man/sysusers.d.xml - systemd-stable - Rivoreo Source Code Repositories

 <?xml version="1.0"?>
 <!--*-nxml-*-->
 <!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+ -->
 <refentry id="sysusers.d" conditional='ENABLE_SYSUSERS'
     xmlns:xi="http://www.w3.org/2001/XInclude">

   <refentryinfo>
     <title>sysusers.d</title>
     <productname>systemd</productname>
   </refentryinfo>

   <refmeta>
     <refentrytitle>sysusers.d</refentrytitle>
     <manvolnum>5</manvolnum>
   </refmeta>

   <refnamediv>
     <refname>sysusers.d</refname>
     <refpurpose>Declarative allocation of system users and groups</refpurpose>
   </refnamediv>

   <refsynopsisdiv>
     <para><filename>/etc/sysusers.d/*.conf</filename></para>
     <para><filename>/run/sysusers.d/*.conf</filename></para>
     <para><filename>/usr/lib/sysusers.d/*.conf</filename></para>

     <programlisting>
 #Type Name       ID                  GECOS              Home directory Shell
 u     user_name  uid                 "User Description" /home/dir      /path/to/shell
 u     user_name  uid:gid             "User Description" /home/dir      /path/to/shell
 u     user_name  /file/owned/by/user "User Description" /home/dir      /path/to/shell
 g     group_name gid
 g     group_name /file/owned/by/group
 m     user_name  group_name
 r     -          lowest-highest</programlisting>
   </refsynopsisdiv>

   <refsect1>
     <title>Description</title>

     <para><command>systemd-sysusers</command> uses the files from
     <filename>sysusers.d</filename> directory to create system users and groups and
     to add users to groups, at package installation or boot time. This tool may be
     used to allocate system users and groups only, it is not useful for creating
     non-system (i.e. regular, "human") users and groups, as it accesses
     <filename>/etc/passwd</filename> and <filename>/etc/group</filename> directly,
     bypassing any more complex user databases, for example any database involving NIS
     or LDAP.</para>
   </refsect1>

   <refsect1>
     <title>Configuration Directories and Precedence</title>

     <para>Each configuration file shall be named in the style of
     <filename><replaceable>package</replaceable>.conf</filename> or
     <filename><replaceable>package</replaceable>-<replaceable>part</replaceable>.conf</filename>.
     The second variant should be used when it is desirable to make it
     easy to override just this part of configuration.</para>

     <para>Files in <filename>/etc/sysusers.d</filename> override files
     with the same name in <filename>/usr/lib/sysusers.d</filename> and
     <filename>/run/sysusers.d</filename>. Files in
     <filename>/run/sysusers.d</filename> override files with the same
     name in <filename>/usr/lib/sysusers.d</filename>. Packages should
     install their configuration files in
     <filename>/usr/lib/sysusers.d</filename>. Files in
     <filename>/etc/sysusers.d</filename> are reserved for the local
     administrator, who may use this logic to override the
     configuration files installed by vendor packages. All
     configuration files are sorted by their filename in lexicographic
     order, regardless of which of the directories they reside in. If
     multiple files specify the same path, the entry in the file with
     the lexicographically earliest name will be applied. All later
     entries for the same user and group names will be logged as warnings.
     </para>

     <para>If the administrator wants to disable a configuration file
     supplied by the vendor, the recommended way is to place a symlink
     to <filename>/dev/null</filename> in
     <filename>/etc/sysusers.d/</filename> bearing the same filename.
     </para>
   </refsect1>

   <refsect1>
     <title>Configuration File Format</title>

     <para>The file format is one line per user or group containing name, ID, GECOS
     field description, home directory, and login shell:</para>

     <programlisting>#Type Name     ID             GECOS                 Home directory Shell
 u     httpd    404            "HTTP User"
 u     _authd   /usr/bin/authd "Authorization user"
 u     postgres -              "Postgresql Database" /var/lib/pgsql /usr/libexec/postgresdb
 g     input    -              -
 m     _authd   input
 u     root     0              "Superuser"           /root          /bin/zsh
 r     -        500-900
 </programlisting>

