(internet): IPv6 Duplicate Address Detection (DAD) must use Solicited-Node multicast address

src/internet/model/icmpv6-l4-protocol.cc

@@ -572,7 +572,10 @@ void Icmpv6L4Protocol::HandleNS (Ptr<Packet> packet, Ipv6Address const &src, Ipv
     }
 
   hardwareAddress = interface->GetDevice ()->GetAddress ();
-  NdiscCache::Ipv6PayloadHeaderPair p = ForgeNA (target.IsLinkLocal () ? interface->GetLinkLocalAddress ().GetAddress () : ifaddr.GetAddress (), src.IsAny () ? Ipv6Address::GetAllNodesMulticast () : src, &hardwareAddress, flags );
+  NdiscCache::Ipv6PayloadHeaderPair p = ForgeNA (target.IsLinkLocal () ? interface->GetLinkLocalAddress ().GetAddress () : ifaddr.GetAddress (),
+                                                 src.IsAny () ? dst : src, // DAD replies must go to the multicast group it was sent to.
+                                                 &hardwareAddress,
+                                                 flags );
   interface->Send (p.first, p.second, src.IsAny () ? Ipv6Address::GetAllNodesMulticast () : src);
 
   /* not a NS for us discard it */
@@ -1253,12 +1256,6 @@ NdiscCache::Ipv6PayloadHeaderPair Icmpv6L4Protocol::ForgeNS (Ipv6Address src, Ip
   Icmpv6NS ns (target);
   Icmpv6OptionLinkLayerAddress llOption (1, hardwareAddress);  /* we give our mac address in response */
 
-  /* if the source is unspec, multicast the NA to all-nodes multicast */
-  if (src == Ipv6Address::GetAny ())
-    {
-      dst = Ipv6Address::GetAllNodesMulticast ();
-    }
-
   NS_LOG_LOGIC ("Send NS ( from " << src << " to " << dst << " target " << target << ")");
 
   p->AddHeader (llOption);

src/internet/test/ipv6-address-duplication-test.cc

@@ -0,0 +1,134 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2020 Universita' di Firenze
+ * 
+ * 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: Tommaso Pecorella <tommaso.pecorella@unifi.it>
+ */
+
+#include "ns3/test.h"
+#include "ns3/socket-factory.h"
+#include "ns3/udp-socket-factory.h"
+#include "ns3/simulator.h"
+#include "ns3/simple-channel.h"
+#include "ns3/simple-net-device.h"
+#include "ns3/simple-net-device-helper.h"
+#include "ns3/socket.h"
+#include "ns3/boolean.h"
+
+#include "ns3/log.h"
+#include "ns3/node.h"
+#include "ns3/inet6-socket-address.h"
+
+#include "ns3/ipv6-l3-protocol.h"
+#include "ns3/icmpv6-l4-protocol.h"
+#include "ns3/udp-l4-protocol.h"
+#include "ns3/ipv6-static-routing.h"
+#include "ns3/internet-stack-helper.h"
+#include "ns3/ipv6-address-helper.h"
+#include "ns3/ipv6-routing-helper.h"
+
+#include <string>
+#include <limits>
+
+using namespace ns3;
+
+/**
+ * \ingroup internet-test
+ * \ingroup tests
+ *
+ * \brief IPv6 Duplicate Address Detection Test
+ */
+class Ipv6DadTest : public TestCase
+{
+public:
+  virtual void DoRun (void);
+  Ipv6DadTest ();
+};
+
+Ipv6DadTest::Ipv6DadTest ()
+  : TestCase ("IPv6 Duplicate Address Detection")
+{
+}
+
+void
+Ipv6DadTest::DoRun (void)
+{
+  // Create topology
+
+  Ptr<Node> Node1 = CreateObject<Node> ();
+  Ptr<Node> Node2 = CreateObject<Node> ();
+
+  NodeContainer nodes (Node1, Node2);
+
+  SimpleNetDeviceHelper helperChannel;
+  helperChannel.SetNetDevicePointToPointMode (true);
+  NetDeviceContainer net = helperChannel.Install (nodes);
+
+  InternetStackHelper internetv6;
+  internetv6.Install (nodes);
+
+  Ipv6AddressHelper ipv6helper;
+  Ipv6InterfaceContainer iic = ipv6helper.AssignWithoutAddress (net);
+
+  Ptr<NetDevice> device;
+  Ipv6InterfaceAddress ipv6Addr;
+
+  Ptr<Ipv6> ipv6node1;
+  int32_t ifIndexNode1;
+  ipv6node1 = Node1->GetObject<Ipv6> ();
+  device = net.Get (0);
+  ifIndexNode1 = ipv6node1->GetInterfaceForDevice (device);
+  ipv6Addr = Ipv6InterfaceAddress (Ipv6Address ("2001:1::1"), Ipv6Prefix (64));
+  ipv6node1->AddAddress (ifIndexNode1, ipv6Addr);
+
+  Ptr<Ipv6> ipv6node2;
+  int32_t ifIndexNode2;
+  ipv6node2 = Node2->GetObject<Ipv6> ();
+  device = net.Get (1);
+  ifIndexNode2 = ipv6node2->GetInterfaceForDevice (device);
+  ipv6Addr = Ipv6InterfaceAddress (Ipv6Address ("2001:1::1"), Ipv6Prefix (64));
+  ipv6node2->AddAddress (ifIndexNode2, ipv6Addr);
+
+  Simulator::Run ();
+
+  Ipv6InterfaceAddress addr1 = ipv6node1->GetAddress (ifIndexNode1, 1);
+  Ipv6InterfaceAddress::State_e node1AddrState = addr1.GetState();
+  NS_TEST_ASSERT_MSG_EQ (node1AddrState, Ipv6InterfaceAddress::INVALID, "Failed to detect duplicate address on node 1");
+
+  Ipv6InterfaceAddress addr2 = ipv6node2->GetAddress (ifIndexNode2, 1);
+  Ipv6InterfaceAddress::State_e node2AddrState = addr2.GetState();
+  NS_TEST_ASSERT_MSG_EQ (node2AddrState, Ipv6InterfaceAddress::INVALID, "Failed to detect duplicate address on node 2");
+
+  Simulator::Destroy ();
+}
+
+
+/**
+ * \ingroup internet-test
+ * \ingroup tests
+ *
+ * \brief IPv6 Duplicate Address Detection TestSuite
+ */
+class Ipv6DadTestSuite : public TestSuite
+{
+public:
+  Ipv6DadTestSuite () : TestSuite ("ipv6-duplicate-address-detection", UNIT)
+  {
+    AddTestCase (new Ipv6DadTest, TestCase::QUICK);
+  }
+};
+
+static Ipv6DadTestSuite g_ipv6dadTestSuite; //!< Static variable for test initialization

src/internet/wscript

@@ -251,6 +251,7 @@ def build(bld):
         'test/ipv6-packet-info-tag-test-suite.cc',
         'test/ipv6-test.cc',
         'test/ipv6-raw-test.cc',
+        'test/ipv6-address-duplication-test.cc',
         'test/tcp-test.cc',
         'test/tcp-timestamp-test.cc',
         'test/tcp-sack-permitted-test.cc',