systemd-ask-password (1)

systemd-ask-password [OPTIONS...] [MESSAGE]

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 query the password system-wide and allow active users to respond via several agents. The latter is only available to privileged processes.

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; a boot-time password agent querying the user directly on the console; an agent requesting password input via a wall(1) message; an agent suitable for running in a GNOME session; a command line agent which can be started temporarily to process queued password requests; a TTY agent that is temporarily spawned during systemctl(1) invocations.

Additional password agents may be implemented according to the \m[blue]systemd Password Agent Specification\m[]\s-2\u[1]\d\s+2.

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.

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 \m[blue]XDG Icon Naming Specification\m[]\s-2\u[2]\d\s+2.

--timeout=

Specify the query timeout in seconds. Defaults to 90s. A timeout of 0 waits indefinitely.

--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 typed in.

--multiple

When used in conjunction with --accept-cached accept multiple passwords. This will output one password per line.

-h, --help

Print a short help text and exit.

On success, 0 is returned, a non-zero failure code otherwise.

systemd(1), systemctl(1), plymouth(8), wall(1)

1.

systemd Password Agent Specification

http://www.freedesktop.org/wiki/Software/systemd/PasswordAgents

2.

XDG Icon Naming Specification

http://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html