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 VERSION "1.0">
5
<!ENTITY COMMANDNAME "password-request">
6
<!ENTITY TIMESTAMP "2008-09-03">
4
<!ENTITY COMMANDNAME "mandos-client">
5
<!ENTITY TIMESTAMP "2013-10-20">
6
<!ENTITY % common SYSTEM "../common.ent">
9
10
<refentry xmlns:xi="http://www.w3.org/2001/XInclude">
11
12
<title>Mandos Manual</title>
12
<!-- Nwalsh’s docbook scripts use this to generate the footer: -->
13
<!-- NWalsh’s docbook scripts use this to generate the footer: -->
13
14
<productname>Mandos</productname>
14
<productnumber>&VERSION;</productnumber>
15
<productnumber>&version;</productnumber>
15
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
38
<holder>Teddy Hogeborn</holder>
35
39
<holder>Björn Påhlsson</holder>
37
41
<xi:include href="../legalnotice.xml"/>
41
45
<refentrytitle>&COMMANDNAME;</refentrytitle>
42
46
<manvolnum>8mandos</manvolnum>
46
50
<refname><command>&COMMANDNAME;</command></refname>
52
Client for <application>Mandos</application>
54
58
<command>&COMMANDNAME;</command>
56
60
<arg choice="plain"><option>--connect
57
<replaceable>IPADDR</replaceable><literal>:</literal
61
<replaceable>ADDRESS</replaceable><literal>:</literal
58
62
><replaceable>PORT</replaceable></option></arg>
59
63
<arg choice="plain"><option>-c
60
<replaceable>IPADDR</replaceable><literal>:</literal
64
<replaceable>ADDRESS</replaceable><literal>:</literal
61
65
><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>
72
69
<arg choice="plain"><option>--interface
73
<replaceable>NAME</replaceable></option></arg>
74
<arg choice="plain"><option>-i
75
<replaceable>NAME</replaceable></option></arg>
70
<replaceable>NAME</replaceable><arg rep='repeat'
71
>,<replaceable>NAME</replaceable></arg></option></arg>
72
<arg choice="plain"><option>-i <replaceable>NAME</replaceable
73
><arg rep='repeat'>,<replaceable>NAME</replaceable></arg
122
134
</refsynopsisdiv>
124
136
<refsect1 id="description">
125
137
<title>DESCRIPTION</title>
127
139
<command>&COMMANDNAME;</command> is a client program that
128
140
communicates with <citerefentry><refentrytitle
129
141
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>
130
to get a password. It uses IPv6 link-local addresses to get
131
network connectivity, Zeroconf to find servers, and TLS with an
132
OpenPGP key to ensure authenticity and confidentiality. It
133
keeps running, trying all servers on the network, until it
134
receives a satisfactory reply or a TERM signal is recieved.
142
to get a password. In slightly more detail, this client program
143
brings up network interfaces, uses the interfaces’ IPv6
144
link-local addresses to get network connectivity, uses Zeroconf
145
to find servers on the local network, and communicates with
146
servers using TLS with an OpenPGP key to ensure authenticity and
147
confidentiality. This client program keeps running, trying all
148
servers on the network, until it receives a satisfactory reply
149
or a TERM signal. After all servers have been tried, all
150
servers are periodically retried. If no servers are found it
151
will wait indefinitely for new servers to appear.
154
The network interfaces are selected like this: If any interfaces
155
are specified using the <option>--interface</option> option,
156
those interface are used. Otherwise,
157
<command>&COMMANDNAME;</command> will use all interfaces that
158
are not loopback interfaces, are not point-to-point interfaces,
159
are capable of broadcasting and do not have the NOARP flag (see
160
<citerefentry><refentrytitle>netdevice</refentrytitle>
161
<manvolnum>7</manvolnum></citerefentry>). (If the
162
<option>--connect</option> option is used, point-to-point
163
interfaces and non-broadcast interfaces are accepted.) If any
164
used interfaces are not up and running, they are first taken up
165
(and later taken down again on program exit).
168
Before network interfaces are selected, all <quote>network
169
hooks</quote> are run; see <xref linkend="network-hooks"/>.
137
172
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).
210
<term><option>--interface=
211
<replaceable>NAME</replaceable></option></term>
229
<term><option>--interface=<replaceable
230
>NAME</replaceable><arg rep='repeat'>,<replaceable
231
>NAME</replaceable></arg></option></term>
213
<replaceable>NAME</replaceable></option></term>
233
<replaceable>NAME</replaceable><arg rep='repeat'>,<replaceable
234
>NAME</replaceable></arg></option></term>
216
Network interface that will be brought up and scanned for
217
Mandos servers to connect to. The default it
218
<quote><literal>eth0</literal></quote>.
