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 "2014-01-20">
6
<!ENTITY % common SYSTEM "../common.ent">
4
<!ENTITY VERSION "1.0">
5
<!ENTITY COMMANDNAME "password-request">
6
<!ENTITY TIMESTAMP "2008-09-04">
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>
19
18
<firstname>Björn</firstname>
20
19
<surname>Påhlsson</surname>
22
<email>belorn@recompile.se</email>
21
<email>belorn@fukt.bsnet.se</email>
26
25
<firstname>Teddy</firstname>
27
26
<surname>Hogeborn</surname>
29
<email>teddy@recompile.se</email>
28
<email>teddy@fukt.bsnet.se</email>
38
34
<holder>Teddy Hogeborn</holder>
39
35
<holder>Björn Påhlsson</holder>
41
37
<xi:include href="../legalnotice.xml"/>
45
41
<refentrytitle>&COMMANDNAME;</refentrytitle>
46
42
<manvolnum>8mandos</manvolnum>
134
115
</refsynopsisdiv>
136
117
<refsect1 id="description">
137
118
<title>DESCRIPTION</title>
139
120
<command>&COMMANDNAME;</command> is a client program that
140
121
communicates with <citerefentry><refentrytitle
141
122
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>
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"/>.
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.
172
130
This program is not meant to be run directly; it is really meant
219
177
assumed to separate the address from the port number.
222
Normally, Zeroconf would be used to locate Mandos servers,
223
in which case this option would only be used when testing
180
This option is normally only useful for testing and
230
<term><option>--interface=<replaceable
231
>NAME</replaceable><arg rep='repeat'>,<replaceable
232
>NAME</replaceable></arg></option></term>
187
<term><option>--interface=
188
<replaceable>NAME</replaceable></option></term>
234
<replaceable>NAME</replaceable><arg rep='repeat'>,<replaceable
235
>NAME</replaceable></arg></option></term>
190
<replaceable>NAME</replaceable></option></term>
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.
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
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>.
361
254
<term><option>--debug</option></term>
418
311
<filename>/etc/crypttab</filename>, but it would then be
419
312
impossible to enter a password for the encrypted root disk at
420
313
the console, since this program does not read from the console
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>
314
at all. This is why a separate plugin (<citerefentry>
426
315
<refentrytitle>password-prompt</refentrytitle>
427
<manvolnum>8mandos</manvolnum></citerefentry>) will prompt for
428
passwords on the system console.
316
<manvolnum>8mandos</manvolnum></citerefentry>) does that, which
317
will be run in parallel to this one by the plugin runner.
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">
625
345
<title>FILES</title>
738
446
The only remaining weak point is that someone with physical
739
447
access to the client hard drive might turn off the client
740
448
computer, read the OpenPGP keys directly from the hard drive,
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
449
and communicate with the server. The defense against this is
450
that the server is supposed to notice the client disappearing
451
and will stop giving out the encrypted data. Therefore, it is
452
important to set the timeout and checker interval values tightly
453
on the server. See <citerefentry><refentrytitle
746
454
>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>.