Protocol::m_rxTrace))

    .AddTraceSource ("Drop", "Drop ipv4 packet",

                     MakeTraceSourceAccessor (&Ipv4L3Protocol::m_dropTrace))

    .AddAttribute ("InterfaceList", "The set of Ipv4 interfaces associated to this Ipv4 stack.",

                   ObjectVectorValue (),

                   MakeObjectVectorAccessor (&Ipv4L3Protocol::m_interfaces),

                   MakeObjectVectorChecker<Ipv4Interface> ())

    ;

  return tid;

}

uint32_t NfPreRoutingHookFunction (Hooks_t hookNumber, Ptr<Packet> p, Ptr<NetDevice> in, Ptr<NetDevice> out, ContinueCallback& ccb)

{

  std::cout << "NfPreRoutingHookFunction called at node " << in->GetNode () << " at NF_PRE_ROUTING" << std::endl;

  Ipv4Header ipHeader;

  p->PeekHeader (ipHeader);

  if (ipHeader.GetProtocol () == 6 /* TCP */ )

    std::cout << "This is a TCP packet at node " << in->GetNode () << std::endl;

  else if (ipHeader.GetProtocol () == 17 /* UDP */ )

    std::cout << "This is a UDP packet at node " << in->GetNode () << std::endl;

  //p->Print (std::cout);

  //std::cout<<std::endl;

  return 0;

}

uint32_t NfPostRoutingHookFunction (Hooks_t hookNumber, Ptr<Packet> p, Ptr<NetDevice> in, Ptr<NetDevice> out, ContinueCallback& ccb)

{

  std::cout << "NfPostRoutingHookFunction called at node " << out->GetNode () << " at NF_POST_ROUTING" << std::endl;

  Ipv4Header ipHeader;

  p->PeekHeader (ipHeader);

  if (ipHeader.GetProtocol () == 6 /* TCP */ )

    std::cout << "This is a TCP packet at node " << out->GetNode () << std::endl;

  else if (ipHeader.GetProtocol () == 17 /* UDP */ )

    std::cout << "This is a UDP packet at node " << out->GetNode () << std::endl;

  //p->Print (std::cout);

  //std::cout<<std::endl;

  return 0;

}

Ipv4L3Protocol::Ipv4L3Protocol ()

  : m_nInterfaces (0),

    m_identification (0)

{

  NS_LOG_FUNCTION_NOARGS ();

  /*NetfilterHookCallback nhc = MakeCallback(&NfPreRoutingHookFunction);

  NetfilterHookCallback nhc2 = MakeCallback(&NfPostRoutingHookFunction);

  Ipv4NetfilterHook nfh = Ipv4NetfilterHook(1, NF_INET_PRE_ROUTING, 2, nhc); 

  Ipv4NetfilterHook nfh2 = Ipv4NetfilterHook(1, NF_INET_POST_ROUTING, 2, nhc2); 

  netfilter.RegisterNetfilterHook(nfh);

  netfilter.RegisterNetfilterHook(nfh2);*/

}

Ipv4L3Protocol::~Ipv4L3Protocol ()

{

  NS_LOG_FUNCTION (this);

}

void

Ipv4L3Protocol::Insert(Ptr<Ipv4L4Protocol> protocol)

{

  m_protocols.push_back (protocol);

}

Ptr<Ipv4L4Protocol>

Ipv4L3Protocol::GetProtocol (int protocolNumber) const

{

  for (L4List_t::const_iterator i = m_protocols.begin (); i != m_protocols.end (); ++i)

    {

      if ((*i)->GetProtocolNumber () == protocolNumber)

	{

	  return *i;

	}

    }

  return 0;

}

void

Ipv4L3Protocol::Remove (Ptr<Ipv4L4Protocol> protocol)

{

  m_protocols.remove (protocol);

}

void

Ipv4L3Protocol::SetNode (Ptr<Node> node)

{

  m_node = node;

  // Add a LoopbackNetDevice if needed, and an Ipv4Interface on top of it

  SetupLoopback ();

}

Ptr<Socket> 

Ipv4L3Protocol::CreateRawSocket (void)

{

  NS_LOG_FUNCTION (this);

  Ptr<Ipv4RawSocketImpl> socket = CreateObject<Ipv4RawSocketImpl> ();

  socket->SetNode (m_node);

  m_sockets.push_back (socket);

  return socket;

