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CRYPTSETUP(8) Maintenance Commands CRYPTSETUP(8)
cryptsetup - utility for configuring and managing encrypted
storage devices
cryptsetup <action> [<options>] <action args>
Cryptsetup is a utility for configuring and managing full-disk
encryption on storage devices. It can encrypt block devices (such
as hard drives or partitions) and containers (disk images stored
as files).
When you unlock an encrypted volume, cryptsetup creates a new
device mapping that applications can access like any regular
storage device. The actual encryption and decryption work is
performed transparently by the kernel’s device-mapper dm-crypt
driver.
Cryptsetup works with two main volume types: plain encrypted
volumes and LUKS (Linux Unified Key Setup) volumes. Plain volumes
provide basic encryption, while LUKS volumes include a metadata
header that enables advanced features like multiple keyslots and
key management. Additionally, LUKS can be used to manage
hardware-based encryption on OPAL-capable storage drives.
Cryptsetup also provides limited support for volumes created by
other encryption systems, including loop-AES, TrueCrypt,
VeraCrypt, BitLocker, and FileVault2.
For more information about a specific cryptsetup action, see
cryptsetup-<action>(8), where <action> is the name of the
cryptsetup action.
Cryptsetup devices can be activated during boot through
crypttab(5), which is part of systemd(1) or other system init
scripts.
The following are valid actions for all supported device types.
OPEN
open <device> <name> --type <device_type>
Opens (creates a mapping with) <name> backed by device <device>.
See cryptsetup-open(8).
CLOSE
close <name>
Removes the existing mapping <name> and wipes the key from kernel
memory. See cryptsetup-close(8).
STATUS
status <name>
Reports the status for the mapping <name>. See
cryptsetup-status(8).
RESIZE
resize <name>
Resizes an active mapping <name>. See cryptsetup-resize(8).
REFRESH
refresh <name>
Refreshes parameters of active mapping <name>. See
cryptsetup-refresh(8).
REENCRYPT
reencrypt <device> or --active-name <name> [<new_name>]
Run LUKS device reencryption. See cryptsetup-reencrypt(8).
Plain dm-crypt encrypts the device sector-by-sector with a single,
non-salted hash of the passphrase. No checks are performed, and no
metadata is used. There is no formatting operation. When the raw
device is mapped (opened), the usual device operations can be used
on the mapped device, including filesystem creation. Mapped
devices usually reside in /dev/mapper/<name>.
The following are valid plain device type actions:
OPEN
open --type plain <device> <name>
create <name> <device> (OBSOLETE syntax)
Opens (creates a mapping with) <name> backed by device <device>.
See cryptsetup-open(8).
LUKS, the Linux Unified Key Setup, is a standard for disk
encryption. It adds a standardized header at the start of the
device, a keyslot area directly behind the header and the bulk
data area behind that. The whole set is called a 'LUKS container'.
The device that a LUKS container resides on is called a 'LUKS
device'. For most purposes, both terms can be used
interchangeably.
LUKS can manage multiple passphrases that can be individually
revoked or changed. Each passphrase uses an individual keyslot
containing a volume key for data encryption. Keyslots can be
securely scrubbed from persistent media due to the use of
anti-forensic stripes. Passphrases are protected against
brute-force attacks by the Password-Based Key Derivation Function
(PBKDF). A passphrase stored in a file is called a key file. The
only difference between a passphrase and a key file is that a key
file can contain binary data. Both are processed the same.
LUKS version 1 (or LUKS1) is the original metadata format, while
LUKS2 is a new version that allows additional extensions like
different PBKDF algorithms or authenticated encryption. You can
format the device with a specific LUKS version with --type luks1
or --type luks2 in the luksFormat command. Normally, you do not
need to specify any version as it is recognized automatically. The
default format is LUKS2.
The <device> parameter can also be specified by a LUKS UUID in the
format UUID=<uuid>.
The LUKS header can be detached from data (stored separately). To
specify a detached header, the --header parameter can be used in
all LUKS commands and always takes precedence over the positional
<device> parameter.
