WPF Licensing : Good C# obfuscators?

Hello,

We currently use .NET Reactor for obfuscation.  Regardless of the obfuscator, you may need to watch the obfuscation level you use to minimize the impact it has on your logic and the possible introduction of issues.  Related to licensing, a main focus is ensuring string encryption is enabled on the obfuscator.

I've been trying to use the trial version of .NET Reactor to obfuscate my Licensee and LicenseKey values, but so far, I haven’t had any success. Reactor itself seems to be working — I can see many of the security layers applied — but the string values for my license information remain unchanged in the resulting assembly.

Since you use .NET Reactor and this is for your product, I thought you’d be the best person to ask for help. I’ve implemented it in my WPF application exactly as shown in your documentation, with both String Encryption and Obfuscation enabled. After running the Protect process (either manually or during build) and inspecting the output in dotPeek, I can see that the assembly code for these strings is completely unmodified.

This is my first time working with obfuscation, so I suspect it’s just a simple configuration issue that I’m overlooking. Any guidance you can provide would be greatly appreciated.

public partial class App : Application
{
    private static readonly string Licencee = "My Licence";
    private static readonly string LicenceKey = "My Licence Key";

    protected override void OnStartup(StartupEventArgs e)
    {
        ActiproSoftware.Products.ActiproLicenseManager.RegisterLicense(Licencee, LicenceKey);

        base.OnStartup(e);
    }
}​

Thanks,

Hi Bob,

When I look at our obfuscated assemblies, I do see strings being replaced with method calls to an internal type that .NET Reactor injects.

Our products' .NET Reactor project settings are pretty basic.  Each project's resulting XML contains these lines related to string encryption settings:

<String_Encryption>true</String_Encryption>
<String_Encryption_Mode>All</String_Encryption_Mode>
<String_Encryption_InclusionExclusion_List />

I'm not sure if string encryption is disabled in the trial version or not.  Do you see other strings getting replaced by a method call?  If so, perhaps try changing how the strings are declared, such as put them directly in a method and see if it helps.

Beyond that, contacting .NET Reactor support is probably your best option since they would know why those strings aren't encrypting.

Thanks for the reply.  I  actually just stumbled onto the answer. Apparently, dotPeek will use a PDB file if present to decompile.  It was there.  Remove it and viola! The correct result is as you described.