print-arp.c revision 190207
117680Spst/* 217680Spst * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 317680Spst * The Regents of the University of California. All rights reserved. 417680Spst * 517680Spst * Redistribution and use in source and binary forms, with or without 617680Spst * modification, are permitted provided that: (1) source code distributions 717680Spst * retain the above copyright notice and this paragraph in its entirety, (2) 817680Spst * distributions including binary code include the above copyright notice and 917680Spst * this paragraph in its entirety in the documentation or other materials 1017680Spst * provided with the distribution, and (3) all advertising materials mentioning 1117680Spst * features or use of this software display the following acknowledgement: 1217680Spst * ``This product includes software developed by the University of California, 1317680Spst * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 1417680Spst * the University nor the names of its contributors may be used to endorse 1517680Spst * or promote products derived from this software without specific prior 1617680Spst * written permission. 1717680Spst * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 1817680Spst * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 1917680Spst * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 2017680Spst * 2117680Spst * $FreeBSD: head/contrib/tcpdump/print-arp.c 190207 2009-03-21 18:30:25Z rpaulo $ 2217680Spst */ 2317680Spst 2417680Spst#ifndef lint 2526180Sfennerstatic const char rcsid[] _U_ = 2626180Sfenner "@(#) $Header: /tcpdump/master/tcpdump/print-arp.c,v 1.66 2006-03-03 22:53:21 hannes Exp $ (LBL)"; 2717680Spst#endif 2817680Spst 2917680Spst#ifdef HAVE_CONFIG_H 3017680Spst#include "config.h" 3117680Spst#endif 3217680Spst 3317680Spst#include <tcpdump-stdinc.h> 3417680Spst 3517680Spst#include <stdio.h> 3617680Spst#include <string.h> 3717680Spst 3817680Spst#include "netdissect.h" 3917680Spst#include "addrtoname.h" 4017680Spst#include "ether.h" 4117680Spst#include "ethertype.h" 4217680Spst#include "extract.h" /* must come after interface.h */ 4317680Spst 4417680Spst/* 4517680Spst * Address Resolution Protocol. 4617680Spst * 4717680Spst * See RFC 826 for protocol description. ARP packets are variable 4817680Spst * in size; the arphdr structure defines the fixed-length portion. 4917680Spst * Protocol type values are the same as those for 10 Mb/s Ethernet. 5017680Spst * It is followed by the variable-sized fields ar_sha, arp_spa, 5117680Spst * arp_tha and arp_tpa in that order, according to the lengths 5217680Spst * specified. Field names used correspond to RFC 826. 5317680Spst */ 5417680Spststruct arp_pkthdr { 5517680Spst u_short ar_hrd; /* format of hardware address */ 5617680Spst#define ARPHRD_ETHER 1 /* ethernet hardware format */ 5717680Spst#define ARPHRD_IEEE802 6 /* token-ring hardware format */ 5817680Spst#define ARPHRD_ARCNET 7 /* arcnet hardware format */ 5917680Spst#define ARPHRD_FRELAY 15 /* frame relay hardware format */ 6017680Spst#define ARPHRD_ATM2225 19 /* ATM (RFC 2225) */ 6117680Spst#define ARPHRD_STRIP 23 /* Ricochet Starmode Radio hardware format */ 6217680Spst#define ARPHRD_IEEE1394 24 /* IEEE 1394 (FireWire) hardware format */ 6317680Spst u_short ar_pro; /* format of protocol address */ 6417680Spst u_char ar_hln; /* length of hardware address */ 6517680Spst u_char ar_pln; /* length of protocol address */ 6617680Spst u_short ar_op; /* one of: */ 6717680Spst#define ARPOP_REQUEST 1 /* request to resolve address */ 6817680Spst#define ARPOP_REPLY 2 /* response to previous request */ 6917680Spst#define ARPOP_REVREQUEST 3 /* request protocol address given hardware */ 7017680Spst#define ARPOP_REVREPLY 4 /* response giving protocol address */ 7117680Spst#define ARPOP_INVREQUEST 8 /* request to identify peer */ 7217680Spst#define ARPOP_INVREPLY 9 /* response identifying peer */ 7317680Spst#define ARPOP_NAK 10 /* NAK - only valif for ATM ARP */ 7417680Spst 7517680Spst/* 7617680Spst * The remaining fields are variable in size, 7717680Spst * according to the sizes above. 7817680Spst */ 7917680Spst#ifdef COMMENT_ONLY 8017680Spst u_char ar_sha[]; /* sender hardware address */ 8117680Spst u_char ar_spa[]; /* sender protocol address */ 8217680Spst u_char ar_tha[]; /* target hardware address */ 8317680Spst u_char ar_tpa[]; /* target protocol address */ 8417680Spst#endif 8517680Spst#define ar_sha(ap) (((const u_char *)((ap)+1))+0) 8617680Spst#define ar_spa(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln) 8717680Spst#define ar_tha(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln+(ap)->ar_pln) 8817680Spst#define ar_tpa(ap) (((const u_char *)((ap)+1))+2*(ap)->ar_hln+(ap)->ar_pln) 8917680Spst}; 9017680Spst 9117680Spst#define ARP_HDRLEN 8 9217680Spst 9317680Spst#define HRD(ap) EXTRACT_16BITS(&(ap)->ar_hrd) 9417680Spst#define HRD_LEN(ap) ((ap)->ar_hln) 9517680Spst#define PROTO_LEN(ap) ((ap)->ar_pln) 9617680Spst#define OP(ap) EXTRACT_16BITS(&(ap)->ar_op) 9717680Spst#define PRO(ap) EXTRACT_16BITS(&(ap)->ar_pro) 9817680Spst#define SHA(ap) (ar_sha(ap)) 9917680Spst#define SPA(ap) (ar_spa(ap)) 10017680Spst#define THA(ap) (ar_tha(ap)) 10117680Spst#define TPA(ap) (ar_tpa(ap)) 10217680Spst 10317680Spst 10417680Spststruct tok arpop_values[] = { 10517680Spst { ARPOP_REQUEST, "Request" }, 10617680Spst { ARPOP_REPLY, "Reply" }, 10717680Spst { ARPOP_REVREQUEST, "Reverse Request" }, 10817680Spst { ARPOP_REVREPLY, "Reverse Reply" }, 10917680Spst { ARPOP_INVREQUEST, "Inverse Request" }, 11017680Spst { ARPOP_INVREPLY, "Inverse Reply" }, 11117680Spst { ARPOP_NAK, "NACK Reply" }, 11217680Spst { 0, NULL } 11326180Sfenner}; 11426180Sfenner 11526180Sfennerstruct tok arphrd_values[] = { 11626180Sfenner { ARPHRD_ETHER, "Ethernet" }, 11726180Sfenner { ARPHRD_IEEE802, "TokenRing" }, 11826180Sfenner { ARPHRD_ARCNET, "ArcNet" }, 11917680Spst { ARPHRD_FRELAY, "FrameRelay" }, 12026180Sfenner { ARPHRD_STRIP, "Strip" }, 12126180Sfenner { ARPHRD_IEEE1394, "IEEE 1394" }, 12226180Sfenner { ARPHRD_ATM2225, "ATM" }, 12326180Sfenner { 0, NULL } 12426180Sfenner}; 12526180Sfenner 12617680Spst/* 12717680Spst * ATM Address Resolution Protocol. 12817680Spst * 12917680Spst * See RFC 2225 for protocol description. ATMARP packets are similar 13017680Spst * to ARP packets, except that there are no length fields for the 13117680Spst * protocol address - instead, there are type/length fields for 13217680Spst * the ATM number and subaddress - and the hardware addresses consist 13317680Spst * of an ATM number and an ATM subaddress. 