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 1.20 2002-12-18 08:53:24 guy Exp $";
  29 #endif
  30
  31 #ifdef HAVE_CONFIG_H
  32 #include "config.h"
  33 #endif
  34
  35 #include <tcpdump-stdinc.h>
  36
  37 #include <pcap.h>
  38 #include <stdio.h>
  39 #include <string.h>
  40
  41 #include "interface.h"
  42 #include "addrtoname.h"
  43 #include "ethertype.h"
  44
  45 #include "ether.h"
  46 #include "token.h"
  47
  48 /* Extract src, dst addresses */
  49 static inline void
  50 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
  51 {
  52         memcpy(fdst, (const char *)trp->token_dhost, 6);
  53         memcpy(fsrc, (const char *)trp->token_shost, 6);
  54 }
  55
  56 /*
  57  * Print the TR MAC header
  58  */
  59 static inline void
  60 token_hdr_print(register const struct token_header *trp, register u_int length,
  61            register const u_char *fsrc, register const u_char *fdst)
  62 {
  63         const char *srcname, *dstname;
  64
  65         srcname = etheraddr_string(fsrc);
  66         dstname = etheraddr_string(fdst);
  67
  68         if (vflag)
  69                 (void) printf("%02x %02x %s %s %d: ",
  70                        trp->token_ac,
  71                        trp->token_fc,
  72                        srcname, dstname,
  73                        length);
  74         else
  75                 printf("%s %s %d: ", srcname, dstname, length);
  76 }
  77
  78 static const char *broadcast_indicator[] = {
  79         "Non-Broadcast", "Non-Broadcast",
  80         "Non-Broadcast", "Non-Broadcast",
  81         "All-routes",    "All-routes",
  82         "Single-route",  "Single-route"
  83 };
  84
  85 static const char *direction[] = {
  86         "Forward", "Backward"
  87 };
  88
  89 static const char *largest_frame[] = {
  90         "516",
  91         "1500",
  92         "2052",
  93         "4472",
  94         "8144",
  95         "11407",
  96         "17800",
  97         "??"
  98 };
  99
 100 u_int
 101 token_print(const u_char *p, u_int length, u_int caplen)
 102 {
 103         const struct token_header *trp;
 104         u_short extracted_ethertype;
 105         struct ether_header ehdr;
 106         u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
 107         int seg;
 108
 109         trp = (const struct token_header *)p;
 110
 111         if (caplen < TOKEN_HDRLEN) {
 112                 printf("[|token-ring]");
 113                 return hdr_len;
 114         }
 115
 116         /*
 117          * Get the TR addresses into a canonical form
 118          */
 119         extract_token_addrs(trp, (char*)ESRC(&ehdr), (char*)EDST(&ehdr));
 120
 121         /*
 122          * Some printers want to check that they're not walking off the
 123          * end of the packet.
 124          * Rather than pass it all the way down, we set this global.
 125          */
 126         snapend = p + caplen;
 127
 128         /* Adjust for source routing information in the MAC header */
 129         if (IS_SOURCE_ROUTED(trp)) {
 130                 /* Clear source-routed bit */
 131                 *ESRC(&ehdr) &= 0x7f;
 132
 133                 if (eflag)
 134                         token_hdr_print(trp, length, ESRC(&ehdr), EDST(&ehdr));
 135
 136                 route_len = RIF_LENGTH(trp);
 137                 if (vflag) {
 138                         printf("%s ", broadcast_indicator[BROADCAST(trp)]);
 139                         printf("%s", direction[DIRECTION(trp)]);
 140
 141                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 142                                 printf(" [%d:%d]", RING_NUMBER(trp, seg),
 143                                     BRIDGE_NUMBER(trp, seg));
 144                 } else {
 145                         printf("rt = %x", ntohs(trp->token_rcf));
 146
 147                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 148                                 printf(":%x", ntohs(trp->token_rseg[seg]));
 149                 }
 150                 printf(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
 151         } else {
 152                 if (eflag)
 153                         token_hdr_print(trp, length, ESRC(&ehdr), EDST(&ehdr));
 154         }
 155
 156         /* Skip over token ring MAC header and routing information */
 157         hdr_len += route_len;
 158         length -= hdr_len;
 159         p += hdr_len;
 160         caplen -= hdr_len;
 161
 162         /* Frame Control field determines interpretation of packet */
 163         extracted_ethertype = 0;
 164         if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
 165                 /* Try to print the LLC-layer header & higher layers */
 166                 if (llc_print(p, length, caplen, ESRC(&ehdr), EDST(&ehdr),
 167                     &extracted_ethertype) == 0) {
 168                         /* ether_type not known, print raw packet */
 169                         if (!eflag)
 170                                 token_hdr_print(trp,
 171                                     length + TOKEN_HDRLEN + route_len,
 172                                     ESRC(&ehdr), EDST(&ehdr));
 173                         if (extracted_ethertype) {
 174                                 printf("(LLC %s) ",
 175                         etherproto_string(htons(extracted_ethertype)));
 176                         }
 177                         if (!xflag && !qflag)
 178                                 default_print(p, caplen);
 179                 }
 180         } else {
 181                 /* Some kinds of TR packet we cannot handle intelligently */
 182                 /* XXX - dissect MAC packets if frame type is 0 */
 183                 if (!eflag)
 184                         token_hdr_print(trp, length + TOKEN_HDRLEN + route_len,
 185                             ESRC(&ehdr), EDST(&ehdr));
 186                 if (!xflag && !qflag)
 187                         default_print(p, caplen);
 188         }
 189         return (hdr_len);
 190 }
 191
 192 /*
 193  * This is the top level routine of the printer.  'p' points
 194  * to the TR header of the packet, 'h->ts' is the timestamp,
 195  * 'h->length' is the length of the packet off the wire, and 'h->caplen'
 196  * is the number of bytes actually captured.
 197  */
 198 void
 199 token_if_print(u_char *user _U_, const struct pcap_pkthdr *h, const u_char *p)
 200 {
 201         u_int caplen = h->caplen;
 202         u_int length = h->len;
 203         u_int hdr_len;
 204
 205         ++infodelay;
 206         ts_print(&h->ts);
 207
 208         hdr_len = token_print(p, length, caplen);
 209
 210         /*
 211          * If "-x" was specified, print stuff past the Token Ring header,
 212          * if there's anything to print.
 213          */
 214         if (xflag && caplen > hdr_len)
 215                 default_print(p + hdr_len, caplen - hdr_len);
 216
 217         putchar('\n');
 218
 219         --infodelay;
 220         if (infoprint)
 221                 info(0);
 222 }