systemd/man/systemd.pcrlock.xml

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<refentry id="systemd.pcrlock"
          xmlns:xi="http://www.w3.org/2001/XInclude">

  <refentryinfo>
    <title>systemd.pcrlock</title>
    <productname>systemd</productname>
  </refentryinfo>

  <refmeta>
    <refentrytitle>systemd.pcrlock</refentrytitle>
    <manvolnum>5</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd.pcrlock</refname>
    <refname>systemd.pcrlock.d</refname>
    <refpurpose>PCR measurement prediction files</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <para><simplelist>
      <member><filename>/etc/pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/etc/pcrlock.d/*.pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/run/pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/run/pcrlock.d/*.pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/var/lib/pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/var/lib/pcrlock.d/*.pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/usr/local/pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/usr/local/pcrlock.d/*.pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/usr/lib/pcrlock.d/*.pcrlock</filename></member>
      <member><filename>/usr/lib/pcrlock.d/*.pcrlock.d/*.pcrlock</filename></member>
    </simplelist></para>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><filename>*.pcrlock</filename> files define expected TPM2 PCR measurements of components involved
    in the boot
    process. <citerefentry><refentrytitle>systemd-pcrlock</refentrytitle><manvolnum>1</manvolnum></citerefentry>
    uses such pcrlock files to analyze and predict TPM2 PCR measurements. The pcrlock files are JSON arrays
    that follow a subset of the <ulink
    url="https://trustedcomputinggroup.org/resource/canonical-event-log-format/">TCG Canonical Event Log Format
    (CEL-JSON)</ulink> specification. Specifically the <literal>recnum</literal>, <literal>content</literal>,
    and <literal>content_type</literal> record fields are not used and ignored if present. Each pcrlock file
    defines one set of expected, ordered PCR measurements of a specific component of the boot.</para>

    <para>*.pcrlock files may be placed in various <filename>.d/</filename> drop-in directories (see above
    for a full list). All matching files discovered in these directories are sorted alphabetically by their
    file name (without taking the actual directory they were found in into account): pcrlock files with
    alphabetically earlier names are expected to cover measurements done before those with alphabetically
    later names. In order to make positioning pcrlock files in the boot process convenient the files are
    expected (by convention, this is not enforced) to be named
    <literal><replaceable>NNN</replaceable>-<replaceable>component</replaceable>.pcrlock</literal> (where
    <replaceable>NNN</replaceable> is a three-digit decimal number), for example
    <filename>750-enter-initrd.pcrlock</filename>.</para>

    <para>For various components of the boot process more than one alternative pcrlock file shall be
    supported (i.e. "variants"). For example to cover multiple kernels installed in parallel in the access
    policy, or multiple versions of the boot loader. This can be done by placing
    <filename>*.pcrlock.d/*.pcrlock</filename> in the drop-in dirs, i.e. a common directory for a specific
    component, that contains one or more pcrlock files each covering one <emphasis>variant</emphasis> of the
    component. Example: <filename>650-kernel.pcrlock.d/6.5.5-200.fc38.x86_64.pcrlock</filename> and
    <filename>650-kernel.pcrlock.d/6.5.7-100.fc38.x86_64.pcrlock</filename></para>

    <para>Use <command>systemd-pcrlock list-components</command> to list all pcrlock files currently
    installed.</para>

    <para>Use the various <command>lock-*</command> commands of <command>systemd-pcrlock</command> to
    automatically generate suitable pcrlock files for various types of resources.</para>
  </refsect1>

  <refsect1>
    <title>Well-known Components</title>

    <para>Components of the boot process may be defined freely by the administrator or OS vendor. The
    following components are well-known however, and are defined by systemd. The list below is useful for
    ordering local pcrlock files properly against these components of the boot.</para>

    <variablelist>

      <varlistentry>
        <term><filename>240-secureboot-policy.pcrlock</filename></term>

        <listitem><para>The SecureBoot policy, as recorded to PCR 7. May be generated via
        <command>systemd-pcrlock lock-secureboot-policy</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>250-firmware-code-early.pcrlock</filename></term>

        <listitem><para>Firmware code measurements, as recorded to PCR 0 and 2, up to the separator
        measurement (see <filename>400-secureboot-separator.pcrlock</filename> below). May be generated via
        <command>systemd-pcrlock lock-firmware-code</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>250-firmware-config-early.pcrlock</filename></term>

