68
47
<refname><command>&COMMANDNAME;</command></refname>
70
Sends encrypted passwords to authenticated Mandos clients
49
Gives encrypted passwords to authenticated Mandos clients
76
55
<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>
57
<arg choice="plain"><option>--interface
58
<replaceable>NAME</replaceable></option></arg>
59
<arg choice="plain"><option>-i
60
<replaceable>NAME</replaceable></option></arg>
64
<arg choice="plain"><option>--address
65
<replaceable>ADDRESS</replaceable></option></arg>
66
<arg choice="plain"><option>-a
67
<replaceable>ADDRESS</replaceable></option></arg>
71
<arg choice="plain"><option>--port
72
<replaceable>PORT</replaceable></option></arg>
73
<arg choice="plain"><option>-p
74
<replaceable>PORT</replaceable></option></arg>
77
<arg><option>--priority
78
<replaceable>PRIORITY</replaceable></option></arg>
80
<arg><option>--servicename
81
<replaceable>NAME</replaceable></option></arg>
83
<arg><option>--configdir
84
<replaceable>DIRECTORY</replaceable></option></arg>
86
<arg><option>--debug</option></arg>
88
<arg><option>--no-dbus</option></arg>
91
<command>&COMMANDNAME;</command>
93
<arg choice="plain"><option>--help</option></arg>
94
<arg choice="plain"><option>-h</option></arg>
98
<command>&COMMANDNAME;</command>
99
<arg choice="plain"><option>--version</option></arg>
102
<command>&COMMANDNAME;</command>
103
<arg choice="plain"><option>--check</option></arg>
107
105
</refsynopsisdiv>
109
107
<refsect1 id="description">
110
108
<title>DESCRIPTION</title>
112
110
<command>&COMMANDNAME;</command> is a server daemon which
113
111
handles incoming request for passwords for a pre-defined list of
114
112
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.
113
announce itself on the local network, and uses TLS to
114
communicate securely with and to authenticate the clients. The
115
Mandos server uses IPv6 to allow Mandos clients to use IPv6
116
link-local addresses, since the clients will probably not have
117
any other addresses configured (see <xref linkend="overview"/>).
118
Any authenticated client is then given the stored pre-encrypted
119
password for that specific client.
125
123
<refsect1 id="purpose">
126
124
<title>PURPOSE</title>
129
126
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
127
rebooting</emphasis> of client host computer with an
128
<emphasis>encrypted root file system</emphasis>. See <xref
129
linkend="overview"/> for details.
142
133
<refsect1 id="options">
143
134
<title>OPTIONS</title>
147
<term><literal>-h</literal>, <literal>--help</literal></term>
137
<term><option>--help</option></term>
138
<term><option>-h</option></term>
150
141
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
147
<term><option>--interface</option>
148
<replaceable>NAME</replaceable></term>
149
<term><option>-i</option>
150
<replaceable>NAME</replaceable></term>
152
<xi:include href="mandos-options.xml" xpointer="interface"/>
157
<term><option>--address
158
<replaceable>ADDRESS</replaceable></option></term>
160
<replaceable>ADDRESS</replaceable></option></term>
162
<xi:include href="mandos-options.xml" xpointer="address"/>
168
<replaceable>PORT</replaceable></option></term>
170
<replaceable>PORT</replaceable></option></term>
172
<xi:include href="mandos-options.xml" xpointer="port"/>
177
<term><option>--check</option></term>
180
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>
187
<term><option>--debug</option></term>
189
<xi:include href="mandos-options.xml" xpointer="debug"/>
194
<term><option>--priority <replaceable>
195
PRIORITY</replaceable></option></term>
197
<xi:include href="mandos-options.xml" xpointer="priority"/>
202
<term><option>--servicename
203
<replaceable>NAME</replaceable></option></term>
205
<xi:include href="mandos-options.xml"
206
xpointer="servicename"/>
211
<term><option>--configdir
212
<replaceable>DIRECTORY</replaceable></option></term>
258
215
Directory to search for configuration files. Default is
422
<term><filename>/bin/sh</filename></term>
425
This is used to start the configured checker command for
426
each client. See <citerefentry>
427
<refentrytitle>mandos-clients.conf</refentrytitle>
428
<manvolnum>5</manvolnum></citerefentry> for details.
420
435
<refsect1 id="bugs">
421
436
<title>BUGS</title>
423
438
This server might, on especially fatal errors, emit a Python
424
439
backtrace. This could be considered a feature.
442
Currently, if a client is declared <quote>invalid</quote> due to
443
having timed out, the server does not record this fact onto
444
permanent storage. This has some security implications, see
445
<xref linkend="clients"/>.
448
There is currently no way of querying the server of the current
449
status of clients, other than analyzing its <systemitem
450
class="service">syslog</systemitem> output.
453
There is no fine-grained control over logging and debug output.
456
Debug mode is conflated with running in the foreground.
459
The console log messages does not show a time stamp.
