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 "2019-07-24">
6
<!ENTITY % common SYSTEM "common.ent">
6
<!ENTITY OVERVIEW SYSTEM "overview.xml">
10
<refentry xmlns:xi="http://www.w3.org/2001/XInclude">
12
<title>Mandos Manual</title>
11
<title>&COMMANDNAME;</title>
13
12
<!-- NWalsh’s docbook scripts use this to generate the footer: -->
14
<productname>Mandos</productname>
15
<productnumber>&version;</productnumber>
16
<date>&TIMESTAMP;</date>
13
<productname>&COMMANDNAME;</productname>
14
<productnumber>&VERSION;</productnumber>
19
17
<firstname>Björn</firstname>
20
18
<surname>Påhlsson</surname>
22
<email>belorn@recompile.se</email>
20
<email>belorn@fukt.bsnet.se</email>
26
24
<firstname>Teddy</firstname>
27
25
<surname>Hogeborn</surname>
29
<email>teddy@recompile.se</email>
27
<email>teddy@fukt.bsnet.se</email>
46
33
<holder>Teddy Hogeborn</holder>
47
34
<holder>Björn Påhlsson</holder>
49
<xi:include href="legalnotice.xml"/>
38
This manual page is free software: you can redistribute it
39
and/or modify it under the terms of the GNU General Public
40
License as published by the Free Software Foundation,
41
either version 3 of the License, or (at your option) any
46
This manual page is distributed in the hope that it will
47
be useful, but WITHOUT ANY WARRANTY; without even the
48
implied warranty of MERCHANTABILITY or FITNESS FOR A
49
PARTICULAR PURPOSE. See the GNU General Public License
54
You should have received a copy of the GNU General Public
55
License along with this program; If not, see
56
<ulink url="http://www.gnu.org/licenses/"/>.
53
62
<refentrytitle>&COMMANDNAME;</refentrytitle>
54
63
<manvolnum>8</manvolnum>
58
67
<refname><command>&COMMANDNAME;</command></refname>
60
Gives encrypted passwords to authenticated Mandos clients
69
Sends encrypted passwords to authenticated Mandos clients
66
75
<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>
119
<command>&COMMANDNAME;</command>
121
<arg choice="plain"><option>--help</option></arg>
122
<arg choice="plain"><option>-h</option></arg>
126
<command>&COMMANDNAME;</command>
127
<arg choice="plain"><option>--version</option></arg>
130
<command>&COMMANDNAME;</command>
131
<arg choice="plain"><option>--check</option></arg>
76
<arg choice="opt">--interface<arg choice="plain">IF</arg></arg>
77
<arg choice="opt">--address<arg choice="plain">ADDRESS</arg></arg>
78
<arg choice="opt">--port<arg choice="plain">PORT</arg></arg>
79
<arg choice="opt">--priority<arg choice="plain">PRIORITY</arg></arg>
80
<arg choice="opt">--servicename<arg choice="plain">NAME</arg></arg>
81
<arg choice="opt">--configdir<arg choice="plain">DIRECTORY</arg></arg>
82
<arg choice="opt">--debug</arg>
85
<command>&COMMANDNAME;</command>
86
<arg choice="opt">-i<arg choice="plain">IF</arg></arg>
87
<arg choice="opt">-a<arg choice="plain">ADDRESS</arg></arg>
88
<arg choice="opt">-p<arg choice="plain">PORT</arg></arg>
89
<arg choice="opt">--priority<arg choice="plain">PRIORITY</arg></arg>
90
<arg choice="opt">--servicename<arg choice="plain">NAME</arg></arg>
91
<arg choice="opt">--configdir<arg choice="plain">DIRECTORY</arg></arg>
92
<arg choice="opt">--debug</arg>
95
<command>&COMMANDNAME;</command>
96
<arg choice="plain">--help</arg>
99
<command>&COMMANDNAME;</command>
100
<arg choice="plain">--version</arg>
103
<command>&COMMANDNAME;</command>
104
<arg choice="plain">--check</arg>
133
106
</refsynopsisdiv>
135
108
<refsect1 id="description">
136
109
<title>DESCRIPTION</title>
138
111
<command>&COMMANDNAME;</command> is a server daemon which
139
112
handles incoming request for passwords for a pre-defined list of
140
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.
