127
120
<arg><option>--plugin-dir=<replaceable
128
121
>DIRECTORY</replaceable></option></arg>
123
<arg><option>--plugin-helper-dir=<replaceable
124
>DIRECTORY</replaceable></option></arg>
126
<arg><option>--config-file=<replaceable
127
>FILE</replaceable></option></arg>
130
129
<arg><option>--debug</option></arg>
133
132
<command>&COMMANDNAME;</command>
134
133
<group choice="req">
135
<arg choice='plain'><option>--help</option></arg>
136
<arg choice='plain'><option>-?</option></arg>
134
<arg choice="plain"><option>--help</option></arg>
135
<arg choice="plain"><option>-?</option></arg>
140
139
<command>&COMMANDNAME;</command>
141
<arg choice='plain'><option>--usage</option></arg>
140
<arg choice="plain"><option>--usage</option></arg>
144
143
<command>&COMMANDNAME;</command>
145
144
<group choice="req">
146
<arg choice='plain'><option>--version</option></arg>
147
<arg choice='plain'><option>-V</option></arg>
145
<arg choice="plain"><option>--version</option></arg>
146
<arg choice="plain"><option>-V</option></arg>
150
149
</refsynopsisdiv>
152
151
<refsect1 id="description">
153
152
<title>DESCRIPTION</title>
155
<command>&COMMANDNAME;</command> is a plugin runner that waits
156
for any of its plugins to return sucessfull with a password, and
157
passes it to cryptsetup as stdout message. This command is not
158
meant to be invoked directly, but is instead meant to be run by
159
cryptsetup by being specified in /etc/crypttab as a keyscript
160
and subsequlently started in the initrd environment. See
154
<command>&COMMANDNAME;</command> is a program which is meant to
155
be specified as a <quote>keyscript</quote> for the root disk in
161
156
<citerefentry><refentrytitle>crypttab</refentrytitle>
162
<manvolnum>5</manvolnum></citerefentry> for more information on
167
plugins is looked for in the plugins directory which by default will be
168
/conf/conf.d/mandos/plugins.d if not changed by option --plugin-dir.
157
<manvolnum>5</manvolnum></citerefentry>. The aim of this
158
program is therefore to output a password, which then
159
<citerefentry><refentrytitle>cryptsetup</refentrytitle>
160
<manvolnum>8</manvolnum></citerefentry> will use to unlock the
164
This program is not meant to be invoked directly, but can be in
165
order to test it. Note that any password obtained will simply
166
be output on standard output.
170
<refsect1 id="purpose">
171
<title>PURPOSE</title>
173
The purpose of this is to enable <emphasis>remote and unattended
174
rebooting</emphasis> of client host computer with an
175
<emphasis>encrypted root file system</emphasis>. See <xref
176
linkend="overview"/> for details.
172
181
<title>OPTIONS</title>
175
<term><literal>-g</literal>,<literal>--global-options
176
<replaceable>OPTIONS</replaceable></literal></term>
179
Global options given to all plugins as additional start
180
arguments. Options are specified with a -o flag followed
181
by a comma separated string of options.
187
<term><literal>-o</literal>,<literal> --options-for
188
<replaceable>PLUGIN</replaceable>:<replaceable>OPTION</replaceable>
192
Plugin specific options given to the plugin as additional
193
start arguments. Options are specified with a -o flag
194
followed by a comma separated string of options.
200
<term><literal>-d</literal>,<literal> --disable
201
<replaceable>PLUGIN</replaceable>
205
Disable a specific plugin
211
<term><literal>--groupid <replaceable>ID</replaceable>
215
Group ID the plugins will run as
221
<term><literal>--userid <replaceable>ID</replaceable>
225
User ID the plugins will run as
231
<term><literal>--plugin-dir <replaceable>DIRECTORY</replaceable>
235
Specify a different plugin directory
241
<term><literal>--debug</literal></term>
250
<term><literal>-?</literal>, <literal>--help</literal></term>
259
<term><literal>--usage</literal></term>
262
Gives a short usage message
268
<term><literal>-V</literal>, <literal>--version</literal></term>
271
Prints the program version
184
<term><option>--global-env
185
<replaceable>ENV</replaceable><literal>=</literal><replaceable
186
>value</replaceable></option></term>
188
<replaceable>ENV</replaceable><literal>=</literal><replaceable
189
>value</replaceable></option></term>
192
This option will add an environment variable setting to
193
all plugins. This will override any inherited environment
200
<term><option>--env-for
201
<replaceable>PLUGIN</replaceable><literal>:</literal
202
><replaceable>ENV</replaceable><literal>=</literal
203
><replaceable>value</replaceable></option></term>
205
<replaceable>PLUGIN</replaceable><literal>:</literal
206
><replaceable>ENV</replaceable><literal>=</literal
207
><replaceable>value</replaceable></option></term>
210
This option will add an environment variable setting to
211
the <replaceable>PLUGIN</replaceable> plugin. This will
212
override any inherited environment variables or
213
environment variables specified using
214
<option>--global-env</option>.
