Provided by: systemd-cryptsetup_256.5-2ubuntu3_amd64 bug

NAME

       systemd-cryptenroll - Enroll PKCS#11, FIDO2, TPM2 token/devices to LUKS2 encrypted volumes

SYNOPSIS

       systemd-cryptenroll [OPTIONS...] [DEVICE]

DESCRIPTION

       systemd-cryptenroll is a tool for enrolling hardware security tokens and devices into a
       LUKS2 encrypted volume, which may then be used to unlock the volume during boot.
       Specifically, it supports tokens and credentials of the following kind to be enrolled:

        1. PKCS#11 security tokens and smartcards that may carry an RSA or EC key pair (e.g.
           various YubiKeys)

        2. FIDO2 security tokens that implement the "hmac-secret" extension (most FIDO2 keys,
           including YubiKeys)

        3. TPM2 security devices

        4. Regular passphrases

        5. Recovery keys. These are similar to regular passphrases, however are randomly
           generated on the computer and thus generally have higher entropy than user-chosen
           passphrases. Their character set has been designed to ensure they are easy to type in,
           while having high entropy. They may also be scanned off screen using QR codes.
           Recovery keys may be used for unlocking LUKS2 volumes wherever passphrases are
           accepted. They are intended to be used in combination with an enrolled hardware
           security token, as a recovery option when the token is lost.

       In addition, the tool may be used to enumerate currently enrolled security tokens and wipe
       a subset of them. The latter may be combined with the enrollment operation of a new
       security token, in order to update or replace enrollments.

       The tool supports only LUKS2 volumes, as it stores token meta-information in the LUKS2
       JSON token area, which is not available in other encryption formats.

       systemd-cryptsetup operates on the device backing /var/ if no device is specified
       explicitly, and no wipe operation is requested. (Note that in the typical case where /var/
       is on the same file system as the root file system, this hence enrolls a key into the
       backing device of the root file system.)

   TPM2 PCRs and policies
       PCRs allow binding of the encryption of secrets to specific software versions and system
       state, so that the enrolled key is only accessible (may be "unsealed") if specific trusted
       software and/or configuration is used. Such bindings may be created with the option
       --tpm2-pcrs= described below.

       Secrets may also be bound indirectly: a signed policy for a state of some combination of
       PCR values is provided, and the secret is bound to the public part of the key used to sign
       this policy. This means that the owner of a key can generate a sequence of signed
       policies, for specific software versions and system states, and the secret can be
       decrypted as long as the machine state matches one of those policies. For example, a
       vendor may provide such a policy for each kernel+initrd update, allowing users to encrypt
       secrets so that they can be decrypted when running any kernel+initrd signed by the vendor.
       Such bindings may be created with the options --tpm2-public-key=, --tpm2-public-key-pcrs=,
       --tpm2-signature= described below.

       See Linux TPM PCR Registry[1] for an authoritative list of PCRs and how they are updated.
       The table below contains a quick reference, describing in particular the PCRs modified by
       systemd.

