11
12
<title>Mandos Manual</title>
12
13
<!-- Nwalsh’s docbook scripts use this to generate the footer: -->
13
14
<productname>Mandos</productname>
14
<productnumber>&VERSION;</productnumber>
15
<productnumber>&version;</productnumber>
15
16
<date>&TIMESTAMP;</date>
18
19
<firstname>Björn</firstname>
19
20
<surname>Påhlsson</surname>
21
<email>belorn@fukt.bsnet.se</email>
22
<email>belorn@recompile.se</email>
25
26
<firstname>Teddy</firstname>
26
27
<surname>Hogeborn</surname>
28
<email>teddy@fukt.bsnet.se</email>
29
<email>teddy@recompile.se</email>
34
45
<holder>Teddy Hogeborn</holder>
35
46
<holder>Björn Påhlsson</holder>
37
48
<xi:include href="legalnotice.xml"/>
41
52
<refentrytitle>&COMMANDNAME;</refentrytitle>
42
53
<manvolnum>8mandos</manvolnum>
46
57
<refname><command>&COMMANDNAME;</command></refname>
48
Run Mandos plugins. Pass data from first succesful one.
59
Run Mandos plugins, pass data from first to succeed.
54
65
<command>&COMMANDNAME;</command>
55
66
<group rep="repeat">
56
67
<arg choice="plain"><option>--global-env=<replaceable
57
>VAR</replaceable><literal>=</literal><replaceable
68
>ENV</replaceable><literal>=</literal><replaceable
58
69
>value</replaceable></option></arg>
59
<arg choice="plain"><option>-e
60
<replaceable>VAR</replaceable><literal>=</literal><replaceable
70
<arg choice="plain"><option>-G
71
<replaceable>ENV</replaceable><literal>=</literal><replaceable
61
72
>value</replaceable> </option></arg>
130
154
<title>DESCRIPTION</title>
132
156
<command>&COMMANDNAME;</command> is a program which is meant to
133
be specified as <quote>keyscript</quote> in <citerefentry>
134
<refentrytitle>crypttab</refentrytitle>
135
<manvolnum>5</manvolnum></citerefentry> for the root disk. The
136
aim of this program is therefore to output a password, which
137
then <citerefentry><refentrytitle>cryptsetup</refentrytitle>
138
<manvolnum>8</manvolnum></citerefentry> will use to try and
139
unlock the root disk.
157
be specified as a <quote>keyscript</quote> for the root disk in
158
<citerefentry><refentrytitle>crypttab</refentrytitle>
159
<manvolnum>5</manvolnum></citerefentry>. The aim of this
160
program is therefore to output a password, which then
161
<citerefentry><refentrytitle>cryptsetup</refentrytitle>
162
<manvolnum>8</manvolnum></citerefentry> will use to unlock the
142
166
This program is not meant to be invoked directly, but can be in
177
203
<replaceable>PLUGIN</replaceable><literal>:</literal
178
204
><replaceable>ENV</replaceable><literal>=</literal
179
205
><replaceable>value</replaceable></option></term>
181
207
<replaceable>PLUGIN</replaceable><literal>:</literal
182
208
><replaceable>ENV</replaceable><literal>=</literal
183
209
><replaceable>value</replaceable></option></term>
212
This option will add an environment variable setting to
213
the <replaceable>PLUGIN</replaceable> plugin. This will
214
override any inherited environment variables or
215
environment variables specified using
216
<option>--global-env</option>.
224
255
<option>--bar</option> with the option argument
225
256
<quote>baz</quote> is either
226
257
<userinput>--options-for=foo:--bar=baz</userinput> or
227
<userinput>--options-for=foo:--bar,baz</userinput>, but
228
<emphasis>not</emphasis>
229
<userinput>--options-for="foo:--bar baz"</userinput>.
258
<userinput>--options-for=foo:--bar,baz</userinput>. Using
259
<userinput>--options-for="foo:--bar baz"</userinput>. will
260
<emphasis>not</emphasis> work.
235
<term><option> --disable
266
<term><option>--disable
236
267
<replaceable>PLUGIN</replaceable></option></term>
238
269
<replaceable>PLUGIN</replaceable></option></term>
334
<term><option>--plugin-helper-dir
335
<replaceable>DIRECTORY</replaceable></option></term>
338
Specify a different plugin helper directory. The default
339
is <filename>/lib/mandos/plugin-helpers</filename>, which
340
will exist in the initial <acronym>RAM</acronym> disk
341
environment. (This will simply be passed to all plugins
342
via the <envar>MANDOSPLUGINHELPERDIR</envar> environment
343
variable. See <xref linkend="writing_plugins"/>)
349
<term><option>--config-file
350
<replaceable>FILE</replaceable></option></term>
353
Specify a different file to read additional options from.
354
See <xref linkend="files"/>. Other command line options
355
will override options specified in the file.
288
361
<term><option>--debug</option></term>
359
432
code will make this plugin-runner output the password from that
360
433
plugin, stop any other plugins, and exit.
436
<refsect2 id="writing_plugins">
437
<title>WRITING PLUGINS</title>
439
A plugin is simply a program which prints a password to its
440
standard output and then exits with a successful (zero) exit
441
status. If the exit status is not zero, any output on
442
standard output will be ignored by the plugin runner. Any
443
output on its standard error channel will simply be passed to
444
the standard error of the plugin runner, usually the system
448
If the password is a single-line, manually entered passprase,
449
a final trailing newline character should
450
<emphasis>not</emphasis> be printed.
