
Gimli: a cross-platform permutation - andrius4669
https://gimli.cr.yp.to/
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alanbernstein
I'm not a crypto person, I have no idea what this is. To me "permutation"
refers to the mathematical concept, an "ordered arrangement of the elements of
a set". It's far from obvious to me why anyone would publish such a thing.

The disambiguation page doesn't list anything relevant either.

~~~
ghkbrew
Also, not a crypto person so someone correct me if I'm wrong, But. The
algorithm presented is essentially a way of determining the next 384bit number
in a sequence given the last one. If that sequence contains every 384bit
number before forming a cycle then it defines a mathematical permutation of
the 384bit numbers.

This sort of process is used in e.g. pseudo-random number generators. Naively,
you can for can keep 384bits internal state then at each step output the
lowest 64bits as your pseudo-random number.

~~~
alanbernstein
Funny, I've implemented such a thing before. I would call it a permutation
iterator.

