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">
4
5
<!ENTITY COMMANDNAME "mandos">
5
<!ENTITY TIMESTAMP "2022-04-24">
6
<!ENTITY % common SYSTEM "common.ent">
6
<!ENTITY TIMESTAMP "2008-08-29">
10
9
<refentry xmlns:xi="http://www.w3.org/2001/XInclude">
12
11
<title>Mandos Manual</title>
13
12
<!-- NWalsh’s docbook scripts use this to generate the footer: -->
14
13
<productname>Mandos</productname>
15
<productnumber>&version;</productnumber>
14
<productnumber>&VERSION;</productnumber>
16
15
<date>&TIMESTAMP;</date>
19
18
<firstname>Björn</firstname>
20
19
<surname>Påhlsson</surname>
22
<email>belorn@recompile.se</email>
21
<email>belorn@fukt.bsnet.se</email>
26
25
<firstname>Teddy</firstname>
27
26
<surname>Hogeborn</surname>
29
<email>teddy@recompile.se</email>
28
<email>teddy@fukt.bsnet.se</email>
46
34
<holder>Teddy Hogeborn</holder>
47
35
<holder>Björn Påhlsson</holder>
49
<xi:include href="legalnotice.xml"/>
39
This manual page is free software: you can redistribute it
40
and/or modify it under the terms of the GNU General Public
41
License as published by the Free Software Foundation,
42
either version 3 of the License, or (at your option) any
47
This manual page is distributed in the hope that it will
48
be useful, but WITHOUT ANY WARRANTY; without even the
49
implied warranty of MERCHANTABILITY or FITNESS FOR A
50
PARTICULAR PURPOSE. See the GNU General Public License
55
You should have received a copy of the GNU General Public
56
License along with this program; If not, see
57
<ulink url="http://www.gnu.org/licenses/"/>.
53
63
<refentrytitle>&COMMANDNAME;</refentrytitle>
54
64
<manvolnum>8</manvolnum>
58
68
<refname><command>&COMMANDNAME;</command></refname>
60
Gives encrypted passwords to authenticated Mandos clients
70
Sends encrypted passwords to authenticated Mandos clients
66
76
<command>&COMMANDNAME;</command>
68
<arg choice="plain"><option>--interface
69
<replaceable>NAME</replaceable></option></arg>
70
<arg choice="plain"><option>-i
71
<replaceable>NAME</replaceable></option></arg>
75
<arg choice="plain"><option>--address
76
<replaceable>ADDRESS</replaceable></option></arg>
77
<arg choice="plain"><option>-a
78
<replaceable>ADDRESS</replaceable></option></arg>
82
<arg choice="plain"><option>--port
83
<replaceable>PORT</replaceable></option></arg>
84
<arg choice="plain"><option>-p
85
<replaceable>PORT</replaceable></option></arg>
88
<arg><option>--priority
89
<replaceable>PRIORITY</replaceable></option></arg>
91
<arg><option>--servicename
92
<replaceable>NAME</replaceable></option></arg>
94
<arg><option>--configdir
95
<replaceable>DIRECTORY</replaceable></option></arg>
97
<arg><option>--debug</option></arg>
99
<arg><option>--debuglevel
100
<replaceable>LEVEL</replaceable></option></arg>
102
<arg><option>--no-dbus</option></arg>
104
<arg><option>--no-ipv6</option></arg>
106
<arg><option>--no-restore</option></arg>
108
<arg><option>--statedir
109
<replaceable>DIRECTORY</replaceable></option></arg>
111
<arg><option>--socket
112
<replaceable>FD</replaceable></option></arg>
114
<arg><option>--foreground</option></arg>
116
<arg><option>--no-zeroconf</option></arg>
77
<arg>--interface<arg choice="plain">NAME</arg></arg>
78
<arg>--address<arg choice="plain">ADDRESS</arg></arg>
79
<arg>--port<arg choice="plain">PORT</arg></arg>
80
<arg>--priority<arg choice="plain">PRIORITY</arg></arg>
81
<arg>--servicename<arg choice="plain">NAME</arg></arg>
82
<arg>--configdir<arg choice="plain">DIRECTORY</arg></arg>
86
<command>&COMMANDNAME;</command>
87
<arg>-i<arg choice="plain">NAME</arg></arg>
88
<arg>-a<arg choice="plain">ADDRESS</arg></arg>
89
<arg>-p<arg choice="plain">PORT</arg></arg>
90
<arg>--priority<arg choice="plain">PRIORITY</arg></arg>
91
<arg>--servicename<arg choice="plain">NAME</arg></arg>
92
<arg>--configdir<arg choice="plain">DIRECTORY</arg></arg>
