48
68
<refname><command>&COMMANDNAME;</command></refname>
50
Gives encrypted passwords to authenticated Mandos clients
70
Sends encrypted passwords to authenticated Mandos clients
56
76
<command>&COMMANDNAME;</command>
58
<arg choice="plain"><option>--interface
59
<replaceable>NAME</replaceable></option></arg>
60
<arg choice="plain"><option>-i
61
<replaceable>NAME</replaceable></option></arg>
65
<arg choice="plain"><option>--address
66
<replaceable>ADDRESS</replaceable></option></arg>
67
<arg choice="plain"><option>-a
68
<replaceable>ADDRESS</replaceable></option></arg>
72
<arg choice="plain"><option>--port
73
<replaceable>PORT</replaceable></option></arg>
74
<arg choice="plain"><option>-p
75
<replaceable>PORT</replaceable></option></arg>
78
<arg><option>--priority
79
<replaceable>PRIORITY</replaceable></option></arg>
81
<arg><option>--servicename
82
<replaceable>NAME</replaceable></option></arg>
84
<arg><option>--configdir
85
<replaceable>DIRECTORY</replaceable></option></arg>
87
<arg><option>--debug</option></arg>
89
<arg><option>--no-ipv6</option></arg>
92
<command>&COMMANDNAME;</command>
94
<arg choice="plain"><option>--help</option></arg>
95
<arg choice="plain"><option>-h</option></arg>
99
<command>&COMMANDNAME;</command>
100
<arg choice="plain"><option>--version</option></arg>
103
<command>&COMMANDNAME;</command>
104
<arg choice="plain"><option>--check</option></arg>
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>
106
107
</refsynopsisdiv>
108
109
<refsect1 id="description">
109
110
<title>DESCRIPTION</title>
111
112
<command>&COMMANDNAME;</command> is a server daemon which
112
113
handles incoming request for passwords for a pre-defined list of
113
114
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.
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.
124
125
<refsect1 id="purpose">
125
126
<title>PURPOSE</title>
127
129
The purpose of this is to enable <emphasis>remote and unattended
128
rebooting</emphasis> of client host computer with an
129
<emphasis>encrypted root file system</emphasis>. See <xref
130
linkend="overview"/> for details.
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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
134
142
<refsect1 id="options">
135
143
<title>OPTIONS</title>
138
<term><option>--help</option></term>
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<term><option>-h</option></term>
147
<term><literal>-h</literal>, <literal>--help</literal></term>
142
150
Show a help message and exit
148
<term><option>--interface</option>
149
<replaceable>NAME</replaceable></term>
150
<term><option>-i</option>
151
<replaceable>NAME</replaceable></term>
153
<xi:include href="mandos-options.xml" xpointer="interface"/>
158
<term><option>--address
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<replaceable>ADDRESS</replaceable></option></term>
161
<replaceable>ADDRESS</replaceable></option></term>
163
<xi:include href="mandos-options.xml" xpointer="address"/>
169
<replaceable>PORT</replaceable></option></term>
171
<replaceable>PORT</replaceable></option></term>
173
<xi:include href="mandos-options.xml" xpointer="port"/>
178
<term><option>--check</option></term>
181
Run the server’s self-tests. This includes any unit
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
188
<term><option>--debug</option></term>
190
<xi:include href="mandos-options.xml" xpointer="debug"/>
195
<term><option>--priority <replaceable>
196
PRIORITY</replaceable></option></term>
198
<xi:include href="mandos-options.xml" xpointer="priority"/>
203
<term><option>--servicename
204
<replaceable>NAME</replaceable></option></term>
206
<xi:include href="mandos-options.xml"
207
xpointer="servicename"/>
212
<term><option>--configdir
213
<replaceable>DIRECTORY</replaceable></option></term>
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>
216
258
Directory to search for configuration files. Default is
411
<term><filename>/bin/sh</filename></term>
414
This is used to start the configured checker command for
415
each client. See <citerefentry>
416
<refentrytitle>mandos-clients.conf</refentrytitle>
417
<manvolnum>5</manvolnum></citerefentry> for details.
424
420
<refsect1 id="bugs">
425
421
<title>BUGS</title>
427
423
This server might, on especially fatal errors, emit a Python
428
424
backtrace. This could be considered a feature.
431
Currently, if a client is declared <quote>invalid</quote> due to
432
having timed out, the server does not record this fact onto
433
permanent storage. This has some security implications, see
434
<xref linkend="clients"/>.
437
There is currently no way of querying the server of the current
438
status of clients, other than analyzing its <systemitem
439
class="service">syslog</systemitem> output.
442
There is no fine-grained control over logging and debug output.
445
Debug mode is conflated with running in the foreground.
448
The console log messages do not show a time stamp.