     <para>Empty lines and lines beginning with the <literal>#</literal> character are ignored, and may be used for
     commenting.</para>

     <refsect2>
       <title>Type</title>

       <para>The type consists of a single letter. The following line
       types are understood:</para>

       <variablelist>
         <varlistentry>
           <term><varname>u</varname></term>
           <listitem><para>Create a system user and group of the specified name should
           they not exist yet. The user's primary group will be set to the group
           bearing the same name unless the ID field specifies it. The account will be
           created disabled, so that logins are not allowed.</para></listitem>
         </varlistentry>

         <varlistentry>
           <term><varname>g</varname></term>
           <listitem><para>Create a system group of the specified name
           should it not exist yet. Note that <varname>u</varname>
           implicitly creates a matching group. The group will be
           created with no password set.</para></listitem>
         </varlistentry>

         <varlistentry>
           <term><varname>m</varname></term>
           <listitem><para>Add a user to a group. If the user or group
           do not exist yet, they will be implicitly
           created.</para></listitem>
         </varlistentry>

         <varlistentry>
           <term><varname>r</varname></term>
           <listitem><para>Add a range of numeric UIDs/GIDs to the pool
           to allocate new UIDs and GIDs from. If no line of this type
           is specified, the range of UIDs/GIDs is set to some
           compiled-in default. Note that both UIDs and GIDs are
           allocated from the same pool, in order to ensure that users
           and groups of the same name are likely to carry the same
           numeric UID and GID.</para></listitem>
         </varlistentry>

       </variablelist>
     </refsect2>

     <refsect2>
       <title>Name</title>

       <para>The name field specifies the user or group name. The specified name must consist only of the characters a-z,
       A-Z, 0-9, <literal>_</literal> and <literal>-</literal>, except for the first character which must be one of a-z,
       A-Z or <literal>_</literal> (i.e. numbers and <literal>-</literal> are not permitted as first character). The
       user/group name must have at least one character, and at most 31.</para>

       <para>For further details about the syntax of user/group names, see <ulink
       url="https://systemd.io/USER_NAMES">User/Group Name Syntax</ulink>.</para>

       <para>It is strongly recommended to pick user and group names that are unlikely to clash with normal users
       created by the administrator. A good scheme to guarantee this is by prefixing all system and group names with the
       underscore, and avoiding too generic names.</para>

       <para>For <varname>m</varname> lines, this field should contain
       the user name to add to a group.</para>

       <para>For lines of type <varname>r</varname>, this field should
       be set to <literal>-</literal>.</para>
     </refsect2>

     <refsect2>
       <title>ID</title>

       <para>For <varname>u</varname> and <varname>g</varname>, the
       numeric 32-bit UID or GID of the user/group. Do not use IDs 65535
       or 4294967295, as they have special placeholder meanings.
       Specify <literal>-</literal> for automatic UID/GID allocation
       for the user or group (this is strongly recommended unless it is strictly
       necessary to use a specific UID or GID). Alternatively, specify an absolute path
       in the file system. In this case, the UID/GID is read from the
       path's owner/group. This is useful to create users whose UID/GID
       match the owners of pre-existing files (such as SUID or SGID
       binaries).
       The syntaxes <literal><replaceable>uid</replaceable>:<replaceable>gid</replaceable></literal> and
       <literal><replaceable>uid</replaceable>:<replaceable>groupname</replaceable></literal> are supported to
       allow creating users with specific primary groups. The given group must be created explicitly, or it
       must already exist. Specifying <literal>-</literal> for the UID in these syntaxes is also supported.
       </para>

       <para>For <varname>m</varname> lines, this field should contain
       the group name to add to a user to.</para>

       <para>For lines of type <varname>r</varname>, this field should
       be set to a UID/GID range in the format
       <literal>FROM-TO</literal>, where both values are formatted as
       decimal ASCII numbers. Alternatively, a single UID/GID may be
       specified formatted as decimal ASCII numbers.</para>
     </refsect2>

