1HOMECTL(1) homectl HOMECTL(1)
2
6 homectl - Create, remove, change or inspect home directories
7
9 homectl [OPTIONS...] {COMMAND} [NAME...]
10
12 homectl may be used to create, remove, change or inspect a user's home
13 directory. It's primarily a command interfacing with systemd-
14 homed.service(8) which manages home directories of users.
15 Home directories managed by systemd-homed.service are self-contained,
17 and thus include the user's full metadata record in the home's data
18 storage itself, making them easy to migrate between machines. In
19 particular, a home directory describes a matching user record, and
20 every user record managed by systemd-homed.service also implies
21 existence and encapsulation of a home directory. The user account and
22 home directory become the same concept.
23 The following backing storage mechanisms are supported:
25 • An individual LUKS2 encrypted loopback file for a user, stored in
27 /home/*.home. At login the file system contained in this files is
28 mounted, after the LUKS2 encrypted volume has been attached. The
29 user's password is identical to the encryption passphrase of the
30 LUKS2 volume. Access to data without preceding user authentication
31 is thus not possible, even for the system administrator. This
32 storage mechanism provides the strongest data security and is thus
33 recommended.
34 • Similar, but the LUKS2 encrypted file system is located on regular
36 block device, such as an USB storage stick. In this mode home
37 directories and all data they include are nicely migratable between
38 machines, simply by plugging the USB stick into different systems
39 at different times.
40 • An encrypted directory using "fscrypt" on file systems that support
42 it (at the moment this is primarily "ext4"), located in
43 /home/*.homedir. This mechanism also provides encryption, but
44 substantially weaker than LUKS2, as most file system metadata is
45 unprotected. Moreover it currently does not support changing user
46 passwords once the home directory has been created.
47 • A "btrfs" subvolume for each user, also located in /home/*.homedir.
49 This provides no encryption, but good quota support.
50 • A regular directory for each user, also located in /home/*.homedir.
52 This provides no encryption, but is a suitable fallback available
53 on all machines, even where LUKS2, "fscrypt" or "btrfs" support is
54 not available.
55 • An individual Windows file share (CIFS) for each user.
57 Note that systemd-homed.service and homectl will not manage "classic"
59 UNIX user accounts as created with useradd(8) or similar tools. In
60 particular, this functionality is not suitable for managing system
61 users (i.e. users with a UID below 1000) but is exclusive to regular
62 ("human") users.
63 Note that users/home directories managed via systemd-homed.service do
65 not show up in /etc/passwd and similar files, they are synthesized via
66 glibc NSS during runtime. They are thus resolvable and may be
67 enumerated via the getent(1) tool.
68 This tool interfaces directly with systemd-homed.service, and may
70 execute specific commands on the home directories it manages. Since
71 every home directory managed that way also defines a JSON user and
72 group record these home directories may also be inspected and
73 enumerated via userdbctl(1).
74 Home directories managed by systemd-homed.service are usually in one of
76 two states, or in a transition state between them: when "active" they
77 are unlocked and mounted, and thus accessible to the system and its
78 programs; when "inactive" they are not mounted and thus not accessible.
79 Activation happens automatically at login of the user and usually can
80 only complete after a password (or other authentication token) has been
81 supplied. Deactivation happens after the user fully logged out. A home
82 directory remains active as long as the user is logged in at least
83 once, i.e. has at least one login session. When the user logs in a
84 second time simultaneously the home directory remains active. It is
85 deactivated only after the last of the user's sessions ends.
86
88 The following general options are understood (further options that
89 control the various properties of user records managed by
90 systemd-homed.service are documented further down):
91 --identity=FILE
93 Read the user's JSON record from the specified file. If passed as
94 "-" read the user record from standard input. The supplied JSON
95 object must follow the structure documented in JSON User
96 Records[1]. This option may be used in conjunction with the create
97 and update commands (see below), where it allows configuring the
98 user record in JSON as-is, instead of setting the individual user
99 record properties (see below).
100 --json=FORMAT, -J
102 Controls whether to output the user record in JSON format, if the
103 inspect command (see below) is used. Takes one of "pretty", "short"
104 or "off". If "pretty" human-friendly whitespace and newlines are
105 inserted in the output to make the JSON data more readable. If
106 "short" all superfluous whitespace is suppressed. If "off" (the
107 default) the user information is not shown in JSON format but in a
108 friendly human readable formatting instead. The -J option picks
109 "pretty" when run interactively and "short" otherwise.
110 --export-format=FORMAT, -E, -EE
112 When used with the inspect verb in JSON mode (see above) may be
113 used to suppress certain aspects of the JSON user record on output.
