SYSTEMD-CRYPTENROLL(1) systemd-cryptenroll SYSTEMD-CRYPTENROLL(1)
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
┌─────┬─────────────────────┬───────────────────────┐
│ PCR │ name │ Explanation │
├─────┼─────────────────────┼───────────────────────┤
│ 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 is
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.
UNLOCKING
The following options are understood that may be used to unlock the
device in preparation of the enrollment operations:
--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. Note that currently FIDO2
devices enrolled without an accompanying LUKS2 token (i.e.
--fido2-parameters-in-header=no) cannot be used for unlocking.
Added in version 253.
--unlock-tpm2-device=PATH
Use a TPM2 device instead of a password/passphrase 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.
SIMPLE ENROLLMENT
The following options are understood that may be used to enroll simple
user input based unlocking:
--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.
PKCS#11 ENROLLMENT
The following option is understood that may be used to enroll PKCS#11
tokens:
--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 ENROLLMENT
The following options are understood that may be used to enroll FIDO2
tokens:
--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 is 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-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-salt-file=PATH
When enrolling a FIDO2 security token, specifies the path to a file
or an AF_UNIX socket from which we should read the salt value to be
used in the HMAC operation performed by the FIDO2 security token. If
this option is not specified, the salt will be randomly generated.
Added in version 257.
--fido2-parameters-in-header=BOOL
When enrolling a FIDO2 security token, controls whether to store
FIDO2 parameters in a token in the LUKS2 superblock. Defaults to
"yes". If set to "no", the fido2-cid= option has to be specified
manually in the respective /etc/crypttab line along with a key file.
See crypttab(5) for details.
Added in version 257.
--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 ENROLLMENT
The following options are understood that may be used to enroll TPM2
devices:
--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 shall 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(8)
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.
OTHER OPTIONS
The following additional options are understood:
--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 --unlock-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.
--list-devices
Show a list of candidate block devices this command may operate on.
Specifically, this enumerates block devices currently present that
contain a LUKS superblock, and shows their device node paths along
with any of their symlinks. The devices must implement the
hmac-secret extension to be useable.
Added in version 257.
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
--no-pager
Do not pipe output into a pager.
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/
systemd 257.9 SYSTEMD-CRYPTENROLL(1)
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