[PATCH v2 07/14] AP: Rename SAE anti clogging variables and functions

Jouni Malinen j at w1.fi
Tue Jan 26 06:00:37 EST 2021

On Tue, Jan 26, 2021 at 07:01:26AM +0000, Peer, Ilan wrote:
> So eventually this patch would end up by only renaming internal functions and
> variables? Are you introducing another configuration option to also set the
> PASN anti clogging?

I was first planning to just rename the internal functions and variables
as part of these patch series. However, now that I thought more about
the PASN comeback mechanism after your replies and after having re-read
P802.11ax/D2.6, I think I'll just skip all the patches related to the
comeback mechanism for now to get the rest of the patch series applied.
It is starting look clear that the comeback mechanism needs more thought
on both the AP and the station sides.

For the station side (patch 10/14), I see no point in using external
mechanism for the special case mentioned in the draft, i.e., when
Comeback After value of 0 is used. That is just like the SAE
anti-clogging mechanism, i.e., immediate retry with the cookie, and that
needs to happen automatically within wpa_supplicant. The case with
nonzero Comeback After value seems reasonable to handle external based
on your explanation.

For the AP side, this PASN mechanism is much more flexible than the SAE
one since there is an explicit indication of Comeback After and the
reasons for using this can be quite different. As such, it may not be
reasonable to share the same configuration parameter for this with SAE.
Furthermore, the hardcoded value of 10 TUs for Comeback After may not be
the best approach (0 TUs would sounds like a better default behavior,
but there may be other reasons for the AP to behave more dynamically in
this area).. And that was actually incorrectly documented in
wpa_pasn_add_parameter_ie() as being seconds, not TUs..

Jouni Malinen                                            PGP id EFC895FA

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