2 * Routines for arcnet dissection
3 * Copyright 2001-2002, Peter Fales <ethereal@fales-lorenz.net>
7 * Wireshark - Network traffic analyzer
8 * By Gerald Combs <gerald@wireshark.org>
9 * Copyright 1998 Gerald Combs
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version 2
14 * of the License, or (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
34 #include <epan/packet.h>
35 #include "packet-arcnet.h"
36 #include <epan/arcnet_pids.h>
37 #include "packet-ip.h"
39 /* Initialize the protocol and registered fields */
40 static int proto_arcnet = -1;
41 static int hf_arcnet_src = -1;
42 static int hf_arcnet_dst = -1;
43 static int hf_arcnet_offset = -1;
44 static int hf_arcnet_protID = -1;
45 static int hf_arcnet_exception_flag = -1;
46 static int hf_arcnet_split_flag = -1;
47 static int hf_arcnet_sequence = -1;
49 /* Initialize the subtree pointers */
50 static gint ett_arcnet = -1;
52 static dissector_table_t arcnet_dissector_table;
53 static dissector_handle_t data_handle;
56 capture_arcnet (const guchar *pd, int len, packet_counts *ld,
57 gboolean has_offset, gboolean has_exception)
59 int offset = has_offset ? 4 : 2;
61 if (!BYTES_ARE_IN_FRAME(offset, len, 1)) {
68 case ARCNET_PROTO_IP_1051:
69 /* No fragmentation stuff in the header */
70 capture_ip(pd, offset + 1, len, ld);
73 case ARCNET_PROTO_IP_1201:
75 * There's fragmentation stuff in the header.
77 * XXX - on at least some versions of NetBSD, it appears that we
78 * might we get ARCNET frames, not reassembled packets; we should
79 * perhaps bump "ld->other" for all but the first frame of a packet.
81 * XXX - but on FreeBSD it appears that we get reassembled packets
82 * on input (but apparently we get frames on output - or maybe
83 * we get the packet *and* all its frames!); how to tell the
84 * difference? It looks from the FreeBSD reassembly code as if
85 * the reassembled packet arrives with the header for the first
86 * frame. It also looks as if, on output, we first get the
87 * full packet, with a header containing none of the fragmentation
88 * stuff, and then get the frames.
90 * On Linux, we get only reassembled packets, and the exception
91 * frame stuff is hidden - there's a split flag and sequence
92 * number, but it appears that it will never have the exception
95 * XXX - what about OpenBSD? And, for that matter, what about
96 * Windows? (I suspect Windows supplies reassembled frames,
97 * as WinPcap, like PF_PACKET sockets, taps into the networking
98 * stack just as other protocols do.)
101 if (!BYTES_ARE_IN_FRAME(offset, len, 1)) {
105 if (has_exception && pd[offset] == 0xff) {
106 /* This is an exception packet. The flag value there is the
107 "this is an exception flag" packet; the next two bytes
108 after it are padding, and another copy of the packet
109 type appears after the padding. */
112 capture_ip(pd, offset + 3, len, ld);
115 case ARCNET_PROTO_ARP_1051:
116 case ARCNET_PROTO_ARP_1201:
118 * XXX - do we have to worry about fragmentation for ARP?