114 Specifically, if "stripped" format is used the binding and runtime
115 fields of the record are removed. If "minimal" format is used the
116 cryptographic signature is removed too. If "full" format is used
117 the full JSON record is shown (this is the default). This option is
118 useful for copying an existing user record to a different system in
119 order to create a similar user there with the same settings.
120 Specifically: homectl inspect -EE | ssh root@othersystem homectl
121 create -i- may be used as simple command line for replicating a
122 user on another host. -E is equivalent to -j
123 --export-format=stripped, -EE to -j --export-format=minimal. Note
124 that when replicating user accounts user records acquired in
125 "stripped" mode will retain the original cryptographic signatures
126 and thus may only be modified when the private key to update them
127 is available on the destination machine. When replicating users in
128 "minimal" mode, the signature is removed during the replication and
129 thus the record will be implicitly signed with the key of the
130 destination machine and may be updated there without any private
131 key replication.
132 -H, --host=
134 Execute the operation remotely. Specify a hostname, or a username
135 and hostname separated by "@", to connect to. The hostname may
136 optionally be suffixed by a port ssh is listening on, separated by
137 ":", and then a container name, separated by "/", which connects
138 directly to a specific container on the specified host. This will
139 use SSH to talk to the remote machine manager instance. Container
140 names may be enumerated with machinectl -H HOST. Put IPv6 addresses
141 in brackets.
142 -M, --machine=
144 Execute operation on a local container. Specify a container name to
145 connect to, optionally prefixed by a user name to connect as and a
146 separating "@" character. If the special string ".host" is used in
147 place of the container name, a connection to the local system is
148 made (which is useful to connect to a specific user's user bus:
149 "--user --machine=lennart@.host"). If the "@" syntax is not used,
150 the connection is made as root user. If the "@" syntax is used
151 either the left hand side or the right hand side may be omitted
152 (but not both) in which case the local user name and ".host" are
153 implied.
154 --no-pager
156 Do not pipe output into a pager.
157 --no-legend
159 Do not print the legend, i.e. column headers and the footer with
160 hints.
161 --no-ask-password
163 Do not query the user for authentication for privileged operations.
164 -h, --help
166 Print a short help text and exit.
167 --version
169 Print a short version string and exit.
170
172 The following options control various properties of the user
173 records/home directories that systemd-homed.service manages. These
174 switches may be used in conjunction with the create and update commands
175 for configuring various aspects of the home directory and the user
176 account:
177 --real-name=NAME, -c NAME
179 The real name for the user. This corresponds with the GECOS field
180 on classic UNIX NSS records.
181 --realm=REALM
183 The realm for the user. The realm associates a user with a specific
184 organization or installation, and allows distinguishing users of
185 the same name defined in different contexts. The realm can be any
186 string that also qualifies as valid DNS domain name, and it is
187 recommended to use the organization's or installation's domain name
188 for this purpose, but this is not enforced nor required. On each
189 system only a single user of the same name may exist, and if a user
190 with the same name and realm is seen it is assumed to refer to the
191 same user while a user with the same name but different realm is
192 considered a different user. Note that this means that two users
193 sharing the same name but with distinct realms are not allowed on
194 the same system. Assigning a realm to a user is optional.
195 --email-address=EMAIL
197 Takes an electronic mail address to associate with the user. On
198 log-in the $EMAIL environment variable is initialized from this
199 value.
200 --location=TEXT
202 Takes location specification for this user. This is free-form text,
203 which might or might not be usable by geo-location applications.
204 Example: --location="Berlin, Germany" or --location="Basement, Room
205 3a"
206 --icon-name=ICON
208 Takes an icon name to associate with the user, following the scheme
209 defined by the Icon Naming Specification[2].
210 --home-dir=PATH, -dPATH
212 Takes a path to use as home directory for the user. Note that this
213 is the directory the user's home directory is mounted to while the
214 user is logged in. This is not where the user's data is actually
215 stored, see --image-path= for that. If not specified defaults to
216 /home/$USER.
217 --uid=UID
219 Takes a preferred numeric UNIX UID to assign this user. If a user
220 is to be created with the specified UID and it is already taken by
221 a different user on the local system then creation of the home
222 directory is refused. Note though, if after creating the home
223 directory it is used on a different system and the configured UID
224 is taken by another user there, then systemd-homed may assign the
225 user a different UID on that system. The specified UID must be
226 outside of the system user range. It is recommended to use the
227 60001...60513 UID range for this purpose. If not specified, the UID
228 is automatically picked. If the home directory is found to be owned
229 by a different UID when logging in, the home directory and
230 everything underneath it will have its ownership changed
231 automatically before login completes.
232 Note that users managed by systemd-homed always have a matching
234 group associated with the same name as well as a GID matching the
235 UID of the user. Thus, configuring the GID separately is not
236 permitted.
