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Re: Eliminating the "rehash" mechanism for 5.18

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Leon Timmermans
October 30, 2012 15:47
Re: Eliminating the "rehash" mechanism for 5.18
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On Tue, Oct 30, 2012 at 10:57 PM, Eric Brine <> wrote:
>  How many hashes does one need to build to
> determine the seed?

If brute-force is the only method, quite a lot. If you don't control
the contents of the output even more for statistical reasons. The only
brute force way that I can think of is to eliminate all possible seeds
until only one is left. However, hash order is not a function of only
the seed but also of insertion order (when they're put in the same
bucket) and bucket count. This sounds effectively impossible to me for
all practical purposes.

Though maybe someone smarter than me can think of a more effective
attack than brute-force.


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