public static void Encrypt(byte[] data)
        {
            uint blockIndex;
            uint keyIndex;
            GetKeyTableIndex(data.Length, out blockIndex, out keyIndex);
            Encrypt(data, blockIndex, keyIndex);
        }

public static void Encrypt(byte[] data, uint blockIndex, uint keyIndex)
        {
            for (var i = 0; i < data.Length; i++)
            {
                data[i] ^= KeyTable[blockIndex][keyIndex][i % 40];
                data[i] = (byte)(((data[i] & 0x80) >> 7) & 1 | (data[i] << 1) & 0xFE);
            }
        }