1<?xml version='1.0'?> <!--*-nxml-*-->
2<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
4<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
5
6<refentry id="systemd-sysusers"
7    xmlns:xi="http://www.w3.org/2001/XInclude">
8
9  <refentryinfo>
10    <title>systemd-sysusers</title>
11    <productname>systemd</productname>
12  </refentryinfo>
13
14  <refmeta>
15    <refentrytitle>systemd-sysusers</refentrytitle>
16    <manvolnum>8</manvolnum>
17  </refmeta>
18
19  <refnamediv>
20    <refname>systemd-sysusers</refname>
21    <refname>systemd-sysusers.service</refname>
22    <refpurpose>Allocate system users and groups</refpurpose>
23  </refnamediv>
24
25  <refsynopsisdiv>
26    <cmdsynopsis>
27      <command>systemd-sysusers</command>
28      <arg choice="opt" rep="repeat">OPTIONS</arg>
29      <arg choice="opt" rep="repeat"><replaceable>CONFIGFILE</replaceable></arg>
30    </cmdsynopsis>
31
32    <para><filename>systemd-sysusers.service</filename></para>
33  </refsynopsisdiv>
34
35  <refsect1>
36    <title>Description</title>
37
38    <para><command>systemd-sysusers</command> creates system users and
39    groups, based on the file format and location specified in
40    <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
41    </para>
42
43    <para>If invoked with no arguments, it applies all directives from all files
44    found in the directories specified by
45    <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
46    When invoked with positional arguments, if option
47    <option>--replace=<replaceable>PATH</replaceable></option> is specified, arguments
48    specified on the command line are used instead of the configuration file
49    <replaceable>PATH</replaceable>. Otherwise, just the configuration specified by
50    the command line arguments is executed. The string <literal>-</literal> may be
51    specified instead of a filename to instruct <command>systemd-sysusers</command>
52    to read the configuration from standard input. If only the basename of a file is
53    specified, all configuration directories are searched for a matching file and
54    the file found that has the highest priority is executed.</para>
55  </refsect1>
56
57  <refsect1>
58    <title>Options</title>
59
60    <para>The following options are understood:</para>
61
62    <variablelist>
63      <varlistentry>
64        <term><option>--root=<replaceable>root</replaceable></option></term>
65        <listitem><para>Takes a directory path as an argument. All
66        paths will be prefixed with the given alternate
67        <replaceable>root</replaceable> path, including config search
68        paths. </para></listitem>
69      </varlistentry>
70
71      <varlistentry>
72        <term><option>--image=<replaceable>image</replaceable></option></term>
73
74        <listitem><para>Takes a path to a disk image file or block device node. If specified all operations
75        are applied to file system in the indicated disk image. This is similar to <option>--root=</option>
76        but operates on file systems stored in disk images or block devices. The disk image should either
77        contain just a file system or a set of file systems within a GPT partition table, following the
78        <ulink url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable Partitions
79        Specification</ulink>. For further information on supported disk images, see
80        <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
81        switch of the same name.</para></listitem>
82      </varlistentry>
83
84      <varlistentry>
85        <term><option>--replace=<replaceable>PATH</replaceable></option></term>
86        <listitem><para>When this option is given, one or more positional arguments
87        must be specified. All configuration files found in the directories listed in
88        <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
89        will be read, and the configuration given on the command line will be
90        handled instead of and with the same priority as the configuration file
91        <replaceable>PATH</replaceable>.</para>
92
93        <para>This option is intended to be used when package installation scripts
94        are running and files belonging to that package are not yet available on
95        disk, so their contents must be given on the command line, but the admin
96        configuration might already exist and should be given higher priority.
97        </para>
98
99        <example>
100          <title>RPM installation script for radvd</title>
101
102          <programlisting>echo 'u radvd - "radvd daemon"' | \
103          systemd-sysusers --replace=/usr/lib/sysusers.d/radvd.conf -</programlisting>
104
105          <para>This will create the radvd user as if
106          <filename>/usr/lib/sysusers.d/radvd.conf</filename> was already on disk.
