wpa_supplicant: works for 10 seconds, then fails, then works..

[Jouni Malinen]

On Mon, Dec 26, 2005 at 06:59:21PM +0100, lorenzo wrote:

> wireless card: intel ipw2200

> hypotesis: I think there's something wrong with the authentication or
> group auth. Seems like if I cannot authenticate the access point after
> 10 seconds the card will disconnect. I don't know where to tell
> wpa_supplicant NOT to do this. I tried almost every combination of the
> options given in the examples, but my knowledge of the thing is not
> enough.

> wpa_driver_wext_set_key: alg=2 key_idx=0 set_tx=1 seq_len=6 key_len=32
> State: 4WAY_HANDSHAKE -> GROUP_HANDSHAKE
> 
> [and afeter 10 seconds]
> 
> Authentication with 00:40:05:55:e5:3d timed out.

Pairwise key was configured for encrypting/decrypting unicast packets,
but wpa_supplicant did not receive a Group Key message 1/2 which is
supposed to be the first encrypted frame using the pairwise keys. Based
on your description of other things working, it sounds like the pairwise
keys were configured correctly.

My first guess would be that the AP did not encrypt group key message
even though WPA specification requires that it is encrypted. Some
drivers may allow such incorrect behavior (e.g., most Windows NDIS
drivers), but it is possible that the driver you are using (ipw2200
Linux driver) does not.

Would you happen to have possibility of using a wireless sniffer to
capture what the AP is sending out during WPA handshakes?

-- 
Jouni Malinen                                            PGP id EFC895FA