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diff --git a/man/systemd-dissect.xml b/man/systemd-dissect.xml new file mode 100644 index 0000000..b04dadc --- /dev/null +++ b/man/systemd-dissect.xml @@ -0,0 +1,308 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> +<!-- SPDX-License-Identifier: LGPL-2.1-or-later --> + +<refentry id="systemd-dissect" conditional='HAVE_BLKID' + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>systemd-dissect</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>systemd-dissect</refentrytitle> + <manvolnum>1</manvolnum> + </refmeta> + + <refnamediv> + <refname>systemd-dissect</refname> + <refpurpose>Dissect Discoverable Disk Images (DDIs)</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <cmdsynopsis> + <command>systemd-dissect <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="plain"><replaceable>IMAGE</replaceable></arg></command> + </cmdsynopsis> + <cmdsynopsis> + <command>systemd-dissect <arg choice="opt" rep="repeat">OPTIONS</arg> <option>--mount</option> <arg choice="plain"><replaceable>IMAGE</replaceable></arg> <arg choice="plain"><replaceable>PATH</replaceable></arg></command> + </cmdsynopsis> + <cmdsynopsis> + <command>systemd-dissect <arg choice="opt" rep="repeat">OPTIONS</arg> <option>--umount</option> <arg choice="plain"><replaceable>PATH</replaceable></arg></command> + </cmdsynopsis> + <cmdsynopsis> + <command>systemd-dissect <arg choice="opt" rep="repeat">OPTIONS</arg> <option>--copy-from</option> <arg choice="plain"><replaceable>IMAGE</replaceable></arg> <arg choice="plain"><replaceable>PATH</replaceable></arg> <arg choice="opt"><replaceable>TARGET</replaceable></arg></command> + </cmdsynopsis> + <cmdsynopsis> + <command>systemd-dissect <arg choice="opt" rep="repeat">OPTIONS</arg> <option>--copy-to</option> <arg choice="plain"><replaceable>IMAGE</replaceable></arg> <arg choice="opt"><replaceable>SOURCE</replaceable></arg> <arg choice="plain"><replaceable>PATH</replaceable></arg></command> + </cmdsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><command>systemd-dissect</command> is a tool for introspecting and interacting with file system OS + disk images, specifically Discoverable Disk Images (DDIs). It supports five different operations:</para> + + <orderedlist> + <listitem><para>Show general OS image information, including the image's + <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry> data, + machine ID, partition information and more.</para></listitem> + + <listitem><para>Mount an OS image to a local directory. In this mode it will dissect the OS image and + mount the included partitions according to their designation onto a directory and possibly + sub-directories.</para></listitem> + + <listitem><para>Unmount an OS image from a local directory. In this mode it will recursively unmount + the mounted partitions and remove the underlying loop device, including all the partition sub-devices. + </para></listitem> + + <listitem><para>Copy files and directories in and out of an OS image.</para></listitem> + </orderedlist> + + <para>The tool may operate on three types of OS images:</para> + + <orderedlist> + <listitem><para>OS disk images containing a GPT partition table envelope, with partitions marked + according to the <ulink url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable Partitions + Specification</ulink>.</para></listitem> + + <listitem><para>OS disk images containing just a plain file-system without an enveloping partition + table. (This file system is assumed to be the root file system of the OS.)</para></listitem> + + <listitem><para>OS disk images containing a GPT or MBR partition table, with a single + partition only. (This partition is assumed to contain the root file system of the OS.)</para></listitem> + </orderedlist> + + <para>OS images may use any kind of Linux-supported file systems. In addition they may make use of LUKS + disk encryption, and contain Verity integrity information. Note that qualifying OS images may be booted + with <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s + <option>--image=</option> switch, and be used as root file system for system service using the + <varname>RootImage=</varname> unit file setting, see + <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para> + + <para>Note that the partition table shown when invoked without command switch (as listed below) does not + necessarily show all partitions included in the image, but just the partitions that are understood and + considered part of an OS disk image. Specifically, partitions of unknown types are ignored, as well as + duplicate partitions (i.e. more than one per partition type), as are root and <filename>/usr/</filename> + partitions of architectures not compatible with the local system. In other words: this tool will display + what it operates with when mounting the image. To display the complete list of partitions use a tool such + as <citerefentry + project='man-pages'><refentrytitle>fdisk</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para> + </refsect1> + + <refsect1> + <title>Commands</title> + + <para>If neither of the command switches listed below are passed the specified disk image is opened and + general information about the image and the contained partitions and their use is shown.