}

void 

Ipv4L3Protocol::DeleteRawSocket (Ptr<Socket> socket)

{

  NS_LOG_FUNCTION (this << socket);

  for (SocketList::iterator i = m_sockets.begin (); i != m_sockets.end (); ++i)

    {

      if ((*i) == socket)

        {

          m_sockets.erase (i);

          return;

        }

    }

  return;

}

/*

 * This method is called by AddAgregate and completes the aggregation

 * by setting the node in the ipv4 stack

 */

void

Ipv4L3Protocol::NotifyNewAggregate ()

{

  Ptr<Node>node = this->GetObject<Node>();

  // verify that it's a valid node and that

  // the node has not been set before

  if (node!= 0 && m_node == 0)

    {

      this->SetNode (node);

    }

  Object::NotifyNewAggregate ();

}

void 

Ipv4L3Protocol::SetRoutingProtocol (Ptr<Ipv4RoutingProtocol> routingProtocol)

{

  NS_LOG_FUNCTION (this);

  m_routingProtocol = routingProtocol;

  m_routingProtocol->SetIpv4 (this);

}

Ptr<Ipv4RoutingProtocol> 

Ipv4L3Protocol::GetRoutingProtocol (void) const

{

  return m_routingProtocol;

}

void 

Ipv4L3Protocol::DoDispose (void)

{

  NS_LOG_FUNCTION (this);

  for (L4List_t::iterator i = m_protocols.begin (); i != m_protocols.end (); ++i)

    {

      *i = 0;

    }

  m_protocols.clear ();

  for (Ipv4InterfaceList::iterator i = m_interfaces.begin (); i != m_interfaces.end (); ++i)

    {

      *i = 0;

    }

  m_interfaces.clear ();

  m_node = 0;

  m_routingProtocol = 0;

  Object::DoDispose ();

}

void

Ipv4L3Protocol::SetupLoopback (void)

{

  NS_LOG_FUNCTION_NOARGS ();

  Ptr<Ipv4Interface> interface = CreateObject<Ipv4Interface> ();

  Ptr<LoopbackNetDevice> device = 0;

  // First check whether an existing LoopbackNetDevice exists on the node

  for (uint32_t i = 0; i < m_node->GetNDevices (); i++)

    {

      if (device = DynamicCast<LoopbackNetDevice> (m_node->GetDevice (i)))

        {

          break;

        }

    }

  if (device == 0)

    {

      device = CreateObject<LoopbackNetDevice> (); 

      m_node->AddDevice (device);

    }

  interface->SetDevice (device);

  interface->SetNode (m_node);

  Ipv4InterfaceAddress ifaceAddr = Ipv4InterfaceAddress (Ipv4Address::GetLoopback (), Ipv4Mask::GetLoopback ());

  interface->AddAddress (ifaceAddr);

  uint32_t index = AddIpv4Interface (interface);

  Ptr<Node> node = GetObject<Node> ();

  node->RegisterProtocolHandler (MakeCallback (&Ipv4L3Protocol::Receive, this), 

                                 Ipv4L3Protocol::PROT_NUMBER, device);

  interface->SetUp ();

  if (m_routingProtocol != 0)

    {

      m_routingProtocol->NotifyInterfaceUp (index);

    }

}

void 

Ipv4L3Protocol::SetDefaultTtl (uint8_t ttl)

{

  NS_LOG_FUNCTION_NOARGS ();

  m_defaultTtl = ttl;

}

uint32_t 

Ipv4L3Protocol::AddInterface (Ptr<NetDevice> device)

{

  NS_LOG_FUNCTION (this << &device);

  Ptr<Node> node = GetObject<Node> ();

  node->RegisterProtocolHandler (MakeCallback (&Ipv4L3Protocol::Receive, this), 

                                 Ipv4L3Protocol::PROT_NUMBER, device);

  node->RegisterProtocolHandler (MakeCallback (&ArpL3Protocol::Receive, PeekPointer (GetObject<ArpL3Protocol> ())),

                                 ArpL3Protocol::PROT_NUMBER, device);

  Ptr<Ipv4Interface> interface = CreateObject<Ipv4Interface> ();

  interface->SetNode (m_node);

  interface->SetDevice (device);

  interface->SetForwarding (m_ipForward);

  return AddIpv4Interface (interface);

}

uint32_t 

Ipv4L3Protocol::AddIpv4Interface (Ptr<Ipv4Interface>interface)

