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<!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="homectl" conditional='ENABLE_HOMED'
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>homectl</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>homectl</refentrytitle>
<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>homectl</refname>
<refpurpose>Create, remove, change or inspect home directories</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>homectl</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>homectl</command> may be used to create, remove, change or inspect a user's home
directory. It's primarily a command interfacing with
<citerefentry><refentrytitle>systemd-homed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
which manages home directories of users.</para>
<para>Home directories managed by <filename>systemd-homed.service</filename> are self-contained, and thus
include the user's full metadata record in the home's data storage itself, making them easy to migrate
between machines. In particular, a home directory describes a matching user record, and every user record
managed by <filename>systemd-homed.service</filename> also implies existence and encapsulation of a home
directory. The user account and home directory become the same concept.</para>
<para>The following backing storage mechanisms are supported:</para>
<itemizedlist>
<listitem><para>An individual LUKS2 encrypted loopback file for a user, stored in
<filename>/home/*.home</filename>. At login the file system contained in this files is mounted, after
the LUKS2 encrypted volume has been attached. The user's password is identical to the encryption
passphrase of the LUKS2 volume. Access to data without preceeding user authentication is thus not
possible, even for the system administrator. This storage mechanism provides the strongest data
security and is thus recommended.</para></listitem>
<listitem><para>Similar, but the LUKS2 encrypted file system is located on regular block device, such
as an USB storage stick. In this mode home directories and all data they include are nicely migratable
between machines, simply by plugging the USB stick into different systems at different
times.</para></listitem>
<listitem><para>An encrypted directory using <literal>fscrypt</literal> on file systems that support it
(at the moment this is primarily <literal>ext4</literal>), located in
<filename>/home/*.homedir</filename>. This mechanism also provides encryption, but substantially
weaker than LUKS2, as most file system metadata is unprotected. Moreover
it currently does not support changing user passwords once the home directory has been
created.</para></listitem>
<listitem><para>A <literal>btrfs</literal> subvolume for each user, also located in
<filename>/home/*.homedir</filename>. This provides no encryption, but good quota
support.</para></listitem>
<listitem><para>A regular directory for each user, also located in
<filename>/home/*.homedir</filename>. This provides no encryption, but is a suitable fallback
available on all machines, even where LUKS2, <literal>fscrypt</literal> or <literal>btrfs</literal>
support is not available.</para></listitem>
<listitem><para>An individual Windows file share (CIFS) for each user.</para></listitem>
</itemizedlist>
<para>Note that <filename>systemd-homed.service</filename> and <command>homectl</command> will not manage
"classic" UNIX user accounts as created with <citerefentry
project='man-pages'><refentrytitle>useradd</refentrytitle><manvolnum>8</manvolnum></citerefentry> or
similar tools. In particular, this functionality is not suitable for managing system users (i.e. users
with a UID below 1000) but is exclusive to regular ("human") users.</para>
<para>Note that users/home directories managed via <command>systemd-homed.service</command> do not show
up in <filename>/etc/passwd</filename> and similar files, they are synthesized via glibc NSS during
runtime. They are thus resolvable and may be enumerated via the <citerefentry
project='man-pages'><refentrytitle>getent</refentrytitle><manvolnum>1</manvolnum></citerefentry>
tool.</para>
<para>This tool interfaces directly with <filename>systemd-homed.service</filename>, and may execute
specific commands on the home directories it manages. Since every home directory managed that way also
defines a JSON user and group record these home directories may also be inspected and enumerated via
<citerefentry><refentrytitle>userdbctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
<para>Home directories managed by <filename>systemd-homed.service</filename> are usually in one of two
states, or in a transition state between them: when <literal>active</literal> they are unlocked and
mounted, and thus accessible to the system and its programs; when <literal>inactive</literal> they are
not mounted and thus not accessible. Activation happens automatically at login of the user and usually
can only complete after a password (or other authentication token) has been supplied. Deactivation
happens after the user fully logged out. A home directory remains active as long as the user is logged in
at least once, i.e. has at least one login session. When the user logs in a second time simultaneously
the home directory remains active. It is deactivated only after the last of the user's sessions
