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| <!-- SPDX-License-Identifier: LGPL-2.1-or-later --> |
| |
| <refentry id="userdbctl" conditional='ENABLE_USERDB' |
| xmlns:xi="http://www.w3.org/2001/XInclude"> |
| |
| <refentryinfo> |
| <title>userdbctl</title> |
| <productname>systemd</productname> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle>userdbctl</refentrytitle> |
| <manvolnum>1</manvolnum> |
| </refmeta> |
| |
| <refnamediv> |
| <refname>userdbctl</refname> |
| <refpurpose>Inspect users, groups and group memberships</refpurpose> |
| </refnamediv> |
| |
| <refsynopsisdiv> |
| <cmdsynopsis> |
| <command>userdbctl</command> |
| <arg choice="opt" rep="repeat">OPTIONS</arg> |
| <arg choice="req">COMMAND</arg> |
| <arg choice="opt" rep="repeat">NAME</arg> |
| </cmdsynopsis> |
| </refsynopsisdiv> |
| |
| <refsect1> |
| <title>Description</title> |
| |
| <para><command>userdbctl</command> may be used to inspect user and groups (as well as group memberships) |
| of the system. This client utility inquires user/group information provided by various system services, |
| both operating on JSON user/group records (as defined by the <ulink |
| url="https://systemd.io/USER_RECORD">JSON User Records</ulink> and <ulink |
| url="https://systemd.io/GROUP_RECORD">JSON Group Records</ulink> definitions), and classic UNIX NSS/glibc |
| user and group records. This tool is primarily a client to the <ulink |
| url="https://systemd.io/USER_GROUP_API">User/Group Record Lookup API via Varlink</ulink>, and may also |
| pick up drop-in JSON user and group records from <filename>/etc/userdb/</filename>, |
| <filename>/run/userdb/</filename>, <filename>/run/host/userdb/</filename>, |
| <filename>/usr/lib/userdb/</filename>.</para> |
| </refsect1> |
| |
| <refsect1> |
| <title>Options</title> |
| |
| <para>The following options are understood:</para> |
| |
| <variablelist> |
| |
| <varlistentry> |
| <term><option>--output=</option><replaceable>MODE</replaceable></term> |
| |
| <listitem><para>Choose the output mode, takes one of <literal>classic</literal>, |
| <literal>friendly</literal>, <literal>table</literal>, <literal>json</literal>. If |
| <literal>classic</literal>, an output very close to the format of <filename>/etc/passwd</filename> or |
| <filename>/etc/group</filename> is generated. If <literal>friendly</literal> a more comprehensive and |
| user friendly, human readable output is generated; if <literal>table</literal> a minimal, tabular |
| output is generated; if <literal>json</literal> a JSON formatted output is generated. Defaults to |
| <literal>friendly</literal> if a user/group is specified on the command line, |
| <literal>table</literal> otherwise.</para> |
| |
| <para>Note that most output formats do not show all available information. In particular, |
| <literal>classic</literal> and <literal>table</literal> show only the most important fields. Various |
| modes also do not show password hashes. Use <literal>json</literal> to view all fields, including |
| any authentication fields.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--json=</option><replaceable>FORMAT</replaceable></term> |
| |
| <listitem><para>Selects JSON output mode (like <option>--output=json</option>) and selects the |
| precise display mode. Takes one of <literal>pretty</literal> or <literal>short</literal>. If |
| <literal>pretty</literal>, human-friendly whitespace and newlines are inserted in the output to make |
| the JSON data more readable. If <literal>short</literal>, all superfluous whitespace is |
| suppressed.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--service=</option><replaceable>SERVICE</replaceable><optional>:<replaceable>SERVICE…</replaceable></optional></term> |
| <term><option>-s</option> <replaceable>SERVICE</replaceable>:<replaceable>SERVICE…</replaceable></term> |
| |
| <listitem><para>Controls which services to query for users/groups. Takes a list of one or more |
| service names, separated by <literal>:</literal>. See below for a list of well-known service |
| names. If not specified all available services are queried at once.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--with-nss=</option><replaceable>BOOL</replaceable></term> |
| |
| <listitem><para>Controls whether to include classic glibc/NSS user/group lookups in the output. If |
| <option>--with-nss=no</option> is used any attempts to resolve or enumerate users/groups provided |
| only via glibc NSS is suppressed. If <option>--with-nss=yes</option> is specified such users/groups |
| are included in the output (which is the default).</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--with-varlink=</option><replaceable>BOOL</replaceable></term> |
| |
| <listitem><para>Controls whether to include Varlink user/group lookups in the output, i.e. those done |
| via the <ulink url="https://systemd.io/USER_GROUP_API">User/Group Record Lookup API via |
| Varlink</ulink>. If <option>--with-varlink=no</option> is used any attempts to resolve or enumerate |
| users/groups provided only via Varlink are suppressed. If <option>--with-varlink=yes</option> is |
| specified such users/groups are included in the output (which is the default).</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--with-dropin=</option><replaceable>BOOL</replaceable></term> |
