diff --git a/build/VStudio/winfsp.net.csproj b/build/VStudio/winfsp.net.csproj
index 56191c9d..695a13e0 100644
--- a/build/VStudio/winfsp.net.csproj
+++ b/build/VStudio/winfsp.net.csproj
@@ -24,6 +24,7 @@
     <DefineConstants>DEBUG;TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
     <DebugType>pdbonly</DebugType>
@@ -34,6 +35,7 @@
     <DefineConstants>TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
@@ -42,6 +44,9 @@
     <Compile Include="..\..\src\dotnet\FileSystem.cs">
       <Link>FileSystem.cs</Link>
     </Compile>
+    <Compile Include="..\..\src\dotnet\Interop.cs">
+      <Link>Interop.cs</Link>
+    </Compile>
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
diff --git a/src/dotnet/FileSystem.cs b/src/dotnet/FileSystem.cs
index d5b2da8f..1f7131bc 100644
--- a/src/dotnet/FileSystem.cs
+++ b/src/dotnet/FileSystem.cs
@@ -15,10 +15,11 @@
  * software.
  */
 
-namespace Fsp {
-
-public class FileSystem
+namespace Fsp
 {
-}
+
+    public class FileSystem
+    {
+    }
 
 }
diff --git a/src/dotnet/Interop.cs b/src/dotnet/Interop.cs
new file mode 100644
index 00000000..7fa52050
--- /dev/null
+++ b/src/dotnet/Interop.cs
@@ -0,0 +1,324 @@
+/**
+ * @file dotnet/Interop.cs
+ *
+ * @copyright 2015-2017 Bill Zissimopoulos
+ */
+/*
+ * This file is part of WinFsp.
+ *
+ * You can redistribute it and/or modify it under the terms of the GNU
+ * General Public License version 3 as published by the Free Software
+ * Foundation.
+ *
+ * Licensees holding a valid commercial license may use this file in
+ * accordance with the commercial license agreement provided with the
+ * software.
+ */
+
+using System;
+using System.Runtime.InteropServices;
+using System.Security;
+
+namespace Fsp.Interop
+{
+
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct VolumeParams
+    {
+        internal UInt16 Version;
+        internal UInt16 SectorSize;
+        internal UInt16 SectorsPerAllocationUnit;
+        internal UInt16 MaxComponentLength;
+        internal UInt64 VolumeCreationTime;
+        internal UInt32 VolumeSerialNumber;
+        internal UInt32 TransactTimeout;
+        internal UInt32 IrpTimeout;
+        internal UInt32 IrpCapacity;
+        internal UInt32 FileInfoTimeout;
+        internal UInt32 Flags;
+        internal unsafe fixed UInt16 Prefix[192];
+        internal unsafe fixed UInt16 FileSystemName[16];
+
+        internal const UInt32 CaseSensitiveSearch = 0x00000001;
+        internal const UInt32 CasePreservedNames = 0x00000002;
+        internal const UInt32 UnicodeOnDisk = 0x00000004;
+        internal const UInt32 PersistentAcls = 0x00000008;
+        internal const UInt32 ReparsePoints = 0x00000010;
+        internal const UInt32 ReparsePointsAccessCheck = 0x00000020;
+        internal const UInt32 NamedStreams = 0x00000040;
+        internal const UInt32 HardLinks = 0x00000080;
+        internal const UInt32 ExtendedAttributes = 0x00000100;
+        internal const UInt32 ReadOnlyVolume = 0x00000200;
+        internal const UInt32 PostCleanupWhenModifiedOnly = 0x00000400;
+        internal const UInt32 PassQueryDirectoryPattern = 0x00000800;
+        internal const UInt32 AlwaysUseDoubleBuffering = 0x00001000;
+        internal const UInt32 UmFileContextIsUserContext2 = 0x00010000;
+        internal const UInt32 UmFileContextIsFullContext = 0x00020000;
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct VolumeInfo
+    {
+        internal UInt64 TotalSize;
+        internal UInt64 FreeSize;
+        internal UInt16 VolumeLabelLength;
+        internal unsafe fixed UInt16 VolumeLabel[32];
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct FileInfo
+    {
+        internal UInt32 FileAttributes;
+        internal UInt32 ReparseTag;
+        internal UInt64 AllocationSize;
+        internal UInt64 FileSize;
+        internal UInt64 CreationTime;
+        internal UInt64 LastAccessTime;
+        internal UInt64 LastWriteTime;
+        internal UInt64 ChangeTime;
+        internal UInt64 IndexNumber;
+        internal UInt32 HardLinks;
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct OpenFileInfo
+    {
+        internal FileInfo FileInfo;
+        [MarshalAs(UnmanagedType.LPWStr)]
+        internal String NormalizedName;
+        internal UInt16 NormalizedNameSize;
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct DirInfo
+    {
+        internal UInt16 Size;
+        internal FileInfo FileInfo;
+        internal unsafe fixed Byte Padding[24];
+        //internal unsafe fixed UInt16 FileNameBuf[];
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct IoStatusBlock
+    {
+        internal IntPtr Status;
+        internal IntPtr Information;
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct FileSystemInterface
+    {
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 GetVolumeInfo(
+            IntPtr FileSystem,
+            out VolumeInfo VolumeInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 SetVolumeLabel(
+            IntPtr FileSystem,
+            [MarshalAs(UnmanagedType.LPWStr)] String VolumeLabel,
+            out VolumeInfo VolumeInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 GetSecurityByName(
+            IntPtr FileSystem,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            out UInt32 PFileAttributes/* or ReparsePointIndex */,
+            IntPtr SecurityDescriptor,
