2 * Routines for Appletalk ARP packet disassembly
6 * Simon Wilkinson <sxw@dcs.ed.ac.uk>
8 * Wireshark - Network traffic analyzer
9 * By Gerald Combs <gerald@wireshark.org>
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>
35 #include <epan/emem.h>
36 #include <epan/etypes.h>
38 static int proto_aarp = -1;
39 static int hf_aarp_hard_type = -1;
40 static int hf_aarp_proto_type = -1;
41 static int hf_aarp_hard_size = -1;
42 static int hf_aarp_proto_size = -1;
43 static int hf_aarp_opcode = -1;
44 static int hf_aarp_src_hw = -1;
45 static int hf_aarp_src_hw_mac = -1;
46 static int hf_aarp_src_proto = -1;
47 static int hf_aarp_src_proto_id = -1;
48 static int hf_aarp_dst_hw = -1;
49 static int hf_aarp_dst_hw_mac = -1;
50 static int hf_aarp_dst_proto = -1;
51 static int hf_aarp_dst_proto_id = -1;
53 static gint ett_aarp = -1;
56 #define AARP_REQUEST 0x0001
59 #define AARP_REPLY 0x0002
62 #define AARP_PROBE 0x0003
65 /* The following is screwed up shit to deal with the fact that
66 the linux kernel edits the packet inline. */
67 #define AARP_REQUEST_SWAPPED 0x0100
68 #define AARP_REPLY_SWAPPED 0x0200
69 #define AARP_PROBE_SWAPPED 0x0300
71 static const value_string op_vals[] = {
72 {AARP_REQUEST, "request" },
73 {AARP_REPLY, "reply" },
74 {AARP_PROBE, "probe" },
75 {AARP_REQUEST_SWAPPED, "request" },
76 {AARP_REPLY_SWAPPED, "reply" },
77 {AARP_PROBE_SWAPPED, "probe" },
80 /* AARP protocol HARDWARE identifiers. */
81 #define AARPHRD_ETHER 1 /* Ethernet 10Mbps */
82 #define AARPHRD_TR 2 /* Token Ring */
84 static const value_string hrd_vals[] = {
85 {AARPHRD_ETHER, "Ethernet" },
86 {AARPHRD_TR, "Token Ring" },
90 * Given the hardware address type and length, check whether an address
91 * is an Ethernet address - the address must be of type "Ethernet" or
92 * "Token Ring", and the length must be 6 bytes.
94 #define AARP_HW_IS_ETHER(ar_hrd, ar_hln) \
95 (((ar_hrd) == AARPHRD_ETHER || (ar_hrd) == AARPHRD_TR) \
99 * Given the protocol address type and length, check whether an address
100 * is an Appletalk address - the address must be of type "Appletalk",
101 * and the length must be 4 bytes.
