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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.
22 /* \summary: Address Resolution Protocol (ARP) printer */
28 #include "netdissect-stdinc.h"
30 #define ND_LONGJMP_FROM_TCHECK
31 #include "netdissect.h"
32 #include "addrtoname.h"
33 #include "ethertype.h"
38 * Address Resolution Protocol.
40 * See RFC 826 for protocol description. ARP packets are variable
41 * in size; the arphdr structure defines the fixed-length portion.
42 * Protocol type values are the same as those for 10 Mb/s Ethernet.
43 * It is followed by the variable-sized fields ar_sha, arp_spa,
44 * arp_tha and arp_tpa in that order, according to the lengths
45 * specified. Field names used correspond to RFC 826.
48 nd_uint16_t ar_hrd; /* format of hardware address */
49 #define ARPHRD_ETHER 1 /* ethernet hardware format */
50 #define ARPHRD_IEEE802 6 /* token-ring hardware format */
51 #define ARPHRD_ARCNET 7 /* arcnet hardware format */
52 #define ARPHRD_FRELAY 15 /* frame relay hardware format */
53 #define ARPHRD_ATM2225 19 /* ATM (RFC 2225) */
54 #define ARPHRD_STRIP 23 /* Ricochet Starmode Radio hardware format */
55 #define ARPHRD_IEEE1394 24 /* IEEE 1394 (FireWire) hardware format */
56 #define ARPHRD_INFINIBAND 32 /* InfiniBand RFC 4391 */
57 nd_uint16_t ar_pro; /* format of protocol address */
58 nd_uint8_t ar_hln; /* length of hardware address */
59 nd_uint8_t ar_pln; /* length of protocol address */
60 nd_uint16_t ar_op; /* one of: */
61 #define ARPOP_REQUEST 1 /* request to resolve address */
62 #define ARPOP_REPLY 2 /* response to previous request */
63 #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */
64 #define ARPOP_REVREPLY 4 /* response giving protocol address */
65 #define ARPOP_INVREQUEST 8 /* request to identify peer */
66 #define ARPOP_INVREPLY 9 /* response identifying peer */
67 #define ARPOP_NAK 10 /* NAK - only valif for ATM ARP */
70 * The remaining fields are variable in size,
71 * according to the sizes above.
74 nd_byte ar_sha[]; /* sender hardware address */
75 nd_byte ar_spa[]; /* sender protocol address */
76 nd_byte ar_tha[]; /* target hardware address */
77 nd_byte ar_tpa[]; /* target protocol address */
79 #define ar_sha(ap) (((const u_char *)((ap)+1))+ 0)
80 #define ar_spa(ap) (((const u_char *)((ap)+1))+ GET_U_1((ap)->ar_hln))
81 #define ar_tha(ap) (((const u_char *)((ap)+1))+ GET_U_1((ap)->ar_hln)+GET_U_1((ap)->ar_pln))
82 #define ar_tpa(ap) (((const u_char *)((ap)+1))+2*GET_U_1((ap)->ar_hln)+GET_U_1((ap)->ar_pln))
87 #define HRD(ap) GET_BE_U_2((ap)->ar_hrd)
88 #define HRD_LEN(ap) GET_U_1((ap)->ar_hln)
89 #define PROTO_LEN(ap) GET_U_1((ap)->ar_pln)
90 #define OP(ap) GET_BE_U_2((ap)->ar_op)
91 #define PRO(ap) GET_BE_U_2((ap)->ar_pro)
92 #define SHA(ap) (ar_sha(ap))
93 #define SPA(ap) (ar_spa(ap))
94 #define THA(ap) (ar_tha(ap))
95 #define TPA(ap) (ar_tpa(ap))
98 static const struct tok arpop_values[] = {
99 { ARPOP_REQUEST, "Request" },
100 { ARPOP_REPLY, "Reply" },
101 { ARPOP_REVREQUEST, "Reverse Request" },
102 { ARPOP_REVREPLY, "Reverse Reply" },
103 { ARPOP_INVREQUEST, "Inverse Request" },
104 { ARPOP_INVREPLY, "Inverse Reply" },
105 { ARPOP_NAK, "NACK Reply" },
109 static const struct tok arphrd_values[] = {
110 { ARPHRD_ETHER, "Ethernet" },
111 { ARPHRD_IEEE802, "TokenRing" },
112 { ARPHRD_ARCNET, "ArcNet" },
113 { ARPHRD_FRELAY, "FrameRelay" },
114 { ARPHRD_STRIP, "Strip" },
115 { ARPHRD_IEEE1394, "IEEE 1394" },
116 { ARPHRD_ATM2225, "ATM" },
117 { ARPHRD_INFINIBAND, "InfiniBand" },
122 * ATM Address Resolution Protocol.
124 * See RFC 2225 for protocol description. ATMARP packets are similar
125 * to ARP packets, except that there are no length fields for the
126 * protocol address - instead, there are type/length fields for
127 * the ATM number and subaddress - and the hardware addresses consist
128 * of an ATM number and an ATM subaddress.
