{                    W[j][i] = inv_mcol(W[j][i]);                }            }        }        return W;    }    private int         ROUNDS;    private int[][]     WorkingKey = null;    private int         C0, C1, C2, C3;    private boolean     forEncryption;    private static final int BLOCK_SIZE = 16;    /**     * default constructor - 128 bit block size.     */    public AESLightEngine()    {    }    /**     * initialise an AES cipher.     *     * @param forEncryption whether or not we are for encryption.     * @param params the parameters required to set up the cipher.     * @exception IllegalArgumentException if the params argument is     * inappropriate.     */    public void init(        boolean           forEncryption,        CipherParameters  params)    {        if (params instanceof KeyParameter)        {            WorkingKey = generateWorkingKey(((KeyParameter)params).getKey(), forEncryption);            this.forEncryption = forEncryption;            return;        }        throw new IllegalArgumentException("invalid parameter passed to AES init - " + params.getClass().getName());    }    public String getAlgorithmName()    {        return "AES";    }    public int getBlockSize()    {        return BLOCK_SIZE;    }    public int processBlock(        byte[] in,        int inOff,        byte[] out,        int outOff)    {        if (WorkingKey == null)        {            throw new IllegalStateException("AES engine not initialised");        }        if ((inOff + (32 / 2)) > in.length)        {            throw new DataLengthException("input buffer too short");        }        if ((outOff + (32 / 2)) > out.length)        {            throw new DataLengthException("output buffer too short");        }        if (forEncryption)        {            unpackBlock(in, inOff);            encryptBlock(WorkingKey);            packBlock(out, outOff);        }        else        {            unpackBlock(in, inOff);            decryptBlock(WorkingKey);            packBlock(out, outOff);        }        return BLOCK_SIZE;    }    public void reset()    {    }    private final void unpackBlock(        byte[]      bytes,        int         off)    {        int     index = off;        C0 = (bytes[index++] & 0xff);        C0 |= (bytes[index++] & 0xff) << 8;        C0 |= (bytes[index++] & 0xff) << 16;        C0 |= bytes[index++] << 24;        C1 = (bytes[index++] & 0xff);        C1 |= (bytes[index++] & 0xff) << 8;        C1 |= (bytes[index++] & 0xff) << 16;        C1 |= bytes[index++] << 24;        C2 = (bytes[index++] & 0xff);        C2 |= (bytes[index++] & 0xff) << 8;        C2 |= (bytes[index++] & 0xff) << 16;        C2 |= bytes[index++] << 24;        C3 = (bytes[index++] & 0xff);        C3 |= (bytes[index++] & 0xff) << 8;        C3 |= (bytes[index++] & 0xff) << 