1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 3 * The Regents of the University of California. All rights reserved. 4 * 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 16 * written permission. 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. 20 */ 21 22 #define NETDISSECT_REWORKED 23 #ifdef HAVE_CONFIG_H 24 #include "config.h" 25 #endif 26 27 #include <tcpdump-stdinc.h> 28 29 #include <string.h> 30 31 #include "interface.h" 32 #include "addrtoname.h" 33 #include "ether.h" 34 #include "ethertype.h" 35 #include "extract.h" /* must come after interface.h */ 36 37 static const char tstr[] = "[|ARP]"; 38 39 /* 40 * Address Resolution Protocol. 41 * 42 * See RFC 826 for protocol description. ARP packets are variable 43 * in size; the arphdr structure defines the fixed-length portion. 44 * Protocol type values are the same as those for 10 Mb/s Ethernet. 45 * It is followed by the variable-sized fields ar_sha, arp_spa, 46 * arp_tha and arp_tpa in that order, according to the lengths 47 * specified. Field names used correspond to RFC 826. 48 */ 49 struct arp_pkthdr { 50 u_short ar_hrd; /* format of hardware address */ 51 #define ARPHRD_ETHER 1 /* ethernet hardware format */ 52 #define ARPHRD_IEEE802 6 /* token-ring hardware format */ 53 #define ARPHRD_ARCNET 7 /* arcnet hardware format */ 54 #define ARPHRD_FRELAY 15 /* frame relay hardware format */ 55 #define ARPHRD_ATM2225 19 /* ATM (RFC 2225) */ 56 #define ARPHRD_STRIP 23 /* Ricochet Starmode Radio hardware format */ 57 #define ARPHRD_IEEE1394 24 /* IEEE 1394 (FireWire) hardware format */ 58 u_short ar_pro; /* format of protocol address */ 59 u_char ar_hln; /* length of hardware address */ 60 u_char ar_pln; /* length of protocol address */ 61 u_short ar_op; /* one of: */ 62 #define ARPOP_REQUEST 1 /* request to resolve address */ 63 #define ARPOP_REPLY 2 /* response to previous request */ 64 #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */ 65 #define ARPOP_REVREPLY 4 /* response giving protocol address */ 66 #define ARPOP_INVREQUEST 8 /* request to identify peer */ 67 #define ARPOP_INVREPLY 9 /* response identifying peer */ 68 #define ARPOP_NAK 10 /* NAK - only valif for ATM ARP */ 69 70 /* 71 * The remaining fields are variable in size, 72 * according to the sizes above. 73 */ 74 #ifdef COMMENT_ONLY 75 u_char ar_sha[]; /* sender hardware address */ 76 u_char ar_spa[]; /* sender protocol address */ 77 u_char ar_tha[]; /* target hardware address */ 78 u_char ar_tpa[]; /* target protocol address */ 79 #endif 80 #define ar_sha(ap) (((const u_char *)((ap)+1))+0) 81 #define ar_spa(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln) 82 #define ar_tha(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln+(ap)->ar_pln) 83 #define ar_tpa(ap) (((const u_char *)((ap)+1))+2*(ap)->ar_hln+(ap)->ar_pln) 84 }; 85 86 #define ARP_HDRLEN 8 87 88 #define HRD(ap) EXTRACT_16BITS(&(ap)->ar_hrd) 89 #define HRD_LEN(ap) ((ap)->ar_hln) 90 #define PROTO_LEN(ap) ((ap)->ar_pln) 91 #define OP(ap) EXTRACT_16BITS(&(ap)->ar_op) 92 #define PRO(ap) EXTRACT_16BITS(&(ap)->ar_pro) 93 #define SHA(ap) (ar_sha(ap)) 94 #define SPA(ap) (ar_spa(ap)) 95 #define THA(ap) (ar_tha(ap)) 96 #define TPA(ap) (ar_tpa(ap)) 97 98 99 static const struct tok arpop_values[] = { 100 { ARPOP_REQUEST, "Request" }, 101 { ARPOP_REPLY, "Reply" }, 102 { ARPOP_REVREQUEST, "Reverse Request" }, 103 { ARPOP_REVREPLY, "Reverse Reply" }, 104 { ARPOP_INVREQUEST, "Inverse Request" }, 105 { ARPOP_INVREPLY, "Inverse Reply" }, 106 { ARPOP_NAK, "NACK Reply" }, 107 { 0, NULL } 108 }; 109 110 static const struct tok arphrd_values[] = { 111 { ARPHRD_ETHER, "Ethernet" }, 112 { ARPHRD_IEEE802, "TokenRing" }, 113 { ARPHRD_ARCNET, "ArcNet" }, 114 { ARPHRD_FRELAY, "FrameRelay" }, 115 { ARPHRD_STRIP, "Strip" }, 116 { ARPHRD_IEEE1394, "IEEE 1394" }, 117 { ARPHRD_ATM2225, "ATM" }, 118 { 0, NULL } 119 }; 120 121 /* 122 * ATM Address Resolution Protocol. 