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

     2 /*

     3  * Copyright (c) 2008 INRIA

     4  *

     5  * This program is free software; you can redistribute it and/or modify

     6  * it under the terms of the GNU General Public License version 2 as

     7  * published by the Free Software Foundation;

     8  *

     9  * This program is distributed in the hope that it will be useful,

    10  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    12  * GNU General Public License for more details.

    13  *

    14  * You should have received a copy of the GNU General Public License

    15  * along with this program; if not, write to the Free Software

    16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    17  *

    18  * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

    19  */

    20 #include "tap-net-device.h"

    21 #include "tap-manager-client.h"

    22 #include "ns3/node.h"

    23 #include "ns3/channel.h"

    24 #include "ns3/packet.h"

    25 #include "ns3/log.h"

    26 #include "ns3/system-thread.h"

    27 #include "ns3/realtime-simulator-impl.h"

    28 #include "ns3/make-event.h"

    29 #include "ns3/simulator.h"

    30 #include "ns3/ethernet-header.h"

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

    32 #include "host-tap-net-device.h"

    33 #include "tap-channel.h"

    34 #include <errno.h>

    35 #include <stdlib.h>

    36 

    37 NS_LOG_COMPONENT_DEFINE ("TapNetDevice");

    38 

    39 namespace ns3 {

    40 

    41 TypeId 

    42 TapNetDevice::GetTypeId (void)

    43 {

    44   static TypeId tid = TypeId ("ns3::TapNetDevice")

    45     .SetParent<NetDevice> ()

    46     .AddConstructor<TapNetDevice> ()

    47     .AddTraceSource ("Rx", "A packet has been received",

    48                      MakeTraceSourceAccessor (&TapNetDevice::m_rxTrace))

    49     .AddTraceSource ("Tx", "A packet has been sent",

    50                      MakeTraceSourceAccessor (&TapNetDevice::m_txTrace))

    51     .AddTraceSource ("Drop", "A packet has been dropped",

    52                      MakeTraceSourceAccessor (&TapNetDevice::m_dropTrace))

    53     ;

    54   return tid;

    55 }

    56 

    57 TapNetDevice::TapNetDevice ()

    58   : m_node (0),

    59     m_mtu (0xffff),

    60     m_name (""),

    61     m_ifIndex (0),

    62     m_tap (-1)

    63 {

    64   NS_LOG_FUNCTION (this);

    65 }

    66 

    67 void 

    68 TapNetDevice::SetChannel (Ptr<TapChannel> channel)

    69 {

    70   m_channel = channel;

    71   m_channel->SetDevice (this);

    72 }

    73 

    74 void 

    75 TapNetDevice::SetupHost (Ipv4Address ad, Ipv4Mask mask, Ipv4Address gateway)

    76 {

    77   NS_LOG_FUNCTION (this << ad << mask << gateway);

    78   NS_ASSERT (m_tap == -1);

    79 

    80   Mac48Address hostMacAddress = m_channel->GetHostDevice ()->GetMacAddress ();

    81 

    82   TapManagerClient manager;

    83   m_tap = manager.AllocateTap (hostMacAddress, ad, mask, gateway);

    84 

    85   m_thread = Create<SystemThread> (MakeCallback (&TapNetDevice::ReadThread, this));

    86   m_thread->Start ();

    87 }

    88 

    89 

    90 void

    91 TapNetDevice::ReadThread (void)

    92 {

    93   NS_LOG_FUNCTION (this);

    94 

    95   while (1)

    96     {

    97       uint8_t *buffer = (uint8_t *)malloc (0xffff);

    98       ssize_t bytesRead = read (m_tap, buffer, 0xffff);

    99       if (bytesRead == -1)

   100         {

   101           if (errno == EBADF || errno == EINTR)

   102             {

   103               // the device was closed from under us by ::DoDispose

   104               return;

   105             }

   106           NS_FATAL_ERROR ("Error reading from tap device: errno=" << strerror (errno));

   107         }

   108       // Note: we purposedly don't use a smart pointer to manage this packet

   109       // because the want to hand over ownership of this packet to the ForwardUp

   110       // method.

   111       DynamicCast<RealtimeSimulatorImpl> (Simulator::GetImplementation ())->

   112         ScheduleRealtimeNow (MakeEvent (&TapNetDevice::ForwardUp, this, buffer, (uint32_t)bytesRead));

   113     }

   114 }

   115 

   116 void

   117 TapNetDevice::ForwardUp (uint8_t *buffer, uint32_t size)

   118 {

   119   NS_LOG_FUNCTION (this << buffer << size);

   120 

   121   // swallow packet reference in smart pointer.

   122   Ptr<Packet> packet = Create<Packet> (buffer, size);

   123   free (buffer);

   124   Ptr<Packet> copy = packet->Copy ();

   125 

   126   EthernetHeader header = EthernetHeader (false);

   127   packet->RemoveHeader (header);

   128 

   129   uint16_t protocol = header.GetLengthType ();

   130   Mac48Address to = header.GetDestination ();

   131   Mac48Address from = header.GetSource ();

   132   

   133   NetDevice::PacketType packetType;

   134   if (to == m_address)

   135     {

   136       packetType = NetDevice::PACKET_HOST;

   137     }

   138   else if (to.IsBroadcast ())

   139     {

   140       packetType = NetDevice::PACKET_HOST;

   141     }

   142   else if (to.IsMulticast ())

   143     {

   144       packetType = NetDevice::PACKET_MULTICAST;