237 --member-of=GROUP, -G GROUP
239 Takes a comma-separated list of auxiliary UNIX groups this user
240 shall belong to. Example: --member-of=wheel to provide the user
241 with administrator privileges. Note that systemd-homed does not
242 manage any groups besides a group matching the user in name and
243 numeric UID/GID. Thus any groups listed here must be registered
244 independently, for example with groupadd(8). Any non-existent
245 groups are ignored. This option may be used more than once, in
246 which case all specified group lists are combined. If the user is
247 currently a member of a group which is not listed, the user will be
248 removed from the group.
249 --skel=PATH
251 Takes a file system path to a directory. Specifies the skeleton
252 directory to initialize the home directory with. All files and
253 directories in the specified path are copied into any newly create
254 home directory. If not specified defaults to /etc/skel/.
255 --shell=SHELL
257 Takes a file system path. Specifies the shell binary to execute on
258 terminal logins. If not specified defaults to /bin/bash.
259 --setenv=VARIABLE=VALUE
261 Takes an environment variable assignment to set for all user
262 processes. Note that a number of other settings also result in
263 environment variables to be set for the user, including --email=,
264 --timezone= and --language=. May be used multiple times to set
265 multiple environment variables.
266 --timezone=TIMEZONE
268 Takes a time zone location name that sets the timezone for the
269 specified user. When the user logs in the $TZ environment variable
270 is initialized from this setting. Example:
271 --timezone=Europe/Amsterdam will result in the environment variable
272 "TZ=:Europe/Amsterdam". (":" is used intentionally as part of the
273 timezone specification, see tzset(3).)
274 --language=LANG
276 Takes a specifier indicating the preferred language of the user.
277 The $LANG environment variable is initialized from this value on
278 login, and thus a value suitable for this environment variable is
279 accepted here, for example --language=de_DE.UTF8.
280 --ssh-authorized-keys=KEYS
282 Either takes a SSH authorized key line to associate with the user
283 record or a "@" character followed by a path to a file to read one
284 or more such lines from. SSH keys configured this way are made
285 available to SSH to permit access to this home directory and user
286 record. This option may be used more than once to configure
287 multiple SSH keys.
288 --pkcs11-token-uri=URI
290 Takes an RFC 7512 PKCS#11 URI referencing a security token (e.g.
291 YubiKey or PIV smartcard) that shall be able to unlock the user
292 account. The security token URI should reference a security token
293 with exactly one pair of X.509 certificate and private key. A
294 random secret key is then generated, encrypted with the public key
295 of the X.509 certificate, and stored as part of the user record. At
296 login time it is decrypted with the PKCS#11 module and then used to
297 unlock the account and associated resources. See below for an
298 example how to set up authentication with a security token.
299 Instead of a valid PKCS#11 URI, the special strings "list" and
301 "auto" may be specified. If "list" is passed, a brief table of
302 suitable, currently plugged in PKCS#11 hardware tokens is shown,
303 along with their URIs. If "auto" is passed, a suitable PKCS#11
304 hardware token is automatically selected (this operation will fail
305 if there isn't exactly one suitable token discovered). The latter
306 is a useful shortcut for the most common case where a single
307 PKCS#11 hardware token is plugged in.
308 Note that many hardware security tokens implement both PKCS#11/PIV
310 and FIDO2 with the "hmac-secret" extension (for example: the
311 YubiKey 5 series), as supported with the --fido2-device= option
312 below. Both mechanisms are similarly powerful, though FIDO2 is the
313 more modern technology. PKCS#11/PIV tokens have the benefit of
314 being recognizable before authentication and hence can be used for
315 implying the user identity to use for logging in, which FIDO2 does
316 not allow. PKCS#11/PIV devices generally require initialization
317 (i.e. storing a private/public key pair on them, see example below)
318 before they can be used; FIDO2 security tokens generally do not
319 required that, and work out of the box.
320 --fido2-device=PATH
322 Takes a path to a Linux "hidraw" device (e.g. /dev/hidraw1),
323 referring to a FIDO2 security token implementing the "hmac-secret"
324 extension that shall be able to unlock the user account. A random
325 salt value is generated on the host and passed to the FIDO2 device,
326 which calculates a HMAC hash of the salt using an internal secret
327 key. The result is then used as the key to unlock the user account.
328 The random salt is included in the user record, so that whenever
329 authentication is needed it can be passed to the FIDO2 token again.
