mirror of
https://github.com/systemd/systemd.git
synced 2024-12-25 01:34:28 +03:00
6efdd7fec5
Currently we have a 100ms delay which allows for people to enter/show the boot menu even when timeout is set to zero. In a handful of cases, that may not be needed - both in terms of access policy, as well as latency. For example: the option to provide the boot menu may be hidden behind an "expert only" UX in the OS, to avoid end users from accidentally entering it. In addition, the current 100ms input polling may cause unexpected additional delays in the boot. Some example numbers from my SteamDeck: - boot counting/rename/flush doubles 300us -> 600us - seed/hash setup doubles 900us -> 1800us - kernel/image load gets ~40% slower 107ms -> 167ms It's not entirely clear why the UEFI calls gets slower, nevertheless the information in itself proves useful. This commit introduces a new option "menu-disabled", which omits the 100ms delay. The option is documented throughout the manual pages as well as the Boot Loader Specification. v2: - use STR_IN_SET v3: - drop erroneous whitespace v4: - add a new LoaderFeature bit, - don't change ABI keep TIMEOUT_* tokens the same - move new token in the 64bit range, update API and storage for it - change inc/dec behaviour to TIMEOUT_MIN : TIMEOUT_MENU_FORCE - user cannot opt-in from sd-boot itself, add assert_not_reached() v5: - s/Menu disablement control/Menu can be disabled/ - rewrap comments to 109 - use SYNTHETIC_ERRNO(EOPNOTSUPP) Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
431 lines
19 KiB
XML
431 lines
19 KiB
XML
<?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="loader.conf" conditional='ENABLE_BOOTLOADER'
|
|
xmlns:xi="http://www.w3.org/2001/XInclude">
|
|
<refentryinfo>
|
|
<title>loader.conf</title>
|
|
<productname>systemd</productname>
|
|
</refentryinfo>
|
|
|
|
<refmeta>
|
|
<refentrytitle>loader.conf</refentrytitle>
|
|
<manvolnum>5</manvolnum>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>loader.conf</refname>
|
|
<refpurpose>Configuration file for systemd-boot</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<para><filename><replaceable>ESP</replaceable>/loader/loader.conf</filename>,
|
|
<filename><replaceable>ESP</replaceable>/loader/entries/*.conf</filename>
|
|
<filename><replaceable>XBOOTLDR</replaceable>/loader/entries/*.conf</filename>
|
|
</para>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
<citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry> will
|
|
read <filename><replaceable>ESP</replaceable>/loader/loader.conf</filename>, and any files with the
|
|
<literal>.conf</literal> extension under
|
|
<filename><replaceable>ESP</replaceable>/loader/entries/</filename> on the EFI system partition (ESP),
|
|
and <filename><replaceable>XBOOTLDR</replaceable>/loader/entries/</filename> on the extended boot loader
|
|
partition (XBOOTLDR) as defined by <ulink url="https://uapi-group.org/specifications/specs/boot_loader_specification">Boot Loader
|
|
Specification</ulink>.
|
|
</para>
|
|
|
|
<para>Each of these configuration files must consist of series of newline (i.e. ASCII code 10) separated
|
|
lines, each consisting of an option name, followed by whitespace, and the option
|
|
value. <literal>#</literal> may be used to start a comment line. Empty and comment lines are ignored. The
|
|
files use UTF-8 encoding.</para>
|
|
|
|
<para>Boolean arguments may be written as
|
|
<literal>yes</literal>/<literal>y</literal>/<literal>true</literal>/<literal>t</literal>/<literal>on</literal>/<literal>1</literal> or
|
|
<literal>no</literal>/<literal>n</literal>/<literal>false</literal>/<literal>f</literal>/<literal>off</literal>/<literal>0</literal>.
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Options</title>
|
|
|
|
<para>The configuration options supported by
|
|
<filename><replaceable>ESP</replaceable>/loader/entries/*.conf</filename> and
|
|
<filename><replaceable>XBOOTLDR</replaceable>/loader/entries/*.conf</filename> files are defined as part
|
|
of the <ulink url="https://uapi-group.org/specifications/specs/boot_loader_specification">Boot Loader
|
|
Specification</ulink>.</para>
|
|
|
|
<para>The following configuration are supported by the <filename>loader.conf</filename> configuration
|
|
file:</para>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term>default</term>
|
|
|
|
<listitem><para>A glob pattern to select the default entry. The default entry
|
|
may be changed in the boot menu itself, in which case the name of the
|
|
selected entry will be stored as an EFI variable, overriding this option.
