Running root commands as user
 

After a few hours work I have managed to set up pptd so that my daughter can log into her account at Imperial College.

My problem now is that I need to have a script that she can run if she wants to log in. She will have to invoke a couple of root commands and I do not want to give her the root password

What she needs to do to set up networking is:

How can I enable things so that she can run this script as user?

If you add the following line to /etc/sudoers,
then user 'daughter' will be permitted to execute "sudo /usr/sbin/pppd call imperial dump debug logfd 2 nodetach require-mppe" and "sudo /sbin/ip route add default dev ppp0" without supplying a password (if the parameters are changed at all, then the command won't run).

You will probably wish to incorporate those commands in a script, but that script can be run by your daughter and the calls to those two commands will get executed without password prompting.

Use 'man sudoers' for information on additional options.

Do I really have to use visudo to edit this rather than kdesu kate?

No, you do not have to use 'visudo'; however, there are a couple of advantages.

As explained in "man 8 visudo":

So I have this in sudoers

but when I run the script I get

Does your script have a 'sudo' in front of the command?

sudo /usr/sbin/pppd call imperial dump debug logfd 2 nodetach require-mppe

I think I have solved that with chmod +s /usr/sbin/pppd

Oops! Ok added sudo

but now I have this -

Do I need to add pptp to sudoers?

ln -s /usr/sbin/pptp /usr/bin/pptp

seems to solve that. Nearly there

One more problem;

in one script doesn't seem to work

If I separate them into one command in each of two scripts it is OK.

How do I get them to work togrther in one script?

solved that

No you didn't and you shouldn't. If the application isn't meant to be run setuid root then basically you've created a weakness. Sudo is there to avoid making mistakes like that. But what's more worrying is the idea that making anything setuid root "solves" things: I suggest you reread the most basic GNU/Linux docs again.

Yes I had realised that. The problem was that I had left sudo out of the script and I had reset it to -s when the penny dropped.