Re: [Etherboot-developers] Securing bootup

[<ke...@us...>]

>An idea struck me today as I was thinking about a way to more securely

Hope it wasn't too painful. :-)

>verify that the client that is booting via Etherboot is actually
>downloading the kernel/code that you really want it to.  Use a preshared
>key built into the Etherboot code that is flashed onto the bootrom to
>validate the kernel image/code.  So, in order for the client to
>successfully boot, the image it downloads has to be digitally signed and
>that signature has to match when signed by the clients Etherboot key.
>Otherwise the client refuses to boot.  There could be a number of ways
>to go about this, from having a default "Etherboot" maintained key and
>signature to a site-by-site basis where the administrator/deployer would
>build there own version of Etherboot to embed their own key for their
>own thin client workstations.

Or a key in a USB dongle.

There is/was a uni project working on secure booting in general, don't
have the URL handy, Eric has it.

Eric's got a hook in 5.1 that verifies download integrity using a
checksum over the image. Verifying a signature is an obvious extension.

>Another possibility that this presents is to not only authenticate the
>connection but also be able to create an encrypted tunnel using
>Diffie-Hellman key exchange.  This may be a rather involved process just
>to get a secure boot layer, but it may open up the doors to a larger
>audience and wider acceptance of Etherboot.

Tunnels are much harder. Etherboot only implements UDP.

>What do you all think?

Great idea, looking forward to seeing your code soon. :-)

But seriously, it's a good idea worth developing further, but as always
implementation depends on someone keen enough to contribute some time to
do it.