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 #include <config.h>
  30
  31 #include "netdissect-stdinc.h"
  32
  33 #include <string.h>
  34
  35 #include "netdissect.h"
  36 #include "extract.h"
  37 #include "addrtoname.h"
  38
  39 /*
  40  * Copyright (c) 1998, Larry Lile
  41  * All rights reserved.
  42  *
  43  * Redistribution and use in source and binary forms, with or without
  44  * modification, are permitted provided that the following conditions
  45  * are met:
  46  * 1. Redistributions of source code must retain the above copyright
  47  *    notice unmodified, this list of conditions, and the following
  48  *    disclaimer.
  49  * 2. Redistributions in binary form must reproduce the above copyright
  50  *    notice, this list of conditions and the following disclaimer in the
  51  *    documentation and/or other materials provided with the distribution.
  52  *
  53  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  63  * SUCH DAMAGE.
  64  *
  65  */
  66
  67 #define TOKEN_HDRLEN            14
  68 #define ROUTING_SEGMENT_MAX     16
  69 #define IS_SOURCE_ROUTED(trp)   ((trp)->token_shost[0] & 0x80)
  70 #define FRAME_TYPE(trp)         ((GET_U_1((trp)->token_fc) & 0xC0) >> 6)
  71 #define TOKEN_FC_LLC            1
  72
  73 #define BROADCAST(trp)          ((GET_BE_U_2((trp)->token_rcf) & 0xE000) >> 13)
  74 #define RIF_LENGTH(trp)         ((GET_BE_U_2((trp)->token_rcf) & 0x1f00) >> 8)
  75 #define DIRECTION(trp)          ((GET_BE_U_2((trp)->token_rcf) & 0x0080) >> 7)
  76 #define LARGEST_FRAME(trp)      ((GET_BE_U_2((trp)->token_rcf) & 0x0070) >> 4)
  77 #define RING_NUMBER(trp, x)     ((GET_BE_U_2((trp)->token_rseg[x]) & 0xfff0) >> 4)
  78 #define BRIDGE_NUMBER(trp, x)   (GET_BE_U_2((trp)->token_rseg[x]) & 0x000f)
  79 #define SEGMENT_COUNT(trp)      ((int)((RIF_LENGTH(trp) - 2) / 2))
  80
  81 struct token_header {
  82         nd_uint8_t   token_ac;
  83         nd_uint8_t   token_fc;
  84         nd_mac48  token_dhost;
  85         nd_mac48  token_shost;
  86         nd_uint16_t  token_rcf;
  87         nd_uint16_t  token_rseg[ROUTING_SEGMENT_MAX];
  88 };
  89
  90
  91 /* Extract src, dst addresses */
  92 static void
  93 extract_token_addrs(const struct token_header *trp, char *fsrc, char *fdst)
  94 {
  95         memcpy(fdst, (const char *)trp->token_dhost, 6);
  96         memcpy(fsrc, (const char *)trp->token_shost, 6);
  97 }
  98
  99 /*
 100  * Print the TR MAC header
 101  */
 102 static void
 103 token_hdr_print(netdissect_options *ndo,
 104                 const struct token_header *trp, u_int length,
 105                 const u_char *fsrc, const u_char *fdst)
 106 {
 107         const char *srcname, *dstname;
 108
 109         srcname = mac48_string(ndo, fsrc);
 110         dstname = mac48_string(ndo, fdst);
 111
 112         if (!ndo->ndo_qflag)
 113                 ND_PRINT("%02x %02x ",
 114                        GET_U_1(trp->token_ac),
 115                        GET_U_1(trp->token_fc));
 116         ND_PRINT("%s > %s, length %u: ",
 117                srcname, dstname,
 118                length);
 119 }
 120
 121 static const char *broadcast_indicator[] = {
 122         "Non-Broadcast", "Non-Broadcast",
 123         "Non-Broadcast", "Non-Broadcast",
 124         "All-routes",    "All-routes",
 125         "Single-route",  "Single-route"
 126 };
 127
 128 static const char *direction[] = {
 129         "Forward", "Backward"
 130 };
 131
 132 static const char *largest_frame[] = {
 133         "516",
 134         "1500",
 135         "2052",
 136         "4472",
 137         "8144",
 138         "11407",
 139         "17800",
 140         "??"
