2 * Routines for Appletalk ARP packet disassembly
4 * $Id: packet-aarp.c,v 1.37 2002/08/28 21:00:06 jmayer Exp $
6 * Simon Wilkinson <sxw@dcs.ed.ac.uk>
8 * Ethereal - Network traffic analyzer
9 * By Gerald Combs <gerald@ethereal.com>
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
33 #include <epan/packet.h>
34 #include <epan/strutil.h>
37 static int proto_aarp = -1;
38 static int hf_aarp_hard_type = -1;
39 static int hf_aarp_proto_type = -1;
40 static int hf_aarp_hard_size = -1;
41 static int hf_aarp_proto_size = -1;
42 static int hf_aarp_opcode = -1;
43 static int hf_aarp_src_hw = -1;
44 static int hf_aarp_src_hw_mac = -1;
45 static int hf_aarp_src_proto = -1;
46 static int hf_aarp_src_proto_id = -1;
47 static int hf_aarp_dst_hw = -1;
48 static int hf_aarp_dst_hw_mac = -1;
49 static int hf_aarp_dst_proto = -1;
50 static int hf_aarp_dst_proto_id = -1;
52 static gint ett_aarp = -1;
55 #define AARP_REQUEST 0x0001
58 #define AARP_REPLY 0x0002
61 #define AARP_PROBE 0x0003
64 /* The following is screwed up shit to deal with the fact that
65 the linux kernel edits the packet inline. */
66 #define AARP_REQUEST_SWAPPED 0x0100
67 #define AARP_REPLY_SWAPPED 0x0200
68 #define AARP_PROBE_SWAPPED 0x0300
70 static const value_string op_vals[] = {
71 {AARP_REQUEST, "request" },
72 {AARP_REPLY, "reply" },
73 {AARP_PROBE, "probe" },
74 {AARP_REQUEST_SWAPPED, "request" },
75 {AARP_REPLY_SWAPPED, "reply" },
76 {AARP_PROBE_SWAPPED, "probe" },
79 /* AARP protocol HARDWARE identifiers. */
80 #define AARPHRD_ETHER 1 /* Ethernet 10Mbps */
81 #define AARPHRD_TR 2 /* Token Ring */
83 static const value_string hrd_vals[] = {
84 {AARPHRD_ETHER, "Ethernet" },
85 {AARPHRD_TR, "Token Ring" },
89 * Given the hardware address type and length, check whether an address
90 * is an Ethernet address - the address must be of type "Ethernet" or
91 * "Token Ring", and the length must be 6 bytes.
93 #define AARP_HW_IS_ETHER(ar_hrd, ar_hln) \
94 (((ar_hrd) == AARPHRD_ETHER || (ar_hrd) == AARPHRD_TR) \
98 * Given the protocol address type and length, check whether an address
99 * is an Appletalk address - the address must be of type "Appletalk",
100 * and the length must be 4 bytes.
