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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | REPORTING BUGS | SEE ALSO | CRYPTSETUP |
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CRYPTSETUP-BENCHMARK(8) Maintenance Commands CRYPTSETUP-BENCHMARK(8)
cryptsetup-benchmark - benchmarks ciphers and KDF
cryptsetup benchmark [<options>]
Benchmarks ciphers and KDF (key derivation function). Without
parameters, it tries to measure few common configurations.
To benchmark other ciphers or modes, you need to specify --cipher
and --key-size options.
To benchmark PBKDF you need to specify --pbkdf or --hash with
optional cost parameters --iter-time, --pbkdf-memory or
--pbkdf-parallel.
NOTE: This benchmark uses memory only and is only informative.
You cannot directly predict real storage encryption speed from
it.
For testing block ciphers, this benchmark requires kernel
userspace crypto API to be available (introduced in Linux kernel
2.6.38). If you are configuring kernel yourself, enable
"User-space interface for symmetric key cipher algorithms" in
"Cryptographic API" section (CRYPTO_USER_API_SKCIPHER .config
option).
<options> can be [--cipher, --key-size, --hash, --pbkdf,
--iter-time, --pbkdf-memory, --pbkdf-parallel].
--hash, -h <hash-spec>
The specified hash is used for PBKDF2 and AF splitter.
--cipher, -c <cipher-spec>
Set the cipher specification string.
--key-size, -s bits
Sets key size in bits. The argument has to be a multiple of
8. The possible key-sizes are limited by the cipher and mode
used.
See /proc/crypto for more information. Note that key-size in
/proc/crypto is stated in bytes.
This option can be used for open --type plain or luksFormat.
All other LUKS actions will use the key-size specified in the
LUKS header. Use cryptsetup --help to show the compiled-in
defaults.
--pbkdf <PBKDF spec>
Set Password-Based Key Derivation Function (PBKDF) algorithm
for LUKS keyslot. The PBKDF can be: pbkdf2 (for PBKDF2
according to RFC2898), argon2i for Argon2i or argon2id for
Argon2id (see Argon2
<https://www.cryptolux.org/index.php/Argon2> for more info).
For LUKS1, only PBKDF2 is accepted (no need to use this
option). The default PBKDF for LUKS2 is set during
compilation time and is available in cryptsetup --help
output.
A PBKDF is used for increasing dictionary and brute-force
attack cost for keyslot passwords. The parameters can be
time, memory and parallel cost.
For PBKDF2, only time cost (number of iterations) applies.
For Argon2i/id, there is also memory cost (memory required
during the process of key derivation) and parallel cost
(number of threads that run in parallel during the key
derivation.
Note that increasing memory cost also increases time, so the
final parameter values are measured by a benchmark. The
benchmark tries to find iteration time (--iter-time) with
required memory cost --pbkdf-memory. If it is not possible,
the memory cost is decreased as well. The parallel cost
--pbkdf-parallel is constant and is checked against available
CPU cores.
You can see all PBKDF parameters for particular LUKS2 keyslot
with cryptsetup-luksDump(8) command.
NOTE: If you do not want to use benchmark and want to specify
all parameters directly, use --pbkdf-force-iterations with
--pbkdf-memory and --pbkdf-parallel. This will override the
values without benchmarking. Note it can cause extremely long
unlocking time. Use only in specific cases, for example, if
you know that the formatted device will be used on some small
embedded system.
MINIMAL AND MAXIMAL PBKDF COSTS: For PBKDF2, the minimum
iteration count is 1000 and maximum is 4294967295 (maximum
for 32bit unsigned integer). Memory and parallel costs are
unused for PBKDF2. For Argon2i and Argon2id, minimum
iteration count (CPU cost) is 4 and maximum is 4294967295
(maximum for 32bit unsigned integer). Minimum memory cost is
32 KiB and maximum is 4 GiB. (Limited by addressable memory
on some CPU platforms.) If the memory cost parameter is
benchmarked (not specified by a parameter) it is always in
range from 64 MiB to 1 GiB. The parallel cost minimum is 1
and maximum 4 (if enough CPUs cores are available, otherwise
it is decreased).
--iter-time, -i <number of milliseconds>
The number of milliseconds to spend with PBKDF passphrase
processing. Specifying 0 as parameter selects the compiled-in
default.
--pbkdf-memory <number>
Set the memory cost for PBKDF (for Argon2i/id the number
represents kilobytes). Note that it is maximal value, PBKDF
benchmark or available physical memory can decrease it. This
option is not available for PBKDF2.
--pbkdf-parallel <number>
Set the parallel cost for PBKDF (number of threads, up to 4).
Note that it is maximal value, it is decreased automatically
if CPU online count is lower. This option is not available
for PBKDF2.
--batch-mode, -q
Suppresses all confirmation questions. Use with care!
If the --verify-passphrase option is not specified, this
option also switches off the passphrase verification.
--debug or --debug-json
Run in debug mode with full diagnostic logs. Debug output
lines are always prefixed by #.
If --debug-json is used, additional LUKS2 JSON data
structures are printed.
--version, -V
Show the program version.
--usage
Show short option help.
--help, -?
Show help text and default parameters.
Report bugs at cryptsetup mailing list
<cryptsetup@lists.linux.dev> or in Issues project section
<https://gitlab.com/cryptsetup/cryptsetup/-/issues/new>.
Please attach 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 2023-12-22. (At
that time, the date of the most recent commit that was found in
the repository was 2023-12-20.) 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
(which is not part of the original manual page), send a mail to
man-pages@man7.org
cryptsetup 2.6.1-git 2022-12-14 CRYPTSETUP-BENCHMARK(8)
Pages that refer to this page: cryptsetup(8)
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HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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