1
<?xml version='1.0' encoding='UTF-8'?>
2
<?xml-stylesheet type="text/xsl"
3
href="http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl"?>
1
<?xml version="1.0" encoding="UTF-8"?>
4
2
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
5
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
6
<!ENTITY VERSION "1.0">
3
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
7
4
<!ENTITY COMMANDNAME "mandos">
5
<!ENTITY TIMESTAMP "2019-07-24">
6
<!ENTITY % common SYSTEM "common.ent">
12
<title>&COMMANDNAME;</title>
13
<!-- NWalsh's docbook scripts use this to generate the footer: -->
14
<productname>&COMMANDNAME;</productname>
15
<productnumber>&VERSION;</productnumber>
10
<refentry xmlns:xi="http://www.w3.org/2001/XInclude">
12
<title>Mandos Manual</title>
13
<!-- NWalsh’s docbook scripts use this to generate the footer: -->
14
<productname>Mandos</productname>
15
<productnumber>&version;</productnumber>
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
46
<holder>Teddy Hogeborn</holder>
35
47
<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/"/>.
49
<xi:include href="legalnotice.xml"/>
63
53
<refentrytitle>&COMMANDNAME;</refentrytitle>
64
54
<manvolnum>8</manvolnum>
68
58
<refname><command>&COMMANDNAME;</command></refname>
70
Sends encrypted passwords to authenticated Mandos clients
60
Gives encrypted passwords to authenticated Mandos clients
76
66
<command>&COMMANDNAME;</command>
77
<arg choice='opt'>--interface<arg choice='plain'>IF</arg></arg>
78
<arg choice='opt'>--address<arg choice='plain'>ADDRESS</arg></arg>
79
<arg choice='opt'>--port<arg choice='plain'>PORT</arg></arg>
80
<arg choice='opt'>--priority<arg choice='plain'>PRIORITY</arg></arg>
81
<arg choice='opt'>--servicename<arg choice='plain'>NAME</arg></arg>
82
<arg choice='opt'>--configdir<arg choice='plain'>DIRECTORY</arg></arg>
83
<arg choice='opt'>--debug</arg>
86
<command>&COMMANDNAME;</command>
87
<arg choice='opt'>-i<arg choice='plain'>IF</arg></arg>
88
<arg choice='opt'>-a<arg choice='plain'>ADDRESS</arg></arg>
89
<arg choice='opt'>-p<arg choice='plain'>PORT</arg></arg>
90
<arg choice='opt'>--priority<arg choice='plain'>PRIORITY</arg></arg>
91
<arg choice='opt'>--servicename<arg choice='plain'>NAME</arg></arg>
92
<arg choice='opt'>--configdir<arg choice='plain'>DIRECTORY</arg></arg>
93
<arg choice='opt'>--debug</arg>
96
<command>&COMMANDNAME;</command>
97
<arg choice='plain'>--help</arg>
100
<command>&COMMANDNAME;</command>
101
<arg choice='plain'>--version</arg>
104
<command>&COMMANDNAME;</command>
105
<arg choice='plain'>--check</arg>
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>
107
133
</refsynopsisdiv>
109
135
<refsect1 id="description">
110
136
<title>DESCRIPTION</title>
112
138
<command>&COMMANDNAME;</command> is a server daemon which
113
139
handles incoming request for passwords for a pre-defined list of
114
client host computers. The Mandos server uses Zeroconf to
115
announce itself on the local network, and uses GnuTLS to
116
communicate securely with and to authenticate the clients.
117
Mandos uses IPv6 link-local addresses, since the clients are
118
assumed to not have any other addresses configured. Any
119
authenticated client is then given the pre-encrypted password
120
for that specific client.
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.
125
153
<refsect1 id="purpose">
126
154
<title>PURPOSE</title>
129
156
The purpose of this is to enable <emphasis>remote and unattended
130
rebooting</emphasis> of any client host computer with an
131
<emphasis>encrypted root file system</emphasis>. The client
132
host computer should start a Mandos client in the initial RAM
133
disk environment, the Mandos client program communicates with
134
this server program to get an encrypted password, which is then
135
decrypted and used to unlock the encrypted root file system.
136
The client host computer can then continue its boot sequence
157
rebooting</emphasis> of client host computer with an
158
<emphasis>encrypted root file system</emphasis>. See <xref
159
linkend="overview"/> for details.
