Optionally, embedd PKCS#11 token URI and encrypted key in LUKS2 JSON
metadata header. That way it becomes very easy to unlock properly set up
PKCS#11-enabled LUKS2 volumes, a simple /etc/crypttab line like the
following suffices:
mytest /dev/disk/by-partuuid/41c1df55-e628-4dbb-8492-bc69d81e172e - pkcs11-uri=auto
Such a line declares that unlocking via PKCS#11 shall be attempted, and
the token URI and the encrypted key shall be read from the LUKS2 header.
An external key file for the encrypted PKCS#11 key is hence no longer
necessary, nor is specifying the precise URI to use.
Let's make libcryptsetup a dlopen() style dep for PID 1 (i.e. for
RootImage= and stuff), systemd-growfs and systemd-repart. (But leave to
be a regulra dep in systemd-cryptsetup, systemd-veritysetup and
systemd-homed since for them the libcryptsetup support is not auxiliary
but pretty much at the core of what they do.)
This should be useful for container images that want systemd in the
payload but don't care for the cryptsetup logic since dm-crypt and stuff
isn't available in containers anyway.
Fixes: #8249
"crypt-util.c" is such a generic name, let's avoid that, in particular
as libc's/libcrypt's crypt() function is so generically named too that
one might thing this is about that. Let's hence be more precise, and
make clear that this is about cryptsetup, and nothing else.
We already had cryptsetup-util.[ch] in src/cryptsetup/ doing keyfile
management. To avoid the needless confusion, let's rename that file to
cryptsetup-keyfile.[ch].