102 #define AARP_PRO_IS_ATALK(ar_pro, ar_pln) \
103 ((ar_pro) == ETHERTYPE_ATALK && (ar_pln) == 4)
106 atalkid_to_str(const guint8 *ad) {
108 static gchar str[3][16];
111 if (cur == &str[0][0]) {
113 } else if (cur == &str[1][0]) {
120 sprintf(cur, "%d.%d",node,ad[3]);
125 aarphrdaddr_to_str(const guint8 *ad, int ad_len, guint16 type) {
126 if (AARP_HW_IS_ETHER(type, ad_len)) {
127 /* Ethernet address (or Token Ring address, which is the same type
129 return ether_to_str(ad);
131 return bytes_to_str(ad, ad_len);
135 aarpproaddr_to_str(const guint8 *ad, int ad_len, guint16 type) {
136 if (AARP_PRO_IS_ATALK(type, ad_len)) {
137 /* Appletalk address. */
138 return atalkid_to_str(ad);
140 return bytes_to_str(ad, ad_len);
143 /* Offsets of fields within an AARP packet. */
149 #define MIN_AARP_HEADER_SIZE 8
152 dissect_aarp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) {
158 proto_tree *aarp_tree;
161 int sha_offset, spa_offset, tha_offset, tpa_offset;
162 const guint8 *sha_val, *spa_val, *tha_val, *tpa_val;
163 gchar *sha_str, *spa_str, *tha_str, *tpa_str;
165 if(check_col(pinfo->cinfo, COL_PROTOCOL))
166 col_set_str(pinfo->cinfo, COL_PROTOCOL, "AARP");
167 if(check_col(pinfo->cinfo, COL_INFO))
168 col_clear(pinfo->cinfo, COL_INFO);
170 ar_hrd = tvb_get_ntohs(tvb, AR_HRD);
171 ar_pro = tvb_get_ntohs(tvb, AR_PRO);
172 ar_hln = tvb_get_guint8(tvb, AR_HLN);
173 ar_pln = tvb_get_guint8(tvb, AR_PLN);
174 ar_op = tvb_get_ntohs(tvb, AR_OP);
176 /* Get the offsets of the addresses. */
177 sha_offset = MIN_AARP_HEADER_SIZE;
178 spa_offset = sha_offset + ar_hln;
179 tha_offset = spa_offset + ar_pln;
180 tpa_offset = tha_offset + ar_hln;
182 /* Extract the addresses. */
183 sha_val = tvb_get_ptr(tvb, sha_offset, ar_hln);
184 sha_str = aarphrdaddr_to_str(sha_val, ar_hln, ar_hrd);
186 spa_val = tvb_get_ptr(tvb, spa_offset, ar_pln);
187 spa_str = aarpproaddr_to_str(spa_val, ar_pln, ar_pro);
189 tha_val = tvb_get_ptr(tvb, tha_offset, ar_hln);
190 tha_str = aarphrdaddr_to_str(tha_val, ar_hln, ar_hrd);
192 tpa_val = tvb_get_ptr(tvb, tpa_offset, ar_pln);
193 tpa_str = aarpproaddr_to_str(tpa_val, ar_pln, ar_pro);
195 if (check_col(pinfo->cinfo, COL_INFO)) {
198 case AARP_REQUEST_SWAPPED:
199 col_add_fstr(pinfo->cinfo, COL_INFO, "Who has %s? Tell %s", tpa_str, spa_str);
202 case AARP_REPLY_SWAPPED:
203 col_add_fstr(pinfo->cinfo, COL_INFO, "%s is at %s", spa_str, sha_str);
206 case AARP_PROBE_SWAPPED:
207 col_add_fstr(pinfo->cinfo, COL_INFO, "Is there a %s", tpa_str);
210 col_add_fstr(pinfo->cinfo, COL_INFO, "Unknown AARP opcode 0x%04x", ar_op);
216 if ((op_str = match_strval(ar_op, op_vals)))
217 ti = proto_tree_add_protocol_format(tree, proto_aarp, tvb, 0,
218 MIN_AARP_HEADER_SIZE + 2*ar_hln +
219 2*ar_pln, "AppleTalk Address Resolution Protocol (%s)", op_str);
221 ti = proto_tree_add_protocol_format(tree, proto_aarp, tvb, 0,
222 MIN_AARP_HEADER_SIZE + 2*ar_hln +
224 "AppleTalk Address Resolution Protocol (opcode 0x%04x)", ar_op);
225 aarp_tree = proto_item_add_subtree(ti, ett_aarp);
226 proto_tree_add_uint(aarp_tree, hf_aarp_hard_type, tvb, AR_HRD, 2,
