2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
25 static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/tcpdump/print-arp.c,v 1.64 2004/04/30 16:42:14 mcr Exp $ (LBL)";
33 #include <tcpdump-stdinc.h>
38 #include "netdissect.h"
39 #include "addrtoname.h"
41 #include "ethertype.h"
42 #include "extract.h" /* must come after interface.h */
45 * Address Resolution Protocol.
47 * See RFC 826 for protocol description. ARP packets are variable
48 * in size; the arphdr structure defines the fixed-length portion.
49 * Protocol type values are the same as those for 10 Mb/s Ethernet.
50 * It is followed by the variable-sized fields ar_sha, arp_spa,
51 * arp_tha and arp_tpa in that order, according to the lengths
52 * specified. Field names used correspond to RFC 826.
55 u_short ar_hrd; /* format of hardware address */
56 #define ARPHRD_ETHER 1 /* ethernet hardware format */
57 #define ARPHRD_IEEE802 6 /* token-ring hardware format */
58 #define ARPHRD_ARCNET 7 /* arcnet hardware format */
59 #define ARPHRD_FRELAY 15 /* frame relay hardware format */
60 #define ARPHRD_STRIP 23 /* Ricochet Starmode Radio hardware format */
61 #define ARPHRD_IEEE1394 24 /* IEEE 1394 (FireWire) hardware format */
62 u_short ar_pro; /* format of protocol address */
63 u_char ar_hln; /* length of hardware address */
64 u_char ar_pln; /* length of protocol address */
65 u_short ar_op; /* one of: */
66 #define ARPOP_REQUEST 1 /* request to resolve address */
67 #define ARPOP_REPLY 2 /* response to previous request */
68 #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */
69 #define ARPOP_REVREPLY 4 /* response giving protocol address */
70 #define ARPOP_INVREQUEST 8 /* request to identify peer */
71 #define ARPOP_INVREPLY 9 /* response identifying peer */
73 * The remaining fields are variable in size,
74 * according to the sizes above.
77 u_char ar_sha[]; /* sender hardware address */
78 u_char ar_spa[]; /* sender protocol address */
79 u_char ar_tha[]; /* target hardware address */
80 u_char ar_tpa[]; /* target protocol address */
82 #define ar_sha(ap) (((const u_char *)((ap)+1))+0)
83 #define ar_spa(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln)
84 #define ar_tha(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln+(ap)->ar_pln)
85 #define ar_tpa(ap) (((const u_char *)((ap)+1))+2*(ap)->ar_hln+(ap)->ar_pln)
90 #define HRD(ap) EXTRACT_16BITS(&(ap)->ar_hrd)
91 #define HLN(ap) ((ap)->ar_hln)
92 #define PLN(ap) ((ap)->ar_pln)
93 #define OP(ap) EXTRACT_16BITS(&(ap)->ar_op)
94 #define PRO(ap) EXTRACT_16BITS(&(ap)->ar_pro)
95 #define SHA(ap) (ar_sha(ap))
96 #define SPA(ap) (ar_spa(ap))
97 #define THA(ap) (ar_tha(ap))
98 #define TPA(ap) (ar_tpa(ap))
101 * ATM Address Resolution Protocol.
103 * See RFC 2225 for protocol description. ATMARP packets are similar
104 * to ARP packets, except that there are no length fields for the
105 * protocol address - instead, there are type/length fields for
106 * the ATM number and subaddress - and the hardware addresses consist
107 * of an ATM number and an ATM subaddress.
109 struct atmarp_pkthdr {
110 u_short aar_hrd; /* format of hardware address */
111 #define ARPHRD_ATM2225 19 /* ATM (RFC 2225) */
112 u_short aar_pro; /* format of protocol address */
113 u_char aar_shtl; /* length of source ATM number */
114 u_char aar_sstl; /* length of source ATM subaddress */
115 #define ATMARP_IS_E164 0x40 /* bit in type/length for E.164 format */
116 #define ATMARP_LEN_MASK 0x3F /* length of {sub}address in type/length */
117 u_short aar_op; /* same as regular ARP */
118 #define ATMARPOP_NAK 10 /* NAK */
119 u_char aar_spln; /* length of source protocol address */
120 u_char aar_thtl; /* length of target ATM number */
121 u_char aar_tstl; /* length of target ATM subaddress */
122 u_char aar_tpln; /* length of target protocol address */
124 * The remaining fields are variable in size,
125 * according to the sizes above.
