1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000 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 * $FreeBSD$ 22 */ 23 #ifndef lint 24 static const char rcsid[] _U_ = 25 "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.82.2.3 2003/12/29 22:42:21 hannes Exp $ (LBL)"; 26 #endif 27 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <tcpdump-stdinc.h> 33 34 #include <stdio.h> 35 #include <pcap.h> 36 37 #include "interface.h" 38 #include "addrtoname.h" 39 #include "ethertype.h" 40 41 #include "ether.h" 42 43 const u_char *snapend; 44 45 const struct tok ethertype_values[] = { 46 { ETHERTYPE_IP, "IPv4" }, 47 { ETHERTYPE_MPLS, "MPLS unicast" }, 48 { ETHERTYPE_MPLS_MULTI, "MPLS multicast" }, 49 { ETHERTYPE_IPV6, "IPv6" }, 50 { ETHERTYPE_8021Q, "802.1Q" }, 51 { ETHERTYPE_VMAN, "VMAN" }, 52 { ETHERTYPE_PUP, "PUP" }, 53 { ETHERTYPE_ARP, "ARP"}, 54 { ETHERTYPE_REVARP , "Reverse ARP"}, 55 { ETHERTYPE_NS, "NS" }, 56 { ETHERTYPE_SPRITE, "Sprite" }, 57 { ETHERTYPE_TRAIL, "Trail" }, 58 { ETHERTYPE_MOPDL, "MOP DL" }, 59 { ETHERTYPE_MOPRC, "MOP RC" }, 60 { ETHERTYPE_DN, "DN" }, 61 { ETHERTYPE_LAT, "LAT" }, 62 { ETHERTYPE_SCA, "SCA" }, 63 { ETHERTYPE_LANBRIDGE, "Lanbridge" }, 64 { ETHERTYPE_DECDNS, "DEC DNS" }, 65 { ETHERTYPE_DECDTS, "DEC DTS" }, 66 { ETHERTYPE_VEXP, "VEXP" }, 67 { ETHERTYPE_VPROD, "VPROD" }, 68 { ETHERTYPE_ATALK, "Appletalk" }, 69 { ETHERTYPE_AARP, "Appletalk ARP" }, 70 { ETHERTYPE_IPX, "IPX" }, 71 { ETHERTYPE_PPP, "PPP" }, 72 { ETHERTYPE_PPPOED, "PPPoE D" }, 73 { ETHERTYPE_PPPOES, "PPPoE S" }, 74 { ETHERTYPE_LOOPBACK, "Loopback" }, 75 { 0, NULL} 76 }; 77 78 static inline void 79 ether_hdr_print(register const u_char *bp, u_int length) 80 { 81 register const struct ether_header *ep; 82 ep = (const struct ether_header *)bp; 83 84 (void)printf("%s > %s", 85 etheraddr_string(ESRC(ep)), 86 etheraddr_string(EDST(ep))); 87 88 if (!qflag) { 89 if (ntohs(ep->ether_type) <= ETHERMTU) 90 (void)printf(", 802.3"); 91 else 92 (void)printf(", ethertype %s (0x%04x)", 93 tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)), 94 ntohs(ep->ether_type)); 95 } else { 96 if (ntohs(ep->ether_type) <= ETHERMTU) 97 (void)printf(", 802.3"); 98 else 99 (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type))); 100 } 101 102 (void)printf(", length %u: ", length); 103 } 104 105 void 106 ether_print(const u_char *p, u_int length, u_int caplen) 107 { 108 struct ether_header *ep; 109 u_short ether_type; 110 u_short extracted_ether_type; 111 112 if (caplen < ETHER_HDRLEN) { 113 printf("[|ether]"); 114 return; 115 } 116 117 if (eflag) 118 ether_hdr_print(p, length); 119 120 length -= ETHER_HDRLEN; 121 caplen -= ETHER_HDRLEN; 122 ep = (struct ether_header *)p; 123 p += ETHER_HDRLEN; 124 125 ether_type = ntohs(ep->ether_type); 126 127 /* 128 * Is it (gag) an 802.3 encapsulation? 129 */ 130 extracted_ether_type = 0; 131 if (ether_type <= ETHERMTU) { 132 /* Try to print the LLC-layer header & higher layers */ 133 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep), 134 &extracted_ether_type) == 0) { 135 /* ether_type not known, print raw packet */ 136 if (!eflag) 137 ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN); 138 139 if (!xflag && !qflag) 140 default_print(p, caplen); 141 } 142 } else if (ether_encap_print(ether_type, p, length, caplen, 143 &extracted_ether_type) == 0) { 144 /* ether_type not known, print raw packet */ 145 if (!eflag) 146 ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN); 147 148 if (!xflag && !qflag) 149 default_print(p, caplen); 150 } 151 } 152 153 /* 154 * This is the top level routine of the printer. 