Changed the checking of required hashes or required rollback state
to be right before boot, allowing the user to sign/set defaults
in interactive mode.
Also cleaned up usages of recovery and fixed iso parameter
regression.
Similar to qubes-update, it will save then verify the hashes of
the kexec files. Once TOTP is verified, a normal boot will verify
that the file hashes and all the kexec params match and if
successful, boot directly to OS.
Also added a config option to require hash verification for
non-recovery boots, failing to recovery not met.
This adds support for seamless booting of Qubes with a TPM disk key,
as well as signing of qubes files in /boot with a Yubikey.
The signed hashes also includes a TPM counter, which is incremented
when new hashes are signed. This prevents rollback attacks against
the /boot filesystem.
The TPMTOTP value is presented to the user at the time of entering
the disk encryption keys. Hitting enter will generate a new code.
The LUKS headers are included in the TPM sealing of the disk
encryption keys.