{

  NS_LOG_FUNCTION (this << interface);

  uint32_t index = m_nInterfaces;

  m_interfaces.push_back (interface);

  m_nInterfaces++;

  return index;

}

Ptr<Ipv4Interface>

Ipv4L3Protocol::GetInterface (uint32_t index) const

{

  NS_LOG_FUNCTION (this << index);

  uint32_t tmp = 0;

  for (Ipv4InterfaceList::const_iterator i = m_interfaces.begin (); i != m_interfaces.end (); i++)

    {

      if (index == tmp) 

	{

	  return *i;

	}

      tmp++;

    }

  return 0;

}

uint32_t 

Ipv4L3Protocol::GetNInterfaces (void) const

{

  NS_LOG_FUNCTION_NOARGS ();

  return m_nInterfaces;

}

int32_t 

Ipv4L3Protocol::GetInterfaceForAddress (

  Ipv4Address address) const

{

  NS_LOG_FUNCTION (this << address);

  int32_t interface = 0;

  for (Ipv4InterfaceList::const_iterator i = m_interfaces.begin (); 

       i != m_interfaces.end (); 

       i++, interface++)

    {

      for (uint32_t j = 0; j < (*i)->GetNAddresses (); j++)

        {

          if ((*i)->GetAddress (j).GetLocal () == address)

            {

              return interface;

            }

        }

    }

  return -1;

}

int32_t 

Ipv4L3Protocol::GetInterfaceForPrefix (

  Ipv4Address address, 

  Ipv4Mask mask) const

{

  NS_LOG_FUNCTION (this << address << mask);

  int32_t interface = 0;

  for (Ipv4InterfaceList::const_iterator i = m_interfaces.begin (); 

       i != m_interfaces.end (); 

       i++, interface++)

    {

      for (uint32_t j = 0; j < (*i)->GetNAddresses (); j++)

        {

          if ((*i)->GetAddress (j).GetLocal ().CombineMask (mask) == address.CombineMask (mask))

            {

              return interface;

            }

        }

    }

  return -1;

}

int32_t 

Ipv4L3Protocol::GetInterfaceForDevice (

  Ptr<const NetDevice> device) const

{

  NS_LOG_FUNCTION (this << device->GetIfIndex());

  int32_t interface = 0;

  for (Ipv4InterfaceList::const_iterator i = m_interfaces.begin (); 

       i != m_interfaces.end (); 

       i++, interface++)

    {

      if ((*i)->GetDevice () == device)

        {

          return interface;

        }

    }

  return -1;

}

void 

Ipv4L3Protocol::Receive( Ptr<NetDevice> device, Ptr<const Packet> p, uint16_t protocol, const Address &from,

                         const Address &to, NetDevice::PacketType packetType)

{

  NS_LOG_FUNCTION (this << &device << p << protocol <<  from);

  NS_LOG_LOGIC ("Packet from " << from << " received on node " << 

    m_node->GetId ());

  uint32_t interface = 0;

  Ptr<Packet> packet = p->Copy ();

  // TODO: Netfilter

  NS_LOG_DEBUG ("NF_INET_PRE_ROUTING Hook");

  netfilter.ProcessHook ((uint8_t)1, NF_INET_PRE_ROUTING, packet, device, device);

  Ptr<Ipv4Interface> ipv4Interface;

  for (Ipv4InterfaceList::const_iterator i = m_interfaces.begin (); 

       i != m_interfaces.end (); 

       i++)

    {

      ipv4Interface = *i;

      if (ipv4Interface->GetDevice () == device)

        {

          if (ipv4Interface->IsUp ())

            {

              m_rxTrace (packet, interface);

              break;

            }

          else

            {

              NS_LOG_LOGIC ("Dropping received packet-- interface is down");

              m_dropTrace (packet);

              return;

            }

        }

      interface++;

    }

  Ipv4Header ipHeader;

  if (Node::ChecksumEnabled ())

    {

      ipHeader.EnableChecksum ();

    }

  packet->RemoveHeader (ipHeader);

  if (!ipHeader.IsChecksumOk ()) 

    {

      m_dropTrace (packet);

      return;

    }

  for (SocketList::iterator i = m_sockets.begin (); i != m_sockets.end (); ++i)

    {

      Ptr<Ipv4RawSocketImpl> socket = *i;

      socket->ForwardUp (packet, ipHeader, device);