ends.</para>
</refsect1>
<refsect1>
<title>Options</title>
<para>The following general options are understood (further options that control the various properties
of user records managed by <filename>systemd-homed.service</filename> are documented further
down):</para>
<variablelist>
<varlistentry>
<term><option>--identity=</option><replaceable>FILE</replaceable></term>
<listitem><para>Read the user's JSON record from the specified file. If passed as
<literal>-</literal> reads the user record from standard input. The supplied JSON object must follow
the structure documented on <ulink url="https://systemd.io/USER_RECORDS">JSON User
Records</ulink>. This option may be used in conjunction with the <command>create</command> and
<command>update</command> commands (see below), where it allows configuring the user record in JSON
as-is, instead of setting the individual user record properties (see below).</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--json=</option><replaceable>FORMAT</replaceable></term>
<term><option>-J</option></term>
<listitem><para>Controls whether to output the user record in JSON format, if the
<command>inspect</command> command (see below) is used. Takes one of <literal>pretty</literal>,
<literal>short</literal> or <literal>off</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. If <literal>off</literal> (the
default) the user information is not shown in JSON format but in a friendly human readable formatting
instead. The <option>-J</option> option picks <literal>pretty</literal> when run interactively and
<literal>short</literal> otherwise.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--export-format=</option><replaceable>FORMAT</replaceable></term>
<term><option>-E</option></term>
<term><option>-EE</option></term>
<listitem><para>When used with the <command>inspect</command> verb in JSON mode (see above) may be
used to suppress certain aspects of the JSON user record on output. Specifically, if
<literal>stripped</literal> format is used the binding and runtime fields of the record are
removed. If <literal>minimal</literal> format is used the cryptographic signature is removed too. If
<literal>full</literal> format is used the full JSON record is shown (this is the default). This
option is useful for copying an existing user record to a different system in order to create a
similar user there with the same settings. Specifically: <command>homectl inspect -EE | ssh
root@othersystem homectl create -i-</command> may be used as simple command line for replicating a
user on another host. <option>-E</option> is equivalent to <option>-j --export-format=stripped</option>,
<option>-EE</option> to <option>-j --export-format=minimal</option>. Note that when replicating user
accounts user records acquired in <literal>stripped</literal> mode will retain the original
cryptographic signatures and thus may only be modified when the private key to update them is available
on the destination machine. When replicating users in <literal>minimal</literal> mode, the signature
is removed during the replication and thus the record will be implicitly signed with the key of the destination
machine and may be updated there without any private key replication.</para></listitem>
</varlistentry>
<xi:include href="user-system-options.xml" xpointer="host" />
<xi:include href="user-system-options.xml" xpointer="machine" />
<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="no-ask-password" />
<xi:include href="standard-options.xml" xpointer="help" />
<xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
</refsect1>
<refsect1>
<title>User Record Properties</title>
<para>The following options control various properties of the user records/home directories that
<filename>systemd-homed.service</filename> manages. These switches may be used in conjunction with the
<command>create</command> and <command>update</command> commands for configuring various aspects of the
home directory and the user account:</para>
<variablelist>
<varlistentry>
<term><option>--real-name=</option><replaceable>NAME</replaceable></term>
<term><option>-c</option> <replaceable>NAME</replaceable></term>
<listitem><para>The real name for the user. This corresponds with the GECOS field on classic UNIX NSS
records.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--realm=</option><replaceable>REALM</replaceable></term>
<listitem><para>The realm for the user. The realm associates a user with a specific organization or
installation, and allows distuingishing users of the same name defined in different contexts. The
realm can be any string that also qualifies as valid DNS domain name, and it is recommended to use
the organization's or installation's domain name for this purpose, but this is not enforced nor
required. On each system only a single user of the same name may exist, and if a user with the same
name and realm is seen it is assumed to refer to the same user while a user with the same name but
different realm is considered a different user. Note that this means that two users sharing the same
name but with distinct realms are not allowed on the same system. Assigning a realm to a user is
optional.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--email-address=</option><replaceable>EMAIL</replaceable></term>
<listitem><para>Takes an electronic mail address to associate with the user. On log-in the