113
client host computers. The Mandos server uses Zeroconf to
114
announce itself on the local network, and uses TLS to
115
communicate securely with and to authenticate the clients. The
116
Mandos server uses IPv6 to allow Mandos clients to use IPv6
117
link-local addresses, since the clients will probably not have
118
any other addresses configured (see <xref linkend="overview"/>).
119
Any authenticated client is then given the stored pre-encrypted
120
password for that specific client.
153
125
<refsect1 id="purpose">
154
126
<title>PURPOSE</title>
156
129
The purpose of this is to enable <emphasis>remote and unattended
157
130
rebooting</emphasis> of client host computer with an
158
131
<emphasis>encrypted root file system</emphasis>. See <xref
159
132
linkend="overview"/> for details.
163
137
<refsect1 id="options">
164
138
<title>OPTIONS</title>
167
<term><option>--help</option></term>
168
<term><option>-h</option></term>
142
<term><literal>-h</literal>, <literal>--help</literal></term>
171
145
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>
182
<xi:include href="mandos-options.xml" xpointer="interface"/>
187
<term><option>--address
188
<replaceable>ADDRESS</replaceable></option></term>
190
<replaceable>ADDRESS</replaceable></option></term>
192
<xi:include href="mandos-options.xml" xpointer="address"/>
198
<replaceable>PORT</replaceable></option></term>
200
<replaceable>PORT</replaceable></option></term>
202
<xi:include href="mandos-options.xml" xpointer="port"/>
207
<term><option>--check</option></term>
151
<term><literal>-i</literal>, <literal>--interface <replaceable>
152
IF</replaceable></literal></term>
155
Only announce the server and listen to requests on network
156
interface <replaceable>IF</replaceable>. Default is to
157
use all available interfaces.
163
<term><literal>-a</literal>, <literal>--address <replaceable>
164
ADDRESS</replaceable></literal></term>
167
If this option is used, the server will only listen to a
168
specific address. This must currently be an IPv6 address;
169
an IPv4 address can be specified using the
170
<quote><literal>::FFFF:192.0.2.3</literal></quote> syntax.
171
Also, if a link-local address is specified, an interface
172
should be set, since a link-local address is only valid on
173
a single interface. By default, the server will listen to
174
all available addresses.
180
<term><literal>-p</literal>, <literal>--port <replaceable>
181
PORT</replaceable></literal></term>
184
If this option is used, the server to bind to that
185
port. By default, the server will listen to an arbitrary
186
port given by the operating system.
192
<term><literal>--check</literal></term>
210
195
Run the server’s self-tests. This includes any unit
217
<term><option>--debug</option></term>
219
<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>
245
<xi:include href="mandos-options.xml" xpointer="priority"/>
250
<term><option>--servicename
251
<replaceable>NAME</replaceable></option></term>
253
<xi:include href="mandos-options.xml"
254
xpointer="servicename"/>
259
<term><option>--configdir
260
<replaceable>DIRECTORY</replaceable></option></term>
202
<term><literal>--debug</literal></term>
205
If the server is run in debug mode, it will run in the
206
foreground and print a lot of debugging information. The
207
default is <emphasis>not</emphasis> to run in debug mode.
213
<term><literal>--priority <replaceable>
214
PRIORITY</replaceable></literal></term>
217
GnuTLS priority string for the TLS handshake with the
218
clients. The default is
219
<quote><literal>SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP</literal></quote>.
220
See <citerefentry><refentrytitle>gnutls_priority_init
221
</refentrytitle><manvolnum>3</manvolnum></citerefentry>
222
for the syntax. <emphasis>Warning</emphasis>: changing
223
this may make the TLS handshake fail, making communication
224
with clients impossible.
