I'm working on a university project, where I have Tomcat as a web server, and I want to create a multi user environment on top of linux, so every user that logs into my website has his own credentials, and he can access only his own data (files and folders...).

The main issue is that the purpose of the website is executing code on the server-side, so I must have a good (reasonable) protection against malicious code. (a user destroying his own user is fine by me)

I thought that defining a linux-user for every website-user is the best solution - it isolates each user from the other, and I can define each one's permissions.

Can I create users in linux using shell commands? Can I configure max quota/memory/cpu for a user?

Anyone has another idea for managing that kind of multi-user environment?