1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 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-sll.c,v 1.19 2005-11-13 12:12:43 guy 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 <string.h> 34 #include <pcap.h> 35 36 #include "interface.h" 37 #include "addrtoname.h" 38 #include "ethertype.h" 39 #include "extract.h" 40 41 #include "ether.h" 42 #include "sll.h" 43 44 static const struct tok sll_pkttype_values[] = { 45 { LINUX_SLL_HOST, "In" }, 46 { LINUX_SLL_BROADCAST, "B" }, 47 { LINUX_SLL_MULTICAST, "M" }, 48 { LINUX_SLL_OTHERHOST, "P" }, 49 { LINUX_SLL_OUTGOING, "Out" }, 50 { 0, NULL} 51 }; 52 53 static inline void 54 sll_print(register const struct sll_header *sllp, u_int length) 55 { 56 u_short ether_type; 57 58 printf("%3s ",tok2str(sll_pkttype_values,"?",EXTRACT_16BITS(&sllp->sll_pkttype))); 59 60 /* 61 * XXX - check the link-layer address type value? 62 * For now, we just assume 6 means Ethernet. 63 * XXX - print others as strings of hex? 64 */ 65 if (EXTRACT_16BITS(&sllp->sll_halen) == 6) 66 (void)printf("%s ", etheraddr_string(sllp->sll_addr)); 67 68 if (!qflag) { 69 ether_type = EXTRACT_16BITS(&sllp->sll_protocol); 70 71 if (ether_type <= ETHERMTU) { 72 /* 73 * Not an Ethernet type; what type is it? 74 */ 75 switch (ether_type) { 76 77 case LINUX_SLL_P_802_3: 78 /* 79 * Ethernet_802.3 IPX frame. 80 */ 81 (void)printf("802.3"); 82 break; 83 84 case LINUX_SLL_P_802_2: 85 /* 86 * 802.2. 87 */ 88 (void)printf("802.2"); 89 break; 90 91 default: 92 /* 93 * What is it? 94 */ 95 (void)printf("ethertype Unknown (0x%04x)", 96 ether_type); 97 break; 98 } 99 } else { 100 (void)printf("ethertype %s (0x%04x)", 101 tok2str(ethertype_values, "Unknown", ether_type), 102 ether_type); 103 } 104 (void)printf(", length %u: ", length); 105 } 106 } 107 108 /* 109 * This is the top level routine of the printer. 'p' points to the 110 * Linux "cooked capture" header of the packet, 'h->ts' is the timestamp, 111 * 'h->len' is the length of the packet off the wire, and 'h->caplen' 112 * is the number of bytes actually captured. 113 */ 114 u_int 115 sll_if_print(const struct pcap_pkthdr *h, const u_char *p) 116 { 117 u_int caplen = h->caplen; 118 u_int length = h->len; 119 register const struct sll_header *sllp; 120 u_short ether_type; 121 u_short extracted_ethertype; 122 123 if (caplen < SLL_HDR_LEN) { 124 /* 125 * XXX - this "can't happen" because "pcap-linux.c" always 126 * adds this many bytes of header to every packet in a 127 * cooked socket capture. 128 */ 129 printf("[|sll]"); 130 return (caplen); 131 } 132 133 sllp = (const struct sll_header *)p; 134 135 if (eflag) 136 sll_print(sllp, length); 137 138 /* 139 * Go past the cooked-mode header. 140 */ 141 length -= SLL_HDR_LEN; 142 caplen -= SLL_HDR_LEN; 143 p += SLL_HDR_LEN; 144 145 ether_type = EXTRACT_16BITS(&sllp->sll_protocol); 146 147 recurse: 148 /* 149 * Is it (gag) an 802.3 encapsulation, or some non-Ethernet 150 * packet type? 151 */ 152 if (ether_type <= ETHERMTU) { 153 /* 154 * Yes - what type is it? 155 */ 156 switch (ether_type) { 157 158 case LINUX_SLL_P_802_3: 159 /* 160 * Ethernet_802.3 IPX frame. 161 */ 162 ipx_print(p, length); 163 break; 164 165 case LINUX_SLL_P_802_2: 166 /* 167 * 802.2. 168 * Try to print the LLC-layer header & higher layers. 169 */ 170 if (llc_print(p, length, caplen, NULL, NULL, 171 &extracted_ethertype) == 0) 172 goto unknown; /* unknown LLC type */ 173 break; 174 175 default: 176 extracted_ethertype = 0; 177 /*FALLTHROUGH*/ 178 179 unknown: 180 /* ether_type not known, print raw packet */ 181 if (!eflag) 182 sll_print(sllp, length + SLL_HDR_LEN); 183 if (extracted_ethertype) { 184 printf("(LLC %s) ", 185 etherproto_string(htons(extracted_ethertype))); 186 } 187 if (!suppress_default_print) 188 default_print(p, caplen); 189 break; 190 } 191 } else if (ether_type == ETHERTYPE_8021Q) { 192 /* 193 * Print VLAN information, and then go back and process 194 * the enclosed type field. 195 */ 196 if (caplen < 4 || length < 4) { 197 printf("[|vlan]"); 198 return (SLL_HDR_LEN); 199 } 200 if (eflag) { 201 u_int16_t tag = EXTRACT_16BITS(p); 202 203 printf("vlan %u, p %u%s, ", 204 tag & 0xfff, 205 tag >> 13, 206 (tag & 0x1000) ? ", CFI" : ""); 207 } 208 209 ether_type = EXTRACT_16BITS(p + 2); 210 if (ether_type <= ETHERMTU) 211 ether_type = LINUX_SLL_P_802_2; 212 if (!qflag) { 213 (void)printf("ethertype %s, ", 214 tok2str(ethertype_values, "Unknown", ether_type)); 215 } 216 p += 4; 217 length -= 4; 218 caplen -= 4; 219 goto recurse; 220 } else { 221 if (ethertype_print(gndo, ether_type, p, length, caplen) == 0) { 222 /* ether_type not known, print raw packet */ 223 if (!eflag) 224 sll_print(sllp, length + SLL_HDR_LEN); 225 if (!suppress_default_print) 226 default_print(p, caplen); 227 } 228 } 229 230 return (SLL_HDR_LEN); 231 } 232