453
The plugin will run in the initial RAM disk environment, so
454
care must be taken not to depend on any files or running
455
services not available there. Any helper executables required
456
by the plugin (which are not in the <envar>PATH</envar>) can
457
be placed in the plugin helper directory, the name of which
458
will be made available to the plugin via the
459
<envar>MANDOSPLUGINHELPERDIR</envar> environment variable.
462
The plugin must exit cleanly and free all allocated resources
463
upon getting the TERM signal, since this is what the plugin
464
runner uses to stop all other plugins when one plugin has
465
output a password and exited cleanly.
468
The plugin must not use resources, like for instance reading
469
from the standard input, without knowing that no other plugin
473
It is useful, but not required, for the plugin to take the
474
<option>--debug</option> option.
364
479
<refsect1 id="fallback">
407
528
everything from a <quote>#</quote> character to the end
408
529
of a line is ignored.
532
This program is meant to run in the initial RAM disk
533
environment, so that is where this file is assumed to
534
exist. The file does not need to exist in the normal
538
This file will be processed <emphasis>before</emphasis>
539
the normal command line options, so the latter can
540
override the former, if need be.
543
This file name is the default; the file to read for
544
arguments can be changed using the
545
<option>--config-file</option> option.
550
<term><filename class="directory"
551
>/lib/mandos/plugins.d</filename></term>
554
The default plugin directory; can be changed by the
555
<option>--plugin-dir</option> option.
560
<term><filename class="directory"
561
>/lib/mandos/plugin-helpers</filename></term>
564
The default plugin helper directory; can be changed by
565
the <option>--plugin-helper-dir</option> option.
416
573
<refsect1 id="bugs">
417
574
<title>BUGS</title>
576
The <option>--config-file</option> option is ignored when
577
specified from within a configuration file.
579
<xi:include href="bugs.xml"/>
422
582
<refsect1 id="examples">
423
583
<title>EXAMPLE</title>
586
Normal invocation needs no options:
589
<userinput>&COMMANDNAME;</userinput>
594
Run the program, but not the plugins, in debug mode:
598
<!-- do not wrap this line -->
599
<userinput>&COMMANDNAME; --debug</userinput>
605
Run all plugins, but run the <quote>foo</quote> plugin in
610
<!-- do not wrap this line -->
611
<userinput>&COMMANDNAME; --options-for=foo:--debug</userinput>
617
Run all plugins, but not the program, in debug mode:
621
<!-- do not wrap this line -->
622
<userinput>&COMMANDNAME; --global-options=--debug</userinput>
628
Read a different configuration file, run plugins from a
629
different directory, specify an alternate plugin helper
630
directory and add two options to the
631
<citerefentry><refentrytitle >mandos-client</refentrytitle>
632
<manvolnum>8mandos</manvolnum></citerefentry> plugin:
636
<!-- do not wrap this line -->
637
<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>
428
642
<refsect1 id="security">
429
643
<title>SECURITY</title>
645
This program will, when starting, try to switch to another user.
646
If it is started as root, it will succeed, and will by default
647
switch to user and group 65534, which are assumed to be
648
non-privileged. This user and group is then what all plugins
649
will be started as. Therefore, the only way to run a plugin as
650
a privileged user is to have the set-user-ID or set-group-ID bit
651
set on the plugin executable file (see <citerefentry>
652
<refentrytitle>execve</refentrytitle><manvolnum>2</manvolnum>
656
If this program is used as a keyscript in <citerefentry
657
><refentrytitle>crypttab</refentrytitle><manvolnum>5</manvolnum>
658
</citerefentry>, there is a slight risk that if this program
659
fails to work, there might be no way to boot the system except
660
for booting from another media and editing the initial RAM disk
661
image to not run this program. This is, however, unlikely,
662
since the <citerefentry><refentrytitle
663
>password-prompt</refentrytitle><manvolnum>8mandos</manvolnum>
664
</citerefentry> plugin will read a password from the console in
665
case of failure of the other plugins, and this plugin runner
666
will also, in case of catastrophic failure, itself fall back to
667
asking and outputting a password on the console (see <xref
668
linkend="fallback"/>).
434
672
<refsect1 id="see_also">
435
673
<title>SEE ALSO</title>
675
<citerefentry><refentrytitle>intro</refentrytitle>
676
<manvolnum>8mandos</manvolnum></citerefentry>,
437
677
<citerefentry><refentrytitle>cryptsetup</refentrytitle>
438
678
<manvolnum>8</manvolnum></citerefentry>,
679
<citerefentry><refentrytitle>crypttab</refentrytitle>
680
<manvolnum>5</manvolnum></citerefentry>,
681
<citerefentry><refentrytitle>execve</refentrytitle>
682
<manvolnum>2</manvolnum></citerefentry>,
439
683
<citerefentry><refentrytitle>mandos</refentrytitle>
440
684
<manvolnum>8</manvolnum></citerefentry>,
441
685
<citerefentry><refentrytitle>password-prompt</refentrytitle>
442
686
<manvolnum>8mandos</manvolnum></citerefentry>,
443
<citerefentry><refentrytitle>password-request</refentrytitle>
687
<citerefentry><refentrytitle>mandos-client</refentrytitle>
444
688
<manvolnum>8mandos</manvolnum></citerefentry>