220
<term><option>--global-options
221
<replaceable>OPTIONS</replaceable></option></term>
223
<replaceable>OPTIONS</replaceable></option></term>
226
Pass some options to <emphasis>all</emphasis> plugins.
227
<replaceable>OPTIONS</replaceable> is a comma separated
228
list of options. This is not a very useful option, except
229
for specifying the <quote><option>--debug</option></quote>
230
option to all plugins.
236
<term><option>--options-for
237
<replaceable>PLUGIN</replaceable><literal>:</literal
238
><replaceable>OPTION</replaceable></option></term>
240
<replaceable>PLUGIN</replaceable><literal>:</literal
241
><replaceable>OPTION</replaceable></option></term>
244
Pass some options to a specific plugin. <replaceable
245
>PLUGIN</replaceable> is the name (file basename) of a
246
plugin, and <replaceable>OPTIONS</replaceable> is a comma
247
separated list of options.
250
Note that since options are not split on whitespace, the
251
way to pass, to the plugin
252
<quote><filename>foo</filename></quote>, the option
253
<option>--bar</option> with the option argument
254
<quote>baz</quote> is either
255
<userinput>--options-for=foo:--bar=baz</userinput> or
256
<userinput>--options-for=foo:--bar,baz</userinput>. Using
257
<userinput>--options-for="foo:--bar baz"</userinput>. will
258
<emphasis>not</emphasis> work.
264
<term><option>--disable
265
<replaceable>PLUGIN</replaceable></option></term>
267
<replaceable>PLUGIN</replaceable></option></term>
270
Disable the plugin named
271
<replaceable>PLUGIN</replaceable>. The plugin will not be
278
<term><option>--enable
279
<replaceable>PLUGIN</replaceable></option></term>
281
<replaceable>PLUGIN</replaceable></option></term>
284
Re-enable the plugin named
285
<replaceable>PLUGIN</replaceable>. This is only useful to
286
undo a previous <option>--disable</option> option, maybe
287
from the configuration file.
293
<term><option>--groupid
294
<replaceable>ID</replaceable></option></term>
297
Change to group ID <replaceable>ID</replaceable> on
298
startup. The default is 65534. All plugins will be
299
started using this group ID. <emphasis>Note:</emphasis>
300
This must be a number, not a name.
306
<term><option>--userid
307
<replaceable>ID</replaceable></option></term>
310
Change to user ID <replaceable>ID</replaceable> on
311
startup. The default is 65534. All plugins will be
312
started using this user ID. <emphasis>Note:</emphasis>
313
This must be a number, not a name.
319
<term><option>--plugin-dir
320
<replaceable>DIRECTORY</replaceable></option></term>
323
Specify a different plugin directory. The default is
324
<filename>/lib/mandos/plugins.d</filename>, which will
325
exist in the initial <acronym>RAM</acronym> disk
332
<term><option>--plugin-helper-dir
333
<replaceable>DIRECTORY</replaceable></option></term>
336
Specify a different plugin helper directory. The default
337
is <filename>/lib/mandos/plugin-helpers</filename>, which
338
will exist in the initial <acronym>RAM</acronym> disk
339
environment. (This will simply be passed to all plugins
340
via the <envar>MANDOSPLUGINHELPERDIR</envar> environment
341
variable. See <xref linkend="writing_plugins"/>)
347
<term><option>--config-file
348
<replaceable>FILE</replaceable></option></term>
351
Specify a different file to read additional options from.
352
See <xref linkend="files"/>. Other command line options
353
will override options specified in the file.
359
<term><option>--debug</option></term>
362
Enable debug mode. This will enable a lot of output to
363
standard error about what the program is doing. The
364
program will still perform all other functions normally.
365
The default is to <emphasis>not</emphasis> run in debug
369
The plugins will <emphasis>not</emphasis> be affected by
371
<userinput><option>--global-options=--debug</option></userinput>
372
if complete debugging eruption is desired.
