/* * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that: (1) source code distributions * retain the above copyright notice and this paragraph in its entirety, (2) * distributions including binary code include the above copyright notice and * this paragraph in its entirety in the documentation or other materials * provided with the distribution, and (3) all advertising materials mentioning * features or use of this software display the following acknowledgement: * ``This product includes software developed by the University of California, * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of * the University nor the names of its contributors may be used to endorse * or promote products derived from this software without specific prior * written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ #ifndef lint static const char rcsid[] _U_ = "@(#) $Header: /tcpdump/master/tcpdump/print-arp.c,v 1.66 2006-03-03 22:53:21 hannes Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include "netdissect.h" #include "addrtoname.h" #include "ether.h" #include "ethertype.h" #include "extract.h" /* must come after interface.h */ /* * Address Resolution Protocol. * * See RFC 826 for protocol description. ARP packets are variable * in size; the arphdr structure defines the fixed-length portion. * Protocol type values are the same as those for 10 Mb/s Ethernet. * It is followed by the variable-sized fields ar_sha, arp_spa, * arp_tha and arp_tpa in that order, according to the lengths * specified. Field names used correspond to RFC 826. */ struct arp_pkthdr { u_short ar_hrd; /* format of hardware address */ #define ARPHRD_ETHER 1 /* ethernet hardware format */ #define ARPHRD_IEEE802 6 /* token-ring hardware format */ #define ARPHRD_ARCNET 7 /* arcnet hardware format */ #define ARPHRD_FRELAY 15 /* frame relay hardware format */ #define ARPHRD_ATM2225 19 /* ATM (RFC 2225) */ #define ARPHRD_STRIP 23 /* Ricochet Starmode Radio hardware format */ #define ARPHRD_IEEE1394 24 /* IEEE 1394 (FireWire) hardware format */ u_short ar_pro; /* format of protocol address */ u_char ar_hln; /* length of hardware address */ u_char ar_pln; /* length of protocol address */ u_short ar_op; /* one of: */ #define ARPOP_REQUEST 1 /* request to resolve address */ #define ARPOP_REPLY 2 /* response to previous request */ #define ARPOP_REVREQUEST 3 /* request protocol address given hardware */ #define ARPOP_REVREPLY 4 /* response giving protocol address */ #define ARPOP_INVREQUEST 8 /* request to identify peer */ #define ARPOP_INVREPLY 9 /* response identifying peer */ #define ARPOP_NAK 10 /* NAK - only valif for ATM ARP */ /* * The remaining fields are variable in size, * according to the sizes above. */ #ifdef COMMENT_ONLY u_char ar_sha[]; /* sender hardware address */ u_char ar_spa[]; /* sender protocol address */ u_char ar_tha[]; /* target hardware address */ u_char ar_tpa[]; /* target protocol address */ #endif #define ar_sha(ap) (((const u_char *)((ap)+1))+0) #define ar_spa(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln) #define ar_tha(ap) (((const u_char *)((ap)+1))+ (ap)->ar_hln+(ap)->ar_pln) #define ar_tpa(ap) (((const u_char *)((ap)+1))+2*(ap)->ar_hln+(ap)->ar_pln) }; #define ARP_HDRLEN 8 #define HRD(ap) EXTRACT_16BITS(&(ap)->ar_hrd) #define HRD_LEN(ap) ((ap)->ar_hln) #define PROTO_LEN(ap) ((ap)->ar_pln) #define OP(ap) EXTRACT_16BITS(&(ap)->ar_op) #define PRO(ap) EXTRACT_16BITS(&(ap)->ar_pro) #define SHA(ap) (ar_sha(ap)) #define SPA(ap) (ar_spa(ap)) #define THA(ap) (ar_tha(ap)) #define TPA(ap) (ar_tpa(ap)) static const struct tok arpop_values[] = { { ARPOP_REQUEST, "Request" }, { ARPOP_REPLY, "Reply" }, { ARPOP_REVREQUEST, "Reverse Request" }, { ARPOP_REVREPLY, "Reverse Reply" }, { ARPOP_INVREQUEST, "Inverse Request" }, { ARPOP_INVREPLY, "Inverse