haskell-crypto / cryptonite

lowlevel set of cryptographic primitives for haskell
Other
226 stars 139 forks source link

Add support for XChaCha and XChaChaPoly1305 #365

Closed MatthiasValvekens closed 12 months ago

MatthiasValvekens commented 2 years ago

This PR adds support for the extended nonce variants of ChaCha and ChaChaPoly1305, as implemented in libsodium (among others), and specified in this RFC draft: https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-xchacha-03. Like #364, I'm submitting this PR because I'd like to have this functionality in another project of mine that depends on cryptonite.

Since the only difference with the "base" cipher lies in the way the initial state is generated, the only change(s) in the Haskell API are a couple new initialisation functions & associated types. I considered overloading the existing initialize functions and branching on the length of the nonce, but I figured keeping them separate would be cleaner.

This addition did require a number of additions at the C level, though (mainly to implement the extra HChaCha primitive). I haven't written any "serious" C in a while, so some extra attention would be appreciated there. Obviously, comments on other aspects of the implementation are also more than welcome.

Thanks a lot!

vincenthz commented 2 years ago

thanks for the contribution, that looks useful and looks good, but you need to fix the indentation of the C files are mixed, make sure your editor default to tab / noexpand

MatthiasValvekens commented 2 years ago

Oh, good catch. I didn't notice, and my editor is indeed set to expand all tabs. My bad, I'll fix that tonight. Thanks!

MatthiasValvekens commented 2 years ago

Hi @vincenthz, I converted the indentation in the C files to use tabs instead of spaces. I preserved spaces where used for alignment rather than indentation, though (in this case: function signatures spanning multiple lines).

If there's anything else I need to change, please let me know. Thanks!

PS: I checked my other PR #364 as well, just to make sure. That one seems to be OK as far as indentation is concerned.

vincenthz commented 12 months ago

archiving repository