123 case ARCNET_PROTO_IPX:
134 dissect_arcnet_common (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree,
135 gboolean has_offset, gboolean has_exception)
138 guint8 dst, src, protID, split_flag;
140 proto_item *ti = NULL;
141 proto_tree *arcnet_tree = NULL;
143 col_set_str (pinfo->cinfo, COL_PROTOCOL, "ARCNET");
145 col_set_str(pinfo->cinfo, COL_INFO, "ARCNET");
147 src = tvb_get_guint8 (tvb, 0);
148 dst = tvb_get_guint8 (tvb, 1);
149 SET_ADDRESS(&pinfo->dl_src, AT_ARCNET, 1, tvb_get_ptr(tvb, 0, 1));
150 SET_ADDRESS(&pinfo->src, AT_ARCNET, 1, tvb_get_ptr(tvb, 0, 1));
151 SET_ADDRESS(&pinfo->dl_dst, AT_ARCNET, 1, tvb_get_ptr(tvb, 1, 1));
152 SET_ADDRESS(&pinfo->dst, AT_ARCNET, 1, tvb_get_ptr(tvb, 1, 1));
154 ti = proto_tree_add_item (tree, proto_arcnet, tvb, 0, -1, ENC_NA);
156 arcnet_tree = proto_item_add_subtree (ti, ett_arcnet);
158 proto_tree_add_uint (arcnet_tree, hf_arcnet_src, tvb, offset, 1, src);
161 proto_tree_add_uint (arcnet_tree, hf_arcnet_dst, tvb, offset, 1, dst);
165 proto_tree_add_item (arcnet_tree, hf_arcnet_offset, tvb, offset, 2, ENC_NA);
169 protID = tvb_get_guint8 (tvb, offset);
170 proto_tree_add_uint (arcnet_tree, hf_arcnet_protID, tvb, offset, 1, protID);
175 case ARCNET_PROTO_IP_1051:
176 case ARCNET_PROTO_ARP_1051:
177 case ARCNET_PROTO_DIAGNOSE:
178 case ARCNET_PROTO_BACNET: /* XXX - no fragmentation? */
179 /* No fragmentation stuff in the header */
184 * Show the fragmentation stuff - flag and sequence ID.
186 * XXX - on at least some versions of NetBSD, it appears that
187 * we might get ARCNET frames, not reassembled packets; if so,
188 * we should reassemble them.
190 * XXX - but on FreeBSD it appears that we get reassembled packets
191 * on input (but apparently we get frames on output - or maybe
192 * we get the packet *and* all its frames!); how to tell the
193 * difference? It looks from the FreeBSD reassembly code as if
194 * the reassembled packet arrives with the header for the first
195 * frame. It also looks as if, on output, we first get the
196 * full packet, with a header containing none of the fragmentation
197 * stuff, and then get the frames.
199 * On Linux, we get only reassembled packets, and the exception
200 * frame stuff is hidden - there's a split flag and sequence
201 * number, but it appears that it will never have the exception
204 * XXX - what about OpenBSD? And, for that matter, what about
205 * Windows? (I suspect Windows supplies reassembled frames,
206 * as WinPcap, like PF_PACKET sockets, taps into the networking
207 * stack just as other protocols do.)
209 split_flag = tvb_get_guint8 (tvb, offset);
210 if (has_exception && split_flag == 0xff) {
211 /* This is an exception packet. The flag value there is the
212 "this is an exception flag" packet; the next two bytes
213 after it are padding. */
214 proto_tree_add_uint (arcnet_tree, hf_arcnet_exception_flag, tvb, offset, 1,
218 proto_tree_add_text (arcnet_tree, tvb, offset, 2, "Padding");
221 /* Another copy of the packet type appears after the padding. */
222 proto_tree_add_item (arcnet_tree, hf_arcnet_protID, tvb, offset, 1, ENC_BIG_ENDIAN);
225 /* And after that comes the real split flag. */
226 split_flag = tvb_get_guint8 (tvb, offset);
229 proto_tree_add_uint (arcnet_tree, hf_arcnet_split_flag, tvb, offset, 1,
233 proto_tree_add_item (arcnet_tree, hf_arcnet_sequence, tvb, offset, 2, ENC_BIG_ENDIAN);
239 /* Set the length of the ARCNET header protocol tree item. */
240 proto_item_set_len(ti, offset);
242 next_tvb = tvb_new_subset_remaining (tvb, offset);
244 if (!dissector_try_uint (arcnet_dissector_table, protID,
245 next_tvb, pinfo, tree))
247 col_add_fstr (pinfo->cinfo, COL_PROTOCOL, "0x%04x", protID);
248 call_dissector (data_handle, next_tvb, pinfo, tree);
254 * BSD-style ARCNET headers - they don't have the offset field from the
255 * ARCNET hardware packet, but we might get an exception frame header.
