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.
32 #include <epan/packet.h>
33 #include "packet-arcnet.h"
34 #include <epan/arcnet_pids.h>
35 #include "packet-ip.h"
37 /* Initialize the protocol and registered fields */
38 static int proto_arcnet = -1;
39 static int hf_arcnet_src = -1;
40 static int hf_arcnet_dst = -1;
41 static int hf_arcnet_offset = -1;
42 static int hf_arcnet_protID = -1;
43 static int hf_arcnet_exception_flag = -1;
44 static int hf_arcnet_split_flag = -1;
45 static int hf_arcnet_sequence = -1;
47 /* Initialize the subtree pointers */
48 static gint ett_arcnet = -1;
50 static dissector_table_t arcnet_dissector_table;
51 static dissector_handle_t data_handle;
54 capture_arcnet (const guchar *pd, int len, packet_counts *ld,
55 gboolean has_offset, gboolean has_exception)
57 int offset = has_offset ? 4 : 2;
59 if (!BYTES_ARE_IN_FRAME(offset, len, 1)) {
66 case ARCNET_PROTO_IP_1051:
67 /* No fragmentation stuff in the header */
68 capture_ip(pd, offset + 1, len, ld);
71 case ARCNET_PROTO_IP_1201:
73 * There's fragmentation stuff in the header.
75 * XXX - on at least some versions of NetBSD, it appears that we
76 * might we get ARCNET frames, not reassembled packets; we should
77 * perhaps bump "ld->other" for all but the first frame of a packet.
79 * XXX - but on FreeBSD it appears that we get reassembled packets
80 * on input (but apparently we get frames on output - or maybe
81 * we get the packet *and* all its frames!); how to tell the
82 * difference? It looks from the FreeBSD reassembly code as if
83 * the reassembled packet arrives with the header for the first
84 * frame. It also looks as if, on output, we first get the
85 * full packet, with a header containing none of the fragmentation
86 * stuff, and then get the frames.
88 * On Linux, we get only reassembled packets, and the exception
89 * frame stuff is hidden - there's a split flag and sequence
90 * number, but it appears that it will never have the exception
93 * XXX - what about OpenBSD? And, for that matter, what about
94 * Windows? (I suspect Windows supplies reassembled frames,
95 * as WinPcap, like PF_PACKET sockets, taps into the networking
96 * stack just as other protocols do.)
99 if (!BYTES_ARE_IN_FRAME(offset, len, 1)) {
103 if (has_exception && pd[offset] == 0xff) {
104 /* This is an exception packet. The flag value there is the
105 "this is an exception flag" packet; the next two bytes
106 after it are padding, and another copy of the packet
107 type appears after the padding. */
110 capture_ip(pd, offset + 3, len, ld);
113 case ARCNET_PROTO_ARP_1051:
114 case ARCNET_PROTO_ARP_1201:
116 * XXX - do we have to worry about fragmentation for ARP?