128 u_char aar_sha[]; /* source ATM number */
129 u_char aar_ssa[]; /* source ATM subaddress */
130 u_char aar_spa[]; /* sender protocol address */
131 u_char aar_tha[]; /* target ATM number */
132 u_char aar_tsa[]; /* target ATM subaddress */
133 u_char aar_tpa[]; /* target protocol address */
136 #define ATMHRD(ap) EXTRACT_16BITS(&(ap)->aar_hrd)
137 #define ATMSHLN(ap) ((ap)->aar_shtl & ATMARP_LEN_MASK)
138 #define ATMSSLN(ap) ((ap)->aar_sstl & ATMARP_LEN_MASK)
139 #define ATMSPLN(ap) ((ap)->aar_spln)
140 #define ATMOP(ap) EXTRACT_16BITS(&(ap)->aar_op)
141 #define ATMPRO(ap) EXTRACT_16BITS(&(ap)->aar_pro)
142 #define ATMTHLN(ap) ((ap)->aar_thtl & ATMARP_LEN_MASK)
143 #define ATMTSLN(ap) ((ap)->aar_tstl & ATMARP_LEN_MASK)
144 #define ATMTPLN(ap) ((ap)->aar_tpln)
145 #define aar_sha(ap) ((const u_char *)((ap)+1))
146 #define aar_ssa(ap) (aar_sha(ap) + ATMSHLN(ap))
147 #define aar_spa(ap) (aar_ssa(ap) + ATMSSLN(ap))
148 #define aar_tha(ap) (aar_spa(ap) + ATMSPLN(ap))
149 #define aar_tsa(ap) (aar_tha(ap) + ATMTHLN(ap))
150 #define aar_tpa(ap) (aar_tsa(ap) + ATMTSLN(ap))
153 #define ATMSHA(ap) (aar_sha(ap))
154 #define ATMSSA(ap) (aar_ssa(ap))
155 #define ATMSPA(ap) (aar_spa(ap))
156 #define ATMTHA(ap) (aar_tha(ap))
157 #define ATMTSA(ap) (aar_tsa(ap))
158 #define ATMTPA(ap) (aar_tpa(ap))
160 static u_char ezero[6];
163 atmarp_addr_print(netdissect_options *ndo,
164 const u_char *ha, u_int ha_len, const u_char *srca,
168 ND_PRINT((ndo, "<No address>"));
170 ND_PRINT((ndo, "%s", linkaddr_string(ha, ha_len)));
172 ND_PRINT((ndo, ",%s",
173 linkaddr_string(srca, srca_len)));
178 atmarp_print(netdissect_options *ndo,
179 const u_char *bp, u_int length, u_int caplen)
181 const struct atmarp_pkthdr *ap;
182 u_short pro, hrd, op;
184 ap = (const struct atmarp_pkthdr *)bp;
191 if (!ND_TTEST2(*aar_tpa(ap), ATMTPLN(ap))) {
192 ND_PRINT((ndo, "truncated-atmarp"));
193 ND_DEFAULTPRINT((const u_char *)ap, length);
197 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) ||
198 ATMSPLN(ap) != 4 || ATMTPLN(ap) != 4) {
199 ND_PRINT((ndo, "atmarp-#%d for proto #%d (%d/%d) hardware #%d",
200 op, pro, ATMSPLN(ap), ATMTPLN(ap), hrd));
203 if (pro == ETHERTYPE_TRAIL)
204 ND_PRINT((ndo, "trailer-"));
208 ND_PRINT((ndo, "arp who-has %s", ipaddr_string(ATMTPA(ap))));
209 if (ATMTHLN(ap) != 0) {
210 ND_PRINT((ndo, " ("));
211 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHLN(ap),
212 ATMTSA(ap), ATMTSLN(ap));
213 ND_PRINT((ndo, ")"));
215 ND_PRINT((ndo, " tell %s", ipaddr_string(ATMSPA(ap))));