    }

  m_routingProtocol->RouteInput (packet, ipHeader, device, 

    MakeCallback (&Ipv4L3Protocol::IpForward, this),

    MakeCallback (&Ipv4L3Protocol::IpMulticastForward, this),

    MakeCallback (&Ipv4L3Protocol::LocalDeliver, this),

    MakeCallback (&Ipv4L3Protocol::RouteInputError, this)

  );

}

Ptr<Icmpv4L4Protocol> 

Ipv4L3Protocol::GetIcmp (void) const

{

  Ptr<Ipv4L4Protocol> prot = GetProtocol (Icmpv4L4Protocol::GetStaticProtocolNumber ());

  if (prot != 0)

    {

      return prot->GetObject<Icmpv4L4Protocol> ();

    }

  else

    {

      return 0;

    }

}

bool

Ipv4L3Protocol::IsUnicast (Ipv4Address ad, Ipv4Mask interfaceMask) const

{

  return !ad.IsMulticast () && !ad.IsSubnetDirectedBroadcast (interfaceMask);

}

void 

Ipv4L3Protocol::Send (Ptr<Packet> packet, 

            Ipv4Address source, 

            Ipv4Address destination,

            uint8_t protocol,

            Ptr<Ipv4Route> route)

{

  NS_LOG_FUNCTION (this << packet << source << destination << uint32_t(protocol) << route);

  Ipv4Header ipHeader;

  bool mayFragment = true;

  uint8_t ttl = m_defaultTtl;

  SocketIpTtlTag tag;

  Ptr<NetDevice> outDev;

  if (!route) 

  {

    std::cout<< "Route: " << *route << std::endl;

    outDev = route->GetOutputDevice ();

  }

  // Netfilter LOCAL_OUT Hook

  //Ptr<Packet> packetCopy = packet->Copy ();

  bool found = packet->RemovePacketTag (tag);

  if (found)

    {

      ttl = tag.GetTtl ();

    }

  // Handle a few cases:

  // 1) packet is destined to limited broadcast address

  // 2) packet is destined to a subnet-directed broadcast address

  // 3) packet is not broadcast, and is passed in with a route entry

  // 4) packet is not broadcast, and is passed in with a route entry but route->GetGateway is not set (e.g., on-demand)

  // 5) packet is not broadcast, and route is NULL (e.g., a raw socket call, or ICMP)

  // 1) packet is destined to limited broadcast address

  if (destination.IsBroadcast ()) 

    {

      NS_LOG_LOGIC ("Ipv4L3Protocol::Send case 1:  limited broadcast");

      ttl = 1;

      ipHeader = BuildHeader (source, destination, protocol, packet->GetSize (), ttl, mayFragment);

      uint32_t ifaceIndex = 0;

      for (Ipv4InterfaceList::iterator ifaceIter = m_interfaces.begin ();

           ifaceIter != m_interfaces.end (); ifaceIter++, ifaceIndex++)

      {

        Ptr<Ipv4Interface> outInterface = *ifaceIter;

        Ptr<Packet> packetCopy = packet->Copy ();

        NS_ASSERT (packetCopy->GetSize () <= outInterface->GetDevice()->GetMtu ());

        packetCopy->AddHeader (ipHeader);

        /*NS_LOG_DEBUG ("NF_INET_LOCAL_OUT Hook");

        netfilter.ProcessHook ((uint8_t)1, NF_INET_LOCAL_OUT, packetCopy, outDev, outDev);*/

        NS_LOG_DEBUG ("NF_INET_POST_ROUTING Hook");

        Callback<uint32_t, Ptr<Packet> > ccb = MakeCallback (&Ipv4Netfilter::NetfilterConntrackConfirm, &netfilter);

        netfilter.ProcessHook ((uint8_t)1, NF_INET_POST_ROUTING, packetCopy, outDev, outDev, ccb);

        m_txTrace (packetCopy, ifaceIndex);

        outInterface->Send (packetCopy, destination);

      }

      return;

    }

  // 2) check: packet is destined to a subnet-directed broadcast address

  uint32_t ifaceIndex = 0;

  for (Ipv4InterfaceList::iterator ifaceIter = m_interfaces.begin ();

    ifaceIter != m_interfaces.end (); ifaceIter++, ifaceIndex++)

    {

      Ptr<Ipv4Interface> outInterface = *ifaceIter;

      for (uint32_t j = 0; j < GetNAddresses (ifaceIndex); j++)

