Re: mac80211/iwlwifi + hidden ssids

[Dan Williams <dcbw@redhat.com>]

On Wed, 2007-10-10 at 16:57 +0200, dragoran wrote:
> On 10/10/07, Dan Williams <dcbw@redhat.com> wrote:
> >[..]
> > wpa_supplicant's support for hidden SSIDs sort of sucks; mainly because
> > the drivers implement this in different ways.  wpa_supplicant says you
> > must use "ap_scan=2" for hidden SSIDs (and possibly ssid_scan=1 to do
> > specific ssid probe requests), which causes wpa_supplicant to blast all
> > settings to the card directly and not try to be smart about AP scanning
> > and selection.  However, this doesn't work often because drivers are
> > inconsistent about this.
> >
> > The way it _should_ work is that if scan_ssid = 1 for a network,
> > wpa_supplicant should ask that the driver scan the specific ssid using
> > IW_SCAN_THIS_ESSID.  The card would then issue specific SSID scan
> > requests on each channel during the scan, and hopefully find the AP in
> > question.
> >
> > Unfortunately, most drivers don't support IW_SCAN_THIS_ESSID.  So the
> > best we can do is set AP_SCAN=2, let wpa_supplicant blow all the
> > settings to the card, and just _hope_ that the card/driver are smart
> > enough to find the hidden SSID on their own and associate.  Which is
> > less often than we'd hope.
> 
> so your are suggestion to use ap_scan=2 and add scan_ssid=1 to the
> network block?
> nm seems not to do this.

It should be doing this...

> btw shouldn't all mac80211 drivers either work or not work because the
> code for this is in mac80211 and not in the drivers?

Yeah, pretty much; but each driver/firmware may handle hidden ssids
slightly differently.  mac80211 should bring some sanity to this area,
but I wouldn't discount variation between even mac80211 based drivers.

Dan

> I will be able to test again this friday will try this and the
> ap_scan=1 if there are other suggestion feel free to say them so I can
> add them to my "totest" list ;)