8051 enthusiast

@8051enthusiast
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pronounshe/they
thanks to @jhwgh1968 there is now a windows build as well! you can grab it from the same release page
#bash protip: add apostrophes to your commands to clarify their meaning
and while i'm at it, i've also finally released version 1.0.0 which has lots of new features!
https://github.com/8051Enthusiast/delsum/releases/tag/v1.0.0
Release Release v1.0.0 · 8051Enthusiast/delsum

Many changes this release: Change the module parameter to be named modulus Change all hexadecimal parameters to now need a 0x prefix Add new polyhash algorithm kind Add JSON output Add -t option f...

GitHub
my web frontend skills are pretty much nonexistent, so if something looks weird that's just me being bad at this
i made an online version of delsum, this will hopefully make it easier to use for identifying checksum algorithms
https://8051enthusiast.github.io/delsum
Delsum

obj2yaml | yq | yaml2obj has no right working this well, i didn't encounter any strange issues (i was probably just lucky because this was a small library though)
ah yes, "linker scripts"

this also means that i can finally get delsum to compile to wasm, which didn't work out when i tried with NTL's perl build scripts

it is fairly slow on wasm, mostly because wasm doesn't have a clmul instruction, but if the files are 500kb in size it should be fine

made a rust crate for big GF(2) polynomials (using the gf2x library for multiplications, at least for now)
https://github.com/8051Enthusiast/gf2poly
GitHub - 8051Enthusiast/gf2poly: GF(2) polynomial arithmetic

GF(2) polynomial arithmetic. Contribute to 8051Enthusiast/gf2poly development by creating an account on GitHub.

GitHub
neat little fact about CRCs and stream ciphers: if you append a CRC to a message, you always get the same CRC.
if you encrypt the resulting message with a stream cipher, the CRC of the message is cancelled out so you essentially get the CRC of the keystream. as a result, if you encrypt 2 different files of same length with CRC appended with the same (unsalted) key, you get the same CRC on the encrypted file