130 struct atmarp_pkthdr {
131 nd_uint16_t aar_hrd; /* format of hardware address */
132 nd_uint16_t aar_pro; /* format of protocol address */
133 nd_uint8_t aar_shtl; /* length of source ATM number */
134 nd_uint8_t aar_sstl; /* length of source ATM subaddress */
135 #define ATMARP_IS_E164 0x40 /* bit in type/length for E.164 format */
136 #define ATMARP_LEN_MASK 0x3F /* length of {sub}address in type/length */
137 nd_uint16_t aar_op; /* same as regular ARP */
138 nd_uint8_t aar_spln; /* length of source protocol address */
139 nd_uint8_t aar_thtl; /* length of target ATM number */
140 nd_uint8_t aar_tstl; /* length of target ATM subaddress */
141 nd_uint8_t aar_tpln; /* length of target protocol address */
143 * The remaining fields are variable in size,
144 * according to the sizes above.
147 nd_byte aar_sha[]; /* source ATM number */
148 nd_byte aar_ssa[]; /* source ATM subaddress */
149 nd_byte aar_spa[]; /* sender protocol address */
150 nd_byte aar_tha[]; /* target ATM number */
151 nd_byte aar_tsa[]; /* target ATM subaddress */
152 nd_byte aar_tpa[]; /* target protocol address */
155 #define ATMHRD(ap) GET_BE_U_2((ap)->aar_hrd)
156 #define ATMSHRD_LEN(ap) (GET_U_1((ap)->aar_shtl) & ATMARP_LEN_MASK)
157 #define ATMSSLN(ap) (GET_U_1((ap)->aar_sstl) & ATMARP_LEN_MASK)
158 #define ATMSPROTO_LEN(ap) GET_U_1((ap)->aar_spln)
159 #define ATMOP(ap) GET_BE_U_2((ap)->aar_op)
160 #define ATMPRO(ap) GET_BE_U_2((ap)->aar_pro)
161 #define ATMTHRD_LEN(ap) (GET_U_1((ap)->aar_thtl) & ATMARP_LEN_MASK)
162 #define ATMTSLN(ap) (GET_U_1((ap)->aar_tstl) & ATMARP_LEN_MASK)
163 #define ATMTPROTO_LEN(ap) GET_U_1((ap)->aar_tpln)
164 #define aar_sha(ap) ((const u_char *)((ap)+1))
165 #define aar_ssa(ap) (aar_sha(ap) + ATMSHRD_LEN(ap))
166 #define aar_spa(ap) (aar_ssa(ap) + ATMSSLN(ap))
167 #define aar_tha(ap) (aar_spa(ap) + ATMSPROTO_LEN(ap))
168 #define aar_tsa(ap) (aar_tha(ap) + ATMTHRD_LEN(ap))
169 #define aar_tpa(ap) (aar_tsa(ap) + ATMTSLN(ap))
172 #define ATMSHA(ap) (aar_sha(ap))
173 #define ATMSSA(ap) (aar_ssa(ap))
174 #define ATMSPA(ap) (aar_spa(ap))
175 #define ATMTHA(ap) (aar_tha(ap))
176 #define ATMTSA(ap) (aar_tsa(ap))
177 #define ATMTPA(ap) (aar_tpa(ap))
180 isnonzero(netdissect_options *ndo, const u_char *a, size_t len)
192 tpaddr_print_ip(netdissect_options *ndo,
193 const struct arp_pkthdr *ap, u_short pro)
195 if (pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL)
196 ND_PRINT("<wrong proto type>");
197 else if (PROTO_LEN(ap) != 4)
198 ND_PRINT("<wrong len>");
200 ND_PRINT("%s", GET_IPADDR_STRING(TPA(ap)));
204 spaddr_print_ip(netdissect_options *ndo,
205 const struct arp_pkthdr *ap, u_short pro)
207 if (pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL)
208 ND_PRINT("<wrong proto type>");
209 else if (PROTO_LEN(ap) != 4)
210 ND_PRINT("<wrong len>");
212 ND_PRINT("%s", GET_IPADDR_STRING(SPA(ap)));
216 atmarp_addr_print(netdissect_options *ndo,
217 const u_char *ha, u_int ha_len, const u_char *srca,
221 ND_PRINT("<No address>");
223 ND_PRINT("%s", GET_LINKADDR_STRING(ha, LINKADDR_ATM, ha_len));
226 GET_LINKADDR_STRING(srca, LINKADDR_ATM, srca_len));
231 atmarp_tpaddr_print(netdissect_options *ndo,
232 const struct atmarp_pkthdr *ap, u_short pro)
234 if (pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL)
235 ND_PRINT("<wrong proto type>");
236 else if (ATMTPROTO_LEN(ap) != 4)
237 ND_PRINT("<wrong tplen>");
239 ND_PRINT("%s", GET_IPADDR_STRING(ATMTPA(ap)));
243 atmarp_spaddr_print(netdissect_options *ndo,
244 const struct atmarp_pkthdr *ap, u_short pro)
246 if (pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL)
247 ND_PRINT("<wrong proto type>");
248 else if (ATMSPROTO_LEN(ap) != 4)
249 ND_PRINT("<wrong splen>");
251 ND_PRINT("%s", GET_IPADDR_STRING(ATMSPA(ap)));
255 atmarp_print(netdissect_options *ndo,
