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 "mandos">
6
<!ENTITY TIMESTAMP "2008-08-29">
5
<!ENTITY TIMESTAMP "2019-02-09">
6
<!ENTITY % common SYSTEM "common.ent">
9
10
<refentry xmlns:xi="http://www.w3.org/2001/XInclude">
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>
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/"/>.
48
<xi:include href="legalnotice.xml"/>
63
52
<refentrytitle>&COMMANDNAME;</refentrytitle>
64
53
<manvolnum>8</manvolnum>
68
57
<refname><command>&COMMANDNAME;</command></refname>
70
Sends encrypted passwords to authenticated Mandos clients
59
Gives encrypted passwords to authenticated Mandos clients
76
65
<command>&COMMANDNAME;</command>
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>
67
<arg choice="plain"><option>--interface
68
<replaceable>NAME</replaceable></option></arg>
69
<arg choice="plain"><option>-i
70
<replaceable>NAME</replaceable></option></arg>
74
<arg choice="plain"><option>--address
75
<replaceable>ADDRESS</replaceable></option></arg>
76
<arg choice="plain"><option>-a
77
<replaceable>ADDRESS</replaceable></option></arg>
81
<arg choice="plain"><option>--port
82
<replaceable>PORT</replaceable></option></arg>
83
<arg choice="plain"><option>-p
84
<replaceable>PORT</replaceable></option></arg>
87
<arg><option>--priority
88
<replaceable>PRIORITY</replaceable></option></arg>
90
<arg><option>--servicename
91
<replaceable>NAME</replaceable></option></arg>
93
<arg><option>--configdir
94
<replaceable>DIRECTORY</replaceable></option></arg>
96
<arg><option>--debug</option></arg>
98
<arg><option>--debuglevel
99
<replaceable>LEVEL</replaceable></option></arg>
101
<arg><option>--no-dbus</option></arg>
103
<arg><option>--no-ipv6</option></arg>
105
<arg><option>--no-restore</option></arg>
107
<arg><option>--statedir
108
<replaceable>DIRECTORY</replaceable></option></arg>
110
<arg><option>--socket
111
<replaceable>FD</replaceable></option></arg>
113
<arg><option>--foreground</option></arg>
115
<arg><option>--no-zeroconf</option></arg>
96
118
<command>&COMMANDNAME;</command>
97
119
<group choice="req">
98
<arg choice="plain">-h</arg>
99
<arg choice="plain">--help</arg>
120
<arg choice="plain"><option>--help</option></arg>
121
<arg choice="plain"><option>-h</option></arg>
103
125
<command>&COMMANDNAME;</command>
104
<arg choice="plain">--version</arg>
126
<arg choice="plain"><option>--version</option></arg>
107
129
<command>&COMMANDNAME;</command>
108
<arg choice="plain">--check</arg>
130
<arg choice="plain"><option>--check</option></arg>
110
132
</refsynopsisdiv>
112
134
<refsect1 id="description">
113
135
<title>DESCRIPTION</title>
115
137
<command>&COMMANDNAME;</command> is a server daemon which
116
138
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.
139
client host computers. For an introduction, see
140
<citerefentry><refentrytitle>intro</refentrytitle>
141
<manvolnum>8mandos</manvolnum></citerefentry>. The Mandos server
142
uses Zeroconf to announce itself on the local network, and uses
143
TLS to communicate securely with and to authenticate the
144
clients. The Mandos server uses IPv6 to allow Mandos clients to
145
use IPv6 link-local addresses, since the clients will probably
146
not have any other addresses configured (see <xref
147
linkend="overview"/>). Any authenticated client is then given
148
the stored pre-encrypted password for that specific client.
129
152
<refsect1 id="purpose">
130
153
<title>PURPOSE</title>
133
155
The purpose of this is to enable <emphasis>remote and unattended
134
156
rebooting</emphasis> of client host computer with an
135
157
<emphasis>encrypted root file system</emphasis>. See <xref
136
158
linkend="overview"/> for details.
