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