123 * 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. 129 */ 130 struct atmarp_pkthdr { 131 u_short aar_hrd; /* format of hardware address */ 132 u_short aar_pro; /* format of protocol address */ 133 u_char aar_shtl; /* length of source ATM number */ 134 u_char 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 u_short aar_op; /* same as regular ARP */ 138 u_char aar_spln; /* length of source protocol address */ 139 u_char aar_thtl; /* length of target ATM number */ 140 u_char aar_tstl; /* length of target ATM subaddress */ 141 u_char aar_tpln; /* length of target protocol address */ 142 /* 143 * The remaining fields are variable in size, 144 * according to the sizes above. 145 */ 146 #ifdef COMMENT_ONLY 147 u_char aar_sha[]; /* source ATM number */ 148 u_char aar_ssa[]; /* source ATM subaddress */ 149 u_char aar_spa[]; /* sender protocol address */ 150 u_char aar_tha[]; /* target ATM number */ 151 u_char aar_tsa[]; /* target ATM subaddress */ 152 u_char aar_tpa[]; /* target protocol address */ 153 #endif 154 155 #define ATMHRD(ap) EXTRACT_16BITS(&(ap)->aar_hrd) 156 #define ATMSHRD_LEN(ap) ((ap)->aar_shtl & ATMARP_LEN_MASK) 157 #define ATMSSLN(ap) ((ap)->aar_sstl & ATMARP_LEN_MASK) 158 #define ATMSPROTO_LEN(ap) ((ap)->aar_spln) 159 #define ATMOP(ap) EXTRACT_16BITS(&(ap)->aar_op) 160 #define ATMPRO(ap) EXTRACT_16BITS(&(ap)->aar_pro) 161 #define ATMTHRD_LEN(ap) ((ap)->aar_thtl & ATMARP_LEN_MASK) 162 #define ATMTSLN(ap) ((ap)->aar_tstl & ATMARP_LEN_MASK) 163 #define ATMTPROTO_LEN(ap) ((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)) 170 }; 171 172 #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)) 178 179 static u_char ezero[6]; 180 181 static void 182 atmarp_addr_print(netdissect_options *ndo, 183 const u_char *ha, u_int ha_len, const u_char *srca, 184 u_int srca_len) 185 { 186 if (ha_len == 0) 187 ND_PRINT((ndo, "<No address>")); 188 else { 189 ND_PRINT((ndo, "%s", linkaddr_string(ndo, ha, LINKADDR_ATM, ha_len))); 190 if (srca_len != 0) 191 ND_PRINT((ndo, ",%s", 192 linkaddr_string(ndo, srca, LINKADDR_ATM, srca_len))); 193 } 194 } 195 196 static void 197 atmarp_print(netdissect_options *ndo, 198 const u_char *bp, u_int length, u_int caplen) 199 { 200 const struct atmarp_pkthdr *ap; 201 u_short pro, hrd, op; 202 203 ap = (const struct atmarp_pkthdr *)bp; 204 ND_TCHECK(*ap); 205 206 hrd = ATMHRD(ap); 207 pro = ATMPRO(ap); 208 op = ATMOP(ap); 209 210 if (!ND_TTEST2(*aar_tpa(ap), ATMTPROTO_LEN(ap))) { 211 ND_PRINT((ndo, "%s", tstr)); 212 ND_DEFAULTPRINT((const u_char *)ap, length); 213 return; 214 } 215 216 if (!ndo->ndo_eflag) { 217 ND_PRINT((ndo, "ARP, ")); 218 } 219 220 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || 221 ATMSPROTO_LEN(ap) != 4 || 222 ATMTPROTO_LEN(ap) != 4 || 223 ndo->ndo_vflag) { 224 ND_PRINT((ndo, "%s, %s (len %u/%u)", 225 tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), 226 tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), 227 ATMSPROTO_LEN(ap), 228 ATMTPROTO_LEN(ap))); 229 230 /* don't know know about the address formats */ 231 if (!ndo->ndo_vflag) { 232 goto out; 233 } 234 } 235 236 /* print operation */ 237 ND_PRINT((ndo, "%s%s ", 238 ndo->ndo_vflag ? ", " : "", 239 tok2str(arpop_values, "Unknown (%u)", op))); 240 241 switch (op) { 242 243 case ARPOP_REQUEST: 244 ND_PRINT((ndo, "who-has %s", ipaddr_string(ndo, ATMTPA(ap)))); 245 if (ATMTHRD_LEN(ap) != 0) { 246 ND_PRINT((ndo, " (")); 247 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), 248 ATMTSA(ap), ATMTSLN(ap)); 249 ND_PRINT((ndo, ")")); 250 } 251 ND_PRINT((ndo, "tell %s", ipaddr_string(ndo, ATMSPA(ap)))); 252 break; 253 254 case ARPOP_REPLY: 255 ND_PRINT((ndo, "%s is-at ", ipaddr_string(ndo, ATMSPA(ap)))); 256 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 257 ATMSSLN(ap)); 258 break; 259 260 case ARPOP_INVREQUEST: 261 ND_PRINT((ndo, "who-is ")); 262 atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), ATMTSA(ap), 263 ATMTSLN(ap)); 264 ND_PRINT((ndo, " tell ")); 265 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 266 ATMSSLN(ap)); 267 break; 268 269 case ARPOP_INVREPLY: 270 atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 271 ATMSSLN(ap)); 272 ND_PRINT((ndo, "at %s", ipaddr_string(ndo, ATMSPA(ap)))); 273 break; 274 275 case ARPOP_NAK: 276 ND_PRINT((ndo, "for %s", ipaddr_string(ndo, ATMSPA(ap)))); 277 break; 278 279 default: 280 ND_DEFAULTPRINT((const u_char *)ap, caplen); 281 return; 282 } 283 284 out: 285 ND_PRINT((ndo, ", length %u", length)); 286 return; 287 288 trunc: 289 ND_PRINT((ndo, "%s", tstr)); 290 } 291 292 void 293 arp_print(netdissect_options *ndo, 294 const u_char *bp, u_int length, u_int caplen) 295 { 296 const struct arp_pkthdr *ap; 297 u_short pro, hrd, op, linkaddr; 298 299 ap = (const struct arp_pkthdr *)bp; 300 ND_TCHECK(*ap); 301 302 hrd = HRD(ap); 303 pro = PRO(ap); 304 op = OP(ap); 305 306 307 /* if its ATM then call the ATM ARP printer 308 for Frame-relay ARP most of the fields 309 are similar to Ethernet so overload the Ethernet Printer 310 and set the linkaddr type for linkaddr_string(ndo, ) accordingly */ 311 312 switch(hrd) { 313 case ARPHRD_ATM2225: 314 atmarp_print(ndo, bp, length, caplen); 315 return; 316 case ARPHRD_FRELAY: 317 linkaddr = LINKADDR_FRELAY; 318 break; 319 default: 320 linkaddr = LINKADDR_ETHER; 321 break; 322 } 323 324 if (!ND_TTEST2(*ar_tpa(ap), PROTO_LEN(ap))) { 325 ND_PRINT((ndo, "%s", tstr)); 326 ND_DEFAULTPRINT((const u_char *)ap, length); 327 return; 328 } 329 330 if (!ndo->ndo_eflag) { 331 ND_PRINT((ndo, "ARP, ")); 332 } 333 334 /* print hardware type/len and proto type/len */ 335 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || 336 PROTO_LEN(ap) != 4 || 337 HRD_LEN(ap) == 0 || 338 ndo->ndo_vflag) { 339 ND_PRINT((ndo, "%s (len %u), %s (len %u)", 340 tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), 341 HRD_LEN(ap), 342 tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), 343 PROTO_LEN(ap))); 344 345 /* don't know know about the address formats */ 346 if (!ndo->ndo_vflag) { 347 goto out; 348 } 349 } 350 351 /* print operation */ 352 ND_PRINT((ndo, "%s%s ", 353 ndo->ndo_vflag ? ", " : "", 354 tok2str(arpop_values, "Unknown (%u)", op))); 355 356 switch (op) { 357 358 case ARPOP_REQUEST: 359 ND_PRINT((ndo, "who-has %s", ipaddr_string(ndo, TPA(ap)))); 360 if (memcmp((const char *)ezero, (const char *)THA(ap), HRD_LEN(ap)) != 0) 361 ND_PRINT((ndo, " (%s)", 362 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)))); 363 ND_PRINT((ndo, " tell %s", ipaddr_string(ndo, SPA(ap)))); 364 break; 365 366 case ARPOP_REPLY: 367 ND_PRINT((ndo, "%s is-at %s", 368 ipaddr_string(ndo, SPA(ap)), 369 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)))); 370 break; 371 372 case ARPOP_REVREQUEST: 373 ND_PRINT((ndo, "who-is %s tell %s", 374 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)), 375 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)))); 376 break; 377 378 case ARPOP_REVREPLY: 379 ND_PRINT((ndo, "%s at %s", 380 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)), 381 ipaddr_string(ndo, TPA(ap)))); 382 break; 383 384 case ARPOP_INVREQUEST: 385 ND_PRINT((ndo, "who-is %s tell %s", 386 linkaddr_string(ndo, THA(ap), linkaddr, HRD_LEN(ap)), 387 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)))); 388 break; 389 390 case ARPOP_INVREPLY: 391 ND_PRINT((ndo,"%s at %s", 392 linkaddr_string(ndo, SHA(ap), linkaddr, HRD_LEN(ap)), 393 ipaddr_string(ndo, SPA(ap)))); 394 break; 395 396 default: 397 ND_DEFAULTPRINT((const u_char *)ap, caplen); 398 return; 399 } 400 401 out: 402 ND_PRINT((ndo, ", length %u", length)); 403 404 return; 405 trunc: 406 ND_PRINT((ndo, "%s", tstr)); 407 } 408 409 /* 410 * Local Variables: 411 * c-style: bsd 412 * End: 413 */ 414 415
