Obfuscate WCF Proxy Classes

Question

How to obfuscate WCF proxy classes using Dotfuscator ? I have downloaded Dotfuscator Pro Edition Trial from their website. I obfuscated my app.exe file ,everything was nicely obfuscated but WCF proxy classes were not. (I ILDASMed the exe).

The WCF Proxy classes are giving away structure of my application.Is there any setting I am missing in Dotfuscator application?

Is there a better way to hide WCF service proxy classes?

Answer 1

One way or another, WCF must be able to bind elements in your service's data contract to your client's proxy classes. There is usually little value is obfuscating the proxy classes and their members, but if you do want to obfuscate them you can explicitly set the name of the types and their members using the Name parameter of the [DataContract] or [DataMember] attributes (eg. [DataMember Name="ID"]). Once you've done this, you can disable the "Types and fields marked as serializable" built-in rule from the Rename -> Built-In Rules tab and ensure that "Compatibility with XML serializer" is checked in the Rename -> Options tab. The caveat to this approach is that the names of the serialized properties are still included in your code (in the attributes), and are still sent over the wire.

If you require more protection and you have control of both the service and the client, a better but more cumbersome option might be to put your service contract in its own assembly and process that with Dotfuscator. Again, disable the "Types and fields marked as serializable" built-in rule from the Rename -> Built-In Rules tab and ensure that "Compatibility with XML serializer" is checked in the Rename -> Options tab. Now reference the resulting service contract DLL from both your service and your client application. The tradeoff with this approach is that the contract members will all have obfuscated names (eg. "a") and you will have to reference them as such in your service and client application code. You can examine the map file Dotfuscator produces in order to make sense of the renamed names.