103 #define AARP_PRO_IS_ATALK(ar_pro, ar_pln) \
104 ((ar_pro) == ETHERTYPE_ATALK && (ar_pln) == 4)
107 atalkid_to_str(const guint8 *ad) {
113 g_snprintf(cur, 16, "%d.%d",node,ad[3]);
118 aarphrdaddr_to_str(const guint8 *ad, int ad_len, guint16 type) {
119 if (AARP_HW_IS_ETHER(type, ad_len)) {
120 /* Ethernet address (or Token Ring address, which is the same type
122 return ether_to_str(ad);
124 return bytes_to_str(ad, ad_len);
128 aarpproaddr_to_str(const guint8 *ad, int ad_len, guint16 type) {
129 if (AARP_PRO_IS_ATALK(type, ad_len)) {
130 /* Appletalk address. */
131 return atalkid_to_str(ad);
133 return bytes_to_str(ad, ad_len);
136 /* Offsets of fields within an AARP packet. */
142 #define MIN_AARP_HEADER_SIZE 8
145 dissect_aarp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) {
151 proto_tree *aarp_tree;
154 int sha_offset, spa_offset, tha_offset, tpa_offset;
155 const guint8 *sha_val, *spa_val, *tha_val, *tpa_val;
156 gchar *sha_str, *spa_str, *tha_str, *tpa_str;
158 if(check_col(pinfo->cinfo, COL_PROTOCOL))
159 col_set_str(pinfo->cinfo, COL_PROTOCOL, "AARP");
160 if(check_col(pinfo->cinfo, COL_INFO))
161 col_clear(pinfo->cinfo, COL_INFO);
163 ar_hrd = tvb_get_ntohs(tvb, AR_HRD);
164 ar_pro = tvb_get_ntohs(tvb, AR_PRO);
165 ar_hln = tvb_get_guint8(tvb, AR_HLN);
166 ar_pln = tvb_get_guint8(tvb, AR_PLN);
167 ar_op = tvb_get_ntohs(tvb, AR_OP);
169 /* Get the offsets of the addresses. */
170 sha_offset = MIN_AARP_HEADER_SIZE;
171 spa_offset = sha_offset + ar_hln;
172 tha_offset = spa_offset + ar_pln;
173 tpa_offset = tha_offset + ar_hln;
175 /* Extract the addresses. */
176 sha_val = tvb_get_ptr(tvb, sha_offset, ar_hln);
177 sha_str = aarphrdaddr_to_str(sha_val, ar_hln, ar_hrd);
179 spa_val = tvb_get_ptr(tvb, spa_offset, ar_pln);
180 spa_str = aarpproaddr_to_str(spa_val, ar_pln, ar_pro);
182 tha_val = tvb_get_ptr(tvb, tha_offset, ar_hln);
183 tha_str = aarphrdaddr_to_str(tha_val, ar_hln, ar_hrd);
185 tpa_val = tvb_get_ptr(tvb, tpa_offset, ar_pln);
186 tpa_str = aarpproaddr_to_str(tpa_val, ar_pln, ar_pro);
188 if (check_col(pinfo->cinfo, COL_INFO)) {
191 case AARP_REQUEST_SWAPPED:
192 col_add_fstr(pinfo->cinfo, COL_INFO, "Who has %s? Tell %s", tpa_str, spa_str);
195 case AARP_REPLY_SWAPPED:
196 col_add_fstr(pinfo->cinfo, COL_INFO, "%s is at %s", spa_str, sha_str);
199 case AARP_PROBE_SWAPPED:
200 col_add_fstr(pinfo->cinfo, COL_INFO, "Is there a %s", tpa_str);
203 col_add_fstr(pinfo->cinfo, COL_INFO, "Unknown AARP opcode 0x%04x", ar_op);
209 if ((op_str = match_strval(ar_op, op_vals)))
210 ti = proto_tree_add_protocol_format(tree, proto_aarp, tvb, 0,
211 MIN_AARP_HEADER_SIZE + 2*ar_hln +
212 2*ar_pln, "AppleTalk Address Resolution Protocol (%s)", op_str);
214 ti = proto_tree_add_protocol_format(tree, proto_aarp, tvb, 0,
215 MIN_AARP_HEADER_SIZE + 2*ar_hln +
217 "AppleTalk Address Resolution Protocol (opcode 0x%04x)", ar_op);
218 aarp_tree = proto_item_add_subtree(ti, ett_aarp);