119
96
<command>&COMMANDNAME;</command>
120
97
<group choice="req">
121
<arg choice="plain"><option>--help</option></arg>
122
<arg choice="plain"><option>-h</option></arg>
98
<arg choice="plain">-h</arg>
99
<arg choice="plain">--help</arg>
126
103
<command>&COMMANDNAME;</command>
127
<arg choice="plain"><option>--version</option></arg>
104
<arg choice="plain">--version</arg>
130
107
<command>&COMMANDNAME;</command>
131
<arg choice="plain"><option>--check</option></arg>
108
<arg choice="plain">--check</arg>
133
110
</refsynopsisdiv>
135
112
<refsect1 id="description">
136
113
<title>DESCRIPTION</title>
138
115
<command>&COMMANDNAME;</command> is a server daemon which
139
handles incoming requests for passwords for a pre-defined list
140
of client host computers. For an introduction, see
141
<citerefentry><refentrytitle>intro</refentrytitle>
142
<manvolnum>8mandos</manvolnum></citerefentry>. The Mandos server
143
uses Zeroconf to announce itself on the local network, and uses
144
TLS to communicate securely with and to authenticate the
145
clients. The Mandos server uses IPv6 to allow Mandos clients to
146
use IPv6 link-local addresses, since the clients will probably
147
not have any other addresses configured (see <xref
148
linkend="overview"/>). Any authenticated client is then given
149
the stored pre-encrypted password for that specific client.
116
handles incoming request for passwords for a pre-defined list of
117
client host computers. The Mandos server uses Zeroconf to
118
announce itself on the local network, and uses TLS to
119
communicate securely with and to authenticate the clients. The
120
Mandos server uses IPv6 to allow Mandos clients to use IPv6
121
link-local addresses, since the clients will probably not have
122
any other addresses configured (see <xref linkend="overview"/>).
123
Any authenticated client is then given the stored pre-encrypted
124
password for that specific client.
153
129
<refsect1 id="purpose">
154
130
<title>PURPOSE</title>
156
133
The purpose of this is to enable <emphasis>remote and unattended
157
134
rebooting</emphasis> of client host computer with an
158
135
<emphasis>encrypted root file system</emphasis>. See <xref
159
136
linkend="overview"/> for details.
163
141
<refsect1 id="options">
164
142
<title>OPTIONS</title>
167
<term><option>--help</option></term>
168
<term><option>-h</option></term>
146
<term><literal>-h</literal>, <literal>--help</literal></term>
171
149
Show a help message and exit
177
<term><option>--interface</option>
178
<replaceable>NAME</replaceable></term>
179
<term><option>-i</option>
180
<replaceable>NAME</replaceable></term>
155
<term><literal>-i</literal>, <literal>--interface <replaceable
156
>NAME</replaceable></literal></term>
182
158
<xi:include href="mandos-options.xml" xpointer="interface"/>
187
<term><option>--address
188
<replaceable>ADDRESS</replaceable></option></term>
190
<replaceable>ADDRESS</replaceable></option></term>
163
<term><literal>-a</literal>, <literal>--address <replaceable>
164
ADDRESS</replaceable></literal></term>
192
166
<xi:include href="mandos-options.xml" xpointer="address"/>
198
<replaceable>PORT</replaceable></option></term>
200
<replaceable>PORT</replaceable></option></term>
171
<term><literal>-p</literal>, <literal>--port <replaceable>
172
PORT</replaceable></literal></term>
202
174
<xi:include href="mandos-options.xml" xpointer="port"/>
207
<term><option>--check</option></term>
179
<term><literal>--check</literal></term>
210
182
Run the server’s self-tests. This includes any unit
217
<term><option>--debug</option></term>
189
<term><literal>--debug</literal></term>
219
191
<xi:include href="mandos-options.xml" xpointer="debug"/>
224
<term><option>--debuglevel
225
<replaceable>LEVEL</replaceable></option></term>
228
Set the debugging log level.
