PAM_NOLOGIN - Online Linux Manual Page

Section : 8
Updated : 09/03/2021
Source : Linux-PAM Manual
Note : Linux−PAM Manual

NAME

pam_nologin − Prevent non−root users from login

SYNOPSIS

pam_nologin.so

[file=

/path/nologin

]

[successok]

DESCRIPTION

pam_nologin is a PAM module that prevents users from logging into the system when /var/run/nologin or /etc/nologin exists. The contents of the file are displayed to the user. The pam_nologin module has no effect on the root user's ability to log in.

OPTIONS

file=

/path/nologin

Use this file instead the default /var/run/nologin or /etc/nologin.

successok

Return PAM_SUCCESS if no file exists, the default is PAM_IGNORE.

MODULE TYPES PROVIDED

The auth

and

account

module types are provided.

RETURN VALUES

PAM_AUTH_ERR

The user is not root and /etc/nologin exists, so the user is not permitted to log in.

PAM_BUF_ERR

Memory buffer error.

PAM_IGNORE

This is the default return value.

PAM_SUCCESS

Success: either the user is root or the nologin file does not exist.

PAM_USER_UNKNOWN

User not known to the underlying authentication module.

EXAMPLES

The suggested usage for /etc/pam.d/login is:

auth required pam_nologin.so

NOTES

In order to make this module effective, all login methods should be secured by it. It should be used as a required

method listed before any

sufficient

methods in order to get standard Unix nologin semantics. Note, the use of

successok

module argument causes the module to return

PAM_SUCCESS

and as such would break such a configuration − failing

sufficient

modules would lead to a successful login because the nologin module

succeeded