Re: MODSIGN without RTC?

From: Alexander Holler
Date: Tue Feb 12 2013 - 08:08:45 EST


Am 11.02.2013 20:44, schrieb Alexander Holler:
Am 07.02.2013 19:44, schrieb Olaf Titz:
Another option would be to make a configure option to just ignore the
date. I'm not sure if I would like to use MODSIGN when I have to fear
that the machine wouldn't start when the RTC fails or got set to a wrong
date.

Or just ignore the date unconditionally. After all, when a certificate
check fails due to out-of-validity-period, then you can always "fix"
that by appropriately setting the clock. So for security, in this
application, the date check is outright useless.

I don't think that is an option, because the date check is part of the
crypto-api and not a part of the modsign-stuff.

So it's necessary that the crypto-api offers a flag to ignore the dates
and another flag to mark such keys as invalid because of the date. The
first flag is necessary to load and use the keys, the second flag for
(maybe) other users of the crypto-api which might not use such invalid
keys.

Another option would be, to just load every key, regardless of the dates of the keys, and let the user of the keys (e.g. modsign) decide if they accept the dates in the keys.

But I'm missing the big picture about the crypto-api and their users, therefor I better don't touch that part of the kernel myself. ;)

Regards,

Alexander
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