+            out UIntPtr PSecurityDescriptorSize);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 Create(
+            IntPtr FileSystem,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            UInt32 CreateOptions,
+            UInt32 GrantedAccess,
+            UInt32 FileAttributes,
+            IntPtr SecurityDescriptor,
+            UInt64 AllocationSize,
+            IntPtr PFileContext,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 Open(
+            IntPtr FileSystem,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            UInt32 CreateOptions,
+            UInt32 GrantedAccess,
+            IntPtr PFileContext,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 Overwrite(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            UInt32 FileAttributes,
+            Boolean ReplaceFileAttributes,
+            UInt64 AllocationSize,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate void Cleanup(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            UInt32 Flags);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate void Close(
+            IntPtr FileSystem,
+            IntPtr FileContext);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 Read(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            IntPtr Buffer,
+            UInt64 Offset,
+            UInt32 Length,
+            out UInt32 PBytesTransferred);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 Write(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            IntPtr Buffer,
+            UInt64 Offset,
+            UInt32 Length,
+            Boolean WriteToEndOfFile,
+            Boolean ConstrainedIo,
+            out UInt32 PBytesTransferred,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 Flush(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 GetFileInfo(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 SetBasicInfo(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            UInt32 FileAttributes,
+            UInt64 CreationTime,
+            UInt64 LastAccessTime,
+            UInt64 LastWriteTime,
+            UInt64 ChangeTime,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 SetFileSize(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            UInt64 NewSize,
+            Boolean SetAllocationSize,
+            out FileInfo FileInfo);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 CanDelete(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 Rename(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            [MarshalAs(UnmanagedType.LPWStr)] String NewFileName,
+            Boolean ReplaceIfExists);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 GetSecurity(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            IntPtr SecurityDescriptor,
+            out UIntPtr PSecurityDescriptorSize);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 SetSecurity(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            UInt32 SecurityInformation,
+            IntPtr ModificationDescriptor);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 ReadDirectory(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            [MarshalAs(UnmanagedType.LPWStr)] String Pattern,
+            [MarshalAs(UnmanagedType.LPWStr)] String Marker,
+            IntPtr Buffer,
+            UInt32 Length,
+            out UInt32 PBytesTransferred);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 ResolveReparsePoints(
+            IntPtr FileSystem,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            UInt32 ReparsePointIndex,
+            Boolean ResolveLastPathComponent,
+            out IoStatusBlock PIoStatus,
+            IntPtr Buffer,
+            out UIntPtr PSize);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 GetReparsePoint(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            IntPtr Buffer,
+            out UIntPtr PSize);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 SetReparsePoint(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            IntPtr Buffer,
+            UIntPtr Size);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 DeleteReparsePoint(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            [MarshalAs(UnmanagedType.LPWStr)] String FileName,
+            IntPtr Buffer,
+            UIntPtr Size);
+
+        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+        internal delegate Int32 GetStreamInfo(
+            IntPtr FileSystem,
+            IntPtr FileContext,
+            IntPtr Buffer,
+            UInt32 Length,
+            out UInt32 PBytesTransferred);
+
+        internal unsafe fixed ulong Reserved[40];
+            /* cannot use IntPtr so use ulong */
+    }
+
+    [SuppressUnmanagedCodeSecurity]
+    internal static class Native
+    {
+        internal const String dllname = "winfsp.dll";
+
+        [DllImport(dllname, CallingConvention = CallingConvention.Cdecl)]
+        internal static extern Int32 FspFileSystemCreate(
+            [MarshalAs(UnmanagedType.LPWStr)] String DevicePath,
+            ref VolumeParams VolumeParams,
+            IntPtr Interface,
+            out IntPtr PFileSystem);
+
+        [DllImport(dllname, CallingConvention = CallingConvention.Cdecl)]
+        internal static extern void FspFileSystemDelete(IntPtr FileSystem);
+    }
+
+}