<varname>$EMAIL</varname> environment variable is initialized from this value.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--location=</option><replaceable>TEXT</replaceable></term>
<listitem><para>Takes location specification for this user. This is free-form text, which might or
might not be usable by geo-location applications. Example: <option>--location="Berlin,
Germany"</option> or <option>--location="Basement, Room 3a"</option></para></listitem>
</varlistentry>
<varlistentry>
<term><option>--icon-name=</option><replaceable>ICON</replaceable></term>
<listitem><para>Takes an icon name to associate with the user, following the scheme defined by the <ulink
url="https://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html">Icon Naming
Specification</ulink>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--home-dir=</option><replaceable>PATH</replaceable></term>
<term><option>-d</option><replaceable>PATH</replaceable></term>
<listitem><para>Takes a path to use as home directory for the user. Note that this is the directory
the user's home directory is mounted to while the user is logged in. This is not where the user's
data is actually stored, see <option>--image-path=</option> for that. If not specified defaults to
<filename>/home/$USER</filename>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--uid=</option><replaceable>UID</replaceable></term>
<listitem><para>Takes a preferred numeric UNIX UID to assign this user. If a user is to be created
with the specified UID and it is already taken by a different user on the local system then creation
of the home directory is refused. Note though, if after creating the home directory it is used on a
different system and the configured UID is taken by another user there, then
<command>systemd-homed</command> may assign the user a different UID on that system. The specified
UID must be outside of the system user range. It is recommended to use the 60001…60513 UID range for
this purpose. If not specified the UID is automatically picked. When logging in and the home
directory is found to be owned by a UID not matching the user's assigned one the home directory and
all files and directories inside it will have their ownership changed automatically before login
completes.</para>
<para>Note that users managed by <command>systemd-homed</command> always have a matching group
associated with the same name as well as a GID matching the UID of the user. Thus, configuring the
GID separately is not permitted.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--member-of=</option><replaceable>GROUP</replaceable></term>
<term><option>-G</option> <replaceable>GROUP</replaceable></term>
<listitem><para>Takes a comma-separated list of auxiliary UNIX groups this user shall belong
to. Example: <option>--member-of=wheel</option> to provide the user with administrator
privileges. Note that <command>systemd-homed</command> does not manage any groups besides a group
matching the user in name and numeric UID/GID. Thus any groups listed here must be registered
independently, for example with <citerefentry
project='man-pages'><refentrytitle>groupadd</refentrytitle><manvolnum>8</manvolnum></citerefentry>. If
non-existant groups that are listed there are ignored. This option may be used more than once, in
which case all specified group lists are combined.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--skel=</option><replaceable>PATH</replaceable></term>
<listitem><para>Takes a file system path to a directory. Specifies the skeleton directory to
initialize the home directory with. All files and directories in the specified are copied into any
newly create home directory. If not specified defaults to
<filename>/etc/skel/</filename>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--shell=</option><replaceable>SHELL</replaceable></term>
<listitem><para>Takes a file system path. Specifies the shell binary to execute on terminal
logins. If not specified defaults to <filename>/bin/bash</filename>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--setenv=</option><replaceable>VARIABLE</replaceable>=<replaceable>VALUE</replaceable></term>
<listitem><para>Takes an environment variable assignment to set for all user processes. Note that a
number of other settings also result in environment variables to be set for the user, including
<option>--email=</option>, <option>--timezone=</option> and <option>--language=</option>. May be used
multiple times to set multiple environment variables.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--timezone=</option><replaceable>TIMEZONE</replaceable></term>
<listitem><para>Takes a timezone specification as string that sets the timezone for the specified
user. Expects a `tzdata` location string. When the user logs in the <varname>$TZ</varname>
environment variable is initialized from this setting. Example:
<option>--timezone=Europe/Amsterdam</option> will result in the environment variable
<literal>TZ=:Europe/Amsterdam</literal>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--language=</option><replaceable>LANG</replaceable></term>
<listitem><para>Takes a specifier indicating the preferred language of the user. The
<varname>$LANG</varname> environment variable is initialized from this value on login, and thus a
