PAM_KSU(8) BSD System Manager's Manual PAM_KSU(8)NAME
pam_ksu — Kerberos 5 SU PAM module
SYNOPSIS
[service-name] module-type control-flag pam_ksu [options]
DESCRIPTION
The Kerberos 5 SU authentication service module for PAM, pam_ksu for only
one PAM category: authentication. In terms of the module-type parameter,
this is the “auth” feature. The module is specifically designed to be
used with the su(1) utility.
Kerberos 5 SU Authentication Module
The Kerberos 5 SU authentication component provides functions to verify
the identity of a user (pam_sm_authenticate()), and determine whether or
not the user is authorized to obtain the privileges of the target
account. If the target account is “root”, then the Kerberos 5 principal
used for authentication and authorization will be the “root” instance of
the current user, e.g. “user/root@REAL.M”. Otherwise, the principal will
simply be the current user's default principal, e.g. “user@REAL.M”.
The user is prompted for a password if necessary. Authorization is per‐
formed by comparing the Kerberos 5 principal with those listed in the
.k5login file in the target account's home directory (e.g. /root/.k5login
for root).
The following options may be passed to the authentication module:
debug syslog(3) debugging information at LOG_DEBUG level.
use_first_pass If the authentication module is not the first in the
stack, and a previous module obtained the user's pass‐
word, that password is used to authenticate the user. If
this fails, the authentication module returns failure
without prompting the user for a password. This option
has no effect if the authentication module is the first
in the stack, or if no previous modules obtained the
user's password.
try_first_pass This option is similar to the use_first_pass option,
except that if the previously obtained password fails,
the user is prompted for another password.
SEE ALSOsu(1), syslog(3), pam.conf(5), pam(8)BSD May 15, 2002 BSD
