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 /* \summary: Token Ring printer */
  28
  29 #ifdef HAVE_CONFIG_H
  30 #include <config.h>
  31 #endif
  32
  33 #include "netdissect-stdinc.h"
  34
  35 #include <string.h>
  36
  37 #include "netdissect.h"
  38 #include "extract.h"
  39 #include "addrtoname.h"
  40
  41 /*
  42  * Copyright (c) 1998, Larry Lile
  43  * All rights reserved.
  44  *
  45  * Redistribution and use in source and binary forms, with or without
  46  * modification, are permitted provided that the following conditions
  47  * are met:
  48  * 1. Redistributions of source code must retain the above copyright
  49  *    notice unmodified, this list of conditions, and the following
  50  *    disclaimer.
  51  * 2. Redistributions in binary form must reproduce the above copyright
  52  *    notice, this list of conditions and the following disclaimer in the
  53  *    documentation and/or other materials provided with the distribution.
  54  *
  55  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  56  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  57  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  58  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  59  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  60  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  61  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  62  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  63  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  64  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  65  * SUCH DAMAGE.
  66  *
  67  */
  68
  69 #define TOKEN_HDRLEN            14
  70 #define ROUTING_SEGMENT_MAX     16
  71 #define IS_SOURCE_ROUTED(trp)   ((trp)->token_shost[0] & 0x80)
  72 #define FRAME_TYPE(trp)         ((EXTRACT_U_1((trp)->token_fc) & 0xC0) >> 6)
  73 #define TOKEN_FC_LLC            1
  74
  75 #define BROADCAST(trp)          ((EXTRACT_BE_U_2((trp)->token_rcf) & 0xE000) >> 13)
  76 #define RIF_LENGTH(trp)         ((EXTRACT_BE_U_2((trp)->token_rcf) & 0x1f00) >> 8)
  77 #define DIRECTION(trp)          ((EXTRACT_BE_U_2((trp)->token_rcf) & 0x0080) >> 7)
  78 #define LARGEST_FRAME(trp)      ((EXTRACT_BE_U_2((trp)->token_rcf) & 0x0070) >> 4)
  79 #define RING_NUMBER(trp, x)     ((EXTRACT_BE_U_2((trp)->token_rseg[x]) & 0xfff0) >> 4)
  80 #define BRIDGE_NUMBER(trp, x)   ((EXTRACT_BE_U_2((trp)->token_rseg[x]) & 0x000f))
  81 #define SEGMENT_COUNT(trp)      ((int)((RIF_LENGTH(trp) - 2) / 2))
  82
  83 struct token_header {
  84         nd_uint8_t   token_ac;
  85         nd_uint8_t   token_fc;
  86         nd_mac_addr  token_dhost;
  87         nd_mac_addr  token_shost;
  88         nd_uint16_t  token_rcf;
  89         nd_uint16_t  token_rseg[ROUTING_SEGMENT_MAX];
  90 };
  91
  92
  93 /* Extract src, dst addresses */
  94 static void
  95 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
  96 {
  97         memcpy(fdst, (const char *)trp->token_dhost, 6);
  98         memcpy(fsrc, (const char *)trp->token_shost, 6);
  99 }
 100
 101 /*
 102  * Print the TR MAC header
 103  */
 104 static void
 105 token_hdr_print(netdissect_options *ndo,
 106                 const struct token_header *trp, u_int length,
 107                 const u_char *fsrc, const u_char *fdst)
 108 {
 109         const char *srcname, *dstname;
 110
 111         srcname = etheraddr_string(ndo, fsrc);
 112         dstname = etheraddr_string(ndo, fdst);
 113
 114         if (!ndo->ndo_qflag)
 115                 ND_PRINT("%02x %02x ",
 116                        EXTRACT_U_1(trp->token_ac),
 117                        EXTRACT_U_1(trp->token_fc));
 118         ND_PRINT("%s > %s, length %u: ",
 119                srcname, dstname,
 120                length);
 121 }
 122
 123 static const char *broadcast_indicator[] = {
 124         "Non-Broadcast", "Non-Broadcast",
 125         "Non-Broadcast", "Non-Broadcast",
 126         "All-routes",    "All-routes",
 127         "Single-route",  "Single-route"
 128 };
 129
 130 static const char *direction[] = {
 131         "Forward", "Backward"
 132 };
 133
 134 static const char *largest_frame[] = {
 135         "516",
 136         "1500",
 137         "2052",
 138         "4472",
 139         "8144",
 140         "11407",
 141         "17800",
 142         "??"