219 proto_tree_add_uint(aarp_tree, hf_aarp_hard_type, tvb, AR_HRD, 2,
221 proto_tree_add_uint(aarp_tree, hf_aarp_proto_type, tvb, AR_PRO, 2,
223 proto_tree_add_uint(aarp_tree, hf_aarp_hard_size, tvb, AR_HLN, 1,
225 proto_tree_add_uint(aarp_tree, hf_aarp_proto_size, tvb, AR_PLN, 1,
227 proto_tree_add_uint(aarp_tree, hf_aarp_opcode, tvb, AR_OP, 2,
230 proto_tree_add_item(aarp_tree,
231 AARP_HW_IS_ETHER(ar_hrd, ar_hln) ? hf_aarp_src_hw_mac : hf_aarp_src_hw,
232 tvb, sha_offset, ar_hln, FALSE);
236 if (AARP_PRO_IS_ATALK(ar_pro, ar_pln)) {
237 proto_tree_add_bytes_format_value(aarp_tree, hf_aarp_src_proto_id, tvb,
242 proto_tree_add_bytes_format_value(aarp_tree, hf_aarp_src_proto, tvb,
250 proto_tree_add_item(aarp_tree,
251 AARP_HW_IS_ETHER(ar_hrd, ar_hln) ? hf_aarp_dst_hw_mac : hf_aarp_dst_hw,
252 tvb, tha_offset, ar_hln, FALSE);
256 if (AARP_PRO_IS_ATALK(ar_pro, ar_pln)) {
257 proto_tree_add_bytes_format_value(aarp_tree, hf_aarp_dst_proto_id, tvb,
262 proto_tree_add_bytes_format_value(aarp_tree, hf_aarp_dst_proto, tvb,
272 proto_register_aarp(void)
274 static hf_register_info hf[] = {
275 { &hf_aarp_hard_type,
276 { "Hardware type", "aarp.hard.type",
277 FT_UINT16, BASE_HEX, VALS(hrd_vals), 0x0,
280 { &hf_aarp_proto_type,
281 { "Protocol type", "aarp.proto.type",
282 FT_UINT16, BASE_HEX, VALS(etype_vals), 0x0,
285 { &hf_aarp_hard_size,
286 { "Hardware size", "aarp.hard.size",
287 FT_UINT8, BASE_DEC, NULL, 0x0,
290 { &hf_aarp_proto_size,
291 { "Protocol size", "aarp.proto.size",
292 FT_UINT8, BASE_DEC, NULL, 0x0,
296 { "Opcode", "aarp.opcode",
297 FT_UINT16, BASE_DEC, VALS(op_vals), 0x0,
301 { "Sender hardware address", "aarp.src.hw",
302 FT_BYTES, BASE_NONE, NULL, 0x0,
305 { &hf_aarp_src_hw_mac,
306 { "Sender MAC address", "aarp.src.hw_mac",
307 FT_ETHER, BASE_NONE, NULL, 0x0,
310 { &hf_aarp_src_proto,
311 { "Sender protocol address", "aarp.src.proto",
312 FT_BYTES, BASE_NONE, NULL, 0x0,
315 { &hf_aarp_src_proto_id,
316 { "Sender ID", "aarp.src.proto_id",
317 FT_BYTES, BASE_NONE, NULL, 0x0,
321 { "Target hardware address", "aarp.dst.hw",
322 FT_BYTES, BASE_NONE, NULL, 0x0,
325 { &hf_aarp_dst_hw_mac,
326 { "Target MAC address", "aarp.dst.hw_mac",
327 FT_ETHER, BASE_NONE, NULL, 0x0,
330 { &hf_aarp_dst_proto,
331 { "Target protocol address", "aarp.dst.proto",
332 FT_BYTES, BASE_NONE, NULL, 0x0,
335 { &hf_aarp_dst_proto_id,
336 { "Target ID", "aarp.dst.proto_id",
337 FT_BYTES, BASE_NONE, NULL, 0x0,
340 static gint *ett[] = {
344 proto_aarp = proto_register_protocol("Appletalk Address Resolution Protocol",
347 proto_register_field_array(proto_aarp, hf, array_length(hf));
348 proto_register_subtree_array(ett, array_length(ett));
352 proto_reg_handoff_aarp(void)
354 dissector_handle_t aarp_handle;
356 aarp_handle = create_dissector_handle(dissect_aarp, proto_aarp);
357 dissector_add("ethertype", ETHERTYPE_AARP, aarp_handle);
358 dissector_add("chdlctype", ETHERTYPE_AARP, aarp_handle);