The following are valid LUKS actions:
FORMAT
luksFormat <device> [<key file>]
Initializes a LUKS partition and sets the initial passphrase (for
keyslot 0). See cryptsetup-luksFormat(8).
OPEN
open --type luks <device> <name>
luksOpen <device> <name> (old syntax)
Opens the LUKS device <device> and sets up a mapping <name> after
successful verification of the supplied passphrase. See
cryptsetup-open(8).
SUSPEND
luksSuspend <name>
Suspends an active device (all IO operations will block and
accesses to the device will wait indefinitely) and wipes the
encryption key from kernel memory. See cryptsetup-luksSuspend(8).
RESUME
luksResume <name>
Resumes a suspended device and reinstates the encryption key. See
cryptsetup-luksResume(8).
ADD KEY
luksAddKey <device> [<key file with new key>]
Adds a new passphrase using an existing passphrase. See
cryptsetup-luksAddKey(8).
REMOVE KEY
luksRemoveKey <device> [<key file with passphrase to be removed>]
Removes the supplied passphrase from the LUKS device. See
cryptsetup-luksRemoveKey(8).
CHANGE KEY
luksChangeKey <device> [<new key file>]
Changes an existing passphrase. See cryptsetup-luksChangeKey(8).
CONVERT KEY
luksConvertKey <device>
Converts an existing LUKS2 keyslot to new PBKDF parameters. See
cryptsetup-luksConvertKey(8).
KILL SLOT
luksKillSlot <device> <number>
Wipe the keyslot with the <number> from the LUKS device. See
cryptsetup-luksKillSlot(8).
ERASE
erase <device>
luksErase <device> (old syntax)
Erase all keyslots and make the LUKS container permanently
inaccessible. See cryptsetup-erase(8).
UUID
luksUUID <device>
Print or set the UUID of a LUKS device. See
cryptsetup-luksUUID(8).
IS LUKS
isLuks <device>
Returns true, if <device> is a LUKS device, false otherwise. See
cryptsetup-isLuks(8).
DUMP
luksDump <device>
Dump the header information of a LUKS device. See
cryptsetup-luksDump(8).
HEADER BACKUP
luksHeaderBackup <device> --header-backup-file <file>
Stores a binary backup of the LUKS header and keyslot area. See
cryptsetup-luksHeaderBackup(8).
HEADER RESTORE
luksHeaderRestore <device> --header-backup-file <file>
Restores a binary backup of the LUKS header and keyslot area from
the specified file. See cryptsetup-luksHeaderRestore(8).
TOKEN
token <add|remove|import|export> <device>
Manipulate token objects used for obtaining passphrases. See
cryptsetup-token(8).
CONVERT
convert <device> --type <format>
Converts the device between LUKS1 and LUKS2 format (if possible).
See cryptsetup-convert(8).
CONFIG
config <device>
Set permanent configuration options (store to LUKS header). See
cryptsetup-config(8).
Cryptsetup supports mapping a loop-AES encrypted partition using a
compatibility mode.
OPEN
open --type loopaes <device> <name> --key-file <keyfile>
loopaesOpen <device> <name> --key-file <keyfile> (old syntax)
Opens the loop-AES <device> and sets up a mapping <name>. See
cryptsetup-open(8).
See also section 7 of the FAQ and loop-AES
<http://loop-aes.sourceforge.net> for more information regarding
loop-AES.
Cryptsetup supports mapping of TrueCrypt, tcplay, or VeraCrypt
encrypted partitions using a native Linux kernel API. Header
formatting and TCRYPT header change are not supported; cryptsetup
never changes the TCRYPT header on-device.
TCRYPT extension requires the kernel userspace crypto API to be
available. If you are configuring the kernel yourself, enable
"User-space interface for symmetric key cipher algorithms" in
"Cryptographic API" section (CRYPTO_USER_API_SKCIPHER .config
option).
Because the TCRYPT header is encrypted, you must always provide a
valid passphrase and keyfiles.
Cryptsetup should recognize all header variants, except legacy
cipher chains using LRW encryption mode with a 64-bit encryption
block (namely, Blowfish in LRW mode is not recognized; this is a
limitation of the kernel crypto API).
