запросить у пользователя системный пароль (Query the user for a system password)
Имя (Name)
systemd-ask-password - Query the user for a system password
Синопсис (Synopsis)
systemd-ask-password [OPTIONS...] [MESSAGE]
Описание (Description)
systemd-ask-password may be used to query a system password or
passphrase from the user, using a question message specified on
the command line. When run from a TTY it will query a password on
the TTY and print it to standard output. When run with no TTY or
with --no-tty it will use the system-wide query mechanism, which
allows active users to respond via several agents, listed below.
The purpose of this tool is to query system-wide passwords — that
is passwords not attached to a specific user account. Examples
include: unlocking encrypted hard disks when they are plugged in
or at boot, entering an SSL certificate passphrase for web and
VPN servers.
Existing agents are:
• A boot-time password agent asking the user for passwords
using plymouth(8),
• A boot-time password agent querying the user directly on the
console — systemd-ask-password-console.service(8),
• An agent requesting password input via a wall(1) message —
systemd-ask-password-wall.service(8),
• A TTY agent that is temporarily spawned during systemctl(1)
invocations,
• A command line agent which can be started temporarily to
process queued password requests —
systemd-tty-ask-password-agent --query.
Answering system-wide password queries is a privileged operation,
hence all the agents listed above (except for the last one), run
as privileged system services. The last one also needs elevated
privileges, so should be run through sudo(8) or similar.
Additional password agents may be implemented according to the
systemd Password Agent Specification
If a password is queried on a TTY, the user may press TAB to hide
the asterisks normally shown for each character typed. Pressing
Backspace as first key achieves the same effect.
Параметры (Options)
The following options are understood:
--icon=
Specify an icon name alongside the password query, which may
be used in all agents supporting graphical display. The icon
name should follow the XDG Icon Naming Specification
--id=
Specify an identifier for this password query. This
identifier is freely choosable and allows recognition of
queries by involved agents. It should include the subsystem
doing the query and the specific object the query is done
for. Example: "--id=cryptsetup:/dev/sda5".
--keyname=
Configure a kernel keyring key name to use as cache for the
password. If set, then the tool will try to push any
collected passwords into the kernel keyring of the root user,
as a key of the specified name. If combined with
--accept-cached, it will also try to retrieve such cached
passwords from the key in the kernel keyring instead of
querying the user right away. By using this option, the
kernel keyring may be used as effective cache to avoid
repeatedly asking users for passwords, if there are multiple
objects that may be unlocked with the same password. The
cached key will have a timeout of 2.5min set, after which it
will be purged from the kernel keyring. Note that it is
possible to cache multiple passwords under the same keyname,
in which case they will be stored as NUL-separated list of
passwords. Use keyctl(1) to access the cached key via the
kernel keyring directly. Example: "--keyname=cryptsetup"
--credential=
Configure a credential to read the password from – if it
exists. This may be used in conjunction with the
LoadCredential= and SetCredential= settings in unit files.
See systemd.exec(5) for details. If not specified, defaults
to "password". This option has no effect if no credentials
directory is passed to the program (i.e.
$CREDENTIALS_DIRECTORY is not set) or if the no credential of
the specified name exists.
--timeout=
Specify the query timeout in seconds. Defaults to 90s. A
timeout of 0 waits indefinitely.
--echo=yes|no|masked
Controls whether to echo user input. Takes a boolean or the
special string "masked", the default being the latter. If
enabled the typed characters are echoed literally, which is
useful for prompting for usernames and other non-protected
data. If disabled the typed characters are not echoed in any
form, the user will not get feedback on their input. If set
to "masked", an asterisk ("*") is echoed for each character
typed. In this mode, if the user hits the tabulator key
("↹"), echo is turned off. (Alternatively, if the user hits
the backspace key ("⌫") while no data has been entered
otherwise, echo is turned off, too).
--echo, -e
Equivalent to --echo=yes, see above.
--emoji=yes|no|auto
Controls whether or not to prefix the query with a lock and
key emoji (рџ”ђ), if the TTY settings permit this. The default
is "auto", which defaults to "yes", unless --echo=yes is
given.
--no-tty
Never ask for password on current TTY even if one is
available. Always use agent system.
--accept-cached
If passed, accept cached passwords, i.e. passwords previously
entered.
--multiple
When used in conjunction with --accept-cached accept multiple
passwords. This will output one password per line.
--no-output
Do not print passwords to standard output. This is useful if
you want to store a password in kernel keyring with
--keyname= but do not want it to show up on screen or in
logs.
-n
By default, when writing the acquired password to standard
output it is suffixed by a newline character. This may be
turned off with the -n switch, similar to the switch of the
same name of the echo(1) command.
-h, --help
Print a short help text and exit.
Статус выхода (Exit)
On success, 0 is returned, a non-zero failure code otherwise.
Смотри также (See also)
systemd(1), systemd-ask-password-console.service(8),
systemd-tty-ask-password-agent(1), keyctl(1), plymouth(8),
wall(1)
Примечание (Note)
1. systemd Password Agent Specification
https://systemd.io/PASSWORD_AGENTS/
2. XDG Icon Naming Specification
http://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html
