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<command>&COMMANDNAME;</command> is a client program that
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communicates with <citerefentry><refentrytitle
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>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>
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to get a password. It uses IPv6 link-local addresses to get
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network connectivity, Zeroconf to find servers, and TLS with an
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OpenPGP key to ensure authenticity and confidentiality. It
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keeps running, trying all servers on the network, until it
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receives a satisfactory reply or a TERM signal is received.
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to get a password. In slightly more detail, this client program
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brings up network interfaces, uses the interfaces’ IPv6
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link-local addresses to get network connectivity, uses Zeroconf
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to find servers on the local network, and communicates with
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servers using TLS with an OpenPGP key to ensure authenticity and
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confidentiality. This client program keeps running, trying all
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servers on the network, until it receives a satisfactory reply
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or a TERM signal. After all servers have been tried, all
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servers are periodically retried. If no servers are found it
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will wait indefinitely for new servers to appear.
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The network interfaces are selected like this: If any interfaces
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are specified using the <option>--interface</option> option,
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those interface are used. Otherwise,
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<command>&COMMANDNAME;</command> will use all interfaces that
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are not loopback interfaces, are not point-to-point interfaces,
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are capable of broadcasting and do not have the NOARP flag (see
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<citerefentry><refentrytitle>netdevice</refentrytitle>
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<manvolnum>7</manvolnum></citerefentry>). (If the
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<option>--connect</option> option is used, point-to-point
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interfaces and non-broadcast interfaces are accepted.) If any
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used interfaces are not up and running, they are first taken up
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(and later taken down again on program exit).
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Before network interfaces are selected, all <quote>network
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hooks</quote> are run; see <xref linkend="network-hooks"/>.
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This program is not meant to be run directly; it is really meant
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assumed to separate the address from the port number.
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This option is normally only useful for testing and
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Normally, Zeroconf would be used to locate Mandos servers,
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in which case this option would only be used when testing
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<term><option>--interface=
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<replaceable>NAME</replaceable></option></term>
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<term><option>--interface=<replaceable
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>NAME</replaceable><arg rep='repeat'>,<replaceable
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>NAME</replaceable></arg></option></term>
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<replaceable>NAME</replaceable></option></term>
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<replaceable>NAME</replaceable><arg rep='repeat'>,<replaceable
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>NAME</replaceable></arg></option></term>
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Network interface that will be brought up and scanned for
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Mandos servers to connect to. The default it
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<quote><literal>eth0</literal></quote>.
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If the <option>--connect</option> option is used, this
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specifies the interface to use to connect to the address
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Comma separated list of network interfaces that will be
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brought up and scanned for Mandos servers to connect to.
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The default is the empty string, which will automatically
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use all appropriate interfaces.
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If the <option>--connect</option> option is used, and
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exactly one interface name is specified (except
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<quote><literal>none</literal></quote>), this specifies
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the interface to use to connect to the address given.
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Note that since this program will normally run in the
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initial RAM disk environment, the interface must be an
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interface which exists at that stage. Thus, the interface
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can normally not be a pseudo-interface such as
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<quote>br0</quote> or <quote>tun0</quote>; such interfaces
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will not exist until much later in the boot process, and
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can not be used by this program, unless created by a
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<quote>network hook</quote> — see <xref
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linkend="network-hooks"/>.
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<replaceable>NAME</replaceable> can be the string
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<quote><literal>none</literal></quote>; this will make
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<command>&COMMANDNAME;</command> only bring up interfaces
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specified <emphasis>before</emphasis> this string. This
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is not recommended, and only meant for advanced users.
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Sets the number of bits to use for the prime number in the
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TLS Diffie-Hellman key exchange. Default is 1024.
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TLS Diffie-Hellman key exchange. The default value is
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selected automatically based on the OpenPGP key.
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<term><option>--delay=<replaceable
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>SECONDS</replaceable></option></term>
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After bringing a network interface up, the program waits
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for the interface to arrive in a <quote>running</quote>
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state before proceeding. During this time, the kernel log
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level will be lowered to reduce clutter on the system
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console, alleviating any other plugins which might be
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using the system console. This option sets the upper
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limit of seconds to wait. The default is 2.5 seconds.
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<term><option>--retry=<replaceable
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>SECONDS</replaceable></option></term>
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All Mandos servers are tried repeatedly until a password
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is received. This value specifies, in seconds, how long
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between each successive try <emphasis>for the same
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server</emphasis>. The default is 10 seconds.
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<term><option>--network-hook-dir=<replaceable
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>DIR</replaceable></option></term>
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Network hook directory. The default directory is
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<quote><filename class="directory"
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>/lib/mandos/network-hooks.d</filename></quote>.
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server could be found and the password received from it could be
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successfully decrypted and output on standard output. The
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program will exit with a non-zero exit status only if a critical
332
error occurs. Otherwise, it will forever connect to new
333
<application>Mandos</application> servers as they appear, trying
334
to get a decryptable password and print it.