13417680Spst */ 13517680Spststruct atmarp_pkthdr { 13617680Spst u_short aar_hrd; /* format of hardware address */ 13717680Spst u_short aar_pro; /* format of protocol address */ 13817680Spst u_char aar_shtl; /* length of source ATM number */ 13917680Spst u_char aar_sstl; /* length of source ATM subaddress */ 14017680Spst#define ATMARP_IS_E164 0x40 /* bit in type/length for E.164 format */ 14117680Spst#define ATMARP_LEN_MASK 0x3F /* length of {sub}address in type/length */ 14217680Spst u_short aar_op; /* same as regular ARP */ 14317680Spst u_char aar_spln; /* length of source protocol address */ 14417680Spst u_char aar_thtl; /* length of target ATM number */ 14517680Spst u_char aar_tstl; /* length of target ATM subaddress */ 14617680Spst u_char aar_tpln; /* length of target protocol address */ 14717680Spst/* 14817680Spst * The remaining fields are variable in size, 14917680Spst * according to the sizes above. 15017680Spst */ 15117680Spst#ifdef COMMENT_ONLY 15217680Spst u_char aar_sha[]; /* source ATM number */ 15317680Spst u_char aar_ssa[]; /* source ATM subaddress */ 15417680Spst u_char aar_spa[]; /* sender protocol address */ 15517680Spst u_char aar_tha[]; /* target ATM number */ 15617680Spst u_char aar_tsa[]; /* target ATM subaddress */ 15717680Spst u_char aar_tpa[]; /* target protocol address */ 15817680Spst#endif 15917680Spst 16017680Spst#define ATMHRD(ap) EXTRACT_16BITS(&(ap)->aar_hrd) 16117680Spst#define ATMSHRD_LEN(ap) ((ap)->aar_shtl & ATMARP_LEN_MASK) 16217680Spst#define ATMSSLN(ap) ((ap)->aar_sstl & ATMARP_LEN_MASK) 16317680Spst#define ATMSPROTO_LEN(ap) ((ap)->aar_spln) 16417680Spst#define ATMOP(ap) EXTRACT_16BITS(&(ap)->aar_op) 16517680Spst#define ATMPRO(ap) EXTRACT_16BITS(&(ap)->aar_pro) 16617680Spst#define ATMTHRD_LEN(ap) ((ap)->aar_thtl & ATMARP_LEN_MASK) 16717680Spst#define ATMTSLN(ap) ((ap)->aar_tstl & ATMARP_LEN_MASK) 16817680Spst#define ATMTPROTO_LEN(ap) ((ap)->aar_tpln) 16917680Spst#define aar_sha(ap) ((const u_char *)((ap)+1)) 17017680Spst#define aar_ssa(ap) (aar_sha(ap) + ATMSHRD_LEN(ap)) 17117680Spst#define aar_spa(ap) (aar_ssa(ap) + ATMSSLN(ap)) 17217680Spst#define aar_tha(ap) (aar_spa(ap) + ATMSPROTO_LEN(ap)) 17317680Spst#define aar_tsa(ap) (aar_tha(ap) + ATMTHRD_LEN(ap)) 17417680Spst#define aar_tpa(ap) (aar_tsa(ap) + ATMTSLN(ap)) 17517680Spst}; 17617680Spst 17717680Spst#define ATMSHA(ap) (aar_sha(ap)) 17817680Spst#define ATMSSA(ap) (aar_ssa(ap)) 17917680Spst#define ATMSPA(ap) (aar_spa(ap)) 18017680Spst#define ATMTHA(ap) (aar_tha(ap)) 18117680Spst#define ATMTSA(ap) (aar_tsa(ap)) 18217680Spst#define ATMTPA(ap) (aar_tpa(ap)) 18317680Spst 18417680Spststatic u_char ezero[6]; 18517680Spst 18617680Spststatic void 18717680Spstatmarp_addr_print(netdissect_options *ndo, 18817680Spst const u_char *ha, u_int ha_len, const u_char *srca, 18917680Spst u_int srca_len) 19017680Spst{ 19117680Spst if (ha_len == 0) 19217680Spst ND_PRINT((ndo, "<No address>")); 19317680Spst else { 19417680Spst ND_PRINT((ndo, "%s", linkaddr_string(ha, LINKADDR_ATM, ha_len))); 19517680Spst if (srca_len != 0) 19617680Spst ND_PRINT((ndo, ",%s", 19717680Spst