       Table 1. Well-known PCR Definitions
       ┌────┬─────────────────────┬──────────────────────────┐
       │PCRnameExplanation              │
       ├────┼─────────────────────┼──────────────────────────┤
       │0   │ platform-code       │ Core system firmware     │
       │    │                     │ executable code; changes │
       │    │                     │ on firmware updates      │
       ├────┼─────────────────────┼──────────────────────────┤
       │1   │ platform-config     │ Core system firmware     │
       │    │                     │ data/host platform       │
       │    │                     │ configuration; typically │
       │    │                     │ contains serial and      │
       │    │                     │ model numbers, changes   │
       │    │                     │ on basic                 │
       │    │                     │ hardware/CPU/RAM         │
       │    │                     │ replacements             │
       ├────┼─────────────────────┼──────────────────────────┤
       │2   │ external-code       │ Extended or pluggable    │
       │    │                     │ executable code;         │
       │    │                     │ includes option ROMs on  │
       │    │                     │ pluggable hardware       │
       ├────┼─────────────────────┼──────────────────────────┤
       │3   │ external-config     │ Extended or pluggable    │
       │    │                     │ firmware data; includes  │
       │    │                     │ information about        │
       │    │                     │ pluggable hardware       │
       ├────┼─────────────────────┼──────────────────────────┤
       │4   │ boot-loader-code    │ Boot loader and          │
       │    │                     │ additional drivers, PE   │
       │    │                     │ binaries invoked by the  │
       │    │                     │ boot loader; changes on  │
       │    │                     │ boot loader updates. sd- │
       │    │                     │ stub(7) measures system  │
       │    │                     │ extension images read    │
       │    │                     │ from the ESP here too    │
       │    │                     │ (see systemd-sysext(8)). │
       ├────┼─────────────────────┼──────────────────────────┤
       │5   │ boot-loader-config  │ GPT/Partition table;     │
       │    │                     │ changes when the         │
       │    │                     │ partitions are added,    │
       │    │                     │ modified, or removed     │
       ├────┼─────────────────────┼──────────────────────────┤
       │7   │ secure-boot-policy  │ Secure Boot state;       │
       │    │                     │ changes when UEFI        │
       │    │                     │ SecureBoot mode is       │
       │    │                     │ enabled/disabled, or     │
       │    │                     │ firmware certificates    │
       │    │                     │ (PK, KEK, db, dbx, ...)  │
       │    │                     │ changes.                 │
       ├────┼─────────────────────┼──────────────────────────┤
       │9   │ kernel-initrd       │ The Linux kernel         │
       │    │                     │ measures all initrds it  │
       │    │                     │ receives into this PCR.  │
       ├────┼─────────────────────┼──────────────────────────┤
       │10  │ ima                 │ The IMA project measures │
       │    │                     │ its runtime state into   │
       │    │                     │ this PCR.                │
       ├────┼─────────────────────┼──────────────────────────┤
       │11  │ kernel-boot         │ systemd-stub(7) measures │
       │    │                     │ the ELF kernel image,    │
       │    │                     │ embedded initrd and      │
       │    │                     │ other payload of the PE  │
       │    │                     │ image it is placed in    │
       │    │                     │ into this PCR. systemd-  │
       │    │                     │ pcrphase.service(8)      │
       │    │                     │ measures boot phase      │
       │    │                     │ strings into this PCR at │
       │    │                     │ various milestones of    │
       │    │                     │ the boot process.        │
       ├────┼─────────────────────┼──────────────────────────┤
       │12  │ kernel-config       │ systemd-boot(7) measures │
       │    │                     │ the kernel command line  │
       │    │                     │ into this PCR. systemd-  │
       │    │                     │ stub(7) measures any     │
       │    │                     │ manually specified       │
       │    │                     │ kernel command line      │
       │    │                     │ (i.e. a kernel command   │
       │    │                     │ line that overrides the  │
       │    │                     │ one embedded in the      │
       │    │                     │ unified PE image) and    │
       │    │                     │ loaded credentials into  │
       │    │                     │ this PCR.                │
       ├────┼─────────────────────┼──────────────────────────┤
       │13  │ sysexts             │ systemd-stub(7) measures │
       │    │                     │ any systemd-sysext(8)    │
       │    │                     │ images it passes to the  │
       │    │                     │ booted kernel into this  │
       │    │                     │ PCR.                     │
       ├────┼─────────────────────┼──────────────────────────┤
       │14  │ shim-policy         │ The shim project         │
       │    │                     │ measures its "MOK"       │
       │    │                     │ certificates and hashes  │
       │    │                     │ into this PCR.           │
       ├────┼─────────────────────┼──────────────────────────┤
       │15  │ system-identity     │ systemd-cryptsetup(8)    │
       │    │                     │ optionally measures the  │
       │    │                     │ volume key of activated  │
       │    │                     │ LUKS volumes into this   │
       │    │                     │ PCR. systemd-            │
       │    │                     │ pcrmachine.service(8)    │
       │    │                     │ measures the machine-    │
       │    │                     │ id(5) into this PCR.     │
       │    │                     │ systemd-                 │
       │    │                     │ pcrfs@.service(8)        │
       │    │                     │ measures mount points,   │
       │    │                     │ file system UUIDs,       │
       │    │                     │ labels, partition UUIDs  │
       │    │                     │ of the root and /var/    │
       │    │                     │ filesystems into this    │
       │    │                     │ PCR.                     │
       ├────┼─────────────────────┼──────────────────────────┤
       │16  │ debug               │ Debug                    │
       ├────┼─────────────────────┼──────────────────────────┤
       │23  │ application-support │ Application Support      │
       └────┴─────────────────────┴──────────────────────────┘

