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Re: MAC speeds
In message <Pine.BSI.3.91.1000315102404.16490C-100000@spsystems.net>, Henry Spe
ncer writes:
> On 14 Mar 2000, D. J. Bernstein wrote:
> > Asking how much scrutiny a Wegman-Carter-type authentication system has
> > received is like asking how much scrutiny counter mode has received:
> > you're missing the point. The security is _provably_ as good as the
> > encryption function you plug in.
>
> That just shifts the problem one step: how much scrutiny has that proof had?
> (As the infamous Demillo/Lipton/Perlis paper pointed out, proofs are just as
> subject to errors and oversights as programs are.)
Right. Also bear in mind that proofs often make assumptions about ideal
encryption functions, ideal hash functions, etc. But ideal cryptographic
functions aren't subject to things like linear and differential cryptanalysis.
--Steve Bellovin
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