Re: [EXT] Re: [PATCH net-next v5 3/7] net: macsec: indicate next pn update when offloading

Hi guys,

On 21.09.2023 18:11, Sabrina Dubroca wrote:

quoted

2023-09-20, 12:22:33 +0300, Radu Pirea (NXP OSS) wrote:

quoted

Indicate next PN update using update_pn flag in macsec_context.
Offloaded MACsec implementations does not know whether or not the
MACSEC_SA_ATTR_PN attribute was passed for an SA update and assume
that next PN should always updated, but this is not always true.

This should probably go through net so that we can fix some drivers
that are currently doing the wrong thing. octeontx2 should be
fixable. atlantic looks like it would reset the PN to whatever was
read during the last dump, and it's unclear if that can be fixed
(AFAIU set_egress_sa_record writes the whole config at once).  mscc

Thats correct, atlantic hardware requires full table to be in data buffer registers.
I really doubt its possible to skip PN writing.

quoted

doesn't seem to modify the PN (even if requested -- should it should
reject the update), and mlx5 doesn't allow PN update (by storing the
initial value of next_pn on SA creation).

I updated octeontx2, mssc and mlx5. Atlantic is unclear.

Mark, Igor, in the atlantic MACsec driver, can the SAs be updated
without a PN update?

Reviewed the code and the docs I have - my view is it can not.
All the packed record in macsec_api.c:set_egress_sa_record is expected by hardware in full.

Regards,
  Igor