Option to set interface to 4-addr mode

[Jouni Malinen]

On Sun, Oct 16, 2022 at 12:21:33AM +0300, Konstantinos Natsakis wrote:
> Would you be interested in a patch for wpa_supplicant that adds a new
> command line option to set an interface to 4-address mode?

Using a command line option for this sounds strange to me. Isn't the
4-address mode going to be used based on the actual network rather than
as a global setting?

> Does it make more sense, perhaps, to always set an interface to 4-addr mode
> when the `-b` option is present?

I'm not convinced this would be the correct thing to do for all cases
and as such, would rather avoid potentially breaking something and not
change existing behavior.

> Some context: I did some work on https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1330
> (Support setting 4-addr (WDS) mode per WiFi connection), and it was
> suggested that wpa_supplicant should handle setting 4-addr mode of the
> interface, which I too think make sense.

That "per WiFi connection" part would seem to point towards having a per
network profile configuration parameter instead of a global parameter
for this. As an example, the multi_ap_backhaul_sta parameter mentioned
in that discussion uses an approach that could be more appropriate here.
Doing the same for 4-address mode part without the full Multi AP
functionality using a new per-network parameter could be the way to go
with this type of functionality.

-- 
Jouni Malinen                                            PGP id EFC895FA