[117919] in Cypherpunks
Re: [crisp@netcom.com: Re: chips, trust, waldoes, ultranoia etc.]
daemon@ATHENA.MIT.EDU (Anonymous)
Wed Sep 15 11:16:47 1999
Date: Wed, 15 Sep 1999 16:57:25 +0200 (CEST)
Message-Id: <199909151457.QAA07954@mail.replay.com>
From: Anonymous <nobody@replay.com>
To: cypherpunks@algebra.com
Reply-To: Anonymous <nobody@replay.com>
At 08:43 PM 9/14/99 -0400, Dave Emery forwarded:
>> Ok, let me be more precise. *Mask layout people* get the final say.
>
>That is a crock of shit. No engineer that makes his chips work doesn't
>check the work of the mask designer.
Trouble parsing double negative correctly. You saying
the VHDL team goes through all the masks visually
checking for design rules, visually matching each
polygon to the corresponding HDL? I don't think so.
Extra gates get inserted for buffering, etc. As long
as the simulations agree, all is happy in silly valley.
But simulations only measures the functions you're looking for.
*Somehow* software Easter Eggs, mask Waldoes, amusing
lockup/division errors in widely deployed CPUs
all get past these engineers and their tools. With our security analysis
hats on, we have to at least ponder subversions of the
design or manufacturing stages. Think four-wire
capacitor. Think Haegelin.
<snip>
I suppose in theory a person that wrote the
>specification that defined what the chip was to do would be able to
>build in back doors, but usually there is a lot of cross checking by
>designers back to spec guys cross checked by verification people. If you
>want to build a back door, then all three really most likely would have
>to be cooperating on it.
No, because the engineers are generally not looking for
subliminal channels in the design, they're looking to see
if it will work or not, and how fast.
>> -Wait til they see the bats...
>
>This last comment was inspired by "Fear and Loathing in Las Vegas". It
>was in the book and in the movie!
Yes it was intended as an acknowledgement that
we are in the high paranoia realm here.
Just because you're paranoid doesn't mean the NSA
isn't the third largest employer in Maryland.