|
|
</para>
|
|
|
|
<para>If set to <literal>@saved</literal> the chosen entry will be saved as an EFI variable
|
|
on every boot and automatically selected the next time the boot loader starts.</para>
|
|
|
|
<table>
|
|
<title>Automatically detected entries will use the following names:</title>
|
|
|
|
<tgroup cols='2'>
|
|
<colspec colname='name' />
|
|
<colspec colname='expl' />
|
|
<thead>
|
|
<row>
|
|
<entry>Name</entry>
|
|
<entry>Description</entry>
|
|
</row>
|
|
</thead>
|
|
<tbody>
|
|
<row>
|
|
<entry>auto-efi-default</entry>
|
|
<entry>EFI Default Loader</entry>
|
|
</row>
|
|
<row>
|
|
<entry>auto-efi-shell</entry>
|
|
<entry>EFI Shell</entry>
|
|
</row>
|
|
<row>
|
|
<entry>auto-osx</entry>
|
|
<entry>macOS</entry>
|
|
</row>
|
|
<row>
|
|
<entry>auto-poweroff</entry>
|
|
<entry>Power Off The System</entry>
|
|
</row>
|
|
<row>
|
|
<entry>auto-reboot</entry>
|
|
<entry>Reboot The System</entry>
|
|
</row>
|
|
<row>
|
|
<entry>auto-reboot-to-firmware-setup</entry>
|
|
<entry>Reboot Into Firmware Interface</entry>
|
|
</row>
|
|
<row>
|
|
<entry>auto-windows</entry>
|
|
<entry>Windows Boot Manager</entry>
|
|
</row>
|
|
</tbody>
|
|
</tgroup>
|
|
</table>
|
|
|
|
<para>Supported glob wildcard patterns are <literal>?</literal>, <literal>*</literal>, and
|
|
<literal>[…]</literal> (including ranges). Note that these patterns use the same syntax as
|
|
<citerefentry project='man-pages'><refentrytitle>glob</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
|
but do not support all features. In particular, set negation and named character classes are not
|
|
supported. The matching is done case-insensitively on the entry ID (as shown by <command>bootctl
|
|
list</command>).</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>timeout</term>
|
|
|
|
<listitem><para>How long the boot menu should be shown before the default
|
|
entry is booted, in seconds. This may be changed in the boot menu itself and
|
|
will be stored as an EFI variable in that case, overriding this option.
|
|
</para>
|
|
|
|
<para>If set to <literal>menu-disabled</literal> or <literal>menu-hidden</literal> or <literal>0</literal>
|
|
(the default), no menu is shown and the default entry will be booted immediately. Unless
|
|
<literal>menu-disabled</literal> is used, the menu can be shown
|
|
by pressing and holding a key before systemd-boot is launched. Setting this to
|
|
<literal>menu-force</literal> disables the timeout while always showing the menu.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>console-mode</term>
|
|
|
|
<listitem><para>This option configures the resolution of the console. This may be changed in
|
|
the boot menu itself and will be stored as an EFI variable in that case, overriding this
|
|
option.</para>
|
|
|
|
<para>Takes a number or one of the special values listed below. The following
|
|
values may be used:</para>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term>0</term>
|
|
<listitem>
|
|
<para>Standard UEFI 80x25 mode</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>1</term>
|
|
<listitem>
|
|
<para>80x50 mode, not supported by all devices</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>2</term>
|
|
<listitem>
|
|
<para>the first non-standard mode provided by the device
|
|
firmware, if any</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>auto</term>
|
|
<listitem>
|
|
<para>Pick a suitable mode automatically using heuristics</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>max</term>
|
|
<listitem>
|
|
<para>Pick the highest-numbered available mode</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>keep</term>
|
|
<listitem>
|
|
<para>Keep the mode selected by firmware (the default)</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/>
|
|
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>editor</term>
|
|
|
|
<listitem><para>Takes a boolean argument. Enable (the default) or disable the
|
|
editor. The editor should be disabled if the machine can be accessed by
|
|
unauthorized persons.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>auto-entries</term>
|
|
|
|
<listitem><para>Takes a boolean argument. Enable (the default) or disable
|
|
entries for other boot entries found on the boot partition. In particular,
|
|
this may be useful when loader entries are created to show replacement
|
|
descriptions for those entries.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>auto-firmware</term>
|
|
|
|
<listitem><para>A boolean controlling the presence of the <literal>Reboot Into Firmware
|
|
Interface</literal> entry (enabled by default). If this is disabled, the firmware interface may still
|
|
be reached by using the <keycap>f</keycap> key.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v239"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>beep</term>
|
|
|
|
<listitem><para>Takes a boolean argument. If timeout enabled beep every second, otherwise beep n times when n-th entry in boot menu is selected (default disabled).
