[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: EFF misstatements in DeCSS brief



In article <[email protected]>,
lcs Mixmaster Remailer  <[email protected]> wrote:
> In <[email protected][63.193.122.223]>, Martin Minow <[email protected]>
> wrote:
> > Not being a skilled cryptanalyst, I defer to others to determine
> > the difficulty represented by 4 GB of plaintext/cyphertext,
> > a 40 bit key, and the economic/technical constraints on consumer
> > hardware.
> 
> A trivial example where even arbitrary amounts of plaintext+ciphertext
> plus knowledge of a 40-bit key will not help: [...]

Obviously, there exist ciphers which are apparently extremely hard to
deduce given just plaintext/ciphertext.

But should we necessarily believe that the CSS is one of them?  The CSS
is an extremely weak cipher design, with plenty of trivial attacks.  I
think it is entirely possible that these design flaws are serious enough
to reveal the cipher structure to anyone patient enough to look carefully.

In fact, in a separate post, I present a detailed explanation of a scenario
where it seems that a talented cryptanalyst might plausibly recover the
entire CSS algorithm using only some known plaintext/ciphertext!