462
This server does not check the expire time of clients’ OpenPGP
428
<refsect1 id="examples">
429
<title>EXAMPLES</title>
467
<refsect1 id="example">
468
<title>EXAMPLE</title>
430
469
<informalexample>
432
471
Normal invocation needs no options:
435
<userinput>mandos</userinput>
474
<userinput>&COMMANDNAME;</userinput>
437
476
</informalexample>
438
477
<informalexample>
440
Run the server in debug mode and read configuration files from
441
the <filename>~/mandos</filename> directory:
479
Run the server in debug mode, read configuration files from
480
the <filename>~/mandos</filename> directory, and use the
481
Zeroconf service name <quote>Test</quote> to not collide with
482
any other official Mandos server on this host:
445
486
<!-- do not wrap this line -->
446
<userinput>mandos --debug --configdir ~/mandos --servicename Test</userinput>
487
<userinput>&COMMANDNAME; --debug --configdir ~/mandos --servicename Test</userinput>
449
490
</informalexample>
481
524
itself and looks up the fingerprint in its list of
482
525
clients. The <filename>clients.conf</filename> file (see
483
526
<citerefentry><refentrytitle>mandos-clients.conf</refentrytitle>
484
<manvolnum>5</manvolnum></citerefentry>) must be non-readable
485
by anyone except the user running the server.
527
<manvolnum>5</manvolnum></citerefentry>)
528
<emphasis>must</emphasis> be made non-readable by anyone
529
except the user starting the server (usually root).
532
As detailed in <xref linkend="checking"/>, the status of all
533
client computers will continually be checked and be assumed
534
compromised if they are gone for too long.
537
If a client is compromised, its downtime should be duly noted
538
by the server which would therefore declare the client
539
invalid. But if the server was ever restarted, it would
540
re-read its client list from its configuration file and again
541
regard all clients therein as valid, and hence eligible to
542
receive their passwords. Therefore, be careful when
543
restarting servers if it is suspected that a client has, in
544
fact, been compromised by parties who may now be running a
545
fake Mandos client with the keys from the non-encrypted
546
initial <acronym>RAM</acronym> image of the client host. What
547
should be done in that case (if restarting the server program
548
really is necessary) is to stop the server program, edit the
549
configuration file to omit any suspect clients, and restart
488
553
For more details on client-side security, see
489
<citerefentry><refentrytitle>password-request</refentrytitle>
554
<citerefentry><refentrytitle>mandos-client</refentrytitle>
490
555
<manvolnum>8mandos</manvolnum></citerefentry>.
495
560
<refsect1 id="see_also">
496
561
<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>
564
<refentrytitle>mandos-clients.conf</refentrytitle>
565
<manvolnum>5</manvolnum></citerefentry>, <citerefentry>
566
<refentrytitle>mandos.conf</refentrytitle>
567
<manvolnum>5</manvolnum></citerefentry>, <citerefentry>
568
<refentrytitle>mandos-client</refentrytitle>
569
<manvolnum>8mandos</manvolnum></citerefentry>, <citerefentry>
570
<refentrytitle>sh</refentrytitle><manvolnum>1</manvolnum>
576
<ulink url="http://www.zeroconf.org/">Zeroconf</ulink>
580
Zeroconf is the network protocol standard used by clients
581
for finding this Mandos server on the local network.
587
<ulink url="http://www.avahi.org/">Avahi</ulink>
591
Avahi is the library this server calls to implement
592
Zeroconf service announcements.
598
<ulink url="http://www.gnu.org/software/gnutls/"
603
GnuTLS is the library this server uses to implement TLS for
604
communicating securely with the client, and at the same time
605
confidently get the client’s public OpenPGP key.
611
RFC 4291: <citetitle>IP Version 6 Addressing
612
Architecture</citetitle>
617
<term>Section 2.2: <citetitle>Text Representation of
618
Addresses</citetitle></term>
619
<listitem><para/></listitem>
622
<term>Section 2.5.5.2: <citetitle>IPv4-Mapped IPv6
623
Address</citetitle></term>
624
<listitem><para/></listitem>
627
<term>Section 2.5.6, <citetitle>Link-Local IPv6 Unicast
628
Addresses</citetitle></term>
631
The clients use IPv6 link-local addresses, which are
632
immediately usable since a link-local addresses is
633
automatically assigned to a network interfaces when it
643
RFC 4346: <citetitle>The Transport Layer Security (TLS)
644
Protocol Version 1.1</citetitle>
648
TLS 1.1 is the protocol implemented by GnuTLS.
654
RFC 4880: <citetitle>OpenPGP Message Format</citetitle>
658
The data sent to clients is binary encrypted OpenPGP data.
664
RFC 5081: <citetitle>Using OpenPGP Keys for Transport Layer
669
This is implemented by GnuTLS and used by this server so
670
that OpenPGP keys can be used.
677
<!-- Local Variables: -->
678
<!-- time-stamp-start: "<!ENTITY TIMESTAMP [\"']" -->
679
<!-- time-stamp-end: "[\"']>" -->
680
<!-- time-stamp-format: "%:y-%02m-%02d" -->