I'm developing a commercial project on an ARM based embedded board with a custom Linux kernel on it, using Ruby. Target workspace of the project and the device is a closed-environment, no ethernet, inernet, I/O devices etc... I want to protect my code/program so that; it'll only work on the specific machines I let (so; people cant just copy and paste my code/program on to their embedded boards and run it w/o permission). This can probably done with the machine's MAC address tho; I don't have any experience on the subject. I guess, just a simple if(device.MACAddr == "XX:XX....XX") wouldn't be depandable (not to mention people can just easily delete the check from my code). I can't use some ruby obfuscators, which I found thru google, beacuse; the device doesnt run ruby-external-C-libraries or such stuff, only pure ruby code.
So; what are your suggestions, what type of approach should I take?
This is isomorphic to the problem of DRM. You're giving a person both a lock and the key to that lock, and trying to stop that person from using the key in a way you don't like.
Therefore, I suggest using the same methods that other DRM users do: put your terms in the license, and sue them if they violate it. You need to use the law to enforce the other terms of the license, anyway.