 143 };
 144
 145 u_int
 146 token_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
 147 {
 148         const struct token_header *trp;
 149         int llc_hdrlen;
 150         nd_mac_addr srcmac, dstmac;
 151         struct lladdr_info src, dst;
 152         u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
 153         int seg;
 154
 155         ndo->ndo_protocol = "token";
 156         trp = (const struct token_header *)p;
 157
 158         if (caplen < TOKEN_HDRLEN) {
 159                 nd_print_trunc(ndo);
 160                 return hdr_len;
 161         }
 162
 163         /*
 164          * Get the TR addresses into a canonical form
 165          */
 166         extract_token_addrs(trp, (char*)srcmac, (char*)dstmac);
 167
 168         /* Adjust for source routing information in the MAC header */
 169         if (IS_SOURCE_ROUTED(trp)) {
 170                 /* Clear source-routed bit */
 171                 srcmac[0] &= 0x7f;
 172
 173                 if (ndo->ndo_eflag)
 174                         token_hdr_print(ndo, trp, length, srcmac, dstmac);
 175
 176                 if (caplen < TOKEN_HDRLEN + 2) {
 177                         nd_print_trunc(ndo);
 178                         return hdr_len;
 179                 }
 180                 route_len = RIF_LENGTH(trp);
 181                 hdr_len += route_len;
 182                 if (caplen < hdr_len) {
 183                         nd_print_trunc(ndo);
 184                         return hdr_len;
 185                 }
 186                 if (ndo->ndo_vflag) {
 187                         ND_PRINT("%s ", broadcast_indicator[BROADCAST(trp)]);
 188                         ND_PRINT("%s", direction[DIRECTION(trp)]);
 189
 190                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 191                                 ND_PRINT(" [%u:%u]", RING_NUMBER(trp, seg),
 192                                     BRIDGE_NUMBER(trp, seg));
 193                 } else {
 194                         ND_PRINT("rt = %x", EXTRACT_BE_U_2(trp->token_rcf));
 195
 196                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 197                                 ND_PRINT(":%x", EXTRACT_BE_U_2(trp->token_rseg[seg]));
 198                 }
 199                 ND_PRINT(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
 200         } else {
 201                 if (ndo->ndo_eflag)
 202                         token_hdr_print(ndo, trp, length, srcmac, dstmac);
 203         }
 204
 205         src.addr = srcmac;
 206         src.addr_string = etheraddr_string;
 207         dst.addr = dstmac;
 208         dst.addr_string = etheraddr_string;
 209
 210         /* Skip over token ring MAC header and routing information */
 211         length -= hdr_len;
 212         p += hdr_len;
 213         caplen -= hdr_len;
 214
 215         /* Frame Control field determines interpretation of packet */
 216         if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
 217                 /* Try to print the LLC-layer header & higher layers */
 218                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 219                 if (llc_hdrlen < 0) {
 220                         /* packet type not known, print raw packet */
 221                         if (!ndo->ndo_suppress_default_print)
 222                                 ND_DEFAULTPRINT(p, caplen);
 223                         llc_hdrlen = -llc_hdrlen;
 224                 }
 225                 hdr_len += llc_hdrlen;
 226         } else {
 227                 /* Some kinds of TR packet we cannot handle intelligently */
 228                 /* XXX - dissect MAC packets if frame type is 0 */
 229                 if (!ndo->ndo_eflag)
 230                         token_hdr_print(ndo, trp, length + TOKEN_HDRLEN + route_len,
 231                             srcmac, dstmac);
 232                 if (!ndo->ndo_suppress_default_print)
 233                         ND_DEFAULTPRINT(p, caplen);
 234         }
 235         return (hdr_len);
 236 }
 237
 238 /*
 239  * This is the top level routine of the printer.  'p' points
 240  * to the TR header of the packet, 'h->ts' is the timestamp,
 241  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 242  * is the number of bytes actually captured.
 243  */
 244 u_int
 245 token_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
 246 {
 247         ndo->ndo_protocol = "token_if";
 248         return (token_print(ndo, p, h->len, h->caplen));
 249 }