Question

I was thinking about obfuscating a commercial .Net application. But is it really worth the effort to select, buy and use such a tool? Are the obfuscated binaries really safe from reverse engineering?

Answer 1

You may not have to buy a tool – Visual Studio.NET comes with a community version of Dotfuscator. Other free obfuscation tools are listed here, and they may meet your needs.

It’s possible that the obfuscated binaries aren’t safe from reverse engineering, just like it’s possible that your bike lock might be breakable/pickable. However, it’s often the case that a small inconvenience is enough to deter would be code/bicycle thieves.

Also, if ever it comes time to assert your rights to a piece of code in court, having been seen to make an effort to protect it (by obfuscating it) may give you extra points. 🙂

You do have to consider the downsides, though – it can be more difficult to use reflection with obfuscated code, and if you’re using something like log4net to generate parts of log lines based on the name of the class involved, these messages can become much more difficult to interpret.