378
<term><option>--help</option></term>
379
<term><option>-?</option></term>
382
Gives a help message about options and their meanings.
388
<term><option>--usage</option></term>
391
Gives a short usage message.
397
<term><option>--version</option></term>
398
<term><option>-V</option></term>
401
Prints the program version.
408
<refsect1 id="overview">
409
<title>OVERVIEW</title>
410
<xi:include href="overview.xml"/>
412
This program will run on the client side in the initial
413
<acronym>RAM</acronym> disk environment, and is responsible for
414
getting a password. It does this by running plugins, one of
415
which will normally be the actual client program communicating
419
<refsect1 id="plugins">
420
<title>PLUGINS</title>
422
This program will get a password by running a number of
423
<firstterm>plugins</firstterm>, which are simply executable
424
programs in a directory in the initial <acronym>RAM</acronym>
425
disk environment. The default directory is
426
<filename>/lib/mandos/plugins.d</filename>, but this can be
427
changed with the <option>--plugin-dir</option> option. The
428
plugins are started in parallel, and the first plugin to output
429
a password <emphasis>and</emphasis> exit with a successful exit
430
code will make this plugin-runner output the password from that
431
plugin, stop any other plugins, and exit.
434
<refsect2 id="writing_plugins">
435
<title>WRITING PLUGINS</title>
437
A plugin is simply a program which prints a password to its
438
standard output and then exits with a successful (zero) exit
439
status. If the exit status is not zero, any output on
440
standard output will be ignored by the plugin runner. Any
441
output on its standard error channel will simply be passed to
442
the standard error of the plugin runner, usually the system
446
If the password is a single-line, manually entered passprase,
447
a final trailing newline character should
448
<emphasis>not</emphasis> be printed.
451
The plugin will run in the initial RAM disk environment, so
452
care must be taken not to depend on any files or running
453
services not available there. Any helper executables required
454
by the plugin (which are not in the <envar>PATH</envar>) can
455
be placed in the plugin helper directory, the name of which
456
will be made available to the plugin via the
457
<envar>MANDOSPLUGINHELPERDIR</envar> environment variable.
460
The plugin must exit cleanly and free all allocated resources
461
upon getting the TERM signal, since this is what the plugin
462
runner uses to stop all other plugins when one plugin has
463
output a password and exited cleanly.
466
The plugin must not use resources, like for instance reading
467
from the standard input, without knowing that no other plugin
471
It is useful, but not required, for the plugin to take the
472
<option>--debug</option> option.
477
<refsect1 id="fallback">
478
<title>FALLBACK</title>
480
If no plugins succeed, this program will, as a fallback, ask for
481
a password on the console using <citerefentry><refentrytitle
482
>getpass</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
483
and output it. This is not meant to be the normal mode of
484
operation, as there is a separate plugin for getting a password
278
489
<refsect1 id="exit_status">
279
490
<title>EXIT STATUS</title>
492
Exit status of this program is zero if no errors were
493
encountered, and otherwise not. The fallback (see <xref
494
linkend="fallback"/>) may or may not have succeeded in either
499
<refsect1 id="environment">
500
<title>ENVIRONMENT</title>
502
This program does not use any environment variables itself, it
503
only passes on its environment to all the plugins. The
504
environment passed to plugins can be modified using the
505
<option>--global-env</option> and <option>--env-for</option>
506
options. Also, the <option>--plugin-helper-dir</option> option
507
will affect the environment variable
508
<envar>MANDOSPLUGINHELPERDIR</envar> for the plugins.
512
<refsect1 id="files">
285
513
<title>FILES</title>
290
<refsect1 id="notes">
518
>/conf/conf.d/mandos/plugin-runner.conf</filename></term>
521
Since this program will be run as a keyscript, there is
522
little to no opportunity to pass command line arguments
523
to it. Therefore, it will <emphasis>also</emphasis>
524
read this file and use its contents as
525
whitespace-separated command line options. Also,
526
everything from a <quote>#</quote> character to the end
527
of a line is ignored.
530
This program is meant to run in the initial RAM disk
531
environment, so that is where this file is assumed to
532
exist. The file does not need to exist in the normal
536
This file will be processed <emphasis>before</emphasis>
537
the normal command line options, so the latter can
538
override the former, if need be.
541
This file name is the default; the file to read for
542
arguments can be changed using the
543
<option>--config-file</option> option.