| |
| <listitem><para>Controls whether to include user/group lookups in the output that are defined using |
| drop-in files in <filename>/etc/userdb/</filename>, <filename>/run/userdb/</filename>, |
| <filename>/run/host/userdb/</filename>, <filename>/usr/lib/userdb/</filename>. If |
| <option>--with-dropin=no</option> is used these records are suppressed. If |
| <option>--with-dropin=yes</option> is specified such users/groups are included in the output (which |
| is the default).</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--synthesize=</option><replaceable>BOOL</replaceable></term> |
| |
| <listitem><para>Controls whether to synthesize records for the root and nobody users/groups if they |
| aren't defined otherwise. By default (or <literal>yes</literal>) such records are implicitly |
| synthesized if otherwise missing since they have special significance to the OS. When |
| <literal>no</literal> this synthesizing is turned off.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-N</option></term> |
| |
| <listitem><para>This option is short for <option>--with-nss=no</option> |
| <option>--synthesize=no</option>. Use this option to show only records that are natively defined as |
| JSON user or group records, with all NSS/glibc compatibility and all implicit synthesis turned |
| off.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--multiplexer=</option><replaceable>BOOL</replaceable></term> |
| |
| <listitem><para>Controls whether to do lookups via the multiplexer service (if specified as true, the |
| default) or do lookups in the client (if specified as false). Using the multiplexer service is |
| typically preferable, since it runs in a locked down sandbox.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--chain</option></term> |
| |
| <listitem><para>When used with the <command>ssh-authorized-keys</command> command, this will allow |
| passing an additional command line after the user name that is chain executed after the lookup |
| completed. This allows chaining multiple tools that show SSH authorized keys.</para></listitem> |
| </varlistentry> |
| |
| <xi:include href="standard-options.xml" xpointer="no-pager" /> |
| <xi:include href="standard-options.xml" xpointer="no-legend" /> |
| <xi:include href="standard-options.xml" xpointer="help" /> |
| <xi:include href="standard-options.xml" xpointer="version" /> |
| </variablelist> |
| </refsect1> |
| |
| <refsect1> |
| <title>Commands</title> |
| |
| <para>The following commands are understood:</para> |
| |
| <variablelist> |
| |
| <varlistentry> |
| <term><command>user</command> <optional><replaceable>USER</replaceable>…</optional></term> |
| |
| <listitem><para>List all known users records or show details of one or more specified user |
| records. Use <option>--output=</option> to tweak output mode.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><command>group</command> <optional><replaceable>GROUP</replaceable>…</optional></term> |
| |
| <listitem><para>List all known group records or show details of one or more specified group |
| records. Use <option>--output=</option> to tweak output mode.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><command>users-in-group</command> <optional><replaceable>GROUP</replaceable>…</optional></term> |
| |
| <listitem><para>List users that are members of the specified groups. If no groups are specified list |
| all user/group memberships defined. Use <option>--output=</option> to tweak output |
| mode.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><command>groups-of-user</command> <optional><replaceable>USER</replaceable>…</optional></term> |
| |
| <listitem><para>List groups that the specified users are members of. If no users are specified list |
| all user/group memberships defined (in this case <command>groups-of-user</command> and |
| <command>users-in-group</command> are equivalent). Use <option>--output=</option> to tweak output |
| mode.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><command>services</command></term> |
| |
| <listitem><para>List all services currently providing user/group definitions to the system. See below |
| for a list of well-known services providing user information.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><command>ssh-authorized-keys</command></term> |
| |
| <listitem><para>Show SSH authorized keys for this account. This command is intended to be used to |
| allow the SSH daemon to pick up authorized keys from user records, see below.</para></listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| |
| <refsect1> |
| <title>Well-Known Services</title> |
| |
| <para>The <command>userdbctl services</command> command will list all currently running services that |
| provide user or group definitions to the system. The following well-known services are shown among |
| this list:</para> |
| |
| <variablelist> |
| <varlistentry> |
| <term><constant>io.systemd.DynamicUser</constant></term> |
| |
| <listitem><para>This service is provided by the system service manager itself (i.e. PID 1) and |
| makes all users (and their groups) synthesized through the <varname>DynamicUser=</varname> setting in |