330 Instead of a valid path to a FIDO2 "hidraw" device the special
332 strings "list" and "auto" may be specified. If "list" is passed, a
333 brief table of suitable discovered FIDO2 devices is shown. If
334 "auto" is passed, a suitable FIDO2 token is automatically selected,
335 if exactly one is discovered. The latter is a useful shortcut for
336 the most common case where a single FIDO2 hardware token is plugged
337 in.
338 Note that FIDO2 devices suitable for this option must implement the
340 "hmac-secret" extension. Most current devices (such as the YubiKey
341 5 series) do. If the extension is not implemented the device cannot
342 be used for unlocking home directories.
343 Note that many hardware security tokens implement both FIDO2 and
345 PKCS#11/PIV (and thus may be used with either --fido2-device= or
346 --pkcs11-token-uri=), for a discussion see above.
347 --recovery-key=BOOL
349 Accepts a boolean argument. If enabled a recovery key is configured
350 for the account. A recovery key is a computer generated access key
351 that may be used to regain access to an account if the password has
352 been forgotten or the authentication token lost. The key is
353 generated and shown on screen, and should be printed or otherwise
354 transferred to a secure location. A recovery key may be entered
355 instead of a regular password to unlock the account.
356 --locked=BOOLEAN
358 Takes a boolean argument. Specifies whether this user account shall
359 be locked. If true logins into this account are prohibited, if
360 false (the default) they are permitted (of course, only if
361 authorization otherwise succeeds).
362 --not-before=TIMESTAMP, --not-after=TIMESTAMP
364 These options take a timestamp string, in the format documented in
365 systemd.time(7) and configures points in time before and after
366 logins into this account are not permitted.
367 --rate-limit-interval=SECS, --rate-limit-burst=NUMBER
369 Configures a rate limit on authentication attempts for this user.
370 If the user attempts to authenticate more often than the specified
371 number, on a specific system, within the specified time interval
372 authentication is refused until the time interval passes. Defaults
373 to 10 times per 1min.
374 --password-hint=TEXT
376 Takes a password hint to store alongside the user record. This
377 string is stored accessible only to privileged users and the user
378 itself and may not be queried by other users. Example:
379 --password-hint="My first pet's name".
380 --enforce-password-policy=BOOL, -P
382 Takes a boolean argument. Configures whether to enforce the
383 system's password policy for this user, regarding quality and
384 strength of selected passwords. Defaults to on. -P is short for
385 ---enforce-password-policy=no.
386 --password-change-now=BOOL
388 Takes a boolean argument. If true the user is asked to change their
389 password on next login.
390 --password-change-min=TIME, --password-change-max=TIME,
392 --password-change-warn=TIME, --password-change-inactive=TIME
393 Each of these options takes a time span specification as argument
394 (in the syntax documented in systemd.time(7)) and configures
395 various aspects of the user's password expiration policy.
396 Specifically, --password-change-min= configures how much time has
397 to pass after changing the password of the user until the password
398 may be changed again. If the user tries to change their password
399 before this time passes the attempt is refused.
400 --password-change-max= configures how soon after it has been
401 changed the password expires and needs to be changed again. After
402 this time passes logging in may only proceed after the password is
403 changed. --password-change-warn= specifies how much earlier than
404 then the time configured with --password-change-max= the user is
405 warned at login to change their password as it will expire soon.
406 Finally --password-change-inactive= configures the time which has
407 to pass after the password as expired until the user is not
408 permitted to log in or change the password anymore. Note that these
409 options only apply to password authentication, and do not apply to
410 other forms of authentication, for example PKCS#11-based security
411 token authentication.
412 --disk-size=BYTES
414 Either takes a size in bytes as argument (possibly using the usual
415 K, M, G, ... suffixes for 1024 base values), or a percentage value
416 and configures the disk space to assign to the user. If a
417 percentage value is specified (i.e. the argument suffixed with "%")
418 it is taken relative to the available disk space of the backing
419 file system. If the LUKS2 backend is used this configures the size
420 of the loopback file and file system contained therein. For the
421 other storage backends configures disk quota using the filesystem's
422 native quota logic, if available. If not specified, defaults to 85%
423 of the available disk space for the LUKS2 backend and to no quota
424 for the others.
425 --access-mode=MODE
427 Takes a UNIX file access mode written in octal. Configures the
428 access mode of the home directory itself. Note that this is only
429 used when the directory is first created, and the user may change
430 this any time afterwards. Example: --access-mode=0700
431 --umask=MASK
433 Takes the access mode mask (in octal syntax) to apply to newly
434 created files and directories of the user ("umask"). If set this
435 controls the initial umask set for all login sessions of the user,
436 possibly overriding the system's defaults.
437 --nice=NICE
439 Takes the numeric scheduling priority ("nice level") to apply to
440 the processes of the user at login time. Takes a numeric value in
441 the range -20 (highest priority) to 19 (lowest priority).