548
<term><filename class="directory"
549
>/lib/mandos/plugins.d</filename></term>
552
The default plugin directory; can be changed by the
553
<option>--plugin-dir</option> option.
558
<term><filename class="directory"
559
>/lib/mandos/plugin-helpers</filename></term>
562
The default plugin helper directory; can be changed by
563
the <option>--plugin-helper-dir</option> option.
296
571
<refsect1 id="bugs">
297
572
<title>BUGS</title>
574
The <option>--config-file</option> option is ignored when
575
specified from within a configuration file.
577
<xi:include href="bugs.xml"/>
302
580
<refsect1 id="examples">
303
581
<title>EXAMPLE</title>
584
Normal invocation needs no options:
587
<userinput>&COMMANDNAME;</userinput>
592
Run the program, but not the plugins, in debug mode:
596
<!-- do not wrap this line -->
597
<userinput>&COMMANDNAME; --debug</userinput>
603
Run all plugins, but run the <quote>foo</quote> plugin in
608
<!-- do not wrap this line -->
609
<userinput>&COMMANDNAME; --options-for=foo:--debug</userinput>
615
Run all plugins, but not the program, in debug mode:
619
<!-- do not wrap this line -->
620
<userinput>&COMMANDNAME; --global-options=--debug</userinput>
626
Read a different configuration file, run plugins from a
627
different directory, specify an alternate plugin helper
628
directory and add two options to the
629
<citerefentry><refentrytitle >mandos-client</refentrytitle>
630
<manvolnum>8mandos</manvolnum></citerefentry> plugin:
634
<!-- do not wrap this line -->
635
<userinput>cd /etc/keys/mandos; &COMMANDNAME; --config-file=/etc/mandos/plugin-runner.conf --plugin-dir /usr/lib/x86_64-linux-gnu/mandos/plugins.d --plugin-helper-dir /usr/lib/x86_64-linux-gnu/mandos/plugin-helpers --options-for=mandos-client:--pubkey=pubkey.txt,--seckey=seckey.txt</userinput>
308
640
<refsect1 id="security">
309
641
<title>SECURITY</title>
643
This program will, when starting, try to switch to another user.
644
If it is started as root, it will succeed, and will by default
645
switch to user and group 65534, which are assumed to be
646
non-privileged. This user and group is then what all plugins
647
will be started as. Therefore, the only way to run a plugin as
648
a privileged user is to have the set-user-ID or set-group-ID bit
649
set on the plugin executable file (see <citerefentry>
650
<refentrytitle>execve</refentrytitle><manvolnum>2</manvolnum>
654
If this program is used as a keyscript in <citerefentry
655
><refentrytitle>crypttab</refentrytitle><manvolnum>5</manvolnum>
656
</citerefentry>, there is a slight risk that if this program
657
fails to work, there might be no way to boot the system except
658
for booting from another media and editing the initial RAM disk
659
image to not run this program. This is, however, unlikely,
660
since the <citerefentry><refentrytitle
661
>password-prompt</refentrytitle><manvolnum>8mandos</manvolnum>
662
</citerefentry> plugin will read a password from the console in
663
case of failure of the other plugins, and this plugin runner
664
will also, in case of catastrophic failure, itself fall back to
665
asking and outputting a password on the console (see <xref
666
linkend="fallback"/>).
314
670
<refsect1 id="see_also">
315
671
<title>SEE ALSO</title>
673
<citerefentry><refentrytitle>intro</refentrytitle>
674
<manvolnum>8mandos</manvolnum></citerefentry>,
317
675
<citerefentry><refentrytitle>cryptsetup</refentrytitle>
318
676
<manvolnum>8</manvolnum></citerefentry>,
677
<citerefentry><refentrytitle>crypttab</refentrytitle>
678
<manvolnum>5</manvolnum></citerefentry>,
679
<citerefentry><refentrytitle>execve</refentrytitle>
680
<manvolnum>2</manvolnum></citerefentry>,
319
681
<citerefentry><refentrytitle>mandos</refentrytitle>
320
682
<manvolnum>8</manvolnum></citerefentry>,
321
683
<citerefentry><refentrytitle>password-prompt</refentrytitle>
322
684
<manvolnum>8mandos</manvolnum></citerefentry>,
323
<citerefentry><refentrytitle>password-request</refentrytitle>
685
<citerefentry><refentrytitle>mandos-client</refentrytitle>
324
686
<manvolnum>8mandos</manvolnum></citerefentry>
329
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330
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