The Tcpdump Group git mirrors - tcpdump/blob - print-token.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
   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  * Hacked version of print-ether.c  Larry Lile <lile@stdio.com>
  22  *
  23  * Further tweaked to more closely resemble print-fddi.c
  24  *      Guy Harris <guy@alum.mit.edu>
  25  */
  26 #ifndef lint
  27 static const char rcsid[] =
  28     "@(#) $Header: /tcpdump/master/tcpdump/print-token.c,v 1.15 2002-05-29 10:06:27 guy Exp $";
  29 #endif
  30
  31 #ifdef HAVE_CONFIG_H
  32 #include "config.h"
  33 #endif
  34
  35 #include <sys/param.h>
  36 #include <sys/time.h>
  37 #include <sys/socket.h>
  38
  39 #include <netinet/in.h>
  40
  41 #include <pcap.h>
  42 #include <stdio.h>
  43 #include <string.h>
  44
  45 #include "interface.h"
  46 #include "addrtoname.h"
  47 #include "ethertype.h"
  48
  49 #include "ether.h"
  50 #include "token.h"
  51
  52 /* Extract src, dst addresses */
  53 static inline void
  54 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
  55 {
  56         memcpy(fdst, (const char *)trp->token_dhost, 6);
  57         memcpy(fsrc, (const char *)trp->token_shost, 6);
  58 }
  59
  60 /*
  61  * Print the TR MAC header
  62  */
  63 static inline void
  64 token_hdr_print(register const struct token_header *trp, register u_int length,
  65            register const u_char *fsrc, register const u_char *fdst)
  66 {
  67         const char *srcname, *dstname;
  68
  69         srcname = etheraddr_string(fsrc);
  70         dstname = etheraddr_string(fdst);
  71
  72         if (vflag)
  73                 (void) printf("%02x %02x %s %s %d: ",
  74                        trp->token_ac,
  75                        trp->token_fc,
  76                        srcname, dstname,
  77                        length);
  78         else
  79                 printf("%s %s %d: ", srcname, dstname, length);
  80 }
  81
  82 static const char *broadcast_indicator[] = {
  83         "Non-Broadcast", "Non-Broadcast",
  84         "Non-Broadcast", "Non-Broadcast",
  85         "All-routes",    "All-routes",
  86         "Single-route",  "Single-route"
  87 };
  88
  89 static const char *direction[] = {
  90         "Forward", "Backward"
  91 };
  92
  93 static const char *largest_frame[] = {
  94         "516",
  95         "1500",
  96         "2052",
  97         "4472",
  98         "8144",
  99         "11407",
 100         "17800",
 101         "??"
 102 };
 103
 104 u_int
 105 token_print(const u_char *p, u_int length, u_int caplen)
 106 {
 107         const struct token_header *trp;
 108         u_short extracted_ethertype;
 109         struct ether_header ehdr;
 110         u_int route_len = 0, hdr_len = TOKEN_HDRLEN, seg;
 111
 112         trp = (const struct token_header *)p;
 113
 114         if (caplen < TOKEN_HDRLEN) {
 115                 printf("[|token-ring]");
 116                 return hdr_len;
 117         }
 118         /*
 119          * Get the TR addresses into a canonical form
 120          */
 121         extract_token_addrs(trp, (char*)ESRC(&ehdr), (char*)EDST(&ehdr));
 122         /*
 123          * Some printers want to get back at the ethernet addresses,
 124          * and/or check that they're not walking off the end of the packet.
 125          * Rather than pass them all the way down, we set these globals.
 126          */
 127         snapend = p + caplen;
 128         /*
 129          * Actually, the only printers that use packetp are print-arp.c
 130          * and print-bootp.c, and they assume that packetp points to an
 131          * Ethernet header.  The right thing to do is to fix them to know
 132          * which link type is in use when they excavate. XXX
 133          */
 134         packetp = (u_char *)&ehdr;
 135
 136         /* Adjust for source routing information in the MAC header */
 137         if (IS_SOURCE_ROUTED(trp)) {
 138                 /* Clear source-routed bit */
 139                 *ESRC(&ehdr) &= 0x7f;
 140
 141                 if (eflag)
 142                         token_hdr_print(trp, length, ESRC(&ehdr), EDST(&ehdr));
 143
 144                 route_len = RIF_LENGTH(trp);
 145                 if (vflag) {
 146                         printf("%s ", broadcast_indicator[BROADCAST(trp)]);
 147                         printf("%s", direction[DIRECTION(trp)]);
 148
 149                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 150                                 printf(" [%d:%d]", RING_NUMBER(trp, seg),
 151                                     BRIDGE_NUMBER(trp, seg));
 152                 } else {
 153                         printf("rt = %x", ntohs(trp->token_rcf));
 154
 155                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 156                                 printf(":%x", ntohs(trp->token_rseg[seg]));
 157                 }
 158                 printf(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
 159         } else {
 160                 if (eflag)
 161                         token_hdr_print(trp, length, ESRC(&ehdr), EDST(&ehdr));
 162         }
 163
 164         /* Skip over token ring MAC header and routing information */
 165         hdr_len += route_len;
 166         length -= hdr_len;
 167         p += hdr_len;
 168         caplen -= hdr_len;
 169
 170         /* Frame Control field determines interpretation of packet */
 171         extracted_ethertype = 0;
 172         if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
 173                 /* Try to print the LLC-layer header & higher layers */
 174                 if (llc_print(p, length, caplen, ESRC(&ehdr), EDST(&ehdr),
 175                     &extracted_ethertype) == 0) {
 176                         /* ether_type not known, print raw packet */
 177                         if (!eflag)
 178                                 token_hdr_print(trp,
 179                                     length + TOKEN_HDRLEN + route_len,
 180                                     ESRC(&ehdr), EDST(&ehdr));
 181                         if (extracted_ethertype) {
 182                                 printf("(LLC %s) ",
 183                         etherproto_string(htons(extracted_ethertype)));
 184                         }
 185                         if (!xflag && !qflag)
 186                                 default_print(p, caplen);
 187                 }
 188         } else {
 189                 /* Some kinds of TR packet we cannot handle intelligently */
 190                 /* XXX - dissect MAC packets if frame type is 0 */
 191                 if (!eflag)
 192                         token_hdr_print(trp, length + TOKEN_HDRLEN + route_len,
 193                             ESRC(&ehdr), EDST(&ehdr));
 194                 if (!xflag && !qflag)
 195                         default_print(p, caplen);
 196         }
 197         return (hdr_len);
 198 }
 199
 200 /*
 201  * This is the top level routine of the printer.  'p' is the points
 202  * to the TR header of the packet, 'tvp' is the timestamp,
 203  * 'length' is the length of the packet off the wire, and 'caplen'
 204  * is the number of bytes actually captured.
 205  */
 206 void
 207 token_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
 208 {
 209         u_int caplen = h->caplen;
 210         u_int length = h->len;
 211         u_int hdr_len;
 212
 213         ++infodelay;
 214         ts_print(&h->ts);
 215
 216         hdr_len = token_print(p, length, caplen);
 217
 218         /*
 219          * If "-x" was specified, print stuff past the Token Ring header,
 220          * if there's anything to print.
 221          */
 222         if (xflag && caplen > hdr_len)
 223                 default_print(p + hdr_len, caplen - hdr_len);
 224
 225         putchar('\n');
 226
 227         --infodelay;
 228         if (infoprint)
 229                 info(0);
 230 }