Usage report / open discussions tab?

[infogulch]

Hi! I finished (enough) of my use-case for the GaloisFields.jl package that I thought I'd share as thanks for your time and trouble answering my vague, peculiar questions. I hope you might even find it interesting. 😄

I published as a Pluto.jl notebook on my blog: List hash as matrices over finite fields, which explores the idea of defining the hash of a list of elements with the key feature that the hash is composable with other list hashes. The definition goes something like: hash each entry of the list, interpret each hash digest as a matrix with GF(256) elements (rejecting and retrying singular matrices), define the hash of the whole list to be reduction by matrix multiplication of the matrix hashes of all the elements.

I reference a previous post where I try to do the same thing over the ring of integers mod 256, but that doesn't work because it's very likely that random matrices over such a ring are singular, and after multiplying enough of them the list hash degenerates into the zero matrix. A patient soul on crypto stackoverflow corrected me and suggested GF(256) as an alternative, which is how I found myself here (after deciding for some reason to switch from python to Julia which I'd never used before).

As far as analyzing the security of such a construction I'm quite out of my depth. That said, I'm not aware of any prior cryptographic primitive that features associativity, which I think could open up many use cases for cryptographic security of mutable lists that have thus far been under-served.

If you so choose I'd gladly welcome any feedback or criticism, but in any case thanks for the great library and for all your help.

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This post might be more appropriate as a discussion, you might consider enabling the Discussions feature on the repo here on github. Anyways, since this isn't really an issue, feel free to close whenever you like.

[tkluck]

Congrats on the blog post, it looks like very nice work!