void ExpandKey(byte[] key, byte[] salt, EksBlowfishKeyExpansionFlags flags)
{
uint[] p = P; uint[][] s = S;
int i, j, k; uint data, datal, datar;
j = 0;
for (i = 0; i < p.Length; i++)
{
data = 0x00000000;
for (k = 0; k < 4; k++)
{
if ((flags & EksBlowfishKeyExpansionFlags.EmulateCryptBlowfishSignExtensionBug) != 0)
{
data = (data << 8) | (uint)(int)(sbyte)key[j];
}
else
{
data = (data << 8) | key[j];
}
j = (j + 1) % key.Length;
}
p[i] = p[i] ^ data;
}
uint saltL0 = BitPacking.UInt32FromBEBytes(salt, 0);
uint saltR0 = BitPacking.UInt32FromBEBytes(salt, 4);
uint saltL1 = BitPacking.UInt32FromBEBytes(salt, 8);
uint saltR1 = BitPacking.UInt32FromBEBytes(salt, 12);
datal = 0x00000000;
datar = 0x00000000;
for (i = 0; i < p.Length; i += 4)
{
datal ^= saltL0; datar ^= saltR0;
Encipher(ref datal, ref datar); p[i + 0] = datal; p[i + 1] = datar;
if (i + 2 == p.Length)
{
break;
} // 18 here
datal ^= saltL1; datar ^= saltR1;
Encipher(ref datal, ref datar); p[i + 2] = datal; p[i + 3] = datar;
}
for (i = 0; i < s.Length; i++)
{
uint[] sb = s[i];
for (j = 0; j < sb.Length; j += 4)
{
datal ^= saltL1; datar ^= saltR1;
Encipher(ref datal, ref datar); sb[j + 0] = datal; sb[j + 1] = datar;
datal ^= saltL0; datar ^= saltR0;
Encipher(ref datal, ref datar); sb[j + 2] = datal; sb[j + 3] = datar;
}
}
}
static BlowfishCipher()
{
byte[] magicBytes = Encoding.ASCII.GetBytes(BCryptMagic);
Array.Resize(ref magicBytes, (magicBytes.Length + 7) / 8 * 8);
Magic = new uint[(magicBytes.Length + 3) / 4];
for (int i = 0; i < Magic.Length; i++)
{
Magic[i] = BitPacking.UInt32FromBEBytes(magicBytes, i * 4);
}
}
/// <summary>
/// Reverses the encipherment of eight bytes of data from one buffer and places the result in another buffer.
/// </summary>
/// <param name="inputBuffer">The buffer to read enciphered data from.</param>
/// <param name="inputOffset">The offset of the first enciphered byte.</param>
/// <param name="outputBuffer">The buffer to write plaintext data to.</param>
/// <param name="outputOffset">The offset at which to place the first plaintext byte.</param>
public void Decipher
(byte[] inputBuffer, int inputOffset,
byte[] outputBuffer, int outputOffset)
{
CheckCipherBuffers(inputBuffer, inputOffset, outputBuffer, outputOffset);
uint xl = BitPacking.UInt32FromBEBytes(inputBuffer, inputOffset + 0);
uint xr = BitPacking.UInt32FromBEBytes(inputBuffer, inputOffset + 4);
Decipher(ref xl, ref xr);
BitPacking.BEBytesFromUInt32(xl, outputBuffer, outputOffset + 0);
BitPacking.BEBytesFromUInt32(xr, outputBuffer, outputOffset + 4);
}