value suitable for this environment variable is accepted here, for example
<option>--language=de_DE.UTF8</option></para></listitem>
</varlistentry>
<varlistentry>
<term><option>--ssh-authorized-keys=</option><replaceable>KEYS</replaceable></term>
<listitem><para>Either takes a SSH authorized key line to associate with the user record or a
<literal>@</literal> character followed by a path to a file to read one or more such lines from. SSH
keys configured this way are made available to SSH to permit access to this home directory and user
record. This option may be used more than once to configure multiple SSH keys.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--pkcs11-token-uri=</option><replaceable>URI</replaceable></term>
<listitem><para>Takes an RFC 7512 PKCS#11 URI referencing a security token (e.g. YubiKey or PIV
smartcard) that shall be able to unlock the user account. The security token URI should reference a
security token with exactly one pair of X.509 certificate and private key. A random secret key is
then generated, encrypted with the public key of the X.509 certificate, and stored as part of the
user record. At login time it is decrypted with the PKCS#11 module and then used to unlock the
account and associated resources. See below for an example how to set up authentication with security
token.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--locked=</option><replaceable>BOOLEAN</replaceable></term>
<listitem><para>Takes a boolean argument. Specifies whether this user account shall be locked. If
true logins into this account are prohibited, if false (the default) they are permitted (of course,
only if authorization otherwise succeeds).</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--not-before=</option><replaceable>TIMESTAMP</replaceable></term>
<term><option>--not-after=</option><replaceable>TIMESTAMP</replaceable></term>
<listitem><para>These options take a timestamp string, in the format documented in
<citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry> and
configures points in time before and after logins into this account are not
permitted.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--rate-limit-interval=</option><replaceable>SECS</replaceable></term>
<term><option>--rate-limit-burst=</option><replaceable>NUMBER</replaceable></term>
<listitem><para>Configures a rate limit on authentication attempts for this user. If the user
attempts to authenticate more often than the specified number, on a specific system, within the
specified time interval authentication is refused until the time interval passes. Defaults to 10
times per 1min.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--password-hint=</option><replaceable>TEXT</replaceable></term>
<listitem><para>Takes a password hint to store alongside the user record. This string is stored
accessible only to privileged users and the user itself and may not be queried by other users.
Example: <option>--password-hint="My first pet's name"</option></para></listitem>
</varlistentry>
<varlistentry>
<term><option>--enforce-password-policy=</option><replaceable>BOOL</replaceable></term>
<term><option>-P</option></term>
<listitem><para>Takes a boolean argument. Configures whether to enforce the system's password policy
for this user, regarding quality and strength of selected passwords. Defaults to
on. <option>-P</option> is short for
<option>---enforce-password-policy=no</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--password-change-now=</option><replaceable>BOOL</replaceable></term>
<listitem><para>Takes a boolean argument. If true the user is asked to change their password on next
login.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--password-change-min=</option><replaceable>TIME</replaceable></term>
<term><option>--password-change-max=</option><replaceable>TIME</replaceable></term>
<term><option>--password-change-warn=</option><replaceable>TIME</replaceable></term>
<term><option>--password-change-inactive=</option><replaceable>TIME</replaceable></term>
<listitem><para>Each of these options takes a time span specification as argument (in the syntax
documented in
<citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>5</manvolnum></citerefentry>) and
configure various aspects of the user's password expiration policy. Specifically,
<option>--password-change-min=</option> configures how much time has to pass after changing the
password of the user until the password may be changed again. If the user tries to change their
password before this time passes the attempt is refused. <option>--password-change-max=</option>
configures how much time has to pass after the the password is changed until the password expires and
needs to be changed again. After this time passes any attempts to log in may only proceed after the
password is changed. <option>--password-change-warn=</option> specifies how much earlier than then
the time configured with <option>--password-change-max=</option> the user is warned at login to
change their password as it will expire soon. Finally <option>--password-change-inactive=</option>
configures the time which has to pass after the password as expired until the user is not permitted
to log in or change the password anymore. Note that these options only apply to password
authentication, and do not apply to other forms of authentication, for example PKCS#11-based security