442 --rlimit=LIMIT=VALUE[:VALUE]
444 Allows configuration of resource limits for processes of this user,
445 see getrlimit(2) for details. Takes a resource limit name (e.g.
446 "LIMIT_NOFILE") followed by an equal sign, followed by a numeric
447 limit. Optionally, separated by colon a second numeric limit may be
448 specified. If two are specified this refers to the soft and hard
449 limits, respectively. If only one limit is specified the setting
450 sets both limits in one.
451 --tasks-max=TASKS
453 Takes a non-zero unsigned integer as argument. Configures the
454 maximum number of tasks (i.e. threads, where each process is at
455 least one thread) the user may have at any given time. This limit
456 applies to all tasks forked off the user's sessions, even if they
457 change user identity via su(1) or a similar tool. Use
458 --rlimit=LIMIT_NPROC= to place a limit on the tasks actually
459 running under the UID of the user, thus excluding any child
460 processes that might have changed user identity. This controls the
461 TasksMax= setting of the per-user systemd slice unit
462 user-$UID.slice. See systemd.resource-control(5) for further
463 details.
464 --memory-high=BYTES, --memory-max=BYTES
466 Set a limit on the memory a user may take up on a system at any
467 given time in bytes (the usual K, M, G, ... suffixes are supported,
468 to the base of 1024). This includes all memory used by the user
469 itself and all processes they forked off that changed user
470 credentials. This controls the MemoryHigh= and MemoryMax= settings
471 of the per-user systemd slice unit user-$UID.slice. See
472 systemd.resource-control(5) for further details.
473 --cpu-weight=WEIGHT, --io-weight=WEIGHT
475 Set CPU and IO scheduling weights of the processes of the user,
476 including those of processes forked off by the user that changed
477 user credentials. Takes a numeric value in the range 1...10000.
478 This controls the CPUWeight= and IOWeight= settings of the per-user
479 systemd slice unit user-$UID.slice. See systemd.resource-control(5)
480 for further details.
481 --storage=STORAGE
483 Selects the storage mechanism to use for this home directory. Takes
484 one of "luks", "fscrypt", "directory", "subvolume", "cifs". For
485 details about these mechanisms, see above. If a new home directory
486 is created and the storage type is not specifically specified,
487 homed.conf(5) defines which default storage to use.
488 --image-path=PATH
490 Takes a file system path. Configures where to place the user's home
491 directory. When LUKS2 storage is used refers to the path to the
492 loopback file, otherwise to the path to the home directory (which
493 may be in /home/ or any other accessible filesystem). When
494 unspecified defaults to /home/$USER.home when LUKS storage is used
495 and /home/$USER.homedir for the other storage mechanisms. Not
496 defined for the "cifs" storage mechanism. To use LUKS2 storage on a
497 regular block device (for example a USB stick) pass the path to the
498 block device here. Specifying the path to a directory here when
499 using LUKS2 storage is not allowed. Similar, specifying the path to
500 a regular file or device node is not allowed if any of the other
501 storage backends are used.
502 --fs-type=TYPE
504 When LUKS2 storage is used configures the file system type to use
505 inside the home directory LUKS2 container. One of "btrfs", "ext4",
506 "xfs". If not specified homed.conf(5) defines which default file
507 system type to use. Note that "xfs" is not recommended as its
508 support for file system resizing is too limited.
509 --luks-discard=BOOL
511 When LUKS2 storage is used configures whether to enable the
512 "discard" feature of the file system. If enabled the file system on
513 top of the LUKS2 volume will report empty block information to
514 LUKS2 and the loopback file below, ensuring that empty space in the
515 home directory is returned to the backing file system below the
516 LUKS2 volume, resulting in a "sparse" loopback file. This option
517 mostly defaults to off, since this permits over-committing home
518 directories which results in I/O errors if the underlying file
519 system runs full while the upper file system wants to allocate a
520 block. Such I/O errors are generally not handled well by file
521 systems nor applications. When LUKS2 storage is used on top of
522 regular block devices (instead of on top a loopback file) the
523 discard logic defaults to on.
524 --luks-offline-discard=BOOL
526 Similar to --luks-discard=, controls the trimming of the file
527 system. However, while --luks-discard= controls what happens when
528 the home directory is active, --luks-offline-discard= controls what
529 happens when it becomes inactive, i.e. whether to trim/allocate the
530 storage when deactivating the home directory. This option defaults
531 to on, to ensure disk space is minimized while a user is not logged
532 in.