VeraCrypt is an extension of TrueCrypt with an increased iteration
count, so unlocking can take quite a lot of time.
To open a VeraCrypt device with a custom Personal Iteration
Multiplier (PIM) value, use either the --veracrypt-pim PIM option
to directly specify the PIM on the command line or use
--veracrypt-query-pim to be prompted for the PIM.
The PIM value affects the number of iterations applied during key
derivation. Please refer to PIM
<https://veracrypt.io/en/Personal%20Iterations%20Multiplier%20(PIM).html>
for more detailed information.
If you need to disable VeraCrypt device support, use
--disable-veracrypt option.
Activation with tcryptOpen is supported only for cipher chains
using LRW or XTS encryption modes.
The tcryptDump command should work for all recognized TCRYPT
devices and doesn’t require superuser privilege.
To map the system device (device with boot loader where the whole
encrypted system resides), use --tcrypt-system option. Please read
specific info in cryptsetup-tcryptOpen(8) --tcrypt-system option
section as mapping system-encrypted device is tricky.
To use a hidden header (and map hidden device, if available), use
--tcrypt-hidden option.
To explicitly use the backup (secondary) header, use
--tcrypt-backup option.
There is no protection for a hidden volume if the outer volume is
mounted. The reason is that if there were any protection, it would
require some metadata describing what to protect in the outer
volume, and the hidden volume would become detectable.
OPEN
open --type tcrypt <device> <name>
tcryptOpen_ <device> <name> (old syntax)
Opens the TCRYPT (a TrueCrypt-compatible) <device> and sets up a
mapping <name>. See cryptsetup-open(8).
DUMP
tcryptDump <device>
Dump the header information of a TCRYPT device. See
cryptsetup-tcryptDump(8).
See also TrueCrypt <https://en.wikipedia.org/wiki/TrueCrypt> and
VeraCrypt <https://en.wikipedia.org/wiki/VeraCrypt> pages for more
information.
Please note that cryptsetup does not use TrueCrypt or VeraCrypt
code; please report all problems related to this compatibility
extension to the cryptsetup project.
Cryptsetup supports mapping of BitLocker and BitLocker to Go
encrypted partitions using a native Linux kernel API. Header
formatting and BITLK header changes are not supported; cryptsetup
never changes the BITLK header on-device.
BITLK extension requires the kernel userspace crypto API to be
available (for details, see the TCRYPT section).
Cryptsetup should recognize all BITLK header variants, except the
legacy header used in Windows Vista systems and partially
decrypted BitLocker devices. Activation of legacy devices
encrypted in CBC mode requires at least a Linux kernel version
5.3, and for devices using the Elephant diffuser, kernel 5.6.
The bitlkDump command should work for all recognized BITLK devices
and doesn’t require superuser privilege.
For unlocking with the open, a password, a recovery passphrase, or
a startup key must be provided.
Additionally, unlocking using the volume key is supported. You
must provide BitLocker Full Volume Encryption Key (FVEK) using the
--volume-key-file option. The key must be decrypted and without
the header (only 128/256/512 bits of key data depending on the
used cipher and mode).
Other unlocking methods (TPM, SmartCard) are not supported.
OPEN
open --type bitlk <device> <name>
bitlkOpen <device> <name> (old syntax)
Opens the BITLK (a BitLocker-compatible) <device> and sets up a
mapping <name>. See cryptsetup-open(8).
DUMP
bitlkDump <device>
Dump the header information of a BITLK device. See
cryptsetup-bitlkDump(8).
Please note that cryptsetup does not use any Windows BitLocker
code; please report all problems related to this compatibility
extension to the cryptsetup project.
Cryptsetup supports the mapping of FileVault2 (FileVault2
full-disk encryption) by Apple for the macOS operating system
using a native Linux kernel API.
Cryptsetup supports only FileVault2 based on Core Storage and HFS+
filesystem (introduced in MacOS X 10.7 Lion). It does NOT support
the new version of FileVault based on the APFS filesystem used in
recent macOS versions.
Header formatting and FVAULT2 header changes are not supported;
cryptsetup never changes the FVAULT2 header on-device.
