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SubjectRe: [PATCH] (0/4) Entropy accounting fixes
On Mon, Sep 16, 2002 at 03:51:56PM -0700, dean gaudet wrote:
> On Mon, 9 Sep 2002, Oliver Xymoron wrote:
> > making the RNG guessable is relatively easy. On the other hand
> > determining whether a given snippet of code is doing RSA, etc. is
> > equivalent to solving the halting problem, so it's seems to me pretty
> > damn hard to usefully put this sort of back door into a CPU without
> > sacrificing general-purpose functionality.
> while the general problem is certainly halting-problem level of
> complexity, there's a much more simple problem which amounts to string
> matching. the simple problem is "is this a specific portion of openssl /
> cryptoapi / whatever?"
> if you consider a technology like transmeta's which only has to
> compile/translate code infrequently (rather than a traditional technology
> with decoders running all the time) then it's pretty easy to see how you
> could use a few cycles to do the string matching.

If you're the compiler, it's pretty damn easy. If you're the CPU
watching the instruction stream generated by an unknown compiler for a
lengthy piece of code with context switches and interrupts going on,
it's back to being nontrivial again. It's simply much easier to
backdoor the RNG..

"Love the dolphins," she advised him. "Write by W.A.S.T.E.."
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