       In general, encrypted volumes would be bound to some combination of PCRs 7, 11, and 14 (if
       shim/MOK is used). In order to allow firmware and OS version updates, it is typically not
       advisable to use PCRs such as 0 and 2, since the program code they cover should already be
       covered indirectly through the certificates measured into PCR 7. Validation through
       certificates hashes is typically preferable over validation through direct measurements as
       it is less brittle in context of OS/firmware updates: the measurements will change on
       every update, but signatures should remain unchanged. See the Linux TPM PCR Registry[1]
       for more discussion.

LIMITATIONS

       Note that currently when enrolling a new key of one of the five supported types listed
       above, it is required to first provide a passphrase, a recovery key, a FIDO2 token, or a
       TPM2 key. It's currently not supported to unlock a device with a PKCS#11 key in order to
       enroll a new PKCS#11 key. Thus, if in future key roll-over is desired it's generally
       recommended to ensure a passphrase, a recovery key, a FIDO2 token, or a TPM2 key is always
       enrolled.

       Also note that support for enrolling multiple FIDO2 tokens is currently limited. When
       multiple FIDO2 tokens are enrolled, systemd-cryptsetup will perform pre-flight requests to
       attempt to identify which of the enrolled tokens are currently plugged in. However, this
       is not possible for FIDO2 tokens with user verification (UV, usually via biometrics), in
       which case it will fall back to attempting each enrolled token one by one. This will
       result in multiple prompts for PIN and user verification. This limitation does not apply
       to PKCS#11 tokens.

COMPATIBILITY

       Security technology both in systemd and in the general industry constantly evolves. In
       order to provide best security guarantees, the way TPM2, FIDO2, PKCS#11 devices are
       enrolled is regularly updated in newer versions of systemd. Whenever this happens the
       following compatibility guarantees are given:

       •   Old enrollments continue to be supported and may be unlocked with newer versions of
           systemd-cryptsetup@.service(8).

       •   The opposite is not guaranteed however: it might not be possible to unlock volumes
           with enrollments done with a newer version of systemd-cryptenroll with an older
           version of systemd-cryptsetup.

       That said, it is generally recommended to use matching versions of systemd-cryptenroll and
       systemd-cryptsetup, since this is best tested and supported.

       It might be advisable to re-enroll existing enrollments to take benefit of newer security
       features, as they are added to systemd.

OPTIONS

       The following options are understood:

       --password
           Enroll a regular password/passphrase. This command is mostly equivalent to cryptsetup
           luksAddKey, however may be combined with --wipe-slot= in one call, see below.

           Added in version 248.

       --recovery-key
           Enroll a recovery key. Recovery keys are mostly identical to passphrases, but are
           computer-generated instead of being chosen by a human, and thus have a guaranteed high
           entropy. The key uses a character set that is easy to type in, and may be scanned off
           screen via a QR code.

           Added in version 248.

       --unlock-key-file=PATH
           Use a file instead of a password/passphrase read from stdin to unlock the volume.
           Expects the PATH to the file containing your key to unlock the volume. Currently there
           is nothing like --key-file-offset= or --key-file-size= so this file has to only
           contain the full key.