FVAULT2 extension requires the kernel userspace crypto API to be
available (for details, see the TCRYPT section) and a kernel
driver for the HFS+ (hfsplus) filesystem.
Cryptsetup should recognize the basic configuration for portable
drives.
The fvault2Dump command should work for all recognized FVAULT2
devices and doesn’t require superuser privilege.
For unlocking with the open, a password must be provided. Other
unlocking methods are not supported.
OPEN
open --type fvault2 <device> <name>
fvault2Open <device> <name> (old syntax)
Opens the FVAULT2 (a FileVault2-compatible) <device> (usually the
second partition on the device) and sets up a mapping <name>. See
cryptsetup-open(8).
Cryptsetup supports using native hardware encryption on drives
that provide an OPAL interface, both nested with dm-crypt and
standalone. Passphrases, tokens and metadata are stored using the
LUKS2 header format, and are thus compatible with any software or
system that uses LUKS2 (e.g., tokens).
OPAL support requires at least kernel v6.4. Resizing devices is
not supported.
The --hw-opal can be specified for OPAL + dm-crypt, and
--hw-opal-only can be specified to use OPAL only, without a
dm-crypt layer.
Opening, closing and enrolling tokens work the same way as with
LUKS2 and dm-crypt. The new parameters are only necessary when
formatting; the LUKS2 metadata will ensure the right setup is
performed when opening or closing.
If no subsystem label is specified, it will be automatically set
to HW-OPAL so that it is immediately apparent when a device uses
OPAL.
FORMAT
luksFormat --type luks2 --hw-opal <device> [<key file>]
Additionally specify --hw-opal-only instead of --hw-opal to avoid
the dm-crypt layer. Other than the usual passphrase, an admin
password will have to be specified when formatting the drive’s
first partition, and will have to be re-supplied when formatting
any other partition until a factory reset is performed.
ERASE
erase <device>
Securely erase a partition or device. Requires admin password.
Additionally specify --hw-opal-factory-reset for a FULL factory
reset of the drive, using the drive’s PSID (typically printed on
the label) instead of the admin password.
PSID must be entered without dashes, spaces or underscores.
WARNING: A factory reset will cause ALL data on the device to be
lost, regardless of the partition it is run on, if any, and
regardless of any LUKS2 header backup.
REPAIR
repair <device>
Tries to repair the device metadata if possible. Currently
supported only for LUKS device type. See cryptsetup-repair(8).
BENCHMARK
benchmark <options>
Benchmarks, ciphers and KDF (key derivation function). See
cryptsetup-benchmark(8).
Unless you understand the cryptographic background well, use LUKS.
With plain mode, there are a number of possible user errors that
massively decrease security. While LUKS cannot fix them all, it
can lessen the impact for many of them.
A lot of good information on the risks of using encrypted storage,
on handling problems and on security aspects can be found in the
Cryptsetup FAQ. Read it. Nonetheless, some risks deserve to be
mentioned here.
Backup: Storage media die. Encryption has no influence on that.
Backup is mandatory for encrypted data as well, if the data has
any worth. See the Cryptsetup FAQ for advice on how to back up an
encrypted volume.
Character encoding: If you enter a passphrase with special
symbols, the passphrase can change depending on character
encoding. Keyboard settings can also be changed, which can make
blind input hard or impossible. For example, switching from some
ASCII 8-bit variant to UTF-8 can lead to a different binary
encoding and hence a different passphrase seen by cryptsetup, even
if what you see on the terminal is exactly the same. It is
therefore highly recommended to select passphrase characters only
from 7-bit ASCII, as the encoding for 7-bit ASCII stays the same
for all ASCII variants and UTF-8.
LUKS header: If the header of a LUKS volume gets damaged, all data
is permanently lost unless you have a header backup. If a keyslot
is damaged, it can only be restored from a header backup or if
another active keyslot with a known passphrase is undamaged. This
risk is the result of a trade-off between security and safety, as
LUKS is designed for fast and secure wiping by just overwriting
the header and keyslot area.
