/// <summary>
/// Uses the RDRAND instrution on Intel IvyBridge and higher CPUs
/// to return truely random integers.
///
/// CAUTION: If this code is executed
/// on non IvyBridge CPUs, it will return null!
/// </summary>
/// <returns>Random unsigned integer, or 0 if no executing on compatible CPU</returns>
public static uint GenerateUnsignedInt()
{
if (!RdRandLib.GeneratorAvailable())
{
return(0);
}
uint rnd = RdRandLib.Random32();
return(rnd);
}
/// <summary>
/// Uses the RDRAND instrution on Intel IvyBridge and higher CPUs
/// to return truely random byte arrays.
///
/// CAUTION: If this code is executed
/// on non IvyBridge CPUs, it will return null!
/// </summary>
/// <param name="length">Size of the byte array</param>
/// <returns>Random byte array, or null if no executing on compatible CPU</returns>
public static byte[] GenerateBytes(int length)
{
if (!RdRandLib.GeneratorAvailable())
{
return(null);
}
int numInts = length / 4 + 1;
int idx = 0;
byte[] r = new byte[length];
for (int i = 0; i < numInts; i++)
{
uint rnd = RdRandLib.Random32();
byte[] tmp = IntToBytes(rnd);
if (idx >= length)
{
return(r);
}
r[idx++] = tmp[0];
if (idx >= length)
{
return(r);
}
r[idx++] = tmp[1];
if (idx >= length)
{
return(r);
}
r[idx++] = tmp[2];
if (idx >= length)
{
return(r);
}
r[idx++] = tmp[3];
}
return(r);
}
/// <summary>
/// Checks for CPU compatibility with the RDRAND instruction. The RDRAND instruction
/// is only available on Intel IvyBridge and higher CPUs.
/// </summary>
/// <returns>true if CPU is compatible with RDRAND</returns>
public static bool GeneratorAvailable()
{
return(RdRandLib.GeneratorAvailable());
}