From: "Theodore Ts'o" <tytso@mit.edu>
To: "Jörn Engel" <joern@logfs.org>
Cc: Andy Lutomirski <luto@amacapital.net>,
Jeff Garzik <jgarzik@pobox.com>,
David Safford <safford@us.ibm.com>,
"H. Peter Anvin" <hpa@zytor.com>,
Leonidas Da Silva Barbosa <leosilva@linux.vnet.ibm.com>,
Ashley Lai <ashley@ashleylai.com>,
Rajiv Andrade <mail@srajiv.net>,
Marcel Selhorst <tpmdd@selhorst.net>,
Sirrix AG <tpmdd@sirrix.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Kent Yoder <key@linux.vnet.ibm.com>,
David Safford <safford@watson.ibm.com>,
Mimi Zohar <zohar@us.ibm.com>,
"Johnston, DJ" <dj.johnston@intel.com>
Subject: Re: TPMs and random numbers
Date: Thu, 12 Sep 2013 22:13:49 -0400 [thread overview]
Message-ID: <20130913021349.GB9445@thunk.org> (raw)
In-Reply-To: <20130912222309.GH3809@logfs.org>
On Thu, Sep 12, 2013 at 06:23:09PM -0400, Jörn Engel wrote:
> It is worse in three ways:
> - it costs performance,
> - it may create a false sense of safety and
> - it actively does harm if we credit it as entropy.
>
> How much weight you assign to each of those is up to you. So long as
> we don't credit any of it as entropy, I am not too adverse to mixing
> it in. But I can equally see benefit in burning the bridges.
Well, mixing it in and using /dev/[u]random is certainly better than
blindly using the output from the RNG from the TPM directly as a
key.
I'm not sure what you mean by "burning the bridges"; what is the
alternative that you are suggesting?
- Ted
next prev parent reply other threads:[~2013-09-13 2:14 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-11 17:22 David Safford
2013-09-11 17:49 ` Andy Lutomirski
2013-09-11 18:45 ` Theodore Ts'o
2013-09-11 19:06 ` Jeff Garzik
2013-09-11 19:08 ` Andy Lutomirski
2013-09-11 19:25 ` H. Peter Anvin
2013-09-11 20:28 ` Theodore Ts'o
2013-09-11 20:44 ` H. Peter Anvin
2013-09-11 18:47 ` David Safford
2013-09-12 21:57 ` Jörn Engel
2013-09-12 23:38 ` Andy Lutomirski
2013-09-12 23:39 ` Jeff Garzik
2013-09-12 22:13 ` Jörn Engel
2013-09-12 23:51 ` Andy Lutomirski
2013-09-12 22:23 ` Jörn Engel
2013-09-13 2:13 ` Theodore Ts'o [this message]
2013-09-13 2:22 ` Jörn Engel
2013-09-11 22:08 ` Johnston, DJ
-- strict thread matches above, loose matches on Subject: below --
2013-09-09 21:11 H. Peter Anvin
2013-09-11 1:50 ` Andy Lutomirski
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