On Thu, 21 Jun 2007, Lennart Sorensen wrote:

quoted text
> On Thu, Jun 21, 2007 at 10:26:04AM -0700, david@lang.hm wrote:
>> the bios doesn't have enough capability to talk to the outside world for
>> updates.
>
> Of course, although perhaps it could.  More likely my thought was that
> the service when it decides to download an update, would include the
> updated bios image and put it on the boot drive where the existing bios
> can find it.  No signature needs to be added to the boot drive or
> kernel, just checksums in the bios image.
>
>> what tivo actually does is very similar to this
>>
>> they encode into the bios the ability to check a checksum/signature for
>> the kernel+boot filesystem and if they don't match look to see if there is
>> another kernel+boot filesystem available
>>
>> then software on the boot filesystem checks to see if the rest of the
>> system has been tampered with before it mounts /

you snippede the bit about not knowing how to stop it

quoted text
>> the GPLv3 is trying to do this.
>
> Perhaps they should just explicitly say that then.

they call the section the anti-tivoization, how much more explicit can 
they get?

David Lang

by the way, just in case anyone is misunderstanding me. I don't believe 
for a moment that all these anti-tamper features actually work in the real 
world (the PS3 hacking kits are proof of the lengths people will go to to 
make the 'hard' hardware-level hacking trivial to do) but the approach 
needs to be at secure modulo hardware tampering or software bugs.

-
unsubscribe notice
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/