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 TIMESTAMP "2019-08-04">
4
<!ENTITY TIMESTAMP "2016-11-27">
5
5
<!ENTITY % common SYSTEM "common.ent">
68
65
The computers run a small client program in the initial RAM disk
69
66
environment which will communicate with a server over a network.
70
67
All network communication is encrypted using TLS. The clients
71
are identified by the server using a TLS public key; each client
68
are identified by the server using an OpenPGP key; each client
72
69
has one unique to it. The server sends the clients an encrypted
73
70
password. The encrypted password is decrypted by the clients
74
using a separate OpenPGP key, and the password is then used to
71
using the same OpenPGP key, and the password is then used to
75
72
unlock the root file system, whereupon the computers can
76
73
continue booting normally.
133
130
So, at boot time, the Mandos client will ask for its encrypted
134
data over the network, decrypt the data to get the password, use
135
the password to decrypt the root file system, and the client can
136
then continue booting.
131
data over the network, decrypt it to get the password, use it to
132
decrypt the root file, and continue booting.
139
135
Now, of course the initial RAM disk image is not on the
145
141
long, and will no longer give out the encrypted key. The timing
146
142
here is the only real weak point, and the method, frequency and
147
143
timeout of the server’s checking can be adjusted to any desired
151
147
(The encrypted keys on the Mandos server is on its normal file
203
199
No. The server only gives out the passwords to clients which
204
200
have <emphasis>in the TLS handshake</emphasis> proven that
205
they do indeed hold the private key corresponding to that
201
they do indeed hold the OpenPGP private key corresponding to
384
380
plugin requirements.
388
<refsect1 id="systemd">
389
<title>SYSTEMD</title>
391
More advanced startup systems like <citerefentry><refentrytitle
392
>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
393
already have their own plugin-like mechanisms for allowing
394
multiple agents to independently retrieve a password and deliver
395
it to the subsystem requesting a password to unlock the root
396
file system. On these systems, it would make no sense to run
397
<citerefentry><refentrytitle>plugin-runner</refentrytitle
398
><manvolnum>8mandos</manvolnum></citerefentry>, the plugins of
399
which would largely duplicate the work of (and conflict with)
400
the existing systems prompting for passwords.
403
As for <citerefentry><refentrytitle>systemd</refentrytitle
404
><manvolnum>1</manvolnum></citerefentry> in particular, it has
406
url="https://www.freedesktop.org/wiki/Software/systemd/PasswordAgents/"
407
>Password Agents</ulink> system. Mandos uses this via its
408
<citerefentry><refentrytitle>password-agent</refentrytitle
409
><manvolnum>8mandos</manvolnum></citerefentry> program, which
410
is run instead of <citerefentry><refentrytitle
411
>plugin-runner</refentrytitle><manvolnum>8mandos</manvolnum
412
></citerefentry> when <citerefentry><refentrytitle
413
>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
414
is used during system startup.
417
384
<refsect1 id="bugs">
418
385
<title>BUGS</title>
419
386
<xi:include href="bugs.xml"/>
434
401
<manvolnum>8</manvolnum></citerefentry>,
435
402
<citerefentry><refentrytitle>plugin-runner</refentrytitle>
436
403
<manvolnum>8mandos</manvolnum></citerefentry>,
437
<citerefentry><refentrytitle>password-agent</refentrytitle>
438
<manvolnum>8mandos</manvolnum></citerefentry>,
439
404
<citerefentry><refentrytitle>mandos-client</refentrytitle>
440
405
<manvolnum>8mandos</manvolnum></citerefentry>,
441
406
<citerefentry><refentrytitle>password-prompt</refentrytitle>
added
removed
intro.xml
