/*
* This program is free software: you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later
* version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.netcon.crypt;
import java.io.IOException;
import java.util.logging.Logger;
public class NewCrypt
{
protected static Logger _log = Logger.getLogger(NewCrypt.class.getName());
BlowfishEngine _crypt;
BlowfishEngine _decrypt;
public NewCrypt(final byte[] blowfishKey)
{
_crypt = new BlowfishEngine();
_crypt.init(true, blowfishKey);
_decrypt = new BlowfishEngine();
_decrypt.init(false, blowfishKey);
}
public NewCrypt(final String key)
{
this(key.getBytes());
}
public static final boolean verifyChecksum(byte[] raw)
{
return NewCrypt.verifyChecksum(raw, 0, raw.length);
}
public static final boolean verifyChecksum(byte[] raw, final int offset, final int size)
{
// check if size is multiple of 4 and if there is more then only the checksum
if (((size & 3) != 0) || (size <= 4))
{
return false;
}
long chksum = 0;
int count = size - 4;
long check = -1;
int i;
for (i = offset; i < count; i += 4)
{
check = raw[i] & 0xff;
check |= (raw[i + 1] << 8) & 0xff00;
check |= (raw[i + 2] << 0x10) & 0xff0000;
check |= (raw[i + 3] << 0x18) & 0xff000000;
chksum ^= check;
}
check = raw[i] & 0xff;
check |= (raw[i + 1] << 8) & 0xff00;
check |= (raw[i + 2] << 0x10) & 0xff0000;
check |= (raw[i + 3] << 0x18) & 0xff000000;
return check == chksum;
}
public static final void appendChecksum(byte[] raw)
{
NewCrypt.appendChecksum(raw, 0, raw.length);
}
public static final void appendChecksum(byte[] raw, final int offset, final int size)
{
long chksum = 0;
int count = size - 4;
long ecx;
int i;
for (i = offset; i < count; i += 4)
{
ecx = raw[i] & 0xff;
ecx |= (raw[i + 1] << 8) & 0xff00;
ecx |= (raw[i + 2] << 0x10) & 0xff0000;
ecx |= (raw[i + 3] << 0x18) & 0xff000000;
chksum ^= ecx;
}
ecx = raw[i] & 0xff;
ecx |= (raw[i + 1] << 8) & 0xff00;
ecx |= (raw[i + 2] << 0x10) & 0xff0000;
ecx |= (raw[i + 3] << 0x18) & 0xff000000;
raw[i] = (byte) (chksum & 0xff);
raw[i + 1] = (byte) ((chksum >> 0x08) & 0xff);
raw[i + 2] = (byte) ((chksum >> 0x10) & 0xff);
raw[i + 3] = (byte) ((chksum >> 0x18) & 0xff);
}
/**
* Packet is first XOR encoded with <code>key</code> Then, the last 4 bytes are overwritten with the the XOR "key". Thus this assume that there is enough room for the key to fit without overwriting data.
* @param raw The raw bytes to be encrypted
* @param key The 4 bytes (int) XOR key
*/
public static final void encXORPass(byte[] raw, int key)
{
NewCrypt.encXORPass(raw, 0, raw.length, key);
}
/**
* Packet is first XOR encoded with <code>key</code> Then, the last 4 bytes are overwritten with the the XOR "key". Thus this assume that there is enough room for the key to fit without overwriting data.
* @param raw The raw bytes to be encrypted
* @param offset The begining of the data to be encrypted
* @param size Length of the data to be encrypted
* @param key The 4 bytes (int) XOR key
*/
public static final void encXORPass(byte[] raw, final int offset, final int size, int key)
{
int stop = size - 8;
int pos = 4 + offset;
int edx;
int ecx = key; // Initial xor key
while (pos < stop)
{
edx = (raw[pos] & 0xFF);
edx |= (raw[pos + 1] & 0xFF) << 8;
edx |= (raw[pos + 2] & 0xFF) << 16;
edx |= (raw[pos + 3] & 0xFF) << 24;
ecx += edx;
edx ^= ecx;
raw[pos++] = (byte) (edx & 0xFF);
raw[pos++] = (byte) ((edx >> 8) & 0xFF);
raw[pos++] = (byte) ((edx >> 16) & 0xFF);
raw[pos++] = (byte) ((edx >> 24) & 0xFF);
}
raw[pos++] = (byte) (ecx & 0xFF);
raw[pos++] = (byte) ((ecx >> 8) & 0xFF);
raw[pos++] = (byte) ((ecx >> 16) & 0xFF);
raw[pos++] = (byte) ((ecx >> 24) & 0xFF);
}
public final byte[] decrypt(byte[] raw) throws IOException
{
byte[] result = new byte[raw.length];
int count = raw.length / 8;
for (int i = 0; i < count; i++)
{
_decrypt.processBlock(raw, i * 8, result, i * 8);
}
return result;
}
public final void decrypt(byte[] raw, final int offset, final int size) throws IOException
{
byte[] result = new byte[size];
int count = size / 8;
for (int i = 0; i < count; i++)
{
_decrypt.processBlock(raw, offset + (i * 8), result, i * 8);
}
System.arraycopy(result, 0, raw, offset, size);
}
public final byte[] crypt(byte[] raw) throws IOException
{
int count = raw.length / 8;
byte[] result = new byte[raw.length];
for (int i = 0; i < count; i++)
{
_crypt.processBlock(raw, i * 8, result, i * 8);
}
return result;
}
public final void crypt(byte[] raw, final int offset, final int size) throws IOException
{
int count = size / 8;
byte[] result = new byte[size];
for (int i = 0; i < count; i++)
{
_crypt.processBlock(raw, offset + (i * 8), result, i * 8);
}
System.arraycopy(result, 0, raw, offset, size);
}
}