228 proto_tree_add_uint(aarp_tree, hf_aarp_proto_type, tvb, AR_PRO, 2,
230 proto_tree_add_uint(aarp_tree, hf_aarp_hard_size, tvb, AR_HLN, 1,
232 proto_tree_add_uint(aarp_tree, hf_aarp_proto_size, tvb, AR_PLN, 1,
234 proto_tree_add_uint(aarp_tree, hf_aarp_opcode, tvb, AR_OP, 2,
237 proto_tree_add_item(aarp_tree,
238 AARP_HW_IS_ETHER(ar_hrd, ar_hln) ? hf_aarp_src_hw_mac : hf_aarp_src_hw,
239 tvb, sha_offset, ar_hln, FALSE);
243 if (AARP_PRO_IS_ATALK(ar_pro, ar_pln)) {
244 proto_tree_add_bytes_format(aarp_tree, hf_aarp_src_proto_id, tvb, spa_offset, ar_pln,
246 "Sender ID: %s", spa_str);
248 proto_tree_add_bytes_format(aarp_tree, hf_aarp_src_proto, tvb, spa_offset, ar_pln,
250 "Sender protocol address: %s", spa_str);
255 proto_tree_add_item(aarp_tree,
256 AARP_HW_IS_ETHER(ar_hrd, ar_hln) ? hf_aarp_dst_hw_mac : hf_aarp_dst_hw,
257 tvb, tha_offset, ar_hln, FALSE);
261 if (AARP_PRO_IS_ATALK(ar_pro, ar_pln)) {
262 proto_tree_add_bytes_format(aarp_tree, hf_aarp_dst_proto_id, tvb, tpa_offset, ar_pln,
264 "Target ID: %s", tpa_str);
266 proto_tree_add_bytes_format(aarp_tree, hf_aarp_dst_proto, tvb, tpa_offset, ar_pln,
268 "Target protocol address: %s", tpa_str);
275 proto_register_aarp(void)
277 static hf_register_info hf[] = {
278 { &hf_aarp_hard_type,
279 { "Hardware type", "aarp.hard.type",
280 FT_UINT16, BASE_HEX, VALS(hrd_vals), 0x0,
283 { &hf_aarp_proto_type,
284 { "Protocol type", "aarp.proto.type",
285 FT_UINT16, BASE_HEX, VALS(etype_vals), 0x0,
288 { &hf_aarp_hard_size,
289 { "Hardware size", "aarp.hard.size",
290 FT_UINT8, BASE_DEC, NULL, 0x0,
293 { &hf_aarp_proto_size,
294 { "Protocol size", "aarp.proto.size",
295 FT_UINT8, BASE_DEC, NULL, 0x0,
299 { "Opcode", "aarp.opcode",
300 FT_UINT16, BASE_DEC, VALS(op_vals), 0x0,
304 { "Sender hardware address", "aarp.src.hw",
305 FT_BYTES, BASE_NONE, NULL, 0x0,
308 { &hf_aarp_src_hw_mac,
309 { "Sender MAC address", "aarp.src.hw_mac",
310 FT_ETHER, BASE_NONE, NULL, 0x0,
313 { &hf_aarp_src_proto,
314 { "Sender protocol address", "aarp.src.proto",
315 FT_BYTES, BASE_NONE, NULL, 0x0,
318 { &hf_aarp_src_proto_id,
319 { "Sender ID", "aarp.src.proto_id",
320 FT_BYTES, BASE_HEX, NULL, 0x0,
324 { "Target hardware address", "aarp.dst.hw",
325 FT_BYTES, BASE_NONE, NULL, 0x0,
328 { &hf_aarp_dst_hw_mac,
329 { "Target MAC address", "aarp.dst.hw_mac",
330 FT_ETHER, BASE_NONE, NULL, 0x0,
333 { &hf_aarp_dst_proto,
334 { "Target protocol address", "aarp.dst.proto",
335 FT_BYTES, BASE_NONE, NULL, 0x0,
338 { &hf_aarp_dst_proto_id,
339 { "Target ID", "aarp.dst.proto_id",
340 FT_BYTES, BASE_HEX, NULL, 0x0,
343 static gint *ett[] = {
347 proto_aarp = proto_register_protocol("Appletalk Address Resolution Protocol",
350 proto_register_field_array(proto_aarp, hf, array_length(hf));
351 proto_register_subtree_array(ett, array_length(ett));
355 proto_reg_handoff_aarp(void)
357 dissector_handle_t aarp_handle;
359 aarp_handle = create_dissector_handle(dissect_aarp, proto_aarp);
360 dissector_add("ethertype", ETHERTYPE_AARP, aarp_handle);
361 dissector_add("chdlctype", ETHERTYPE_AARP, aarp_handle);