On Fri, May 03, 2019 at 10:32:19PM +0200, David Kozub wrote:
On Wed, 1 May 2019, Christoph Hellwig wrote:
I successfully tested toggling the MBR done flag and writing the shadow MBR
using some tools I hacked together with a Samsung SSD 850 EVO drive.
Can you submit the tool to util-linux so that we get it into distros?
There is already Scott's sed-opal-temp and a fork by Jonas that adds
support for older version of these new IOCTLs. There was already some
discussion of getting that to util-linux.
While I like my hack, sed-opal-temp can do much more (my tool supports just
the few things I actually use). But there are two things which sed-opal-temp
currently lacks which my hack has:
* It can use a PBKDF2 hash (salted by disk serial number) of the password
rather than the password directly. This makes it compatible with sedutil
and I think it's also better practice (as firmware can contain many
* It contains a 'PBA' (pre-boot authorization) tool. A tool intended to be
run from shadow mbr that asks for a password and uses it to unlock all
disks and set shadow mbr done flag, so after restart the computer boots
into the real OS.
@Scott: What are your plans with sed-opal-temp? If you want I can update
Jonas' patches to the adapted IOCTLs. What are your thoughts on PW hashing
and a PBA tool?
I will accept any and all patches to sed opal tooling, I am not picky. I will
also give up maintainership of it is someone else feels they can (rightfully
so) do a better job.
Jon sent me a patch for the tool that will deal with writing to the shadow MBR,
so once we know these patches are going in i'll pull that patch into the tool.
Then I guess that leaves PBKDF2 which I don't think will be too hard to pull in.
With regard to your PBA tool, is that actually being run post-uefi/pre-linux?
IE are we writing your tool into the SMBR and that's what is being run on bootup?
Jon, if you think it's a good idea can you ask David if Revanth or you wants
to take over the tooling? Or if anyone else here wants to own it then let me know.