258 dissect_arcnet (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
260 dissect_arcnet_common (tvb, pinfo, tree, FALSE, TRUE);
264 * Linux-style ARCNET headers - they *do* have the offset field from the
265 * ARCNET hardware packet, but we should never see an exception frame
269 dissect_arcnet_linux (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
271 dissect_arcnet_common (tvb, pinfo, tree, TRUE, ENC_BIG_ENDIAN);
274 static const value_string arcnet_prot_id_vals[] = {
275 {ARCNET_PROTO_IP_1051, "RFC 1051 IP"},
276 {ARCNET_PROTO_ARP_1051, "RFC 1051 ARP"},
277 {ARCNET_PROTO_IP_1201, "RFC 1201 IP"},
278 {ARCNET_PROTO_ARP_1201, "RFC 1201 ARP"},
279 {ARCNET_PROTO_RARP_1201, "RFC 1201 RARP"},
280 {ARCNET_PROTO_IPX, "IPX"},
281 {ARCNET_PROTO_NOVELL_EC, "Novell of some sort"},
282 {ARCNET_PROTO_IPv6, "IPv6"},
283 {ARCNET_PROTO_ETHERNET, "Encapsulated Ethernet"},
284 {ARCNET_PROTO_DATAPOINT_BOOT, "Datapoint boot"},
285 {ARCNET_PROTO_DATAPOINT_MOUNT, "Datapoint mount"},
286 {ARCNET_PROTO_POWERLAN_BEACON, "PowerLAN beacon"},
287 {ARCNET_PROTO_POWERLAN_BEACON2, "PowerLAN beacon2"},
288 {ARCNET_PROTO_APPLETALK, "Appletalk"},
289 {ARCNET_PROTO_BANYAN, "Banyan VINES"},
290 {ARCNET_PROTO_DIAGNOSE, "Diagnose"},
291 {ARCNET_PROTO_BACNET, "BACnet"},
296 proto_register_arcnet (void)
299 /* Setup list of header fields See Section 1.6.1 for details*/
300 static hf_register_info hf[] = {
302 {"Source", "arcnet.src",
303 FT_UINT8, BASE_HEX, NULL, 0,
307 {"Dest", "arcnet.dst",
308 FT_UINT8, BASE_HEX, NULL, 0,
312 {"Offset", "arcnet.offset",
313 FT_BYTES, BASE_NONE, NULL, 0,
317 {"Protocol ID", "arcnet.protID",
318 FT_UINT8, BASE_HEX, VALS(arcnet_prot_id_vals), 0,
321 {&hf_arcnet_split_flag,
322 {"Split Flag", "arcnet.split_flag",
323 FT_UINT8, BASE_DEC, NULL, 0,
326 {&hf_arcnet_exception_flag,
327 {"Exception Flag", "arcnet.exception_flag",
328 FT_UINT8, BASE_HEX, NULL, 0,
331 {&hf_arcnet_sequence,
332 {"Sequence", "arcnet.sequence",
333 FT_UINT16, BASE_DEC, NULL, 0,
334 "Sequence number", HFILL}
338 /* Setup protocol subtree array */
339 static gint *ett[] = {
343 arcnet_dissector_table = register_dissector_table ("arcnet.protocol_id",
344 "ARCNET Protocol ID",
347 /* Register the protocol name and description */
348 proto_arcnet = proto_register_protocol ("ARCNET", "ARCNET", "arcnet");
350 /* Required function calls to register the header fields and subtrees used */
351 proto_register_field_array (proto_arcnet, hf, array_length (hf));
352 proto_register_subtree_array (ett, array_length (ett));
357 proto_reg_handoff_arcnet (void)
359 dissector_handle_t arcnet_handle, arcnet_linux_handle;
361 arcnet_handle = create_dissector_handle (dissect_arcnet, proto_arcnet);
362 dissector_add_uint ("wtap_encap", WTAP_ENCAP_ARCNET, arcnet_handle);
364 arcnet_linux_handle = create_dissector_handle (dissect_arcnet_linux,
366 dissector_add_uint ("wtap_encap", WTAP_ENCAP_ARCNET_LINUX, arcnet_linux_handle);
367 data_handle = find_dissector ("data");