man/systemd-ask-password.xml

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  23
  24 <refentry id="systemd-ask-password"
  25           xmlns:xi="http://www.w3.org/2001/XInclude">
  26
  27         <refentryinfo>
  28                 <title>systemd-ask-password</title>
  29                 <productname>systemd</productname>
  30
  31                 <authorgroup>
  32                         <author>
  33                                 <contrib>Developer</contrib>
  34                                 <firstname>Lennart</firstname>
  35                                 <surname>Poettering</surname>
  36                                 <email>lennart@poettering.net</email>
  37                         </author>
  38                 </authorgroup>
  39         </refentryinfo>
  40
  41         <refmeta>
  42                 <refentrytitle>systemd-ask-password</refentrytitle>
  43                 <manvolnum>1</manvolnum>
  44         </refmeta>
  45
  46         <refnamediv>
  47                 <refname>systemd-ask-password</refname>
  48                 <refpurpose>Query the user for a system password</refpurpose>
  49         </refnamediv>
  50
  51         <refsynopsisdiv>
  52                 <cmdsynopsis>
  53                         <command>systemd-ask-password <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt">MESSAGE</arg></command>
  54                 </cmdsynopsis>
  55         </refsynopsisdiv>
  56
  57         <refsect1>
  58                 <title>Description</title>
  59
  60                 <para><command>systemd-ask-password</command> may be
  61                 used to query a system password or passphrase from the
  62                 user, using a question message specified on the
  63                 command line. When run from a TTY it will query a
  64                 password on the TTY and print it to standard output. When run
  65                 with no TTY or with <option>--no-tty</option> it will
  66                 query the password system-wide and allow active users
  67                 to respond via several agents. The latter is
  68                 only available to privileged processes.</para>
  69
  70                 <para>The purpose of this tool is to query system-wide
  71                 passwords -- that is passwords not attached to a
  72                 specific user account. Examples include: unlocking
  73                 encrypted hard disks when they are plugged in or at
  74                 boot, entering an SSL certificate passphrase for web
  75                 and VPN servers.</para>
  76
  77                 <para>Existing agents are: a boot-time password agent
  78                 asking the user for passwords using Plymouth; a
  79                 boot-time password agent querying the user directly on
  80                 the console; an agent requesting password input via a
  81                 <citerefentry project='man-pages'><refentrytitle>wall</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  82                 message; an agent suitable for running in a GNOME
  83                 session; a command line agent which can be started
  84                 temporarily to process queued password requests; a TTY
  85                 agent that is temporarily spawned during
  86                 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  87                 invocations.</para>
  88
  89                 <para>Additional password agents may be implemented
  90                 according to the <ulink
  91                 url="http://www.freedesktop.org/wiki/Software/systemd/PasswordAgents">systemd
  92                 Password Agent Specification</ulink>.</para>
  93
  94                 <para>If a password is queried on a TTY, the user may
  95                 press TAB to hide the asterisks normally shown for
  96                 each character typed. Pressing Backspace as first key
  97                 achieves the same effect.</para>
  98
  99         </refsect1>
 100
 101         <refsect1>
 102                 <title>Options</title>
 103
 104                 <para>The following options are understood:</para>
 105
 106                 <variablelist>
 107                         <varlistentry>
 108                                 <term><option>--icon=</option></term>
 109
 110                                 <listitem><para>Specify an icon name
 111                                 alongside the password query, which may
 112                                 be used in all agents supporting
 113                                 graphical display. The icon name
 114                                 should follow the <ulink
 115                                 url="http://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html">XDG
 116                                 Icon Naming
 117                                 Specification</ulink>.</para></listitem>
 118                         </varlistentry>
 119
 120                         <varlistentry>
 121                                 <term><option>--timeout=</option></term>
 122
 123                                 <listitem><para>Specify the query
 124                                 timeout in seconds. Defaults to
 125                                 90s. A timeout of 0 waits indefinitely.
 126                                 </para></listitem>
 127                         </varlistentry>
 128
 129                         <varlistentry>
 130                                 <term><option>--no-tty</option></term>
 131
 132                                 <listitem><para>Never ask for password
 133                                 on current TTY even if one is
 134                                 available. Always use agent
 135                                 system.</para></listitem>
 136                         </varlistentry>
 137
 138                         <varlistentry>
 139                                 <term><option>--accept-cached</option></term>
 140
 141                                 <listitem><para>If passed, accept
 142                                 cached passwords, i.e. passwords
 143                                 previously typed in.</para></listitem>
 144                         </varlistentry>
 145
 146                         <varlistentry>
 147                                 <term><option>--multiple</option></term>
 148
 149                                 <listitem><para>When used in
 150                                 conjunction with
 151                                 <option>--accept-cached</option>
 152                                 accept multiple passwords. This will
 153                                 output one password per
 154                                 line.</para></listitem>
 155                         </varlistentry>
 156
 157                         <xi:include href="standard-options.xml" xpointer="help" />
 158                 </variablelist>
 159
 160         </refsect1>
 161
 162         <refsect1>
 163                 <title>Exit status</title>
 164
 165                 <para>On success, 0 is returned, a non-zero failure
 166                 code otherwise.</para>
 167         </refsect1>
 168
 169         <refsect1>
 170                 <title>See Also</title>
 171                 <para>
 172                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 173                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 174                         <citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 175                         <citerefentry project='man-pages'><refentrytitle>wall</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 176                 </para>
 177         </refsect1>
 178
 179 </refentry>