Message-ID: <1496050303.2467.3.camel@sipsolutions.net> (sfid-20170529_113150_652842_94250423)
Subject: Re: [PATCH V2 0/9] nl80211: add support for PTK/GTK handshake
 offload
From: Johannes Berg <johannes@sipsolutions.net>
To: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: linux-wireless <linux-wireless@vger.kernel.org>,
        "hostap@lists.infradead.org" <hostap@lists.infradead.org>
Date: Mon, 29 May 2017 11:31:43 +0200
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Hi Arend,

> > Note that this (checking NEW_KEY) only works when you don't have
> > any split between AP/client cases. Not sure what's the case for
> > you.
> 
> Late response so hopefully you recall, but what do you mean by "any 
> split between AP/client cases"?

I meant the capability split - let's say you support 4-way-HS only for
client, but not for AP. Then you have to support the NEW_KEY command
for the AP case, even if you might not support non-offloaded 4-way-HS
for the client case.

So if something supports the following:

 * client: offloaded 4-way-HS only
 * AP: not offloaded 4-way-HS only

Then you have to support NEW_KEY (AP case) and then using NEW_KEY to
detect whether or not a wpa_s configuration option to not use offloaded
4-way-HS can be used will not work correctly.

I don't really see that this is a sensible configuration, but I could
imagine it existing if somebody "bolted on" AP functionality for a
client-side chipset or something like that.

Again, I think I'm happy to leave this up to you - this kind of
configuration option should really only be used for debugging anyway,
so just getting errors later is probably fine.

johannes