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 "2014-01-20">
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
184
219
assumed to separate the address from the port number.
187
This option is normally only useful for testing and
222
Normally, Zeroconf would be used to locate Mandos servers,
223
in which case this option would only be used when testing
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>
230
<term><option>--interface=<replaceable
231
>NAME</replaceable><arg rep='repeat'>,<replaceable
232
>NAME</replaceable></arg></option></term>
213
<replaceable>NAME</replaceable></option></term>
234
<replaceable>NAME</replaceable><arg rep='repeat'>,<replaceable
235
>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
238
Comma separated list of network interfaces that will be
239
brought up and scanned for Mandos servers to connect to.
240
The default is the empty string, which will automatically
241
use all appropriate interfaces.
244
If the <option>--connect</option> option is used, and
245
exactly one interface name is specified (except
246
<quote><literal>none</literal></quote>), this specifies
247
the interface to use to connect to the address given.
250
Note that since this program will normally run in the
251
initial RAM disk environment, the interface must be an
252
interface which exists at that stage. Thus, the interface
253
can normally not be a pseudo-interface such as
254
<quote>br0</quote> or <quote>tun0</quote>; such interfaces
255
will not exist until much later in the boot process, and
256
can not be used by this program, unless created by a
257
<quote>network hook</quote> — see <xref
258
linkend="network-hooks"/>.
261
<replaceable>NAME</replaceable> can be the string
262
<quote><literal>none</literal></quote>; this will make
263
<command>&COMMANDNAME;</command> not bring up
264
<emphasis>any</emphasis> interfaces specified
265
<emphasis>after</emphasis> this string. This is not
266
recommended, and only meant for advanced users.
320
<term><option>--delay=<replaceable
321
>SECONDS</replaceable></option></term>
324
After bringing a network interface up, the program waits
325
for the interface to arrive in a <quote>running</quote>
326
state before proceeding. During this time, the kernel log
327
level will be lowered to reduce clutter on the system
328
console, alleviating any other plugins which might be
329
using the system console. This option sets the upper
330
limit of seconds to wait. The default is 2.5 seconds.
336
<term><option>--retry=<replaceable
337
>SECONDS</replaceable></option></term>
340
All Mandos servers are tried repeatedly until a password
341
is received. This value specifies, in seconds, how long
342
between each successive try <emphasis>for the same
343
server</emphasis>. The default is 10 seconds.
349
<term><option>--network-hook-dir=<replaceable
350
>DIR</replaceable></option></term>
353
Network hook directory. The default directory is
354
<quote><filename class="directory"
355
>/lib/mandos/network-hooks.d</filename></quote>.
279
361
<term><option>--debug</option></term>
336
418
<filename>/etc/crypttab</filename>, but it would then be
337
419
impossible to enter a password for the encrypted root disk at
338
420
the console, since this program does not read from the console
339
at all. This is why a separate plugin (<citerefentry>
421
at all. This is why a separate plugin runner (<citerefentry>
422
<refentrytitle>plugin-runner</refentrytitle>
423
<manvolnum>8mandos</manvolnum></citerefentry>) is used to run
424
both this program and others in in parallel,
425
<emphasis>one</emphasis> of which (<citerefentry>
340
426
<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.
427
<manvolnum>8mandos</manvolnum></citerefentry>) will prompt for
428
passwords on the system console.
455
<refsect1 id="network-hooks">
456
<title>NETWORK HOOKS</title>
458
If a network interface like a bridge or tunnel is required to
459
find a Mandos server, this requires the interface to be up and
460
running before <command>&COMMANDNAME;</command> starts looking
461
for Mandos servers. This can be accomplished by creating a
462
<quote>network hook</quote> program, and placing it in a special
466
Before the network is used (and again before program exit), any
467
runnable programs found in the network hook directory are run
468
with the argument <quote><literal>start</literal></quote> or
469
<quote><literal>stop</literal></quote>. This should bring up or
470
down, respectively, any network interface which
471
<command>&COMMANDNAME;</command> should use.
473
<refsect2 id="hook-requirements">
474
<title>REQUIREMENTS</title>
476
A network hook must be an executable file, and its name must
477
consist entirely of upper and lower case letters, digits,
478
underscores, periods, and hyphens.
481
A network hook will receive one argument, which can be one of
486
<term><literal>start</literal></term>
489
This should make the network hook create (if necessary)
490
and bring up a network interface.
495
<term><literal>stop</literal></term>
498
This should make the network hook take down a network
499
interface, and delete it if it did not exist previously.