        {

          Ipv4InterfaceAddress ifAddr = GetAddress (ifaceIndex, j);

          NS_LOG_LOGIC ("Testing address " << ifAddr.GetLocal () << " with mask " << ifAddr.GetMask ());

          if (destination.IsSubnetDirectedBroadcast (ifAddr.GetMask ()) && 

              destination.CombineMask (ifAddr.GetMask ()) == ifAddr.GetLocal ().CombineMask (ifAddr.GetMask ())   )  

          {

            NS_LOG_LOGIC ("Ipv4L3Protocol::Send case 2:  subnet directed bcast to " << ifAddr.GetLocal ());

            ttl = 1;

            ipHeader = BuildHeader (source, destination, protocol, packet->GetSize (), ttl, mayFragment);

            Ptr<Packet> packetCopy = packet->Copy ();

            packetCopy->AddHeader (ipHeader);

            /*NS_LOG_DEBUG ("NF_INET_LOCAL_OUT Hook");

            netfilter.ProcessHook ((uint8_t)1, NF_INET_LOCAL_OUT, packetCopy, outDev, outDev);*/

            NS_LOG_DEBUG ("NF_INET_POST_ROUTING Hook");

            Callback<uint32_t, Ptr<Packet> > ccb = MakeCallback (&Ipv4Netfilter::NetfilterConntrackConfirm, &netfilter);

            netfilter.ProcessHook ((uint8_t)1, NF_INET_POST_ROUTING, packetCopy, outDev, outDev, ccb);

            m_txTrace (packetCopy, ifaceIndex);

            outInterface->Send (packetCopy, destination);

            return;

          }

        }

    }

  // 3) packet is not broadcast, and is passed in with a route entry

  //    with a valid Ipv4Address as the gateway

  if (route && route->GetGateway () != Ipv4Address ())

  {

    NS_LOG_LOGIC ("Ipv4L3Protocol::Send case 3:  passed in with route");

    Ptr<Packet> packetCopy = packet->Copy ();

    NS_LOG_DEBUG ("NF_INET_LOCAL_OUT Hook");

    ipHeader = BuildHeader (source, destination, protocol, packetCopy->GetSize (), ttl, mayFragment);

    packetCopy->AddHeader (ipHeader);

    NS_LOG_DEBUG (" :: Add Ipv4 Header :: ");

    netfilter.ProcessHook ((uint8_t)1, NF_INET_LOCAL_OUT, packetCopy, outDev, outDev);

    NS_LOG_DEBUG (" :: Remove Ipv4 Header :: ");

    packetCopy->RemoveHeader (ipHeader);

    SendRealOut (route, packetCopy, ipHeader);

    return; 

  } 

  // 4) packet is not broadcast, and is passed in with a route entry but route->GetGateway is not set (e.g., on-demand)

  if (route && route->GetGateway () != Ipv4Address ())

    {

      // This could arise because the synchronous RouteOutput() call

      // returned to the transport protocol with a source address but

      // there was no next hop available yet (since a route may need

      // to be queried).  

      NS_FATAL_ERROR ("This case not yet implemented");

    }

  // 5) packet is not broadcast, and route is NULL (e.g., a raw socket call)

  NS_LOG_LOGIC ("Ipv4L3Protocol::Send case 4:  passed in with no route " << destination);

  Ptr<Packet> packetCopy = packet->Copy ();

  Socket::SocketErrno errno_; 

  uint32_t oif = 0; // unused for now

  ipHeader = BuildHeader (source, destination, protocol, packet->GetSize (), ttl, mayFragment);

  NS_LOG_DEBUG (" :: Add Ipv4 Header :: ");

  packetCopy->AddHeader (ipHeader);

  NS_LOG_DEBUG ("NF_INET_LOCAL_OUT Hook");

  netfilter.ProcessHook ((uint8_t)1, NF_INET_LOCAL_OUT, packetCopy, outDev, outDev);

  NS_LOG_DEBUG (" :: Remove Ipv4 Header :: ");

  packetCopy->RemoveHeader (ipHeader);

  Ptr<Ipv4Route> newRoute = m_routingProtocol->RouteOutput (packet, ipHeader, oif, errno_);

  if (newRoute)

    {

      SendRealOut (newRoute, packet, ipHeader);

    }

  else

    {

      NS_LOG_WARN ("No route to host.  Drop.");

      m_dropTrace (packet);