 141 };
 142
 143 u_int
 144 token_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
 145 {
 146         const struct token_header *trp;
 147         int llc_hdrlen;
 148         nd_mac48 srcmac, dstmac;
 149         struct lladdr_info src, dst;
 150         u_int route_len = 0, hdr_len = TOKEN_HDRLEN;
 151         int seg;
 152
 153         ndo->ndo_protocol = "token-ring";
 154         trp = (const struct token_header *)p;
 155
 156         if (caplen < TOKEN_HDRLEN) {
 157                 nd_print_trunc(ndo);
 158                 return hdr_len;
 159         }
 160
 161         /*
 162          * Get the TR addresses into a canonical form
 163          */
 164         extract_token_addrs(trp, (char*)srcmac, (char*)dstmac);
 165
 166         /* Adjust for source routing information in the MAC header */
 167         if (IS_SOURCE_ROUTED(trp)) {
 168                 /* Clear source-routed bit */
 169                 srcmac[0] &= 0x7f;
 170
 171                 if (ndo->ndo_eflag)
 172                         token_hdr_print(ndo, trp, length, srcmac, dstmac);
 173
 174                 if (caplen < TOKEN_HDRLEN + 2) {
 175                         nd_print_trunc(ndo);
 176                         return hdr_len;
 177                 }
 178                 route_len = RIF_LENGTH(trp);
 179                 hdr_len += route_len;
 180                 if (caplen < hdr_len) {
 181                         nd_print_trunc(ndo);
 182                         return hdr_len;
 183                 }
 184                 if (ndo->ndo_vflag) {
 185                         ND_PRINT("%s ", broadcast_indicator[BROADCAST(trp)]);
 186                         ND_PRINT("%s", direction[DIRECTION(trp)]);
 187
 188                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 189                                 ND_PRINT(" [%u:%u]", RING_NUMBER(trp, seg),
 190                                     BRIDGE_NUMBER(trp, seg));
 191                 } else {
 192                         ND_PRINT("rt = %x", GET_BE_U_2(trp->token_rcf));
 193
 194                         for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
 195                                 ND_PRINT(":%x",
 196                                          GET_BE_U_2(trp->token_rseg[seg]));
 197                 }
 198                 ND_PRINT(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
 199         } else {
 200                 if (ndo->ndo_eflag)
 201                         token_hdr_print(ndo, trp, length, srcmac, dstmac);
 202         }
 203
 204         src.addr = srcmac;
 205         src.addr_string = mac48_string;
 206         dst.addr = dstmac;
 207         dst.addr_string = mac48_string;
 208
 209         /* Skip over token ring MAC header and routing information */
 210         length -= hdr_len;
 211         p += hdr_len;
 212         caplen -= hdr_len;
 213
 214         /* Frame Control field determines interpretation of packet */
 215         if (FRAME_TYPE(trp) == TOKEN_FC_LLC) {
 216                 /* Try to print the LLC-layer header & higher layers */
 217                 llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 218                 if (llc_hdrlen < 0) {
 219                         /* packet type not known, print raw packet */
 220                         if (!ndo->ndo_suppress_default_print)
 221                                 ND_DEFAULTPRINT(p, caplen);
 222                         llc_hdrlen = -llc_hdrlen;
 223                 }
 224                 hdr_len += llc_hdrlen;
 225         } else {
 226                 /* Some kinds of TR packet we cannot handle intelligently */
 227                 /* XXX - dissect MAC packets if frame type is 0 */
 228                 if (!ndo->ndo_eflag)
 229                         token_hdr_print(ndo, trp, length + TOKEN_HDRLEN + route_len,
 230                             srcmac, dstmac);
 231                 if (!ndo->ndo_suppress_default_print)
 232                         ND_DEFAULTPRINT(p, caplen);
 233         }
 234         return (hdr_len);
 235 }
 236
 237 /*
 238  * This is the top level routine of the printer.  'p' points
 239  * to the TR header of the packet, 'h->ts' is the timestamp,
 240  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 241  * is the number of bytes actually captured.
 242  */
 243 void
 244 token_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
 245 {
 246         ndo->ndo_protocol = "token-ring";
 247         ndo->ndo_ll_hdr_len += token_print(ndo, p, h->len, h->caplen);
 248 }