16;        C3 |= bytes[index++] << 24;    }    private final void packBlock(        byte[]      bytes,        int         off)    {        int     index = off;        bytes[index++] = (byte)C0;        bytes[index++] = (byte)(C0 >> 8);        bytes[index++] = (byte)(C0 >> 16);        bytes[index++] = (byte)(C0 >> 24);        bytes[index++] = (byte)C1;        bytes[index++] = (byte)(C1 >> 8);        bytes[index++] = (byte)(C1 >> 16);        bytes[index++] = (byte)(C1 >> 24);        bytes[index++] = (byte)C2;        bytes[index++] = (byte)(C2 >> 8);        bytes[index++] = (byte)(C2 >> 16);        bytes[index++] = (byte)(C2 >> 24);        bytes[index++] = (byte)C3;        bytes[index++] = (byte)(C3 >> 8);        bytes[index++] = (byte)(C3 >> 16);        bytes[index++] = (byte)(C3 >> 24);    }    private void encryptBlock(int[][] KW)    {        int r, r0, r1, r2, r3;        C0 ^= KW[0][0];        C1 ^= KW[0][1];        C2 ^= KW[0][2];        C3 ^= KW[0][3];        for (r = 1; r < ROUNDS - 1;)        {            r0 = mcol((S[C0&255]&255) ^ ((S[(C1>>8)&255]&255)<<8) ^ ((S[(C2>>16)&255]&255)<<16) ^ (S[(C3>>24)&255]<<24)) ^ KW[r][0];            r1 = mcol((S[C1&255]&255) ^ ((S[(C2>>8)&255]&255)<<8) ^ ((S[(C3>>16)&255]&255)<<16) ^ (S[(C0>>24)&255]<<24)) ^ KW[r][1];            r2 = mcol((S[C2&255]&255) ^ ((S[(C3>>8)&255]&255)<<8) ^ ((S[(C0>>16)&255]&255)<<16) ^ (S[(C1>>24)&255]<<24)) ^ KW[r][2];            r3 = mcol((S[C3&255]&255) ^ ((S[(C0>>8)&255]&255)<<8) ^ ((S[(C1>>16)&255]&255)<<16) ^ (S[(C2>>24)&255]<<24)) ^ KW[r++][3];            C0 = mcol((S[r0&255]&255) ^ ((S[(r1>>8)&255]&255)<<8) ^ ((S[(r2>>16)&255]&255)<<16) ^ (S[(r3>>24)&255]<<24)) ^ KW[r][0];            C1 = mcol((S[r1&255]&255) ^ ((S[(r2>>8)&255]&255)<<8) ^ ((S[(r3>>16)&255]&255)<<16) ^ (S[(r0>>24)&255]<<24)) ^ KW[r][1];            C2 = mcol((S[r2&255]&255) ^ ((S[(r3>>8)&255]&255)<<8) ^ ((S[(r0>>16)&255]&255)<<16) ^ (S[(r1>>24)&255]<<24)) ^ KW[r][2];            C3 = mcol((S[r3&255]&255) ^ ((S[(r0>>8)&255]&255)<<8) ^ ((S[(r1>>16)&255]&255)<<16) ^ (S[(r2>>24)&255]<<24)) ^ KW[r++][3];        }        r0 = mcol((S[C0&255]&255) ^ ((S[(C1>>8)&255]&255)<<8) ^ ((S[(C2>>16)&255]&255)<<16) ^ (S[(C3>>24)&255]<<24)) ^ KW[r][0];        r1 = mcol((S[C1&255]&255) ^ ((S[(C2>>8)&255]&255)<<8) ^ ((S[(C3>>16)&255]&255)<<16) ^ (S[(C0>>24)&255]<<24)) ^ KW[r][1];        r2 = mcol((S[C2&255]&255) ^ ((S[(C3>>8)&255]&255)<<8) ^ ((S[(C0>>16)&255]&255)<<16) ^ (S[(C1>>24)&255]<<24)) ^ KW[r][2];        r3 = mcol((S[C3&255]&255) ^ ((S[(C0>>8)&255]&255)<<8) ^ ((S[(C1>>16)&255]&255)<<16) ^ (S[(C2>>24)&255]<<24)) ^ KW[r++][3];        // the final round is a simple function of S        C0 = (S[r0&255]&255) ^ ((S[(r1>>8)&255]&255)<<8) ^ ((S[(r2>>16)&255]&255)<<16) ^ (S[(r3>>24)&255]<<24) ^ KW[r][0];        C1 = (S[r1&255]&255) ^ ((S[(r2>>8)&255]&255)<<8) ^ ((S[(r3>>16)&255]&255)<<16) ^ (S[(r0>>24)&255]<<24) ^ KW[r][1];        C2 = (S[r2&255]&255) ^ ((S[(r3>>8)&255]&255)<<8) ^ ((S[(r0>>16)&255]&255)<<16) ^ (S[(r1>>24)&255]<<24) ^ KW[r][2];        C3 = (S[r3&255]&255) ^ ((S[(r0>>8)&255]&255)<<8) ^ ((S[(r1>>16)&255]&255)<<16) ^ (S[(r2>>24)&255]<<24) ^ KW[r][3];    }    private final void decryptBlock(int[][] KW)    {        int r, r0, r1, r2, r3;        C0 ^= KW[ROUNDS][0];        C1 ^= KW[ROUNDS][1];        C2 ^= KW[ROUNDS][2];        C3 ^= KW[ROUNDS][3];        for (r = ROUNDS-1; r>1;)        {            r0 = inv_mcol((Si[C0&255]&255) ^ ((Si[(C3>>8)&255]&255)<<8) ^ ((Si[(C2>>16)&255]&255)<<16) ^ (Si[(C1>>24)&255]<<24)) ^ KW[r][0];            r1 = inv_mcol((Si[C1&255]&255) ^ ((Si[(C0>>8)&255]&255)<<8) ^ ((Si[(C3>>16)&255]&255)<<16) ^ (Si[(C2>>24)&255]<<24)) ^ KW[r][1];            r2 = inv_mcol((Si[C2&255]&255) ^ ((Si[(C1>>8)&255]&255)<<8) ^ ((Si[(C0>>16)&255]&255)<<16) ^ (Si[(C3>>24)&255]<<24)) ^ KW[r][2];            r3 = inv_mcol((Si[C3&255]&255) ^ ((Si[(C2>>8)&255]&255)<<8) ^ ((Si[(C1>>16)&255]&255)<<16) ^ (Si[(C0>>24)&255]<<24)) ^ KW[r--][3];            C0 = inv_mcol((Si[r0&255]&255) ^ ((Si[(r3>>8)&255]&255)<<8) ^ ((Si[(r2>>16)&255]&255)<<16) ^ (Si[(r1>>24)&255]<<24)) ^ KW[r][0];            C1 = inv_mcol((Si[r1&255]&255) ^ ((Si[(r0>>8)&255]&255)<<8) ^ ((Si[(r3>>16)&255]&255)<<16) ^ (Si[(r2>>24)&255]<<24)) ^ KW[r][1];            C2 = inv_mcol((Si[r2&255]&255) ^ ((Si[(r1>>8)&255]&255)<<8) ^ ((Si[(r0>>16)&255]&255)<<16) ^ (Si[(r3>>24)&255]<<24)) ^ KW[r][2];            C3 = inv_mcol((Si[r3&255]&255) ^ ((Si[(r2>>8)&255]&255)<<8) ^ ((Si[(r1>>16)&255]&255)<<16) ^ (Si[(r0>>24)&255]<<24)) ^ KW[r--][3];        }        r0 = inv_mcol((Si[C0&255]&255) ^ ((Si[(C3>>8)&255]&255)<<8) ^ ((Si[(C2>>16)&255]&255)<<16) ^ (Si[(C1>>24)&255]<<24)) ^ KW[r][0];        r1 = inv_mcol((Si[C1&255]&255) ^ ((Si[(C0>>8)&255]&255)<<8) ^ ((Si[(C3>>16)&255]&255)<<16) ^ (Si[(C2>>24)&255]<<24)) ^ KW[r][1];        r2 = inv_mcol((Si[C2&255]&255) ^ ((Si[(C1>>8)&255]&255)<<8) ^ ((Si[(C0>>16)&255]&255)<<16) ^ (Si[(C3>>24)&255]<<24)) ^ KW[r][2];        r3 = inv_mcol((Si[C3&255]&255) ^ ((Si[(C2>>8)&255]&255)<<8) ^ ((Si[(C1>>16)&255]&255)<<16) ^ (Si[(C0>>24)&255]<<24)) ^ KW[r--][3];        // the final round's table is a simple function of Si        C0 = (Si[r0&255]&255) ^ ((Si[(r3>>8)&255]&255)<<8) ^ ((Si[(r2>>16)&255]&255)<<16) ^ (Si[(r1>>24)&255]<<24) ^ KW[0][0];        C1 = (Si[r1&255]&255) ^ ((Si[(r0>>8)&255]&255)<<8) ^ ((Si[(r3>>16)&255]&255)<<16) ^ (Si[(r2>>24)&255]<<24) ^ KW[0][1];        C2 = (Si[r2&255]&255) ^ ((Si[(r1>>8)&255]&255)<<8) ^ ((Si[(r0>>16)&255]&255)<<16) ^ (Si[(r3>>24)&255]<<24) ^ KW[0][2];        C3 = (Si[r3&255]&255) ^ ((Si[(r2>>8)&255]&255)<<8) ^ ((Si[(r1>>16)&255]&255)<<16) ^ (Si[(r0>>24)&255]<<24) ^ KW[0][3];    }}