    }

}

// XXX when should we set ip_id?   check whether we are incrementing

// m_identification on packets that may later be dropped in this stack

// and whether that deviates from Linux

Ipv4Header

Ipv4L3Protocol::BuildHeader (

            Ipv4Address source, 

            Ipv4Address destination,

            uint8_t protocol,

            uint16_t payloadSize,

            uint8_t ttl,

            bool mayFragment)

{

  NS_LOG_FUNCTION_NOARGS ();

  Ipv4Header ipHeader;

  ipHeader.SetSource (source);

  ipHeader.SetDestination (destination);

  ipHeader.SetProtocol (protocol);

  ipHeader.SetPayloadSize (payloadSize);

  ipHeader.SetTtl (ttl);

  if (mayFragment == true)

    {

      ipHeader.SetMayFragment ();

      ipHeader.SetIdentification (m_identification);

      m_identification ++;

    }

  else

    {

      ipHeader.SetDontFragment ();

      // TBD:  set to zero here; will cause traces to change

      ipHeader.SetIdentification (m_identification);

      m_identification ++;

    }

  if (Node::ChecksumEnabled ())

    {

      ipHeader.EnableChecksum ();

    }

  return ipHeader;

}

void

Ipv4L3Protocol::SendRealOut (Ptr<Ipv4Route> route,

                             Ptr<Packet> packet,

                             Ipv4Header const &ipHeader)

{

  NS_LOG_FUNCTION (this << packet << &ipHeader);

  Ptr<NetDevice> outDev = route->GetOutputDevice ();

  // We add a header regardless of whether there is a route, since 

  // we may want to drop trace

  packet->AddHeader (ipHeader);

  Callback<uint32_t, Ptr<Packet> > ccb = MakeCallback (&Ipv4Netfilter::NetfilterConntrackConfirm, &netfilter);

  NS_LOG_DEBUG ("NF_INET_POST_ROUTING Hook");

  netfilter.ProcessHook ((uint8_t)1, NF_INET_POST_ROUTING, packet, outDev, outDev, ccb);

  if (route == 0)

    {

      NS_LOG_WARN ("No route to host.  Drop.");

      m_dropTrace (packet);

      return;

    }

  int32_t interface = GetInterfaceForDevice (outDev);

  NS_ASSERT (interface >= 0);

  Ptr<Ipv4Interface> outInterface = GetInterface (interface);

  NS_LOG_LOGIC ("Send via NetDevice ifIndex " << outDev->GetIfIndex () << " ipv4InterfaceIndex " << interface);

  NS_ASSERT (packet->GetSize () <= outInterface->GetDevice ()->GetMtu ());

  if (!route->GetGateway ().IsEqual (Ipv4Address ("0.0.0.0"))) 

    {

      if (outInterface->IsUp ())

        {

          NS_LOG_LOGIC ("Send to gateway " << route->GetGateway ());

          m_txTrace (packet, interface);

          outInterface->Send (packet, route->GetGateway ());

        }

      else

        {

          NS_LOG_LOGIC ("Dropping-- outgoing interface is down: " << route->GetGateway ());

          m_dropTrace (packet);

        }

    } 

  else 

    {

      if (outInterface->IsUp ())

        {

          NS_LOG_LOGIC ("Send to destination " << ipHeader.GetDestination ());

          m_txTrace (packet, interface);

          outInterface->Send (packet, ipHeader.GetDestination ());

        }

      else

        {

          NS_LOG_LOGIC ("Dropping-- outgoing interface is down: " << ipHeader.GetDestination ());

          m_dropTrace (packet);

        }

    }

}

// This function analogous to Linux ip_mr_forward()

void

Ipv4L3Protocol::IpMulticastForward (Ptr<Ipv4MulticastRoute> mrtentry, Ptr<const Packet> p, const Ipv4Header &header)

{

  NS_LOG_FUNCTION (mrtentry << p << header);

  NS_LOG_LOGIC ("Multicast forwarding logic for node: " << m_node->GetId ());

  // The output interfaces we could forward this onto are encoded

  // in the OutputTtl of the Ipv4MulticastRoute

  for (uint32_t i = 0; i < Ipv4MulticastRoute::MAX_INTERFACES; i++)

    {

      if (mrtentry->GetOutputTtl (i) < Ipv4MulticastRoute::MAX_TTL)

        {

          Ptr<Packet> packet = p->Copy ();

