Store user privileges - the smart way

Question

I'm doing an app that should be for multi-user. currently I have a file that stores username + md5 password hash (with username as salt)

Now I app should be enhanced so that different user can have different privileges. How would you store them the smart way so that nobody can change them but that it's still good to handle for me?

I'm using C#

Answer 1

You seem to be a beginner. For you I may recommend looking at the ASP.NET Membership provider.

But as a side note, please never use MD5. It's not required, and is broken, so it's best to avoid having to justify a reason to using it when there are other perfectly acceptable non-broken hashes.

Answer 2

I think it's better to use database engine to mange this operation(the easiest way), however if you don't prefer to use database, you can use the same file and add keys to make the privileges like the following:

wael rwx

ahmad rw

K x

from those lines you can see that wael have read, write, execute permissions now in your application you will read the permission and allow/disallow the use.