Message-ID: <1339693721.9786.5.camel@jlt3.sipsolutions.net> (sfid-20120614_190848_741315_39E0D066)
Subject: Re: [PATCH] mac80211: add support for userspace to handle auth
 frames on adhoc ifaces
From: Johannes Berg <johannes@sipsolutions.net>
To: Will Hawkins <hawkinsw@opentechinstitute.org>
Cc: Nicolas Cavallari <Nicolas.Cavallari@lri.fr>,
	linux-wireless@vger.kernel.org
Date: Thu, 14 Jun 2012 19:08:41 +0200
In-Reply-To: <4FDA179F.1020501@opentechinstitute.org>
References: <4FD8B5D4.8060305@opentechinstitute.org>
	   <4FD99A24.3020907@lri.fr> <1339673095.4461.2.camel@jlt3.sipsolutions.net>
	  <4FD9DD35.4070709@lri.fr> <1339692819.9786.4.camel@jlt3.sipsolutions.net>
	 <4FDA179F.1020501@opentechinstitute.org>
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On Thu, 2012-06-14 at 12:55 -0400, Will Hawkins wrote:
> 
> On 06/14/2012 12:53 PM, Johannes Berg wrote:
> > On Thu, 2012-06-14 at 14:46 +0200, Nicolas Cavallari wrote:
> >> On 14/06/2012 13:24, Johannes Berg wrote:
> >>> On Thu, 2012-06-14 at 10:00 +0200, Nicolas Cavallari wrote:
> >>>
> >>>> I just have a question here : when auth frames are not delivered to
> >>>> userspace, mac80211 will respond to them, and also uses them to detect
> >>>> node reboot. If you register for auth frames, mac80211 will still send
> >>>> auth frames as soon as a new station is seen, which might be confusing
> >>>> for user space. Is that ok to do this ? Or should userspace have more
> >>>> control over how mac80211 sends auth frames ?
> >>>
> >>> Please read the code. If userspace registers for them, mac80211 will
> >>> never do anything with the frame.
> >>
> >> I didn't say the contrary. But if you read ieee80211_ibss_finish_sta(),
> >> you see that mac80211 sends auth frames to each discovered station, even
> >> if userspace want to handle auth frames. This seems strange to be able
> >> to receive and handle auth frames from userspace while mac80211 sends
> >> them behind userspace's back.
> > 
> > Oops, sorry, yes. I forgot all about that code!
> > 
> > I suppose we'd have to check whether userspace is handling
> > authentication?
> 
> Could use the control_port flag to check for that condition?

Not really, that's not necessarily the same thing -- I think we might
want to also allow to offload open auth to userspace.

I think it wouldn't be difficult to notify mac80211 about frame
registrations so it can keep track for this purpose?

johannes