221
If the <option>--connect</option> option is used, this
222
specifies the interface to use to connect to the address
237
Comma separated list of network interfaces that will be
238
brought up and scanned for Mandos servers to connect to.
239
The default is the empty string, which will automatically
240
use all appropriate interfaces.
243
If the <option>--connect</option> option is used, and
244
exactly one interface name is specified (except
245
<quote><literal>none</literal></quote>), this specifies
246
the interface to use to connect to the address given.
249
Note that since this program will normally run in the
250
initial RAM disk environment, the interface must be an
251
interface which exists at that stage. Thus, the interface
252
can normally not be a pseudo-interface such as
253
<quote>br0</quote> or <quote>tun0</quote>; such interfaces
254
will not exist until much later in the boot process, and
255
can not be used by this program, unless created by a
256
<quote>network hook</quote> — see <xref
257
linkend="network-hooks"/>.
260
<replaceable>NAME</replaceable> can be the string
261
<quote><literal>none</literal></quote>; this will make
262
<command>&COMMANDNAME;</command> not bring up
263
<emphasis>any</emphasis> interfaces specified
264
<emphasis>after</emphasis> this string. This is not
265
recommended, and only meant for advanced users.
319
<term><option>--delay=<replaceable
320
>SECONDS</replaceable></option></term>
323
After bringing a network interface up, the program waits
324
for the interface to arrive in a <quote>running</quote>
325
state before proceeding. During this time, the kernel log
326
level will be lowered to reduce clutter on the system
327
console, alleviating any other plugins which might be
328
using the system console. This option sets the upper
329
limit of seconds to wait. The default is 2.5 seconds.
335
<term><option>--retry=<replaceable
336
>SECONDS</replaceable></option></term>
339
All Mandos servers are tried repeatedly until a password
340
is received. This value specifies, in seconds, how long
341
between each successive try <emphasis>for the same
342
server</emphasis>. The default is 10 seconds.
348
<term><option>--network-hook-dir=<replaceable
349
>DIR</replaceable></option></term>
352
Network hook directory. The default directory is
353
<quote><filename class="directory"
354
>/lib/mandos/network-hooks.d</filename></quote>.
279
360
<term><option>--debug</option></term>
336
417
<filename>/etc/crypttab</filename>, but it would then be
337
418
impossible to enter a password for the encrypted root disk at
338
419
the console, since this program does not read from the console
339
at all. This is why a separate plugin (<citerefentry>
420
at all. This is why a separate plugin runner (<citerefentry>
421
<refentrytitle>plugin-runner</refentrytitle>
422
<manvolnum>8mandos</manvolnum></citerefentry>) is used to run
423
both this program and others in in parallel,
424
<emphasis>one</emphasis> of which (<citerefentry>
340
425
<refentrytitle>password-prompt</refentrytitle>
341
<manvolnum>8mandos</manvolnum></citerefentry>) does that, which
342
will be run in parallell to this one by the plugin runner.
426
<manvolnum>8mandos</manvolnum></citerefentry>) will prompt for
427
passwords on the system console.
454
<refsect1 id="network-hooks">
455
<title>NETWORK HOOKS</title>
457
If a network interface like a bridge or tunnel is required to
458
find a Mandos server, this requires the interface to be up and
459
running before <command>&COMMANDNAME;</command> starts looking
460
for Mandos servers. This can be accomplished by creating a
461
<quote>network hook</quote> program, and placing it in a special
465
Before the network is used (and again before program exit), any
466
runnable programs found in the network hook directory are run
467
with the argument <quote><literal>start</literal></quote> or
468
<quote><literal>stop</literal></quote>. This should bring up or
469
down, respectively, any network interface which
470
<command>&COMMANDNAME;</command> should use.
472
<refsect2 id="hook-requirements">
473
<title>REQUIREMENTS</title>
475
A network hook must be an executable file, and its name must
476
consist entirely of upper and lower case letters, digits,
477
underscores, periods, and hyphens.
480
A network hook will receive one argument, which can be one of
485
<term><literal>start</literal></term>
488
This should make the network hook create (if necessary)
489
and bring up a network interface.
494
<term><literal>stop</literal></term>
497
This should make the network hook take down a network
498
interface, and delete it if it did not exist previously.
503
<term><literal>files</literal></term>
506
This should make the network hook print, <emphasis>one
507
file per line</emphasis>, all the files needed for it to
508
run. (These files will be copied into the initial RAM
509
filesystem.) Typical use is for a network hook which is
510
a shell script to print its needed binaries.