     <refsect2>
       <title>GECOS</title>

       <para>A short, descriptive string for users to be created, enclosed in
       quotation marks. Note that this field may not contain colons.</para>

       <para>Only applies to lines of type <varname>u</varname> and should otherwise
       be left unset (or <literal>-</literal>).</para>
     </refsect2>

     <refsect2>
       <title>Home Directory</title>

       <para>The home directory for a new system user. If omitted, defaults to the
       root directory.</para>

       <para>Only applies to lines of type <varname>u</varname> and should otherwise
       be left unset (or <literal>-</literal>). It is recommended to omit this, unless
       software strictly requires a home directory to be set.</para>
     </refsect2>

     <refsect2>
       <title>Shell</title>

       <para>The login shell of the user. If not specified, this will be set to
       <filename>/usr/sbin/nologin</filename>, except if the UID of the user is 0, in
       which case <filename>/bin/sh</filename> will be used.</para>

       <para>Only applies to lines of type <varname>u</varname> and should otherwise
       be left unset (or <literal>-</literal>). It is recommended to omit this, unless
       a shell different <filename>/usr/sbin/nologin</filename> must be used.</para>
     </refsect2>
   </refsect1>

   <refsect1>
     <title>Specifiers</title>

     <para>Specifiers can be used in the <literal>Name</literal>, <literal>ID</literal>,
     <literal>GECOS</literal>, <literal>Home directory</literal>, and <literal>Shell</literal> fields. An
     unknown or unresolvable specifier is treated as invalid configuration. The following expansions are
     understood:</para>

     <table class='specifiers'>
       <title>Specifiers available</title>
       <tgroup cols='3' align='left' colsep='1' rowsep='1'>
         <colspec colname="spec" />
         <colspec colname="mean" />
         <colspec colname="detail" />
         <thead>
           <row>
             <entry>Specifier</entry>
             <entry>Meaning</entry>
             <entry>Details</entry>
           </row>
         </thead>
         <tbody>
           <xi:include href="standard-specifiers.xml" xpointer="a"/>
           <xi:include href="standard-specifiers.xml" xpointer="b"/>
           <xi:include href="standard-specifiers.xml" xpointer="B"/>
           <xi:include href="standard-specifiers.xml" xpointer="H"/>
           <xi:include href="standard-specifiers.xml" xpointer="l"/>
           <xi:include href="standard-specifiers.xml" xpointer="m"/>
           <xi:include href="standard-specifiers.xml" xpointer="o"/>
           <row>
             <entry><literal>%T</literal></entry>
             <entry>Directory for temporary files</entry>
             <entry>This is either <filename>/tmp</filename> or the path <literal>$TMPDIR</literal>, <literal>$TEMP</literal> or <literal>$TMP</literal> are set to.</entry>
           </row>
           <xi:include href="standard-specifiers.xml" xpointer="v"/>
           <row>
             <entry><literal>%V</literal></entry>
             <entry>Directory for larger and persistent temporary files</entry>
             <entry>This is either <filename>/var/tmp</filename> or the path <literal>$TMPDIR</literal>, <literal>$TEMP</literal> or <literal>$TMP</literal> are set to.</entry>
           </row>
           <xi:include href="standard-specifiers.xml" xpointer="w"/>
           <xi:include href="standard-specifiers.xml" xpointer="W"/>
           <xi:include href="standard-specifiers.xml" xpointer="percent"/>
         </tbody>
       </tgroup>
     </table>
   </refsect1>

   <refsect1>
     <title>Idempotence</title>

     <para>Note that <command>systemd-sysusers</command> will do nothing if the
     specified users or groups already exist or the users are members of specified
     groups, so normally there is no reason to override
     <filename>sysusers.d</filename> vendor configuration, except to block certain
     users or groups from being created.</para>
   </refsect1>

   <refsect1>
     <title>See Also</title>
     <para>
       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
       <citerefentry><refentrytitle>systemd-sysusers</refentrytitle><manvolnum>8</manvolnum></citerefentry>
     </para>
   </refsect1>

