olsr: (fixes #2760) do not use unicast-bound sockets to receive broadcasts

RELEASE_NOTES

@@ -107,6 +107,7 @@ Bugs fixed
 - Bug 2744 - 802.11n/ac with RTS/CTS is crashing for a large number of nodes
 - Bug 2758 - IPv4 sockets bound to unicast receive also subnet-directed broadcasts
 - Bug 2759 - Packets sent to broadcast address are converted to subnet-directed broadcast
+- Bug 2760 - OLSR uses unicast-bound sockets to receive broadcasts
 
 Known issues
 ------------

src/olsr/model/olsr-routing-protocol.cc

@@ -47,6 +47,7 @@
 #include "ns3/enum.h"
 #include "ns3/trace-source-accessor.h"
 #include "ns3/ipv4-header.h"
+#include "ns3/ipv4-packet-info-tag.h"
 
 /********** Useful macros **********/
 
@@ -240,12 +241,17 @@ void RoutingProtocol::DoDispose ()
   m_hnaRoutingTable = 0;
   m_routingTableAssociation = 0;
 
-  for (std::map< Ptr<Socket>, Ipv4InterfaceAddress >::iterator iter = m_socketAddresses.begin ();
-       iter != m_socketAddresses.end (); iter++)
+  if (m_recvSocket)
+    {
+      m_recvSocket->Close ();
+    }
+
+  for (std::map< Ptr<Socket>, Ipv4InterfaceAddress >::iterator iter = m_sendSockets.begin ();
+       iter != m_sendSockets.end (); iter++)
     {
       iter->first->Close ();
     }
-  m_socketAddresses.clear ();
+  m_sendSockets.clear ();
 
   Ipv4RoutingProtocol::DoDispose ();
 }
@@ -340,7 +346,23 @@ void RoutingProtocol::DoInitialize ()
           continue;
         }
 
-      // Create a socket to listen only on this interface
+      // Create a socket to listen on all the interfaces
+      if (m_recvSocket == 0)
+        {
+          m_recvSocket = Socket::CreateSocket (GetObject<Node> (),
+                                               UdpSocketFactory::GetTypeId ());
+          m_recvSocket->SetAllowBroadcast (true);
+          InetSocketAddress inetAddr (Ipv4Address::GetAny (), OLSR_PORT_NUMBER);
+          m_recvSocket->SetRecvCallback (MakeCallback (&RoutingProtocol::RecvOlsr,  this));
+          if (m_recvSocket->Bind (inetAddr))
+            {
+              NS_FATAL_ERROR ("Failed to bind() OLSR socket");
+            }
+          m_recvSocket->SetRecvPktInfo (true);
+          m_recvSocket->ShutdownSend ();
+        }
+
+      // Create a socket to send packets from this specific interfaces
       Ptr<Socket> socket = Socket::CreateSocket (GetObject<Node> (),
                                                  UdpSocketFactory::GetTypeId ());
       socket->SetAllowBroadcast (true);
@@ -351,7 +373,8 @@ void RoutingProtocol::DoInitialize ()
           NS_FATAL_ERROR ("Failed to bind() OLSR socket");
         }
       socket->BindToNetDevice (m_ipv4->GetNetDevice (i));
-      m_socketAddresses[socket] = m_ipv4->GetAddress (i, 0);
+      socket->SetRecvPktInfo (true);
+      m_sendSockets[socket] = m_ipv4->GetAddress (i, 0);
 
       canRunOlsr = true;
     }
@@ -386,9 +409,33 @@ RoutingProtocol::RecvOlsr (Ptr<Socket> socket)
   Address sourceAddress;
   receivedPacket = socket->RecvFrom (sourceAddress);
 
+  Ipv4PacketInfoTag interfaceInfo;
+  if (!receivedPacket->RemovePacketTag (interfaceInfo))
+    {
+      NS_ABORT_MSG ("No incoming interface on OLSR message, aborting.");
+    }
+  uint32_t incomingIf = interfaceInfo.GetRecvIf ();
+  Ptr<Node> node = this->GetObject<Node> ();
+  Ptr<NetDevice> dev = node->GetDevice (incomingIf);
+  uint32_t recvInterfaceIndex = m_ipv4->GetInterfaceForDevice (dev);
+
+  if (m_interfaceExclusions.find (recvInterfaceIndex) != m_interfaceExclusions.end ())
+    {
+      return;
+    }
+
+
   InetSocketAddress inetSourceAddr = InetSocketAddress::ConvertFrom (sourceAddress);
   Ipv4Address senderIfaceAddr = inetSourceAddr.GetIpv4 ();
-  Ipv4Address receiverIfaceAddr = m_socketAddresses[socket].GetLocal ();
+
+  int32_t interfaceForAddress = m_ipv4->GetInterfaceForAddress (senderIfaceAddr);
+  if (interfaceForAddress != -1)
+    {
+      NS_LOG_LOGIC ("Ignoring a packet sent by myself.");
+      return;
+    }
+
+  Ipv4Address receiverIfaceAddr = m_ipv4->GetAddress (recvInterfaceIndex, 0).GetLocal ();
   NS_ASSERT (receiverIfaceAddr != Ipv4Address ());
   NS_LOG_DEBUG ("OLSR node " << m_mainAddress << " received a OLSR packet from "
                              << senderIfaceAddr << " to " << receiverIfaceAddr);
@@ -1588,10 +1635,11 @@ RoutingProtocol::SendPacket (Ptr<Packet> packet,
 
   // Send it
   for (std::map<Ptr<Socket>, Ipv4InterfaceAddress>::const_iterator i =
-         m_socketAddresses.begin (); i != m_socketAddresses.end (); i++)
+         m_sendSockets.begin (); i != m_sendSockets.end (); i++)
     {
+      Ptr<Packet> pkt = packet->Copy ();
       Ipv4Address bcast = i->second.GetLocal ().GetSubnetDirectedBroadcast (i->second.GetMask ());
-      i->first->SendTo (packet, 0, InetSocketAddress (bcast, OLSR_PORT_NUMBER));
+      i->first->SendTo (pkt, 0, InetSocketAddress (bcast, OLSR_PORT_NUMBER));
     }
 }
 
@@ -3082,8 +3130,8 @@ RoutingProtocol::AssignStreams (int64_t stream)
 bool
 RoutingProtocol::IsMyOwnAddress (const Ipv4Address & a) const
 {
-  for (std::map<Ptr<Socket>, Ipv4InterfaceAddress>::const_iterator j =
-         m_socketAddresses.begin (); j != m_socketAddresses.end (); ++j)
+  std::map<Ptr<Socket>, Ipv4InterfaceAddress>::const_iterator j;
+  for (j = m_sendSockets.begin (); j != m_sendSockets.end (); ++j)
     {
       Ipv4InterfaceAddress iface = j->second;
       if (a == iface.GetLocal ())

src/olsr/model/olsr-routing-protocol.h

@@ -764,7 +764,9 @@ private:
   // One socket per interface, each bound to that interface's address
   // (reason: for OLSR Link Sensing we need to know on which interface
   // HELLO messages arrive)
-  std::map< Ptr<Socket>, Ipv4InterfaceAddress > m_socketAddresses; //!< Container of sockets and the interfaces they are opened onto.
+  std::map< Ptr<Socket>, Ipv4InterfaceAddress > m_sendSockets; //!< Container of sockets and the interfaces they are opened onto.
+  Ptr<Socket> m_recvSocket; //!< Receiving socket.
+
 
   /// Rx packet trace.
   TracedCallback <const PacketHeader &, const MessageList &> m_rxPacketTrace;