[Colin Slater <kiltedtaco@xxxxxxxxx>]

Attached is a patch for basic decoding of packets from Turbocell
(formerly produced by karlnet, now Terabeam Wireless) wireless
networks. The networks are 802.11b based, but a proprietary header is
inserted between the 802.11b header and standard encapsulated
ethernet. As it is undocumented, the fields the patch decodes are only
my best guesses. The patch does reliably decode data packets though,
and hands those packets off to the ethernet dissector after removing
the turbocell header. If anyone would like packet traces of these
turbocell networks, or if you have packet traces, contact me off-list.

Colin

Index: oui.h
===================================================================
--- oui.h	(revision 12768)
+++ oui.h	(working copy)
@@ -35,6 +35,7 @@
 #define OUI_CABLE_BPDU	0x00E02F	/* DOCSIS spanning tree BPDU */
 #define	OUI_APPLE_ATALK	0x080007	/* Appletalk */
 #define	OUI_HP		0x080009	/* Hewlett-Packard */
+#define	OUI_TURBOCELL   0x0020F6    /* KarlNet, who brought you Turbocell */
 
 extern const value_string oui_vals[];
 
Index: epan/dissectors/packet-turbocell.c
===================================================================
--- epan/dissectors/packet-turbocell.c	(revision 0)
+++ epan/dissectors/packet-turbocell.c	(revision 0)
@@ -0,0 +1,217 @@
+/* packet-turbocell.c
+ * Routines for Turbocell Header dissection
+ * Copyright 2004, Colin Slater <kiltedtaco@xxxxxxxxx>
+ *
+ * $Id$
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@xxxxxxxxxxxx>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+
+
+
+/* This dissector was written entirely from reverse engineering captured
+ * packets. No documentation was used or supplied by Karlnet. Hence, this
+ * dissector is very incomplete. If you have any insight into decoding
+ * these packets, or if you can supply packet captures from turbocell 
+ * networks, contact kiltedtaco@xxxxxxxxx */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <glib.h>
+
+#include <epan/packet.h>
+
+#include "oui.h"
+
+/* Initialize the protocol and registered fields */
+static int proto_turbocell = -1;
+static int hf_turbocell_type = -1;
+static int hf_turbocell_baseid = -1;
+static int hf_turbocell_counter = -1;
+static int hf_turbocell_station_number = -1;
+static int hf_turbocell_name = -1;
+static int hf_turbocell_base[6];
+
+/* Initialize the subtree pointers */
+static gint ett_turbocell = -1;
+static gint ett_network = -1;
+
+/* The ethernet dissector we hand off to */
+static dissector_handle_t eth_handle;
+
+/* Guesses at what the first byte of the protocol id means */
+static const value_string hf_turbocell_type_values[] = {
+		{ 0x00, "Beacon" },
+		{ 0x01, "Management Packet" },
+		{ 0x11, "Data packet" },
+		{ 0, NULL }
+};
+		
+
+static void
+dissect_turbocell(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+
+    proto_item *ti, *name_item;
+    proto_tree *turbocell_tree, *network_tree;
+	tvbuff_t    *next_tvb;
+	int i;
+
+    if (tree) {
+
+        ti = proto_tree_add_item(tree, proto_turbocell, tvb, 0, -1, FALSE);
+
+		turbocell_tree = proto_item_add_subtree(ti, ett_turbocell);
+
+        proto_tree_add_item(turbocell_tree,
+            hf_turbocell_type, tvb, 0, 1, FALSE);
+
+		proto_tree_add_item(turbocell_tree,
+			hf_turbocell_baseid, tvb, 4, 6, FALSE);
+
+		proto_tree_add_item(turbocell_tree,
+			hf_turbocell_station_number, tvb, 10, 1, FALSE);
+
+		proto_tree_add_item(turbocell_tree,
+			hf_turbocell_counter, tvb, 2, 2, FALSE);
+
+
+        if(tvb_get_guint8(tvb,0) == 0xA0) {
+				
+			name_item = proto_tree_add_item(turbocell_tree,
+				hf_turbocell_name, tvb, 0x14, 10,  FALSE);
+			network_tree = proto_item_add_subtree(name_item, ett_network);
+
+			for(i = 0; i<6; i++) {
+				proto_tree_add_item(network_tree,
+					hf_turbocell_base[i], tvb, 0x34+8*i, 6, FALSE);
+			}
+		}				
+    }
+
+	if((tvb_get_guint8(tvb,0) == 0x11)||(tvb_get_guint8(tvb,0) == 0x01)) {
+		/* The hardcoded 0x1A offset here is where the ethernet header
+		 * appears to always start. It would not suprize me if it changed
+		 * between different networks, though. */
+		next_tvb = tvb_new_subset(tvb, 0x1a, -1, -1);
+		call_dissector(eth_handle, next_tvb, pinfo, tree);
+	} else {
+		if (check_col(pinfo->cinfo, COL_INFO))
+			col_set_str(pinfo->cinfo, COL_INFO, "Turbocell Packet (Unknown)");
+
+		 if (check_col(pinfo->cinfo, COL_PROTOCOL))
+	         col_set_str(pinfo->cinfo, COL_PROTOCOL, "Turbocell");
+
+	}
+}
+
+
+/* Register the protocol with Ethereal */
+
+void proto_register_turbocell(void)
+{
+
+    static hf_register_info hf[] = {
+        { &hf_turbocell_type,
+            { "Packet Type",           "turbocell.type",
+            FT_UINT8, BASE_HEX, hf_turbocell_type_values, 0,
+            "I don't know", HFILL }
+        },
+		{ &hf_turbocell_baseid,
+			{ "Base Station ID", "turbocell.baseid",
+			FT_ETHER, BASE_HEX, NULL, 0,
+			"Seems to stay constant per base station", HFILL }
+		},
+        { &hf_turbocell_station_number,
+            { "Station Number", "turbocell.stationnum",
+            FT_UINT8, BASE_HEX, NULL, 0,
+            "Seems to stay constant per station", HFILL }
+        },
+		{ &hf_turbocell_counter,
+			{ "Counter", "turbocell.counter",
+			FT_UINT16, BASE_DEC, NULL, 0,
+			"Increments alot", HFILL }
+		},
+		{ &hf_turbocell_name,
+			{ "Network Name", "turbocell.name",
+			FT_STRINGZ, 0, 0, 0,
+			"Name", HFILL }
+		},
+        { &hf_turbocell_base[0],
+            { "Base 0", "turbocell.base0",
+            FT_ETHER, BASE_HEX, NULL, 0,
+            "Base station ID?", HFILL }
+        },
+        { &hf_turbocell_base[1],
+            { "Base 1", "turbocell.base1",
+            FT_ETHER, BASE_HEX, NULL, 0,
+            "Base station ID?", HFILL }
+        },
+        { &hf_turbocell_base[2],
+            { "Base 2", "turbocell.base2",
+            FT_ETHER, BASE_HEX, NULL, 0,
+            "Base station ID?", HFILL }
+        },
+        { &hf_turbocell_base[3],
+            { "Base 3", "turbocell.base3",
+            FT_ETHER, BASE_HEX, NULL, 0,
+            "Base station ID?", HFILL }
+        },
+        { &hf_turbocell_base[4],
+            { "Base 4", "turbocell.base4",
+            FT_ETHER, BASE_HEX, NULL, 0,
+            "Base station ID?", HFILL }
+        },
+        { &hf_turbocell_base[5],
+            { "Base 5", "turbocell.base5",
+            FT_ETHER, BASE_HEX, NULL, 0,
+            "Base station ID?", HFILL }
+        }
+    };
+
+    static gint *ett[] = {
+        &ett_turbocell,
+		&ett_network,
+    };
+    proto_turbocell = proto_register_protocol("Turbocell Header",
+        "turbo", "turbocell");
+
+	register_dissector("turbocell", dissect_turbocell, proto_turbocell);
+
+    proto_register_field_array(proto_turbocell, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+}
+
+
+void proto_reg_handoff_turbocell(void)
+{
+    dissector_handle_t turbocell_handle;
+
+	eth_handle = find_dissector("eth_withoutfcs");
+
+    turbocell_handle = create_dissector_handle(dissect_turbocell,
+        proto_turbocell);
+} 
Index: epan/dissectors/Makefile.common
===================================================================
--- epan/dissectors/Makefile.common	(revision 12768)
+++ epan/dissectors/Makefile.common	(working copy)
@@ -509,6 +509,7 @@
 	packet-tr.c	\
 	packet-trmac.c	\
 	packet-tsp.c	\
+	packet-turbocell.c \
 	packet-tuxedo.c	\
 	packet-tzsp.c	\
 	packet-ucp.c	\
Index: epan/dissectors/packet-llc.c
===================================================================
--- epan/dissectors/packet-llc.c	(revision 12768)
+++ epan/dissectors/packet-llc.c	(working copy)
@@ -85,7 +85,9 @@
 static dissector_handle_t fddi_handle;
 static dissector_handle_t tr_handle;
 static dissector_handle_t data_handle;
+static dissector_handle_t turbo_handle;
 