229
<replaceable>LEVEL</replaceable> is a string, one of
230
<quote><literal>CRITICAL</literal></quote>,
231
<quote><literal>ERROR</literal></quote>,
232
<quote><literal>WARNING</literal></quote>,
233
<quote><literal>INFO</literal></quote>, or
234
<quote><literal>DEBUG</literal></quote>, in order of
235
increasing verbosity. The default level is
236
<quote><literal>WARNING</literal></quote>.
242
<term><option>--priority <replaceable>
243
PRIORITY</replaceable></option></term>
196
<term><literal>--priority <replaceable>
197
PRIORITY</replaceable></literal></term>
245
199
<xi:include href="mandos-options.xml" xpointer="priority"/>
250
<term><option>--servicename
251
<replaceable>NAME</replaceable></option></term>
204
<term><literal>--servicename <replaceable>NAME</replaceable>
253
207
<xi:include href="mandos-options.xml"
254
208
xpointer="servicename"/>
259
<term><option>--configdir
260
<replaceable>DIRECTORY</replaceable></option></term>
213
<term><literal>--configdir <replaceable>DIR</replaceable>
263
217
Directory to search for configuration files. Default is
274
<term><option>--version</option></term>
228
<term><literal>--version</literal></term>
277
231
Prints the program version and exit.
283
<term><option>--no-dbus</option></term>
285
<xi:include href="mandos-options.xml" xpointer="dbus"/>
287
See also <xref linkend="dbus_interface"/>.
293
<term><option>--no-ipv6</option></term>
295
<xi:include href="mandos-options.xml" xpointer="ipv6"/>
300
<term><option>--no-restore</option></term>
302
<xi:include href="mandos-options.xml" xpointer="restore"/>
304
See also <xref linkend="persistent_state"/>.
310
<term><option>--statedir
311
<replaceable>DIRECTORY</replaceable></option></term>
313
<xi:include href="mandos-options.xml" xpointer="statedir"/>
318
<term><option>--socket
319
<replaceable>FD</replaceable></option></term>
321
<xi:include href="mandos-options.xml" xpointer="socket"/>
326
<term><option>--foreground</option></term>
328
<xi:include href="mandos-options.xml"
329
xpointer="foreground"/>
334
<term><option>--no-zeroconf</option></term>
336
<xi:include href="mandos-options.xml" xpointer="zeroconf"/>
343
238
<refsect1 id="overview">
344
239
<title>OVERVIEW</title>
345
240
<xi:include href="overview.xml"/>
347
242
This program is the server part. It is a normal server program
348
243
and will run in a normal system environment, not in an initial
349
<acronym>RAM</acronym> disk environment.
244
RAM disk environment.
353
248
<refsect1 id="protocol">
354
249
<title>NETWORK PROTOCOL</title>
408
303
</tbody></tgroup></table>
411
306
<refsect1 id="checking">
412
307
<title>CHECKING</title>
414
309
The server will, by default, continually check that the clients
415
310
are still up. If a client has not been confirmed as being up
416
311
for some time, the client is assumed to be compromised and is no
417
longer eligible to receive the encrypted password. (Manual
418
intervention is required to re-enable a client.) The timeout,
419
extended timeout, checker program, and interval between checks
420
can be configured both globally and per client; see
421
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
312
longer eligible to receive the encrypted password. The timeout,
313
checker program, and interval between checks can be configured
314
both globally and per client; see <citerefentry>
315
<refentrytitle>mandos-clients.conf</refentrytitle>
422
316
<manvolnum>5</manvolnum></citerefentry>.
426
<refsect1 id="approval">
427
<title>APPROVAL</title>
429
The server can be configured to require manual approval for a
430
client before it is sent its secret. The delay to wait for such
431
approval and the default action (approve or deny) can be
432
configured both globally and per client; see <citerefentry>
433
<refentrytitle>mandos-clients.conf</refentrytitle>
434
<manvolnum>5</manvolnum></citerefentry>. By default all clients
435
will be approved immediately without delay.
438
This can be used to deny a client its secret if not manually
439
approved within a specified time. It can also be used to make
440
the server delay before giving a client its secret, allowing
441
optional manual denying of this specific client.
446
320
<refsect1 id="logging">
447
321
<title>LOGGING</title>
449
323
The server will send log message with various severity levels to
450
<filename class="devicefile">/dev/log</filename>. With the
324
<filename>/dev/log</filename>. With the
451
325
<option>--debug</option> option, it will log even more messages,
452
326
and also show them on the console.
