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
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <tcpdump-stdinc.h>
  32
  33 #include <string.h>
  34
  35 #include "interface.h"
  36 #include "extract.h"
  37 #include "addrtoname.h"
  38 #include "ether.h"
  39
  40 /*
  41  * Copyright (c) 1998, Larry Lile
  42  * All rights reserved.
  43  *
  44  * Redistribution and use in source and binary forms, with or without
  45  * modification, are permitted provided that the following conditions
  46  * are met:
  47  * 1. Redistributions of source code must retain the above copyright
  48  *    notice unmodified, this list of conditions, and the following
  49  *    disclaimer.
  50  * 2. Redistributions in binary form must reproduce the above copyright
  51  *    notice, this list of conditions and the following disclaimer in the
  52  *    documentation and/or other materials provided with the distribution.
  53  *
  54  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  64  * SUCH DAMAGE.
  65  *
  66  */
  67
  68 #define TOKEN_HDRLEN            14
  69 #define TOKEN_RING_MAC_LEN      6
  70 #define ROUTING_SEGMENT_MAX     16
  71 #define IS_SOURCE_ROUTED(trp)   ((trp)->token_shost[0] & 0x80)
  72 #define FRAME_TYPE(trp)         (((trp)->token_fc & 0xC0) >> 6)
  73 #define TOKEN_FC_LLC            1
  74
  75 #define BROADCAST(trp)          ((EXTRACT_16BITS(&(trp)->token_rcf) & 0xE000) >> 13)
  76 #define RIF_LENGTH(trp)         ((EXTRACT_16BITS(&(trp)->token_rcf) & 0x1f00) >> 8)
  77 #define DIRECTION(trp)          ((EXTRACT_16BITS(&(trp)->token_rcf) & 0x0080) >> 7)
  78 #define LARGEST_FRAME(trp)      ((EXTRACT_16BITS(&(trp)->token_rcf) & 0x0070) >> 4)
  79 #define RING_NUMBER(trp, x)     ((EXTRACT_16BITS(&(trp)->token_rseg[x]) & 0xfff0) >> 4)
  80 #define BRIDGE_NUMBER(trp, x)   ((EXTRACT_16BITS(&(trp)->token_rseg[x]) & 0x000f))
  81 #define SEGMENT_COUNT(trp)      ((int)((RIF_LENGTH(trp) - 2) / 2))
  82
  83 struct token_header {
  84         uint8_t  token_ac;
  85         uint8_t  token_fc;
  86         uint8_t  token_dhost[TOKEN_RING_MAC_LEN];
  87         uint8_t  token_shost[TOKEN_RING_MAC_LEN];
  88         uint16_t token_rcf;
  89         uint16_t token_rseg[ROUTING_SEGMENT_MAX];
  90 };
  91
  92 static const char tstr[] = "[|token-ring]";
  93
  94 /* Extract src, dst addresses */
  95 static inline void
  96 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
  97 {
  98         memcpy(fdst, (const char *)trp->token_dhost, 6);
  99         memcpy(fsrc, (const char *)trp->token_shost, 6);
 100 }
 101
 102 /*
 103  * Print the TR MAC header
 104  */
 105 static inline void
 106 token_hdr_print(netdissect_options *ndo,
 107                 register const struct token_header *trp, register u_int length,
 108                 register const u_char *fsrc, register const u_char *fdst)
 109 {
 110         const char *srcname, *dstname;
 111
 112         srcname = etheraddr_string(ndo, fsrc);
 113         dstname = etheraddr_string(ndo, fdst);
 114
 115         if (!ndo->ndo_qflag)
 116                 ND_PRINT((ndo, "%02x %02x ",
 117                        trp->token_ac,
 118                        trp->token_fc));
 119         ND_PRINT((ndo, "%s > %s, length %u: ",
 120                srcname, dstname,
 121                length));
 122 }
 123
 124 static const char *broadcast_indicator[] = {
 125         "Non-Broadcast", "Non-Broadcast",
 126         "Non-Broadcast", "Non-Broadcast",
 127         "All-routes",    "All-routes",
 128         "Single-route",  "Single-route"
 129 };
 130
 131 static const char *direction[] = {
 132         "Forward", "Backward"
 133 };
 134
 135 static const char *largest_frame[] = {
 136         "516",
 137         "1500",
 138         "2052",
 139         "4472",
 140         "8144",
 141         "11407",
 142         "17800",
 143         "??"
