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    SubjectRe: Problem with random.c and PPC
    On Aug 16, 2002  19:45 -0500, Oliver Xymoron wrote:
    > Realistically, the hashing done by /dev/urandom is probably strong
    > enough for most purposes. It's as cryptographically strong as whatever
    > block cipher you're likely to use with it. /dev/random goes one step
    > further and tries to offer something that's theoretically
    > unbreakable. Useful for generating things like large public keys, less
    > useful for generating the session keys used by SSL and the
    > like. They're easier to break by direct attack.

    One of the problems, I believe, is that reading from /dev/urandom will
    also deplete the entropy pool, just like reading from /dev/random.
    The only difference is that when the entropy is gone /dev/random will
    stop and /dev/urandom will continue to provide data.

    If you are in there fixing things, it might make sense to have
    /dev/urandom extract entropy from the random pool far less often than
    /dev/random. This way people who use /dev/urandom for a source of
    less-strong randomness (e.g. TCP sequence numbers or whatever), will
    not be shooting themselves in the foot for when they need a 2048-byte
    PGP key, if they are low on entropy sources.

    Cheers, Andreas
    Andreas Dilger

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