533 --luks-cipher=CIPHER, --luks-cipher-mode=MODE,
535 --luks-volume-key-size=BITS, --luks-pbkdf-type=TYPE,
536 --luks-pbkdf-hash-algorithm=ALGORITHM, --luks-pbkdf-time-cost=SECONDS,
537 --luks-pbkdf-memory-cost=BYTES, --luks-pbkdf-parallel-threads=THREADS
538 Configures various cryptographic parameters for the LUKS2 storage
539 mechanism. See cryptsetup(8) for details on the specific
540 attributes.
541 --nosuid=BOOL, --nodev=BOOL, --noexec=BOOL
543 Configures the "nosuid", "nodev" and "noexec" mount options for the
544 home directories. By default "nodev" and "nosuid" are on, while
545 "noexec" is off. For details about these mount options see
546 mount(8).
547 --cifs-domain=DOMAIN, --cifs-user-name=USER, --cifs-service=SERVICE
549 Configures the Windows File Sharing (CIFS) domain and user to
550 associate with the home directory/user account, as well as the file
551 share ("service") to mount as directory. The latter is used when
552 "cifs" storage is selected.
553 --stop-delay=SECS
555 Configures the time the per-user service manager shall continue to
556 run after the all sessions of the user ended. The default is
557 configured in logind.conf(5) (for home directories of LUKS2 storage
558 located on removable media this defaults to 0 though). A longer
559 time makes sure quick, repetitive logins are more efficient as the
560 user's service manager doesn't have to be started every time.
561 --kill-processes=BOOL
563 Configures whether to kill all processes of the user on logout. The
564 default is configured in logind.conf(5).
565 --auto-login=BOOL
567 Takes a boolean argument. Configures whether the graphical UI of
568 the system should automatically log this user in if possible.
569 Defaults to off. If less or more than one user is marked this way
570 automatic login is disabled.
571
573 The following commands are understood:
574 list
576 List all home directories (along with brief details) currently
577 managed by systemd-homed.service. This command is also executed if
578 none is specified on the command line. (Note that the list of users
579 shown by this command does not include users managed by other
580 subsystems, such as system users or any traditional users listed in
581 /etc/passwd.)
582 activate USER [USER...]
584 Activate one or more home directories. The home directories of each
585 listed user will be activated and made available under their mount
586 points (typically in /home/$USER). Note that any home activated
587 this way stays active indefinitely, until it is explicitly
588 deactivated again (with deactivate, see below), or the user logs in
589 and out again and it thus is deactivated due to the automatic
590 deactivation-on-logout logic.
591 Activation of a home directory involves various operations that
593 depend on the selected storage mechanism. If the LUKS2 mechanism is
594 used, this generally involves: inquiring the user for a password,
595 setting up a loopback device, validating and activating the LUKS2
596 volume, checking the file system, mounting the file system, and
597 potentially changing the ownership of all included files to the
598 correct UID/GID.
599 deactivate USER [USER...]
601 Deactivate one or more home directories. This undoes the effect of
602 activate.
603 inspect USER [USER...]
605 Show various details about the specified home directories. This
606 shows various information about the home directory and its user
607 account, including runtime data such as current state, disk use and
608 similar. Combine with --json= to show the detailed JSON user record
609 instead, possibly combined with --export-format= to suppress
610 certain aspects of the output.
611 authenticate USER [USER...]
613 Validate authentication credentials of a home directory. This
614 queries the caller for a password (or similar) and checks that it
615 correctly unlocks the home directory. This leaves the home
616 directory in the state it is in, i.e. it leaves the home directory
617 in inactive state if it was inactive before, and in active state if
618 it was active before.
619 create USER, create --identity=PATH [USER]
621 Create a new home directory/user account of the specified name. Use
622 the various user record property options (as documented above) to
623 control various aspects of the home directory and its user
624 accounts.
625 The specified user name should follow the strict syntax described
627 on User/Group Name Syntax[3].
628 remove USER
630 Remove a home directory/user account. This will remove both the
631 home directory's user record and the home directory itself, and
632 thus delete all files and directories owned by the user.
633 update USER, update --identity=PATH [USER]
635 Update a home directory/user account. Use the various user record
636 property options (as documented above) to make changes to the
637 account, or alternatively provide a full, updated JSON user record
638 via the --identity= option.
639 Note that changes to user records not signed by a cryptographic
641 private key available locally are not permitted, unless --identity=
642 is used with a user record that is already correctly signed by a
643 recognized private key.
