Re: [Cfrg] I-D Action: draft-nir-cfrg-chacha20-poly1305-01.txt

[Ted Krovetz <[e-mail]>]

> I guess I should change the text to say that it’s a little-endian representation of integers limited to 32 bits.

I would recommend that you never use endianess to describe integers. An integer is an integer, and endianess has only to do with cpu-memory interfacing. An integer can be read little-endian from memory, but the resulting integer is not a little-endian integer, it's just an integer. It may be clearest to talk about inputs and output being strings and each successive 32-bit chunk getting byte-reversed.

So, for example, the input to chacha is a 256-bit key string, 96-bit nonce string and 32-bit unsigned integer. The first thing that happens in chacha is the key and nonce are split into 32-bit unsigned integers by byte reversing each 32-bit chunk and then interpreting each 32-bit chunk as an unsigned integer. Now we're in the realm of integers, and the word endianess is never mentioned.

-Ted