456
<refsect1 id="persistent_state">
457
<title>PERSISTENT STATE</title>
459
Client settings, initially read from
460
<filename>clients.conf</filename>, are persistent across
461
restarts, and run-time changes will override settings in
462
<filename>clients.conf</filename>. However, if a setting is
463
<emphasis>changed</emphasis> (or a client added, or removed) in
464
<filename>clients.conf</filename>, this will take precedence.
468
<refsect1 id="dbus_interface">
469
<title>D-BUS INTERFACE</title>
471
The server will by default provide a D-Bus system bus interface.
472
This interface will only be accessible by the root user or a
473
Mandos-specific user, if such a user exists. For documentation
474
of the D-Bus API, see the file <filename>DBUS-API</filename>.
478
330
<refsect1 id="exit_status">
479
331
<title>EXIT STATUS</title>
628
481
</informalexample>
631
484
<refsect1 id="security">
632
485
<title>SECURITY</title>
633
<refsect2 id="server">
486
<refsect2 id="SERVER">
634
487
<title>SERVER</title>
636
489
Running this <command>&COMMANDNAME;</command> server program
637
490
should not in itself present any security risk to the host
638
computer running it. The program switches to a non-root user
491
computer running it. The program does not need any special
492
privileges to run, and is designed to run as a non-root user.
642
<refsect2 id="clients">
495
<refsect2 id="CLIENTS">
643
496
<title>CLIENTS</title>
645
498
The server only gives out its stored data to clients which
646
does have the correct key ID of the stored key ID. This is
647
guaranteed by the fact that the client sends its public key in
648
the TLS handshake; this ensures it to be genuine. The server
649
computes the key ID of the key itself and looks up the key ID
650
in its list of clients. The <filename>clients.conf</filename>
499
does have the OpenPGP key of the stored fingerprint. This is
500
guaranteed by the fact that the client sends its OpenPGP
501
public key in the TLS handshake; this ensures it to be
502
genuine. The server computes the fingerprint of the key
503
itself and looks up the fingerprint in its list of
504
clients. The <filename>clients.conf</filename> file (see
652
505
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
653
506
<manvolnum>5</manvolnum></citerefentry>)
654
507
<emphasis>must</emphasis> be made non-readable by anyone
655
except the user starting the server (usually root).
508
except the user running the server.
658
511
As detailed in <xref linkend="checking"/>, the status of all
660
513
compromised if they are gone for too long.
516
If a client is compromised, its downtime should be duly noted
517
by the server which would therefore declare the client
518
invalid. But if the server was ever restarted, it would
519
re-read its client list from its configuration file and again
520
regard all clients therein as valid, and hence eligible to
521
receive their passwords. Therefore, be careful when
522
restarting servers if it is suspected that a client has, in
523
fact, been compromised by parties who may now be running a
524
fake Mandos client with the keys from the non-encrypted
525
initial RAM image of the client host. What should be done in
526
that case (if restarting the server program really is
527
necessary) is to stop the server program, edit the
528
configuration file to omit any suspect clients, and restart
663
532
For more details on client-side security, see
664
<citerefentry><refentrytitle>mandos-client</refentrytitle>
533
<citerefentry><refentrytitle>password-request</refentrytitle>
665
534
<manvolnum>8mandos</manvolnum></citerefentry>.
670
539
<refsect1 id="see_also">
671
540
<title>SEE ALSO</title>
673
<citerefentry><refentrytitle>intro</refentrytitle>
674
<manvolnum>8mandos</manvolnum></citerefentry>,
675
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
676
<manvolnum>5</manvolnum></citerefentry>,
677
<citerefentry><refentrytitle>mandos.conf</refentrytitle>
678
<manvolnum>5</manvolnum></citerefentry>,
679
<citerefentry><refentrytitle>mandos-client</refentrytitle>
680
<manvolnum>8mandos</manvolnum></citerefentry>,
681
<citerefentry><refentrytitle>sh</refentrytitle>
682
<manvolnum>1</manvolnum></citerefentry>
543
<refentrytitle>mandos.conf</refentrytitle>
544
<manvolnum>5</manvolnum></citerefentry>, <citerefentry>
545
<refentrytitle>mandos-clients.conf</refentrytitle>
546
<manvolnum>5</manvolnum></citerefentry>, <citerefentry>
547
<refentrytitle>password-request</refentrytitle>
548
<manvolnum>8mandos</manvolnum></citerefentry>, <citerefentry>
549
<refentrytitle>sh</refentrytitle><manvolnum>1</manvolnum>