internal static byte[] ProtectData(byte[] data, string name, CryptProtectDataFlags dwFlags)
{
byte[] cipherText = null;
// copy data into unmanaged memory
DPAPI.DATA_BLOB din = new DPAPI.DATA_BLOB();
din.cbData = data.Length;
din.pbData = Marshal.AllocHGlobal(din.cbData);
if (din.pbData.Equals(IntPtr.Zero))
{
throw new OutOfMemoryException("Unable to allocate memory for buffer.");
}
Marshal.Copy(data, 0, din.pbData, din.cbData);
DPAPI.DATA_BLOB dout = new DPAPI.DATA_BLOB();
try
{
bool cryptoRetval = DPAPI.CryptProtectData(ref din, name, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero, dwFlags, ref dout);
if (cryptoRetval)
{
int startIndex = 0;
cipherText = new byte[dout.cbData];
Marshal.Copy(dout.pbData, cipherText, startIndex, dout.cbData);
DPAPI.LocalFree(dout.pbData);
}
else
{
int errCode = Marshal.GetLastWin32Error();
StringBuilder buffer = new StringBuilder(256);
Win32Error.FormatMessage(Win32Error.FormatMessageFlags.FORMAT_MESSAGE_FROM_SYSTEM, IntPtr.Zero, errCode, 0, buffer, buffer.Capacity, IntPtr.Zero);
}
}
finally
{
if (!din.pbData.Equals(IntPtr.Zero))
{
Marshal.FreeHGlobal(din.pbData);
}
}
return(cipherText);
}
