[gnutls-help] GnuTLS testsuite error on ppc64 after nettle upgrade

[Andreas Metzler]

On 2021-02-09 Niels Möller <nisse at lysator.liu.se> wrote:
> Andreas Metzler <ametzler at bebt.de> writes:

> > I have bisected this[1] in nettle git and found
> >
> > 58a0301437e9beb23130423ff1063a67b6f2b43b
> > ppc: New assembly for chacha_core4, doing four blocks in parallel.

> This is indeed new code in nettle-3.7, and particularly suspect since
> the test fails only on ppc. Do you know what the code path is? Is GnuTLS
> using Nettle's chacha_poly1305_* functions, or is it calling chacha and
> poly1305 functions separately?

Hello,

Afaict from
https://gitlab.com/gnutls/gnutls/-/blob/master/lib/nettle/cipher.c#L815
it does use chacha_poly1305_encrypt/decrypt/update/digest/set_key/set_nonce.

I am not 100% sure. -  I thought I could brute-force this with ltrace, but I
only got it to show direct library calls to gnutls_* but not the
indirect ones (gnutls calling nettle).

cu Andreas
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