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diff --git a/man/crypttab.xml b/man/crypttab.xml deleted file mode 100644 index 17976f3704..0000000000 --- a/man/crypttab.xml +++ /dev/null @@ -1,427 +0,0 @@ -<?xml version="1.0"?> -<!--*-nxml-*--> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> -<!-- - This file is part of systemd. - - Copyright 2012 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. - - This is based on crypttab(5) from Fedora's initscripts package, which in - turn is based on Debian's version. - - The Red Hat version has been written by Miloslav Trmac <mitr@redhat.com>. - ---> -<refentry id="crypttab" conditional='HAVE_LIBCRYPTSETUP'> - - <refentryinfo> - <title>crypttab</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>Documentation</contrib> - <firstname>Miloslav</firstname> - <surname>Trmac</surname> - <email>mitr@redhat.com</email> - </author> - <author> - <contrib>Documentation</contrib> - <firstname>Lennart</firstname> - <surname>Poettering</surname> - <email>lennart@poettering.net</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>crypttab</refentrytitle> - <manvolnum>5</manvolnum> - </refmeta> - - <refnamediv> - <refname>crypttab</refname> - <refpurpose>Configuration for encrypted block devices</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <para><filename>/etc/crypttab</filename></para> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para>The <filename>/etc/crypttab</filename> file describes - encrypted block devices that are set up during system boot.</para> - - <para>Empty lines and lines starting with the <literal>#</literal> - character are ignored. Each of the remaining lines describes one - encrypted block device, fields on the line are delimited by white - space. The first two fields are mandatory, the remaining two are - optional.</para> - - <para>Setting up encrypted block devices using this file supports - three encryption modes: LUKS, TrueCrypt and plain. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for more information about each mode. When no mode is specified in - the options field and the block device contains a LUKS signature, - it is opened as a LUKS device; otherwise, it is assumed to be in - raw dm-crypt (plain mode) format.</para> - - <para>The first field contains the name of the resulting encrypted - block device; the device is set up within - <filename>/dev/mapper/</filename>.</para> - - <para>The second field contains a path to the underlying block - device or file, or a specification of a block device via - <literal>UUID=</literal> followed by the UUID.</para> - - <para>The third field specifies the encryption password. If the - field is not present or the password is set to - <literal>none</literal> or <literal>-</literal>, the password has - to be manually entered during system boot. Otherwise, the field is - interpreted as an absolute path to a file containing the encryption - password. For swap encryption, <filename>/dev/urandom</filename> - or the hardware device <filename>/dev/hw_random</filename> can be - used as the password file; using <filename>/dev/random</filename> - may prevent boot completion if the system does not have enough - entropy to generate a truly random encryption key.</para> - - <para>The fourth field, if present, is a comma-delimited list of - options. The following options are recognized:</para> - - <variablelist class='fstab-options'> - - <varlistentry> - <term><option>discard</option></term> - - <listitem><para>Allow discard requests to be passed through - the encrypted block device. This improves performance on SSD - storage but has security implications.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>cipher=</option></term> - - <listitem><para>Specifies the cipher to use. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for possible values and the default value of this option. A - cipher with unpredictable IV values, such as - <literal>aes-cbc-essiv:sha256</literal>, is - recommended.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>hash=</option></term> - - <listitem><para>Specifies the hash to use for password - hashing. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for possible values and the default value of this - option.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>header=</option></term> - - <listitem><para>Use a detached (separated) metadata device or - file where the LUKS header is stored. This option is only - relevant for LUKS devices. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for possible values and the default value of this - option.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>offset=</option></term> - - <listitem><para>Start offset in the backend device, in 512-byte sectors. - This option is only relevant for plain devices. - </para></listitem> - </varlistentry> - - <varlistentry> - <term><option>skip=</option></term> - - <listitem><para>How many 512-byte sectors of the encrypted data to skip - at the beginning. This is different from the <option>--offset</option> - option with respect to the sector numbers used in initialization vector - (IV) calculation. Using <option>--offset</option> will shift the IV - calculation by the same negative amount. Hence, if <option>--offset n</option> is given, - sector n will get a sector number of 0 for the IV calculation. - Using <option>--skip</option> causes sector n to also be the first - sector of the mapped device, but with its number for IV generation being n.</para> - - <para>This option is only relevant for plain devices.</para> - </listitem> - </varlistentry> - - <varlistentry> - <term><option>keyfile-offset=</option></term> - - <listitem><para>Specifies the number of bytes to skip at the - start of the key file. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for possible values and the default value of this - option.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>keyfile-size=</option></term> - - <listitem><para>Specifies the maximum number of bytes to read - from the key file. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for possible values and the default value of this option. This - option is ignored in plain encryption mode, as the key file - size is then given by the key size.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>key-slot=</option></term> - - <listitem><para>Specifies the key slot to compare the - passphrase or key against. If the key slot does not match the - given passphrase or key, but another would, the setup of the - device will fail regardless. This option implies - <option>luks</option>. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for possible values. The default is to try all key slots in - sequential order.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>luks</option></term> - - <listitem><para>Force LUKS mode. When this mode is used, the - following options are ignored since they are provided by the - LUKS header on the device: <option>cipher=</option>, - <option>hash=</option>, - <option>size=</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>noauto</option></term> - - <listitem><para>This device will not be automatically unlocked - on boot.