Question about seqbuf in cipher-chacha-libcrypto.c

[Damien Miller]

On Wed, 21 Apr 2021, rapier wrote:

> For various reasons I'd like to be able to understand how the block
> counter is handled cipher-chacha-libcrypto.c (mostly to test something
> that will probably go nowhere).

I don't have any insight into the problem you're seeing except to note
that you don't seem to be doing anything obviously wrong.

As a suggestion, maybe try your experiment in the included portable
implementation of the cipher (i.e. cipher-chachapoly.c) - there's
less magic behind the scenes there compared to libcrypto and it's easier
to insert a bunch of printf()s to see what is actually being supplied to
the chacha20 primitive.

-d