'p' points 155 * to the ether header of the packet, 'h->ts' is the timestamp, 156 * 'h->length' is the length of the packet off the wire, and 'h->caplen' 157 * is the number of bytes actually captured. 158 */ 159 u_int 160 ether_if_print(const struct pcap_pkthdr *h, const u_char *p) 161 { 162 ether_print(p, h->len, h->caplen); 163 164 return (ETHER_HDRLEN); 165 } 166 167 /* 168 * Prints the packet encapsulated in an Ethernet data segment 169 * (or an equivalent encapsulation), given the Ethernet type code. 170 * 171 * Returns non-zero if it can do so, zero if the ethertype is unknown. 172 * 173 * The Ethernet type code is passed through a pointer; if it was 174 * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of 175 * the 802.1Q payload, for the benefit of lower layers that might 176 * want to know what it is. 177 */ 178 179 int 180 ether_encap_print(u_short ether_type, const u_char *p, 181 u_int length, u_int caplen, u_short *extracted_ether_type) 182 { 183 recurse: 184 *extracted_ether_type = ether_type; 185 186 switch (ether_type) { 187 188 case ETHERTYPE_IP: 189 ip_print(p, length); 190 return (1); 191 192 #ifdef INET6 193 case ETHERTYPE_IPV6: 194 ip6_print(p, length); 195 return (1); 196 #endif /*INET6*/ 197 198 case ETHERTYPE_ARP: 199 case ETHERTYPE_REVARP: 200 arp_print(p, length, caplen); 201 return (1); 202 203 case ETHERTYPE_DN: 204 decnet_print(p, length, caplen); 205 return (1); 206 207 case ETHERTYPE_ATALK: 208 if (vflag) 209 fputs("et1 ", stdout); 210 atalk_print(p, length); 211 return (1); 212 213 case ETHERTYPE_AARP: 214 aarp_print(p, length); 215 return (1); 216 217 case ETHERTYPE_IPX: 218 printf("(NOV-ETHII) "); 219 ipx_print(p, length); 220 return (1); 221 222 case ETHERTYPE_8021Q: 223 if (eflag) 224 printf("vlan %u, p %u%s, ", 225 ntohs(*(u_int16_t *)p) & 0xfff, 226 ntohs(*(u_int16_t *)p) >> 13, 227 (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : ""); 228 229 ether_type = ntohs(*(u_int16_t *)(p + 2)); 230 p += 4; 231 length -= 4; 232 caplen -= 4; 233 234 if (ether_type > ETHERMTU) { 235 if (eflag) 236 printf("ethertype %s, ", 237 tok2str(ethertype_values,"0x%04x", ether_type)); 238 goto recurse; 239 } 240 241 *extracted_ether_type = 0; 242 243 if (llc_print(p, length, caplen, p - 18, p - 12, 244 extracted_ether_type) == 0) { 245 ether_hdr_print(p - 18, length + 4); 246 } 247 248 if (!xflag && !qflag) 249 default_print(p - 18, caplen + 4); 250 251 return (1); 252 253 case ETHERTYPE_PPPOED: 254 case ETHERTYPE_PPPOES: 255 case ETHERTYPE_PPPOED2: 256 case ETHERTYPE_PPPOES2: 257 pppoe_print(p, length); 258 return (1); 259 260 case ETHERTYPE_PPP: 261 if (length) { 262 printf(": "); 263 ppp_print(p, length); 264 } 265 return (1); 266 267 case ETHERTYPE_LOOPBACK: 268 return (0); 269 270 case ETHERTYPE_MPLS: 271 case ETHERTYPE_MPLS_MULTI: 272 mpls_print(p, length); 273 return (1); 274 275 case ETHERTYPE_LAT: 276 case ETHERTYPE_SCA: 277 case ETHERTYPE_MOPRC: 278 case ETHERTYPE_MOPDL: 279 /* default_print for now */ 280 default: 281 return (0); 282 } 283 } 284