|
|
Currently, only x86 is supported, where it uses the PC speaker.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v251"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>secure-boot-enroll</term>
|
|
|
|
<listitem><para>Danger: this feature might soft-brick your device if used improperly.</para>
|
|
|
|
<para>Controls enrollment of secure boot keys found on the ESP if the system is in setup mode:
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><option>off</option></term>
|
|
<listitem><para>No action is taken.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v253"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>manual</option></term>
|
|
<listitem><para>Boot entries for found secure boot keys are created that allow manual
|
|
enrollment.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v253"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>if-safe</option></term>
|
|
<listitem><para>Same behavior as <option>manual</option>, but will try to automatically
|
|
enroll the key <literal>auto</literal> if it is considered to be safe. Currently, this is only
|
|
the case if the system is running inside a virtual machine.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v253"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>force</option></term>
|
|
<listitem><para>Always enroll the <literal>auto</literal> key if found. Note that a warning
|
|
message with a timeout will still be shown if this operation is unknown to be safe.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v253"/></listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</para>
|
|
|
|
<para>The different sets of variables can be set up under
|
|
<filename>/loader/keys/<replaceable>NAME</replaceable></filename> where
|
|
<replaceable>NAME</replaceable> is the name that is going to be used as the name of the entry. This
|
|
allows one to ship multiple sets of Secure Boot variables and choose which one to enroll at runtime.
|
|
</para>
|
|
|
|
<para>Supported Secure Boot variables are one database for authorized images, one for the key
|
|
exchange key (KEK) and one for the platform key (PK). For more information, refer to the
|
|
<ulink url="https://uefi.org/specifications">UEFI specification</ulink>, under Secure Boot and Driver
|
|
Signing. Another resource that describe the interplay of the different variables is the
|
|
<ulink url="https://edk2-docs.gitbook.io/understanding-the-uefi-secure-boot-chain/secure_boot_chain_in_uefi/uefi_secure_boot">
|
|
EDK2 documentation</ulink>.</para>
|
|
|
|
<para>A complete set of UEFI variable includes <filename>db.auth</filename>, <filename>KEK.auth</filename>
|
|
and <filename>PK.auth</filename>. Note that these files need to be authenticated UEFI variables. See
|
|
below for an example of how to generate them from regular X.509 keys.</para>
|
|
|
|
<programlisting>uuid=$(systemd-id128 new --uuid)
|
|
for key in PK KEK db; do
|
|
openssl req -new -x509 -subj "/CN=${key}/" -keyout "${key}.key" -out "${key}.pem"
|
|
openssl x509 -outform DER -in "${key}.pem" -out "${key}.der"
|
|
sbsiglist --owner "${uuid}" --type x509 --output "${key}.esl" "${key}.der"
|
|
done
|
|
|
|
# See also: <ulink url="https://learn.microsoft.com/en-us/windows-hardware/manufacture/desktop/windows-secure-boot-key-creation-and-management-guidance">Windows Secure Boot Key Creation and Management Guidance</ulink>
|
|
curl --location \
|
|
"https://go.microsoft.com/fwlink/p/?linkid=321192" -o ms-db-2011.der \
|
|
"https://go.microsoft.com/fwlink/p/?linkid=321185" -o ms-kek-2011.der \
|
|
"https://go.microsoft.com/fwlink/p/?linkid=321194" -o ms-uefi-db-2011.der \
|
|
"https://go.microsoft.com/fwlink/p/?linkid=2239776" -o ms-db-2023.der \
|
|
"https://go.microsoft.com/fwlink/p/?linkid=2239775" -o ms-kek-2023.der \
|
|
"https://go.microsoft.com/fwlink/p/?linkid=2239872" -o ms-uefi-db-2023.der
|
|
sha1sum -c <<END
|
|
580a6f4cc4e4b669b9ebdc1b2b3e087b80d0678d ms-db-2011.der
|
|
31590bfd89c9d74ed087dfac66334b3931254b30 ms-kek-2011.der
|
|
46def63b5ce61cf8ba0de2e6639c1019d0ed14f3 ms-uefi-db-2011.der
|
|
45a0fa32604773c82433c3b7d59e7466b3ac0c67 ms-db-2023.der
|
|
459ab6fb5e284d272d5e3e6abc8ed663829d632b ms-kek-2023.der
|
|
b5eeb4a6706048073f0ed296e7f580a790b59eaa ms-uefi-db-2023.der
|
|
END
|
|
for key in ms-*.der; do
|
|
sbsiglist --owner 77fa9abd-0359-4d32-bd60-28f4e78f784b --type x509 --output "${key%der}esl" "${key}"
