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 "2008-09-04">
4
<!ENTITY COMMANDNAME "mandos-client">
5
<!ENTITY TIMESTAMP "2014-03-01">
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
39
<holder>Teddy Hogeborn</holder>
35
40
<holder>Björn Påhlsson</holder>
37
42
<xi:include href="../legalnotice.xml"/>
41
46
<refentrytitle>&COMMANDNAME;</refentrytitle>
42
47
<manvolnum>8mandos</manvolnum>
115
135
</refsynopsisdiv>
117
137
<refsect1 id="description">
118
138
<title>DESCRIPTION</title>
120
140
<command>&COMMANDNAME;</command> is a client program that
121
141
communicates with <citerefentry><refentrytitle
122
142
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>
123
to get a password. It uses IPv6 link-local addresses to get
124
network connectivity, Zeroconf to find servers, and TLS with an
125
OpenPGP key to ensure authenticity and confidentiality. It
126
keeps running, trying all servers on the network, until it
127
receives a satisfactory reply or a TERM signal is received.
143
to get a password. In slightly more detail, this client program
144
brings up network interfaces, uses the interfaces’ IPv6
145
link-local addresses to get network connectivity, uses Zeroconf
146
to find servers on the local network, and communicates with
147
servers using TLS with an OpenPGP key to ensure authenticity and
148
confidentiality. This client program keeps running, trying all
149
servers on the network, until it receives a satisfactory reply
150
or a TERM signal. After all servers have been tried, all
151
servers are periodically retried. If no servers are found it
152
will wait indefinitely for new servers to appear.
155
The network interfaces are selected like this: If any interfaces
156
are specified using the <option>--interface</option> option,
157
those interface are used. Otherwise,
158
<command>&COMMANDNAME;</command> will use all interfaces that
159
are not loopback interfaces, are not point-to-point interfaces,
160
are capable of broadcasting and do not have the NOARP flag (see
161
<citerefentry><refentrytitle>netdevice</refentrytitle>
162
<manvolnum>7</manvolnum></citerefentry>). (If the
163
<option>--connect</option> option is used, point-to-point
164
interfaces and non-broadcast interfaces are accepted.) If any
165
used interfaces are not up and running, they are first taken up
166
(and later taken down again on program exit).
169
Before network interfaces are selected, all <quote>network
170
hooks</quote> are run; see <xref linkend="network-hooks"/>.
130
173
This program is not meant to be run directly; it is really meant
177
220
assumed to separate the address from the port number.
180
This option is normally only useful for testing and
223
Normally, Zeroconf would be used to locate Mandos servers,
224
in which case this option would only be used when testing
187
<term><option>--interface=
188
<replaceable>NAME</replaceable></option></term>
231
<term><option>--interface=<replaceable
232
>NAME</replaceable><arg rep='repeat'>,<replaceable
233
>NAME</replaceable></arg></option></term>
190
<replaceable>NAME</replaceable></option></term>
235
<replaceable>NAME</replaceable><arg rep='repeat'>,<replaceable
236
>NAME</replaceable></arg></option></term>
193
Network interface that will be brought up and scanned for
194
Mandos servers to connect to. The default it
195
<quote><literal>eth0</literal></quote>.
198
If the <option>--connect</option> option is used, this
199
specifies the interface to use to connect to the address
239
Comma separated list of network interfaces that will be
240
brought up and scanned for Mandos servers to connect to.
241
The default is the empty string, which will automatically
242
use all appropriate interfaces.
245
If the <option>--connect</option> option is used, and
246
exactly one interface name is specified (except
247
<quote><literal>none</literal></quote>), this specifies
248
the interface to use to connect to the address given.
251
Note that since this program will normally run in the
252
initial RAM disk environment, the interface must be an
253
interface which exists at that stage. Thus, the interface
254
can normally not be a pseudo-interface such as
255
<quote>br0</quote> or <quote>tun0</quote>; such interfaces
256
will not exist until much later in the boot process, and
257
can not be used by this program, unless created by a
258
<quote>network hook</quote> — see <xref
259
linkend="network-hooks"/>.
262
<replaceable>NAME</replaceable> can be the string
263
<quote><literal>none</literal></quote>; this will make
264
<command>&COMMANDNAME;</command> not bring up
265
<emphasis>any</emphasis> interfaces specified
266
<emphasis>after</emphasis> this string. This is not
267
recommended, and only meant for advanced users.
321
<term><option>--delay=<replaceable
322
>SECONDS</replaceable></option></term>
325
After bringing a network interface up, the program waits
326
for the interface to arrive in a <quote>running</quote>
327
state before proceeding. During this time, the kernel log
328
level will be lowered to reduce clutter on the system
329
console, alleviating any other plugins which might be
330
using the system console. This option sets the upper
331
limit of seconds to wait. The default is 2.5 seconds.
337
<term><option>--retry=<replaceable
338
>SECONDS</replaceable></option></term>
341
All Mandos servers are tried repeatedly until a password
342
is received. This value specifies, in seconds, how long
343
between each successive try <emphasis>for the same
344
server</emphasis>. The default is 10 seconds.
350
<term><option>--network-hook-dir=<replaceable
351
>DIR</replaceable></option></term>
354
Network hook directory. The default directory is
355
<quote><filename class="directory"
356
>/lib/mandos/network-hooks.d</filename></quote>.
