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    SubjectRe: [PATCH] random: add blocking facility to urandom
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    On Fri, 09 Sep 2011 10:21:13 +0800, Sandy Harris said:
    > Barring a complete failure of SHA-1, an enemy who wants to
    > infer the state from outputs needs astronomically large amounts
    > of both data and effort.

    So let me get this straight - the movie-plot attack we're defending against is
    somebody readin literally gigabytes to terabytes (though I suspect realistic
    attacks will require peta/exabytes) of data from /dev/urandom, then performing
    all the data reduction needed to infer the state of enough of the entropy pool
    to infer all 160 bits of SHA-1 when only 80 bits are output...

    *and* doing it all without taking *any* action that adds any entropy to the
    pool, and *also* ensuring that no other programs add any entropy via their
    actions before the reading and data reduction completes. (Hint - if the
    attacker can do this, you're already pwned and have bigger problems)

    /me thinks RedHat needs to start insisting on random drug testing for
    their security experts at BSI. EIther that, or force BSI to share the
    really good stuff they've been smoking, or they need to learn how huge
    a number 2^160 *really* is....

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