107          An admin might override the configuration specified on the command line by
108          placing <filename>/etc/sysusers.d/radvd.conf</filename> or even
109          <filename>/etc/sysusers.d/00-overrides.conf</filename>.</para>
110
111          <para>Note that this is the expanded form, and when used in a package, this
112          would be written using a macro with "radvd" and a file containing the
113          configuration line as arguments.</para>
114        </example>
115        </listitem>
116      </varlistentry>
117
118      <varlistentry>
119        <term><option>--dry-run</option></term>
120        <listitem><para>Process the configuration and figure out what entries would be created, but don't
121        actually write anything.</para></listitem>
122      </varlistentry>
123
124      <varlistentry>
125        <term><option>--inline</option></term>
126        <listitem><para>Treat each positional argument as a separate configuration
127        line instead of a file name.</para></listitem>
128      </varlistentry>
129
130      <xi:include href="standard-options.xml" xpointer="cat-config" />
131      <xi:include href="standard-options.xml" xpointer="no-pager" />
132      <xi:include href="standard-options.xml" xpointer="help" />
133      <xi:include href="standard-options.xml" xpointer="version" />
134    </variablelist>
135  </refsect1>
136
137  <refsect1>
138    <title>Credentials</title>
139
140    <para><command>systemd-sysusers</command> supports the service credentials logic as implemented by
141    <varname>LoadCredential=</varname>/<varname>SetCredential=</varname> (see
142    <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>1</manvolnum></citerefentry> for
143    details). The following credentials are used when passed in:</para>
144
145    <variablelist>
146      <varlistentry>
147        <term><literal>passwd.hashed-password.<replaceable>user</replaceable></literal></term>
148        <listitem><para>A UNIX hashed password string to use for the specified user, when creating an entry
149        for it. This is particularly useful for the <literal>root</literal> user as it allows provisioning
150        the default root password to use via a unit file drop-in or from a container manager passing in this
151        credential. Note that setting this credential has no effect if the specified user account already
152        exists. This credential is hence primarily useful in first boot scenarios or systems that are fully
153        stateless and come up with an empty <filename>/etc/</filename> on every boot.</para></listitem>
154      </varlistentry>
155
156      <varlistentry>
157        <term><literal>passwd.plaintext-password.<replaceable>user</replaceable></literal></term>
158
159        <listitem><para>Similar to <literal>passwd.hashed-password.<replaceable>user</replaceable></literal>
160        but expect a literal, plaintext password, which is then automatically hashed before used for the user
161        account. If both the hashed and the plaintext credential are specified for the same user the
162        former takes precedence. It's generally recommended to specify the hashed version; however in test
163        environments with weaker requirements on security it might be easier to pass passwords in plaintext
164        instead.</para></listitem>
165      </varlistentry>
166
167      <varlistentry>
168        <term><literal>passwd.shell.<replaceable>user</replaceable></literal></term>
169
170        <listitem><para>Specifies the shell binary to use for the specified account when creating it.</para></listitem>
171      </varlistentry>
172    </variablelist>
173
174    <para>Note that by default the <filename>systemd-sysusers.service</filename> unit file is set up to
175    inherit the <literal>passwd.hashed-password.root</literal>,
176    <literal>passwd.plaintext-password.root</literal> and <literal>passwd.shell.root</literal> credentials
177    from the service manager. Thus, when invoking a container with an unpopulated <filename>/etc/</filename>
178    for the first time it is possible to configure the root user's password to be <literal>systemd</literal>
179    like this:</para>
180
181    <para><programlisting># systemd-nspawn --image=… --set-credential=passwd.hashed-password.root:'$y$j9T$yAuRJu1o5HioZAGDYPU5d.$F64ni6J2y2nNQve90M/p0ZP0ECP/qqzipNyaY9fjGpC' …</programlisting></para>
182
183    <para>Note again that the data specified in these credentials is consulted only when creating an account
184    for the first time, it may not be used for changing the password or shell of an account that already
185    exists.</para>
186
187    <para>Use <citerefentry project='man-pages'><refentrytitle>mkpasswd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
188    for generating UNIX password hashes from the command line.</para>
189  </refsect1>
190
191  <refsect1>
192    <title>Exit status</title>
193
194    <para>On success, 0 is returned, a non-zero failure code
195    otherwise.</para>
196  </refsect1>
197
198  <refsect1>
199    <title>See Also</title>
200    <para>
201      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
202      <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
203      <ulink url="https://systemd.io/UIDS-GIDS">Users, Groups, UIDs and GIDs on systemd systems</ulink>,
204      <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
205      <citerefentry project='man-pages'><refentrytitle>mkpasswd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
206    </para>
207  </refsect1>
208
209</refentry>
210