Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 20 Mar 2016 15:25:23 -0400
From:      Eric McCorkle <eric@metricspace.net>
To:        Allan Jude <allanjude@freebsd.org>
Cc:        freebsd-hackers@freebsd.org
Subject:   Re: boot1-compatible GELI and GPT code?
Message-ID:  <E4E0E2B4-86BB-4103-8A2E-99531789E322@metricspace.net>
In-Reply-To: <56EEEF5B.4010605@freebsd.org>
References:  <8F22A0E2-45A3-463B-8CAC-16BEC8DA8883@metricspace.net> <56EEEF5B.4010605@freebsd.org>

next in thread | previous in thread | raw e-mail | index | archive | help
On Mar 20, 2016, at 14:43, Allan Jude <allanjude@freebsd.org> wrote:
>=20
> I presented a paper on my work in this area (booting from a GELI
> encrypted partition, it does not GELI encrypt the GPT table) at
> AsiaBSDCon last weekend, and committed it this week.
>=20
> Here is the paper: http://allanjude.com/bsd/AsiaBSDCon2016_geliboot.pdf
>=20
> The commit was: r296963 https://svnweb.freebsd.org/changeset/base/296963

Thanks, I'll check it out.

> I am interested in applying this work to UEFI as well.

I've got a branch going on my github.  I've pushed some initial code that ad=
ds "provider modules" to boot, which basically consume a device and produce m=
ore devices.  I haven't actually written any provider modules yet though.

https://github.com/emc2/freebsd/tree/geli_efi

> Is there much advantage to encrypted the GPT table as well? Currently my
> setup leaves the partition table, and the code up to boot2 unencrypted.
> Only encrypting the actual OS partition (/boot/{zfs,}loader,
> /boot/kernel, etc). Swap is encrypted separately with a unique
> throw-away key per reboot.

Generally speaking, the less knowledge an attacker has, the better.  If they=
 know the filesystems types (obtainable from the GPT), then they know the lo=
cations of the superblocks and likely can guess at least some of the content=
s.  They also may be able to glean information from which sectors changed of=
 they can observe the disk multiple times over time.  By contrast, if all th=
ey have is a big encrypted block, it's harder to infer anything about what's=
 inside.=



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?E4E0E2B4-86BB-4103-8A2E-99531789E322>