</para> + + <variablelist> + <varlistentry> + <term><option>--mount</option></term> + <term><option>-m</option></term> + + <listitem><para>Mount the specified OS image to the specified directory. This will dissect the image, + determine the OS root file system — as well as possibly other partitions — and mount them to the + specified directory. If the OS image contains multiple partitions marked with the <ulink + url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable Partitions Specification</ulink> + multiple nested mounts are established. This command expects two arguments: a path to an image file + and a path to a directory where to mount the image.</para> + + <para>To unmount an OS image mounted like this use the <option>--umount</option> operation.</para> + + <para>When the OS image contains LUKS encrypted or Verity integrity protected file systems + appropriate volumes are automatically set up and marked for automatic disassembly when the image is + unmounted.</para> + + <para>The OS image may either be specified as path to an OS image stored in a regular file or may + refer to block device node (in the latter case the block device must be the "whole" device, i.e. not + a partition device). (The other supported commands described here support this, too.)</para> + + <para>All mounted file systems are checked with the appropriate <citerefentry + project='man-pages'><refentrytitle>fsck</refentrytitle><manvolnum>8</manvolnum></citerefentry> + implementation in automatic fixing mode, unless explicitly turned off (<option>--fsck=no</option>) or + read-only operation is requested (<option>--read-only</option>).</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>-M</option></term> + + <listitem><para>This is a shortcut for <option>--mount --mkdir</option>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--umount</option></term> + <term><option>-u</option></term> + + <listitem><para>Unmount an OS image from the specified directory. This command expects one argument: + a directory where an OS image was mounted.</para> + + <para>All mounted partitions will be recursively unmounted, and the underlying loop device will be + removed, along with all its partition sub-devices.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>-U</option></term> + + <listitem><para>This is a shortcut for <option>--umount --rmdir</option>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--copy-from</option></term> + <term><option>-x</option></term> + + <listitem><para>Copies a file or directory from the specified OS image into the specified location on + the host file system. Expects three arguments: a path to an image file, a source path (relative to + the image's root directory) and a destination path (relative to the current working directory, or an + absolute path, both outside of the image). If the destination path is omitted or specified as dash + (<literal>-</literal>), the specified file is written to standard output. If the source path in the + image file system refers to a regular file it is copied to the destination path. In this case access + mode, extended attributes and timestamps are copied as well, but file ownership is not. If the source + path in the image refers to a directory, it is copied to the destination path, recursively with all + containing files and directories. In this case the file ownership is copied too.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--copy-to</option></term> + <term><option>-a</option></term> + + <listitem><para>Copies a file or directory from the specified location in the host file system into + the specified OS image. Expects three arguments: a path to an image file, a source path (relative to + the current working directory, or an absolute path, both outside of the image) and a destination path + (relative to the image's root directory). If the source path is omitted or specified as dash + (<literal>-</literal>), the data to write is read from standard input. If the source path in the host + file system refers to a regular file, it is copied to the destination path. In this case access mode, + extended attributes and timestamps are copied as well, but file ownership is not. If the source path + in the host file system refers to a directory it is copied to the destination path, recursively with + all containing files and directories. In this case the file ownership is copied + too.</para> + + <para>As with <option>--mount</option> file system checks are implicitly run before the copy + operation begins.</para></listitem> + </varlistentry> + + <xi:include href="standard-options.xml" xpointer="help" /> + <xi:include href="standard-options.xml" xpointer="version" /> + </variablelist> + + </refsect1> + + <refsect1> + <title>Options</title> + + <para>The following options are understood:</para> + + <variablelist> + <varlistentry> + <term><option>--read-only</option></term> + <term><option>-r</option></term> + + <listitem><para>Operate in read-only mode. By default <option>--mount</option> will establish + writable mount points. If this option is specified they are established in read-only mode + instead.