desFunc method

void desFunc(List<int> wKey, Uint8List inp, int inOff, Uint8List out, int outOff,)

Implementation

void desFunc(
  List<int> wKey,
  Uint8List inp,
  int inOff,
  Uint8List out,
  int outOff,
) {
  int work, right, left;

  left = _bigEndianToInt(inp, inOff);
  right = _bigEndianToInt(inp, inOff + 4);

  work = ((shiftr32(left, 4)) ^ right) & 0x0f0f0f0f;
  right ^= work;
  left ^= shiftl32(work, 4);
  work = ((shiftr32(left, 16)) ^ right) & 0x0000ffff;
  right ^= work;
  left ^= shiftl32(work, 16);
  work = ((shiftr32(right, 2)) ^ left) & 0x33333333;
  left ^= work;
  right ^= shiftl32(work, 2);
  work = ((shiftr32(right, 8)) ^ left) & 0x00ff00ff;
  left ^= work;
  right ^= shiftl32(work, 8);
  right = (shiftl32(right, 1)) | (shiftr32(right, 31));
  work = (left ^ right) & 0xaaaaaaaa;
  left ^= work;
  right ^= work;
  left = (shiftl32(left, 1)) | (shiftr32(left, 31));

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

    work = (shiftl32(right, 28)) | (shiftr32(right, 4));
    work ^= wKey[round * 4 + 0];
    fval = SP7[work & 0x3f];
    fval |= SP5[(shiftr32(work, 8)) & 0x3f];
    fval |= SP3[(shiftr32(work, 16)) & 0x3f];
    fval |= SP1[(shiftr32(work, 24)) & 0x3f];
    work = right ^ wKey[round * 4 + 1];
    fval |= SP8[work & 0x3f];
    fval |= SP6[(shiftr32(work, 8)) & 0x3f];
    fval |= SP4[(shiftr32(work, 16)) & 0x3f];
    fval |= SP2[(shiftr32(work, 24)) & 0x3f];
    left ^= fval;
    work = (shiftl32(left, 28)) | (shiftr32(left, 4));
    work ^= wKey[round * 4 + 2];
    fval = SP7[work & 0x3f];
    fval |= SP5[(shiftr32(work, 8)) & 0x3f];
    fval |= SP3[(shiftr32(work, 16)) & 0x3f];
    fval |= SP1[(shiftr32(work, 24)) & 0x3f];
    work = left ^ wKey[round * 4 + 3];
    fval |= SP8[work & 0x3f];
    fval |= SP6[(shiftr32(work, 8)) & 0x3f];
    fval |= SP4[(shiftr32(work, 16)) & 0x3f];
    fval |= SP2[(shiftr32(work, 24)) & 0x3f];
    right ^= fval;
  }
  right = (shiftl32(right, 31)) | (shiftr32(right, 1));
  work = (left ^ right) & 0xaaaaaaaa;
  left ^= work;
  right ^= work;
  left = (shiftl32(left, 31)) | (shiftr32(left, 1));
  work = ((shiftr32(left, 8)) ^ right) & 0x00ff00ff;
  right ^= work;
  left ^= shiftl32(work, 8);
  work = ((shiftr32(left, 2)) ^ right) & 0x33333333;
  right ^= work;
  left ^= shiftl32(work, 2);
  work = ((shiftr32(right, 16)) ^ left) & 0x0000ffff;
  left ^= work;
  right ^= shiftl32(work, 16);
  work = ((shiftr32(right, 4)) ^ left) & 0x0f0f0f0f;
  left ^= work;
  right ^= shiftl32(work, 4);

  _intToBigEndian(right, out, outOff);
  _intToBigEndian(left, out, outOff + 4);
}