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
4
<!ENTITY COMMANDNAME "mandos-client">
5
<!ENTITY TIMESTAMP "2017-02-23">
5
<!ENTITY TIMESTAMP "2023-10-21">
6
6
<!ENTITY % common SYSTEM "../common.ent">
94
96
<replaceable>FILE</replaceable></option></arg>
100
<arg choice="plain"><option>--tls-privkey
101
<replaceable>FILE</replaceable></option></arg>
102
<arg choice="plain"><option>-t
103
<replaceable>FILE</replaceable></option></arg>
107
<arg choice="plain"><option>--tls-pubkey
108
<replaceable>FILE</replaceable></option></arg>
109
<arg choice="plain"><option>-T
110
<replaceable>FILE</replaceable></option></arg>
98
114
<option>--priority <replaceable>STRING</replaceable></option>
153
169
brings up network interfaces, uses the interfaces’ IPv6
154
170
link-local addresses to get network connectivity, uses Zeroconf
155
171
to find servers on the local network, and communicates with
156
servers using TLS with an OpenPGP key to ensure authenticity and
157
confidentiality. This client program keeps running, trying all
158
servers on the network, until it receives a satisfactory reply
159
or a TERM signal. After all servers have been tried, all
172
servers using TLS with a raw public key to ensure authenticity
173
and confidentiality. This client program keeps running, trying
174
all servers on the network, until it receives a satisfactory
175
reply or a TERM signal. After all servers have been tried, all
160
176
servers are periodically retried. If no servers are found it
161
177
will wait indefinitely for new servers to appear.
182
198
This program is not meant to be run directly; it is really meant
183
to run as a plugin of the <application>Mandos</application>
184
<citerefentry><refentrytitle>plugin-runner</refentrytitle>
185
<manvolnum>8mandos</manvolnum></citerefentry>, which runs in the
186
initial <acronym>RAM</acronym> disk environment because it is
187
specified as a <quote>keyscript</quote> in the <citerefentry>
188
<refentrytitle>crypttab</refentrytitle><manvolnum>5</manvolnum>
189
</citerefentry> file.
199
to be run by other programs in the initial
200
<acronym>RAM</acronym> disk environment; see <xref
201
linkend="overview"/>.
204
216
<title>OPTIONS</title>
206
218
This program is commonly not invoked from the command line; it
207
is normally started by the <application>Mandos</application>
208
plugin runner, see <citerefentry><refentrytitle
209
>plugin-runner</refentrytitle><manvolnum>8mandos</manvolnum>
210
</citerefentry>. Any command line options this program accepts
211
are therefore normally provided by the plugin runner, and not
219
is normally started by another program as described in <xref
220
linkend="description"/>. Any command line options this program
221
accepts are therefore normally provided by the invoking program,
319
<term><option>--tls-pubkey=<replaceable
320
>FILE</replaceable></option></term>
322
<replaceable>FILE</replaceable></option></term>
325
TLS raw public key file name. The default name is
326
<quote><filename>/conf/conf.d/mandos/tls-pubkey.pem</filename
333
<term><option>--tls-privkey=<replaceable
334
>FILE</replaceable></option></term>
336
<replaceable>FILE</replaceable></option></term>
339
TLS secret key file name. The default name is
340
<quote><filename>/conf/conf.d/mandos/tls-privkey.pem</filename
309
347
<term><option>--priority=<replaceable
310
348
>STRING</replaceable></option></term>
322
360
Sets the number of bits to use for the prime number in the
323
361
TLS Diffie-Hellman key exchange. The default value is
324
selected automatically based on the OpenPGP key. Note
325
that if the <option>--dh-params</option> option is used,
326
the values from that file will be used instead.
362
selected automatically based on the GnuTLS security
363
profile set in its priority string. Note that if the
364
<option>--dh-params</option> option is used, the values
365
from that file will be used instead.
437
476
<title>OVERVIEW</title>
438
477
<xi:include href="../overview.xml"/>
440
This program is the client part. It is a plugin started by
441
<citerefentry><refentrytitle>plugin-runner</refentrytitle>
442
<manvolnum>8mandos</manvolnum></citerefentry> which will run in
443
an initial <acronym>RAM</acronym> disk environment.
479
This program is the client part. It is run automatically in an
480
initial <acronym>RAM</acronym> disk environment.
483
In an initial <acronym>RAM</acronym> disk environment using
484
<citerefentry><refentrytitle>systemd</refentrytitle>
485
<manvolnum>1</manvolnum></citerefentry>, this program is started
486
by the <application>Mandos</application> <citerefentry>
487
<refentrytitle>password-agent</refentrytitle>
488
<manvolnum>8mandos</manvolnum></citerefentry>, which in turn is
489
started automatically by the <citerefentry>
490
<refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum>
491
</citerefentry> <quote>Password Agent</quote> system.
494
In the case of a non-<citerefentry>
495
<refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum>
496
</citerefentry> environment, this program is started as a plugin
497
of the <application>Mandos</application> <citerefentry>
498
<refentrytitle>plugin-runner</refentrytitle>
499
<manvolnum>8mandos</manvolnum></citerefentry>, which runs in the
500
initial <acronym>RAM</acronym> disk environment because it is
501
specified as a <quote>keyscript</quote> in the <citerefentry>
502
<refentrytitle>crypttab</refentrytitle><manvolnum>5</manvolnum>
503
</citerefentry> file.