token authentication.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--disk-size=</option><replaceable>BYTES</replaceable></term>
<listitem><para>Either takes a size in bytes as argument (possibly using the usual K, M, G, …
suffixes for 1024 base values), or a percentage value and configures the disk space to assign to the
user. If a percentage value is specified (i.e. the argument suffixed with <literal>%</literal>) it is
taken relative to the available disk space of the backing file system. If the LUKS2 backend is used
this configures the size of the loopback file and file system contained therein. For the other
storage backends configures disk quota using the filesystem's native quota logic, if available. If
not specified, defaults to 85% of the available disk space for the LUKS2 backend and to no quota for
the others.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--access-mode=</option><replaceable>MODE</replaceable></term>
<listitem><para>Takes a UNIX file access mode written in octal. Configures the access mode of the
home directory itself. Note that this is only used when the directory is first created, and the user
may change this any time afterwards. Example:
<option>--access-mode=0700</option></para></listitem>
</varlistentry>
<varlistentry>
<term><option>--umask=</option><replaceable>MASK</replaceable></term>
<listitem><para>Takes the access mode mask (in octal syntax) to apply to newly created files and
directories of the user ("umask"). If set this controls the initial umask set for all login sessions of
the user, possibly overriding the system's defaults.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--nice=</option><replaceable>NICE</replaceable></term>
<listitem><para>Takes the numeric scheduling priority ("nice level") to apply to the processes of the user at login
time. Takes a numeric value in the range -20 (highest priority) to 19 (lowest priority).</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--rlimit=</option><replaceable>LIMIT</replaceable>=<replaceable>VALUE</replaceable><optional>:<replaceable>VALUE</replaceable></optional></term>
<listitem><para>Allows configuration of resource limits for processes of this user, see <citerefentry
project='man-pages'><refentrytitle>getrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
for details. Takes a resource limit name (e.g. <literal>LIMIT_NOFILE</literal>) followed by an equal
sign, followed by a numeric limit. Optionally, separated by colon a second numeric limit may be
specified. If two are specified this refers to the soft and hard limits, respectively. If only one
limit is specified the setting sets both limits in one.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--tasks-max=</option><replaceable>TASKS</replaceable></term>
<listitem><para>Takes a non-zero unsigned integer as argument. Configures the maximum numer of tasks
(i.e. threads, where each process is at least one thread) the user may have at any given time. This
limit applies to all tasks forked off the user's sessions, even if they change user identity via
<citerefentry project='man-pages'><refentrytitle>su</refentrytitle><manvolnum>1</manvolnum></citerefentry>
or a similar tool. Use <option>--rlimit=LIMIT_NPROC=</option> to place a limit on the tasks actually
running under the UID of the user, thus excluding any child processes that might have changed user
identity. This controls the <varname>TasksMax=</varname> settting of the per-user systemd slice unit
<filename>user-$UID.slice</filename>. See
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for further details.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--memory-high=</option><replaceable>BYTES</replaceable></term>
<term><option>--memory-max=</option><replaceable>BYTES</replaceable></term>
<listitem><para>Set a limit on the memory a user may take up on a system at any given time in bytes
(the usual K, M, G, … suffixes are supported, to the base of 1024). This includes all memory used by
the user itself and all processes they forked off that changed user credentials. This controls the
<varname>MemoryHigh=</varname> and <varname>MemoryMax=</varname> settings of the per-user systemd
slice unit <filename>user-$UID.slice</filename>. See
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for further details.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--cpu-weight=</option><replaceable>WEIGHT</replaceable></term>
<term><option>--io-weight=</option><replaceable>WEIGHT</replaceable></term>
<listitem><para>Set a CPU and IO scheduling weights of the processes of the user, including those of
processes forked off by the user that changed user credentials. Takes a numeric value in the range
1…10000. This controls the <varname>CPUWeight=</varname> and <varname>IOWeight=</varname> settings of
the per-user systemd slice unit <filename>user-$UID.slice</filename>. See
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for further details.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--storage=</option><replaceable>STORAGE</replaceable></term>
<listitem><para>Selects the storage mechanism to use for this home directory. Takes one of
<literal>luks</literal>, <literal>fscrypt</literal>, <literal>directory</literal>,
<literal>subvolume</literal>, <literal>cifs</literal>. For details about these mechanisms, see
