1 files changed, 45 insertions, 0 deletions
diff --git a/src/mscorlib/corefx/Interop/Windows/kernel32/Interop.SafeCreateFile.cs b/src/mscorlib/corefx/Interop/Windows/kernel32/Interop.SafeCreateFile.cs
new file mode 100644
index 0000000000..4192f569e0
--- /dev/null
+++ b/src/mscorlib/corefx/Interop/Windows/kernel32/Interop.SafeCreateFile.cs
@@ -0,0 +1,45 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.IO;
+using System.Runtime.InteropServices;
+using Microsoft.Win32.SafeHandles;
+
+internal partial class Interop
+{
+    internal partial class Kernel32
+    {
+        internal static readonly IntPtr INVALID_HANDLE_VALUE = new IntPtr(-1);  // WinBase.h
+
+        /// <summary>
+        /// Does not allow access to non-file devices. This disallows DOS devices like "con:", "com1:",
+        /// "lpt1:", etc.  Use this to avoid security problems, like allowing a web client asking a server
+        /// for "http://server/com1.aspx" and then causing a worker process to hang.
+        /// </summary>
+        internal static SafeFileHandle SafeCreateFile(
+            String lpFileName,
+            int dwDesiredAccess,
+            System.IO.FileShare dwShareMode,
+            ref Interop.Kernel32.SECURITY_ATTRIBUTES securityAttrs,
+            FileMode dwCreationDisposition,
+            int dwFlagsAndAttributes,
+            IntPtr hTemplateFile)
+        {
+            SafeFileHandle handle = UnsafeCreateFile(lpFileName, dwDesiredAccess, dwShareMode, ref securityAttrs, dwCreationDisposition, dwFlagsAndAttributes, hTemplateFile);
+
+            if (!handle.IsInvalid)
+            {
+                int fileType = Interop.Kernel32.GetFileType(handle);
+                if (fileType != Interop.Kernel32.FileTypes.FILE_TYPE_DISK)
+                {
+                    handle.Dispose();
+                    throw new NotSupportedException(SR.NotSupported_FileStreamOnNonFiles);
+                }
+            }
+
+            return handle;
+        }
+    }
+}