141
162
<refsect1 id="options">
142
163
<title>OPTIONS</title>
146
<term><literal>-h</literal>, <literal>--help</literal></term>
166
<term><option>--help</option></term>
167
<term><option>-h</option></term>
149
170
Show a help message and exit
155
<term><literal>-i</literal>, <literal>--interface <replaceable
156
>NAME</replaceable></literal></term>
176
<term><option>--interface</option>
177
<replaceable>NAME</replaceable></term>
178
<term><option>-i</option>
179
<replaceable>NAME</replaceable></term>
158
181
<xi:include href="mandos-options.xml" xpointer="interface"/>
163
<term><literal>-a</literal>, <literal>--address <replaceable>
164
ADDRESS</replaceable></literal></term>
186
<term><option>--address
187
<replaceable>ADDRESS</replaceable></option></term>
189
<replaceable>ADDRESS</replaceable></option></term>
166
191
<xi:include href="mandos-options.xml" xpointer="address"/>
171
<term><literal>-p</literal>, <literal>--port <replaceable>
172
PORT</replaceable></literal></term>
197
<replaceable>PORT</replaceable></option></term>
199
<replaceable>PORT</replaceable></option></term>
174
201
<xi:include href="mandos-options.xml" xpointer="port"/>
179
<term><literal>--check</literal></term>
206
<term><option>--check</option></term>
182
209
Run the server’s self-tests. This includes any unit
189
<term><literal>--debug</literal></term>
216
<term><option>--debug</option></term>
191
218
<xi:include href="mandos-options.xml" xpointer="debug"/>
196
<term><literal>--priority <replaceable>
197
PRIORITY</replaceable></literal></term>
223
<term><option>--debuglevel
224
<replaceable>LEVEL</replaceable></option></term>
227
Set the debugging log level.
228
<replaceable>LEVEL</replaceable> is a string, one of
229
<quote><literal>CRITICAL</literal></quote>,
230
<quote><literal>ERROR</literal></quote>,
231
<quote><literal>WARNING</literal></quote>,
232
<quote><literal>INFO</literal></quote>, or
233
<quote><literal>DEBUG</literal></quote>, in order of
234
increasing verbosity. The default level is
235
<quote><literal>WARNING</literal></quote>.
241
<term><option>--priority <replaceable>
242
PRIORITY</replaceable></option></term>
199
244
<xi:include href="mandos-options.xml" xpointer="priority"/>
204
<term><literal>--servicename <replaceable>NAME</replaceable>
249
<term><option>--servicename
250
<replaceable>NAME</replaceable></option></term>
207
252
<xi:include href="mandos-options.xml"
208
253
xpointer="servicename"/>
213
<term><literal>--configdir <replaceable>DIR</replaceable>
258
<term><option>--configdir
259
<replaceable>DIRECTORY</replaceable></option></term>
217
262
Directory to search for configuration files. Default is
228
<term><literal>--version</literal></term>
273
<term><option>--version</option></term>
231
276
Prints the program version and exit.
282
<term><option>--no-dbus</option></term>
284
<xi:include href="mandos-options.xml" xpointer="dbus"/>
286
See also <xref linkend="dbus_interface"/>.
292
<term><option>--no-ipv6</option></term>
294
<xi:include href="mandos-options.xml" xpointer="ipv6"/>
299
<term><option>--no-restore</option></term>
301
<xi:include href="mandos-options.xml" xpointer="restore"/>
303
See also <xref linkend="persistent_state"/>.
309
<term><option>--statedir
310
<replaceable>DIRECTORY</replaceable></option></term>
312
<xi:include href="mandos-options.xml" xpointer="statedir"/>
317
<term><option>--socket
318
<replaceable>FD</replaceable></option></term>
320
<xi:include href="mandos-options.xml" xpointer="socket"/>
325
<term><option>--foreground</option></term>
327
<xi:include href="mandos-options.xml"
328
xpointer="foreground"/>
333
<term><option>--no-zeroconf</option></term>
335
<xi:include href="mandos-options.xml" xpointer="zeroconf"/>
238
342
<refsect1 id="overview">
239
343
<title>OVERVIEW</title>
240
344
<xi:include href="overview.xml"/>
242
346
This program is the server part. It is a normal server program
243
347
and will run in a normal system environment, not in an initial
244
RAM disk environment.
348
<acronym>RAM</acronym> disk environment.
248
352
<refsect1 id="protocol">
249
353
<title>NETWORK PROTOCOL</title>
303
407
</tbody></tgroup></table>
306
410
<refsect1 id="checking">
307
411
<title>CHECKING</title>
309
413
The server will, by default, continually check that the clients
310
414
are still up. If a client has not been confirmed as being up
311
415
for some time, the client is assumed to be compromised and is no
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>
416
longer eligible to receive the encrypted password. (Manual
417
intervention is required to re-enable a client.) The timeout,
418
extended timeout, checker program, and interval between checks
419
can be configured both globally and per client; see
420
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
421
<manvolnum>5</manvolnum></citerefentry>.
