public static byte[] DecryptBlock(uint[] v, uint[] k)
{
if (v == null || k == null)
{
return(null);
}
if (k.Length < 4)
{
return(null);
}
uint n = (uint)v.Length;
if (n == 0)
{
return(null);
}
if (n <= 1)
{
return new byte[1] {
0
}
}
; // algorithm doesn't work for n<2 so fudge by adding a null
uint q = (uint)(6 + 52 / n);
n--;
uint z = v[n], y = v[0];
uint mx, e, sum = q * DELTA;
uint p = 0;
while (sum != 0)
{
e = sum >> 2 & 3;
for (p = n; p > 0; p--)
{
z = v[p - 1];
mx = (z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z);
y = v[p] -= mx;
}
z = v[n];
mx = (z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z);
y = v[0] -= mx;
sum -= DELTA;
}
return(StrConvert.LongsToStr(v));
}
public static byte[] EncryptBlock(uint[] v, uint[] k)
{
if (v == null || k == null)
{
return(null);
}
if (k.Length < 4)
{
return(null);
}
int n = v.Length;
if (n == 0)
{
return(null);
}
if (n <= 1)
{
return new byte[1] {
0
}
}
; // algorithm doesn't work for n<2 so fudge by adding a null
uint q = (uint)(6 + 52 / n);
n--;
uint z = v[n], y = v[0];
uint mx, e, sum = 0;
while (q-- > 0)
{ // 6 + 52/n operations gives between 6 & 32 mixes on each word
sum += DELTA;
e = sum >> 2 & 3;
for (int p = 0; p < n; p++)
{
y = v[p + 1];
mx = (z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z);
z = v[p] += mx;
}
y = v[0];
mx = (z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[n & 3 ^ e] ^ z);
z = v[n] += mx;
}
return(StrConvert.LongsToStr(v));
}