 </refentry>
	<?xml version="1.0"?>
	<!---nxml--->
	<!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+ -->
	<refentry id="sysusers.d" conditional='ENABLE_SYSUSERS'
	xmlns:xi="http://www.w3.org/2001/XInclude">

	<refentryinfo>
	<title>sysusers.d</title>
	<productname>systemd</productname>
	</refentryinfo>

	<refmeta>
	<refentrytitle>sysusers.d</refentrytitle>
	<manvolnum>5</manvolnum>
	</refmeta>

	<refnamediv>
	<refname>sysusers.d</refname>
	<refpurpose>Declarative allocation of system users and groups</refpurpose>
	</refnamediv>

	<refsynopsisdiv>
	<para><filename>/etc/sysusers.d/*.conf</filename></para>
	<para><filename>/run/sysusers.d/*.conf</filename></para>
	<para><filename>/usr/lib/sysusers.d/*.conf</filename></para>

	<programlisting>
	#Type Name ID GECOS Home directory Shell
	u user_name uid "User Description" /home/dir /path/to/shell
	u user_name uid:gid "User Description" /home/dir /path/to/shell
	u user_name /file/owned/by/user "User Description" /home/dir /path/to/shell
	g group_name gid
	g group_name /file/owned/by/group
	m user_name group_name
	r - lowest-highest</programlisting>
	</refsynopsisdiv>

	<refsect1>
	<title>Description</title>

	<para><command>systemd-sysusers</command> uses the files from
	<filename>sysusers.d</filename> directory to create system users and groups and
	to add users to groups, at package installation or boot time. This tool may be
	used to allocate system users and groups only, it is not useful for creating
	non-system (i.e. regular, "human") users and groups, as it accesses
	<filename>/etc/passwd</filename> and <filename>/etc/group</filename> directly,
	bypassing any more complex user databases, for example any database involving NIS
	or LDAP.</para>
	</refsect1>

	<refsect1>
	<title>Configuration Directories and Precedence</title>

	<para>Each configuration file shall be named in the style of
	<filename><replaceable>package</replaceable>.conf</filename> or
	<filename><replaceable>package</replaceable>-<replaceable>part</replaceable>.conf</filename>.
	The second variant should be used when it is desirable to make it
	easy to override just this part of configuration.</para>

	<para>Files in <filename>/etc/sysusers.d</filename> override files
	with the same name in <filename>/usr/lib/sysusers.d</filename> and
	<filename>/run/sysusers.d</filename>. Files in
	<filename>/run/sysusers.d</filename> override files with the same
	name in <filename>/usr/lib/sysusers.d</filename>. Packages should
	install their configuration files in
	<filename>/usr/lib/sysusers.d</filename>. Files in
	<filename>/etc/sysusers.d</filename> are reserved for the local
	administrator, who may use this logic to override the
	configuration files installed by vendor packages. All
	configuration files are sorted by their filename in lexicographic
	order, regardless of which of the directories they reside in. If
	multiple files specify the same path, the entry in the file with
	the lexicographically earliest name will be applied. All later
	entries for the same user and group names will be logged as warnings.
	</para>

	<para>If the administrator wants to disable a configuration file
	supplied by the vendor, the recommended way is to place a symlink
	to <filename>/dev/null</filename> in
	<filename>/etc/sysusers.d/</filename> bearing the same filename.
	</para>
	</refsect1>

	<refsect1>
	<title>Configuration File Format</title>

	<para>The file format is one line per user or group containing name, ID, GECOS
	field description, home directory, and login shell:</para>

	<programlisting>#Type Name ID GECOS Home directory Shell
	u httpd 404 "HTTP User"
	u _authd /usr/bin/authd "Authorization user"
	u postgres - "Postgresql Database" /var/lib/pgsql /usr/libexec/postgresdb
	g input - -
	m _authd input
	u root 0 "Superuser" /root /bin/zsh
	r - 500-900
	</programlisting>

