KeyGenerator.java

import l2e.commons.util.Base64;
import l2e.commons.util.Functions;

import java.io.UnsupportedEncodingException;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class KeyGenerator
{
    
    private static String _key = "";
    
    public static void main(String[] args) throws NoSuchAlgorithmException, UnsupportedEncodingException
    {
        // Check server.ini, find field UserName and set your desired UserName in server.ini (dont forget to update it here)
        applyKey("REPLACE_ME_WITH_NEW_USER_NAME_FROM_SERVER_INI_IN_CONFIGS", "127.0.0.1");
        System.out.println("The valid key for the given User Name and External Host is: " + _key);
    }
    
    private static String getBufferKey(String s)
    {
        try
        {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(s.getBytes());
            StringBuilder hexString = new StringBuilder();
            byte[] byteData = md.digest();
            for (byte aByteData : byteData)
            {
                String hex = Integer.toHexString(0xFF & aByteData);
                if (hex.length() == 1)
                    hexString.append('0');
                hexString.append(hex);
            }
            return hexString.toString();
        }
        catch (Exception exception)
        {
            return null;
        }
    }
    
    private static void getGenerateByte(String s, String s1, String s2)
    {
        try
        {
            String finalKey = s2 + s + s2 + s1;
            MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] raw = finalKey.getBytes(StandardCharsets.UTF_8);
            byte[] hash = md.digest(raw);
            _key = Base64.encodeBytes(hash);
            Functions.setBuffKey(_key);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }
    
    public static void applyKey(String configUserName, String EXTERNAL_HOSTNAME)
    {
        try
        {
            String toEncrypt = System.getenv("COMPUTERNAME") + System.getProperty("user.name") + System.getenv("PROCESSOR_IDENTIFIER") + System.getenv("PROCESSOR_LEVEL");
            String pcKey = getBufferKey(toEncrypt);
            getGenerateByte(pcKey, getBufferKey(configUserName), getBufferKey(EXTERNAL_HOSTNAME));
        }
        catch (Exception exception)
        {
            exception.printStackTrace();
        }
    }
}