219 ND_PRINT((ndo, "arp reply %s", ipaddr_string(ATMSPA(ap))));
220 ND_PRINT((ndo, " is-at "));
221 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHLN(ap), ATMSSA(ap),
225 case ARPOP_INVREQUEST:
226 ND_PRINT((ndo, "invarp who-is "));
227 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHLN(ap), ATMTSA(ap),
229 ND_PRINT((ndo, " tell "));
230 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHLN(ap), ATMSSA(ap),
235 ND_PRINT((ndo, "invarp reply "));
236 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHLN(ap), ATMSSA(ap),
238 ND_PRINT((ndo, " at %s", ipaddr_string(ATMSPA(ap))));
242 ND_PRINT((ndo, "nak reply for %s",
243 ipaddr_string(ATMSPA(ap))));
247 ND_PRINT((ndo, "atmarp-#%d", op));
248 ND_DEFAULTPRINT((const u_char *)ap, caplen);
253 ND_PRINT((ndo, "[|atmarp]"));
257 arp_print(netdissect_options *ndo,
258 const u_char *bp, u_int length, u_int caplen)
260 const struct arp_pkthdr *ap;
261 u_short pro, hrd, op;
263 ap = (const struct arp_pkthdr *)bp;
266 if (hrd == ARPHRD_ATM2225) {
267 atmarp_print(ndo, bp, length, caplen);
273 if (!ND_TTEST2(*ar_tpa(ap), PLN(ap))) {
274 ND_PRINT((ndo, "truncated-arp"));
275 ND_DEFAULTPRINT((const u_char *)ap, length);
279 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) ||
280 PLN(ap) != 4 || HLN(ap) == 0) {
281 ND_PRINT((ndo, "arp-#%d for proto #%d (%d) hardware #%d (%d)",
282 op, pro, PLN(ap), hrd, HLN(ap)));
285 if (pro == ETHERTYPE_TRAIL)
286 ND_PRINT((ndo, "trailer-"));
290 ND_PRINT((ndo, "arp who-has %s", ipaddr_string(TPA(ap))));
291 if (memcmp((const char *)ezero, (const char *)THA(ap), HLN(ap)) != 0)
292 ND_PRINT((ndo, " (%s)",
293 linkaddr_string(THA(ap), HLN(ap))));
294 ND_PRINT((ndo, " tell %s", ipaddr_string(SPA(ap))));
298 ND_PRINT((ndo, "arp reply %s", ipaddr_string(SPA(ap))));
299 ND_PRINT((ndo, " is-at %s", linkaddr_string(SHA(ap), HLN(ap))));
302 case ARPOP_REVREQUEST:
303 ND_PRINT((ndo, "rarp who-is %s tell %s",
304 linkaddr_string(THA(ap), HLN(ap)),
305 linkaddr_string(SHA(ap), HLN(ap))));
309 ND_PRINT((ndo, "rarp reply %s at %s",
310 linkaddr_string(THA(ap), HLN(ap)),
311 ipaddr_string(TPA(ap))));
314 case ARPOP_INVREQUEST:
315 ND_PRINT((ndo, "invarp who-is %s tell %s",
316 linkaddr_string(THA(ap), HLN(ap)),
317 linkaddr_string(SHA(ap), HLN(ap))));
321 ND_PRINT((ndo,"invarp reply %s at %s",
322 linkaddr_string(THA(ap), HLN(ap)),
323 ipaddr_string(TPA(ap))));
327 ND_PRINT((ndo, "arp-#%d", op));
328 ND_DEFAULTPRINT((const u_char *)ap, caplen);
331 if (hrd != ARPHRD_ETHER)
332 ND_PRINT((ndo, " hardware #%d", hrd));
335 ND_PRINT((ndo, "[|arp]"));