desengine.java

来自「jtds的源码 是你学习java的好东西」· Java 代码 · 共 518 行 · 第 1/2 页

        0x02080000, 0x00000000, 0x40080000, 0x42000000,
        0x00080100, 0x02000100, 0x40000100, 0x00080000,
        0x00000000, 0x40080000, 0x02080100, 0x40000100
    };

    static int[] SP6 = {
        0x20000010, 0x20400000, 0x00004000, 0x20404010,
        0x20400000, 0x00000010, 0x20404010, 0x00400000,
        0x20004000, 0x00404010, 0x00400000, 0x20000010,
        0x00400010, 0x20004000, 0x20000000, 0x00004010,
        0x00000000, 0x00400010, 0x20004010, 0x00004000,
        0x00404000, 0x20004010, 0x00000010, 0x20400010,
        0x20400010, 0x00000000, 0x00404010, 0x20404000,
        0x00004010, 0x00404000, 0x20404000, 0x20000000,
        0x20004000, 0x00000010, 0x20400010, 0x00404000,
        0x20404010, 0x00400000, 0x00004010, 0x20000010,
        0x00400000, 0x20004000, 0x20000000, 0x00004010,
        0x20000010, 0x20404010, 0x00404000, 0x20400000,
        0x00404010, 0x20404000, 0x00000000, 0x20400010,
        0x00000010, 0x00004000, 0x20400000, 0x00404010,
        0x00004000, 0x00400010, 0x20004010, 0x00000000,
        0x20404000, 0x20000000, 0x00400010, 0x20004010
    };

    static int[] SP7 = {
        0x00200000, 0x04200002, 0x04000802, 0x00000000,
        0x00000800, 0x04000802, 0x00200802, 0x04200800,
        0x04200802, 0x00200000, 0x00000000, 0x04000002,
        0x00000002, 0x04000000, 0x04200002, 0x00000802,
        0x04000800, 0x00200802, 0x00200002, 0x04000800,
        0x04000002, 0x04200000, 0x04200800, 0x00200002,
        0x04200000, 0x00000800, 0x00000802, 0x04200802,
        0x00200800, 0x00000002, 0x04000000, 0x00200800,
        0x04000000, 0x00200800, 0x00200000, 0x04000802,
        0x04000802, 0x04200002, 0x04200002, 0x00000002,
        0x00200002, 0x04000000, 0x04000800, 0x00200000,
        0x04200800, 0x00000802, 0x00200802, 0x04200800,
        0x00000802, 0x04000002, 0x04200802, 0x04200000,
        0x00200800, 0x00000000, 0x00000002, 0x04200802,
        0x00000000, 0x00200802, 0x04200000, 0x00000800,
        0x04000002, 0x04000800, 0x00000800, 0x00200002
    };

    static int[] SP8 = {
        0x10001040, 0x00001000, 0x00040000, 0x10041040,
        0x10000000, 0x10001040, 0x00000040, 0x10000000,
        0x00040040, 0x10040000, 0x10041040, 0x00041000,
        0x10041000, 0x00041040, 0x00001000, 0x00000040,
        0x10040000, 0x10000040, 0x10001000, 0x00001040,
        0x00041000, 0x00040040, 0x10040040, 0x10041000,
        0x00001040, 0x00000000, 0x00000000, 0x10040040,
        0x10000040, 0x10001000, 0x00041040, 0x00040000,
        0x00041040, 0x00040000, 0x10041000, 0x00001000,
        0x00000040, 0x10040040, 0x00001000, 0x00041040,
        0x10001000, 0x00000040, 0x10000040, 0x10040000,
        0x10040040, 0x10000000, 0x00040000, 0x10001040,
        0x00000000, 0x10041040, 0x00040040, 0x10000040,
        0x10040000, 0x10001000, 0x10001040, 0x00000000,
        0x10041040, 0x00041000, 0x00041000, 0x00001040,
        0x00001040, 0x00040040, 0x10000000, 0x10041000
    };

    /**
     * generate an integer based working key based on our secret key
     * and what we processing we are planning to do.
     *
     * Acknowledgements for this routine go to James Gillogly & Phil Karn.
     *         (whoever, and wherever they are!).
     */
    protected int[] generateWorkingKey(
        boolean encrypting,
        byte[]  key)
    {
        int[]       newKey = new int[32];
        boolean[]   pc1m = new boolean[56],
                    pcr = new boolean[56];

        for (int j = 0; j < 56; j++ )
        {
            int    l = pc1[j];

            pc1m[j] = ((key[l >>> 3] & bytebit[l & 07]) != 0);
        }

        for (int i = 0; i < 16; i++)
        {
            int    l, m, n;

            if (encrypting)
            {
                m = i << 1;
            }
            else
            {
                m = (15 - i) << 1;
            }

            n = m + 1;
            newKey[m] = newKey[n] = 0;

            for (int j = 0; j < 28; j++)
            {
                l = j + totrot[i];
                if ( l < 28 )
                {
                    pcr[j] = pc1m[l];
                }
                else
                {
                    pcr[j] = pc1m[l - 28];
                }
            }

            for (int j = 28; j < 56; j++)
            {
                l = j + totrot[i];
                if (l < 56 )
                {
                    pcr[j] = pc1m[l];
                }
                else
                {
                    pcr[j] = pc1m[l - 28];
                }
            }

            for (int j = 0; j < 24; j++)
            {
                if (pcr[pc2[j]])
                {
                    newKey[m] |= bigbyte[j];
                }

                if (pcr[pc2[j + 24]])
                {
                    newKey[n] |= bigbyte[j];
                }
            }
        }