linkaddr_string(srca, LINKADDR_ATM, srca_len))); 19817680Spst } 19917680Spst} 20017680Spst 20117680Spststatic void 20217680Spstatmarp_print(netdissect_options *ndo, 20317680Spst const u_char *bp, u_int length, u_int caplen) 20417680Spst{ 20517680Spst const struct atmarp_pkthdr *ap; 20617680Spst u_short pro, hrd, op; 20717680Spst 20817680Spst ap = (const struct atmarp_pkthdr *)bp; 20917680Spst ND_TCHECK(*ap); 21017680Spst 21117680Spst hrd = ATMHRD(ap); 21217680Spst pro = ATMPRO(ap); 21317680Spst op = ATMOP(ap); 21417680Spst 21517680Spst if (!ND_TTEST2(*aar_tpa(ap), ATMTPROTO_LEN(ap))) { 21617680Spst ND_PRINT((ndo, "[|ARP]")); 21717680Spst ND_DEFAULTPRINT((const u_char *)ap, length); 21817680Spst return; 21917680Spst } 22017680Spst 22117680Spst if (!ndo->ndo_eflag) { 22217680Spst ND_PRINT((ndo, "ARP, ")); 22317680Spst } 22417680Spst 22517680Spst if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || 22617680Spst ATMSPROTO_LEN(ap) != 4 || 22717680Spst ATMTPROTO_LEN(ap) != 4 || 22817680Spst ndo->ndo_vflag) { 22917680Spst ND_PRINT((ndo, "%s, %s (len %u/%u)", 23017680Spst tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), 23117680Spst tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), 23217680Spst ATMSPROTO_LEN(ap), 23317680Spst ATMTPROTO_LEN(ap))); 23417680Spst 23517680Spst /* don't know know about the address formats */ 23617680Spst if (!ndo->ndo_vflag) { 23717680Spst goto out; 23817680Spst } 23917680Spst } 24017680Spst 24117680Spst /* print operation */ 24217680Spst printf("%s%s ", 24317680Spst ndo->ndo_vflag ? ", " : "", 24417680Spst tok2str(arpop_values, "Unknown (%u)", op)); 24517680Spst 24617680Spst switch (op) { 24717680Spst 24817680Spst case ARPOP_REQUEST: 24917680Spst ND_PRINT((ndo, "who-has %s", ipaddr_string(ATMTPA(ap)))); 25017680Spst if (ATMTHRD_LEN(ap) != 0) { 25117680Spst ND_PRINT((ndo, " (")); 25217680Spst atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), 25317680Spst ATMTSA(ap), ATMTSLN(ap)); 25417680Spst ND_PRINT((ndo, ")")); 25517680Spst } 25617680Spst ND_PRINT((ndo, "tell %s", ipaddr_string(ATMSPA(ap)))); 25717680Spst break; 25817680Spst 25917680Spst case ARPOP_REPLY: 26017680Spst ND_PRINT((ndo, "%s is-at ", ipaddr_string(ATMSPA(ap)))); 26117680Spst atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 26217680Spst ATMSSLN(ap)); 26317680Spst break; 26417680Spst 26517680Spst case ARPOP_INVREQUEST: 26617680Spst ND_PRINT((ndo, "who-is ")); 26717680Spst atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), ATMTSA(ap), 26817680Spst ATMTSLN(ap)); 26917680Spst ND_PRINT((ndo, " tell ")); 27017680Spst atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 27117680Spst ATMSSLN(ap)); 27217680Spst break; 27317680Spst 27417680Spst case ARPOP_INVREPLY: 27517680Spst atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), 27617680Spst ATMSSLN(ap)); 27717680Spst ND_PRINT((ndo, "at %s", ipaddr_string(ATMSPA(ap)))); 27817680Spst break; 27917680Spst 28017680Spst case ARPOP_NAK: 28117680Spst ND_PRINT((ndo, "for %s", ipaddr_string(ATMSPA(ap)))); 28217680Spst break; 28317680Spst 28426180Sfenner default: 28517680Spst ND_DEFAULTPRINT((const u_char *)ap, caplen); 28617680Spst return; 28717680Spst } 28817680Spst 28917680Spst out: 29017680Spst ND_PRINT((ndo, ", length %u", length)); 29117680Spst return; 29217680Spst 29317680Spsttrunc: 29417680Spst ND_PRINT((ndo, "[|ARP]")); 295} 296 297void 298arp_print(netdissect_options *ndo, 299 const u_char *bp, u_int length, u_int caplen) 300{ 301 const struct arp_pkthdr *ap; 302 u_short pro, hrd, op, linkaddr; 303 304 ap = (const struct arp_pkthdr *)bp; 305 ND_TCHECK(*ap); 306 307 hrd = HRD(ap); 308 pro = PRO(ap); 309 op = OP(ap); 310 311 312 /* if its ATM then call the ATM ARP printer 313 for Frame-relay ARP most of the fields 314 are similar to Ethernet so overload the Ethernet Printer 315 and set the linkaddr type for linkaddr_string() accordingly */ 316 317 switch(hrd) { 318 case ARPHRD_ATM2225: 319 atmarp_print(ndo, bp, length, caplen); 320 return; 321 case ARPHRD_FRELAY: 322 linkaddr = LINKADDR_FRELAY; 323 default: 324 linkaddr = LINKADDR_ETHER; 325 break; 326 } 327 328 if (!ND_TTEST2(*ar_tpa(ap), PROTO_LEN(ap))) { 329 ND_PRINT((ndo, "[|ARP]")); 330 ND_DEFAULTPRINT((const u_char *)ap, length); 331 return; 332 } 333 334 if (!ndo->ndo_eflag) { 335 ND_PRINT((ndo, "ARP, ")); 336 } 337 338 /* print hardware type/len and proto type/len */ 339 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || 340 PROTO_LEN(ap) != 4 || 341 HRD_LEN(ap) == 0 || 342 ndo->ndo_vflag) { 343 ND_PRINT((ndo, "%s (len %u), %s (len %u)", 344 tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), 345 HRD_LEN(ap), 346 tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), 347 PROTO_LEN(ap))); 348 349 /* don't know know about the address formats */ 350 if (!ndo->ndo_vflag) { 351 goto out; 352 } 353 } 354 355 /* print operation */ 356 printf("%s%s ", 357 ndo->ndo_vflag ? ", " : "", 358 tok2str(arpop_values, "Unknown (%u)", op)); 359 360 switch (op) { 361 362 case ARPOP_REQUEST: 363 ND_PRINT((ndo, "who-has %s", ipaddr_string(TPA(ap)))); 364 if (memcmp((const char *)ezero, (const char *)THA(ap), HRD_LEN(ap)) != 0) 365 ND_PRINT((ndo, " (%s)", 366 linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)))); 367 ND_PRINT((ndo, " tell %s", ipaddr_string(SPA(ap)))); 368 break; 369 370 case ARPOP_REPLY: 371 ND_PRINT((ndo, "%s is-at %s", 372 ipaddr_string(SPA(ap)), 373 linkaddr_string(SHA(ap), linkaddr, HRD_LEN(ap)))); 374 break; 375 376 case ARPOP_REVREQUEST: 377 ND_PRINT((ndo, "who-is %s tell %s", 378 linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), 379 linkaddr_string(SHA(ap), linkaddr, HRD_LEN(ap)))); 380 break; 381 382 case ARPOP_REVREPLY: 383 ND_PRINT((ndo, "%s at %s", 384 linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), 385 ipaddr_string(TPA(ap)))); 386 break; 387 388 case ARPOP_INVREQUEST: 389 ND_PRINT((ndo, "who-is %s tell %s", 390 linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), 391 linkaddr_string(SHA(ap), linkaddr, HRD_LEN(ap)))); 392 break; 393 394 case ARPOP_INVREPLY: 395 ND_PRINT((ndo,"%s at %s", 396 linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), 397 ipaddr_string(TPA(ap)))); 398 break; 399 400 default: 401 ND_DEFAULTPRINT((const u_char *)ap, caplen); 402 return; 403 } 404 405 out: 406 ND_PRINT((ndo, ", length %u", length)); 407 408 return; 409trunc: 410 ND_PRINT((ndo, "[|ARP]")); 411} 412 413/* 414 * Local Variables: 415 * c-style: bsd 416 * End: 417 */ 418 419