1
1
<?xml version="1.0" encoding="UTF-8"?>
2
2
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3
3
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
4
<!ENTITY VERSION "1.0">
5
4
<!ENTITY COMMANDNAME "plugin-runner">
6
<!ENTITY TIMESTAMP "2008-09-01">
5
<!ENTITY TIMESTAMP "2008-09-30">
6
<!ENTITY % common SYSTEM "common.ent">
9
10
<refentry xmlns:xi="http://www.w3.org/2001/XInclude">
46
47
<refname><command>&COMMANDNAME;</command></refname>
48
Run Mandos plugins. Pass data from first succesful one.
49
Run Mandos plugins, pass data from first to succeed.
54
55
<command>&COMMANDNAME;</command>
55
56
<group rep="repeat">
56
57
<arg choice="plain"><option>--global-env=<replaceable
57
>VAR</replaceable><literal>=</literal><replaceable
58
>ENV</replaceable><literal>=</literal><replaceable
58
59
>value</replaceable></option></arg>
59
<arg choice="plain"><option>-e
60
<replaceable>VAR</replaceable><literal>=</literal><replaceable
60
<arg choice="plain"><option>-G
61
<replaceable>ENV</replaceable><literal>=</literal><replaceable
61
62
>value</replaceable> </option></arg>
66
67
>PLUGIN</replaceable><literal>:</literal><replaceable
67
68
>ENV</replaceable><literal>=</literal><replaceable
68
69
>value</replaceable></option></arg>
69
<arg choice="plain"><option>-f<replaceable>
70
<arg choice="plain"><option>-E<replaceable>
70
71
PLUGIN</replaceable><literal>:</literal><replaceable
71
72
>ENV</replaceable><literal>=</literal><replaceable
72
73
>value</replaceable> </option></arg>
83
84
<arg choice="plain"><option>--options-for=<replaceable
84
85
>PLUGIN</replaceable><literal>:</literal><replaceable
85
86
>OPTIONS</replaceable></option></arg>
86
<arg choice="plain"><option>-f<replaceable>
87
<arg choice="plain"><option>-o<replaceable>
87
88
PLUGIN</replaceable><literal>:</literal><replaceable
88
89
>OPTIONS</replaceable> </option></arg>
130
141
<title>DESCRIPTION</title>
132
143
<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.
144
be specified as a <quote>keyscript</quote> for the root disk in
145
<citerefentry><refentrytitle>crypttab</refentrytitle>
146
<manvolnum>5</manvolnum></citerefentry>. The aim of this
147
program is therefore to output a password, which then
148
<citerefentry><refentrytitle>cryptsetup</refentrytitle>
149
<manvolnum>8</manvolnum></citerefentry> will use to unlock the
142
153
This program is not meant to be invoked directly, but can be in
162
173
<term><option>--global-env
163
<replaceable>VAR</replaceable><literal>=</literal><replaceable
174
<replaceable>ENV</replaceable><literal>=</literal><replaceable
164
175
>value</replaceable></option></term>
166
<replaceable>VAR</replaceable><literal>=</literal><replaceable
177
<replaceable>ENV</replaceable><literal>=</literal><replaceable
167
178
>value</replaceable></option></term>
231
242
<option>--bar</option> with the option argument
232
243
<quote>baz</quote> is either
233
244
<userinput>--options-for=foo:--bar=baz</userinput> or
234
<userinput>--options-for=foo:--bar,baz</userinput>, but
235
<emphasis>not</emphasis>
236
<userinput>--options-for="foo:--bar baz"</userinput>.
245
<userinput>--options-for=foo:--bar,baz</userinput>. Using
246
<userinput>--options-for="foo:--bar baz"</userinput>. will
247
<emphasis>not</emphasis> work.
242
<term><option> --disable
253
<term><option>--disable
243
254
<replaceable>PLUGIN</replaceable></option></term>
245
256
<replaceable>PLUGIN</replaceable></option></term>
267
<term><option>--enable
268
<replaceable>PLUGIN</replaceable></option></term>
270
<replaceable>PLUGIN</replaceable></option></term>
273
Re-enable the plugin named
274
<replaceable>PLUGIN</replaceable>. This is only useful to
275
undo a previous <option>--disable</option> option, maybe
276
from the configuration file.
256
282
<term><option>--groupid
257
283
<replaceable>ID</replaceable></option></term>
366
404
code will make this plugin-runner output the password from that
367
405
plugin, stop any other plugins, and exit.
408
<refsect2 id="writing_plugins">
409
<title>WRITING PLUGINS</title>
411
A plugin is simply a program which prints a password to its
412
standard output and then exits with a successful (zero) exit
413
status. If the exit status is not zero, any output on
414
standard output will be ignored by the plugin runner. Any
415
output on its standard error channel will simply be passed to
416
the standard error of the plugin runner, usually the system
420
If the password is a single-line, manually entered passprase,
421
a final trailing newline character should
422
<emphasis>not</emphasis> be printed.
