Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

external/referencesource/System.ServiceModel/System/ServiceModel/Security/MessageProtectionOrder.cs

@@ -0,0 +1,22 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+//-----------------------------------------------------------------------------
+namespace System.ServiceModel.Security
+{
+    public enum MessageProtectionOrder
+    {
+        SignBeforeEncrypt,
+        SignBeforeEncryptAndEncryptSignature,
+        EncryptBeforeSign,
+    }
+
+    static class MessageProtectionOrderHelper
+    {
+        internal static bool IsDefined(MessageProtectionOrder value)
+        {
+            return value == MessageProtectionOrder.SignBeforeEncrypt
+                || value == MessageProtectionOrder.SignBeforeEncryptAndEncryptSignature
+                || value == MessageProtectionOrder.EncryptBeforeSign;
+        }
+    }
+}