On 16/3/23 06:31, Aymeric Agon-Rambosson wrote:
I have a solution to my problem.
For reference, I am putting it here :
A simple way to restrict login based on uids is to modify the file as
such :
#%PAM-1.0
auth required pam_succeed_if.so uid > 500 quiet
@include common-auth
@include common-account
@include common-session
It is possible for dovecot sasl component to use different authorisation
back-ends, such as LDAP, GSSAPI, MySQL etc. These do not necessarily
have the ability to reject uid < 500.
However, generally, these backends can be used by pam as well. In
default debian installations:
cat dovecot
#%PAM-1.0
#auth required pam_faillock.so preauth silent audit
#auth [default=die] pam_faillock.so authfail audit
@include common-auth
@include common-account
@include common-session
cat common-auth
#
# /etc/pam.d/common-auth - authentication settings common to all services
#
# This file is included from other service-specific PAM config files,
# and should contain a list of the authentication modules that define
# the central authentication scheme for use on the system
# (e.g., /etc/shadow, LDAP, Kerberos, etc.). The default is to use the
# traditional Unix authentication mechanisms.
A good practice would be to use postfix --> dovecot/sasl --> pam -->
backend server and do the uid vetting in the dovecot pam configuration
--
Jeremy
