private static byte[] CreateHmacForSecureString(IntPtr hProv, IntPtr hKey, SecureString ss)
{
IntPtr hHash = IntPtr.Zero;
CryptCreateHash(hProv, CALG_HMAC, hKey, 0, ref hHash);
var hmacInfo = new _HMAC_Info()
{
HashAlgid = CALG_SHA512
};
CryptSetHashParam(hHash, HP_HMAC_INFO, ref hmacInfo, 0);
var bstr = Marshal.SecureStringToBSTR(ss);
var len = (uint)Marshal.ReadInt32(bstr, -4);
CryptHashData(hHash, bstr, len, 0);
Marshal.ZeroFreeBSTR(bstr);
uint length = 64;
byte[] pbData = new byte[64];
CryptGetHashParam(hHash, HP_HASHVAL, pbData, ref length, 0);
CryptDestroyHash(hHash);
return(pbData);
}
static extern bool CryptSetHashParam(IntPtr hHash, uint dwParam, ref _HMAC_Info pbData, Int32 dwFlags);