+
 /*
  * Group/Individual bit, in the DSAP.
  */
@@ -180,6 +182,7 @@
 	{ OUI_APPLE_ATALK, "Apple (AppleTalk)" },
 	{ OUI_NORTEL,      "Nortel Networks SONMP" },
 	{ OUI_HP,          "Hewlett-Packard" },
+	{ OUI_TURBOCELL,   "Karlnet (Turbocell)" },
 	{ 0,               NULL }
 };
 
@@ -565,6 +568,11 @@
 		next_tvb = tvb_new_subset(tvb, offset+5, -1, -1);
 		call_dissector(bpdu_handle, next_tvb, pinfo, tree);
 		break;
+	
+	case OUI_TURBOCELL: 
+		next_tvb = tvb_new_subset(tvb, offset+3, -1, -1);
+		call_dissector(turbo_handle, next_tvb, pinfo, tree);
+		break;
 
 	default:
 		/*
@@ -732,6 +740,7 @@
 	fddi_handle = find_dissector("fddi");
 	tr_handle = find_dissector("tr");
 	data_handle = find_dissector("data");
+	turbo_handle = find_dissector("turbocell");
 
 	llc_handle = find_dissector("llc");
 	dissector_add("wtap_encap", WTAP_ENCAP_ATM_RFC1483, llc_handle);