Protect .NET code from reverse engineering?

Question

Obfuscation is one way, but it can\'t protect from breaking the piracy protection security of the application. How do I make sure that the application is not tampered with,

Answer 1

If you want people to able to run your code (and if you don't, then why did you write it in the first place?), then their CPU needs to be able to execute your code. In order to be able to execute the code, the CPU needs to be able to understand it.

Since CPUs are dumb, and humans aren't, this means that humans can understand the code as well.

There's only one way to make sure that your users don't get your code: don't give them your code.

This can be achieved two ways: Software as a service (SaaS), that is, you run your software on your server and only let your users access it remotely. This is the model that Stack Overflow uses, for example. I'm pretty sure that Stack Overflow doesn't obfuscate their code, yet you can't decompile it.

The other way is the appliance model: instead of giving your users your code, you give them a computer containing the code. This is the model that gaming consoles, most mobile phones and TiVo use. Note that this only works if you "own" the entire execution path: you need to build your own CPU, your own computer, write your own operating system and your own CLI implementation. Then, and only then can you protect your code. (But note that even the tiniest mistake will render all of your protections useless. Microsoft, Apple, Sony, the music industry and the movie industry can attest to that.)

Or, you could just do nothing, which means that your code will be automatically protected by copyright law.