Thread: Anti SYI protection for Project Czar

I did not make the SYI protecter it was made by KEVIN, this tutorial is for Czar only, because that is the only server that has a strange server.java.

Description: Stopping an Syi crasher from attacking your server.

Difficulty: 2

Assumed Knowledge: Copy & Paste

Tested Server: Project Czar

Files/Classes Modified: Server.java, client.java

Procedure
Step 1: Make a new file called BanManager.java and put this inside:

Code:

import java.util.ArrayList;

public class BanManager 
{
 public final static void Initialize() // Ban Manager handler by Kevin
  {
   AddName("SYIpkpker");
   AddName("SilabSoft");
   AddName("runescape");
   AddName("thorak");
   AddName("CRASH");

AddAddress("e83-245-158-89.elisa-laajakaista.fi"); 
  }

  public final static void AddName(String Name)
  {
    Names.add(Name.toLowerCase());
  }

  public final static boolean BannedName(String _Name)
  {
   _Name = _Name.toLowerCase();

   for(String Name : Names)
    if(_Name.contains(Name))
      return true;

   for(Character c : _Name.toCharArray()) // <3 Silabsoft
    if(!Character.isLetterOrDigit(c))
     if(!Character.isSpaceChar(c))
      return true;

   return false;
  }

  public final static void AddAddress(String Address)
  {
    Addresses.add(Address.toLowerCase());
  }

  public final static boolean BannedAddress(String _Address)
  {
   _Address = _Address.toLowerCase();

   for(String Address : Addresses)
    if(Address.equals(_Address))
      return true;

   return false;
  }

  public static ArrayList<String> Names = new ArrayList<String>();
  public static ArrayList<String> Addresses = new ArrayList<String>();
}

Step 2: Open up client.java and search:

Code:

			if(playerName == null || playerName.length() == 0) 
                        disconnected = true;

Under that add:

Code:

			if(BanManager.BannedName(playerName)) //by kevin
       			{
        		BanManager.AddAddress(connectedFrom);
        		disconnected = true;
        		return;
       			}

Step 3: Now open up server.java ( backup your server.java ):

Add this to server.java:

Code:

public String connectingHost;

then Find,

Code:

public void run() {

Replace ALL the code below that with:

Code:

	public void run() {
		// setup the listener
		try {
			shutdownClientHandler = false;
			clientListener = new java.net.ServerSocket(serverlistenerPort, 1, null);
			misc.println("- YOUR SERVER NAME -");
			misc.println("NOW ONLINE!");
			while(true) {
				java.net.Socket s = acceptSocketSafe(clientListener);
				s.setTcpNoDelay(true);
                                connectingHost = s.getInetAddress().getHostName(); 
					if (server.playerHandler.checkBannedIps() == true) {
					misc.println(connectingHost+" is ip banned");
					s.close();
					} else {
				if(/*connectingHost.startsWith("localhost") || connectingHost.equals("127.0.0.1")*/true) {
  			        
                             	if(clientListener != null)
				{
				 if(!BanManager.BannedAddress(connectingHost)) 
				 {
				  misc.println("ClientHandler: Accepted from "+connectingHost+":"+s.getPort()); // by kevin
					 playerHandler.newPlayerClient(s, connectingHost);
				 }
				 else
				 {
					misc.println("ClientHandler: Rejected from "+connectingHost+":"+s.getPort()); // by kevin
				   s.close(); 
				 }
				}
			}
}
}
		} catch(java.io.IOException ioe) {
			if(!shutdownClientHandler) {
				misc.println("Error: Unable to startup listener on "+serverlistenerPort+" - port already in use?");
			} else {
				misc.println("ClientHandler was shut down.");
			}
		}
	}
	                public void killServer() {
		        try {
			shutdownClientHandler = true;
			if(clientListener != null) clientListener.close();
			clientListener = null;
		        } catch(java.lang.Exception __ex) {
			__ex.printStackTrace();
		        }
	                }
	public static int EnergyRegian = 0;

	public static int MaxConnections = 100000;
	public static String[] Connections = new String[MaxConnections];
	public static int[] ConnectionCount = new int[MaxConnections];
	public static boolean ShutDown = false;
	public static int ShutDownCounter = 0;


        }

Step 4: Open up playerhandler.java, and search:

Code:

		// anything can be done here like unlinking this player structure from any of the other existing structures
		plr.destruct();
	}

Directly under that add:

Code:

    public boolean checkBannedIps() {
	String bannedIp = null;
	try {
	    BufferedReader br = new BufferedReader(new FileReader("./data/bannedips.txt"));
	    while((bannedIp = br.readLine()) != null) {
		if(server.clientHandler.connectingHost.startsWith(bannedIp)) {
		    return true;
		}
	    }
	} catch(IOException e) {
	    System.err.println("Error reading the banned IPs list");
	}
	return false;
    }

Credits: Musicmad (for making it work with czar) Kevin for Anti Syi

THIS ALSO HAS WORKING IPBAN IN IT. MAKE SURE YOU HAVE A FILE CALLED: bannedips.txt in your data folder.

Thanks

Post all errors below.