WPA2-PSK with TKIP fails to set GTK/PTK to driver: ioctl[IEEE80211_IOCTL_SETMODE]: No such device or address

Jouni Malinen jkmaline
Wed Feb 14 19:57:44 PST 2007

On Tue, Feb 13, 2007 at 03:00:53AM +0200, kstauffer wrote:

> RSN pre-authentication seems to be enabled in ProST AP and RSN PTKSA 
> Reply Counter is 1.
> I enabled pre-authentication from hostapd and checked if it  behaves the 
> same as ProST board, but it worked nicely.
> Could it be that the RSN PTKSA Reply Counter is causing 4way Handshake 
> to be restarted, even Authentication were succesfull?

In theory, but at least wpa_supplicant does not care about it.

> What is the meaning of those PTKSA/GTKSA Reply Counter capabilities?

It tells how many replay counters are supported. When WMM is used, there
are multiple transmit queues and packets may be re-ordered (i.e., high
priority packets can be sent out before low priority once) and this
re-ordering can happen after packet numbers has been assigned to the
frames. WPA/WPA2 need multiple replay counters to handle such
re-ordering without dropping packets as replay attacks. I don't know
whether any driver really uses these values, but anyway, I would expect
devices that support WPA/WPA2 with WMM to support at least four replay

Jouni Malinen                                            PGP id EFC895FA

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