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 COMMANDNAME "mandos-client">
5
<!ENTITY TIMESTAMP "2008-10-03">
6
<!ENTITY % common SYSTEM "../common.ent">
4
<!ENTITY VERSION "1.0">
5
<!ENTITY COMMANDNAME "password-request">
6
<!ENTITY TIMESTAMP "2008-09-03">
10
9
<refentry xmlns:xi="http://www.w3.org/2001/XInclude">
12
11
<title>Mandos Manual</title>
13
<!-- NWalsh’s docbook scripts use this to generate the footer: -->
12
<!-- Nwalsh’s docbook scripts use this to generate the footer: -->
14
13
<productname>Mandos</productname>
15
<productnumber>&version;</productnumber>
14
<productnumber>&VERSION;</productnumber>
16
15
<date>&TIMESTAMP;</date>
47
46
<refname><command>&COMMANDNAME;</command></refname>
49
Client for <application>Mandos</application>
55
54
<command>&COMMANDNAME;</command>
57
56
<arg choice="plain"><option>--connect
58
<replaceable>ADDRESS</replaceable><literal>:</literal
57
<replaceable>IPADDR</replaceable><literal>:</literal
59
58
><replaceable>PORT</replaceable></option></arg>
60
59
<arg choice="plain"><option>-c
61
<replaceable>ADDRESS</replaceable><literal>:</literal
60
<replaceable>IPADDR</replaceable><literal>:</literal
62
61
><replaceable>PORT</replaceable></option></arg>
65
<arg choice="plain"><option>--keydir
66
<replaceable>DIRECTORY</replaceable></option></arg>
67
<arg choice="plain"><option>-d
68
<replaceable>DIRECTORY</replaceable></option></arg>
66
72
<arg choice="plain"><option>--interface
67
73
<replaceable>NAME</replaceable></option></arg>
68
74
<arg choice="plain"><option>-i
125
131
network connectivity, Zeroconf to find servers, and TLS with an
126
132
OpenPGP key to ensure authenticity and confidentiality. It
127
133
keeps running, trying all servers on the network, until it
128
receives a satisfactory reply or a TERM signal is received.
134
receives a satisfactory reply or a TERM signal is recieved.
131
137
This program is not meant to be run directly; it is really meant
194
<term><option>--keydir=<replaceable
195
>DIRECTORY</replaceable></option></term>
197
<replaceable>DIRECTORY</replaceable></option></term>
200
Directory to read the OpenPGP key files
201
<filename>pubkey.txt</filename> and
202
<filename>seckey.txt</filename> from. The default is
203
<filename>/conf/conf.d/mandos</filename> (in the initial
204
<acronym>RAM</acronym> disk environment).
188
210
<term><option>--interface=
189
211
<replaceable>NAME</replaceable></option></term>
210
232
<replaceable>FILE</replaceable></option></term>
213
OpenPGP public key file name. The default name is
214
<quote><filename>/conf/conf.d/mandos/pubkey.txt</filename
235
OpenPGP public key file base name. This will be combined
236
with the directory from the <option>--keydir</option>
237
option to form an absolute file name. The default name is
238
<quote><literal>pubkey.txt</literal></quote>.
221
244
<term><option>--seckey=<replaceable
222
245
>FILE</replaceable></option></term>
224
247
<replaceable>FILE</replaceable></option></term>
227
OpenPGP secret key file name. The default name is
228
<quote><filename>/conf/conf.d/mandos/seckey.txt</filename
250
OpenPGP secret key file base name. This will be combined
251
with the directory from the <option>--keydir</option>
252
option to form an absolute file name. The default name is
253
<quote><literal>seckey.txt</literal></quote>.
312
336
<filename>/etc/crypttab</filename>, but it would then be
313
337
impossible to enter a password for the encrypted root disk at
314
338
the console, since this program does not read from the console
315
at all. This is why a separate plugin runner (<citerefentry>
316
<refentrytitle>plugin-runner</refentrytitle>
317
<manvolnum>8mandos</manvolnum></citerefentry>) is used to run
318
both this program and others in in parallel,
319
<emphasis>one</emphasis> of which will prompt for passwords on
339
at all. This is why a separate plugin does that, which will be
340
run in parallell to this one by the plugin runner.
399
418
</informalexample>
400
419
<informalexample>
402
Run in debug mode, and use a custom key:
421
Run in debug mode, and use a custom key directory:
406
<!-- do not wrap this line -->
407
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt</userinput>
424
<!-- do not wrap this line -->
425
<userinput>&COMMANDNAME; --debug --keydir keydir</userinput>
410
427
</informalexample>
411
428
<informalexample>
413
Run in debug mode, with a custom key, and do not use Zeroconf
414
to locate a server; connect directly to the IPv6 address
415
<quote><systemitem class="ipaddress"
430
Run in debug mode, with a custom key directory, and do not use
431
Zeroconf to locate a server; connect directly to the IPv6
432
address <quote><systemitem class="ipaddress"
416
433
>2001:db8:f983:bd0b:30de:ae4a:71f2:f672</systemitem></quote>,
417
434
port 4711, using interface eth2:
421
438
<!-- do not wrap this line -->
422
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt --connect 2001:db8:f983:bd0b:30de:ae4a:71f2:f672:4711 --interface eth2</userinput>
439
<userinput>&COMMANDNAME; --debug --keydir keydir --connect 2001:db8:f983:bd0b:30de:ae4a:71f2:f672:4711 --interface eth2</userinput>
425
442
</informalexample>
428
445
<refsect1 id="security">
429
446
<title>SECURITY</title>
431
448
This program is set-uid to root, but will switch back to the
432
original (and presumably non-privileged) user and group after
433
bringing up the network interface.
