systemd.pcrlock(5) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | WELL-KNOWN COMPONENTS | SEE ALSO | NOTES | COLOPHON

SYSTEMD.PCRLOCK(5)           systemd.pcrlock          SYSTEMD.PCRLOCK(5)

NAME         top

       systemd.pcrlock, systemd.pcrlock.d - PCR measurement prediction
       files

SYNOPSIS         top

           /etc/pcrlock.d/*.pcrlock
           /etc/pcrlock.d/*.pcrlock.d/*.pcrlock
           /run/pcrlock.d/*.pcrlock
           /run/pcrlock.d/*.pcrlock.d/*.pcrlock
           /var/lib/pcrlock.d/*.pcrlock
           /var/lib/pcrlock.d/*.pcrlock.d/*.pcrlock
           /usr/local/pcrlock.d/*.pcrlock
           /usr/local/pcrlock.d/*.pcrlock.d/*.pcrlock
           /usr/lib/pcrlock.d/*.pcrlock
           /usr/lib/pcrlock.d/*.pcrlock.d/*.pcrlock

DESCRIPTION         top

       *.pcrlock files define expected TPM2 PCR measurements of
       components involved in the boot process.  systemd-pcrlock(1) uses
       such pcrlock files to analyze and predict TPM2 PCR measurements.
       The pcrlock files are JSON arrays that follow a subset of the TCG
       Canonical Event Log Format (CEL-JSON)[1] specification.
       Specifically the "recnum", "content", and "content_type" 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.

       *.pcrlock files may be placed in various .d/ 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
       "NNN-component.pcrlock" (where NNN is a three-digit decimal
       number), for example 750-enter-initrd.pcrlock.

       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 *.pcrlock.d/*.pcrlock in the drop-in dirs,
       i.e. a common directory for a specific component, that contains
       one or more pcrlock files each covering one variant of the
       component. Example:
       650-kernel.pcrlock.d/6.5.5-200.fc38.x86_64.pcrlock and
       650-kernel.pcrlock.d/6.5.7-100.fc38.x86_64.pcrlock

       Use systemd-pcrlock list-components to list all pcrlock files
       currently installed.

       Use the various lock-* commands of systemd-pcrlock to
       automatically generate suitable pcrlock files for various types
       of resources.

WELL-KNOWN COMPONENTS         top

       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.

       240-secureboot-policy.pcrlock
           The SecureBoot policy, as recorded to PCR 7. May be generated
           via systemd-pcrlock lock-secureboot-policy.

           Added in version 255.

       250-firmware-code-early.pcrlock
           Firmware code measurements, as recorded to PCR 0 and 2, up to
           the separator measurement (see
           400-secureboot-separator.pcrlock below). May be generated via
           systemd-pcrlock lock-firmware-code.

           Added in version 255.

       250-firmware-config-early.pcrlock
           Firmware configuration measurements, as recorded to PCR 1 and
           3, up to the separator measurement (see
           400-secureboot-separator.pcrlock below). May be generated via
           systemd-pcrlock lock-firmware-config.

           Added in version 255.

       350-action-efi-application.pcrlock
           The EFI "Application" measurement done once by the firmware.
           Statically defined.

           Added in version 255.

       400-secureboot-separator.pcrlock
           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.

           Added in version 255.

       500-separator.pcrlock
           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.

           Added in version 255.

       550-firmware-code-late.pcrlock
           Firmware code measurements, as recorded to PCR 0 and 2, after
           the separator measurement (see
           400-secureboot-separator.pcrlock above). May be generated via
           systemd-pcrlock lock-firmware-code.

           Added in version 255.

       550-firmware-config-late.pcrlock
           Firmware configuration measurements, as recorded to PCR 1 and
           3, after the separator measurement (see
           400-secureboot-separator.pcrlock above). May be generated via
           systemd-pcrlock lock-firmware-config.

           Added in version 255.

       600-gpt.pcrlock
           The GPT partition table of the booted medium, as recorded to
           PCR 5 by the firmware. May be generated via systemd-pcrlock
           lock-gpt.

           Added in version 255.

       620-secureboot-authority.pcrlock
           The SecureBoot authority, as recorded to PCR 7. May be
           generated via systemd-pcrlock lock-secureboot-authority.

           Added in version 255.

       700-action-efi-exit-boot-services.pcrlock
           The EFI action generated when ExitBootServices() is
           generated, i.e. when the UEFI environment is left and the OS
           takes over. Covers the PCR 5 measurement. Statically defined.

           Added in version 255.

       710-kernel-cmdline.pcrlock
           The kernel command line, as measured by the Linux kernel to
           PCR 9. May be generated via systemd-pcrlock
           lock-kernel-cmdline.

           Added in version 255.

       720-kernel-initrd.pcrlock
           The kernel initrd, as measured by the Linux kernel to PCR 9.
           May be generated via systemd-pcrlock lock-kernel-initrd.

           Added in version 255.

       750-enter-initrd.pcrlock
           The measurement to PCR 11 systemd-pcrphase-initrd.service(8)
           makes when the initrd initializes. Statically defined.

           Added in version 255.

       800-leave-initrd.pcrlock
           The measurement to PCR 11 systemd-pcrphase-initrd.service(8)
           makes when the initrd finishes. Statically defined.

           Added in version 255.

       820-machine-id.pcrlock
           The measurement to PCR 15 systemd-pcrmachine.service(8) makes
           at boot, covering /etc/machine-id contents. May be generated
           via systemd-pcrlock lock-machine-id.

           Added in version 255.

       830-root-file-system.pcrlock
           The measurement to PCR 15 systemd-pcrfs-root.service(8) makes
           at boot, covering the root file system identity. May be
           generated via systemd-pcrlock lock-file-system.

           Added in version 255.

       850-sysinit.pcrlock
           The measurement to PCR 11 systemd-pcrphase-sysinit.service(8)
           makes when the main userspace did basic initialization and
           will now proceed to start regular system services. Statically
           defined.

           Added in version 255.

       900-ready.pcrlock
           The measurement to PCR 11 systemd-pcrphase.service(8) makes
           when the system fully booted up. Statically defined.

           Added in version 255.

       950-shutdown.pcrlock
           The measurement to PCR 11 systemd-pcrphase.service(8) makes
           when the system begins shutdown. Statically defined.

           Added in version 255.

       990-final.pcrlock
           The measurement to PCR 11 systemd-pcrphase-sysinit.service(8)
           makes when the system is close to finishing shutdown.
           Statically defined.

           Added in version 255.

SEE ALSO         top

       systemd(1), systemd-pcrlock(1)

NOTES         top

        1. TCG Canonical Event Log Format (CEL-JSON)
           https://trustedcomputinggroup.org/resource/canonical-event-log-format/

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2024-06-14.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2024-06-13.)  If you discover any rendering
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       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 257~devel                                     SYSTEMD.PCRLOCK(5)

Pages that refer to this page: systemd.directives(7)systemd.index(7)systemd-pcrlock(8)