To implement passive attacks in ns3, we have to eavesdrop on the network traffic without actively injecting any packets or disrupting the network. You can implement a passive attack in ns3 by setting up a node which captures and logs packets being transmitted through the network.
Here is a quick and complete guide on implementing passive attacks in ns3.
Steps for implementation
- Set up your ns3 :
- Make sure that ns3 is installed in the computer. If not, install it.
- Create a new ns3 script :
- In the scratch directory of ns3, create a new script.
- Include necessary libraries :
- In your script, include the necessary libraries.
- Define network topology :
- For your network topology, create multiple nodes and one passive attacker node.
- Implement the packet sniffing logic :
- On the attacker node, use packet sniffer to capture and log packtes.
- Enable packet capturing :
- Enable pcap tracing to capture packets for analysis with Wireshark.
- Run the Simulation :
- Define the simulation parameters and run it.
Example for implementing Passive attack in ns3
Here is the example for the implementation of Passive attack :
#include “ns3/core-module.h”
#include “ns3/network-module.h”
#include “ns3/internet-module.h”
#include “ns3/point-to-point-module.h”
#include “ns3/applications-module.h”
#include “ns3/packet-sink.h”
#include “ns3/pcap-file.h”
using namespace ns3;
NS_LOG_COMPONENT_DEFINE (“PassiveAttack”);
void PacketCapture (Ptr<const Packet> packet)
{
// Log packet information (for example, packet size)
NS_LOG_INFO (“Captured packet of size: ” << packet->GetSize ());
}
int main (int argc, char *argv[])
{
// Set up logging
LogComponentEnable (“PassiveAttack”, LOG_LEVEL_INFO);
// Create nodes
NodeContainer nodes;
nodes.Create (4); // Three legitimate nodes and one passive attacker node
// Create point-to-point links
PointToPointHelper pointToPoint;
pointToPoint.SetDeviceAttribute (“DataRate”, StringValue (“5Mbps”));
pointToPoint.SetChannelAttribute (“Delay”, StringValue (“2ms”));
NetDeviceContainer devices;
for (uint32_t i = 0; i < nodes.GetN () – 1; ++i)
{
devices.Add (pointToPoint.Install (nodes.Get (i), nodes.Get (i + 1)));
}
// Install the internet stack
InternetStackHelper stack;
stack.Install (nodes);
// Assign IP addresses
Ipv4AddressHelper address;
address.SetBase (“10.1.1.0”, “255.255.255.0”);
Ipv4InterfaceContainer interfaces = address.Assign (devices);
// Install applications on legitimate nodes
uint16_t port = 9; // Discard port (RFC 863)
// Server application
UdpEchoServerHelper echoServer (port);
ApplicationContainer serverApps = echoServer.Install (nodes.Get (1));
serverApps.Start (Seconds (1.0));
serverApps.Stop (Seconds (10.0));
// Client application
UdpEchoClientHelper echoClient (interfaces.GetAddress (1), port);
echoClient.SetAttribute (“MaxPackets”, UintegerValue (100));
echoClient.SetAttribute (“Interval”, TimeValue (Seconds (0.1)));
echoClient.SetAttribute (“PacketSize”, UintegerValue (1024));
ApplicationContainer clientApps = echoClient.Install (nodes.Get (0));
clientApps.Start (Seconds (2.0));
clientApps.Stop (Seconds (10.0));
// Enable packet capture
pointToPoint.EnablePcapAll (“passive_attack”);
// Set up packet capture on the passive attacker node
Ptr<NetDevice> attackerDevice = devices.Get (devices.GetN () – 1);
attackerDevice->TraceConnectWithoutContext (“PhyRxDrop”, MakeCallback (&PacketCapture));
// Run simulation
Simulator::Run ();
Simulator::Destroy ();
return 0;
}
Explanation
- Nodes and links :
Four nodes are created : three for legitimate communication and one for passive attacker. Point-to-point links between nodes are configured.
- Applications :
On one of the legitimate node, a UDP echo server is installed. and On another legitimate node, a UDP echo server is installed to generate traffic.
- Passive attack logic :
To log packet information, PacketCapture function is implemented. To capture packets, connected the packet capture function to the PhyRxDrop trace source of the attacker’s network device.
- Packet Capture :
To capture the traffic for analysis with Wireshark, pcap tracing on all nodes is enabled.
- Running the Simulation :
The simulation runs with attacker node passively capturing packets, and the traffic is captured in pcap files.