446
506
This program could, theoretically, be used as a keyscript in
447
507
<filename>/etc/crypttab</filename>, but it would then be
448
508
impossible to enter a password for the encrypted root disk at
449
509
the console, since this program does not read from the console
450
at all. This is why a separate plugin runner (<citerefentry>
451
<refentrytitle>plugin-runner</refentrytitle>
452
<manvolnum>8mandos</manvolnum></citerefentry>) is used to run
453
both this program and others in in parallel,
454
<emphasis>one</emphasis> of which (<citerefentry>
455
<refentrytitle>password-prompt</refentrytitle>
456
<manvolnum>8mandos</manvolnum></citerefentry>) will prompt for
457
passwords on the system console.
481
534
This environment variable will be assumed to contain the
482
535
directory containing any helper executables. The use and
483
nature of these helper executables, if any, is
484
purposefully not documented.
536
nature of these helper executables, if any, is purposely
737
<term><filename>/conf/conf.d/mandos/tls-pubkey.pem</filename
739
<term><filename>/conf/conf.d/mandos/tls-privkey.pem</filename
743
Public and private raw key files, in <quote>PEM</quote>
744
format. These are the default file names, they can be
745
changed with the <option>--tls-pubkey</option> and
746
<option>--tls-privkey</option> options.
685
752
class="directory">/lib/mandos/network-hooks.d</filename></term>
703
770
<title>EXAMPLE</title>
705
772
Note that normally, command line options will not be given
706
directly, but via options for the Mandos <citerefentry
707
><refentrytitle>plugin-runner</refentrytitle>
708
<manvolnum>8mandos</manvolnum></citerefentry>.
773
directly, but passed on via the program responsible for starting
774
this program; see <xref linkend="overview"/>.
710
776
<informalexample>
728
794
</informalexample>
729
795
<informalexample>
731
Run in debug mode, and use a custom key:
797
Run in debug mode, and use custom keys:
735
801
<!-- do not wrap this line -->
736
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt</userinput>
802
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt --tls-pubkey keydir/tls-pubkey.pem --tls-privkey keydir/tls-privkey.pem</userinput>
739
805
</informalexample>
740
806
<informalexample>
742
Run in debug mode, with a custom key, and do not use Zeroconf
808
Run in debug mode, with custom keys, and do not use Zeroconf
743
809
to locate a server; connect directly to the IPv6 link-local
744
810
address <quote><systemitem class="ipaddress"
745
811
>fe80::aede:48ff:fe71:f6f2</systemitem></quote>, port 4711,
757
823
<refsect1 id="security">
758
824
<title>SECURITY</title>
760
This program is set-uid to root, but will switch back to the
761
original (and presumably non-privileged) user and group after
762
bringing up the network interface.
826
This program assumes that it is set-uid to root, and will switch
827
back to the original (and presumably non-privileged) user and
828
group after bringing up the network interface.
765
831
To use this program for its intended purpose (see <xref
779
845
The only remaining weak point is that someone with physical
780
846
access to the client hard drive might turn off the client
781
computer, read the OpenPGP keys directly from the hard drive,
782
and communicate with the server. To safeguard against this, the
783
server is supposed to notice the client disappearing and stop
784
giving out the encrypted data. Therefore, it is important to
785
set the timeout and checker interval values tightly on the
786
server. See <citerefentry><refentrytitle
847
computer, read the OpenPGP and TLS keys directly from the hard
848
drive, and communicate with the server. To safeguard against
849
this, the server is supposed to notice the client disappearing
850
and stop giving out the encrypted data. Therefore, it is
851
important to set the timeout and checker interval values tightly
852
on the server. See <citerefentry><refentrytitle
787
853
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
813
879
<manvolnum>5</manvolnum></citerefentry>,
814
880
<citerefentry><refentrytitle>mandos</refentrytitle>
815
881
<manvolnum>8</manvolnum></citerefentry>,
816
<citerefentry><refentrytitle>password-prompt</refentrytitle>
882
<citerefentry><refentrytitle>password-agent</refentrytitle>
817
883
<manvolnum>8mandos</manvolnum></citerefentry>,
818
884
<citerefentry><refentrytitle>plugin-runner</refentrytitle>
819
885
<manvolnum>8mandos</manvolnum></citerefentry>
990
RFC 7250: <citetitle>Using Raw Public Keys in Transport
991
Layer Security (TLS) and Datagram Transport Layer Security
996
This is implemented by GnuTLS in version 3.6.6 and is, if
997
present, used by this program so that raw public keys can be
924
1004
RFC 6091: <citetitle>Using OpenPGP Keys for Transport Layer
925
1005
Security</citetitle>
929
This is implemented by GnuTLS and used by this program so
930
that OpenPGP keys can be used.
1009
This is implemented by GnuTLS before version 3.6.0 and is,
1010
if present, used by this program so that OpenPGP keys can be
added
removed
plugins.d/mandos-client.xml