|
|
done
|
|
|
|
# Optionally add Microsoft Windows certificates (needed to boot into Windows).
|
|
cat ms-db-*.esl >>db.esl
|
|
|
|
# Optionally add Microsoft UEFI certificates for firmware drivers / option ROMs and third-party
|
|
# boot loaders (including shim). This is highly recommended on real hardware as not including this
|
|
# may soft-brick your device (see next paragraph).
|
|
cat ms-uefi-*.esl >>db.esl
|
|
|
|
# Optionally add Microsoft KEK certificates. Recommended if either of the Microsoft keys is used as
|
|
# the official UEFI revocation database is signed with this key. The revocation database can be
|
|
# updated with <citerefentry project='man-pages'><refentrytitle>fwupdmgr</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
|
|
cat ms-kek-*.esl >>KEK.esl
|
|
|
|
attr=NON_VOLATILE,RUNTIME_ACCESS,BOOTSERVICE_ACCESS,TIME_BASED_AUTHENTICATED_WRITE_ACCESS
|
|
sbvarsign --attr "${attr}" --key PK.key --cert PK.pem --output PK.auth PK PK.esl
|
|
sbvarsign --attr "${attr}" --key PK.key --cert PK.pem --output KEK.auth KEK KEK.esl
|
|
sbvarsign --attr "${attr}" --key KEK.key --cert KEK.pem --output db.auth db db.esl
|
|
</programlisting>
|
|
|
|
<para>This feature is considered dangerous because even if all the required files are signed with the
|
|
keys being loaded, some files necessary for the system to function properly still won't be. This
|
|
is especially the case with Option ROMs (e.g. for storage controllers or graphics cards). See
|
|
<ulink url="https://github.com/Foxboron/sbctl/wiki/FAQ#option-rom">Secure Boot and Option ROMs</ulink>
|
|
for more details.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v252"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>reboot-for-bitlocker</term>
|
|
|
|
<listitem><para>Caveat: This feature is experimental, and is likely to be changed (or removed in its
|
|
current form) in a future version of systemd.</para>
|
|
|
|
<para>Work around BitLocker requiring a recovery key when the boot loader was
|
|
updated (disabled by default).</para>
|
|
|
|
<para>Try to detect BitLocker encrypted drives along with an active TPM. If both are found and
|
|
Windows Boot Manager is selected in the boot menu, set the <literal>BootNext</literal> EFI variable
|
|
and restart the system. The firmware will then start Windows Boot Manager directly, leaving the TPM
|
|
PCRs in expected states so that Windows can unseal the encryption key. This allows
|
|
<citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry> to
|
|
be updated without having to provide the recovery key for BitLocker drive unlocking.</para>
|
|
|
|
<para>Note that the PCRs that Windows uses can be configured with the
|
|
<literal>Configure TPM platform validation profile for native UEFI firmware configurations</literal>
|
|
group policy under <literal>Computer Configuration\Administrative Templates\Windows Components\BitLocker Drive Encryption</literal>.
|
|
When Secure Boot is enabled, changing this to PCRs <literal>0,2,7,11</literal> should be safe.
|
|
The TPM key protector needs to be removed and then added back for the PCRs on an already
|
|
encrypted drive to change. If PCR 4 is not measured, this setting can be disabled to speed
|
|
up booting into Windows.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v251"/></listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Example</title>
|
|
|
|
<programlisting># /boot/efi/loader/loader.conf
|
|
timeout 0
|
|
default 01234567890abcdef1234567890abdf0-*
|
|
editor no
|
|
</programlisting>
|
|
|
|
<para>The menu will not be shown by default (the menu can still be shown by
|
|
pressing and holding a key during boot). One of the entries with files with a
|
|
name starting with <literal>01234567890abcdef1234567890abdf0-</literal> will be
|
|
selected by default. If more than one entry matches, the one with the highest
|
|
priority will be selected (generally the one with the highest version number).
|
|
The editor will be disabled, so it is not possible to alter the kernel command
|
|
line.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>See Also</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>bootctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
</refentry>
|