425
<refsect1 id="approval">
426
<title>APPROVAL</title>
428
The server can be configured to require manual approval for a
429
client before it is sent its secret. The delay to wait for such
430
approval and the default action (approve or deny) can be
431
configured both globally and per client; see <citerefentry>
315
432
<refentrytitle>mandos-clients.conf</refentrytitle>
316
<manvolnum>5</manvolnum></citerefentry>.
433
<manvolnum>5</manvolnum></citerefentry>. By default all clients
434
will be approved immediately without delay.
437
This can be used to deny a client its secret if not manually
438
approved within a specified time. It can also be used to make
439
the server delay before giving a client its secret, allowing
440
optional manual denying of this specific client.
320
445
<refsect1 id="logging">
321
446
<title>LOGGING</title>
323
448
The server will send log message with various severity levels to
324
<filename>/dev/log</filename>. With the
449
<filename class="devicefile">/dev/log</filename>. With the
325
450
<option>--debug</option> option, it will log even more messages,
326
451
and also show them on the console.
455
<refsect1 id="persistent_state">
456
<title>PERSISTENT STATE</title>
458
Client settings, initially read from
459
<filename>clients.conf</filename>, are persistent across
460
restarts, and run-time changes will override settings in
461
<filename>clients.conf</filename>. However, if a setting is
462
<emphasis>changed</emphasis> (or a client added, or removed) in
463
<filename>clients.conf</filename>, this will take precedence.
467
<refsect1 id="dbus_interface">
468
<title>D-BUS INTERFACE</title>
470
The server will by default provide a D-Bus system bus interface.
471
This interface will only be accessible by the root user or a
472
Mandos-specific user, if such a user exists. For documentation
473
of the D-Bus API, see the file <filename>DBUS-API</filename>.
330
477
<refsect1 id="exit_status">
331
478
<title>EXIT STATUS</title>
481
627
</informalexample>
484
630
<refsect1 id="security">
485
631
<title>SECURITY</title>
486
<refsect2 id="SERVER">
632
<refsect2 id="server">
487
633
<title>SERVER</title>
489
635
Running this <command>&COMMANDNAME;</command> server program
490
636
should not in itself present any security risk to the host
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.
637
computer running it. The program switches to a non-root user
495
<refsect2 id="CLIENTS">
641
<refsect2 id="clients">
496
642
<title>CLIENTS</title>
498
644
The server only gives out its stored data to clients which
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
645
does have the correct key ID of the stored key ID. This is
646
guaranteed by the fact that the client sends its public key in
647
the TLS handshake; this ensures it to be genuine. The server
648
computes the key ID of the key itself and looks up the key ID
649
in its list of clients. The <filename>clients.conf</filename>
505
651
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
506
652
<manvolnum>5</manvolnum></citerefentry>)
507
653
<emphasis>must</emphasis> be made non-readable by anyone
508
except the user running the server.
654
except the user starting the server (usually root).
511
657
As detailed in <xref linkend="checking"/>, the status of all
513
659
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
532
662
For more details on client-side security, see
533
<citerefentry><refentrytitle>password-request</refentrytitle>
663
<citerefentry><refentrytitle>mandos-client</refentrytitle>
534
664
<manvolnum>8mandos</manvolnum></citerefentry>.
539
669
<refsect1 id="see_also">
540
670
<title>SEE ALSO</title>
543
<refentrytitle>mandos-clients.conf</refentrytitle>
544
<manvolnum>5</manvolnum></citerefentry>, <citerefentry>
545
<refentrytitle>mandos.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>
672
<citerefentry><refentrytitle>intro</refentrytitle>
673
<manvolnum>8mandos</manvolnum></citerefentry>,
674
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
675
<manvolnum>5</manvolnum></citerefentry>,
676
<citerefentry><refentrytitle>mandos.conf</refentrytitle>
677
<manvolnum>5</manvolnum></citerefentry>,
678
<citerefentry><refentrytitle>mandos-client</refentrytitle>
679
<manvolnum>8mandos</manvolnum></citerefentry>,
680
<citerefentry><refentrytitle>sh</refentrytitle>
681
<manvolnum>1</manvolnum></citerefentry>