.\" Copyright (c) 2001 Mark R V Murray
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.\" $FreeBSD$
.\"
.Dd July 8, 2001
.Dt PAM_WHEEL 8
.Os
.Sh NAME
.Nm pam_wheel
.Nd Wheel PAM module
.Sh SYNOPSIS
.Op Ar service-name
.Ar module-type
.Ar control-flag
.Pa pam_wheel
.Op Ar options
.Sh DESCRIPTION
The Wheel authentication service module for PAM,
.Nm
provides functionality for only one PAM category:
authentication.
In terms of the
.Ar module-type
parameter, this is the
.Dq Li auth
feature.
It also provides a null function for session management.
.Ss Wheel Authentication Module
The Wheel authentication component
.Pq Fn pam_sm_authenticate ,
permit authentication to members of a group,
which defaults to
.Dq Li wheel .
.Pp
The following options may be passed to the authentication module:
.Bl -tag -width ".Cm exempt_if_empty"
.It Cm debug
.Xr syslog 3
debugging information at
.Dv LOG_DEBUG
level.
.It Cm no_warn
suppress warning messages to the user.
These messages include
reasons why the user's
authentication attempt was declined.
.It Cm auth_as_self
check for
.Dq Li wheel
membership against
the current login name
(given by
.Xr getlogin 2 ) .
.It Cm trust
return
.Dv PAM_SUCCESS
instead of
.Dv PAM_IGNORE
if the user is a member of the group (default is
.Dq Li wheel ) .
.It Cm deny
invert the operation
if the user is a member of the
(default
.Dq Li wheel )
group.
Returns failure instead of success.
Mainly of use with the
.Cm group Ns = Ns Ar foo
option.
.It Cm group Ns = Ns Ar foo
checking for membership of group
.Ar foo
instead of the default group
.Dq Li wheel .
.It Cm noroot_ok
return
.Dv PAM_SUCCESS
instead of
.Dv PAM_IGNORE
if the user is authenticating
to a user
that is not the superuser.
.It Cm exempt_if_empty
return
.Dv PAM_IGNORE
if the specified group (default group of
.Dq Li wheel )
is empty, providing traditional
.Bx
.Xr su 8
semantics permitting any user to
.Dq su
if the wheel group is empty.
.El
.Sh SEE ALSO
.Xr getlogin 2 ,
.Xr syslog 3 ,
.Xr group 5 ,
.Xr pam.conf 5 ,
.Xr pam 8