In the Usenet newsgroup comp.os.linux.questions, in article
Post by Luan PhamHow do yiu suing kppp as normal users without go to root.
Actually, I'm not using kppp - I use a boot script that runs pppd
in 'demand' mode - hence there is no need for the bloated security hole.
However, you can do this several ways:
1. See if your distribution has a usrctrl (User Control) mode. This would
be listed in the configuration file for kppp, probably somewhere in /etc/,
possibly '/etc/kppp.allow'
2. Use 'sudo' in place of 'su'
3. Change the permissions of the real kppp binary (probably in /usr/sbin,
but may be anywhere) to '-rwsr-xr-x' if anyone is allowed to run it. IF
only selected users can do so, put those users in a group such as 'pppusers'
(see the man page for your admin tool to see how to do this - it involves
editing /etc/group which is a bit dangerous to do directly), then change
the ownership of the kppp binary to root:pppusers using the 'chown' command
and change the permissions to -rwsr-x---.
Note that some distributions have a security "feature" that resets the
permissions on SUID binaries to what it defines as "safe". Thus, option 3
above may not work for you.
Old guy