Windows XTEA encryption problem

[Liuciferis]

Hello,

I am writing a Java server emulator for Tibia and I having some problems with XTEA encryption.
My encyption:

    public static byte[] encrypt(byte[] bytes, long[] key) throws IOException
    {
        ByteArrayOutputStream st = new ByteArrayOutputStream();
        st.write(bytes);

        long delta = 0x61C88647;

        // the message must be a multiple of 8
        int paddingBytes = bytes.length & 7;
        if (paddingBytes != 0) {
            int count = 8 - paddingBytes;
            for (int i = 0; i < count; i++)
                st.write(0x33);
        }
      
        bytes = st.toByteArray();

        int messageLength = bytes.length / 4;
        int readPos = 0;

        while (readPos < messageLength)
        {
            long v0 = bytes[readPos], v1 = bytes[readPos + 1];
            long sum = 0;

            for (int i = 32; --i >= 0;)
            {
                v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + key[(int) (sum & 3)]);
                sum -= delta;
                v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + key[(int) ((sum >> 11) & 3)]);
            }

            bytes[readPos++] = (byte) v0;
            bytes[readPos++] = (byte) v1;
        }
        return bytes;
    }

Encryption result:

Normal:
35 0 14 E 0 31 A 48 65 6C 6C 6F 20 77 6F 72 6C 64 21 64 1 0 5 0 41 75 72 65 61 9 0 31 32 37 2E 30 2E 30 2E 31 4 1C 0 1 0 6 0 57 64 65 6D 6F 6E FF FF

Encrypted:
AB A3 92 81 FC 31 F3 F3 AF 85 C3 D7 C3 24 6F 72 6C 64 21 64 1 0 5 0 41 75 72 65 61 9 0 31 32 37 2E 30 2E 30 2E 31 4 1C 0 1 0 6 0 57 64 65 6D 6F 6E FF FF 33

As you can see, it encrypts only ~14 bytes at the beginning and that's all.

I have no idea why it works like that. Maybe someone could answer me?

 

[Liuciferis]

EDIT: asd

 

[esfomeado]

Why not use someone else implementation like:
http://source.db4o.com/db4o/trunk/db4oME/com/db4o/io/crypt/XTEA.java

 

[Liuciferis]

I'll take a look. Thank you.

 

[Liuciferis]

Hm. What could be wrong if xtea encrypted bytes are different than original packet?

XTEA:

package com.network.encryption;

import java.io.ByteArrayOutputStream;
import java.io.IOException;

public class XTEA
{
    private static final int DELTA = 0x9E3779B9; //0x61C88647;//0x9E3779B9;
    private static final int iteration = 0xC6EF3720;

    private long[] _key;

    public XTEA(long[] key) throws IllegalArgumentException
    {
        if (key.length != 4)
            throw new IllegalArgumentException();

        _key = key;
    }

    private void byte2int(byte[] bytes, int offset, int[] res)
    {
        res[0] = (int) ((((int) bytes[offset] & 0xff) << 24)
                | (((int) bytes[offset + 1] & 0xff) << 16)
                | (((int) bytes[offset + 2] & 0xff) << 8) | ((int) bytes[offset + 3] & 0xff));
        res[1] = (int) ((((int) bytes[offset + 4] & 0xff) << 24)
                | (((int) bytes[offset + 5] & 0xff) << 16)
                | (((int) bytes[offset + 6] & 0xff) << 8) | ((int) bytes[offset + 7] & 0xff));
    }

    private void int2byte(int[] i, int offset, byte[] res)
    {
        res[offset] = (byte) ((i[0] & 0xff000000) >>> 24);
        res[offset + 1] = (byte) ((i[0] & 0x00ff0000) >>> 16);
        res[offset + 2] = (byte) ((i[0] & 0x0000ff00) >>> 8);
        res[offset + 3] = (byte) (i[0] & 0x000000ff);
        res[offset + 4] = (byte) ((i[1] & 0xff000000) >>> 24);
        res[offset + 5] = (byte) ((i[1] & 0x00ff0000) >>> 16);
        res[offset + 6] = (byte) ((i[1] & 0x0000ff00) >>> 8);
        res[offset + 7] = (byte) (i[1] & 0x000000ff);
    }

    private void encipher(int[] block)
    {
        int n = 32;
        int delta_sum = 0;
        while (n-- > 0)
        {
            block[0] += ((block[1] << 4 ^ block[1] >> 5) + block[1])
                    ^ (delta_sum + _key[delta_sum & 3]);
            delta_sum += DELTA;
            block[1] += ((block[0] << 4 ^ block[0] >> 5) + block[0])
                    ^ (delta_sum + _key[delta_sum >> 11 & 3]);
        }
    }

    private void decipher(int[] e_block)
    {
        int delta_sum = iteration;
        int n = 32;
        while (n-- > 0)
        {
            e_block[1] -= ((e_block[0] << 4 ^ e_block[0] >> 5) + e_block[0])
                    ^ (delta_sum + _key[delta_sum >> 11 & 3]);
            delta_sum -= DELTA;
            e_block[0] -= ((e_block[1] << 4 ^ e_block[1] >> 5) + e_block[1])
                    ^ (delta_sum + _key[delta_sum & 3]);
        }
    }

    public byte[] encrypt(byte[] buffer) throws IOException
    {
        ByteArrayOutputStream st = new ByteArrayOutputStream();
        st.write(buffer);
       
        int paddingBytes = st.size() & 7;
        if (paddingBytes != 0)
        {
            for (int i = 0; i < 8 - paddingBytes; i++)
                st.write(0x33);
        }
       
        byte[] bb = st.toByteArray();

        int[] asInt = new int[2];
        for (int i = 0; i < bb.length; i += 8)
        {
            byte2int(bb, i, asInt);
            encipher(asInt);
            int2byte(asInt, i, bb);
        }
        return bb;
    }

    public byte[] decrypt(byte[] buffer)
    {
        int[] asInt = new int[2];
        for (int i = 0; i < buffer.length; i += 8)
        {
            byte2int(buffer, i, asInt);
            decipher(asInt);
            int2byte(asInt, i, buffer);
        }
        return buffer;
    }
}