Windows Security Tutorials - Herong's Tutorial Examples - v3.01, by Dr. Herong Yang
MulticastListener.java - A Simple Multicast Listener Program
This section provides a tutorial example on how to write a simple Java test program to join any given multicast group and listen to incoming messages.
In order to find out more information about the MS08-001 vulnerability and its relation with multicast communication, I wrote a very simple test program, MulticastListener.java, to join any given multicast group and listen for incoming messages:
/**
* MulticastListener.java
* Copyright (c) 2008 by Dr. Herong Yang, http://www.herongyang.com/
*/
import java.io.*;
import java.net.*;
public class MulticastListener {
public static void main(String[] args) {
if (args.length < 2) {
System.out.println
("Usage: java MulticastListener 224.0.0.1 Herong");
return;
}
String ip = args[0];
String name = args[1];;
int port = 6789;
try {
InetAddress group = InetAddress.getByName(ip);
MulticastSocket s = new MulticastSocket(port);
s.joinGroup(group);
String msg = "Greeting from "+name;
System.out.println("Sending out: "+msg);
DatagramPacket data = new DatagramPacket(
msg.getBytes(), msg.length(), group, port);
s.send(data);
byte[] buffer = new byte[10*1024];
data = new DatagramPacket(buffer, buffer.length);
while (true) {
s.receive(data);
System.out.println("Received: "+
(new String(buffer, 0, data.getLength())));
}
} catch (IOException e) {
System.out.println(e.toString());
}
}
}
I compiled and ran the program on my Windows XP system. Here is the output:
C:\herong>javac MulticastListener.java C:\herong>java MulticastListener 224.0.0.1 Herong Sending out: Greeting from Herong Received: Greeting from Herong Received: Greeting from Herong
2 interesting notes:
In the next test, I used multicast IP address that is not reserved for any special purposes, 224.0.0.3 I compiled and ran the program on my Windows XP system. Here is the output:
C:\herong>java MulticastListener 224.0.0.3 Herong Sending out: Greeting from Herong Received: Greeting from Herong
This test proves that my system with 2 IP interfaces, Wireless and Ethernet, connected to the same physical network, provided by my wireless hub, will receive 2 copies of messages multi casted to the All Hosts Multicast Group, 224.0.0.1.
I started another command window and run "java MulticastListener 224.0.0.3 Guest". On my first command window, I got the greeting message from Guest correctly:
C:\herong>java MulticastListener 224.0.0.3 Herong Sending out: Greeting from Herong Received: Greeting from Herong Received: Greeting from Guest
Table of Contents
About This Windows Security Book
Windows 8: System Security Review
Windows 8: System Security Protection
Windows 8 Defender for Real-Time Protection
Windows 7: System Security Review
Windows 7: System Security Protection
Windows 7 Forefront Client Security
Norton Power Eraser - Anti-Virus Scan Tool
McAfee Virus and Malware Protection Tools
Spybot - Spyware Blocker, Detection and Removal
Keeping IE (Internet Explorer) Secure
Malware (Adware, Spyware, Trojan, Worm, and Virus)
HijackThis - Browser Hijacker Diagnosis Tool
IE Add-on Program Listing and Removal
"Conduit Search" - Malware Detection and Removal
"Tube Dimmer", "Scorpion Saver" or "Adpeak" Malware
Malware Manual Removal Experience
Vundo (VirtuMonde/VirtuMundo) - vtsts.dll Removal
Trojan and Malware "Puper" Description and Removal
VSToolbar (VSAdd-in.dll) - Description and Removal
PWS (Password Stealer) Trojan Infection Removal
►MS08-001 Vulnerability on Windows Systems
MS08-001 - Vulnerability in TCP/IP
IP Multicast and IP Address Range
"netsh" Commands for Interface IP
224.0.0.1 - The All Hosts Multicast Group
►MulticastListener.java - A Simple Multicast Listener Program
All Hosts Multicast Group, 224.0.0.1, on Vista Systems