desengine.java

这是linux下ssl vpn的实现程序

  };

  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);
  }
}