Stefan Bühler nettle-bugs@stbuehler.de writes:
My preference, if you want to have a fixed length in the name, is still "chacha_set_key128" and similar. Not sure about "chacha_128_set_key", "chacha20_128_set_key", ...
Thanks for the feedback.
As a side note: the paper for Chacha only mentions the 256-bit key variant,
Interesting, I hadn't noticed that.
although the reference implementation also provides the 128-bit variant...
But the reference code really is very close to salsa20, it even uses "salsa20" in the name of one if the internal functions.
So I'm not sure whether the 128-bit variant was actually intended being used at all.
Does anyone else know of use or interest in 128-bit chacha keys? It would definitely make things a bit simpler if we can omit support for 128-bit keys. (And if we skip it now, we could of course reintroduce it later if it turns out to be needed).
Regards, /Niels