           Added in version 252.

       --unlock-fido2-device=PATH
           Use a FIDO2 device instead of a password/passphrase read from stdin to unlock the
           volume. Expects a hidraw device referring to the FIDO2 device (e.g.  /dev/hidraw1).
           Alternatively the special value "auto" may be specified, in order to automatically
           determine the device node of a currently plugged in security token (of which there
           must be exactly one). This automatic discovery is unsupported if --fido2-device=
           option is also specified.

           Added in version 253.

       --unlock-tpm2-device=PATH
           Use a TPM2 device instead of a password/passhprase read from stdin to unlock the
           volume. Expects a device node path referring to the TPM2 chip (e.g.  /dev/tpmrm0).
           Alternatively the special value "auto" may be specified, in order to automatically
           determine the device node of a currently discovered TPM2 device (of which there must
           be exactly one).

           Added in version 256.

       --pkcs11-token-uri=URI
           Enroll a PKCS#11 security token or smartcard (e.g. a YubiKey). Expects a PKCS#11 URI
           that allows finding an X.509 certificate or a public key on the token. The URI must
           also be suitable to find a related private key after changing the type of object in
           it. Alternatively the special value "auto" may be specified, in order to automatically
           determine the suitable URI if a single security token containing a single key pair is
           plugged in. The special value "list" may be used to enumerate all suitable PKCS#11
           tokens currently plugged in.

           The PKCS#11 token must contain an RSA or EC key pair which will be used to unlock a
           LUKS2 volume. For RSA, a randomly generated volume key is encrypted with a public key
           in the token, and stored in the LUKS2 JSON token header area. To unlock a volume, the
           stored encrypted volume key will be decrypted with a private key in the token. For
           ECC, ECDH algorithm is used: we generate a pair of EC keys in the same EC group, then
           derive a shared secret using the generated private key and the public key in the
           token. The derived shared secret is used as a volume key. The generated public key is
           stored in the LUKS2 JSON token header area. The generated private key is erased. To
           unlock a volume, we derive the shared secret with the stored public key and a private
           key in the token.

           In order to unlock a LUKS2 volume with an enrolled PKCS#11 security token, specify the
           pkcs11-uri= option in the respective /etc/crypttab line:

               myvolume /dev/sda1 - pkcs11-uri=auto

           See crypttab(5) for a more comprehensive example of a systemd-cryptenroll invocation
           and its matching /etc/crypttab line.

           Added in version 248.

       --fido2-credential-algorithm=STRING
           Specify COSE algorithm used in credential generation. The default value is "es256".
           Supported values are "es256", "rs256" and "eddsa".

           "es256" denotes ECDSA over NIST P-256 with SHA-256.  "rs256" denotes 2048-bit RSA with
           PKCS#1.5 padding and SHA-256.  "eddsa" denotes EDDSA over Curve25519 with SHA-512.

           Note that your authenticator may choose not to support some algorithms.

           Added in version 251.

       --fido2-device=PATH
           Enroll a FIDO2 security token that implements the "hmac-secret" extension (e.g. a
           YubiKey). Expects a hidraw device referring to the FIDO2 device (e.g.  /dev/hidraw1).
           Alternatively the special value "auto" may be specified, in order to automatically
           determine the device node of a currently plugged in security token (of which there
           must be exactly one). This automatic discovery is unsupported if
           --unlock-fido2-device= option is also specified. The special value "list" may be used
           to enumerate all suitable FIDO2 tokens currently plugged in. Note that many hardware
           security tokens that implement FIDO2 also implement the older PKCS#11 standard.
           Typically FIDO2 is preferable, given it's simpler to use and more modern.

           In order to unlock a LUKS2 volume with an enrolled FIDO2 security token, specify the
           fido2-device= option in the respective /etc/crypttab line:

               myvolume /dev/sda1 - fido2-device=auto

           See crypttab(5) for a more comprehensive example of a systemd-cryptenroll invocation
           and its matching /etc/crypttab line.