449
original user and group after bringing up the network interface.
436
452
To use this program for its intended purpose (see <xref
450
466
The only remaining weak point is that someone with physical
451
467
access to the client hard drive might turn off the client
452
468
computer, read the OpenPGP keys directly from the hard drive,
453
and communicate with the server. To safeguard against this, the
454
server is supposed to notice the client disappearing and stop
455
giving out the encrypted data. Therefore, it is important to
456
set the timeout and checker interval values tightly on the
457
server. See <citerefentry><refentrytitle
469
and communicate with the server. The defense against this is
470
that the server is supposed to notice the client disappearing
471
and will stop giving out the encrypted data. Therefore, it is
472
important to set the timeout and checker interval values tightly
473
on the server. See <citerefentry><refentrytitle
458
474
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
461
It will also help if the checker program on the server is
462
configured to request something from the client which can not be
463
spoofed by someone else on the network, unlike unencrypted
464
<acronym>ICMP</acronym> echo (<quote>ping</quote>) replies.
467
<emphasis>Note</emphasis>: This makes it completely insecure to
468
have <application >Mandos</application> clients which dual-boot
469
to another operating system which is <emphasis>not</emphasis>
470
trusted to keep the initial <acronym>RAM</acronym> disk image
477
<emphasis>Note</emphasis>: This makes it impossible to have
478
<application >Mandos</application> clients which dual-boot to
479
another operating system which does <emphasis>not</emphasis> run
480
a <application>Mandos</application> client.
475
484
<refsect1 id="see_also">
476
485
<title>SEE ALSO</title>
478
<citerefentry><refentrytitle>cryptsetup</refentrytitle>
479
<manvolnum>8</manvolnum></citerefentry>,
480
<citerefentry><refentrytitle>crypttab</refentrytitle>
481
<manvolnum>5</manvolnum></citerefentry>,
482
487
<citerefentry><refentrytitle>mandos</refentrytitle>
483
488
<manvolnum>8</manvolnum></citerefentry>,
484
489
<citerefentry><refentrytitle>password-prompt</refentrytitle>
486
491
<citerefentry><refentrytitle>plugin-runner</refentrytitle>
487
492
<manvolnum>8mandos</manvolnum></citerefentry>
492
<ulink url="http://www.zeroconf.org/">Zeroconf</ulink>
496
Zeroconf is the network protocol standard used for finding
497
Mandos servers on the local network.
503
<ulink url="http://www.avahi.org/">Avahi</ulink>
507
Avahi is the library this program calls to find Zeroconf
514
<ulink url="http://www.gnu.org/software/gnutls/"
519
GnuTLS is the library this client uses to implement TLS for
520
communicating securely with the server, and at the same time
521
send the public OpenPGP key to the server.
527
<ulink url="http://www.gnupg.org/related_software/gpgme/"
532
GPGME is the library used to decrypt the OpenPGP data sent
539
RFC 4291: <citetitle>IP Version 6 Addressing
540
Architecture</citetitle>
545
<term>Section 2.2: <citetitle>Text Representation of
546
Addresses</citetitle></term>
547
<listitem><para/></listitem>
550
<term>Section 2.5.5.2: <citetitle>IPv4-Mapped IPv6
551
Address</citetitle></term>
552
<listitem><para/></listitem>
555
<term>Section 2.5.6, <citetitle>Link-Local IPv6 Unicast
556
Addresses</citetitle></term>
559
This client uses IPv6 link-local addresses, which are
560
immediately usable since a link-local addresses is
561
automatically assigned to a network interfaces when it
571
RFC 4346: <citetitle>The Transport Layer Security (TLS)
572
Protocol Version 1.1</citetitle>
576
TLS 1.1 is the protocol implemented by GnuTLS.
582
RFC 4880: <citetitle>OpenPGP Message Format</citetitle>
586
The data received from the server is binary encrypted
593
RFC 5081: <citetitle>Using OpenPGP Keys for Transport Layer
598
This is implemented by GnuTLS and used by this program so
599
that OpenPGP keys can be used.
496
<ulink url="http://www.zeroconf.org/">Zeroconf</ulink>
500
<ulink url="http://www.avahi.org/">Avahi</ulink>
505
url="http://www.gnu.org/software/gnutls/">GnuTLS</ulink>
510
url="http://www.gnupg.org/related_software/gpgme/"
515
<citation>RFC 4880: <citetitle>OpenPGP Message
516
Format</citetitle></citation>
520
<citation>RFC 5081: <citetitle>Using OpenPGP Keys for
521
Transport Layer Security</citetitle></citation>
525
<citation>RFC 4291: <citetitle>IP Version 6 Addressing
526
Architecture</citetitle>, section 2.5.6, Link-Local IPv6
527
Unicast Addresses</citation>
607
533
<!-- Local Variables: -->
608
534
<!-- time-stamp-start: "<!ENTITY TIMESTAMP [\"']" -->
609
535
<!-- time-stamp-end: "[\"']>" -->