I guess some bridges take Netware Ethernet_802_3 frames, which are 802.3

frames (with a length field rather than a type field, but with no 802.2
header in the payload), and just stick the payload into an 802.11 frame.
I've seen captures that show frames of that sort.

This means we have to do the same check for Netware 802.3 - or, if you
will, "Netware 802.11" - that we do in the Ethernet dissector, i.e.
checking for 0xffff as the first four bytes of the payload and, if we
find it, treating it as an IPX frame.

svn path=/trunk/; revision=3759

1 files changed, 49 insertions, 4 deletions

diff --git a/packet-ieee80211.c b/packet-ieee80211.c
index 09727c5b86..308cb48904 100644
--- a/packet-ieee80211.c
+++ b/packet-ieee80211.c
@@ -3,7 +3,7 @@
  * Copyright 2000, Axis Communications AB 
  * Inquiries/bugreports should be sent to Johan.Jorgensen@axis.com
  *
- * $Id: packet-ieee80211.c,v 1.36 2001/06/22 08:12:11 guy Exp $
+ * $Id: packet-ieee80211.c,v 1.37 2001/07/21 06:30:21 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -65,6 +65,7 @@
 #include "proto.h"
 #include "packet.h"
 #include "resolv.h"
+#include "packet-ipx.h"
 #include "packet-llc.h"
 #include "packet-ieee80211.h"
 #include "etypes.h"
@@ -338,6 +339,7 @@ static gint ett_tagged_parameters = -1;
 static gint ett_wep_parameters = -1;
 
 static dissector_handle_t llc_handle;
+static dissector_handle_t ipx_handle;
 
 /* ************************************************************************* */
 /*            Return the length of the current header (in bytes)             */
@@ -398,7 +400,23 @@ capture_ieee80211 (const u_char * pd, int offset, packet_counts * ld)
     case DATA_CF_POLL:
     case DATA_CF_ACK_POLL:
       hdr_length = find_header_length (fcf);
-      capture_llc (pd, offset + hdr_length, ld);
+      /* I guess some bridges take Netware Ethernet_802_3 frames,
+         which are 802.3 frames (with a length field rather than
+         a type field, but with no 802.2 header in the payload),
+         and just stick the payload into an 802.11 frame.  I've seen
+         captures that show frames of that sort.
+
+         This means we have to do the same check for Netware 802.3 -
+         or, if you will, "Netware 802.11" - that we do in the
+         Ethernet dissector, i.e. checking for 0xffff as the first
+         four bytes of the payload and, if we find it, treating it
+         as an IPX frame. */
+      if (pd[offset+hdr_length] == 0xff && pd[offset+hdr_length+1] == 0xff) {
+        capture_ipx (pd, offset + hdr_length, ld);
+      }
+      else {
+        capture_llc (pd, offset + hdr_length, ld);
+      }
       break;
 
     default:
@@ -1016,6 +1034,7 @@ dissect_ieee80211 (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
   guint16 hdr_len;
   tvbuff_t *next_tvb;
   guint32 addr_type;
+  volatile gboolean is_802_2;
 
   if (check_col (pinfo->fd, COL_PROTOCOL))
     col_set_str (pinfo->fd, COL_PROTOCOL, "IEEE 802.11");
@@ -1411,7 +1430,32 @@ dissect_ieee80211 (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 
 
     case DATA_FRAME:
-      call_dissector (llc_handle, next_tvb, pinfo, tree);
+      /* I guess some bridges take Netware Ethernet_802_3 frames,
+         which are 802.3 frames (with a length field rather than
+         a type field, but with no 802.2 header in the payload),
+         and just stick the payload into an 802.11 frame.  I've seen
+         captures that show frames of that sort.
+
+         This means we have to do the same check for Netware 802.3 -
+         or, if you will, "Netware 802.11" - that we do in the
+         Ethernet dissector, i.e. checking for 0xffff as the first
+         four bytes of the payload and, if we find it, treating it
+         as an IPX frame. */
+      is_802_2 = TRUE;
+      TRY {
+        if (tvb_get_ntohs(next_tvb, 0) == 0xffff)
+          is_802_2 = FALSE;
+      }
+      CATCH2(BoundsError, ReportedBoundsError) {
+	    ; /* do nothing */
+
+      }
+      ENDTRY;
+
+      if (is_802_2)
+        call_dissector(llc_handle, next_tvb, pinfo, tree);
+      else
+        call_dissector(ipx_handle, next_tvb, pinfo, tree);
       break;
     }
 }
@@ -1812,9 +1856,10 @@ void
 proto_reg_handoff_wlan(void)
 {
   /*
-   * Get a handle for the LLC dissector.
+   * Get handles for the LLC and IPX dissectors.
    */
   llc_handle = find_dissector("llc");
+  ipx_handle = find_dissector("ipx");
 
   dissector_add("wtap_encap", WTAP_ENCAP_IEEE_802_11, dissect_ieee80211,
 		proto_wlan);