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[] = 25 "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.65 2001/07/04 22:03:14 fenner Exp $ (LBL)"; 26 #endif 27 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <sys/param.h> 33 #include <sys/time.h> 34 #include <sys/socket.h> 35 36 struct mbuf; 37 struct rtentry; 38 39 #include <netinet/in.h> 40 41 #include <stdio.h> 42 #include <pcap.h> 43 44 #include "interface.h" 45 #include "addrtoname.h" 46 #include "ethertype.h" 47 48 #include "ether.h" 49 50 const u_char *packetp; 51 const u_char *snapend; 52 53 static inline void 54 ether_print(register const u_char *bp, u_int length) 55 { 56 register const struct ether_header *ep; 57 58 ep = (const struct ether_header *)bp; 59 if (qflag) 60 (void)printf("%s %s %d: ", 61 etheraddr_string(ESRC(ep)), 62 etheraddr_string(EDST(ep)), 63 length); 64 else 65 (void)printf("%s %s %s %d: ", 66 etheraddr_string(ESRC(ep)), 67 etheraddr_string(EDST(ep)), 68 etherproto_string(ep->ether_type), 69 length); 70 } 71 72 /* 73 * This is the top level routine of the printer. 'p' is the points 74 * to the ether header of the packet, 'h->tv' is the timestamp, 75 * 'h->length' is the length of the packet off the wire, and 'h->caplen' 76 * is the number of bytes actually captured. 77 */ 78 void 79 ether_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p) 80 { 81 u_int caplen = h->caplen; 82 u_int length = h->len; 83 struct ether_header *ep; 84 u_short ether_type; 85 u_short extracted_ethertype; 86 87 ++infodelay; 88 ts_print(&h->ts); 89 90 if (caplen < ETHER_HDRLEN) { 91 printf("[|ether]"); 92 goto out; 93 } 94 95 if (eflag) 96 ether_print(p, length); 97 98 /* 99 * Some printers want to get back at the ethernet addresses, 100 * and/or check that they're not walking off the end of the packet. 101 * Rather than pass them all the way down, we set these globals. 102 */ 103 packetp = p; 104 snapend = p + caplen; 105 106 length -= ETHER_HDRLEN; 107 caplen -= ETHER_HDRLEN; 108 ep = (struct ether_header *)p; 109 p += ETHER_HDRLEN; 110 111 ether_type = ntohs(ep->ether_type); 112 113 /* 114 * Is it (gag) an 802.3 encapsulation? 115 */ 116 extracted_ethertype = 0; 117 if (ether_type <= ETHERMTU) { 118 /* Try to print the LLC-layer header & higher layers */ 119 if (llc_print(p, length, caplen, ESRC(ep), EDST(ep), 120 &extracted_ethertype) == 0) { 121 /* ether_type not known, print raw packet */ 122 if (!eflag) 123 ether_print((u_char *)ep, length + ETHER_HDRLEN); 124 if (extracted_ethertype) { 125 printf("(LLC %s) ", 126 etherproto_string(htons(extracted_ethertype))); 127 } 128 if (!xflag && !qflag) 129 default_print(p, caplen); 130 } 131 } else if (ether_encap_print(ether_type, p, length, caplen, 132 &extracted_ethertype) == 0) { 133 /* ether_type not known, print raw packet */ 134 if (!eflag) 135 ether_print((u_char *)ep, length + ETHER_HDRLEN); 136 if (!xflag && !qflag) 137 default_print(p, caplen); 138 } 139 if (xflag) 140 default_print(p, caplen); 141 out: 142 putchar('\n'); 143 --infodelay; 144 if (infoprint) 145 info(0); 146 } 147 148 /* 149 * Prints the packet encapsulated in an Ethernet data segment 150 * (or an equivalent encapsulation), given the Ethernet type code. 151 * 152 * Returns non-zero if it can do so, zero if the ethertype is unknown. 153 * 154 * The Ethernet type code is passed through a pointer; if it was 155 * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of 156 * the 802.1Q payload, for the benefit of lower layers that might 157 * want to know what it is. 158 */ 159 160 int 161 ether_encap_print(u_short ethertype, const u_char *p, 162 u_int length, u_int caplen, u_short *extracted_ethertype) 163 { 164 recurse: 165 *extracted_ethertype = ethertype; 166 167 switch (ethertype) { 168 169 case ETHERTYPE_IP: 170 ip_print(p, length); 171 return (1); 172 173 #ifdef INET6 174 case ETHERTYPE_IPV6: 175 ip6_print(p, length); 176 return (1); 177 #endif /*INET6*/ 178 179 case ETHERTYPE_ARP: 180 case ETHERTYPE_REVARP: 181 arp_print(p, length, caplen); 182 return (1); 183 184 case ETHERTYPE_DN: 185 decnet_print(p, length, caplen); 186 return (1); 187 188 case ETHERTYPE_ATALK: 189 if (vflag) 190 fputs("et1 ", stdout); 191 atalk_print(p, length); 192 return (1); 193 194 case ETHERTYPE_AARP: 195 aarp_print(p, length); 196 return (1); 197 198 case ETHERTYPE_IPX: 199 ipx_print(p, length); 200 return (1); 201 202 case ETHERTYPE_8021Q: 203 printf("802.1Q vlan#%d P%d%s ", 204 ntohs(*(u_int16_t *)p) & 0xfff, 205 ntohs(*(u_int16_t *)p) >> 13, 206 (ntohs(*(u_int16_t *)p) & 0x1000) ? " CFI" : ""); 207 ethertype = ntohs(*(u_int16_t *)(p + 2)); 208 p += 4; 209 length -= 4; 210 caplen -= 4; 211 if (ethertype > ETHERMTU) 212 goto recurse; 213 214 *extracted_ethertype = 0; 215 216 if (llc_print(p, length, caplen, p - 18, p - 12, 217 extracted_ethertype) == 0) { 218 /* ether_type not known, print raw packet */ 219 if (!eflag) 220 ether_print(p - 18, length + 4); 221 if (*extracted_ethertype) { 222 printf("(LLC %s) ", 223 etherproto_string(htons(*extracted_ethertype))); 224 } 225 if (!xflag && !qflag) 226 default_print(p - 18, caplen + 4); 227 } 228 return (1); 229 230 case ETHERTYPE_PPPOED: 231 case ETHERTYPE_PPPOES: 232 case ETHERTYPE_PPPOED2: 233 case ETHERTYPE_PPPOES2: 234 pppoe_print(p, length); 235 return (1); 236 237 case ETHERTYPE_PPP: 238 printf("ppp"); 239 if (length) { 240 printf(": "); 241 ppp_print(p, length); 242 } 243 return (1); 244 245 case ETHERTYPE_MPLS: 246 case ETHERTYPE_MPLS_MULTI: 247 mpls_print(p, length); 248 return (1); 249 250 case ETHERTYPE_LAT: 251 case ETHERTYPE_SCA: 252 case ETHERTYPE_MOPRC: 253 case ETHERTYPE_MOPDL: 254 /* default_print for now */ 255 default: 256 return (0); 257 } 258 } 259