WPA-PSK hostapd+madwifi-ng <--> DLink DWL-G810 interop problems

[Duncan Gibb]

Hi

I've built an access point using a Soekris net4801 and a Gigabyte
GN-WP01GT (Atheros 5005GS PCI).  It's running Debian Sarge with a
mainline-ish 2.6.16.2 Linux kernel.  I rebuilt Faidon Liambotis's .deb
of hostapd 0.5.2 against the madwifi-ng r1497 drivers and set up a
WPA-PSK network.

It's working fine with a laptop running a proprietary operating system,
but I also want to add a couple of DLink DWL-G810 wifi-to-wired ethernet
bridges (UK model rev C1 = Atheros-in-a-box) to connect some non-wifi
devices without drilling holes in my house.

Originally, I kept getting loops of "WPA_PTK entering state PTKSTART ...
WPA: EAPOL-Key timeout" in threes every few seconds.  I read about Bug
89 (broken clients drop packets with EAPOL version set to 2), but I
couldn't find a patch to fix just that issue, and the process to
Debianise a CVS head snapshot was not obvious enough for the time
available (sorry), so I rebuilt 0.5.2 again with EAPOL_VERSION defined
to 1.  Now I'm seeing this:

__
ath0: STA 00:11:95:04:bb:c3 IEEE 802.11: associated
  New STA
ath0: STA 00:11:95:04:bb:c3 WPA: event 1 notification
madwifi_del_key: addr=00:11:95:04:bb:c3 key_idx=0
ath0: STA 00:11:95:04:bb:c3 WPA: start authentication
WPA: 00:11:95:04:bb:c3 WPA_PTK entering state INITIALIZE
madwifi_del_key: addr=00:11:95:04:bb:c3 key_idx=0
ath0: STA 00:11:95:04:bb:c3 IEEE 802.1X: unauthorizing port
madwifi_set_sta_authorized: addr=00:11:95:04:bb:c3 authorized=0
WPA: 00:11:95:04:bb:c3 WPA_PTK_GROUP entering state IDLE
WPA: 00:11:95:04:bb:c3 WPA_PTK entering state AUTHENTICATION
WPA: 00:11:95:04:bb:c3 WPA_PTK entering state AUTHENTICATION2
WPA: 00:11:95:04:bb:c3 WPA_PTK entering state INITPSK
WPA: 00:11:95:04:bb:c3 WPA_PTK entering state PTKSTART
ath0: STA 00:11:95:04:bb:c3 WPA: sending 1/4 msg of 4-Way Handshake
WPA: Send EAPOL(secure=0 mic=0 ack=1 install=0 pairwise=1 ie_len=0 gtk_len=0 keyidx=0 encr=0)
TX EAPOL - hexdump(len=113): 00 11 95 04 bb c3 00 14 85 2e 01 9e 88 8e 01 03 00 5f fe 00 89 00 20 00 00 00 00 00 00 00 01 32 68 8d 3
3 87 96 60 79 96 c8 5a 49 c5 56 4f 50 d3 77 3b c5 95 7b 75 7e 51 de a8 17 af 34 9e 79 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ath0: STA 00:11:95:04:bb:c3 WPA: EAPOL-Key timeout
WPA: 00:11:95:04:bb:c3 WPA_PTK entering state PTKSTART
ath0: STA 00:11:95:04:bb:c3 WPA: sending 1/4 msg of 4-Way Handshake
WPA: Send EAPOL(secure=0 mic=0 ack=1 install=0 pairwise=1 ie_len=0 gtk_len=0 keyidx=0 encr=0)
TX EAPOL - hexdump(len=113): 00 11 95 04 bb c3 00 14 85 2e 01 9e 88 8e 01 03 00 5f fe 00 89 00 20 00 00 00 00 00 00 00 02 32 68 8d 3
3 87 96 60 79 96 c8 5a 49 c5 56 4f 50 d3 77 3b c5 95 7b 75 7e 51 de a8 17 af 34 9e 79 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
IEEE 802.1X: 125 bytes from 00:11:95:04:bb:c3
   IEEE 802.1X: version=1 type=3 length=121
ath0: STA 00:11:95:04:bb:c3 WPA: WPA IE from (Re)AssocReq did not match with msg 2/4
WPA IE in AssocReq - hexdump(len=24): dd 16 00 50 f2 01 01 00 00 50 f2 02 01 00 00 50 f2 02 01 00 00 50 f2 02
WPA IE in msg 2/4 - hexdump(len=26): dd 16 00 50 f2 01 01 00 00 50 f2 02 01 00 00 50 f2 02 01 00 00 50 f2 02 00 00
hostapd_wpa_auth_disconnect: WPA authenticator requests disconnect: STA 00:11:95:04:bb:c3 reason 2
madwifi_sta_deauth: addr=00:11:95:04:bb:c3 reason_code=2
ath0: STA 00:11:95:04:bb:c3 IEEE 802.11: deauthenticated due to local deauth request
Wireless event: cmd=0x8c04 len=20
ath0: STA 00:11:95:04:bb:c3 IEEE 802.11: disassociated
__

It looks to me like hostapd is expecting two extra zero bytes at the end
of the AssocReq, which it's not getting from the DLinks.  But I don't
know which end is wrong or what the right behaviour should be.

Since I'm new to wifi beyond using an idiot-proof GUI to hook up to an
existing AP, I'd appreciate someone who knows more narrowing down the
problem space for me.  I reckon it's one of:

 - bad firmware in the DLinks (v3.10, 14 Feb 2005, latest)

 - outdated or wrongly built hostapd (is there an easy way
   to Debianise a CVS snap?)

 - compatibility issue between madwifi-ng and hostapd

 - obscure GCC problem (drivers and kernel were built with
   3.2; hostapd was built with 3.3)


Where should I look first?


Cheers


Duncan