Ethereal-users: Re: [Ethereal-users] Wireless sniffing - FreeBSD 4.5 + Cisco LMC352?

Note: This archive is from the project's previous web site, ethereal.com. This list is no longer active.

From: Doug Ambrisko <ambrisko@xxxxxxxxxxxx>
Date: Thu, 13 Jun 2002 09:20:33 -0700 (PDT)
Guy Harris writes:
| On Wed, Jun 12, 2002 at 09:55:12AM -0700, Doug Ambrisko wrote:
| > I got my laptop back and this is the "hack" I did:
| > 
| > Index: packet-ieee80211.c
| > ===================================================================
| > RCS file: /cvsroot/ethereal/packet-ieee80211.c,v
| > retrieving revision 1.53
| > diff -c -r1.53 packet-ieee80211.c
| > *** packet-ieee80211.c	2002/04/08 09:09:47	1.53
| > --- packet-ieee80211.c	2002/06/12 16:51:00
| > ***************
| > *** 1521,1527 ****
| >   	  if (cap_len > 0 && pkt_len > 0)
| >   	    call_dissector(data_handle,tvb_new_subset(tvb, hdr_len + 4, -1,tvb_reported_length_remaining(tvb,hdr_len + 4)),pinfo, tree);
| >   	}
| > - 	return;
| >       }
| >   
| >     /*
| > --- 1521,1526 ----
| > 
| > I did it a long time ago.  Basically I just let it fall into the part
| > that does:
| > 	Now dissect the body of a non-WEP-encrypted frame.
| > and life is good if I set the WEP key on the card.  Of course this
| > is for WEP enscrypted packets.
| 
| Great.  So the driver can't just clear the WEP bit, as the WEP
| information is in the decrypted frames it delivers.

That seems to be the case.  BTW I'm using 0.8.20 from old CVS version.
I will try to update my CVS tree and re-compile but I'm afraid since
that usually breaks my build :-(  I think I have it figured out this time.

| Perhaps we'd need to have a preference setting in the 802.11 dissector
| to control whether to assume WEP frames are decrypted or encrypted?

Yep this is a pain.  I don't know if it is an Aironet feature?

Doug A.