513
It is not necessary to print any non-executable files
514
already in the network hook directory, these will be
515
copied implicitly if they otherwise satisfy the name
521
<term><literal>modules</literal></term>
524
This should make the network hook print, <emphasis>on
525
separate lines</emphasis>, all the kernel modules needed
526
for it to run. (These modules will be copied into the
527
initial RAM filesystem.) For instance, a tunnel
529
<quote><literal>tun</literal></quote> module.
535
The network hook will be provided with a number of environment
540
<term><envar>MANDOSNETHOOKDIR</envar></term>
543
The network hook directory, specified to
544
<command>&COMMANDNAME;</command> by the
545
<option>--network-hook-dir</option> option. Note: this
546
should <emphasis>always</emphasis> be used by the
547
network hook to refer to itself or any files in the hook
548
directory it may require.
553
<term><envar>DEVICE</envar></term>
556
The network interfaces, as specified to
557
<command>&COMMANDNAME;</command> by the
558
<option>--interface</option> option, combined to one
559
string and separated by commas. If this is set, and
560
does not contain the interface a hook will bring up,
561
there is no reason for a hook to continue.
566
<term><envar>MODE</envar></term>
569
This will be the same as the first argument;
570
i.e. <quote><literal>start</literal></quote>,
571
<quote><literal>stop</literal></quote>,
572
<quote><literal>files</literal></quote>, or
573
<quote><literal>modules</literal></quote>.
578
<term><envar>VERBOSITY</envar></term>
581
This will be the <quote><literal>1</literal></quote> if
582
the <option>--debug</option> option is passed to
583
<command>&COMMANDNAME;</command>, otherwise
584
<quote><literal>0</literal></quote>.
589
<term><envar>DELAY</envar></term>
592
This will be the same as the <option>--delay</option>
593
option passed to <command>&COMMANDNAME;</command>. Is
594
only set if <envar>MODE</envar> is
595
<quote><literal>start</literal></quote> or
596
<quote><literal>stop</literal></quote>.
601
<term><envar>CONNECT</envar></term>
604
This will be the same as the <option>--connect</option>
605
option passed to <command>&COMMANDNAME;</command>. Is
606
only set if <option>--connect</option> is passed and
607
<envar>MODE</envar> is
608
<quote><literal>start</literal></quote> or
609
<quote><literal>stop</literal></quote>.
615
A hook may not read from standard input, and should be
616
restrictive in printing to standard output or standard error
617
unless <varname>VERBOSITY</varname> is
618
<quote><literal>1</literal></quote>.
623
<refsect1 id="files">
370
624
<title>FILES</title>
420
686
</informalexample>
421
687
<informalexample>
423
Run in debug mode, and use a custom key directory:
689
Run in debug mode, and use a custom key:
426
<!-- do not wrap this line -->
427
<userinput>&COMMANDNAME; --debug --keydir keydir</userinput>
693
<!-- do not wrap this line -->
694
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt</userinput>
429
697
</informalexample>
430
698
<informalexample>
432
Run in debug mode, with a custom key directory, and do not use
433
Zeroconf to locate a server; connect directly to the IPv6
700
Run in debug mode, with a custom key, and do not use Zeroconf
701
to locate a server; connect directly to the IPv6 link-local
434
702
address <quote><systemitem class="ipaddress"
435
>2001:db8:f983:bd0b:30de:ae4a:71f2:f672</systemitem></quote>,
436
port 4711, using interface eth2:
703
>fe80::aede:48ff:fe71:f6f2</systemitem></quote>, port 4711,
704
using interface eth2:
440
708
<!-- do not wrap this line -->
441
<userinput>&COMMANDNAME; --debug --keydir keydir --connect 2001:db8:f983:bd0b:30de:ae4a:71f2:f672:4711 --interface eth2</userinput>
709
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt --connect fe80::aede:48ff:fe71:f6f2:4711 --interface eth2</userinput>
444
712
</informalexample>
447
715
<refsect1 id="security">
448
716
<title>SECURITY</title>
469
737
The only remaining weak point is that someone with physical
470
738
access to the client hard drive might turn off the client
471
739
computer, read the OpenPGP keys directly from the hard drive,
472
and communicate with the server. The defense against this is
473
that the server is supposed to notice the client disappearing
474
and will stop giving out the encrypted data. Therefore, it is
475
important to set the timeout and checker interval values tightly
476
on the server. See <citerefentry><refentrytitle
740
and communicate with the server. To safeguard against this, the
741
server is supposed to notice the client disappearing and stop
742
giving out the encrypted data. Therefore, it is important to
743
set the timeout and checker interval values tightly on the
744
server. See <citerefentry><refentrytitle
477
745
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>.