504
<term><literal>files</literal></term>
507
This should make the network hook print, <emphasis>one
508
file per line</emphasis>, all the files needed for it to
509
run. (These files will be copied into the initial RAM
510
filesystem.) Typical use is for a network hook which is
511
a shell script to print its needed binaries.
514
It is not necessary to print any non-executable files
515
already in the network hook directory, these will be
516
copied implicitly if they otherwise satisfy the name
522
<term><literal>modules</literal></term>
525
This should make the network hook print, <emphasis>on
526
separate lines</emphasis>, all the kernel modules needed
527
for it to run. (These modules will be copied into the
528
initial RAM filesystem.) For instance, a tunnel
530
<quote><literal>tun</literal></quote> module.
536
The network hook will be provided with a number of environment
541
<term><envar>MANDOSNETHOOKDIR</envar></term>
544
The network hook directory, specified to
545
<command>&COMMANDNAME;</command> by the
546
<option>--network-hook-dir</option> option. Note: this
547
should <emphasis>always</emphasis> be used by the
548
network hook to refer to itself or any files in the hook
549
directory it may require.
554
<term><envar>DEVICE</envar></term>
557
The network interfaces, as specified to
558
<command>&COMMANDNAME;</command> by the
559
<option>--interface</option> option, combined to one
560
string and separated by commas. If this is set, and
561
does not contain the interface a hook will bring up,
562
there is no reason for a hook to continue.
567
<term><envar>MODE</envar></term>
570
This will be the same as the first argument;
571
i.e. <quote><literal>start</literal></quote>,
572
<quote><literal>stop</literal></quote>,
573
<quote><literal>files</literal></quote>, or
574
<quote><literal>modules</literal></quote>.
579
<term><envar>VERBOSITY</envar></term>
582
This will be the <quote><literal>1</literal></quote> if
583
the <option>--debug</option> option is passed to
584
<command>&COMMANDNAME;</command>, otherwise
585
<quote><literal>0</literal></quote>.
590
<term><envar>DELAY</envar></term>
593
This will be the same as the <option>--delay</option>
594
option passed to <command>&COMMANDNAME;</command>. Is
595
only set if <envar>MODE</envar> is
596
<quote><literal>start</literal></quote> or
597
<quote><literal>stop</literal></quote>.
602
<term><envar>CONNECT</envar></term>
605
This will be the same as the <option>--connect</option>
606
option passed to <command>&COMMANDNAME;</command>. Is
607
only set if <option>--connect</option> is passed and
608
<envar>MODE</envar> is
609
<quote><literal>start</literal></quote> or
610
<quote><literal>stop</literal></quote>.
616
A hook may not read from standard input, and should be
617
restrictive in printing to standard output or standard error
618
unless <varname>VERBOSITY</varname> is
619
<quote><literal>1</literal></quote>.
624
<refsect1 id="files">
370
625
<title>FILES</title>
420
687
</informalexample>
421
688
<informalexample>
423
Run in debug mode, and use a custom key directory:
690
Run in debug mode, and use a custom key:
426
<!-- do not wrap this line -->
427
<userinput>&COMMANDNAME; --debug --keydir keydir</userinput>
694
<!-- do not wrap this line -->
695
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt</userinput>
429
698
</informalexample>
430
699
<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
701
Run in debug mode, with a custom key, and do not use Zeroconf
702
to locate a server; connect directly to the IPv6 link-local
434
703
address <quote><systemitem class="ipaddress"
435
>2001:db8:f983:bd0b:30de:ae4a:71f2:f672</systemitem></quote>,
436
port 4711, using interface eth2:
704
>fe80::aede:48ff:fe71:f6f2</systemitem></quote>, port 4711,
705
using interface eth2:
440
709
<!-- do not wrap this line -->
441
<userinput>&COMMANDNAME; --debug --keydir keydir --connect 2001:db8:f983:bd0b:30de:ae4a:71f2:f672:4711 --interface eth2</userinput>
710
<userinput>&COMMANDNAME; --debug --pubkey keydir/pubkey.txt --seckey keydir/seckey.txt --connect fe80::aede:48ff:fe71:f6f2:4711 --interface eth2</userinput>
444
713
</informalexample>
447
716
<refsect1 id="security">
448
717
<title>SECURITY</title>
469
738
The only remaining weak point is that someone with physical
470
739
access to the client hard drive might turn off the client
471
740
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
741
and communicate with the server. To safeguard against this, the
742
server is supposed to notice the client disappearing and stop
743
giving out the encrypted data. Therefore, it is important to
744
set the timeout and checker interval values tightly on the
745
server. See <citerefentry><refentrytitle
477
746
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>.