142
163
<refsect1 id="options">
143
164
<title>OPTIONS</title>
147
<term><literal>-h</literal>, <literal>--help</literal></term>
167
<term><option>--help</option></term>
168
<term><option>-h</option></term>
150
171
Show a help message and exit
156
<term><literal>-i</literal>, <literal>--interface <replaceable>
157
IF</replaceable></literal></term>
160
Only announce the server and listen to requests on network
161
interface <replaceable>IF</replaceable>. Default is to
162
use all available interfaces.
168
<term><literal>-a</literal>, <literal>--address <replaceable>
169
ADDRESS</replaceable></literal></term>
172
If this option is used, the server will only listen to a
173
specific address. This must currently be an IPv6 address;
174
an IPv4 address can be specified using the
175
<quote><literal>::FFFF:192.0.2.3</literal></quote> syntax.
176
Also, if a link-local address is specified, an interface
177
should be set, since a link-local address is only valid on
178
a single interface. By default, the server will listen to
179
all available addresses.
185
<term><literal>-p</literal>, <literal>--port <replaceable>
186
PORT</replaceable></literal></term>
189
If this option is used, the server to bind to that
190
port. By default, the server will listen to an arbitrary
191
port given by the operating system.
197
<term><literal>--check</literal></term>
200
Run the server's self-tests. This includes any unit
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>
210
Run the server’s self-tests. This includes any unit
207
<term><literal>--debug</literal></term>
210
If the server is run in debug mode, it will run in the
211
foreground and print a lot of debugging information. The
212
default is <emphasis>not</emphasis> to run in debug mode.
218
<term><literal>--priority <replaceable>
219
PRIORITY</replaceable></literal></term>
222
GnuTLS priority string for the TLS handshake with the
224
<citerefentry><refentrytitle>gnutls_priority_init
225
</refentrytitle><manvolnum>3</manvolnum></citerefentry>
226
for the syntax. The default is
227
<quote><literal>SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP</literal></quote>.
228
<emphasis>Warning</emphasis>: changing this may make the
229
TLS handshake fail, making communication with clients
236
<term><literal>--servicename <replaceable>NAME</replaceable>
240
Zeroconf service name. The default is
241
<quote><literal>Mandos</literal></quote>. You only need
242
to change this if you for some reason want to run more
243
than one server on the same <emphasis>host</emphasis>,
244
which would not normally be useful. If there are name
245
collisions on the same <emphasis>network</emphasis>, the
246
newer server will automatically rename itself to
247
<quote><literal>Mandos #2</literal></quote>, and so on,
248
therefore this option is not needed in that case.
254
<term><literal>--configdir <replaceable>DIR</replaceable>
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>
258
263
Directory to search for configuration files. Default is
334
408
</tbody></tgroup></table>
337
411
<refsect1 id="checking">
338
412
<title>CHECKING</title>
340
414
The server will, by default, continually check that the clients
341
415
are still up. If a client has not been confirmed as being up
342
416
for some time, the client is assumed to be compromised and is no
343
longer eligible to receive the encrypted password. The timeout,
344
checker program and interval between checks can be configured
345
both globally and per client; see <citerefentry>
346
<refentrytitle>mandos.conf</refentrytitle>
347
<manvolnum>5</manvolnum></citerefentry> and <citerefentry>
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>
422
<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>
348
433
<refentrytitle>mandos-clients.conf</refentrytitle>
349
<manvolnum>5</manvolnum></citerefentry>.
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.
353
446
<refsect1 id="logging">
354
447
<title>LOGGING</title>
356
The server will send log messaged with various severity levels
357
to <filename>/dev/log</filename>. With the
449
The server will send log message with various severity levels to
450
<filename class="devicefile">/dev/log</filename>. With the
358
451
<option>--debug</option> option, it will log even more messages,
359
452
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>.
363
478
<refsect1 id="exit_status">
364
479
<title>EXIT STATUS</title>
457
624
<!-- do not wrap this line -->
458
<userinput>mandos --interface eth7 --address fe80::aede:48ff:fe71:f6f2</userinput>
625
<userinput>&COMMANDNAME; --interface eth7 --address fe80::aede:48ff:fe71:f6f2</userinput>
461
628
</informalexample>
464
631
<refsect1 id="security">
465
632
<title>SECURITY</title>
633
<refsect2 id="server">
467
634
<title>SERVER</title>
469
Running the server should not in itself present any security
470
risk to the host computer running it.