441
error occurs. Otherwise, it will forever connect to any
442
discovered <application>Mandos</application> servers, trying to
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get a decryptable password and print it.
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<refsect1 id="environment">
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<title>ENVIRONMENT</title>
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<term><envar>MANDOSPLUGINHELPERDIR</envar></term>
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This environment variable will be assumed to contain the
455
directory containing any helper executables. The use and
456
nature of these helper executables, if any, is
457
purposefully not documented.
341
This program does not use any environment variables, not even
342
the ones provided by <citerefentry><refentrytitle
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This program does not use any other environment variables, not
464
even the ones provided by <citerefentry><refentrytitle
343
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>cryptsetup</refentrytitle><manvolnum>8</manvolnum>
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<refsect1 id="network-hooks">
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<title>NETWORK HOOKS</title>
473
If a network interface like a bridge or tunnel is required to
474
find a Mandos server, this requires the interface to be up and
475
running before <command>&COMMANDNAME;</command> starts looking
476
for Mandos servers. This can be accomplished by creating a
477
<quote>network hook</quote> program, and placing it in a special
481
Before the network is used (and again before program exit), any
482
runnable programs found in the network hook directory are run
483
with the argument <quote><literal>start</literal></quote> or
484
<quote><literal>stop</literal></quote>. This should bring up or
485
down, respectively, any network interface which
486
<command>&COMMANDNAME;</command> should use.
488
<refsect2 id="hook-requirements">
489
<title>REQUIREMENTS</title>
491
A network hook must be an executable file, and its name must
492
consist entirely of upper and lower case letters, digits,
493
underscores, periods, and hyphens.
496
A network hook will receive one argument, which can be one of
501
<term><literal>start</literal></term>
504
This should make the network hook create (if necessary)
505
and bring up a network interface.
510
<term><literal>stop</literal></term>
513
This should make the network hook take down a network
514
interface, and delete it if it did not exist previously.
519
<term><literal>files</literal></term>
522
This should make the network hook print, <emphasis>one
523
file per line</emphasis>, all the files needed for it to
524
run. (These files will be copied into the initial RAM
525
filesystem.) Typical use is for a network hook which is
526
a shell script to print its needed binaries.
529
It is not necessary to print any non-executable files
530
already in the network hook directory, these will be
531
copied implicitly if they otherwise satisfy the name
537
<term><literal>modules</literal></term>
540
This should make the network hook print, <emphasis>on
541
separate lines</emphasis>, all the kernel modules needed
542
for it to run. (These modules will be copied into the
543
initial RAM filesystem.) For instance, a tunnel
545
<quote><literal>tun</literal></quote> module.
551
The network hook will be provided with a number of environment
556
<term><envar>MANDOSNETHOOKDIR</envar></term>
559
The network hook directory, specified to
560
<command>&COMMANDNAME;</command> by the
561
<option>--network-hook-dir</option> option. Note: this
562
should <emphasis>always</emphasis> be used by the
563
network hook to refer to itself or any files in the hook
564
directory it may require.
569
<term><envar>DEVICE</envar></term>
572
The network interfaces, as specified to
573
<command>&COMMANDNAME;</command> by the
574
<option>--interface</option> option, combined to one
575
string and separated by commas. If this is set, and
576
does not contain the interface a hook will bring up,
577
there is no reason for a hook to continue.
582
<term><envar>MODE</envar></term>
585
This will be the same as the first argument;
586
i.e. <quote><literal>start</literal></quote>,
587
<quote><literal>stop</literal></quote>,
588
<quote><literal>files</literal></quote>, or
589
<quote><literal>modules</literal></quote>.
594
<term><envar>VERBOSITY</envar></term>
597
This will be the <quote><literal>1</literal></quote> if
598
the <option>--debug</option> option is passed to
599
<command>&COMMANDNAME;</command>, otherwise
600
<quote><literal>0</literal></quote>.
605
<term><envar>DELAY</envar></term>
608
This will be the same as the <option>--delay</option>
609
option passed to <command>&COMMANDNAME;</command>. Is
610
only set if <envar>MODE</envar> is
611
<quote><literal>start</literal></quote> or
612
<quote><literal>stop</literal></quote>.
617
<term><envar>CONNECT</envar></term>
620
This will be the same as the <option>--connect</option>
621
option passed to <command>&COMMANDNAME;</command>. Is
622
only set if <option>--connect</option> is passed and
623
<envar>MODE</envar> is
624
<quote><literal>start</literal></quote> or
625
<quote><literal>stop</literal></quote>.
631
A hook may not read from standard input, and should be
632
restrictive in printing to standard output or standard error
633
unless <varname>VERBOSITY</varname> is
634
<quote><literal>1</literal></quote>.
348
639
<refsect1 id="files">
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<title>FILES</title>