Reply" }, { ARPOP_NAK, "NACK Reply" }, { 0, NULL } }; static const struct tok arphrd_values[] = { { ARPHRD_ETHER, "Ethernet" }, { ARPHRD_IEEE802, "TokenRing" }, { ARPHRD_ARCNET, "ArcNet" }, { ARPHRD_FRELAY, "FrameRelay" }, { ARPHRD_STRIP, "Strip" }, { ARPHRD_IEEE1394, "IEEE 1394" }, { ARPHRD_ATM2225, "ATM" }, { 0, NULL } }; /* * ATM Address Resolution Protocol. * * See RFC 2225 for protocol description. ATMARP packets are similar * to ARP packets, except that there are no length fields for the * protocol address - instead, there are type/length fields for * the ATM number and subaddress - and the hardware addresses consist * of an ATM number and an ATM subaddress. */ struct atmarp_pkthdr { u_short aar_hrd; /* format of hardware address */ u_short aar_pro; /* format of protocol address */ u_char aar_shtl; /* length of source ATM number */ u_char aar_sstl; /* length of source ATM subaddress */ #define ATMARP_IS_E164 0x40 /* bit in type/length for E.164 format */ #define ATMARP_LEN_MASK 0x3F /* length of {sub}address in type/length */ u_short aar_op; /* same as regular ARP */ u_char aar_spln; /* length of source protocol address */ u_char aar_thtl; /* length of target ATM number */ u_char aar_tstl; /* length of target ATM subaddress */ u_char aar_tpln; /* length of target protocol address */ /* * The remaining fields are variable in size, * according to the sizes above. */ #ifdef COMMENT_ONLY u_char aar_sha[]; /* source ATM number */ u_char aar_ssa[]; /* source ATM subaddress */ u_char aar_spa[]; /* sender protocol address */ u_char aar_tha[]; /* target ATM number */ u_char aar_tsa[]; /* target ATM subaddress */ u_char aar_tpa[]; /* target protocol address */ #endif #define ATMHRD(ap) EXTRACT_16BITS(&(ap)->aar_hrd) #define ATMSHRD_LEN(ap) ((ap)->aar_shtl & ATMARP_LEN_MASK) #define ATMSSLN(ap) ((ap)->aar_sstl & ATMARP_LEN_MASK) #define ATMSPROTO_LEN(ap) ((ap)->aar_spln) #define ATMOP(ap) EXTRACT_16BITS(&(ap)->aar_op) #define ATMPRO(ap) EXTRACT_16BITS(&(ap)->aar_pro) #define ATMTHRD_LEN(ap) ((ap)->aar_thtl & ATMARP_LEN_MASK) #define ATMTSLN(ap) ((ap)->aar_tstl & ATMARP_LEN_MASK) #define ATMTPROTO_LEN(ap) ((ap)->aar_tpln) #define aar_sha(ap) ((const u_char *)((ap)+1)) #define aar_ssa(ap) (aar_sha(ap) + ATMSHRD_LEN(ap)) #define aar_spa(ap) (aar_ssa(ap) + ATMSSLN(ap)) #define aar_tha(ap) (aar_spa(ap) + ATMSPROTO_LEN(ap)) #define aar_tsa(ap) (aar_tha(ap) + ATMTHRD_LEN(ap)) #define aar_tpa(ap) (aar_tsa(ap) + ATMTSLN(ap)) }; #define ATMSHA(ap) (aar_sha(ap)) #define ATMSSA(ap) (aar_ssa(ap)) #define ATMSPA(ap) (aar_spa(ap)) #define ATMTHA(ap) (aar_tha(ap)) #define ATMTSA(ap) (aar_tsa(ap)) #define ATMTPA(ap) (aar_tpa(ap)) static u_char ezero[6]; static void atmarp_addr_print(netdissect_options *ndo, const u_char *ha, u_int ha_len, const u_char *srca, u_int srca_len) { if (ha_len == 0) ND_PRINT((ndo, "")); else { ND_PRINT((ndo, "%s", linkaddr_string(ha, LINKADDR_ATM, ha_len))); if (srca_len != 0) ND_PRINT((ndo, ",%s", linkaddr_string(srca, LINKADDR_ATM, srca_len))); } } static void atmarp_print(netdissect_options *ndo, const u_char *bp, u_int length, u_int caplen) { const struct atmarp_pkthdr *ap; u_short pro, hrd, op; ap = (const struct atmarp_pkthdr *)bp; ND_TCHECK(*ap); hrd = ATMHRD(ap); pro = ATMPRO(ap); op = ATMOP(ap); if (!ND_TTEST2(*aar_tpa(ap), ATMTPROTO_LEN(ap))) { ND_PRINT((ndo, "[|ARP]")); ND_DEFAULTPRINT((const u_char *)ap, length); return; } if (!ndo->ndo_eflag) { ND_PRINT((ndo, "ARP, ")); } if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || ATMSPROTO_LEN(ap) != 4 || ATMTPROTO_LEN(ap) != 4 || ndo->ndo_vflag) { ND_PRINT((ndo, "%s, %s (len %u/%u)", tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), ATMSPROTO_LEN(ap), ATMTPROTO_LEN(ap))); /* don't know know about the address formats */ if (!ndo->ndo_vflag) { goto out; } } /* print operation */ printf("%s%s ", ndo->ndo_vflag ? ", " : "", tok2str(arpop_values, "Unknown (%u)", op)); switch (op) { case ARPOP_REQUEST: ND_PRINT((ndo, "who-has %s", ipaddr_string(ATMTPA(ap)))); if (ATMTHRD_LEN(ap) != 0) { ND_PRINT((ndo, " (")); atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), ATMTSA(ap), ATMTSLN(ap)); ND_PRINT((ndo, ")")); } ND_PRINT((ndo, "tell %s", ipaddr_string(ATMSPA(ap)))); break; case ARPOP_REPLY: ND_PRINT((ndo, "%s is-at ", ipaddr_string(ATMSPA(ap)))); atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), ATMSSLN(ap)); break; case ARPOP_INVREQUEST: ND_PRINT((ndo, "who-is ")); atmarp_addr_print(ndo, ATMTHA(ap), ATMTHRD_LEN(ap), ATMTSA(ap), ATMTSLN(ap)); ND_PRINT((ndo, " tell ")); atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), ATMSSLN(ap)); break; case ARPOP_INVREPLY: atmarp_addr_print(ndo, ATMSHA(ap), ATMSHRD_LEN(ap), ATMSSA(ap), ATMSSLN(ap)); ND_PRINT((ndo, "at %s", ipaddr_string(ATMSPA(ap)))); break; case ARPOP_NAK: ND_PRINT((ndo, "for %s", ipaddr_string(ATMSPA(ap)))); break; default: ND_DEFAULTPRINT((const u_char *)ap, caplen); return; } out: ND_PRINT((ndo, ", length %u", length)); return; trunc: ND_PRINT((ndo, "[|ARP]")); } void arp_print(netdissect_options *ndo, const u_char *bp, u_int length, u_int caplen) { const struct arp_pkthdr *ap; u_short pro, hrd, op, linkaddr; ap = (const struct arp_pkthdr *)bp; ND_TCHECK(*ap); hrd = HRD(ap); pro = PRO(ap); op = OP(ap); /* if its ATM then call the ATM ARP printer for Frame-relay ARP most of the fields are similar to Ethernet so overload the Ethernet Printer and set the linkaddr type for linkaddr_string() accordingly */ switch(hrd) { case ARPHRD_ATM2225: atmarp_print(ndo, bp, length, caplen); return; case ARPHRD_FRELAY: linkaddr = LINKADDR_FRELAY; break; default: linkaddr = LINKADDR_ETHER; break; } if (!ND_TTEST2(*ar_tpa(ap), PROTO_LEN(ap))) { ND_PRINT((ndo, "[|ARP]")); ND_DEFAULTPRINT((const u_char *)ap, length); return; } if (!ndo->ndo_eflag) { ND_PRINT((ndo, "ARP, ")); } /* print hardware type/len and proto type/len */ if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) || PROTO_LEN(ap) != 4 || HRD_LEN(ap) == 0 || ndo->ndo_vflag) { ND_PRINT((ndo, "%s (len %u), %s (len %u)", tok2str(arphrd_values, "Unknown Hardware (%u)", hrd), HRD_LEN(ap), tok2str(ethertype_values, "Unknown Protocol (0x%04x)", pro), PROTO_LEN(ap))); /* don't know know about the address formats */ if (!ndo->ndo_vflag) { goto out; } } /* print operation */ printf("%s%s ", ndo->ndo_vflag ? ", " : "", tok2str(arpop_values, "Unknown (%u)", op)); switch (op) { case ARPOP_REQUEST: ND_PRINT((ndo, "who-has %s", ipaddr_string(TPA(ap)))); if (memcmp((const char *)ezero, (const char *)THA(ap), HRD_LEN(ap)) != 0) ND_PRINT((ndo, " (%s)", linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)))); ND_PRINT((ndo, " tell %s", ipaddr_string(SPA(ap)))); break; case ARPOP_REPLY: ND_PRINT((ndo, "%s is-at %s", ipaddr_string(SPA(ap)), linkaddr_string(SHA(ap), linkaddr, HRD_LEN(ap)))); break; case ARPOP_REVREQUEST: ND_PRINT((ndo, "who-is %s tell %s", linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), linkaddr_string(SHA(ap), linkaddr, HRD_LEN(ap)))); break; case ARPOP_REVREPLY: ND_PRINT((ndo, "%s at %s", linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), ipaddr_string(TPA(ap)))); break; case ARPOP_INVREQUEST: ND_PRINT((ndo, "who-is %s tell %s", linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), linkaddr_string(SHA(ap), linkaddr, HRD_LEN(ap)))); break; case ARPOP_INVREPLY: ND_PRINT((ndo,"%s at %s", linkaddr_string(THA(ap), linkaddr, HRD_LEN(ap)), ipaddr_string(TPA(ap)))); break; default: ND_DEFAULTPRINT((const u_char *)ap, caplen); return; } out: ND_PRINT((ndo, ", length %u", length)); return; trunc: ND_PRINT((ndo, "[|ARP]")); } /* * Local Variables: * c-style: bsd * End: */