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
642
<refsect2 id="clients">
474
643
<title>CLIENTS</title>
476
645
The server only gives out its stored data to clients which
477
does have the OpenPGP key of the stored fingerprint. This is
478
guaranteed by the fact that the client sends its OpenPGP
479
public key in the TLS handshake; this ensures it to be
480
genuine. The server computes the fingerprint of the key
481
itself and looks up the fingerprint in its list of
482
clients. The <filename>clients.conf</filename> file (see
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>
483
652
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
484
<manvolnum>5</manvolnum></citerefentry>) must be non-readable
485
by anyone except the user running the server.
653
<manvolnum>5</manvolnum></citerefentry>)
654
<emphasis>must</emphasis> be made non-readable by anyone
655
except the user starting the server (usually root).
658
As detailed in <xref linkend="checking"/>, the status of all
659
client computers will continually be checked and be assumed
660
compromised if they are gone for too long.
488
663
For more details on client-side security, see
489
<citerefentry><refentrytitle>password-request</refentrytitle>
664
<citerefentry><refentrytitle>mandos-client</refentrytitle>
490
665
<manvolnum>8mandos</manvolnum></citerefentry>.
495
670
<refsect1 id="see_also">
496
671
<title>SEE ALSO</title>
497
<itemizedlist spacing="compact">
499
<citerefentry><refentrytitle>password-request</refentrytitle>
500
<manvolnum>8mandos</manvolnum></citerefentry>
504
<citerefentry><refentrytitle>plugin-runner</refentrytitle>
505
<manvolnum>8mandos</manvolnum></citerefentry>
509
<ulink url="http://www.zeroconf.org/">Zeroconf</ulink>
513
<ulink url="http://www.avahi.org/">Avahi</ulink>
518
url="http://www.gnu.org/software/gnutls/">GnuTLS</ulink>
522
<citation>RFC 4880: <citetitle>OpenPGP Message
523
Format</citetitle></citation>
527
<citation>RFC 5081: <citetitle>Using OpenPGP Keys for
528
Transport Layer Security</citetitle></citation>
532
<citation>RFC 4291: <citetitle>IP Version 6 Addressing
533
Architecture</citetitle>, section 2.5.6, Link-Local IPv6
534
Unicast Addresses</citation>
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>
687
<ulink url="http://www.zeroconf.org/">Zeroconf</ulink>
691
Zeroconf is the network protocol standard used by clients
692
for finding this Mandos server on the local network.
698
<ulink url="https://www.avahi.org/">Avahi</ulink>
702
Avahi is the library this server calls to implement
703
Zeroconf service announcements.
709
<ulink url="https://gnutls.org/">GnuTLS</ulink>
713
GnuTLS is the library this server uses to implement TLS for
714
communicating securely with the client, and at the same time
715
confidently get the client’s public key.
721
RFC 4291: <citetitle>IP Version 6 Addressing
722
Architecture</citetitle>
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
753
RFC 5246: <citetitle>The Transport Layer Security (TLS)
754
Protocol Version 1.2</citetitle>
758
TLS 1.2 is the protocol implemented by GnuTLS.
764
RFC 4880: <citetitle>OpenPGP Message Format</citetitle>
768
The data sent to clients is binary encrypted OpenPGP data.
774
RFC 7250: <citetitle>Using Raw Public Keys in Transport
775
Layer Security (TLS) and Datagram Transport Layer Security
780
This is implemented by GnuTLS version 3.6.6 and is, if
781
present, used by this server so that raw public keys can be
788
RFC 6091: <citetitle>Using OpenPGP Keys for Transport Layer
789
Security (TLS) Authentication</citetitle>
793
This is implemented by GnuTLS before version 3.6.0 and is,
794
if present, used by this server so that OpenPGP keys can be
802
<!-- Local Variables: -->
803
<!-- time-stamp-start: "<!ENTITY TIMESTAMP [\"']" -->
804
<!-- time-stamp-end: "[\"']>" -->
805
<!-- time-stamp-format: "%:y-%02m-%02d" -->