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--fsck=no</option></term> + + <listitem><para>Turn off automatic file system checking. By default when an image is accessed for + writing (by <option>--mount</option> or <option>--copy-to</option>) the file systems contained in the + OS image are automatically checked using the appropriate <citerefentry + project='man-pages'><refentrytitle>fsck</refentrytitle><manvolnum>8</manvolnum></citerefentry> + command, in automatic fixing mode. This behavior may be switched off using + <option>--fsck=no</option>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--growfs=no</option></term> + + <listitem><para>Turn off automatic growing of accessed file systems to their partition size, if + marked for that in the GPT partition table. By default when an image is accessed for writing (by + <option>--mount</option> or <option>--copy-to</option>) the file systems contained in the OS image + are automatically grown to their partition sizes, if bit 59 in the GPT partition flags is set for + partition types that are defined by the <ulink + url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable Partitions Specification</ulink>. This + behavior may be switched off using <option>--growfs=no</option>. File systems are grown automatically + on access if all of the following conditions are met:</para> + <orderedlist> + <listitem><para>The file system is mounted writable</para></listitem> + <listitem><para>The file system currently is smaller than the partition it is contained in (and thus can be grown)</para></listitem> + <listitem><para>The image contains a GPT partition table</para></listitem> + <listitem><para>The file system is stored on a partition defined by the Discoverable Partitions Specification</para></listitem> + <listitem><para>Bit 59 of the GPT partition flags for this partition is set, as per specification</para></listitem> + <listitem><para>The <option>--growfs=no</option> option is not passed.</para></listitem> + </orderedlist> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>--mkdir</option></term> + + <listitem><para>If combined with <option>--mount</option> the directory to mount the OS image to is + created if it is missing. Note that the directory is not automatically removed when the disk image is + unmounted again.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--rmdir</option></term> + + <listitem><para>If combined with <option>--umount</option> the specified directory where the OS image + is mounted is removed after unmounting the OS image.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--discard=</option></term> + + <listitem><para>Takes one of <literal>disabled</literal>, <literal>loop</literal>, + <literal>all</literal>, <literal>crypto</literal>. If <literal>disabled</literal> the image is + accessed with empty block discarding turned off. If <literal>loop</literal> discarding is enabled if + operating on a regular file. If <literal>crypt</literal> discarding is enabled even on encrypted file + systems. If <literal>all</literal> discarding is unconditionally enabled.</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>--root-hash=</option></term> + <term><option>--root-hash-sig=</option></term> + <term><option>--verity-data=</option></term> + + <listitem><para>Configure various aspects of Verity data integrity for the OS image. Option + <option>--root-hash=</option> specifies a hex-encoded top-level Verity hash to use for setting up the + Verity integrity protection. Option <option>--root-hash-sig=</option> specifies the path to a file + containing a PKCS#7 signature for the hash. This signature is passed to the kernel during activation, + which will match it against signature keys available in the kernel keyring. Option + <option>--verity-data=</option> specifies a path to a file with the Verity data to use for the OS + image, in case it is stored in a detached file. It is recommended to embed the Verity data directly + in the image, using the Verity mechanisms in the <ulink + url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable Partitions Specification</ulink>. + </para></listitem> + </varlistentry> + + <xi:include href="standard-options.xml" xpointer="no-pager" /> + <xi:include href="standard-options.xml" xpointer="no-legend" /> + <xi:include href="standard-options.xml" xpointer="json" /> + </variablelist> + + </refsect1> + + <refsect1> + <title>Exit status</title> + + <para>On success, 0 is returned, a non-zero failure code + otherwise.</para> + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <ulink url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable Partitions Specification</ulink>, + <citerefentry project='man-pages'><refentrytitle>umount</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>fdisk</refentrytitle><manvolnum>8</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |