By changing encryption sector size during reencryption we may
increase effective logical block size for dm-crypt active device.
For example if hosted filesystem on encrypted data device
has block size set to 512 bytes and we increase dm-crypt logical
size durign reencryption to 4096 bytes it breaks the filesystem.
Do not allow encryption sector size to be increased over value
provided by fs superblock in BLOCK_SIZE property.
The check is applied while initialising LUKS2 device encryption
(reencrypt --encrypt/--new) or when initialising LUKS2 reencryption
on active dm-crypt device.
Note that this check cannot be applied on offline device (data device
is encrypted).
We should abort LUKS device in-place encryption
when target data device or metadata device
contain broken LUKS metadata (any version).
Filed crypt_load() call was not good enough check
because the call fails also when a device contains
LUKS metadata overlapping with other superblock
(e.g. LVM2 PV signature).
Let blkid decide if device contains broken LUKS
metadata or not.
Fixes: #723.
Do not resume reencryption operation with conflicting parameters.
For example if operation was initialized as --encrypt do not
allow resume with oposing parameter --decrypt and vice versa.
Also checks for conflicting --resilience parameters (datashift cannot
be changed after initialization).
Previously, conflicting reencryption parameters were silently ignored.
So, for example operation initialized with mode --encrypt and resumed
with mode --decrypt simply finished --encrypt operation and did not
report any error. This could lead to impresion different type of
operation was perfomed instead.
Fixes: #570.
If auto-detection fails for other reason just return the
error. Users may now bypass active device auto-detection
with --force-offline-reencrypt option.
It can be used to enforce offline reencryption
in batch mode when data_device is regular file
and therefore cryptsetup cannot detect properly
active device dm name.
Also it may be useful when active device
auto-detection fails for some reason and user
has no other choice but inspect device holders
manually.