451
This server does not check the expire time of clients’ OpenPGP
456
<refsect1 id="example">
457
<title>EXAMPLE</title>
428
<refsect1 id="examples">
429
<title>EXAMPLES</title>
458
430
<informalexample>
460
432
Normal invocation needs no options:
463
<userinput>&COMMANDNAME;</userinput>
435
<userinput>mandos</userinput>
465
437
</informalexample>
466
438
<informalexample>
468
Run the server in debug mode, read configuration files from
469
the <filename>~/mandos</filename> directory, and use the
470
Zeroconf service name <quote>Test</quote> to not collide with
471
any other official Mandos server on this host:
440
Run the server in debug mode and read configuration files from
441
the <filename>~/mandos</filename> directory:
475
445
<!-- do not wrap this line -->
476
<userinput>&COMMANDNAME; --debug --configdir ~/mandos --servicename Test</userinput>
446
<userinput>mandos --debug --configdir ~/mandos --servicename Test</userinput>
479
449
</informalexample>
513
481
itself and looks up the fingerprint in its list of
514
482
clients. The <filename>clients.conf</filename> file (see
515
483
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
516
<manvolnum>5</manvolnum></citerefentry>)
517
<emphasis>must</emphasis> be made non-readable by anyone
518
except the user starting the server (usually root).
521
As detailed in <xref linkend="checking"/>, the status of all
522
client computers will continually be checked and be assumed
523
compromised if they are gone for too long.
526
If a client is compromised, its downtime should be duly noted
527
by the server which would therefore declare the client
528
invalid. But if the server was ever restarted, it would
529
re-read its client list from its configuration file and again
530
regard all clients therein as valid, and hence eligible to
531
receive their passwords. Therefore, be careful when
532
restarting servers if it is suspected that a client has, in
533
fact, been compromised by parties who may now be running a
534
fake Mandos client with the keys from the non-encrypted
535
initial <acronym>RAM</acronym> image of the client host. What
536
should be done in that case (if restarting the server program
537
really is necessary) is to stop the server program, edit the
538
configuration file to omit any suspect clients, and restart
484
<manvolnum>5</manvolnum></citerefentry>) must be non-readable
485
by anyone except the user running the server.
542
488
For more details on client-side security, see
543
<citerefentry><refentrytitle>mandos-client</refentrytitle>
489
<citerefentry><refentrytitle>password-request</refentrytitle>
544
490
<manvolnum>8mandos</manvolnum></citerefentry>.
549
495
<refsect1 id="see_also">
550
496
<title>SEE ALSO</title>
553
<refentrytitle>mandos-clients.conf</refentrytitle>
554
<manvolnum>5</manvolnum></citerefentry>, <citerefentry>
555
<refentrytitle>mandos.conf</refentrytitle>
556
<manvolnum>5</manvolnum></citerefentry>, <citerefentry>
557
<refentrytitle>mandos-client</refentrytitle>
558
<manvolnum>8mandos</manvolnum></citerefentry>, <citerefentry>
559
<refentrytitle>sh</refentrytitle><manvolnum>1</manvolnum>
565
<ulink url="http://www.zeroconf.org/">Zeroconf</ulink>
569
Zeroconf is the network protocol standard used by clients
570
for finding this Mandos server on the local network.
576
<ulink url="http://www.avahi.org/">Avahi</ulink>
580
Avahi is the library this server calls to implement
581
Zeroconf service announcements.
587
<ulink url="http://www.gnu.org/software/gnutls/"
592
GnuTLS is the library this server uses to implement TLS for
593
communicating securely with the client, and at the same time
594
confidently get the client’s public OpenPGP key.
600
RFC 4291: <citetitle>IP Version 6 Addressing
601
Architecture</citetitle>
606
<term>Section 2.2: <citetitle>Text Representation of
607
Addresses</citetitle></term>
608
<listitem><para/></listitem>
611
<term>Section 2.5.5.2: <citetitle>IPv4-Mapped IPv6
612
Address</citetitle></term>
613
<listitem><para/></listitem>
616
<term>Section 2.5.6, <citetitle>Link-Local IPv6 Unicast
617
Addresses</citetitle></term>
620
The clients use IPv6 link-local addresses, which are
621
immediately usable since a link-local addresses is
622
automatically assigned to a network interfaces when it
632
RFC 4346: <citetitle>The Transport Layer Security (TLS)
633
Protocol Version 1.1</citetitle>
637
TLS 1.1 is the protocol implemented by GnuTLS.
643
RFC 4880: <citetitle>OpenPGP Message Format</citetitle>
647
The data sent to clients is binary encrypted OpenPGP data.
653
RFC 5081: <citetitle>Using OpenPGP Keys for Transport Layer
658
This is implemented by GnuTLS and used by this server so
659
that OpenPGP keys can be used.
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>
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