Previously used partitions: If a partition was previously used, it
is a very good idea to wipe filesystem signatures, data, etc.,
before creating a LUKS or plain dm-crypt container. For a quick
removal of filesystem signatures, use wipefs(8) with the --all
option. Note that it does not remove data; it only invalidates
known format signatures. For a full wipe, overwrite the whole
partition before creating a container. If you do not know how to
do that, the cryptsetup FAQ describes several options.
Example 1: Create LUKS 2 container on block device /dev/sdX.
sudo cryptsetup --type luks2 luksFormat /dev/sdX
Example 2: Add an additional passphrase to keyslot 5.
sudo cryptsetup luksAddKey --key-slot 5 /dev/sdX
Example 3: Create LUKS header backup and save it to a file.
sudo cryptsetup luksHeaderBackup /dev/sdX --header-backup-file
/var/tmp/NameOfBackupFile
Example 4: Open LUKS container on /dev/sdX and map it to
sdX_crypt.
sudo cryptsetup open /dev/sdX sdX_crypt
WARNING: The command in example 5 will erase all keyslots.
You cannot use your LUKS container afterward anymore unless
you have a backup to restore.
Example 5: Erase all keyslots on /dev/sdX.
sudo cryptsetup erase /dev/sdX
Example 6: Restore LUKS header from backup file.
sudo cryptsetup luksHeaderRestore /dev/sdX
--header-backup-file /var/tmp/NameOfBackupFile
Cryptsetup returns 0 on success and a non-zero value on error.
Error codes are: 1 wrong parameters, 2 no permission (bad
passphrase), 3 out of memory, 4 wrong device specified, 5 device
already exists or device is busy.
Passphrase processing for PLAIN mode
Note that no iterated hashing or salting is done in plain mode. If
hashing is done, it is a single direct hash. This means that
low-entropy passphrases are easy to attack in plain mode.
From a terminal: The passphrase is read until the first newline,
i.e., '\n'. The input without the newline character is processed
with the default hash or the hash specified with --hash. The hash
result will be truncated to the key size of the used cipher, or
the size specified with -s.
From stdin: Reading will continue until a newline (or until the
maximum input size is reached), with the trailing newline
stripped. The maximum input size is defined by the same
compiled-in default as the maximum key file size and can be
overwritten using the --keyfile-size option.
The data read will be hashed with the default hash or the hash
specified with --hash. The hash result will be truncated to the
key size of the used cipher, or the size specified with -s.
Note that if --key-file=- is used for reading the key from stdin,
trailing newlines are not stripped from the input.
If "plain" is used as an argument to --hash, the input data will
not be hashed. Instead, it will be zero-padded (if shorter than
the key size) or truncated (if longer than the key size) and used
directly as the binary key. This is useful for directly specifying
a binary key. No warning will be given if the amount of data read
from stdin is less than the key size.
From a key file: It will be truncated to the key size of the used
cipher or the size given by -s and directly used as a binary key.
The --hash argument is being ignored. The --hash option is usable
only for stdin input in plain mode.
If the key file is shorter than the key, cryptsetup will quit with
an error. The maximum input size is defined by the same
compiled-in default as the maximum key file size and can be
overwritten using the --keyfile-size option.
Passphrase processing for LUKS
From a terminal: The passphrase is read until the first newline
and then processed by PBKDF2 without the newline character.
From stdin: LUKS will read passphrases from stdin up to the first
newline character or the compiled-in maximum key file length. If
--keyfile-size is given, it is ignored.
From key file: The complete keyfile is read up to the compiled-in
maximum size. Newline characters do not terminate the input. The
--keyfile-size option can be used to limit what is read.
LUKS uses Password-Based Key Derivation Function (PBKDF) to
protect against brute-force attacks and to give some protection to
low-entropy passphrases (see cryptsetup FAQ). LUKS1 supports the
PBKDF2 algorithm only, while LUKS2 also supports memory-hard
Argon2. PBKDFs are configured with costs: how long the iteration
should run (CPU cost or iteration count), how much memory is used
(memory cost), and how many parallel processes are used (parallel
cost). PBKDF2 supports only iteration count. Cryptsetup uses PBKDF
benchmarking to calculate optimal costs based on the computer
where the new passphrase is being initialized. If needed, these
costs can also be overwritten. Note that there are some hardcoded
limits, for details see MINIMAL AND MAXIMAL PBKDF COSTS section in
--pbkdf option description.
