SYSTEMD-TPM2-SETUP.SERVICE(8)

NAME
systemd-tpm2-setup.service, systemd-tpm2-setup-early.service, systemd-tpm2-setup - Set up the TPM2 Storage Root Key (SRK) and initialize NvPCRs at boot

SYNOPSIS

systemd-tpm2-setup.service

/usr/lib/systemd/systemd-tpm2-setup

DESCRIPTION

systemd-tpm2-setup.service and systemd-tpm2-setup-early.service are services that generate the Storage Root Key (SRK) if it has not been generated yet, and stores it in the TPM. If NvPCRs (additional PCR registers in TPM NV Indexes) are defined, these are initialized with the anchoring secret.

The services will store the public key of the SRK key pair in a PEM file in /run/systemd/tpm2-srk-public-key.pem and /var/lib/systemd/tpm2-srk-public-key.pem. They will also store it in TPM2B_PUBLIC format in /run/systemd/tpm2-srk-public-key.tpm2_public and /var/lib/systemd/tpm2-srk-public-key.tpm2b_public.

systemd-tpm2-setup-early.service runs very early at boot (possibly in the initrd), and writes the SRK public key to /run/systemd/tpm2-srk-public-key.* (as /var/ is generally not accessible this early yet), while systemd-tpm2-setup.service runs during a later boot phase and saves the public key to /var/lib/systemd/tpm2-srk-public-key.*.

FILES

/run/systemd/tpm2-srk-public-key.pem, /run/systemd/tpm2-srk-public-key.tpm2b_public
    The SRK public key in PEM and TPM2B_PUBLIC format, written during early boot.

    Added in version 255.

/var/lib/systemd/tpm2-srk-public-key.pem, /var/lib/systemd/tpm2-srk-public-key.tpm2_public
    The SRK public key in PEM and TPM2B_PUBLIC format, written during later boot (once /var/ is available).

    Added in version 255.

/usr/lib/nvpcr/*.nvpcr
    Definition files for NvPCRs.

    Added in version 259.

/run/credentials/@encrypted/nvpcr-anchor.*
    Encrypted NvPCR anchor secret, received into the system via system credentials.

    Added in version 259.

$BOOT/loader/credentials/nvpcr-anchor.*.cred
    Encrypted NvPCR anchor secret, to be picked up by the kernel loader stub, i.e. systemd-stub(7).

    Added in version 259.

SEE ALSO

systemd(1)