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From:   Gabriel C <nix.or.die@gmail.com>
Date:   Mon, 16 Apr 2018 00:35:33 +0200
Message-ID: <CAEJqkghu-c90=cocnkxW7zD9twkb0v=DTNbQgmUC4JGC6fvgWw@mail.gmail.com>
Subject: Re: [RFC] Passing luks passphrase from grub to systemd
To:     Hansjoerg Lipp <hjlipp@web.de>
Cc:     LKML <linux-kernel@vger.kernel.org>
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2018-04-15 21:06 GMT+02:00 Hansjoerg Lipp <hjlipp@web.de>:
> Hello,
>

Hello,

> as I'm stuck with a (non-EFI x86_64) system with encrypted root
> partition, I have to enter the passphrase twice (grub needs it for
> getting the kernel etc., systemd needs it for mounting the root
> partition). This can be quite inconvenient, especially if the passphrase
> is long and contains special characters, and grub assumes a different
> keyboard layout.
> I therefore developed a proof of concept code allowing grub to pass the
> passphrase to the kernel and systemd to get the passphrase from the
> kernel. See the description and patch for the Linux part and the link to
> all changes below.
>
> I'm presenting my code here because I'd like to know if something like
> this might be useful also for other people (and further development
> might be sensible). I'd also be thankful for comments how this might be
> implemented in a better way.

Somethng like this is not needed.
All that is possible already from userspace.

Systemd can do that on his own ( see systemd-cryptsetup-generator )
( other init ofc too ) assuming your initrd , cryptsetup and grub is
setup correctly.


Regards,

Gabriel C