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Obfuscation During Build Process

Obfuz automatically performs obfuscation during Unity's build process.

Principle​

Obfuz.Unity.ObfuscationProcess implements the IPostBuildPlayerScriptDLLs interface and performs obfuscation in the callback event.

Settings​

All obfuscation settings are contained in ObfuzSettings. See Configuration for details.

Enable/Disable Obfuscation During Build​

The ObfuzSettings.Enable option indicates whether to perform obfuscation in the build pipeline. If this option is disabled, obfuscation will not be performed during the build process.

This option only affects the build process and does not impact manual obfuscation via the Obfuscator.

Obfuscation Events​

Obfuz provides two obfuscation events:

  • Obfuz.Unity.ObfuscationBeginEventArgs
  • Obfuz.Unity.ObfuscationEndEventArgs

Listen for the obfuscation start event with ObfuscationProcess.OnObfuscationBegin += YourCallback, and the obfuscation end event with ObfuscationProcess.OnObfuscationEnd += YourCallback.

In practice, it's recommended to use the [InitializeOnLoadMethod] attribute to listen for obfuscation events immediately after assemblies are loaded. Example code:

public class TestObfuscationEvent
{
    [InitializeOnLoadMethod]
    private static void Init()
    {
        ObfuscationProcess.OnObfuscationBegin += OnObfuscationBegin;
        ObfuscationProcess.OnObfuscationEnd += OnObfuscationEnd;
    }

    private static void OnObfuscationBegin(ObfuscationBeginEventArgs args)
    {
        Debug.Log($"OnObfuscationBegin");
    }

    private static void OnObfuscationEnd(ObfuscationEndEventArgs args)
    {
        Debug.Log($"OnObfuscationEnd");
    }
}

Accessing Original and Obfuscated Assemblies​

The obfuscation process modifies all assemblies in the AssemblySettings.AssembliesToObfuscate and AssemblySettings.NonObfuscatedButReferenceingObfuscatedAssemblies lists.

  • Before obfuscation, original assemblies are copied to Library/Obfuz/{buildTarget}/OriginalAssemblies.
  • After obfuscation, modified assemblies are copied to Library/Obfuz/{buildTarget}/ObfuscatedAssemblies.

link.xml Issues​

If you obfuscate AOT assemblies and preserve types from these obfuscated AOT assemblies in link.xml, the preserved names will be the original (pre-obfuscation) names, making these configurations ineffective.

Obfuz solves this problem by scanning all link.xml files during the IUnityLinkerProcessor.GenerateAdditionalLinkXmlFile event, replacing pre-obfuscation names with post-obfuscation names, and generating a new link.xml file. See the Obfuz.Unity.LinkXmlProcess class for implementation details.