above. If a new home directory is created and the storage type is not specifically specified defaults
to <literal>luks</literal> if supported, <literal>subvolume</literal> as first fallback if supported,
and <literal>directory</literal> if not.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--image-path=</option><replaceable>PATH</replaceable></term>
<listitem><para>Takes a file system path. Configures where to place the user's home directory. When
LUKS2 storage is used refers to the path to the loopback file, otherwise to the path to the home
directory (which may be in <filename>/home/</filename> or any other accessible filesystem). When
unspecified defaults to <filename>/home/$USER.home</filename> when LUKS storage is used and
<filename>/home/$USER.homedir</filename> for the other storage mechanisms. Not defined for the
<literal>cifs</literal> storage mechanism. To use LUKS2 storage on a regular block device (for
example a USB stick) pass the path to the block device here. Specifying the path to a directory here
when using LUKS2 storage is not allowed. Similar, specifying the path to a regular file or device
node is not allowed if any of the other storage backends are used.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--fs-type=</option><replaceable>TYPE</replaceable></term>
<listitem><para>When LUKS2 storage is used configures the file system type to use inside the home
directory LUKS2 container. One of <literal>ext4</literal>, <literal>xfs</literal>,
<literal>btrfs</literal>. If not specified defaults to <literal>ext4</literal>. Note that
<literal>xfs</literal> is not recommended as its support for file system resizing is too
limited.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--luks-discard=</option><replaceable>BOOL</replaceable></term>
<listitem><para>When LUKS2 storage is used configures whether to enable the
<literal>discard</literal> feature of the file system. If enabled the file system on top of the LUKS2
volume will report empty block information to LUKS2 and the loopback file below, ensuring that empty
space in the home directory is returned to the backing file system below the LUKS2 volume, resulting
in a "sparse" loopback file. This option mostly defaults to off, since this permits over-committing
home directories which results in I/O errors if the underlying file system runs full while the upper
file system wants to allocate a block. Such I/O errors are generally not handled well by file systems
nor applications. When LUKS2 storage is used on top of regular block devices (instead of on top a
loopback file) the discard logic defaults to on.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--luks-cipher=</option><replaceable>CIPHER</replaceable></term>
<term><option>--luks-cipher-mode=</option><replaceable>MODE</replaceable></term>
<term><option>--luks-volume-key-size=</option><replaceable>BITS</replaceable></term>
<term><option>--luks-pbkdf-type=</option><replaceable>TYPE</replaceable></term>
<term><option>--luks-pbkdf-hash-algorithm=</option><replaceable>ALGORITHM</replaceable></term>
<term><option>--luks-pbkdf-time-cost=</option><replaceable>SECONDS</replaceable></term>
<term><option>--luks-pbkdf-memory-cost=</option><replaceable>BYTES</replaceable></term>
<term><option>--luks-pbkdf-parallel-threads=</option><replaceable>THREADS</replaceable></term>
<listitem><para>Configures various cryptographic parameters for the LUKS2 storage mechanism. See
<citerefentry
project='man-pages'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry>
for details on the specific attributes.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--nosuid=</option><replaceable>BOOL</replaceable></term>
<term><option>--nodev=</option><replaceable>BOOL</replaceable></term>
<term><option>--noexec=</option><replaceable>BOOL</replaceable></term>
<listitem><para>Configures the <literal>nosuid</literal>, <literal>nodev</literal> and
<literal>noexec</literal> mount options for the home directories. By default <literal>nodev</literal>
and <literal>nosuid</literal> are on, while <literal>noexec</literal> is off. For details about these
mount options see <citerefentry
project='man-pages'><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--cifs-domain=</option><replaceable>DOMAIN</replaceable></term>
<term><option>--cifs-user-name=</option><replaceable>USER</replaceable></term>
<term><option>--cifs-service=</option><replaceable>SERVICE</replaceable></term>
<listitem><para>Configures the Windows File Sharing (CIFS) domain and user to associate with the home
directory/user account, as well as the file share ("service") to mount as directory. The latter is used when
<literal>cifs</literal> storage is selected.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--stop-delay=</option><replaceable>SECS</replaceable></term>
<listitem><para>Configures the time the per-user service manager shall continue to run after the all
sessions of the user ended. The default is configured in
<citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> (for
home directories of LUKS2 storage located on removable media this defaults to 0 though). A longer
time makes sure quick, repetitive logins are more efficient as the user's service manager doesn't
have to be started every time.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--kill-processes=</option><replaceable>BOOL</replaceable></term>
