public override void CryptApiData(DRIS dris, byte[] data, int length, int alg_answer)
{
int i, j, k;
var bigseed = new byte[256];
var S = new byte[256];
byte temp, t;
for (i = 0; i < 256; i += 8)
{
dris.Set4Bytes(bigseed, i, dris.seed1);
dris.Set4Bytes(bigseed, i + 4, dris.seed2);
}
for (i = 0; i < 256; i++)
{
S[i] = (byte)i;
}
for (i = 0, j = 0; i < 256; i++)
{
j = (j + S[i] + bigseed[i] + 7) % 256;
temp = S[i];
S[i] = S[j];
S[j] = temp;
}
for (i = 0, j = 0, k = 0; k < length; k++)
{
i = (i + 1) % 256;
j = (j + S[i] + 71) % 256;
temp = S[i];
S[i] = S[j];
S[j] = temp;
t = (byte)(S[i] + S[j] + 16);
data[k] ^= S[t];
}
}
public override void CryptDRIS(DRIS dris)
{
int i, j, k;
var bigseed = new byte[256];
var S = new byte[256];
byte temp, t;
var dris_bytes = new byte[Marshal.SizeOf(dris)];
dris.DrisToByteArray(dris, dris_bytes); // convert DRIS to byte array so we can encrypt it
for (i = 0; i < 256; i += 8)
{
dris.Set4Bytes(bigseed, i, dris.seed1);
dris.Set4Bytes(bigseed, i + 4, dris.seed2);
}
for (i = 0; i < 256; i++)
{
S[i] = (byte)i;
}
for (i = 0, j = 0; i < 256; i++)
{
j = (j + S[i] + bigseed[i] + 11) % 256;
temp = S[i];
S[i] = S[j];
S[j] = temp;
}
for (i = 0, j = 0, k = 16; k < Marshal.SizeOf(dris); k++)
{
i = (i + 1) % 256;
j = (j + S[i] + 37) % 256;
temp = S[i];
S[i] = S[j];
S[j] = temp;
t = (byte)(S[i] + S[j] + 17);
dris_bytes[k] ^= S[t];
}
dris.ByteArrayToDris(dris_bytes, dris); // convert it back again
}