	<para>Empty lines and lines beginning with the <literal>#</literal> character are ignored, and may be used for
	commenting.</para>

	<refsect2>
	<title>Type</title>

	<para>The type consists of a single letter. The following line
	types are understood:</para>

	<variablelist>
	<varlistentry>
	<term><varname>u</varname></term>
	<listitem><para>Create a system user and group of the specified name should
	they not exist yet. The user's primary group will be set to the group
	bearing the same name unless the ID field specifies it. The account will be
	created disabled, so that logins are not allowed.</para></listitem>
	</varlistentry>

	<varlistentry>
	<term><varname>g</varname></term>
	<listitem><para>Create a system group of the specified name
	should it not exist yet. Note that <varname>u</varname>
	implicitly creates a matching group. The group will be
	created with no password set.</para></listitem>
	</varlistentry>

	<varlistentry>
	<term><varname>m</varname></term>
	<listitem><para>Add a user to a group. If the user or group
	do not exist yet, they will be implicitly
	created.</para></listitem>
	</varlistentry>

	<varlistentry>
	<term><varname>r</varname></term>
	<listitem><para>Add a range of numeric UIDs/GIDs to the pool
	to allocate new UIDs and GIDs from. If no line of this type
	is specified, the range of UIDs/GIDs is set to some
	compiled-in default. Note that both UIDs and GIDs are
	allocated from the same pool, in order to ensure that users
	and groups of the same name are likely to carry the same
	numeric UID and GID.</para></listitem>
	</varlistentry>

	</variablelist>
	</refsect2>

	<refsect2>
	<title>Name</title>

	<para>The name field specifies the user or group name. The specified name must consist only of the characters a-z,
	A-Z, 0-9, <literal>_</literal> and <literal>-</literal>, except for the first character which must be one of a-z,
	A-Z or <literal>_</literal> (i.e. numbers and <literal>-</literal> are not permitted as first character). The
	user/group name must have at least one character, and at most 31.</para>

	<para>For further details about the syntax of user/group names, see <ulink
	url="https://systemd.io/USER_NAMES">User/Group Name Syntax</ulink>.</para>

	<para>It is strongly recommended to pick user and group names that are unlikely to clash with normal users
	created by the administrator. A good scheme to guarantee this is by prefixing all system and group names with the
	underscore, and avoiding too generic names.</para>

	<para>For <varname>m</varname> lines, this field should contain
	the user name to add to a group.</para>

	<para>For lines of type <varname>r</varname>, this field should
	be set to <literal>-</literal>.</para>
	</refsect2>

	<refsect2>
	<title>ID</title>

	<para>For <varname>u</varname> and <varname>g</varname>, the
	numeric 32-bit UID or GID of the user/group. Do not use IDs 65535
	or 4294967295, as they have special placeholder meanings.
	Specify <literal>-</literal> for automatic UID/GID allocation
	for the user or group (this is strongly recommended unless it is strictly
	necessary to use a specific UID or GID). Alternatively, specify an absolute path
	in the file system. In this case, the UID/GID is read from the
	path's owner/group. This is useful to create users whose UID/GID
	match the owners of pre-existing files (such as SUID or SGID
	binaries).
	The syntaxes <literal><replaceable>uid</replaceable>:<replaceable>gid</replaceable></literal> and
	<literal><replaceable>uid</replaceable>:<replaceable>groupname</replaceable></literal> are supported to
	allow creating users with specific primary groups. The given group must be created explicitly, or it
	must already exist. Specifying <literal>-</literal> for the UID in these syntaxes is also supported.
	</para>

	<para>For <varname>m</varname> lines, this field should contain
	the group name to add to a user to.</para>

	<para>For lines of type <varname>r</varname>, this field should
	be set to a UID/GID range in the format
	<literal>FROM-TO</literal>, where both values are formatted as
	decimal ASCII numbers. Alternatively, a single UID/GID may be
	specified formatted as decimal ASCII numbers.</para>
	</refsect2>

