[Prism54-devel] New advances

[Jean-Baptiste Note]

Hello Feyd, Sebastien, dear list,

Well, that's it, i've got real monitor mode working ! This is OK in
non-madwifi mode only (compile with make MADWIFI=0), but now

iwconfig ethX mode monitor

followed by an ethereal on the ethX device will show you every packets,
ack, etc... on a given channel. You can obviously change channels with
iwconfig ethX channel Y.

This is tested on both my devices and works perfectly. Please test on
yours :)

While i'm at it, i thought that i'd rather finish up with the rx frames
and decode the remaining fields in the packet : so i've embedded the
remaining unknown values in the data_rate, antenna and priority fields
of the AVS frame that you'll capture in ethereal. This way the data is
elegantly displayed and can be easily analysed.

"priority" is closely related to the type of frame (see the hardcoded
values P54U_RX_MONITORXX_ID in p54u_protocol.h). The other two are not
known. I suspect data rate (unknown1 field) to be rate related (eh... i
should'nt have chosen this AVS field, because i'm really not sure), the
other seem utterly unknown.

I'm real happy, because with this we can do something that we have never
seen the windows driver do. Na ! 

The magic bit was in the first field of the rx_filter packet, which is
different when you're not associtated (0), associated to an AP (1), or
in ad-hoc mode (2). Monitor mode was some higher bit ; I hit the bingo
when trying 0x10. You'll see the packet when iwconfig mode monitoring
the card. There are still some fields unknown in this packet. So if you
don't see some packets that you know are sent on the air, please report
them, so we can figure out what's filtered additionally.

I've successfully tested the effects of another bit in this "rx_filter"
packet. What do you think of a field that has an effect on the rssi?
with this bit enabled, i get fewer packets (weaker ones seem discarded),
and their rssi is different. Would someone have a clue ?

JB

-- 
Jean-Baptiste Note
+33 (0)6 83 03 42 38
jean-baptiste.note at wanadoo.fr