254
362
<term><option>--debug</option></term>
311
419
<filename>/etc/crypttab</filename>, but it would then be
312
420
impossible to enter a password for the encrypted root disk at
313
421
the console, since this program does not read from the console
314
at all. This is why a separate plugin (<citerefentry>
422
at all. This is why a separate plugin runner (<citerefentry>
423
<refentrytitle>plugin-runner</refentrytitle>
424
<manvolnum>8mandos</manvolnum></citerefentry>) is used to run
425
both this program and others in in parallel,
426
<emphasis>one</emphasis> of which (<citerefentry>
315
427
<refentrytitle>password-prompt</refentrytitle>
316
<manvolnum>8mandos</manvolnum></citerefentry>) does that, which
317
will be run in parallel to this one by the plugin runner.
428
<manvolnum>8mandos</manvolnum></citerefentry>) will prompt for
429
passwords on the system console.
456
<refsect1 id="network-hooks">
457
<title>NETWORK HOOKS</title>
459
If a network interface like a bridge or tunnel is required to
460
find a Mandos server, this requires the interface to be up and
461
running before <command>&COMMANDNAME;</command> starts looking
462
for Mandos servers. This can be accomplished by creating a
463
<quote>network hook</quote> program, and placing it in a special
467
Before the network is used (and again before program exit), any
468
runnable programs found in the network hook directory are run
469
with the argument <quote><literal>start</literal></quote> or
470
<quote><literal>stop</literal></quote>. This should bring up or
471
down, respectively, any network interface which
472
<command>&COMMANDNAME;</command> should use.
474
<refsect2 id="hook-requirements">
475
<title>REQUIREMENTS</title>
477
A network hook must be an executable file, and its name must
478
consist entirely of upper and lower case letters, digits,
479
underscores, periods, and hyphens.
482
A network hook will receive one argument, which can be one of
487
<term><literal>start</literal></term>
490
This should make the network hook create (if necessary)
491
and bring up a network interface.
496
<term><literal>stop</literal></term>
499
This should make the network hook take down a network
500
interface, and delete it if it did not exist previously.
505
<term><literal>files</literal></term>
508
This should make the network hook print, <emphasis>one
509
file per line</emphasis>, all the files needed for it to
510
run. (These files will be copied into the initial RAM
511
filesystem.) Typical use is for a network hook which is
512
a shell script to print its needed binaries.
515
It is not necessary to print any non-executable files
516
already in the network hook directory, these will be
517
copied implicitly if they otherwise satisfy the name
523
<term><literal>modules</literal></term>
526
This should make the network hook print, <emphasis>on
527
separate lines</emphasis>, all the kernel modules needed
528
for it to run. (These modules will be copied into the
529
initial RAM filesystem.) For instance, a tunnel
531
<quote><literal>tun</literal></quote> module.
537
The network hook will be provided with a number of environment
542
<term><envar>MANDOSNETHOOKDIR</envar></term>
545
The network hook directory, specified to
546
<command>&COMMANDNAME;</command> by the
547
<option>--network-hook-dir</option> option. Note: this
548
should <emphasis>always</emphasis> be used by the
549
network hook to refer to itself or any files in the hook
550
directory it may require.
555
<term><envar>DEVICE</envar></term>
558
The network interfaces, as specified to
559
<command>&COMMANDNAME;</command> by the
560
<option>--interface</option> option, combined to one
561
string and separated by commas. If this is set, and
562
does not contain the interface a hook will bring up,
563
there is no reason for a hook to continue.
568
<term><envar>MODE</envar></term>
571
This will be the same as the first argument;
572
i.e. <quote><literal>start</literal></quote>,
573
<quote><literal>stop</literal></quote>,
574
<quote><literal>files</literal></quote>, or
575
<quote><literal>modules</literal></quote>.
580
<term><envar>VERBOSITY</envar></term>
583
This will be the <quote><literal>1</literal></quote> if
584
the <option>--debug</option> option is passed to
585
<command>&COMMANDNAME;</command>, otherwise
586
<quote><literal>0</literal></quote>.
591
<term><envar>DELAY</envar></term>
594
This will be the same as the <option>--delay</option>
595
option passed to <command>&COMMANDNAME;</command>. Is
596
only set if <envar>MODE</envar> is
597
<quote><literal>start</literal></quote> or
598
<quote><literal>stop</literal></quote>.
603
<term><envar>CONNECT</envar></term>
606
This will be the same as the <option>--connect</option>
607
option passed to <command>&COMMANDNAME;</command>. Is
608
only set if <option>--connect</option> is passed and
609
<envar>MODE</envar> is
610
<quote><literal>start</literal></quote> or
611
<quote><literal>stop</literal></quote>.
617
A hook may not read from standard input, and should be
618
restrictive in printing to standard output or standard error
619
unless <varname>VERBOSITY</varname> is
620
<quote><literal>1</literal></quote>.
625
<refsect1 id="files">
345
626
<title>FILES</title>
447
739
The only remaining weak point is that someone with physical
448
740
access to the client hard drive might turn off the client
449
741
computer, read the OpenPGP keys directly from the hard drive,
450
and communicate with the server. The defense against this is
451
that the server is supposed to notice the client disappearing
452
and will stop giving out the encrypted data. Therefore, it is
453
important to set the timeout and checker interval values tightly
454
on the server. See <citerefentry><refentrytitle
742
and communicate with the server. To safeguard against this, the
743
server is supposed to notice the client disappearing and stop
744
giving out the encrypted data. Therefore, it is important to
745
set the timeout and checker interval values tightly on the
746
server. See <citerefentry><refentrytitle
455
747
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>.