121 case ARCNET_PROTO_IPX:
132 dissect_arcnet_common (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree,
133 gboolean has_offset, gboolean has_exception)
136 guint8 dst, src, protID, split_flag;
138 proto_item *ti = NULL;
139 proto_tree *arcnet_tree = NULL;
141 col_set_str (pinfo->cinfo, COL_PROTOCOL, "ARCNET");
143 col_set_str(pinfo->cinfo, COL_INFO, "ARCNET");
145 src = tvb_get_guint8 (tvb, 0);
146 dst = tvb_get_guint8 (tvb, 1);
147 SET_ADDRESS(&pinfo->dl_src, AT_ARCNET, 1, tvb_get_ptr(tvb, 0, 1));
148 SET_ADDRESS(&pinfo->src, AT_ARCNET, 1, tvb_get_ptr(tvb, 0, 1));
149 SET_ADDRESS(&pinfo->dl_dst, AT_ARCNET, 1, tvb_get_ptr(tvb, 1, 1));
150 SET_ADDRESS(&pinfo->dst, AT_ARCNET, 1, tvb_get_ptr(tvb, 1, 1));
152 ti = proto_tree_add_item (tree, proto_arcnet, tvb, 0, -1, ENC_NA);
154 arcnet_tree = proto_item_add_subtree (ti, ett_arcnet);
156 proto_tree_add_uint (arcnet_tree, hf_arcnet_src, tvb, offset, 1, src);
159 proto_tree_add_uint (arcnet_tree, hf_arcnet_dst, tvb, offset, 1, dst);
163 proto_tree_add_item (arcnet_tree, hf_arcnet_offset, tvb, offset, 2, ENC_NA);
167 protID = tvb_get_guint8 (tvb, offset);
168 proto_tree_add_uint (arcnet_tree, hf_arcnet_protID, tvb, offset, 1, protID);
173 case ARCNET_PROTO_IP_1051:
174 case ARCNET_PROTO_ARP_1051:
175 case ARCNET_PROTO_DIAGNOSE:
176 case ARCNET_PROTO_BACNET: /* XXX - no fragmentation? */
177 /* No fragmentation stuff in the header */
182 * Show the fragmentation stuff - flag and sequence ID.
184 * XXX - on at least some versions of NetBSD, it appears that
185 * we might get ARCNET frames, not reassembled packets; if so,
186 * we should reassemble them.
188 * XXX - but on FreeBSD it appears that we get reassembled packets
189 * on input (but apparently we get frames on output - or maybe
190 * we get the packet *and* all its frames!); how to tell the
191 * difference? It looks from the FreeBSD reassembly code as if
192 * the reassembled packet arrives with the header for the first
193 * frame. It also looks as if, on output, we first get the
194 * full packet, with a header containing none of the fragmentation
195 * stuff, and then get the frames.
197 * On Linux, we get only reassembled packets, and the exception
198 * frame stuff is hidden - there's a split flag and sequence
199 * number, but it appears that it will never have the exception
202 * XXX - what about OpenBSD? And, for that matter, what about
203 * Windows? (I suspect Windows supplies reassembled frames,
204 * as WinPcap, like PF_PACKET sockets, taps into the networking
205 * stack just as other protocols do.)
207 split_flag = tvb_get_guint8 (tvb, offset);
208 if (has_exception && split_flag == 0xff) {
209 /* This is an exception packet. The flag value there is the
210 "this is an exception flag" packet; the next two bytes
211 after it are padding. */
212 proto_tree_add_uint (arcnet_tree, hf_arcnet_exception_flag, tvb, offset, 1,
216 proto_tree_add_text (arcnet_tree, tvb, offset, 2, "Padding");
219 /* Another copy of the packet type appears after the padding. */
220 proto_tree_add_item (arcnet_tree, hf_arcnet_protID, tvb, offset, 1, ENC_BIG_ENDIAN);
223 /* And after that comes the real split flag. */
224 split_flag = tvb_get_guint8 (tvb, offset);
227 proto_tree_add_uint (arcnet_tree, hf_arcnet_split_flag, tvb, offset, 1,
231 proto_tree_add_item (arcnet_tree, hf_arcnet_sequence, tvb, offset, 2, ENC_BIG_ENDIAN);
237 /* Set the length of the ARCNET header protocol tree item. */
238 proto_item_set_len(ti, offset);
240 next_tvb = tvb_new_subset_remaining (tvb, offset);
242 if (!dissector_try_uint (arcnet_dissector_table, protID,
243 next_tvb, pinfo, tree))
245 col_add_fstr (pinfo->cinfo, COL_PROTOCOL, "0x%04x", protID);
246 call_dissector (data_handle, next_tvb, pinfo, tree);
252 * BSD-style ARCNET headers - they don't have the offset field from the
253 * ARCNET hardware packet, but we might get an exception frame header.