           Added in version 248.

       --fido2-with-client-pin=BOOL
           When enrolling a FIDO2 security token, controls whether to require the user to enter a
           PIN when unlocking the volume (the FIDO2 "clientPin" feature). Defaults to "yes".
           (Note: this setting is without effect if the security token does not support the
           "clientPin" feature at all, or does not allow enabling or disabling it.)

           Added in version 249.

       --fido2-with-user-presence=BOOL
           When enrolling a FIDO2 security token, controls whether to require the user to verify
           presence (tap the token, the FIDO2 "up" feature) when unlocking the volume. Defaults
           to "yes". (Note: this setting is without effect if the security token does not support
           the "up" feature at all, or does not allow enabling or disabling it.)

           Added in version 249.

       --fido2-with-user-verification=BOOL
           When enrolling a FIDO2 security token, controls whether to require user verification
           when unlocking the volume (the FIDO2 "uv" feature). Defaults to "no". (Note: this
           setting is without effect if the security token does not support the "uv" feature at
           all, or does not allow enabling or disabling it.)

           Added in version 249.

       --tpm2-device=PATH
           Enroll a TPM2 security chip. Expects a device node path referring to the TPM2 chip
           (e.g.  /dev/tpmrm0). Alternatively the special value "auto" may be specified, in order
           to automatically determine the device node of a currently discovered TPM2 device (of
           which there must be exactly one). The special value "list" may be used to enumerate
           all suitable TPM2 devices currently discovered.

           In order to unlock a LUKS2 volume with an enrolled TPM2 security chip, specify the
           tpm2-device= option in the respective /etc/crypttab line:

               myvolume /dev/sda1 - tpm2-device=auto

           See crypttab(5) for a more comprehensive example of a systemd-cryptenroll invocation
           and its matching /etc/crypttab line.

           Use --tpm2-pcrs= (see below) to configure which TPM2 PCR indexes to bind the
           enrollment to.

           Added in version 248.

       --tpm2-device-key=PATH
           Enroll a TPM2 security chip using its public key. Expects a path referring to the TPM2
           public key in TPM2B_PUBLIC format. This cannot be used with --tpm2-device=, as it
           performs the same operation, but without connecting to the TPM2 security chip; instead
           the enrollment is calculated using the provided TPM2 key. This is useful in situations
           where the TPM2 security chip is not available at the time of enrollment.

           The key, in most cases, should be the Storage Root Key (SRK) from a local TPM2
           security chip. If a key from a different handle (not the SRK) is used, you must
           specify its handle index using --tpm2-seal-key-handle=.

           The systemd-tpm2-setup.service(8) service writes the SRK to
           /run/systemd/tpm2-srk-public-key.tpm2b_public automatically during boot, in the
           correct format.

           Alternatively, you may use systemd-analyze srk to retrieve the SRK from the TPM2
           security chip explicitly. See systemd-analyze(1) for details. Example:

               systemd-analyze srk > srk.tpm2b_public

           Added in version 255.

       --tpm2-seal-key-handle=HANDLE
           Configures which parent key to use for sealing, using the TPM handle (index) of the
           key. This is used to "seal" (encrypt) a secret and must be used later to "unseal"
           (decrypt) the secret. Expects a hexadecimal 32bit integer, optionally prefixed with
           "0x". Allowable values are any handle index in the persistent
           ("0x81000000"-"0x81ffffff") or transient ("0x80000000"-"0x80ffffff") ranges. Since
           transient handles are lost after a TPM reset, and may be flushed during TPM context
           switching, they should not be used except for very specific use cases, e.g. testing.

           The default is the Storage Root Key (SRK) handle index "0x81000001". A value of 0 will
           use the default. For the SRK handle, a new key will be created and stored in the TPM
           if one does not already exist; for any other handle, the key must already exist in the
           TPM at the specified handle index.

