path: root/modules/pam_nologin/pam_nologin.8

.\"     Title: pam_nologin
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets v1.74.0 <http://docbook.sf.net/>
.\"      Date: 03/02/2009
.\"    Manual: Linux-PAM Manual
.\"    Source: Linux-PAM Manual
.\"  Language: English
.\"
.TH "PAM_NOLOGIN" "8" "03/02/2009" "Linux-PAM Manual" "Linux\-PAM Manual"
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.SH "Name"
pam_nologin \- Prevent non\-root users from login
.SH "Synopsis"
.fam C
.HP \w'\fBpam_nologin\&.so\fR\ 'u
\fBpam_nologin\&.so\fR [file=\fI/path/nologin\fR] [successok]
.fam
.SH "DESCRIPTION"
.PP
pam_nologin is a PAM module that prevents users from logging into the system when
\FC/etc/nologin\F[]
exists\&. The contents of the
\FC/etc/nologin\F[]
file are displayed to the user\&. The pam_nologin module has no effect on the root user\'s ability to log in\&.
.SH "OPTIONS"
.PP
\fBfile=\fR\fB\fI/path/nologin\fR\fR
.RS 4
Use this file instead the default
\FC/etc/nologin\F[]\&.
.RE
.PP
\fBsuccessok\fR
.RS 4
Return PAM_SUCCESS if no file exists, the default is PAM_IGNORE\&.
.RE
.SH "MODULE TYPES PROVIDED"
.PP
The
\fBauth\fR
and
\fBacct\fR
module types are provided\&.
.SH "RETURN VALUES"
.PP
PAM_AUTH_ERR
.RS 4
The user is not root and
\FC/etc/nologin\F[]
exists, so the user is not permitted to log in\&.
.RE
.PP
PAM_BUF_ERR
.RS 4
Memory buffer error\&.
.RE
.PP
PAM_IGNORE
.RS 4
This is the default return value\&.
.RE
.PP
PAM_SUCCESS
.RS 4
Success: either the user is root or the
\FC/etc/nologin\F[]
file does not exist\&.
.RE
.PP
PAM_USER_UNKNOWN
.RS 4
User not known to the underlying authentication module\&.
.RE
.SH "EXAMPLES"
.PP
The suggested usage for
\FC/etc/pam\&.d/login\F[]
is:
.sp
.if n \{\
.RS 4
.\}
.fam C
.ps -1
.nf
.if t \{\
.sp -1
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.BB lightgray adjust-for-leading-newline
.sp -1

auth  required  pam_nologin\&.so
      
.EB lightgray adjust-for-leading-newline
.if t \{\
.sp 1
.\}
.fi
.fam
.ps +1
.if n \{\
.RE
.\}
.sp
.SH "NOTES"
.PP
In order to make this module effective, all login methods should be secured by it\&. It should be used as a
\fIrequired\fR
method listed before any
\fIsufficient\fR
methods in order to get standard Unix nologin semantics\&. Note, the use of
\fBsuccessok\fR
module argument causes the module to return
\fIPAM_SUCCESS\fR
and as such would break such a configuration \- failing
\fIsufficient\fR
modules would lead to a successful login because the nologin module
\fIsucceeded\fR\&.
.SH "SEE ALSO"
.PP

\fBnologin\fR(5),
\fBpam.conf\fR(5),
\fBpam.d\fR(5),
\fBpam\fR(8)
.SH "AUTHOR"
.PP
pam_nologin was written by Michael K\&. Johnson <johnsonm@redhat\&.com>\&.