XO-2

[John Watlington]

On May 22, 2008, at 11:36 AM, Carl-Daniel Hailfinger wrote:

> On 22.05.2008 17:01, C. Scott Ananian wrote:
>> On 5/22/08, Carl-Daniel Hailfinger <c-d.hailfinger.devel. 
>> 2006 at gmx.net> wrote:
>>
>>>>  h) hardware-protected RTC (bitfrost desiderata)
>>> I'd be very interested in the reasons for that. P_THEFT is still  
>>> mostly
>>>  unimplemented for cost reasons. A hardware-protected RTC will not
>>>  improve the current state at all as long as the hardware side of  
>>> P_THEFT
>>>  is not implemented. It will certainly raise cost, though.
>>>
>>
>> Not the case: epoxy-coating the motherboard was not cost-effective,
>> meaning that the cost of bypassing P_THEFT by circuit-board changes
>> was already expensive enough to be infeasible -- and of course epoxy
>> adds to manufacture, repair, and rework costs.  The economics weren't
>> with it.
>>
>
> As I stated before on this list, bypassing P_THEFT is very easy. You
> don't even have to desolder the complete flash chip, one pin is
> sufficient. All of this is doable for less than $1 per laptop if you
> have access to cheap labor. $1 per laptop is _not_ expensive enough to
> be infeasible. I am very willing to publish a video tutorial of the
> procedure if you think I can't do that. The only downside would be  
> that
> everybody then knows how to bypass P_THEFT.

If all it takes is accessing one pin, then epoxy is even less useful.

>> We actually know exactly how much it costs to bypass P_THEFT in bulk,
>> since some of original manufacture run ended up with a firmware bug
>> which bricked them in exactly the way P_THEFT would.
>>
>
> If you came up with a cost of more than $2, the recovery/bypass was
> missing the obvious shortcuts or you had a requirement not to solder.
>