Changed how internal structures are created for handling SecureBuffers.

SecureBuffer/SecureBufferDesc.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Runtime.ConstrainedExecution;
 using System.Runtime.InteropServices;
 using System.Text;
 using System.Threading.Tasks;
@@ -8,7 +9,7 @@ using System.Threading.Tasks;
 namespace NSspi.Contexts
 {
     [StructLayout( LayoutKind.Sequential)]
-    public unsafe struct SecureBufferDesc
+    public struct SecureBufferDescInternal
     {
         public int Version;
         public int NumBuffers;
@@ -18,6 +19,4 @@ namespace NSspi.Contexts
 
         public const int ApiVersion = 0;
     }
-
-
 }