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Date: Tue, 19 May 2015 13:55:10 -0400
From: "Theodore Ts'o" <tytso@mit.edu>
To: David Howells <dhowells@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>, Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Borislav Petkov <bp@alien8.de>, Jiri Kosina <jkosina@suse.cz>
Subject: Re: Should we automatically generate a module signing key at all?
Message-ID: <20150519175510.GB26822@thunk.org>
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On Tue, May 19, 2015 at 05:23:19PM +0100, David Howells wrote:
> Did you mean make it possible to only use external hardware for storing the
> key?  That wouldn't very convenient for building our kernels in our build farm
> - we have a lot of machines and all of them would have to be equiped with the
> key.  Besides, we *want* to discard the private key where possible as soon as
> possible because then we can't leak it and we can't be forced to disclose it.

Oh, so you are generating a one-time key for each kernel build, and
then dropping the public key into a cert which is then signed by some
trusted CA system?  (Which I presume *would* be done with the private
key stored in some trusted secured hardware --- i.e., YubiKey,
SmartCard, or some other tempest-shielded hardware designed for use by
CA's)?

						- Ted
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