230
<term><literal>--servicename <replaceable>NAME</replaceable>
234
Zeroconf service name. The default is
235
<quote><literal>Mandos</literal></quote>. You only need
236
to change this if you for some reason want to run more
237
than one server on the same <emphasis>host</emphasis>,
238
which would not normally be useful. If there are name
239
collisions on the same <emphasis>network</emphasis>, the
240
newer server will automatically rename itself to
241
<quote><literal>Mandos #2</literal></quote>, and so on;
242
therefore, this option is not needed in that case.
248
<term><literal>--configdir <replaceable>DIR</replaceable>
263
252
Directory to search for configuration files. Default is
274
<term><option>--version</option></term>
263
<term><literal>--version</literal></term>
277
266
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
273
<refsect1 id="overview">
344
274
<title>OVERVIEW</title>
345
<xi:include href="overview.xml"/>
347
277
This program is the server part. It is a normal server program
348
278
and will run in a normal system environment, not in an initial
349
<acronym>RAM</acronym> disk environment.
279
RAM disk environment.
353
283
<refsect1 id="protocol">
354
284
<title>NETWORK PROTOCOL</title>
408
338
</tbody></tgroup></table>
411
341
<refsect1 id="checking">
412
342
<title>CHECKING</title>
414
344
The server will, by default, continually check that the clients
415
345
are still up. If a client has not been confirmed as being up
416
346
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>
347
longer eligible to receive the encrypted password. The timeout,
348
checker program, and interval between checks can be configured
349
both globally and per client; see <citerefentry>
350
<refentrytitle>mandos.conf</refentrytitle>
351
<manvolnum>5</manvolnum></citerefentry> and <citerefentry>
352
<refentrytitle>mandos-clients.conf</refentrytitle>
422
353
<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
357
<refsect1 id="logging">
447
358
<title>LOGGING</title>
449
The server will send log message with various severity levels to
450
<filename class="devicefile">/dev/log</filename>. With the
360
The server will send log messaged with various severity levels
361
to <filename>/dev/log</filename>. With the
451
362
<option>--debug</option> option, it will log even more messages,
452
363
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
367
<refsect1 id="exit_status">
479
368
<title>EXIT STATUS</title>
568
<term><filename>/bin/sh</filename></term>
571
This is used to start the configured checker command for
572
each client. See <citerefentry>
573
<refentrytitle>mandos-clients.conf</refentrytitle>
574
<manvolnum>5</manvolnum></citerefentry> for details.
581
424
<refsect1 id="bugs">
582
425
<title>BUGS</title>
584
427
This server might, on especially fatal errors, emit a Python
585
428
backtrace. This could be considered a feature.
588
There is no fine-grained control over logging and debug output.
590
<xi:include href="bugs.xml"/>
593
<refsect1 id="example">
594
<title>EXAMPLE</title>
432
<refsect1 id="examples">
433
<title>EXAMPLES</title>
595
434
<informalexample>
597
436
Normal invocation needs no options:
600
<userinput>&COMMANDNAME;</userinput>
439
<userinput>mandos</userinput>
602
441
</informalexample>
603
442
<informalexample>
605
444
Run the server in debug mode, read configuration files from
606
the <filename class="directory">~/mandos</filename> directory,
607
and use the Zeroconf service name <quote>Test</quote> to not
608
collide with any other official Mandos server on this host:
445
the <filename>~/mandos</filename> directory, and use the
446
Zeroconf service name <quote>Test</quote> to not collide with
447
any other official Mandos server on this host:
612
451
<!-- do not wrap this line -->
613
<userinput>&COMMANDNAME; --debug --configdir ~/mandos --servicename Test</userinput>
452
<userinput>mandos --debug --configdir ~/mandos --servicename Test</userinput>
616
455
</informalexample>
624
463
<!-- do not wrap this line -->
625
<userinput>&COMMANDNAME; --interface eth7 --address fe80::aede:48ff:fe71:f6f2</userinput>
464
<userinput>mandos --interface eth7 --address fe80::aede:48ff:fe71:f6f2</userinput>
628
467
</informalexample>
631
470
<refsect1 id="security">
632
471
<title>SECURITY</title>
633
<refsect2 id="server">
634
473
<title>SERVER</title>
636
Running this <command>&COMMANDNAME;</command> server program
637
should not in itself present any security risk to the host
638
computer running it. The program switches to a non-root user
475
Running this &COMMANDNAME; server program should not in itself
476
present any security risk to the host computer running it.