425
The plugin will run in the initial RAM disk environment, so
426
care must be taken not to depend on any files or running
427
services not available there.
430
The plugin must exit cleanly and free all allocated resources
431
upon getting the TERM signal, since this is what the plugin
432
runner uses to stop all other plugins when one plugin has
433
output a password and exited cleanly.
436
The plugin must not use resources, like for instance reading
437
from the standard input, without knowing that no other plugin
441
It is useful, but not required, for the plugin to take the
442
<option>--debug</option> option.
371
447
<refsect1 id="fallback">
415
495
of a line is ignored.
498
This program is meant to run in the initial RAM disk
499
environment, so that is where this file is assumed to
500
exist. The file does not need to exist in the normal
418
504
This file will be processed <emphasis>before</emphasis>
419
505
the normal command line options, so the latter can
420
506
override the former, if need be.
509
This file name is the default; the file to read for
510
arguments can be changed using the
511
<option>--config-file</option> option.
428
519
<refsect1 id="bugs">
429
520
<title>BUGS</title>
431
There is no <option>--enable</option> option to enable disabled
522
The <option>--config-file</option> option is ignored when
523
specified from within a configuration file.
436
527
<refsect1 id="examples">
437
528
<title>EXAMPLE</title>
531
Normal invocation needs no options:
534
<userinput>&COMMANDNAME;</userinput>
539
Run the program, but not the plugins, in debug mode:
543
<!-- do not wrap this line -->
544
<userinput>&COMMANDNAME; --debug</userinput>
550
Run all plugins, but run the <quote>foo</quote> plugin in
555
<!-- do not wrap this line -->
556
<userinput>&COMMANDNAME; --options-for=foo:--debug</userinput>
562
Run all plugins, but not the program, in debug mode:
566
<!-- do not wrap this line -->
567
<userinput>&COMMANDNAME; --global-options=--debug</userinput>
573
Run plugins from a different directory, read a different
574
configuration file, and add two options to the
575
<citerefentry><refentrytitle >mandos-client</refentrytitle>
576
<manvolnum>8mandos</manvolnum></citerefentry> plugin:
580
<!-- do not wrap this line -->
581
<userinput>&COMMANDNAME; --config-file=/etc/mandos/plugin-runner.conf --plugin-dir /usr/lib/mandos/plugins.d --options-for=mandos-client:--pubkey=/etc/keys/mandos/pubkey.txt,--seckey=/etc/keys/mandos/seckey.txt</userinput>
442
586
<refsect1 id="security">
443
587
<title>SECURITY</title>
589
This program will, when starting, try to switch to another user.
590
If it is started as root, it will succeed, and will by default
591
switch to user and group 65534, which are assumed to be
592
non-privileged. This user and group is then what all plugins
593
will be started as. Therefore, the only way to run a plugin as
594
a privileged user is to have the set-user-ID or set-group-ID bit
595
set on the plugin executable file (see <citerefentry>
596
<refentrytitle>execve</refentrytitle><manvolnum>2</manvolnum>
600
If this program is used as a keyscript in <citerefentry
601
><refentrytitle>crypttab</refentrytitle><manvolnum>5</manvolnum>
602
</citerefentry>, there is a slight risk that if this program
603
fails to work, there might be no way to boot the system except
604
for booting from another media and editing the initial RAM disk
605
image to not run this program. This is, however, unlikely,
606
since the <citerefentry><refentrytitle
607
>password-prompt</refentrytitle><manvolnum>8mandos</manvolnum>
608
</citerefentry> plugin will read a password from the console in
609
case of failure of the other plugins, and this plugin runner
610
will also, in case of catastrophic failure, itself fall back to
611
asking and outputting a password on the console (see <xref
612
linkend="fallback"/>).
451
619
<citerefentry><refentrytitle>cryptsetup</refentrytitle>
452
620
<manvolnum>8</manvolnum></citerefentry>,
621
<citerefentry><refentrytitle>crypttab</refentrytitle>
622
<manvolnum>5</manvolnum></citerefentry>,
623
<citerefentry><refentrytitle>execve</refentrytitle>
624
<manvolnum>2</manvolnum></citerefentry>,
453
625
<citerefentry><refentrytitle>mandos</refentrytitle>
454
626
<manvolnum>8</manvolnum></citerefentry>,
455
627
<citerefentry><refentrytitle>password-prompt</refentrytitle>
456
628
<manvolnum>8mandos</manvolnum></citerefentry>,
457
<citerefentry><refentrytitle>password-request</refentrytitle>
629
<citerefentry><refentrytitle>mandos-client</refentrytitle>
458
630
<manvolnum>8mandos</manvolnum></citerefentry>