<listitem><para>Configures whether to kill all processes of the user on logout. The default is
configured in
<citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--auto-login=</option><replaceable>BOOL</replaceable></term>
<listitem><para>Takes a boolean argument. Configures whether the graphical UI of the system should
automatically log this user in if possible. Defaults to off. If less or more than one user is marked
this way automatic login is disabled.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Commands</title>
<para>The following commands are understood:</para>
<variablelist>
<varlistentry>
<term><command>list</command></term>
<listitem><para>List all home directories (along with brief details) currently managed by
<filename>systemd-homed.service</filename>. This command is also executed if none is specified on the
command line. (Note that the list of users shown by this command does not include users managed by
other subsystems, such as system users or any traditional users listed in
<filename>/etc/passwd</filename>.)</para></listitem>
</varlistentry>
<varlistentry>
<term><command>activate</command> <replaceable>USER</replaceable> [<replaceable>USER…</replaceable>]</term>
<listitem><para>Activate one or more home directories. The home directories of each listed user will
be activated and made available under their mount points (typically in
<filename>/home/$USER</filename>). Note that any home activated this way stays active indefinitely,
until it is explicitly deactivated again (with <command>deactivate</command>, see below), or the user
logs in and out again and it thus is deactivated due to the automatic deactivation-on-logout
logic.</para>
<para>Activation of a home directory involves various operations that depend on the selected storage
mechanism. If the LUKS2 mechanism is used, this generally involves: inquiring the user for a
password, setting up a loopback device, validating and activating the LUKS2 volume, checking the file
system, mounting the file system, and potentiatlly changing the ownership of all included files to
the correct UID/GID.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>deactivate</command> <replaceable>USER</replaceable> [<replaceable>USER…</replaceable>]</term>
<listitem><para>Deactivate one or more home directories. This undoes the effect of
<command>activate</command>.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>inspect</command> <replaceable>USER</replaceable> [<replaceable>USER…</replaceable>]</term>
<listitem><para>Show various details about the specified home directories. This shows various
information about the home directory and its user account, including runtime data such as current
state, disk use and similar. Combine with <option>--json=</option> to show the detailed JSON user
record instead, possibly combined with <option>--export-format=</option> to suppress certain aspects
of the output.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>authenticate</command> <replaceable>USER</replaceable> [<replaceable>USER…</replaceable>]</term>
<listitem><para>Validate authentication credentials of a home directory. This queries the caller for
a password (or similar) and checks that it correctly unlocks the home directory. This leaves the home
directory in the state it is in, i.e. it leaves the home directory in inactive state if it was
inactive before, and in active state if it was active before.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>create</command> <replaceable>USER</replaceable></term>
<term><command>create</command> <option>--identity=</option><replaceable>PATH</replaceable> <optional><replaceable>USER</replaceable></optional></term>
<listitem><para>Create a new home directory/user account of the specified name. Use the various
user record property options (as documented above) to control various aspects of the home directory
and its user accounts.</para>
<para>The specified user name should follow the strict syntax described on <ulink
url="https://systemd.io/USER_NAMES">User/Group Name Syntax</ulink>.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>remove</command> <replaceable>USER</replaceable></term>
<listitem><para>Remove a home directory/user account. This will remove both the home directory's user
record and the home directory itself, and thus delete all files and directories owned by the
user.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>update</command> <replaceable>USER</replaceable></term>
<term><command>update</command> <option>--identity=</option><replaceable>PATH</replaceable> <optional><replaceable>USER</replaceable></optional></term>
<listitem><para>Update a home directory/user account. Use the various user record property options
(as documented above) to make changes to the account, or alternatively provide a full, updated JSON
user record via the <option>--identity=</option> option.</para>
<para>Note that changes to user records not signed by a cryptographic private key available locally
are not permitted, unless <option>--identity=</option> is used with a user record that is already
correctly signed by a recognized private key.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>passwd</command> <replaceable>USER</replaceable></term>
