madwifi + hidden SSID

[Jouni Malinen]

On Sun, Jun 11, 2006 at 02:16:14PM +0200, Fabio Sangiovanni wrote:

> I've read on this list that not all the drivers support AP scanning, so 
> wpa_supplicant can't associate to the AP (with hidden ssid) if the 
> driver hasn't this feature.
> What about madwifi? Both with ap_scan=2 and with ap_scan=1 + scan_ssid=1 
> I didn't get it working on startup, but if I set an ssid manually with 
> iwconfig, all works perfectly.

I think I've seen both cases working with madwifi driver. However, there
are some details that are not ideal. For example, -Dmadwifi case sets
SSID for scanning with SIOCSIWSCAN which may break the existing
connection. Anyway, this question could be more relevant on the madwifi
mailing lists. My preference would be to make -Dwext case work reliably
and that would mean making sure madwifi supports SIOCSIWSCAN with extra
data added in WEXT v18 for per-SSID scan in case of
ap_scan=1/scan_ssid=1 and ap_scan=2 case should just work by allowing
the driver to do AP selection based on the configured SSID.

> The only solution to the problem seems to be launching wpa_supplicant 
> with the parameter -D wext, so using wireless extensions' ioctl instead 
> of madwifi's.
> ap_scan=2 works perfectly this way, and the nic associates *very* fast.
> 
> I'd like to know from you if there's a way to use -D madwifi with hidden 
> SSID (in this case it would be just a problem of my configuration), or 
> if madwifi doesn't support ap scanning at all.

Linux drivers should really move to use generic wireless extensions
instead of private ioctls for the cases where a generic ioctl is
defined. In other words, I would recommend using -Dwext with madwifi
instead of -Dmadwifi and reporting any possibly remaining issues to
driver developers.

-- 
Jouni Malinen                                            PGP id EFC895FA