Re: [PATCH ipsec-next v9] xfrm: Add Direction to the SA in or out

[Antony Antony <antony.antony@secunet.com>]

On Thu, Apr 11, 2024 at 11:04:21 +0200, Steffen Klassert wrote:
> On Thu, Apr 11, 2024 at 11:01:32AM +0200, Nicolas Dichtel wrote:
> > 
> > 
> > Le 11/04/2024 à 09:14, Steffen Klassert a écrit :
> > > On Wed, Apr 10, 2024 at 08:32:20AM +0200, Nicolas Dichtel wrote:
> > >> Le 09/04/2024 à 19:56, Antony Antony a écrit :
> > >>> This patch introduces the 'dir' attribute, 'in' or 'out', to the
> > >>> xfrm_state, SA, enhancing usability by delineating the scope of values
> > >>> based on direction. An input SA will now exclusively encompass values
> > >>> pertinent to input, effectively segregating them from output-related
> > >>> values. This change aims to streamline the configuration process and
> > >>> improve the overall clarity of SA attributes.
> > >>>
> > >>> This feature sets the groundwork for future patches, including
> > >>> the upcoming IP-TFS patch.
> > >>>
> > >>> Signed-off-by: Antony Antony <antony.antony@secunet.com>
> > >>> ---
> > >>> v8->v9:
> > >>>  - add validation XFRM_STATE_ICMP not allowed on OUT SA.
> > >>>
> > >>> v7->v8:
> > >>>  - add extra validation check on replay window and seq
> > >>>  - XFRM_MSG_UPDSA old and new SA should match "dir"
> > >>>
> > >>> v6->v7:
> > >>>  - add replay-window check non-esn 0 and ESN 1.
> > >>>  - remove :XFRMA_SA_DIR only allowed with HW OFFLOAD
> > >> Why? I still think that having an 'input' SA used in the output path is wrong
> > >> and confusing.
> > > 
> > > I don't think this can happen. This patch does not change the
> > > state lookups, so we should match the correct state as it was
> > > before that patch.
> > This is the point. The user can set whatever direction in the SA, there is no
> > check. He can set the dir to 'output' even if the SA is used in input.
> 
> Ah, yes indeed. That should be fixed, thanks for clarification!

I have v10 with two simple packet path checks and error counters as
Sabrina suggested. I imagine this would avoid inconsitancy Nicolas trying to
avoid.