<listitem><para>Change the password of the specified home direcory/user account.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>resize</command> <replaceable>USER</replaceable> <replaceable>BYTES</replaceable></term>
<listitem><para>Change the disk space assigned to the specified home directory. If the LUKS2 storage
mechanism is used this will automatically resize the loopback file and the file system contained
within. Note that if <literal>ext4</literal> is used inside of the LUKS2 volume, it is necessary to
deactivate the home directory before shrinking it (i.e the user has to log out). Growing can be done
while the home directory is active. If <literal>xfs</literal> is used inside of the LUKS2 volume the
home directory may not be shrunk whatsoever. On all three of <literal>ext4</literal>,
<literal>xfs</literal> and <literal>btrfs</literal> the home directory may be grown while the user is
logged in, and on the latter also shrunk while the user is logged in. If the
<literal>subvolume</literal>, <literal>directory</literal>, <literal>fscrypt</literal> storage
mechanisms are used, resizing will change file system quota.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>lock</command> <replaceable>USER</replaceable></term>
<listitem><para>Temporarily suspend access to the user's home directory and remove any associated
cryptographic keys from memory. Any attempts to access the user's home directory will stall until the
home directory is unlocked again (i.e. re-authenticated). This functionality is primarily intended to
be used during system suspend to make sure the user's data cannot be accessed until the user
re-authenticates on resume. This operation is only defined for home directories that use the LUKS2
storage mechanism.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>unlock</command> <replaceable>USER</replaceable></term>
<listitem><para>Resume access to the user's home directory again, undoing the effect of
<command>lock</command> above. This requires authentication of the user, as the cryptographic keys
required for access to the home directory need to be reacquired.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>lock-all</command></term>
<listitem><para>Execute the <command>lock</command> command on all suitable home directories at
once. This operation is generally executed on system suspend (i.e. by <command>systemctl
suspend</command> and related commands), to ensure all active user's cryptographic keys for accessing
their home directories are removed from memory.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>with</command> <replaceable>USER</replaceable> <replaceable>COMMAND…</replaceable></term>
<listitem><para>Activate the specified user's home directory, run the specified command (under the
caller's identity, not the specified user's) and deactivate the home directory afterwards again
(unless the user is logged in otherwise). This command is useful for running privileged backup
scripts and such, but requires authentication with the user's credentials in order to be able to
unlock the user's home directory.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>On success, 0 is returned, a non-zero failure code otherwise.</para>
</refsect1>
<xi:include href="less-variables.xml" />
<refsect1>
<title>Examples</title>
<example>
<title>Create a user <literal>waldo</literal> in the administrator group <literal>wheel</literal>, and
assign 500 MiB disk space to them.</title>
<programlisting>homectl create waldo --real-name="Waldo McWaldo" -G wheel --disk-size=500M</programlisting>
</example>
<example>
<title>Create a user <literal>wally</literal> on a USB stick, and assign a maximum of 500 concurrent
tasks to them.</title>
<programlisting>homectl create wally --real-name="Wally McWally" --image-path=/dev/disk/by-id/usb-SanDisk_Ultra_Fit_476fff954b2b5c44-0:0 --tasks-max=500</programlisting>
</example>
<example>
<title>Change nice level of user <literal>odlaw</literal> to +5 and make sure the environment variable
<varname>$SOME</varname> is set to the string <literal>THING</literal> for them on login.</title>
<programlisting>homectl update odlaw --nice=5 --setenv=SOME=THING</programlisting>
</example>
<example>
<title>Set up authentication with a YubiKey security token:</title>
<programlisting># Clear the Yubikey from any old keys (careful!)
ykman piv reset
# Generate a new private/public key pair on the device, store the public key in 'pubkey.pem'.
ykman piv generate-key -a RSA2048 9d pubkey.pem
# Create a self-signed certificate from this public key, and store it on the device.
ykman piv generate-certificate --subject "Knobelei" 9d pubkey.pem
# We don't need the publibc key on disk anymore
rm pubkey.pem
# Check if the newly create key on the Yubikey shows up as token in PKCS#11. Have a look at the output, and
# copy the resulting token URI to the clipboard.
p11tool --list-tokens
# Allow the security token referenced by the determined PKCS#11 URI to unlock the account of user
# 'lafcadio'. (Replace the '…' by the URI from the clipboard.)
homectl update lafcadio --pkcs11-token-uri=…</programlisting>
</example>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-homed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>userdbctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>useradd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='man-pages'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>