Whenever a passphrase is added to a LUKS header (luksAddKey,
luksFormat), the user may specify how much time the passphrase
processing should consume. The time is used to determine the
iteration count for PBKDF2, and higher times will offer better
protection for low-entropy passphrases, but the open command will
take longer to complete. For passphrases that have entropy higher
than the used key length, higher iteration times will not increase
security.
The default setting of one or two seconds is sufficient for most
practical cases. The only exception is a low-entropy passphrase
used on a device with a slow CPU, as this will result in a low
iteration count. On a slow device, it may be advisable to increase
the iteration time using the --iter-time option to obtain a higher
iteration count. This does slow down all later luksOpen operations
accordingly.
Incoherent behavior for invalid passphrases/keys
LUKS checks for a valid passphrase when a keyslot is decrypted.
The behavior of plain dm-crypt is different. It will always unlock
the device with the passphrase given. If the given passphrase is
wrong, the device mapped by plain dm-crypt will use the wrong
encryption key, and the data will be unreadable.
Supported ciphers, modes, hashes and key sizes
The available combinations of ciphers, modes, hashes and key sizes
depend on kernel support. See /proc/crypto for a list of available
options. You might need to load additional kernel crypto modules
to get more options.
Cryptsetup processes many operations outside of the kernel, so the
configured cryptographic library must also support selected
algorithms. Some algorithms may be missing as cryptsetup can be
compiled with various cryptographic backends (libraries).
Notes on passphrases
Mathematics can’t be bribed. Make sure you keep your passphrases
safe. There are a few nice tricks for constructing a fallback when
suddenly, out of the blue, your brain refuses to cooperate. These
fallbacks need LUKS, as it’s only possible with LUKS to have
multiple passphrases. Still, if your attacker model does not
prevent it, storing your passphrase in a sealed envelope somewhere
may be a good idea as well.
Notes on Random Number Generators
Random Number Generators (RNGs) used in cryptsetup are always the
kernel RNGs without any modifications or additions to the data
stream produced.
There are two types of randomness that cryptsetup/LUKS needs. One
type is used for salts, the AF splitter and for wiping deleted
keyslots. The second type is used for the volume key.
With recent kernels (Linux kernel 5.6), you do not need to worry
about selecting RNG (/dev/random or /dev/urandom). In a
low-entropy situation (embedded system), initialization of the
kernel RNG can take a very long time, but this happens before
cryptsetup can even be started. Use cryptsetup --help to show the
compiled-in default random number generator. See urandom(4) for
more information.
Authenticated disk encryption (EXPERIMENTAL)
Normal disk encryption modes are length-preserving (the plaintext
sector is the same size as a ciphertext sector) and can provide
only confidentiality protection, not cryptographically sound data
integrity protection.
Authenticated modes require additional space per-sector for the
authentication tag and use Authenticated Encryption with
Additional Data (AEAD) algorithms.
If you configure a LUKS2 device with data integrity protection,
there will be an underlying dm-integrity device, which provides
additional per-sector metadata space and data journal protection
to ensure atomicity of data and metadata updates. Because there
must be additional space for metadata and journal, the available
space for the device will be smaller than for length-preserving
modes.
The dm-crypt device then resides on top of such a dm-integrity
device. All activation and deactivation of this device stack is
performed by cryptsetup; there is no difference in using luksOpen
for integrity-protected devices. If you want to format a LUKS2
device with data integrity protection, use --integrity option (see
cryptsetup-luksFormat(8)).
Albeit Linux kernel 5.7 added TRIM support for standalone
dm-integrity devices, cryptsetup(8) can’t offer support for
discards (TRIM) in authenticated encryption mode, because the
underlying dm-crypt kernel module does not support this
functionality when dm-integrity is used as auth tag space
allocator (see --allow-discards in cryptsetup-open(8)).
Some integrity modes require two independent keys (a key for
encryption and authentication). Both these keys are stored in one
LUKS keyslot.
