<?xml version='1.0'?> <!--*-nxml-*-->
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
-
-<!--
- SPDX-License-Identifier: LGPL-2.1+
-
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
--->
+<!-- SPDX-License-Identifier: LGPL-2.1+ -->
<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>
<citerefentry><refentrytitle>systemd-logind.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
and hence the systemd control group hierarchy.</para>
+ <para>The module also applies various resource management and runtime parameters to the new session, as
+ configured in the <ulink url="https://systemd.io/USER_RECORD">JSON User Record</ulink> of the user, when
+ one is defined.</para>
+
<para>On login, this module — in conjunction with <filename>systemd-logind.service</filename> — ensures the
following:</para>
<listitem><para>A new systemd scope unit is created for the session. If this is the first concurrent session of
the user, an implicit per-user slice unit below <filename>user.slice</filename> is automatically created and the
scope placed into it. An instance of the system service <filename>user@.service</filename>, which runs the
- systemd user manager instance, is started. </para></listitem>
+ systemd user manager instance, is started.</para></listitem>
+
+ <listitem><para>The <literal>$TZ</literal>, <literal>$EMAIL</literal> and <literal>$LANG</literal>
+ environment variables are configured for the user, based on the respective data from the user's JSON
+ record (if it is defined). Moreover, any environment variables explicitly configured in the user record
+ are imported, and the umask, nice level, and resource limits initialized.</para></listitem>
</orderedlist>
<para>On logout, this module ensures the following:</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. One of
- <literal>user</literal>,
- <literal>greeter</literal>,
- <literal>lock-screen</literal> or
- <literal>background</literal>. See
- <citerefentry><refentrytitle>sd_session_get_class</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- for details about the session class.</para></listitem>
+ <term><varname>class=</varname></term>
+
+ <listitem><para>Takes a string argument which sets the session class. The <varname>XDG_SESSION_CLASS</varname>
+ environment variable (see below) takes precedence. One of <literal>user</literal>, <literal>greeter</literal>,
+ <literal>lock-screen</literal> or <literal>background</literal>. See
+ <citerefentry><refentrytitle>sd_session_get_class</refentrytitle><manvolnum>3</manvolnum></citerefentry> for
+ details about the session class.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>type=</varname></term>
+
+ <listitem><para>Takes a string argument which sets the session type. The <varname>XDG_SESSION_TYPE</varname>
+ environment variable (see below) takes precedence. One of <literal>unspecified</literal>,
+ <literal>tty</literal>, <literal>x11</literal>, <literal>wayland</literal> or <literal>mir</literal>. See
+ <citerefentry><refentrytitle>sd_session_get_type</refentrytitle><manvolnum>3</manvolnum></citerefentry> for
+ details about the session type.</para></listitem>
</varlistentry>
<varlistentry>
- <term><option>type=</option></term>
-
- <listitem><para>Takes a string argument which sets the session
- type. The XDG_SESSION_TYPE environmental variable takes
- precedence. One of
- <literal>unspecified</literal>,
- <literal>tty</literal>,
- <literal>x11</literal>,
- <literal>wayland</literal> or
- <literal>mir</literal>. See
- <citerefentry><refentrytitle>sd_session_get_type</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- for details about the session type.</para></listitem>
+ <term><varname>desktop=</varname></term>
+
+ <listitem><para>Takes a single, short identifier string for the desktop environment. The
+ <varname>XDG_SESSION_DESKTOP</varname> environment variable (see below) takes precedence. This may be used to
+ indicate the session desktop used, where this applies and if this information is available. For example:
+ <literal>GNOME</literal>, or <literal>KDE</literal>. It is recommended to use the same identifiers and
+ capitalization as for <varname>$XDG_CURRENT_DESKTOP</varname>, as defined by the <ulink
+ url="http://standards.freedesktop.org/desktop-entry-spec/latest/">Desktop Entry
+ Specification</ulink>. (However, note that the option only takes a single item, and not a colon-separated list
+ like <varname>$XDG_CURRENT_DESKTOP</varname>.) See
+ <citerefentry><refentrytitle>sd_session_get_desktop</refentrytitle><manvolnum>3</manvolnum></citerefentry> for
+ further details.</para></listitem>
</varlistentry>
<varlistentry>
- <term><option>debug<optional>=</optional></option></term>
+ <term><varname>debug</varname><optional>=</optional></term>
- <listitem><para>Takes an optional
- boolean argument. If yes or without
- the argument, the module will log
- debugging information as it
- operates.</para></listitem>
+ <listitem><para>Takes an optional boolean argument. If yes or without the argument, the module will log
+ debugging information as it operates.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Environment</title>
- <para>The following environment variables are set for the
- processes of the user's session:</para>
+ <para>The following environment variables are initialized by the module and available to the processes of the
+ user's session:</para>
<variablelist class='environment-variables'>
<varlistentry>
<term><varname>$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>
+ <listitem><para>A short 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. Combine this ID with the boot
+ identifier, as returned by
+ <citerefentry><refentrytitle>sd_id128_get_boot</refentrytitle><manvolnum>3</manvolnum></citerefentry>, for a
+ globally unique identifier.</para></listitem>
</varlistentry>
<varlistentry>
is not set if the current user is not the original user of the session.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>$TZ</varname></term>
+ <term><varname>$EMAIL</varname></term>
+ <term><varname>$LANG</varname></term>
+
+ <listitem><para>If a JSON user record is known for the user logging in these variables are
+ initialized from the respective data in the record.</para></listitem>
+ </varlistentry>
+
</variablelist>
- <para>The following environment variables are read by the module
