The crypt_set_data_offset sets the data offset for LUKS and LUKS2 devices
to specified value in 512-byte sectors.
This value should replace alignment calculation in LUKS param structures.
All previous version of cryptsetup wiped only first 4k for LUKS1
and both JSON areas for LUKS2 (first 32k) and the allocated
keyslot area (as it contained the generated key).
Remaining areas (unused keyslots, padding, and alignment) were
not wiped and could contain some previous data.
Since this commit, the whole area up to the data offset is zeroed,
and subsequently, all keyslots areas are wiped with random data.
Only exceptions are
- padding/alignment areas for detached header
if the data offset is set to 0
- bogus LUKS1 keyslot areas (upstream code never
created such keyslots but someone could use that).
This operation could slow down luksFormat on some devices, but
it guarantees that after this operation LUKS header does not
contain any foreign data.
Move all messages to cryptsetup tools and print these
verbose messages:
- Key slot X unlocked.
- Key slot X created.
- Key slot X removed.
and
- Token X created.
- Token X removed.
Also print error, if unknown token is tried to be removed.
Almost all the headers in cryptsetup are self-suffienct (in that they
compile on their own). By including <stddef.h>, <stdint.h>, or
<sys/types.h>, all headers will now compile on their own.
This is useful for importing cryptsetup into Bazel/Blaze.
Some ciphers and key sizes created on-disk metadata that cannot be used.
Use the same test for length-preserving cipher as LUKS1.
Also check if key for integrity algorithm is not too small.
Fixes#373.
For some strange filesystems (nfs) we get big block size (1MB).
For temporary keyslot devices this mapping does not make sense and
can cause problem with detached headers that are smaller (contains
exactly the slot size).
This patch adds support for using keyring for volume key
and support for new integrity fields for dm-crypt.
Also helpers for searching disk by id.
To be used later.
Also cache its value in active context, so we run benchmark
only once.
The patch also changes calculated value for LUKS1 key digest
to 125 miliseconds (it means that for full 8 used slots
the additional slow-down is circa 1 second).
Note that there is no need to have too high iteration count
for key digest; if it is too computationally expensive, attacker
will better decrypt of one sector with candidate key anyway.
(Check for a known signature.)
The reason to have some delay for key digest check was
to complicate brute-force search for volume key with LUKS header
only (and if RNG used to generate volumekey was flawed
allowing such a search i reasonable time).
Prepare API for PBKDF that can set three costs
- time (similar to iterations in PBKDF2)
- memory (required memory for memory-hard function)
- threads (required number of threads/CPUs).
This patch also removes wrongly designed API call
crypt_benchmark_kdf and replaces it with the new call
crypt_benchmark_pbkdf.
Two functions for PBKDF per context setting
are introduced: crypt_set_pbkdf_type and crypt_get_pbkdf_type.
The patch should be backward compatible when using
crypt_set_iteration_time function (works only for PBKDF2).
Signed-off-by: Milan Broz <gmazyland@gmail.com>
The Argon2i/id is a password hashing function that
won Password Hashing Competiton.
It will be (optionally) used in LUKS2 for passworrd-based
key derivation.
We have to bundle code for now (similar PBKDF2 years ago)
because there is yet no usable implementation in common
crypto libraries.
(Once there is native implementation, cryptsetup
will switch to the crypto library version.)
For now, we use reference (not optimized but portable) implementation.
This patch contains bundled Argon2 algorithm library copied from
https://github.com/P-H-C/phc-winner-argon2
For more info see Password Hashing Competition site:
https://password-hashing.net/
and draft of RFC document
https://datatracker.ietf.org/doc/draft-irtf-cfrg-argon2/
Signed-off-by: Milan Broz <gmazyland@gmail.com>
this patches improves two areas:
1) it checks for keyslot areas overlaping each other
2) it checks if all keyslot areas fit in header area of device
(pre-data-offset area) or if it can fit file (detached header)
it's being loaded from. Those new checks are based on real data
found in header (offsets) rather than based on assumption calculated
from key length
alter all checks for devfd value after device_open to
less than zero insted of equals to -1. device_open will
return values different from -1 in case error happens.
In LUKSv1 device_open should always return -1 in case of
error but this check is safer.
The rest is just formating improvement.
fix double close() cases in LUKS_hdr_backup() and LUKS_hdr_restore()
functions. It should be harmless unless libcryptsetup is used
in multi-thread setup which is not supported anyway.
- ensure that strings are \0 terminated (most of this is already
handled on higher level anyway)
- fix resource leak in error path in tcrypt.c
- fix time of check/time of use race in sysfs path processing
- insruct Coverity scanner to ignore constant expression in random.c
(it is intented to stop compile-time misconfiguration of RNG that would be fatal)