   145     }

   146   else 

   147     {

   148       packetType = NetDevice::PACKET_OTHERHOST;

   149     }

   150   m_rxTrace (copy, from, to);

   151   if (packetType != NetDevice::PACKET_OTHERHOST)

   152     {

   153       m_rxCallback (this, packet, protocol, from);

   154     }

   155   if (!m_promiscCallback.IsNull ())

   156     {

   157       m_promiscCallback (this, packet, protocol, from, to, packetType);

   158     }

   159 }

   160 

   161 void 

   162 TapNetDevice::SetAddress (Mac48Address address)

   163 {

   164   m_address = address;

   165 }

   166 

   167 void 

   168 TapNetDevice::SetName(const std::string name)

   169 {

   170   m_name = name;

   171 }

   172 std::string 

   173 TapNetDevice::GetName(void) const

   174 {

   175   return m_name;

   176 }

   177 void 

   178 TapNetDevice::SetIfIndex(const uint32_t index)

   179 {

   180   m_ifIndex = index;

   181 }

   182 uint32_t 

   183 TapNetDevice::GetIfIndex(void) const

   184 {

   185   return m_ifIndex;

   186 }

   187 Ptr<Channel> 

   188 TapNetDevice::GetChannel (void) const

   189 {

   190   return m_channel;

   191 }

   192 Address 

   193 TapNetDevice::GetAddress (void) const

   194 {

   195   return m_address;

   196 }

   197 bool 

   198 TapNetDevice::SetMtu (const uint16_t mtu)

   199 {

   200   m_mtu = mtu;

   201   return true;

   202 }

   203 uint16_t 

   204 TapNetDevice::GetMtu (void) const

   205 {

   206   return m_mtu;

   207 }

   208 bool 

   209 TapNetDevice::IsLinkUp (void) const

   210 {

   211   return true;

   212 }

   213 void 

   214 TapNetDevice::SetLinkChangeCallback (Callback<void> callback)

   215 {}

   216 bool 

   217 TapNetDevice::IsBroadcast (void) const

   218 {

   219   return true;

   220 }

   221 Address

   222 TapNetDevice::GetBroadcast (void) const

   223 {

   224   return Mac48Address ("ff:ff:ff:ff:ff:ff");

   225 }

   226 bool 

   227 TapNetDevice::IsMulticast (void) const

   228 {

   229   return true;

   230 }

   231 Address 

   232 TapNetDevice::GetMulticast (void) const

   233 {

   234   return Mac48Address::GetMulticastPrefix ();

   235 }

   236 Address 

   237 TapNetDevice::MakeMulticastAddress (Ipv4Address multicastGroup) const

   238 {

   239   return Mac48Address::GetMulticast (multicastGroup);

   240 }

   241 bool 

   242 TapNetDevice::IsPointToPoint (void) const

   243 {

   244   return false;

   245 }

   246 bool 

   247 TapNetDevice::Send(Ptr<Packet> packet, const Address& dest, uint16_t protocolNumber)

   248 {

   249   NS_LOG_FUNCTION (this << packet << dest << protocolNumber);

   250   return SendFrom (packet, m_address, dest, protocolNumber);

   251 }

   252 bool 

   253 TapNetDevice::SendFrom(Ptr<Packet> packet, const Address& source, const Address& dest, uint16_t protocolNumber)

   254 {

   255   NS_LOG_FUNCTION (this << packet << source << dest << protocolNumber);

   256   Mac48Address to = Mac48Address::ConvertFrom (dest);

   257   Mac48Address from = Mac48Address::ConvertFrom (source);

   258 

   259   EthernetHeader header = EthernetHeader (false);

   260   header.SetSource (from);

   261   header.SetDestination (to);

   262   header.SetLengthType (protocolNumber);

   263   packet->AddHeader (header);

   264 

   265   ssize_t written = write (m_tap, packet->PeekData (), packet->GetSize ());

   266   if (written == -1 || written != (ssize_t)packet->GetSize ())

   267     {

   268       m_dropTrace (packet, from, to);

   269       return false;

   270     }

   271 

   272   m_txTrace (packet, from, to);

   273   

   274   return true;

   275 }

   276 

   277 Ptr<Node> 

   278 TapNetDevice::GetNode (void) const

   279 {

   280   return m_node;

   281 }

   282 void 

   283 TapNetDevice::SetNode (Ptr<Node> node)

   284 {

   285   m_node = node;

   286 }

   287 bool 

   288 TapNetDevice::NeedsArp (void) const

   289 {

   290   return true;

   291 }

   292 void 

   293 TapNetDevice::SetReceiveCallback (NetDevice::ReceiveCallback cb)

   294 {

   295   m_rxCallback = cb;

   296 }

   297 

   298 void

   299 TapNetDevice::DoDispose (void)

   300 {

   301   NS_LOG_FUNCTION (this);

   302   close (m_tap);

   303   m_thread->Join ();

   304   m_thread = 0;

   305   m_node = 0;

   306   m_channel = 0;

   307   NetDevice::DoDispose ();

   308 }

   309 

   310 

   311 void

   312 TapNetDevice::SetPromiscReceiveCallback (PromiscReceiveCallback cb)

   313 {

   314   m_promiscCallback = cb;

   315 }

   316 

   317 bool

   318 TapNetDevice::SupportsSendFrom (void) const

   319 {

   320   return true;

   321 }

   322 

   323 } // namespace ns3