          Ipv4Header h = header;

          h.SetTtl (header.GetTtl () - 1);

          if (h.GetTtl () == 0)

            {

              NS_LOG_WARN ("TTL exceeded.  Drop.");

              m_dropTrace (packet);

              return;

            }

          NS_LOG_LOGIC ("Forward multicast via interface " << i);

          Ptr<Ipv4Route> rtentry = Create<Ipv4Route> ();

          rtentry->SetSource (h.GetSource ());

          rtentry->SetDestination (h.GetDestination ());

          rtentry->SetGateway (Ipv4Address::GetAny ());

          rtentry->SetOutputDevice (GetNetDevice (i));

          SendRealOut (rtentry, packet, h);

          return; 

        }

    }

}

// This function analogous to Linux ip_forward()

void

Ipv4L3Protocol::IpForward (Ptr<Ipv4Route> rtentry, Ptr<const Packet> p, const Ipv4Header &header)

{

  NS_LOG_FUNCTION (rtentry << p << header);

  NS_LOG_LOGIC ("Forwarding logic for node: " << m_node->GetId ());

  // Forwarding

  Ipv4Header ipHeader = header;

  Ptr<Packet> packet = p->Copy ();

  Ptr<NetDevice> outDev = rtentry->GetOutputDevice ();

  ipHeader.SetTtl (ipHeader.GetTtl () - 1);

  if (ipHeader.GetTtl () == 0)

    {

      // Do not reply to ICMP or to multicast/broadcast IP address 

      if (ipHeader.GetProtocol () != Icmpv4L4Protocol::PROT_NUMBER && 

        ipHeader.GetDestination ().IsBroadcast () == false && 

        ipHeader.GetDestination ().IsMulticast () == false)

        {

          Ptr<Icmpv4L4Protocol> icmp = GetIcmp ();

          icmp->SendTimeExceededTtl (ipHeader, packet);

        }

      NS_LOG_WARN ("TTL exceeded.  Drop.");

      m_dropTrace (packet);

      return;

    }

  // Netfilter FORWARD Hook

  NS_LOG_DEBUG ("NF_INET_FORWARD Hook");

  netfilter.ProcessHook ((uint8_t)1, NF_INET_FORWARD, packet, outDev, outDev);

  SendRealOut (rtentry, packet, ipHeader);

}

void

Ipv4L3Protocol::LocalDeliver (Ptr<const Packet> packet, Ipv4Header const&ip, uint32_t iif)

{

  NS_LOG_FUNCTION (this << packet << &ip);

  Ptr<Packet> pkt = packet->Copy (); // need to pass a non-const packet up

  // Netfilter LOCAL_IN Hook

  Ptr<NetDevice> device;

  pkt->AddHeader(ip);

  Callback<uint32_t, Ptr<Packet> > ccb = MakeCallback (&Ipv4Netfilter::NetfilterConntrackConfirm, &netfilter);

  NS_LOG_DEBUG ("NF_INET_LOCAL_IN Hook");

  netfilter.ProcessHook ((uint8_t)1, NF_INET_LOCAL_IN, pkt, device, device, ccb);

  Ptr<Packet> p = packet->Copy (); // need to pass a non-const packet up

  //p->RemoveHeader(ip);

  Ptr<Ipv4L4Protocol> protocol = GetProtocol (ip.GetProtocol ());

  if (protocol != 0)

    {

      // we need to make a copy in the unlikely event we hit the

      // RX_ENDPOINT_UNREACH codepath

      Ptr<Packet> copy = p->Copy ();

      enum Ipv4L4Protocol::RxStatus status = 

        protocol->Receive (p, ip.GetSource (), ip.GetDestination (), GetInterface (iif));

      switch (status) {

      case Ipv4L4Protocol::RX_OK:

        // fall through

      case Ipv4L4Protocol::RX_CSUM_FAILED:

        break;

      case Ipv4L4Protocol::RX_ENDPOINT_UNREACH:

        if (ip.GetDestination ().IsBroadcast () == true || 

          ip.GetDestination ().IsMulticast () == true)

          {

            break;  // Do not reply to broadcast or multicast

          }

        // Another case to suppress ICMP is a subnet-directed broadcast

        bool subnetDirected = false;

        for (uint32_t i = 0; i < GetNAddresses (iif); i++)