477
The program does not need any special privileges to run, and
478
is designed to run as a non-root user.
642
<refsect2 id="clients">
643
482
<title>CLIENTS</title>
645
484
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>
485
does have the OpenPGP key of the stored fingerprint. This is
486
guaranteed by the fact that the client sends its OpenPGP
487
public key in the TLS handshake; this ensures it to be
488
genuine. The server computes the fingerprint of the key
489
itself and looks up the fingerprint in its list of
490
clients. The <filename>clients.conf</filename> file (see
652
491
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
653
492
<manvolnum>5</manvolnum></citerefentry>)
654
493
<emphasis>must</emphasis> be made non-readable by anyone
655
except the user starting the server (usually root).
494
except the user running the server.
658
497
As detailed in <xref linkend="checking"/>, the status of all
663
502
For more details on client-side security, see
664
<citerefentry><refentrytitle>mandos-client</refentrytitle>
503
<citerefentry><refentrytitle>password-request</refentrytitle>
665
504
<manvolnum>8mandos</manvolnum></citerefentry>.
670
509
<refsect1 id="see_also">
671
510
<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>
515
<refentrytitle>password-request</refentrytitle>
516
<manvolnum>8mandos</manvolnum>
521
This is the actual program which talks to this server.
522
Note that it is normally not invoked directly, and is only
523
run in the initial RAM disk environment, and not on a
524
fully started system.
687
530
<ulink url="http://www.zeroconf.org/">Zeroconf</ulink>
709
<ulink url="https://gnutls.org/">GnuTLS</ulink>
553
url="http://www.gnu.org/software/gnutls/">GnuTLS</ulink>
713
557
GnuTLS is the library this server uses to implement TLS for
714
558
communicating securely with the client, and at the same time
715
confidently get the client’s public key.
559
confidently get the client’s public OpenPGP key.
721
RFC 4291: <citetitle>IP Version 6 Addressing
722
Architecture</citetitle>
565
<citation>RFC 4291: <citetitle>IP Version 6 Addressing
566
Architecture</citetitle>, section 2.5.6, Link-Local IPv6
567
Unicast Addresses</citation>
727
<term>Section 2.2: <citetitle>Text Representation of
728
Addresses</citetitle></term>
729
<listitem><para/></listitem>
732
<term>Section 2.5.5.2: <citetitle>IPv4-Mapped IPv6
733
Address</citetitle></term>
734
<listitem><para/></listitem>
737
<term>Section 2.5.6, <citetitle>Link-Local IPv6 Unicast
738
Addresses</citetitle></term>
741
The clients use IPv6 link-local addresses, which are
742
immediately usable since a link-local addresses is
743
automatically assigned to a network interfaces when it
571
The clients use IPv6 link-local addresses, which are
572
immediately usable since a link-local addresses is
573
automatically assigned to a network interfaces when it is
753
RFC 5246: <citetitle>The Transport Layer Security (TLS)
754
Protocol Version 1.2</citetitle>
580
<citation>RFC 4346: <citetitle>The Transport Layer Security
581
(TLS) Protocol Version 1.1</citetitle></citation>
758
TLS 1.2 is the protocol implemented by GnuTLS.
585
TLS 1.1 is the protocol implemented by GnuTLS.
764
RFC 4880: <citetitle>OpenPGP Message Format</citetitle>
591
<citation>RFC 4880: <citetitle>OpenPGP Message
592
Format</citetitle></citation>