external/bsd/tcpdump/dist/print-cdp.c

   1 /*
   2  * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
   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  * Code by Gert Doering, SpaceNet GmbH, gert@space.net
  22  *
  23  * Reference documentation:
  24  *    http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
  25  */
  26
  27 #include <sys/cdefs.h>
  28 #ifndef lint
  29 __RCSID("$NetBSD: print-cdp.c,v 1.6 2015/03/31 21:59:35 christos Exp $");
  30 #endif
  31
  32 #define NETDISSECT_REWORKED
  33 #ifdef HAVE_CONFIG_H
  34 #include "config.h"
  35 #endif
  36
  37 #include <tcpdump-stdinc.h>
  38
  39 #include <string.h>
  40
  41 #include "interface.h"
  42 #include "addrtoname.h"
  43 #include "extract.h"                    /* must come after interface.h */
  44 #include "nlpid.h"
  45
  46 static const char tstr[] = "[|cdp]";
  47
  48 #define CDP_HEADER_LEN             4
  49 #define CDP_HEADER_VERSION_OFFSET  0
  50 #define CDP_HEADER_TTL_OFFSET      1
  51 #define CDP_HEADER_CHECKSUM_OFFSET 2
  52
  53 #define CDP_TLV_HEADER_LEN  4
  54 #define CDP_TLV_TYPE_OFFSET 0
  55 #define CDP_TLV_LEN_OFFSET  2
  56
  57 static const struct tok cdp_tlv_values[] = {
  58     { 0x01,             "Device-ID"},
  59     { 0x02,             "Address"},
  60     { 0x03,             "Port-ID"},
  61     { 0x04,             "Capability"},
  62     { 0x05,             "Version String"},
  63     { 0x06,             "Platform"},
  64     { 0x07,             "Prefixes"},
  65     { 0x08,             "Protocol-Hello option"},
  66     { 0x09,             "VTP Management Domain"},
  67     { 0x0a,             "Native VLAN ID"},
  68     { 0x0b,             "Duplex"},
  69     { 0x0e,             "ATA-186 VoIP VLAN request"},
  70     { 0x0f,             "ATA-186 VoIP VLAN assignment"},
  71     { 0x10,             "power consumption"},
  72     { 0x11,             "MTU"},
  73     { 0x12,             "AVVID trust bitmap"},
  74     { 0x13,             "AVVID untrusted ports CoS"},
  75     { 0x14,             "System Name"},
  76     { 0x15,             "System Object ID (not decoded)"},
  77     { 0x16,             "Management Addresses"},
  78     { 0x17,             "Physical Location"},
  79     { 0, NULL}
  80 };
  81
  82 static const struct tok cdp_capability_values[] = {
  83     { 0x01,             "Router" },
  84     { 0x02,             "Transparent Bridge" },
  85     { 0x04,             "Source Route Bridge" },
  86     { 0x08,             "L2 Switch" },
  87     { 0x10,             "L3 capable" },
  88     { 0x20,             "IGMP snooping" },
  89     { 0x40,             "L1 capable" },
  90     { 0, NULL }
  91 };
  92
  93 static int cdp_print_addr(netdissect_options *, const u_char *, int);
  94 static int cdp_print_prefixes(netdissect_options *, const u_char *, int);
  95 static unsigned long cdp_get_number(const u_char *, int);
  96
  97 void
  98 cdp_print(netdissect_options *ndo,
  99           const u_char *pptr, u_int length, u_int caplen)
 100 {
 101         int type, len, i, j;
 102         const u_char *tptr;
 103
 104         if (caplen < CDP_HEADER_LEN) {
 105                 ND_PRINT((ndo, "%s", tstr));
 106                 return;
 107         }
 108
 109         tptr = pptr; /* temporary pointer */
 110
 111         ND_TCHECK2(*tptr, CDP_HEADER_LEN);
 112         ND_PRINT((ndo, "CDPv%u, ttl: %us", *(tptr + CDP_HEADER_VERSION_OFFSET),
 113                                            *(tptr + CDP_HEADER_TTL_OFFSET)));
 114         if (ndo->ndo_vflag)
 115                 ND_PRINT((ndo, ", checksum: 0x%04x (unverified), length %u", EXTRACT_16BITS(tptr+CDP_HEADER_CHECKSUM_OFFSET), length));
 116         tptr += CDP_HEADER_LEN;
 117
 118         while (tptr < (pptr+length)) {
 119                 ND_TCHECK2(*tptr, CDP_TLV_HEADER_LEN); /* read out Type and Length */
 120                 type = EXTRACT_16BITS(tptr+CDP_TLV_TYPE_OFFSET);
 121                 len  = EXTRACT_16BITS(tptr+CDP_TLV_LEN_OFFSET); /* object length includes the 4 bytes header length */
 122                 if (len < CDP_TLV_HEADER_LEN) {
 123                     if (ndo->ndo_vflag)
 124                         ND_PRINT((ndo, "\n\t%s (0x%02x), TLV length: %u byte%s (too short)",
 125                                tok2str(cdp_tlv_values,"unknown field type", type),
 126                                type,
 127                                len,
 128                                PLURAL_SUFFIX(len))); /* plural */
 129                     else
 130                         ND_PRINT((ndo, ", %s TLV length %u too short",
 131                                tok2str(cdp_tlv_values,"unknown field type", type),
 132                                len));
 133                     break;
 134                 }
 135                 tptr += CDP_TLV_HEADER_LEN;
 136                 len -= CDP_TLV_HEADER_LEN;
 137
 138                 ND_TCHECK2(*tptr, len);
 139
 140                 if (ndo->ndo_vflag || type == 1) { /* in non-verbose mode just print Device-ID */
 141
 142                     if (ndo->ndo_vflag)
 143                         ND_PRINT((ndo, "\n\t%s (0x%02x), value length: %u byte%s: ",
 144                                tok2str(cdp_tlv_values,"unknown field type", type),
 145                                type,
 146                                len,
 147                                PLURAL_SUFFIX(len))); /* plural */
 148
 149                     switch (type) {
 150
 151                     case 0x01: /* Device-ID */