256 dissect_arcnet (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
258 dissect_arcnet_common (tvb, pinfo, tree, FALSE, TRUE);
262 * Linux-style ARCNET headers - they *do* have the offset field from the
263 * ARCNET hardware packet, but we should never see an exception frame
267 dissect_arcnet_linux (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
269 dissect_arcnet_common (tvb, pinfo, tree, TRUE, ENC_BIG_ENDIAN);
272 static const value_string arcnet_prot_id_vals[] = {
273 {ARCNET_PROTO_IP_1051, "RFC 1051 IP"},
274 {ARCNET_PROTO_ARP_1051, "RFC 1051 ARP"},
275 {ARCNET_PROTO_IP_1201, "RFC 1201 IP"},
276 {ARCNET_PROTO_ARP_1201, "RFC 1201 ARP"},
277 {ARCNET_PROTO_RARP_1201, "RFC 1201 RARP"},
278 {ARCNET_PROTO_IPX, "IPX"},
279 {ARCNET_PROTO_NOVELL_EC, "Novell of some sort"},
280 {ARCNET_PROTO_IPv6, "IPv6"},
281 {ARCNET_PROTO_ETHERNET, "Encapsulated Ethernet"},
282 {ARCNET_PROTO_DATAPOINT_BOOT, "Datapoint boot"},
283 {ARCNET_PROTO_DATAPOINT_MOUNT, "Datapoint mount"},
284 {ARCNET_PROTO_POWERLAN_BEACON, "PowerLAN beacon"},
285 {ARCNET_PROTO_POWERLAN_BEACON2, "PowerLAN beacon2"},
286 {ARCNET_PROTO_APPLETALK, "Appletalk"},
287 {ARCNET_PROTO_BANYAN, "Banyan VINES"},
288 {ARCNET_PROTO_DIAGNOSE, "Diagnose"},
289 {ARCNET_PROTO_BACNET, "BACnet"},
294 proto_register_arcnet (void)
297 /* Setup list of header fields See Section 1.6.1 for details*/
298 static hf_register_info hf[] = {
300 {"Source", "arcnet.src",
301 FT_UINT8, BASE_HEX, NULL, 0,
305 {"Dest", "arcnet.dst",
306 FT_UINT8, BASE_HEX, NULL, 0,
310 {"Offset", "arcnet.offset",
311 FT_BYTES, BASE_NONE, NULL, 0,
315 {"Protocol ID", "arcnet.protID",
316 FT_UINT8, BASE_HEX, VALS(arcnet_prot_id_vals), 0,
319 {&hf_arcnet_split_flag,
320 {"Split Flag", "arcnet.split_flag",
321 FT_UINT8, BASE_DEC, NULL, 0,
324 {&hf_arcnet_exception_flag,
325 {"Exception Flag", "arcnet.exception_flag",
326 FT_UINT8, BASE_HEX, NULL, 0,
329 {&hf_arcnet_sequence,
330 {"Sequence", "arcnet.sequence",
331 FT_UINT16, BASE_DEC, NULL, 0,
332 "Sequence number", HFILL}
336 /* Setup protocol subtree array */
337 static gint *ett[] = {
341 arcnet_dissector_table = register_dissector_table ("arcnet.protocol_id",
342 "ARCNET Protocol ID",
345 /* Register the protocol name and description */
346 proto_arcnet = proto_register_protocol ("ARCNET", "ARCNET", "arcnet");
348 /* Required function calls to register the header fields and subtrees used */
349 proto_register_field_array (proto_arcnet, hf, array_length (hf));
350 proto_register_subtree_array (ett, array_length (ett));
355 proto_reg_handoff_arcnet (void)
357 dissector_handle_t arcnet_handle, arcnet_linux_handle;
359 arcnet_handle = create_dissector_handle (dissect_arcnet, proto_arcnet);
360 dissector_add_uint ("wtap_encap", WTAP_ENCAP_ARCNET, arcnet_handle);
362 arcnet_linux_handle = create_dissector_handle (dissect_arcnet_linux,
364 dissector_add_uint ("wtap_encap", WTAP_ENCAP_ARCNET_LINUX, arcnet_linux_handle);
365 data_handle = find_dissector ("data");