NAME
cryptsetup-benchmark - benchmarks ciphers and KDFSYNOPSIS
cryptsetup benchmark [<options>]DESCRIPTION
Benchmarks ciphers and KDF (key derivation function). Without parameters, it tries to measure few common configurations.OPTIONS
--hash, -h <hash-spec>The specified hash is used for PBKDF2 and AF
splitter.
Set the cipher specification string.
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.
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).
The number of milliseconds to spend with PBKDF
passphrase processing. Specifying 0 as parameter selects the compiled-in
default.
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.
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.
Suppresses all confirmation questions. Use
with care!
If the --verify-passphrase option is not specified, this option also switches
off the passphrase verification.
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.
Show the program version.
Show short option help.
Show help text and default parameters.
REPORTING BUGS
Report bugs at cryptsetup <[email protected]>mailing or in Issues project section <https://gitlab.com/cryptsetup/cryptsetup/-/issues/new>.SEE ALSO
Cryptsetup FAQ <https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions>CRYPTSETUP
Part of cryptsetup project <https://gitlab.com/cryptsetup/cryptsetup/>.2023-12-18 | cryptsetup 2.6.1 |