        //
        // store the processed key
        //
        for (int i = 0; i != 32; i += 2)
        {
            int    i1, i2;

            i1 = newKey[i];
            i2 = newKey[i + 1];

            newKey[i] = ((i1 & 0x00fc0000) << 6) | ((i1 & 0x00000fc0) << 10)
                                   | ((i2 & 0x00fc0000) >>> 10) | ((i2 & 0x00000fc0) >>> 6);

            newKey[i + 1] = ((i1 & 0x0003f000) << 12) | ((i1 & 0x0000003f) << 16)
                                   | ((i2 & 0x0003f000) >>> 4) | (i2 & 0x0000003f);
        }

        return newKey;
    }

    /**
     * the DES engine.
     */
    protected void desFunc(
        int[]   wKey,
        byte[]  in,
        int     inOff,
        byte[]  out,
        int     outOff)
    {
        int     work, right, left;

        left     = (in[inOff + 0] & 0xff) << 24;
        left    |= (in[inOff + 1] & 0xff) << 16;
        left    |= (in[inOff + 2] & 0xff) << 8;
        left    |= (in[inOff + 3] & 0xff);

        right     = (in[inOff + 4] & 0xff) << 24;
        right    |= (in[inOff + 5] & 0xff) << 16;
        right    |= (in[inOff + 6] & 0xff) << 8;
        right    |= (in[inOff + 7] & 0xff);

        work = ((left >>> 4) ^ right) & 0x0f0f0f0f;
        right ^= work;
        left ^= (work << 4);
        work = ((left >>> 16) ^ right) & 0x0000ffff;
        right ^= work;
        left ^= (work << 16);
        work = ((right >>> 2) ^ left) & 0x33333333;
        left ^= work;
        right ^= (work << 2);
        work = ((right >>> 8) ^ left) & 0x00ff00ff;
        left ^= work;
        right ^= (work << 8);
        right = ((right << 1) | ((right >>> 31) & 1)) & 0xffffffff;
        work = (left ^ right) & 0xaaaaaaaa;
        left ^= work;
        right ^= work;
        left = ((left << 1) | ((left >>> 31) & 1)) & 0xffffffff;

        for (int round = 0; round < 8; round++)
        {
            int     fval;

            work  = (right << 28) | (right >>> 4);
            work ^= wKey[round * 4 + 0];
            fval  = SP7[ work      & 0x3f];
            fval |= SP5[(work >>>  8) & 0x3f];
            fval |= SP3[(work >>> 16) & 0x3f];
            fval |= SP1[(work >>> 24) & 0x3f];
            work  = right ^ wKey[round * 4 + 1];
            fval |= SP8[ work      & 0x3f];
            fval |= SP6[(work >>>  8) & 0x3f];
            fval |= SP4[(work >>> 16) & 0x3f];
            fval |= SP2[(work >>> 24) & 0x3f];
            left ^= fval;
            work  = (left << 28) | (left >>> 4);
            work ^= wKey[round * 4 + 2];
            fval  = SP7[ work      & 0x3f];
            fval |= SP5[(work >>>  8) & 0x3f];
            fval |= SP3[(work >>> 16) & 0x3f];
            fval |= SP1[(work >>> 24) & 0x3f];
            work  = left ^ wKey[round * 4 + 3];
            fval |= SP8[ work      & 0x3f];
            fval |= SP6[(work >>>  8) & 0x3f];
            fval |= SP4[(work >>> 16) & 0x3f];
            fval |= SP2[(work >>> 24) & 0x3f];
            right ^= fval;
        }

        right = (right << 31) | (right >>> 1);
        work = (left ^ right) & 0xaaaaaaaa;
        left ^= work;
        right ^= work;
        left = (left << 31) | (left >>> 1);
        work = ((left >>> 8) ^ right) & 0x00ff00ff;
        right ^= work;
        left ^= (work << 8);
        work = ((left >>> 2) ^ right) & 0x33333333;
        right ^= work;
        left ^= (work << 2);
        work = ((right >>> 16) ^ left) & 0x0000ffff;
        left ^= work;
        right ^= (work << 16);
        work = ((right >>> 4) ^ left) & 0x0f0f0f0f;
        left ^= work;
        right ^= (work << 4);

        out[outOff + 0] = (byte)((right >>> 24) & 0xff);
        out[outOff + 1] = (byte)((right >>> 16) & 0xff);
        out[outOff + 2] = (byte)((right >>>  8) & 0xff);
        out[outOff + 3] = (byte)( right         & 0xff);
        out[outOff + 4] = (byte)((left >>> 24) & 0xff);
        out[outOff + 5] = (byte)((left >>> 16) & 0xff);
        out[outOff + 6] = (byte)((left >>>  8) & 0xff);
        out[outOff + 7] = (byte)( left         & 0xff);
    }
}