 144 };
 145
 146 u_int
 147 token_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
 148 {
 149         const struct token_header *trp;
 150         int llc_hdrlen;
 151         struct ether_header ehdr;
 152         u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
 153         int seg;
 154
 155         trp = (const struct token_header *)p;
 156
 157         if (caplen < TOKEN_HDRLEN) {
 158                 ND_PRINT((ndo, "%s", tstr));
 159                 return hdr_len;
 160         }
 161
 162         /*
 163          * Get the TR addresses into a canonical form
 164          */
 165         extract_token_addrs(trp, (char*)ESRC(&ehdr), (char*)EDST(&ehdr));
 166
 167         /* Adjust for source routing information in the MAC header */
 168         if (IS_SOURCE_ROUTED(trp)) {
 169                 /* Clear source-routed bit */
 170                 *ESRC(&ehdr) &= 0x7f;
 171
 172                 if (ndo->ndo_eflag)
 173                         token_hdr_print(ndo, trp, length, ESRC(&ehdr), EDST(&ehdr));
 174
 175                 if (caplen < TOKEN_HDRLEN + 2) {
 176                         ND_PRINT((ndo, "%s", tstr));
 177                         return hdr_len;
 178                 }
 179                 route_len = RIF_LENGTH(trp);
 180                 hdr_len += route_len;
 181                 if (caplen < hdr_len) {
 182                         ND_PRINT((ndo, "%s", tstr));
 183                         return hdr_len;
 184                 }
 185                 if (ndo->ndo_vflag) {
 186                         ND_PRINT((ndo, "%s ", broadcast_indicator[BROADCAST(trp)]));
 187                         ND_PRINT((ndo, "%s", direction[DIRECTION(trp)]));
 188
 189                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 190                                 ND_PRINT((ndo, " [%d:%d]", RING_NUMBER(trp, seg),
 191                                     BRIDGE_NUMBER(trp, seg)));
 192                 } else {
 193                         ND_PRINT((ndo, "rt = %x", EXTRACT_16BITS(&trp->token_rcf)));
 194
 195                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 196                                 ND_PRINT((ndo, ":%x", EXTRACT_16BITS(&trp->token_rseg[seg])));
 197                 }
 198                 ND_PRINT((ndo, " (%s) ", largest_frame[LARGEST_FRAME(trp)]));
 199         } else {
 200                 if (ndo->ndo_eflag)
 201                         token_hdr_print(ndo, trp, length, ESRC(&ehdr), EDST(&ehdr));
 202         }
 203
 204         /* Skip over token ring MAC header and routing information */
 205         length -= hdr_len;
 206         p += hdr_len;
 207         caplen -= hdr_len;
 208
 209         /* Frame Control field determines interpretation of packet */
 210         if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
 211                 /* Try to print the LLC-layer header & higher layers */
 212                 llc_hdrlen = llc_print(ndo, p, length, caplen, ESRC(&ehdr),
 213                     EDST(&ehdr));
 214                 if (llc_hdrlen < 0) {
 215                         /* packet type not known, print raw packet */
 216                         if (!ndo->ndo_suppress_default_print)
 217                                 ND_DEFAULTPRINT(p, caplen);
 218                         llc_hdrlen = -llc_hdrlen;
 219                 }
 220                 hdr_len += llc_hdrlen;
 221         } else {
 222                 /* Some kinds of TR packet we cannot handle intelligently */
 223                 /* XXX - dissect MAC packets if frame type is 0 */
 224                 if (!ndo->ndo_eflag)
 225                         token_hdr_print(ndo, trp, length + TOKEN_HDRLEN + route_len,
 226                             ESRC(&ehdr), EDST(&ehdr));
 227                 if (!ndo->ndo_suppress_default_print)
 228                         ND_DEFAULTPRINT(p, caplen);
 229         }
 230         return (hdr_len);
 231 }
 232
 233 /*
 234  * This is the top level routine of the printer.  'p' points
 235  * to the TR header of the packet, 'h->ts' is the timestamp,
 236  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 237  * is the number of bytes actually captured.
 238  */
 239 u_int
 240 token_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
 241 {
 242         return (token_print(ndo, p, h->len, h->caplen));
 243 }