Hello, I'm working on a project for a client in which the client owns the source code that I develop. I plan on purchasing and using a 3rd party .NET library in this project. When I purchase the library, I have the right to use it royalty free on as many sites as I like. However, the library uses a license key that must be set in a property before using the library.
What would be the best way to "hide" this license key from the client?
Thank you in advance for any suggestions!
Whatever you do here, the assemblies will always end up being decompilable, so there's always scope for the license key being rooted out. Given this, I don't think it's worth throwing a lot of effort at hiding the license key - perhaps a simple base-64 encode or XOR based 'encryption' (loose sense of the term) would suffice? Running an obfuscator over the assembly that contains the license key might help muddy the waters for a would-be scavenger.
It depends completely on the library and where the key should be set.
I suggest contacting the library vendors directly.
Would storing the license as an embedded resourse help out here? If it's a case of you don't want to store it in the webconfig? will the client get to see your sourse code? That or encrypting or obfuscation as mentioned by Will A are the ways to go.