Support for authenticated modes is experimental, and only some
modes are available now. Note that very few authenticated
encryption algorithms are suitable for disk encryption. You also
cannot use CRC32 or other non-cryptographic checksums (other than
the special integrity mode "none"). If, for some reason, you want
to have integrity control without using authentication mode, then
you should separately configure dm-integrity independently of
LUKS2.
Notes on loopback device use
Cryptsetup is usually used directly on a block device (disk
partition or LVM volume). However, if the device argument is a
file, cryptsetup tries to allocate a loopback device and map it
into this file. Of course, you can always map a file to a loop
device manually. See the cryptsetup FAQ for an example.
When device mapping is active, you can see the loop backing file
in the status command output. Also see losetup(8).
LUKS2 header locking
The LUKS2 on-disk metadata is updated in several steps, and to
achieve a proper atomic update, there is a locking mechanism. For
an image in a file, the code uses the flock(2) system call. For a
block device, lock is performed over a special file stored in a
locking directory (by default /run/cryptsetup). The locking
directory should be created with the proper security context by
the distribution during the boot-up phase. Only LUKS2 uses locks;
other formats do not use this mechanism.
LUKS on-disk format specification
For LUKS on-disk metadata specification, see LUKS1
<https://gitlab.com/cryptsetup/cryptsetup/wikis/Specification> and
LUKS2 <https://gitlab.com/cryptsetup/LUKS2-docs>.
Cryptsetup was originally written by Jana Saout <jana@saout.de>.
The LUKS extensions and original man page were written by Clemens
Fruhwirth <clemens@endorphin.org>. Man page extensions by Milan
Broz <gmazyland@gmail.com>. Man page rewrite and extension by Arno
Wagner <arno@wagner.name>.
Report bugs at cryptsetup mailing list
<cryptsetup@lists.linux.dev> or in Issues project section
<https://gitlab.com/cryptsetup/cryptsetup/-/issues/new>.
Please attach the output of the failed command with --debug option
added.
Cryptsetup FAQ
<https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions>
cryptsetup(8), integritysetup(8) and veritysetup(8)
Part of cryptsetup project
<https://gitlab.com/cryptsetup/cryptsetup/>. This page is part of
the Cryptsetup ((open-source disk encryption)) project.
Information about the project can be found at
⟨https://gitlab.com/cryptsetup/cryptsetup⟩. If you have a bug
report for this manual page, send it to dm-crypt@saout.de. This
page was obtained from the project's upstream Git repository
⟨https://gitlab.com/cryptsetup/cryptsetup.git⟩ on 2025-08-11. (At
that time, the date of the most recent commit that was found in
the repository was 2025-08-01.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
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cryptsetup 2.8.1-git 2025-08-09 CRYPTSETUP(8)
Pages that refer to this page: homectl(1), systemd-cryptenroll(1), crypttab(5), cryptsetup(8), cryptsetup-benchmark(8), cryptsetup-bitlkDump(8), cryptsetup-close(8), cryptsetup-config(8), cryptsetup-convert(8), cryptsetup-erase(8), cryptsetup-fvault2Dump(8), cryptsetup-isLuks(8), cryptsetup-luksAddKey(8), cryptsetup-luksChangeKey(8), cryptsetup-luksConvertKey(8), cryptsetup-luksDump(8), cryptsetup-luksFormat(8), cryptsetup-luksHeaderBackup(8), cryptsetup-luksHeaderRestore(8), cryptsetup-luksKillSlot(8), cryptsetup-luksRemoveKey(8), cryptsetup-luksResume(8), cryptsetup-luksSuspend(8), cryptsetup-luksUUID(8), cryptsetup-open(8), cryptsetup-reencrypt(8), cryptsetup-refresh(8), cryptsetup-repair(8), cryptsetup-resize(8), cryptsetup-ssh(8), cryptsetup-status(8), cryptsetup-tcryptDump(8), cryptsetup-token(8), fsadm(8), integritysetup(8), losetup(8), systemd-cryptsetup(8), systemd-cryptsetup-generator(8), systemd-gpt-auto-generator(8), systemd-makefs@.service(8), veritysetup(8)
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