Su problem

["Jakub Fedyczak" <bukaj iep pz zgora pl>]

I'm new to PAM and I have following problem:

I want to allow su only to users listed in /etc/suusers

My /etc/pam.d/su file looks like this:

auth       required     /lib/security/pam_pwdb.so shadow nullok
account    required     /lib/security/pam_pwdb.so
password   required     /lib/security/pam_cracklib.so
password   required     /lib/security/pam_pwdb.so shadow use_authtok nullok
session    required     /lib/security/pam_pwdb.so

I'm adding a line :

auth       requisite    /lib/security/pam_listfile.so item=user sense=allow
file=/etc/suusers onerr=fail

in front of /etc/pam.d/su file and making /etc/suusers owned by root and
with permissions 600. After that nothing happens. Anyone can su to root
account just like before. Please help ! I'm using RedHat 5.2.

Jakub Fedyczak