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>nofail</option></term> - - <listitem><para>The system will not wait for the device to - show up and be unlocked at boot, and not fail the boot if it - does not show up.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>plain</option></term> - - <listitem><para>Force plain encryption mode.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>read-only</option></term><term><option>readonly</option></term> - - <listitem><para>Set up the encrypted block device in read-only - mode.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>size=</option></term> - - <listitem><para>Specifies the key size in bits. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for possible values and the default value of this - option.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>swap</option></term> - - <listitem><para>The encrypted block device will be used as a - swap device, and will be formatted accordingly after setting - up the encrypted block device, with - <citerefentry project='man-pages'><refentrytitle>mkswap</refentrytitle><manvolnum>8</manvolnum></citerefentry>. - This option implies <option>plain</option>.</para> - - <para>WARNING: Using the <option>swap</option> option will - destroy the contents of the named partition during every boot, - so make sure the underlying block device is specified - correctly.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>tcrypt</option></term> - - <listitem><para>Use TrueCrypt encryption mode. When this mode - is used, the following options are ignored since they are - provided by the TrueCrypt header on the device or do not - apply: - <option>cipher=</option>, - <option>hash=</option>, - <option>keyfile-offset=</option>, - <option>keyfile-size=</option>, - <option>size=</option>.</para> - - <para>When this mode is used, the passphrase is read from the - key file given in the third field. Only the first line of this - file is read, excluding the new line character.</para> - - <para>Note that the TrueCrypt format uses both passphrase and - key files to derive a password for the volume. Therefore, the - passphrase and all key files need to be provided. Use - <option>tcrypt-keyfile=</option> to provide the absolute path - to all key files. When using an empty passphrase in - combination with one or more key files, use - <literal>/dev/null</literal> as the password file in the third - field.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>tcrypt-hidden</option></term> - - <listitem><para>Use the hidden TrueCrypt volume. This option - implies <option>tcrypt</option>.</para> - - <para>This will map the hidden volume that is inside of the - volume provided in the second field. Please note that there is - no protection for the hidden volume if the outer volume is - mounted instead. See - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for more information on this limitation.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>tcrypt-keyfile=</option></term> - - <listitem><para>Specifies the absolute path to a key file to - use for a TrueCrypt volume. This implies - <option>tcrypt</option> and can be used more than once to - provide several key files.</para> - - <para>See the entry for <option>tcrypt</option> on the - behavior of the passphrase and key files when using TrueCrypt - encryption mode.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>tcrypt-system</option></term> - - <listitem><para>Use TrueCrypt in system encryption mode. This - option implies <option>tcrypt</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>tcrypt-veracrypt</option></term> - - <listitem><para>Check for a VeraCrypt volume. VeraCrypt is a fork of - TrueCrypt that is mostly compatible, but uses different, stronger key - derivation algorithms that cannot be detected without this flag. - Enabling this option could substantially slow down unlocking, because - VeraCrypt's key derivation takes much longer than TrueCrypt's. This - option implies <option>tcrypt</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>timeout=</option></term> - - <listitem><para>Specifies the timeout for querying for a - password. If no unit is specified, seconds is used. Supported - units are s, ms, us, min, h, d. A timeout of 0 waits - indefinitely (which is the default).</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>x-systemd.device-timeout=</option></term> - - <listitem><para>Specifies how long systemd should wait for a - device to show up before giving up on the entry. The argument - is a time in seconds or explicitly specified units of - <literal>s</literal>, - <literal>min</literal>, - <literal>h</literal>, - <literal>ms</literal>. - </para></listitem> - </varlistentry> - - <varlistentry> - <term><option>tmp</option></term> - - <listitem><para>The encrypted block device will be prepared - for using it as <filename>/tmp</filename>; it will be - formatted using - <citerefentry project='man-pages'><refentrytitle>mke2fs</refentrytitle><manvolnum>8</manvolnum></citerefentry>. - This option implies <option>plain</option>.</para> - - <para>WARNING: Using the <option>tmp</option> option will - destroy the contents of the named partition during every boot, - so make sure the underlying block device is specified - correctly.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>tries=</option></term> - - <listitem><para>Specifies the maximum number of times the user - is queried for a password. The default is 3. If set to 0, the - user is queried for a password indefinitely.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>verify</option></term> - - <listitem><para> If the encryption password is read from - console, it has to be entered twice to prevent - typos.</para></listitem> - </varlistentry> - - </variablelist> - - <para>At early boot and when the system manager configuration is - reloaded, this file is translated into native systemd units by - <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para> - </refsect1> - - <refsect1> - <title>Example</title> - <example> - <title>/etc/crypttab example</title> - <para>Set up four encrypted block devices. One using LUKS for - normal storage, another one for usage as a swap device and two - TrueCrypt volumes.</para> - - <programlisting>luks UUID=2505567a-9e27-4efe-a4d5-15ad146c258b -swap /dev/sda7 /dev/urandom swap -truecrypt /dev/sda2 /etc/container_password tcrypt -hidden /mnt/tc_hidden /dev/null tcrypt-hidden,tcrypt-keyfile=/etc/keyfile</programlisting> - </example> - </refsect1> - - <refsect1> - <title>See Also</title> - <para> - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd-cryptsetup@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>, - <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry>, - <citerefentry project='man-pages'><refentrytitle>mkswap</refentrytitle><manvolnum>8</manvolnum></citerefentry>, - <citerefentry project='man-pages'><refentrytitle>mke2fs</refentrytitle><manvolnum>8</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |