building a true RNG

[Paul Crowley]

David Wagner <daw at cs.berkeley.edu> writes:
> I don't know of any good cryptographic hash function that comes with
> a proof that all outputs are possible.  However, it might not be too
> hard to come up with plausible examples.  For example, if we apply the
> Luby-Rackoff construction (i.e., 3 rounds of a Feistel cipher), with
> ideal hash functions in each round, does this have the desired properties?
> It might.

This seems to define a block cipher with no key, which is collision
free but not one-way.  Am I misunderstanding what you're proposing?
-- 
  __  Paul Crowley
\/ o\ sig at paul.ciphergoth.org
/\__/ http://www.ciphergoth.org/

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