It is called from kernel crypt backend unconditionally with
the proper define in config.h but some static parrsers are not so clever.
Compilation will fail in linker phase anyway if wrongly used.
The routine was originaly used in code for resetting default
argument values. It was used in cli plugins related code
where we needed to parse command line arguments twice.
This fixes multiple issues found by coverity in the startup key
code and also makes the parsing less complicated -- we don't need
to loop through all metadata entries in the BEK file if we are
expecting only one metadata entry of a specific type.
These are false positives and gcc internal detection of this
pattern seems to be broken again.
In this path we must avoid memcpy the whole buffer, it can contain
some bytes after null char, so use MIN/strlen here.
Provides example of loadable token handler for activation
json validation and metadata dump.
For creating new ssh example token use special cryptsetup-ssh
binary.
Add API call that can directly print JSON metadata area from LUKS2 device.
For commandline it also adds --dump-json-metadata option for luksDump action.
Note that the binary metadata (UUID, version etc) is not part of this output.
(We reserve flags parameter to be able to add this later.)
Fixes: #511
The code expects that change key is done in-place if there is not
a free space in keyslot area for safe key swap.
This patch makes the code behaves the same as in LUKS1,
luksChangeKey now works the same.
With JSON, we can actually retain the slot number in all cases
(except user intentionally set new slot #).
This patch changes the crypt_keyslot_change_by_passphrase() API
call to retain keyslot number for LUKS2.
Fixes: #464
We cannot trust possibly broken keyslots metadata here through LUKS_keyslots_offset().
Expect first keyslot is aligned, if not, then manual repair is neccessary.
(This situation happen if partition table signarture overwrites slot 4 area).
Also, if keyslot order is different, current repair code does not work properly
(this can happen only with downconverting LUKS2 device).
This patch adds support for Linux kernel (since version 5.11) dm-integrity
fixes that disables integrity recalculation if keyed algorithms (HMAC) is used.
Original dm-integrity superblock version <=4 is recalculation offset
field not protected by HMAC. An attacker can move this pointer and force
the kernel to recalculate the data area, ignoring original HMAC tags.
N.B. dm-integrity was not intended to protect against intentional changes.
Better use authenticated encryption (AEAD) in combination with dm-crypt.
It is designed to protect against random data corruption caused by hardware
or storage medium faults.
Despite that, we try to keep the system secure if keyed algorithms are used.
There are two possible keyed algorithms in dm-integrity - algorithm used
to protect journal and superblock (--journal-integrity) and algorithms
for protecting data (--integrity).
The dm-integrity superblock is guarded by --journal-integrity, so if you want
to protect data with HMAC, you should always also use HMAC for --journal-integrity.
The keys are independent. If HMAC is used for data but not for the journal,
recalculation is disabled by default.
For new kernel dm-integrity, the HMAC option also uses salt in superblock
to avoid an easy way to distinguish that the HMAC key is the same for two devices
(if data are the same).
The new HMAC and superblock are enabled automatically if the kernel supports it
(you can see superblock version 5 and fix_hmac flag in dump command).
If you need to use (insecure) backward compatibility, then two new integritysetup
options are introduced:
Use --integrity-legacy-recalc (instead of --integrity-recalc) to allow recalculation
on legacy devices.
Use --integrity-legacy-hmac in format action to force old insecure version
format (with HMAC).
Libcryptsetup API also introduces flags
CRYPT_COMPAT_LEGACY_INTEGRITY_HMAC and
CRYPT_COMPAT_LEGACY_INTEGRITY_RECALC
to set these through crypt_set_compatibility() call.
The crypt_activate_by_pin_token may be used only from new
dynamicly loadable token plugins.
Also refactors code for dynamically loadable plugins so
that it does not use crypt_token_handler structure anymore.
Old structure remains used only in crypt_token_register call.
This reverts mostly these commits:
42692418c2a985c12659
The library was ment to export common functions shared by
all cryptsetup tools and planned LUKS2 tokens plugins.
It is no longer needed.
THis fixes a problem for TCRYPT and reencryption in scripts
where "Nothing to read on input." is displayed because
cryptsetup retries password query even in stdin mode.
LUKS2 decryption is currently not supported for devices
with LUKS2 metadata placed in head of data devices. The decryption
still works correctly, but resulting plaintext device has data on
unexpected (original) offset. For example at offset of 16MiB in case
of default LUKS2 header.
Fixes: #614.
crypt_header_is_detached checks if initialized LUKS context uses detached header
(LUKS header located on a different device than data.)
This is a runtime attribute, it does not say if a LUKS device requires detached header.