- and may be used by the PAM service to pass metadata to the
- module:</para>
+ <para>The following environment variables are read by the module and may be used by the PAM service to pass
+ metadata to the module. If these variables are not set when the PAM module is invoked but can be determined
+ otherwise they are set by the module, so that these variables are initialized for the session and applications if
+ known at all.</para>
<variablelist class='environment-variables'>
<varlistentry>
<term><varname>$XDG_SESSION_TYPE</varname></term>
- <listitem><para>The session type. This may be used instead of
- <option>session=</option> on the module parameter line, and is
- usually preferred.</para></listitem>
+ <listitem><para>The session type. This may be used instead of <varname>type=</varname> on the module parameter
+ line, and is usually preferred.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>$XDG_SESSION_CLASS</varname></term>
- <listitem><para>The session class. This may be used instead of
- <option>class=</option> on the module parameter line, and is
- usually preferred.</para></listitem>
+ <listitem><para>The session class. This may be used instead of <varname>class=</varname> on the module parameter
+ line, and is usually preferred.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>$XDG_SESSION_DESKTOP</varname></term>
- <listitem><para>A single, short identifier string for the
- desktop environment. This may be used to indicate the session
- desktop used, where this applies and if this information is
- available. For example: <literal>GNOME</literal>, or
- <literal>KDE</literal>. It is recommended to use the same
- identifiers and capitalization as for
- <varname>$XDG_CURRENT_DESKTOP</varname>, as defined by the
- <ulink
- url="http://standards.freedesktop.org/desktop-entry-spec/latest/">Desktop
- Entry Specification</ulink>. (However, note that
- <varname>$XDG_SESSION_DESKTOP</varname> only takes a single
- item, and not a colon-separated list like
- <varname>$XDG_CURRENT_DESKTOP</varname>.) See
- <citerefentry><refentrytitle>sd_session_get_desktop</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- for more details.</para></listitem>
+ <listitem><para>The desktop identifier. This may be used instead of <varname>desktop=</varname> on the module
+ parameter line, and is usually preferred.</para></listitem>
</varlistentry>
<varlistentry>
</varlistentry>
</variablelist>
- <para>If not set, <command>pam_systemd</command> will determine the
- values for <varname>$XDG_SEAT</varname> and <varname>$XDG_VTNR</varname>
- based on the <varname>$DISPLAY</varname> variable.</para>
+ <para>If not set, <command>pam_systemd</command> will initialize
+ <varname>$XDG_SEAT</varname> and <varname>$XDG_VTNR</varname>
+ based on the <varname>$DISPLAY</varname> variable (if the latter is set).</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Session limits</title>
+
+ <para>PAM modules earlier in the stack, that is those that come before <command>pam_systemd.so</command>,
+ can set session scope limits using the PAM context objects. The data for these objects is provided as NUL-terminated C strings
+ and maps directly to the respective unit resource control directives. Note that these limits apply to individual sessions of the user,
+ they do not apply to all user processes as a combined whole. In particular, the per-user <command>user@.service</command> unit instance,
+ which runs the <command>systemd --user</command> manager process and its children, and is tracked outside of any session, being shared
+ by all the user's sessions, is not covered by these limits.
+ </para>
+
+ <para> See
+ <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more information about the resources.
+ Also, see <citerefentry project='man-pages'><refentrytitle>pam_set_data</refentrytitle><manvolnum>3</manvolnum></citerefentry> for additional information about how to set
+ the context objects.
+ </para>
+
+ <variablelist class='pam-directives'>
+ <varlistentry>
+ <term><varname>systemd.memory_max=</varname></term>
+
+ <listitem><para>Sets unit <varname>MemoryMax=</varname>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.tasks_max=</varname></term>
+
+ <listitem><para>Sets unit <varname>TasksMax=</varname>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.cpu_weight=</varname></term>
+
+ <listitem><para>Sets unit <varname>CPUWeight=</varname>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.io_weight=</varname></term>
+
+ <listitem><para>Sets unit <varname>IOWeight=</varname>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.runtime_max_sec=</varname></term>
+
+ <listitem><para>Sets unit <varname>RuntimeMaxSec=</varname>.</para></listitem>
+ </varlistentry>
+ </variablelist>
+
+ <para>Example data as can be provided from an another PAM module:
+ <programlisting>
+pam_set_data(handle, "systemd.memory_max", (void *)"200M", cleanup);
+pam_set_data(handle, "systemd.tasks_max", (void *)"50", cleanup);
+pam_set_data(handle, "systemd.cpu_weight", (void *)"100", cleanup);
+pam_set_data(handle, "systemd.io_weight", (void *)"340", cleanup);
+pam_set_data(handle, "systemd.runtime_max_sec", (void *)"3600", cleanup);
+ </programlisting>
+ </para>
+
</refsect1>
<refsect1>
<title>Example</title>
+ <para>Here's an example PAM configuration fragment that allows users sessions to be managed by
+ <filename>systemd-logind.service</filename>:</para>
+
<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>
+auth sufficient pam_unix.so
+-auth sufficient pam_systemd_home.so
+auth required pam_deny.so
+
+account required pam_nologin.so
+-account sufficient pam_systemd_home.so
+account sufficient pam_unix.so
+account required pam_permit.so
+
+-password sufficient pam_systemd_home.so
+password sufficient pam_unix.so sha512 shadow try_first_pass try_authtok
+password required pam_deny.so
+
+-session optional pam_keyinit.so revoke
+-session optional pam_loginuid.so
+-session optional pam_systemd_home.so
+<command>-session optional pam_systemd.so</command>
+session required pam_unix.so</programlisting>
</refsect1>
<refsect1>
<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_systemd_home</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>pam.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>pam.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
projects / thirdparty / systemd.git / blobdiff