           This should not be changed unless you know what you are doing.

           Added in version 255.

       --tpm2-pcrs=PCR[+PCR...]
           Configures the TPM2 PCRs (Platform Configuration Registers) to bind to when enrollment
           is requested via --tpm2-device=. Takes a list of PCR entries, where each entry starts
           with a name or numeric index in the range 0...23, optionally followed by ":" and a
           hash algorithm name (specifying the PCR bank), optionally followed by "=" and a hash
           digest value. Multiple PCR entries are separated by "+". If not specified, the default
           is to use PCR 7 only. If an empty string is specified, binds the enrollment to no PCRs
           at all. See the table above for a list of available PCRs.

           Example: --tpm2-pcrs=boot-loader-code+platform-config+boot-loader-config specifies
           that PCR registers 4, 1, and 5 should be used.

           Example: --tpm2-pcrs=7:sha256 specifies that PCR register 7 from the SHA256 bank
           should be used.

           Example: --tpm2-pcrs=4:sha1=3a3f780f11a4b49969fcaa80cd6e3957c33b2275 specifies that
           PCR register 4 from the SHA1 bank should be used, and a hash digest value of
           3a3f780f11a4b49969fcaa80cd6e3957c33b2275 will be used instead of reading the current
           PCR value.

           Added in version 248.

       --tpm2-with-pin=BOOL
           When enrolling a TPM2 device, controls whether to require the user to enter a PIN when
           unlocking the volume in addition to PCR binding, based on TPM2 policy authentication.
           Defaults to "no". Despite being called PIN, any character can be used, not just
           numbers.

           Note that incorrect PIN entry when unlocking increments the TPM dictionary attack
           lockout mechanism, and may lock out users for a prolonged time, depending on its
           configuration. The lockout mechanism is a global property of the TPM,
           systemd-cryptenroll does not control or configure the lockout mechanism. You may use
           tpm2-tss tools to inspect or configure the dictionary attack lockout, with
           tpm2_getcap(1) and tpm2_dictionarylockout(1) commands, respectively.

           Added in version 251.

       --tpm2-public-key=PATH, --tpm2-public-key-pcrs=PCR[+PCR...], --tpm2-signature=PATH
           Configures a TPM2 signed PCR policy to bind encryption to. The --tpm2-public-key=
           option accepts a path to a PEM encoded RSA public key, to bind the encryption to. If
           this is not specified explicitly, but a file tpm2-pcr-public-key.pem exists in one of
           the directories /etc/systemd/, /run/systemd/, /usr/lib/systemd/ (searched in this
           order), it is automatically used. The --tpm2-public-key-pcrs= option takes a list of
           TPM2 PCR indexes to bind to (same syntax as --tpm2-pcrs= described above). If not
           specified defaults to 11 (i.e. this binds the policy to any unified kernel image for
           which a PCR signature can be provided).

           Note the difference between --tpm2-pcrs= and --tpm2-public-key-pcrs=: the former binds
           decryption to the current, specific PCR values; the latter binds decryption to any set
           of PCR values for which a signature by the specified public key can be provided. The
           latter is hence more useful in scenarios where software updates shell be possible
           without losing access to all previously encrypted LUKS2 volumes. Like with
           --tpm2-pcrs=, names defined in the table above can also be used to specify the
           registers, for instance --tpm2-public-key-pcrs=boot-loader-code+system-identity.

           The --tpm2-signature= option takes a path to a TPM2 PCR signature file as generated by
           the systemd-measure(1) tool. If this is not specified explicitly, a suitable signature
           file tpm2-pcr-signature.json is searched for in /etc/systemd/, /run/systemd/,
           /usr/lib/systemd/ (in this order) and used. If a signature file is specified or found
           it is used to verify if the volume can be unlocked with it given the current PCR
           state, before the new slot is written to disk. This is intended as safety net to
           ensure that access to a volume is not lost if a public key is enrolled for which no
           valid signature for the current PCR state is available. If the supplied signature does
           not unlock the current PCR state and public key combination, no slot is enrolled and
           the operation will fail. If no signature file is specified or found no such safety
           verification is done.

