.Net Application Reverse Engineering

[laythcullen]

Link:

• Go to the official dnSpy repository on GitHub (https://github.com/dnSpy/dnSpy) and click on the "releases" tab.
• Download the latest stable release suitable for your operating system (Windows, macOS, or Linux).
• Extract the downloaded file and run the dnSpy.exe (Windows) or dnSpy.app (macOS) to install dnSpy.

Step 2: Load the Target Assembly

• Open dnSpy and click on the "Open" button or press Ctrl + O.
• Browse and select the .NET assembly (usually a .exe or .dll file) you want to reverse engineer.
• Wait for dnSpy to load the assembly, which will display the assembly's namespace, classes, and methods in the tree-view on the left side of the application.

Step 3: Inspecting the Assembly

• Expand the tree-view to navigate through the assembly's namespace and classes to analyze the code structure.
• Double-click on a specific class to view its contents, including fields, properties, methods, and more.
• You can review the IL code, decompiled C# code, and even view the original source code if available.

Step 4: Modifying the Assembly

• Right-click on a class, method, or property to access various modification options.
• Select "Edit Method (C#)" to modify the decompiled C# code directly.
• Make the desired changes and save the modified code.
• Alternatively, you can also "Edit IL Instructions" to modify the assembly at a lower level.

Step 5: Debugging the Assembly

• dnSpy also allows for debugging the assembly by setting breakpoints and stepping through the code.
• Right-click on a method and select "Set Breakpoint" to pause execution at a specific line for further analysis.
• Use the debug features like stepping into, over, or out of code to understand its behavior.

Step 6: Saving Changes

• Once you finish analyzing or modifying the assembly, you can save the changes.
• Click on the "Save" button or press Ctrl + S to save the modified assembly.
• Optionally, you can also create a new assembly from the modified code using the "Save Module" or "Save Assembly" option.

That's it! You are now well-equipped to embark on your .NET reverse engineering journey using dnSpy.