/***********************************************************************************************************/
#region ------ Constructor ------
/// <summary>
/// Constructs and initializes a blowfish instance with the supplied secret string.
/// </summary>
/// <param name="secretKey">The secret string to cipher with.</param>
public BlowfishSymmetricCipher(string secretKey)
{
short i, j, k;
uint data, datal, datar;
// Convert secret string into a byte array.
byte[] key = SerializeDeserializeObject.StringToUTF8ByteArray(secretKey);
P = _P.Clone() as uint[];
S = _S.Clone() as uint[, ];
j = 0;
for (i = 0; i < N + 2; i++)
{
data = 0x00000000;
for (k = 0; k < 4; k++)
{
data = (data << 8) | key[j];
j++;
if (j >= key.Length)
{
j = 0;
}
}
P[i] = P[i] ^ data;
}
datal = 0x00000000;
datar = 0x00000000;
for (i = 0; i < N + 2; i += 2)
{
Encipher(ref datal, ref datar);
P[i] = datal;
P[i + 1] = datar;
}
for (i = 0; i < 4; i++)
{
for (j = 0; j < 256; j += 2)
{
Encipher(ref datal, ref datar);
S[i, j] = datal;
S[i, j + 1] = datar;
}
}
}
/***********************************************************************************************************/
#region ------ Public Methods ------
/// <summary>
/// Encrypts a byte array in place.
/// </summary>
/// <param name="data">The array to encrypt.</param>
/// <param name="length">The amount to encrypt.</param>
public void Encipher(ref byte[] data, int length)
{
uint xl;
uint xr;
while ((length % 8) != 0)
{
byte[] addonByte = SerializeDeserializeObject.StringToUTF8ByteArray(" ");
length += addonByte.Length;
Array.Resize <byte>(ref data, length);
for (int i = 0; i < addonByte.Length; i++)
{
data[length - 1 + i] = addonByte[i];
}
}
for (int i = 0; i < length; i += 8)
{
// Encode the data in 8 byte blocks.
xl = (uint)((data[i] << 24) | (data[i + 1] << 16) | (data[i + 2] << 8) | data[i + 3]);
xr = (uint)((data[i + 4] << 24) | (data[i + 5] << 16) | (data[i + 6] << 8) | data[i + 7]);
Encipher(ref xl, ref xr);
// Now Replace the data.
data[i] = (byte)(xl >> 24);
data[i + 1] = (byte)(xl >> 16);
data[i + 2] = (byte)(xl >> 8);
data[i + 3] = (byte)(xl);
data[i + 4] = (byte)(xr >> 24);
data[i + 5] = (byte)(xr >> 16);
data[i + 6] = (byte)(xr >> 8);
data[i + 7] = (byte)(xr);
}
}