Port Scan Attack

[Amit Khandelwal]

Hi,
I am trying to extend the Simple port Scanner so that it displays the open ports found. For which I made following changes and launched the application. '
But it turned out that the method "handleIncomingPacket" is never getting executed?

1. Does that mean the server is not replying? ( I have profiled a server with Echo Server profile)
2. Or is there a fault in the logic?

import de.dailab.nessi.core.api.annotations.Description;
import de.dailab.nessi.core.api.annotations.IntegerField;
import de.dailab.nessi.core.api.annotations.StringField;
import de.dailab.nessi.core.api.events.Event;
import de.dailab.nessi.core.api.events.TickedEvent;
import de.dailab.nessi.ip.api.address.IPFactory;
import de.dailab.nessi.ip.api.address.IPv4Address;
import de.dailab.nessi.ip.api.layer.ILayerHandler;
import de.dailab.nessi.ip.api.layer.ITransportLayer;
import de.dailab.nessi.ip.api.protocols.Packet;
import de.dailab.nessi.ip.api.protocols.ip.IPv4Header;
import de.dailab.nessi.ip.api.protocols.udp.UDPHeader;
import de.dailab.nessi.ip.handler.IPApplication;
import java.util.Random;

public class Port_AK extends IPApplication
{

    public Port_AK()
    {
        startPort = 1;
        endPort = 1024;
        targetIp = "0.0.0.0";
        startTick = 100;
        System.out.print("Inside constructor ");

    }

    public void handleEvent(Event e)
    {
        System.out.print("Insie handleevent ");
        Random ran = new Random(123L);
        for(int i = startPort; i < endPort; i++)
        {
            System.out.print("Inside for loop ");
            byte payload[] = new byte[28];
            ran.nextBytes(payload);
            getLayerHandler().getTransportLayer().sendUDPPacket(7, i, destinationIP, payload);
        }
        System.out.print("Exiting handle event ");
        //super.handleEvent(e);
    }

    public boolean start()
    {
        System.out.print("Inside start ");
        destinationIP = IPFactory.createIPv4Address(targetIp);
        TickedEvent e = new TickedEvent(this, startTick);
        getLayerHandler().addEvent(e);
        System.out.print("Exiing start ");

        return super.start();
    }

    @Override
    public void handleIncomingPacket(Packet packet) {
        System.out.print("Inside handle incoming packets ");
    IPv4Header ipHeader = packet.findHeader(IPv4Header.class);
    UDPHeader udpHeader = packet.findHeader(UDPHeader.class);
    if (ipHeader == null || udpHeader == null) {
    return;
    }  
    System.out.print("The port replied back is ");
    System.out.println(udpHeader.getSourcePort());
    }

    @IntegerField("Start Port")
    @Description("Start Port number")
    private int startPort;
    @IntegerField("End Port")
    @Description("End")
    private int endPort;
    @StringField("IP Address")
    private String targetIp;
    private int startTick;
    private IPv4Address destinationIP;
}

[Karsten Bsufka]

What do you mean by launched the application? Did you add your implemented application to profile and placed in the profile on a node in the network before launching a new simulation?

Also from the Javadoc of handleIncomingPacket: "Called when a packet arrives. It is only used for normal applications which have registered a UDP port (see
ITransportLayer#registerUDPPort(int, IIPApplication)). This should preferably be done by overriding the start method."

I could not see that you registered any port.

[Amit Khandelwal]

Yes, by launching I mean : I created a elipse/maven prject with above source code. Then "mvn clean install". Then copied the .jar file into nessi backend and gui application folder. Then built a plug in project in Nessi2 GUI and placed this newly generatd appliction(profile) into a node. Then launched the simulation.

[Amit Khandelwal]

Thanks for the reply... I will try out your suggestions