On Wed, Nov 10, 2004 at 09:30:56AM -0500, David Hudak wrote:
> Hi,
> 
> Question for the group:  I am using NetBSD 2.0 with an Atheros 5212 
> radio.  I put the radio in monitor mode and do tcpdump -D IEEE802_11... 
> I have seen the following...
> 1.  beacons
> 2.  probe requests, probe responses
> 3.  auth requests, auth responses
> 4.  association requests, association responses
> 5.  data frames
> 
> But, I have not seen any 802.11 ACKs.  Is this expected behavior?  I 
> know that they are there, since a sniff with KisMAC using an original 
> Apple Airport (i.e., Orinoco) card shows them.

That's a bug.  There are a few problems, beginning with this check
in ath_rx_proc,

                len = ds->ds_rxstat.rs_datalen;
                if (len < IEEE80211_MIN_LEN) {
                        DPRINTF(ATH_DEBUG_RECV, ("%s: short packet %d\n",
                                __func__, len));
                        sc->sc_stats.ast_rx_tooshort++;
                        goto rx_next;
                }

It looks to me like that check can be postponed until a few lines later
when the WEP header is stripped.  These days, it's ok to pass a short
frame to net80211, which taps the IEEE802_11 DLT.

(Now that I am looking at ath_rx_proc, I'd sure like to revamp its
radiotap section.)

Dave

-- 
David Young             OJC Technologies
dyoung@ojctech.com      Urbana, IL * (217) 278-3933