| service unit files available to the system (see |
| <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for |
| details about this setting).</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><constant>io.systemd.Home</constant></term> |
| |
| <listitem><para>This service is provided by |
| <citerefentry><refentrytitle>systemd-homed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
| and makes all users (and their groups) belonging to home directories managed by that service |
| available to the system.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><constant>io.systemd.Machine</constant></term> |
| |
| <listitem><para>This service is provided by |
| <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
| and synthesizes records for all users/groups used by a container that employs user |
| namespacing.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><constant>io.systemd.Multiplexer</constant></term> |
| |
| <listitem><para>This service is provided by |
| <citerefentry><refentrytitle>systemd-userdbd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
| and multiplexes user/group look-ups to all other running lookup services. This is the primary entry point |
| for user/group record clients, as it simplifies client side implementation substantially since they |
| can ask a single service for lookups instead of asking all running services in parallel. |
| <command>userdbctl</command> uses this service preferably, too, unless <option>--with-nss=</option> |
| or <option>--service=</option> are used, in which case finer control over the services to talk to is |
| required.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><constant>io.systemd.NameServiceSwitch</constant></term> |
| |
| <listitem><para>This service is (also) provided by |
| <citerefentry><refentrytitle>systemd-userdbd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
| and converts classic NSS/glibc user and group records to JSON user/group records, providing full |
| backwards compatibility. Use <option>--with-nss=no</option> to disable this compatibility, see |
| above. Note that compatibility is actually provided in both directions: |
| <citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry> will |
| automatically synthesize classic NSS/glibc user/group records from all JSON user/group records |
| provided to the system, thus using both APIs is mostly equivalent and provides access to the same |
| data, however the NSS/glibc APIs necessarily expose a more reduced set of fields |
| only.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><constant>io.systemd.DropIn</constant></term> |
| |
| <listitem><para>This service is (also) provided by |
| <citerefentry><refentrytitle>systemd-userdbd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
| and picks up JSON user/group records from <filename>/etc/userdb/</filename>, |
| <filename>/run/userdb/</filename>, <filename>/run/host/userdb/</filename>, |
| <filename>/usr/lib/userdb/</filename>.</para></listitem> |
| </varlistentry> |
| |
| </variablelist> |
| |
| <para>Note that <command>userdbctl</command> has internal support for NSS-based lookups too. This means |
| that if neither <constant>io.systemd.Multiplexer</constant> nor |
| <constant>io.systemd.NameServiceSwitch</constant> are running look-ups into the basic user/group |
| databases will still work.</para> |
| </refsect1> |
| |
| <refsect1> |
| <title>Integration with SSH</title> |
| |
| <para>The <command>userdbctl</command> tool may be used to make the list of SSH authorized keys possibly |
| contained in a user record available to the SSH daemon for authentication. For that configure the |
| following in <citerefentry |
| project='die-net'><refentrytitle>sshd_config</refentrytitle><manvolnum>5</manvolnum></citerefentry>:</para> |
| |
| <programlisting>… |
| AuthorizedKeysCommand /usr/bin/userdbctl ssh-authorized-keys %u |
| AuthorizedKeysCommandUser root |
| …</programlisting> |
| |
| <para>Sometimes it's useful to allow chain invocation of another program to list SSH authorized keys. By |
| using the <option>--chain</option> such a tool may be chain executed by <command>userdbctl |
| ssh-authorized-keys</command> once a lookup completes (regardless if an SSH key was found or |
| not). Example:</para> |
| |
| <programlisting>… |
| AuthorizedKeysCommand /usr/bin/userdbctl ssh-authorized-keys %u --chain /usr/bin/othertool %u |
| AuthorizedKeysCommandUser root |
| …</programlisting> |
| |
| <para>The above will first query the userdb database for SSH keys, and then chain execute |
| <command>/usr/bin/othertool</command> to also be queried.</para> |
| </refsect1> |
| |
| <refsect1> |
| <title>Exit status</title> |
| |
| <para>On success, 0 is returned, a non-zero failure code otherwise.</para> |
| </refsect1> |
| |
| <xi:include href="common-variables.xml" /> |
| |
| <refsect1> |
| <title>See Also</title> |
| <para> |
| <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd-userdbd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd-homed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>, |
| <citerefentry project='man-pages'><refentrytitle>getent</refentrytitle><manvolnum>1</manvolnum></citerefentry> |
| </para> |
| </refsect1> |
| |
| </refentry> |
