systemd.pcrlock, systemd.pcrlock.d — PCR measurement prediction files
/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
*.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 Common Event Log Format
(CEL-JSON) 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.pcrlockNNN 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.
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.
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.
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.
350-action-efi-application.pcrlock¶The EFI "Application" measurement done once by the firmware. Statically defined.
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.
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.
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.
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.
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.
The SecureBoot authority, as recorded to PCR 7. May be generated via systemd-pcrlock lock-secureboot-authority.
700-action-efi-exit-boot-services.pcrlock¶The EFI action generated when ExitBootServices() is generated,
i.e. the UEFI environment is left and the OS takes over. Covers the PCR 5 measurement. Statically
defined.
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.
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.
750-enter-initrd.pcrlock¶The measurement to PCR 11 systemd-pcrphase-initrd.service(8) makes when the initrd initializes. Statically defined.
800-leave-initrd.pcrlock¶The measurement to PCR 11 systemd-pcrphase-initrd.service(8) makes when the initrd finishes. Statically defined.
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.
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.
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.
900-ready.pcrlock¶The measurement to PCR 11 systemd-pcrphase.service(8) makes when the system fully booted up. Statically defined.
950-shutdown.pcrlock¶The measurement to PCR 11 systemd-pcrphase.service(8) makes when the system begins shutdown. Statically defined.
990-final.pcrlock¶The measurement to PCR 11 systemd-pcrphase-sysinit.service(8) makes when the system is close to finishing shutdown. Statically defined.