           Added in version 252.

       --tpm2-pcrlock=PATH
           Configures a TPM2 pcrlock policy to bind encryption to. Expects a path to a pcrlock
           policy file as generated by the systemd-pcrlock(1) tool. If a TPM2 device is enrolled
           and this option is not used but a file pcrlock.json is found in /run/systemd/ or
           /var/lib/systemd/ it is automatically used. Assign an empty string to turn this
           behaviour off.

           Added in version 255.

       --wipe-slot=SLOT[,SLOT...]
           Wipes one or more LUKS2 key slots. Takes a comma separated list of numeric slot
           indexes, or the special strings "all" (for wiping all key slots), "empty" (for wiping
           all key slots that are unlocked by an empty passphrase), "password" (for wiping all
           key slots that are unlocked by a traditional passphrase), "recovery" (for wiping all
           key slots that are unlocked by a recovery key), "pkcs11" (for wiping all key slots
           that are unlocked by a PKCS#11 token), "fido2" (for wiping all key slots that are
           unlocked by a FIDO2 token), "tpm2" (for wiping all key slots that are unlocked by a
           TPM2 chip), or any combination of these strings or numeric indexes, in which case all
           slots matching either are wiped. As safety precaution an operation that wipes all
           slots without exception (so that the volume cannot be unlocked at all anymore, unless
           the volume key is known) is refused.

           This switch may be used alone, in which case only the requested wipe operation is
           executed. It may also be used in combination with any of the enrollment options listed
           above, in which case the enrollment is completed first, and only when successful the
           wipe operation executed — and the newly added slot is always excluded from the wiping.
           Combining enrollment and slot wiping may thus be used to update existing enrollments:

               systemd-cryptenroll /dev/sda1 --wipe-slot=tpm2 --tpm2-device=auto

           The above command will enroll the TPM2 chip, and then wipe all previously created TPM2
           enrollments on the LUKS2 volume, leaving only the newly created one. Combining wiping
           and enrollment may also be used to replace enrollments of different types, for example
           for changing from a PKCS#11 enrollment to a FIDO2 one:

               systemd-cryptenroll /dev/sda1 --wipe-slot=pkcs11 --fido2-device=auto

           Or for replacing an enrolled empty password by TPM2:

               systemd-cryptenroll /dev/sda1 --wipe-slot=empty --tpm2-device=auto

           Added in version 248.

       -h, --help
           Print a short help text and exit.

       --version
           Print a short version string and exit.

CREDENTIALS

       systemd-cryptenroll supports the service credentials logic as implemented by
       ImportCredential=/LoadCredential=/SetCredential= (see systemd.exec(5) for details). The
       following credentials are used when passed in:

       cryptenroll.passphrase, cryptenroll.new-passphrase
           May contain the passphrase to unlock the volume with/to newly enroll.

           Added in version 256.

       cryptenroll.tpm2-pin, cryptenroll.new-tpm2-pin
           May contain the TPM2 PIN to unlock the volume with/to newly enroll.

           Added in version 256.

       cryptenroll.fido2-pin
           If a FIDO2 token is enrolled this may contain the PIN of the token.

           Added in version 256.

       cryptenroll.pkcs11-pin
           If a PKCS#11 token is enrolled this may contain the PIN of the token.

           Added in version 256.

EXIT STATUS

       On success, 0 is returned, a non-zero failure code otherwise.

EXAMPLES

       crypttab(5) and systemd-measure(1) contain various examples employing systemd-cryptenroll.

SEE ALSO

       systemd(1), systemd-cryptsetup@.service(8), crypttab(5), cryptsetup(8), systemd-measure(1)

NOTES

        1. Linux TPM PCR Registry
           https://uapi-group.org/specifications/specs/linux_tpm_pcr_registry/