	<refsect2>
	<title>GECOS</title>

	<para>A short, descriptive string for users to be created, enclosed in
	quotation marks. Note that this field may not contain colons.</para>

	<para>Only applies to lines of type <varname>u</varname> and should otherwise
	be left unset (or <literal>-</literal>).</para>
	</refsect2>

	<refsect2>
	<title>Home Directory</title>

	<para>The home directory for a new system user. If omitted, defaults to the
	root directory.</para>

	<para>Only applies to lines of type <varname>u</varname> and should otherwise
	be left unset (or <literal>-</literal>). It is recommended to omit this, unless
	software strictly requires a home directory to be set.</para>
	</refsect2>

	<refsect2>
	<title>Shell</title>

	<para>The login shell of the user. If not specified, this will be set to
	<filename>/usr/sbin/nologin</filename>, except if the UID of the user is 0, in
	which case <filename>/bin/sh</filename> will be used.</para>

	<para>Only applies to lines of type <varname>u</varname> and should otherwise
	be left unset (or <literal>-</literal>). It is recommended to omit this, unless
	a shell different <filename>/usr/sbin/nologin</filename> must be used.</para>
	</refsect2>
	</refsect1>

	<refsect1>
	<title>Specifiers</title>

	<para>Specifiers can be used in the <literal>Name</literal>, <literal>ID</literal>,
	<literal>GECOS</literal>, <literal>Home directory</literal>, and <literal>Shell</literal> fields. An
	unknown or unresolvable specifier is treated as invalid configuration. The following expansions are
	understood:</para>

	<table class='specifiers'>
	<title>Specifiers available</title>
	<tgroup cols='3' align='left' colsep='1' rowsep='1'>
	<colspec colname="spec" />
	<colspec colname="mean" />
	<colspec colname="detail" />
	<thead>
	<row>
	<entry>Specifier</entry>
	<entry>Meaning</entry>
	<entry>Details</entry>
	</row>
	</thead>
	<tbody>
	<xi:include href="standard-specifiers.xml" xpointer="a"/>
	<xi:include href="standard-specifiers.xml" xpointer="b"/>
	<xi:include href="standard-specifiers.xml" xpointer="B"/>
	<xi:include href="standard-specifiers.xml" xpointer="H"/>
	<xi:include href="standard-specifiers.xml" xpointer="l"/>
	<xi:include href="standard-specifiers.xml" xpointer="m"/>
	<xi:include href="standard-specifiers.xml" xpointer="o"/>
	<row>
	<entry><literal>%T</literal></entry>
	<entry>Directory for temporary files</entry>
	<entry>This is either <filename>/tmp</filename> or the path <literal>$TMPDIR</literal>, <literal>$TEMP</literal> or <literal>$TMP</literal> are set to.</entry>
	</row>
	<xi:include href="standard-specifiers.xml" xpointer="v"/>
	<row>
	<entry><literal>%V</literal></entry>
	<entry>Directory for larger and persistent temporary files</entry>
	<entry>This is either <filename>/var/tmp</filename> or the path <literal>$TMPDIR</literal>, <literal>$TEMP</literal> or <literal>$TMP</literal> are set to.</entry>
	</row>
	<xi:include href="standard-specifiers.xml" xpointer="w"/>
	<xi:include href="standard-specifiers.xml" xpointer="W"/>
	<xi:include href="standard-specifiers.xml" xpointer="percent"/>
	</tbody>
	</tgroup>
	</table>
	</refsect1>

	<refsect1>
	<title>Idempotence</title>

	<para>Note that <command>systemd-sysusers</command> will do nothing if the
	specified users or groups already exist or the users are members of specified
	groups, so normally there is no reason to override
	<filename>sysusers.d</filename> vendor configuration, except to block certain
	users or groups from being created.</para>
	</refsect1>

	<refsect1>
	<title>See Also</title>
	<para>
	<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
	<citerefentry><refentrytitle>systemd-sysusers</refentrytitle><manvolnum>8</manvolnum></citerefentry>
	</para>
	</refsect1>

	</refentry>