256 const u_char *bp, u_int length, u_int caplen)
258 const struct atmarp_pkthdr *ap;
259 u_short pro, hrd, op;
261 ap = (const struct atmarp_pkthdr *)bp;
268 ND_TCHECK_LEN(ATMTPA(ap), ATMTPROTO_LEN(ap));
270 if (!ndo->ndo_eflag) {
274 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) ||
275 ATMSPROTO_LEN(ap) != 4 ||
276 ATMTPROTO_LEN(ap) != 4 ||
278 ND_PRINT("%s, %s (len %u/%u)",
279 tok2str(arphrd_values, "Unknown Hardware (%u)", hrd),
280 tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro),
284 /* don't know about the address formats */
285 if (!ndo->ndo_vflag) {
290 /* print operation */
292 ndo->ndo_vflag ? ", " : "",
293 tok2str(arpop_values, "Unknown (%u)", op));
298 ND_PRINT("who-has ");
299 atmarp_tpaddr_print(ndo, ap, pro);
300 if (ATMTHRD_LEN(ap) != 0) {
302 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap),
303 ATMTSA(ap), ATMTSLN(ap));
307 atmarp_spaddr_print(ndo, ap, pro);
311 atmarp_spaddr_print(ndo, ap, pro);
313 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap),
317 case ARPOP_INVREQUEST:
319 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), ATMTSA(ap),
322 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap),
327 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap),
330 atmarp_spaddr_print(ndo, ap, pro);
335 atmarp_spaddr_print(ndo, ap, pro);
339 ND_DEFAULTPRINT((const u_char *)ap, caplen);
344 ND_PRINT(", length %u", length);
348 arp_print(netdissect_options *ndo,
349 const u_char *bp, u_int length, u_int caplen)
351 const struct arp_pkthdr *ap;
352 u_short pro, hrd, op, linkaddr;
354 ndo->ndo_protocol = "arp";
355 ap = (const struct arp_pkthdr *)bp;
363 /* if its ATM then call the ATM ARP printer
364 for Frame-relay ARP most of the fields
365 are similar to Ethernet so overload the Ethernet Printer
366 and set the linkaddr type for GET_LINKADDR_STRING() accordingly */
370 atmarp_print(ndo, bp, length, caplen);
373 linkaddr = LINKADDR_FRELAY;
376 linkaddr = LINKADDR_ETHER;
380 ND_TCHECK_LEN(TPA(ap), PROTO_LEN(ap));
382 if (!ndo->ndo_eflag) {
386 /* print hardware type/len and proto type/len */
387 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) ||
388 PROTO_LEN(ap) != 4 ||
391 ND_PRINT("%s (len %u), %s (len %u)",
392 tok2str(arphrd_values, "Unknown Hardware (%u)", hrd),
394 tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro),
397 /* don't know about the address formats */
398 if (!ndo->ndo_vflag) {
403 /* print operation */
405 ndo->ndo_vflag ? ", " : "",
406 tok2str(arpop_values, "Unknown (%u)", op));
411 ND_PRINT("who-has ");
412 tpaddr_print_ip(ndo, ap, pro);
413 if (isnonzero(ndo, (const u_char *)THA(ap), HRD_LEN(ap)))
415 GET_LINKADDR_STRING(THA(ap), linkaddr, HRD_LEN(ap)));
417 spaddr_print_ip(ndo, ap, pro);
421 spaddr_print_ip(ndo, ap, pro);
422 ND_PRINT(" is-at %s",
423 GET_LINKADDR_STRING(SHA(ap), linkaddr, HRD_LEN(ap)));
426 case ARPOP_REVREQUEST:
428 * XXX - GET_LINKADDR_STRING() may return a pointer to
429 * a static buffer, so we only have one call to it per
432 * This should be done in a cleaner fashion.
434 ND_PRINT("who-is %s",
435 GET_LINKADDR_STRING(THA(ap), linkaddr, HRD_LEN(ap)));
437 GET_LINKADDR_STRING(SHA(ap), linkaddr, HRD_LEN(ap)));
442 GET_LINKADDR_STRING(THA(ap), linkaddr, HRD_LEN(ap)));
443 tpaddr_print_ip(ndo, ap, pro);
446 case ARPOP_INVREQUEST:
448 * XXX - GET_LINKADDR_STRING() may return a pointer to
449 * a static buffer, so we only have one call to it per
452 * This should be done in a cleaner fashion.
454 ND_PRINT("who-is %s",
455 GET_LINKADDR_STRING(THA(ap), linkaddr, HRD_LEN(ap)));
457 GET_LINKADDR_STRING(SHA(ap), linkaddr, HRD_LEN(ap)));
462 GET_LINKADDR_STRING(SHA(ap), linkaddr, HRD_LEN(ap)));
463 spaddr_print_ip(ndo, ap, pro);
467 ND_DEFAULTPRINT((const u_char *)ap, caplen);
472 ND_PRINT(", length %u", length);