Restricting users using the modem

[Stefan Saliba]

Is there a way to restrict users from being allowed to login when dialing from a modem.

i.e. is there a way that only a set of logins will be allowed to login when prompted after dialing in from a modem ?

[Paula J Frazer-Campbell]

Hi
There are several ways to control logins from dialup connections. A dial back system is effective - search the forum for info on this also see man dialups on configuring a dial in password system.

HTH

Paula

[Andreas Voss · Accepted solution]

Hi,

i'm doing this within the /etc/profile:

case `tty` in
*ttyd0p7) grep -qx $LOGNAME /etc/modem.allow
if [ $? != 0 ] ; then
echo "No login allowed !"
exec false
fi
;;
esac

Only user who are listed in /etc/modem.allow are able to login via modem (check your device ttyd....)

Regards

[Rodney Hills]

Two possible controls-
1) Given modem dialin users a secondary password. See man 4 dialups on how you can force an additional password prompt.

2) Assuming users use ksh or sh for their login shell, you can modify /etc/profile to check that the user is allowed to dialin and kick them off if not valid. See /usr/bin/tty will tell you the tty name, and /usr/bin/whoami will tell you the user.