Specific hidden network scan failure

Nicola Smaldone nicola.smaldone
Wed Aug 19 11:47:40 PDT 2015

Thanks Jouni, I'll do some tests with the latest snapshot. Can I also ask you if already have a schedule for the next release including that SCAN feature?

Anyway, I already did tests as I thought the ssid or channel filtered scan had to be performed and can confirm you that it worked as I believed with broadcasted ssid networks.
And repeated the same by adding the 
wpa_cli -iwlan0 enable_network 0
to the sequence just before the scan with same results.
Curiously those sequences were able to filter away all ssid different from the specified one if not hidden. For hidden networks no results were obtained at all, they were all filtered.
That's why I believed the filtered scan was possible.

Probably it's a misbehavior, or it works that way due to other reasons I don't know.
Telling you to publish my experience.

Thanks again,

-----Original Message-----
From: hostap-bounces at lists.shmoo.com [mailto:hostap-bounces at lists.shmoo.com] On Behalf Of Jouni Malinen
Sent: mercoled? 19 agosto 2015 00:44
To: hostap at lists.shmoo.com
Subject: Re: Specific hidden network scan failure

On Tue, Aug 18, 2015 at 10:01:36PM +0000, Nicola Smaldone wrote:
> And this is the scan sequence for a specific hidden ssid, let's say "mynet" on channel 3:
> 1. wpa_cli -iwlan0 remove_network 0
> 2. wpa_cli -iwlan0 add_network
> 3. wpa_cli -iwlan0 set_network 0 scan_freq 2422
> 4. wpa_cli -iwlan0 set filter_ssids 1
> 5. wpa_cli -iwlan0 ap_scan 1
> 6. wpa_cli -iwlan0 set_network 0 ssid '"mynet"'
> 7. wpa_cli -iwlan0 set_network 0 scan_ssid 1
> 8. wpa_cli -iwlan0 scan

That network block 0 is not enabled. It would need to be enabled (e.g.,
"set_network 0 disabled 0") for the SSID to be used in a scan.
Furthermore, that final scan command is not a single channel scan nor
does it use that scan_ssid information. scan_freq and scan_ssid are used
only if wpa_supplicant is triggering a scan on its own during a
connection attempt (e.g., SELECT_NETWORK or REASSOCIATE with that
network block enabled).

Please also note that with the current development snapshot, you can
also run such a scan with a command like "SCAN freq=2422 ssid
6d796e6574" without having to add the network block for it just for the
purpose of scanning.

Jouni Malinen                                            PGP id EFC895FA
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