<?xml version='1.0'?> <!--*-nxml-*--> <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> <!-- This file is part of systemd. Copyright 2010 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. --> <refentry id="pam_systemd" conditional='HAVE_PAM'> <refentryinfo> <title>pam_systemd</title> <productname>systemd</productname> <authorgroup> <author> <contrib>Developer</contrib> <firstname>Lennart</firstname> <surname>Poettering</surname> <email>lennart@poettering.net</email> </author> </authorgroup> </refentryinfo> <refmeta> <refentrytitle>pam_systemd</refentrytitle> <manvolnum>8</manvolnum> </refmeta> <refnamediv> <refname>pam_systemd</refname> <refpurpose>Register user sessions in the systemd login manager</refpurpose> </refnamediv> <refsynopsisdiv> <para><filename>pam_systemd.so</filename></para> </refsynopsisdiv> <refsect1> <title>Description</title> <para><command>pam_systemd</command> registers user sessions with the systemd login manager <citerefentry><refentrytitle>systemd-logind.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, and hence the systemd control group hierarchy.</para> <para>On login, this module ensures the following:</para> <orderedlist> <listitem><para>If it does not exist yet, the user runtime directory <filename>/run/user/$USER</filename> is created and its ownership changed to the user that is logging in.</para></listitem> <listitem><para>The <varname>$XDG_SESSION_ID</varname> environment variable is initialized. If auditing is available and <command>pam_loginuid.so</command> run before this module (which is highly recommended), the variable is initialized from the auditing session id (<filename>/proc/self/sessionid</filename>). Otherwise an independent session counter is used.</para></listitem> <listitem><para>A new systemd scope unit is created for the session. If this is the first concurrent session of the user, an implicit slice below <filename>user.slice</filename> is automatically created and the scope placed in it. In instance of the system service <filename>user@.service</filename> which runs the systemd user manager instance.</para></listitem> </orderedlist> <para>On logout, this module ensures the following:</para> <orderedlist> <listitem><para>If this is enabled, all processes of the session are terminated. If the last concurrent session of a user ends, his user systemd instance will be terminated too, and so will the user's slice unit.</para></listitem> <listitem><para>If the last concurrent session of a user ends, the <varname>$XDG_RUNTIME_DIR</varname> directory and all its contents are removed, too.</para></listitem> </orderedlist> <para>If the system was not booted up with systemd as init system, this module does nothing and immediately returns PAM_SUCCESS.</para> </refsect1> <refsect1> <title>Options</title> <para>The following options are understood:</para> <variablelist class='pam-directives'> <varlistentry> <term><option>class=</option></term> <listitem><para>Takes a string argument which sets the session class. The XDG_SESSION_CLASS environmental variable takes precedence.</para></listitem> </varlistentry> <varlistentry> <term><option>debug=</option></term> <listitem><para>Takes a boolean argument. If yes, the module will log debugging information as it operates.</para></listitem> </varlistentry> </variablelist> </refsect1> <refsect1> <title>Module Types Provided</title> <para>Only <option>session</option> is provided.</para> </refsect1> <refsect1> <title>Environment</title> <para>The following environment variables are set for the processes of the user's session:</para> <variablelist class='environment-variables'> <varlistentry> <term><varname>$XDG_SESSION_ID</varname></term> <listitem><para>A session identifier, suitable to be used in filenames. The string itself should be considered opaque, although often it is just the audit session ID as reported by <filename>/proc/self/sessionid</filename>. Each ID will be assigned only once during machine uptime. It may hence be used to uniquely label files or other resources of this session.</para></listitem> </varlistentry> <varlistentry> <term><varname>$XDG_RUNTIME_DIR</varname></term> <listitem><para>Path to a user-private user-writable directory that is bound to the user login time on the machine. It is automatically created the first time a user logs in and removed on his final logout. If a user logs in twice at the same time, both sessions will see the same <varname>$XDG_RUNTIME_DIR</varname> and the same contents. If a user logs in once, then logs out again, and logs in again, the directory contents will have been lost in between, but applications should not rely on this behavior and must be able to deal with stale files. To store session-private data in this directory, the user should include the value of <varname>$XDG_SESSION_ID</varname> in the filename. This directory shall be used for runtime file system objects such as <constant>AF_UNIX</constant> sockets, FIFOs, PID files and similar. It is guaranteed that this directory is local and offers the greatest possible file system feature set the operating system provides.</para></listitem> </varlistentry> </variablelist> </refsect1> <refsect1> <title>Example</title> <programlisting>#%PAM-1.0 auth required pam_unix.so auth required pam_nologin.so account required pam_unix.so password required pam_unix.so session required pam_unix.so session required pam_loginuid.so session required pam_systemd.so</programlisting> </refsect1> <refsect1> <title>See Also</title> <para> <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd-logind.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>loginctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>pam.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>pam.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>pam_loginuid</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry> </para> </refsect1> </refentry>