Protecting assembly from hacker

Question

I have a console application references assembly A. I want to ensure that the application will not run if A.dll is tampered or replaced.

One option is to use strong-name signing. But do I need to worry about strong name bypass?

Are there any other good options?

Answer 1

If you can build the protection, a hacker can break it. Don't worry too much about preventing tampering, the guys who can break it in a heartbeat probably won't care, and even if they did, almost nothing you could do would deter them.

The best advice would be to license a product that's built by a team specifically for the purpose of protecting your applications in this way. Just like with cryptography, it's usually best not to roll your own.

Answer 2

You can use an MD5 hash of your dll, but even that's not terribly foolproof because anyone who wants to break your app will just use a reflector and find out what you're really doing and probably just modify your program straight-up. You can get code obfuscators that will help with that, but nothing is perfectly hack-proof. It's really a trade off - what is your value of preventing someone from changing your dll? What is the likelihood that someone will? and how much will it cost you in terms of time = money to protect against that?