dynamic vlan with ath10k not working - regression

[Guenther Kelleter]

Hi 

At first please excuse my ignorance but I'm new to WiFi and hostapd and don't know yet how all this is working.

> -----Original Message-----
> From: michael-dev [mailto:michael-dev at fami-braun.de]
> Sent: Thursday, May 12, 2016 3:03 AM
> To: Guenther Kelleter
> Cc: hostap at lists.infradead.org
> Subject: Re: dynamic vlan with ath10k not working - regression
> 
> Hi,
> 
> Am 11.05.2016 16:25, schrieb Guenther Kelleter:
> > Since commit 7cebc8e2100626dc6981a3f53301058452953b9b, "Fix init of
> > group state machine for static VLANs" dynamic VLAN isn't working with
> > atk10k radio anymore. Parent commit works as expected.
> 
> basically this fix added wpa group key initialization during ap_vlan
> interface creation, that is before any station is assigned to the
> driver.
> This is required for static VLANs with WPA where AP_VLAN interfaces are
> created possibly long before any station connects.

What exactly is not working in the static VLAN case?
I can configure an SSID to be part of a non-dynamic vlan in OpenWrt, i.e. that all stations are put in the configured vlan-bridge. This doesn't create a wlan0.<VLAN-ID> interface but uses the plain wlan0. I can't see anything not working in this case before this fix was added.
Maybe you're talking about a different thing?

> 
> > Symptom is that neither wlanX-Y.<VLAN-ID> nor the corresponding
> > vlan-bridge is created. Association fails.
> 
> The driver refuses to accept the key. Therefore that per VLAN wpa_group
> enters state FATAL_FAILURE, thus stations cannot complete group keying.
> 
> Solutions
> a) make ath10k accept group keys without any station connected

I understand even less of the driver than of hostapd :-) It's a pitch black box...

> b) let hostapd skip set_key without any stations connected if this is a
> dynamic vlan. This means static VLANs will continue to not work with
> ath10k.

Hmmm... looking at the code I'm not sure how to do that
Prevent calling wpa_group_setkeysdone? 

> 
> I unsure which would be best?
> 
> > I tried the same with ath9k radio: works as expected with both
> > versions.
> >
> > This is the relevant debug log of hostapd:
> >
> > wlan0-2: STA 78:7e:61:61:15:a3 RADIUS: VLAN ID 20
> 
> so we add the new ap_vlan interface due to a station needing it.
> 
> > nl80211: New interface wlan0-2.20 created: ifindex=60
> 
> that interface has ifindex=60 assigned
> 
> > VLAN: Set interface wlan0-2.20 up
> 
> and is configured ifconfig_up
> 
> > WPA: Add group state machine for VLAN-ID 20
> 
> now wpa group keying starts before the station was assigned to the
> driver
> 
> > wpa_driver_nl80211_set_key: ifindex=60 (wlan0-2.20) alg=3
> > addr=0x496be4 key_idx=1 set_tx=1 seq_len=0 key_len=16
> 
> a wpa group key shall be configured to the wireless driver
> 
> > nl80211: set_key failed; err=-22 Invalid argument)
> 
> but the driver does not like it. I don't know why. It should not.
> 
> > WPA: group state machine entering state FATAL_FAILURE
> 
> so the group state machine blocks and
> 
> > WPA initialization for VLAN 20 failed (-1)
> 
> interface initialization is declared failing
> 
> Regards,
> M. Braun


Günther