        <listitem><para>Firmware configuration measurements, as recorded to PCR 1 and 3, up to the separator
        measurement (see <filename>400-secureboot-separator.pcrlock</filename> below). May be generated via
        <command>systemd-pcrlock lock-firmware-config</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>350-action-efi-application.pcrlock</filename></term>

        <listitem><para>The EFI "Application" measurement done once by the firmware. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>400-secureboot-separator.pcrlock</filename></term>

        <listitem><para>The EFI "separator" measurement on PCR 7 done once by the firmware to indicate where
        firmware control transitions into boot loader/OS control. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>500-separator.pcrlock</filename></term>

        <listitem><para>The EFI "separator" measurements on PCRs 0-6 done once by the firmware to indicate
        where firmware control transitions into boot loader/OS control. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>550-firmware-code-late.pcrlock</filename></term>

        <listitem><para>Firmware code measurements, as recorded to PCR 0 and 2, after the separator
        measurement (see <filename>400-secureboot-separator.pcrlock</filename> above). May be generated via
        <command>systemd-pcrlock lock-firmware-code</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>550-firmware-config-late.pcrlock</filename></term>

        <listitem><para>Firmware configuration measurements, as recorded to PCR 1 and 3, after the separator
        measurement (see <filename>400-secureboot-separator.pcrlock</filename> above). May be generated via
        <command>systemd-pcrlock lock-firmware-config</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>600-gpt.pcrlock</filename></term>

        <listitem><para>The GPT partition table of the booted medium, as recorded to PCR 5 by the
        firmware. May be generated via <command>systemd-pcrlock lock-gpt</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>620-secureboot-authority.pcrlock</filename></term>

        <listitem><para>The SecureBoot authority, as recorded to PCR 7. May be generated via
        <command>systemd-pcrlock lock-secureboot-authority</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>700-action-efi-exit-boot-services.pcrlock</filename></term>

        <listitem><para>The EFI action generated when <function>ExitBootServices()</function> is generated,
        i.e. when the UEFI environment is left and the OS takes over. Covers the PCR 5 measurement. Statically
        defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>710-kernel-cmdline.pcrlock</filename></term>

        <listitem><para>The kernel command line, as measured by the Linux kernel to PCR 9. May be generated
        via <command>systemd-pcrlock lock-kernel-cmdline</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>720-kernel-initrd.pcrlock</filename></term>

        <listitem><para>The kernel initrd, as measured by the Linux kernel to PCR 9. May be generated
        via <command>systemd-pcrlock lock-kernel-initrd</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>750-enter-initrd.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 11
        <citerefentry><refentrytitle>systemd-pcrphase-initrd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes when the initrd initializes. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>800-leave-initrd.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 11
        <citerefentry><refentrytitle>systemd-pcrphase-initrd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes when the initrd finishes. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>820-machine-id.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 15
        <citerefentry><refentrytitle>systemd-pcrmachine.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes at boot, covering <filename>/etc/machine-id</filename> contents. May be generated via
        <command>systemd-pcrlock lock-machine-id</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>830-root-file-system.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 15
        <citerefentry><refentrytitle>systemd-pcrfs-root.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes at boot, covering the root file system identity. May be generated
        via <command>systemd-pcrlock lock-file-system</command>.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>850-sysinit.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 11
        <citerefentry><refentrytitle>systemd-pcrphase-sysinit.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes when the main userspace did basic initialization and will now proceed to start regular system
        services. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>900-ready.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 11
        <citerefentry><refentrytitle>systemd-pcrphase.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes when the system fully booted up. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>950-shutdown.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 11
        <citerefentry><refentrytitle>systemd-pcrphase.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes when the system begins shutdown. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><filename>990-final.pcrlock</filename></term>

        <listitem><para>The measurement to PCR 11
        <citerefentry><refentrytitle>systemd-pcrphase-sysinit.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        makes when the system is close to finishing shutdown. Statically defined.</para>

        <xi:include href="version-info.xml" xpointer="v255"/></listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para><simplelist type="inline">
      <member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>systemd-pcrlock</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
    </simplelist></para>
  </refsect1>

</refentry>