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Message-ID: <1518635157.4749.50.camel@profitbricks.com>
Subject: Re: Read-protected UEFI variables
From:   Benjamin Drung <benjamin.drung@profitbricks.com>
To:     =?ISO-8859-1?Q?M=F4she?= van der Sterre <me@moshe.nl>
Cc:     Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        linux-efi@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Date:   Wed, 14 Feb 2018 20:05:57 +0100
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Am Mittwoch, den 14.02.2018, 19:18 +0100 schrieb Môshe van der Sterre:
> On 02/14/2018 02:21 PM, Benjamin Drung wrote:
> > If the UEFI is as secure as storing an unencrypted file on a hard
> > drive, I am satisfied. Or do you have a better idea where to store
> > the
> > SSH keys for a diskless system that boots via network?
> 
> I assume it would be best to use TPM for this (if your systems have
> TPM chips), it is designed for use-cases like this. Searching for
> "tpm ssh keys" gives a decent amount of results. Mostly targeted at
> user keys instead of server keys, so this might need some tinkering
> to get working.

I check our systems. They just have TPM headers, but no TPM chips
according to the user manual. The directory /sys/class/tpm/ is either
empty or not existing. Adding TPM chips to all servers is no too
expensive (to much man power required). So sadly, this is no option for
us.

-- 
Benjamin Drung
System Developer
Debian & Ubuntu Developer

ProfitBricks GmbH
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