          {

            Ipv4InterfaceAddress addr = GetAddress (iif, i);

            if (addr.GetLocal ().CombineMask (addr.GetMask ()) == ip.GetDestination ().CombineMask (addr.GetMask ()) &&

              ip.GetDestination ().IsSubnetDirectedBroadcast (addr.GetMask ()))

              {

                subnetDirected = true;

              }

          }

        if (subnetDirected == false)

          {

            GetIcmp ()->SendDestUnreachPort (ip, copy);

          }

      }

    }

}

bool

Ipv4L3Protocol::AddAddress (uint32_t i, Ipv4InterfaceAddress address)

{

  NS_LOG_FUNCTION (this << i << address);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  bool retVal = interface->AddAddress (address);

  if (m_routingProtocol != 0)

    {

      m_routingProtocol->NotifyAddAddress (i, address);

    }

  return retVal;

}

Ipv4InterfaceAddress 

Ipv4L3Protocol::GetAddress (uint32_t interfaceIndex, uint32_t addressIndex) const

{

  NS_LOG_FUNCTION (this << interfaceIndex << addressIndex);

  Ptr<Ipv4Interface> interface = GetInterface (interfaceIndex);

  return interface->GetAddress (addressIndex);

}

uint32_t 

Ipv4L3Protocol::GetNAddresses (uint32_t interface) const

{

  NS_LOG_FUNCTION (this << interface);

  Ptr<Ipv4Interface> iface = GetInterface (interface);

  return iface->GetNAddresses ();

}

bool

Ipv4L3Protocol::RemoveAddress (uint32_t i, uint32_t addressIndex)

{

  NS_LOG_FUNCTION (this << i << addressIndex);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  Ipv4InterfaceAddress address = interface->RemoveAddress (addressIndex);

  if (address != Ipv4InterfaceAddress ())

    {

      if (m_routingProtocol != 0)

        {

          m_routingProtocol->NotifyRemoveAddress (i, address);

        }

      return true;

    }

  return false;

}

void 

Ipv4L3Protocol::SetMetric (uint32_t i, uint16_t metric)

{

  NS_LOG_FUNCTION (i << metric);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  interface->SetMetric (metric);

}

uint16_t

Ipv4L3Protocol::GetMetric (uint32_t i) const

{

  NS_LOG_FUNCTION (i);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  return interface->GetMetric ();

}

uint16_t 

Ipv4L3Protocol::GetMtu (uint32_t i) const

{

  NS_LOG_FUNCTION (this << i);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  return interface->GetDevice ()->GetMtu ();

}

bool 

Ipv4L3Protocol::IsUp (uint32_t i) const

{

  NS_LOG_FUNCTION (this << i);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  return interface->IsUp ();

}

void 

Ipv4L3Protocol::SetUp (uint32_t i)

{

  NS_LOG_FUNCTION (this << i);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  interface->SetUp ();

  if (m_routingProtocol != 0)

    {

      m_routingProtocol->NotifyInterfaceUp (i);

    }

}

void 

Ipv4L3Protocol::SetDown (uint32_t ifaceIndex)

{

  NS_LOG_FUNCTION (this << ifaceIndex);

  Ptr<Ipv4Interface> interface = GetInterface (ifaceIndex);

  interface->SetDown ();

  if (m_routingProtocol != 0)

    {

      m_routingProtocol->NotifyInterfaceDown (ifaceIndex);

    }

}

bool 

Ipv4L3Protocol::IsForwarding (uint32_t i) const

{

  NS_LOG_FUNCTION (this << i);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  NS_LOG_LOGIC ("Forwarding state: " << interface->IsForwarding ());

  return interface->IsForwarding ();

}

void 

Ipv4L3Protocol::SetForwarding (uint32_t i, bool val)

{

  NS_LOG_FUNCTION (this << i);

  Ptr<Ipv4Interface> interface = GetInterface (i);

  interface->SetForwarding (val);

}

Ptr<NetDevice>

Ipv4L3Protocol::GetNetDevice (uint32_t i)

{

  NS_LOG_FUNCTION (this << i);

  return GetInterface (i)-> GetDevice ();

}

void 

Ipv4L3Protocol::SetIpForward (bool forward) 

{

  NS_LOG_FUNCTION (this << forward);

  m_ipForward = forward;

  for (Ipv4InterfaceList::const_iterator i = m_interfaces.begin (); i != m_interfaces.end (); i++)

    {

      (*i)->SetForwarding (forward);

    }

}

bool 

Ipv4L3Protocol::GetIpForward (void) const