644 passwd USER
646 Change the password of the specified home directory/user account.
647 resize USER BYTES
649 Change the disk space assigned to the specified home directory. If
650 the LUKS2 storage mechanism is used this will automatically resize
651 the loopback file and the file system contained within. Note that
652 if "ext4" is used inside of the LUKS2 volume, it is necessary to
653 deactivate the home directory before shrinking it (i.e the user has
654 to log out). Growing can be done while the home directory is
655 active. If "xfs" is used inside of the LUKS2 volume the home
656 directory may not be shrunk whatsoever. On all three of "ext4",
657 "xfs" and "btrfs" the home directory may be grown while the user is
658 logged in, and on the latter also shrunk while the user is logged
659 in. If the "subvolume", "directory", "fscrypt" storage mechanisms
660 are used, resizing will change file system quota.
661 lock USER
663 Temporarily suspend access to the user's home directory and remove
664 any associated cryptographic keys from memory. Any attempts to
665 access the user's home directory will stall until the home
666 directory is unlocked again (i.e. re-authenticated). This
667 functionality is primarily intended to be used during system
668 suspend to make sure the user's data cannot be accessed until the
669 user re-authenticates on resume. This operation is only defined for
670 home directories that use the LUKS2 storage mechanism.
671 unlock USER
673 Resume access to the user's home directory again, undoing the
674 effect of lock above. This requires authentication of the user, as
675 the cryptographic keys required for access to the home directory
676 need to be reacquired.
677 lock-all
679 Execute the lock command on all suitable home directories at once.
680 This operation is generally executed on system suspend (i.e. by
681 systemctl suspend and related commands), to ensure all active
682 user's cryptographic keys for accessing their home directories are
683 removed from memory.
684 deactivate-all
686 Execute the deactivate command on all active home directories at
687 once. This operation is generally executed on system shut down
688 (i.e. by systemctl poweroff and related commands), to ensure all
689 active user's home directories are fully deactivated before /home/
690 and related file systems are unmounted.
691 with USER COMMAND...
693 Activate the specified user's home directory, run the specified
694 command (under the caller's identity, not the specified user's) and
695 deactivate the home directory afterwards again (unless the user is
696 logged in otherwise). This command is useful for running privileged
697 backup scripts and such, but requires authentication with the
698 user's credentials in order to be able to unlock the user's home
699 directory.
700
702 On success, 0 is returned, a non-zero failure code otherwise.
703 When a command is invoked with with, the exit status of the child is
705 propagated. Effectively, homectl will exit without error if the command
706 is successfully invoked and finishes successfully.
707
709 $SYSTEMD_LOG_LEVEL
710 The maximum log level of emitted messages (messages with a higher
711 log level, i.e. less important ones, will be suppressed). Either
712 one of (in order of decreasing importance) emerg, alert, crit, err,
713 warning, notice, info, debug, or an integer in the range 0...7. See
714 syslog(3) for more information.
715 $SYSTEMD_LOG_COLOR
717 A boolean. If true, messages written to the tty will be colored
718 according to priority.
719 This setting is only useful when messages are written directly to
721 the terminal, because journalctl(1) and other tools that display
722 logs will color messages based on the log level on their own.
723 $SYSTEMD_LOG_TIME
725 A boolean. If true, log messages will be prefixed with a timestamp.
726 This setting is only useful when messages are written directly to
728 the terminal or a file, because journalctl(1) and other tools that
729 display logs will attach timestamps based on the entry metadata on
730 their own.
731 $SYSTEMD_LOG_LOCATION
733 A boolean. If true, messages will be prefixed with a filename and
734 line number in the source code where the message originates.
735 Note that the log location is often attached as metadata to journal
737 entries anyway. Including it directly in the message text can
738 nevertheless be convenient when debugging programs.
739 $SYSTEMD_LOG_TID
741 A boolean. If true, messages will be prefixed with the current
742 numerical thread ID (TID).
743 Note that the this information is attached as metadata to journal
745 entries anyway. Including it directly in the message text can
746 nevertheless be convenient when debugging programs.
747 $SYSTEMD_LOG_TARGET
749 The destination for log messages. One of console (log to the
750 attached tty), console-prefixed (log to the attached tty but with
751 prefixes encoding the log level and "facility", see syslog(3), kmsg
752 (log to the kernel circular log buffer), journal (log to the
753 journal), journal-or-kmsg (log to the journal if available, and to
754 kmsg otherwise), auto (determine the appropriate log target
755 automatically, the default), null (disable log output).
756 $SYSTEMD_PAGER
758 Pager to use when --no-pager is not given; overrides $PAGER. If
759 neither $SYSTEMD_PAGER nor $PAGER are set, a set of well-known
760 pager implementations are tried in turn, including less(1) and
761 more(1), until one is found. If no pager implementation is
762 discovered no pager is invoked. Setting this environment variable
763 to an empty string or the value "cat" is equivalent to passing
764 --no-pager.
