'\" t
.\"     Title: login.access
.\"    Author: Marek Michałkiewicz
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 11/08/2022
.\"    Manual: File Formats and Configuration Files
.\"    Source: shadow-utils 4.13
.\"  Language: English
.\"
.TH "LOGIN\&.ACCESS" "5" "11/08/2022" "shadow\-utils 4\&.13" "File Formats and Configuration"
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.SH "NAME"
login.access \- login access control table
.SH "DESCRIPTION"
.PP
The
\fIlogin\&.access\fR
file specifies (user, host) combinations and/or (user, tty) combinations for which a login will be either accepted or refused\&.
.PP
When someone logs in, the
\fIlogin\&.access\fR
is scanned for the first entry that matches the (user, host) combination, or, in case of non\-networked logins, the first entry that matches the (user, tty) combination\&. The permissions field of that table entry determines whether the login will be accepted or refused\&.
.PP
Each line of the login access control table has three fields separated by a ":" character:
.PP
\fIpermission\fR:\fIusers\fR:\fIorigins\fR
.PP
The first field should be a "\fI+\fR" (access granted) or "\fI\-\fR" (access denied) character\&. The second field should be a list of one or more login names, group names, or
\fIALL\fR
(always matches)\&. The third field should be a list of one or more tty names (for non\-networked logins), host names, domain names (begin with "\&."), host addresses, internet network numbers (end with "\&."),
\fIALL\fR
(always matches) or
\fILOCAL\fR
(matches any string that does not contain a "\&." character)\&. If you run NIS you can use @netgroupname in host or user patterns\&.
.PP
The
\fIEXCEPT\fR
operator makes it possible to write very compact rules\&.
.PP
The group file is searched only when a name does not match that of the logged\-in user\&. Only groups are matched in which users are explicitly listed: the program does not look at a user\*(Aqs primary group id value\&.
.SH "FILES"
.PP
/etc/login\&.defs
.RS 4
Shadow password suite configuration\&.
.RE
.SH "SEE ALSO"
.PP
\fBlogin\fR(1)\&.