A keyslot not bound to any segment can store any key for any purpose.
To easily check slot status, new enum value is introduced.
This status is valid only for LUKS2, so the functions are backward compatible
with LUKS1.
We can't wipe (overwrite with random noise) wrapped key in
kernel. Such keys are usually structured and not only random
bytes.
Also it doesn't make sense to wipe these keys. They are supposed
to be protected (encrypted) by keys sealed in hardware.
TODO: tests: 1) with header, 2) without header (dm-crypt only),
3) arch with working paes cipher (at least).
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.
Move all keyring functions to one place and separate LUKS2 specific
code to generic handling.
Also fix possible mismatch if volume key is in keyring but it is not native
LUKS2 device (libarary cannot process such a device properly).
This fixes crypt_keyslot_add_by_key where we were unable to store
keyslot (unbound to segment) with different key_size.
The code used (new) volume key size implicitly which could be wrong
if new size was not compatible with cipher parameter for keyslot area.
For now, crypto API quietly used cipher witout IV if a cipher
algorithm wihtou IV specificaton was used (e.g. aes-xts).
This caused fail later during activation.
This patch allows only two specific backed use without specified IV
(ECB mode and NULL cipher).
Also check cipher string early during parsing of CLI options.
When loading first dm-crypt table (or action that triggers dm-crypt
module load) we do not know dm-crypt version yet. Let's assume all
kernels before 4.15.0 are flawed and reject VK load via kernel keyring
service.
When dm-crypt is already in kernel, check for correct target version
instead (v1.18.1 or later).
The keyfile interface was designed, well, for keyfiles.
Unfortunately, a keyfile can be placed on a device and the size_t offset
can overflow.
We have to introduce new set of fucntions that allows 64bit offsets even on 32bit systems:
- crypt_resume_by_keyfile_device_offset
- crypt_keyslot_add_by_keyfile_device_offset
- crypt_activate_by_keyfile_device_offset
- crypt_keyfile_device_read
The new functions have added _device_ in name.
Old functions are just internall wrappers around these.
Also cryptsetup --keyfile-offset and --new-keyfile-offset must now
process 64bit offsets.
For more info see issue 359.
Reduce bloated code in low level keyring utilities code.
Move log messages higher the library code.
Also return -ENOTSUP when code was compiled out by configure
option.
Remove code for handling multiple digests per single keyslot.
Same would apply to segments with the only exception of segment
in-reencryption. We need that exception so that we will not lose
old key digests too early.
Originally the key description for VK was derived
from segment id. This could lead to ambiguity when
keyslot key is verified and loaded in kernel keyring
using activation functions with CRYPT_ACTIVATE_KEYRING_KEY
flag raised.
crypt_deactivate_* fail earlier without noisy dm retries
when other device holders detected. The early detection
works if:
a) other device-mapper device has a hold reference on the
device
- or -
b) mounted fs is detected on the device
Any deactivation flag CRYPT_DEACTIVATE_FORCE or
CRYPT_DEACTIVATE_DEFERRED will disable this detection
before this patch any LUKS2 requirement defined in header
would stop a restricted operation from proceeding further.
This patch adds ability to mask requirements (internal only).