765 $SYSTEMD_LESS
767 Override the options passed to less (by default "FRSXMK").
768 Users might want to change two options in particular:
770 K
772 This option instructs the pager to exit immediately when Ctrl+C
773 is pressed. To allow less to handle Ctrl+C itself to switch
774 back to the pager command prompt, unset this option.
775 If the value of $SYSTEMD_LESS does not include "K", and the
777 pager that is invoked is less, Ctrl+C will be ignored by the
778 executable, and needs to be handled by the pager.
779 X
781 This option instructs the pager to not send termcap
782 initialization and deinitialization strings to the terminal. It
783 is set by default to allow command output to remain visible in
784 the terminal even after the pager exits. Nevertheless, this
785 prevents some pager functionality from working, in particular
786 paged output cannot be scrolled with the mouse.
787 See less(1) for more discussion.
789 $SYSTEMD_LESSCHARSET
791 Override the charset passed to less (by default "utf-8", if the
792 invoking terminal is determined to be UTF-8 compatible).
793 $SYSTEMD_PAGERSECURE
795 Takes a boolean argument. When true, the "secure" mode of the pager
796 is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE is not set
797 at all, secure mode is enabled if the effective UID is not the same
798 as the owner of the login session, see geteuid(2) and
799 sd_pid_get_owner_uid(3). In secure mode, LESSSECURE=1 will be set
800 when invoking the pager, and the pager shall disable commands that
801 open or create new files or start new subprocesses. When
802 $SYSTEMD_PAGERSECURE is not set at all, pagers which are not known
803 to implement secure mode will not be used. (Currently only less(1)
804 implements secure mode.)
805 Note: when commands are invoked with elevated privileges, for
807 example under sudo(8) or pkexec(1), care must be taken to ensure
808 that unintended interactive features are not enabled. "Secure" mode
809 for the pager may be enabled automatically as describe above.
810 Setting SYSTEMD_PAGERSECURE=0 or not removing it from the inherited
811 environment allows the user to invoke arbitrary commands. Note that
812 if the $SYSTEMD_PAGER or $PAGER variables are to be honoured,
813 $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
814 completely disable the pager using --no-pager instead.
815 $SYSTEMD_COLORS
817 Takes a boolean argument. When true, systemd and related utilities
818 will use colors in their output, otherwise the output will be
819 monochrome. Additionally, the variable can take one of the
820 following special values: "16", "256" to restrict the use of colors
821 to the base 16 or 256 ANSI colors, respectively. This can be
822 specified to override the automatic decision based on $TERM and
823 what the console is connected to.
824 $SYSTEMD_URLIFY
826 The value must be a boolean. Controls whether clickable links
827 should be generated in the output for terminal emulators supporting
828 this. This can be specified to override the decision that systemd
829 makes based on $TERM and other conditions.
830
832 Example 1. Create a user "waldo" in the administrator group "wheel",
833 and assign 500 MiB disk space to them.
834 homectl create waldo --real-name="Waldo McWaldo" -G wheel --disk-size=500M
836 Example 2. Create a user "wally" on a USB stick, and assign a maximum
838 of 500 concurrent tasks to them.
839 homectl create wally --real-name="Wally McWally" --image-path=/dev/disk/by-id/usb-SanDisk_Ultra_Fit_476fff954b2b5c44-0:0 --tasks-max=500
841 Example 3. Change nice level of user "odlaw" to +5 and make sure the
843 environment variable $SOME is set to the string "THING" for them on
844 login.
845 homectl update odlaw --nice=5 --setenv=SOME=THING
847 Example 4. Set up authentication with a YubiKey security token using
849 PKCS#11/PIV:
850 # Clear the Yubikey from any old keys (careful!)
852 ykman piv reset
853 # Generate a new private/public key pair on the device, store the public key in 'pubkey.pem'.
855 ykman piv generate-key -a RSA2048 9d pubkey.pem
856 # Create a self-signed certificate from this public key, and store it on the device.
858 ykman piv generate-certificate --subject "Knobelei" 9d pubkey.pem
859 # We don't need the public key on disk anymore
861 rm pubkey.pem
862 # Allow the security token to unlock the account of user 'lafcadio'.
864 homectl update lafcadio --pkcs11-token-uri=auto
865 Example 5. Set up authentication with a FIDO2 security token:
867 # Allow a FIDO2 security token to unlock the account of user 'nihilbaxter'.
869 homectl update nihilbaxter --fido2-device=auto
870
872 systemd(1), systemd-homed.service(8), homed.conf(5), userdbctl(1),
873 useradd(8), cryptsetup(8)
874
876 1. JSON User Records
877 https://systemd.io/USER_RECORD
878 2. Icon Naming Specification
880 https://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html
881 3. User/Group Name Syntax
883 https://systemd.io/USER_NAMES
884systemd 248 HOMECTL(1)