 152                         if (!ndo->ndo_vflag)
 153                             ND_PRINT((ndo, ", Device-ID "));
 154                         ND_PRINT((ndo, "'"));
 155                         (void)fn_printn(ndo, tptr, len, NULL);
 156                         ND_PRINT((ndo, "'"));
 157                         break;
 158                     case 0x02: /* Address */
 159                         if (cdp_print_addr(ndo, tptr, len) < 0)
 160                             goto trunc;
 161                         break;
 162                     case 0x03: /* Port-ID */
 163                         ND_PRINT((ndo, "'"));
 164                         (void)fn_printn(ndo, tptr, len, NULL);
 165                         ND_PRINT((ndo, "'"));
 166                         break;
 167                     case 0x04: /* Capabilities */
 168                         if (len < 4)
 169                             goto trunc;
 170                         ND_PRINT((ndo, "(0x%08x): %s",
 171                                EXTRACT_32BITS(tptr),
 172                                bittok2str(cdp_capability_values, "none", EXTRACT_32BITS(tptr))));
 173                         break;
 174                     case 0x05: /* Version */
 175                         ND_PRINT((ndo, "\n\t  "));
 176                         for (i=0;i<len;i++) {
 177                             j = *(tptr+i);
 178                             ND_PRINT((ndo, "%c", j));
 179                             if (j == 0x0a) /* lets rework the version string to get a nice indentation */
 180                                 ND_PRINT((ndo, "\t  "));
 181                         }
 182                         break;
 183                     case 0x06: /* Platform */
 184                         ND_PRINT((ndo, "'"));
 185                         (void)fn_printn(ndo, tptr, len, NULL);
 186                         ND_PRINT((ndo, "'"));
 187                         break;
 188                     case 0x07: /* Prefixes */
 189                         if (cdp_print_prefixes(ndo, tptr, len) < 0)
 190                             goto trunc;
 191                         break;
 192                     case 0x08: /* Protocol Hello Option - not documented */
 193                         break;
 194                     case 0x09: /* VTP Mgmt Domain  - CDPv2 */
 195                         ND_PRINT((ndo, "'"));
 196                         (void)fn_printn(ndo, tptr, len, NULL);
 197                         ND_PRINT((ndo, "'"));
 198                         break;
 199                     case 0x0a: /* Native VLAN ID - CDPv2 */
 200                         if (len < 2)
 201                             goto trunc;
 202                         ND_PRINT((ndo, "%d", EXTRACT_16BITS(tptr)));
 203                         break;
 204                     case 0x0b: /* Duplex - CDPv2 */
 205                         if (len < 1)
 206                             goto trunc;
 207                         ND_PRINT((ndo, "%s", *(tptr) ? "full": "half"));
 208                         break;
 209
 210                     /* http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cata/186/2_12_m/english/release/notes/186rn21m.html
 211                      * plus more details from other sources
 212                      */
 213                     case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */
 214                         if (len < 3)
 215                             goto trunc;
 216                         ND_PRINT((ndo, "app %d, vlan %d", *(tptr), EXTRACT_16BITS(tptr + 1)));
 217                         break;
 218                     case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
 219                         ND_PRINT((ndo, "%1.2fW", cdp_get_number(tptr, len) / 1000.0));
 220                         break;
 221                     case 0x11: /* MTU - not documented */
 222                         if (len < 4)
 223                             goto trunc;
 224                         ND_PRINT((ndo, "%u bytes", EXTRACT_32BITS(tptr)));
 225                         break;
 226                     case 0x12: /* AVVID trust bitmap - not documented */
 227                         if (len < 1)
 228                             goto trunc;
 229                         ND_PRINT((ndo, "0x%02x", *(tptr)));
 230                         break;
 231                     case 0x13: /* AVVID untrusted port CoS - not documented */
 232                         if (len < 1)
 233                             goto trunc;
 234                         ND_PRINT((ndo, "0x%02x", *(tptr)));
 235                         break;
 236                     case 0x14: /* System Name - not documented */
 237                         ND_PRINT((ndo, "'"));
 238                         (void)fn_printn(ndo, tptr, len, NULL);
 239                         ND_PRINT((ndo, "'"));
 240                         break;
 241                     case 0x16: /* System Object ID - not documented */
 242                         if (cdp_print_addr(ndo, tptr, len) < 0)
 243                                 goto trunc;
 244                         break;
 245                     case 0x17: /* Physical Location - not documented */
 246                         if (len < 1)
 247                             goto trunc;
 248                         ND_PRINT((ndo, "0x%02x", *(tptr)));
 249                         if (len > 1) {
 250                                 ND_PRINT((ndo, "/"));
 251                                 (void)fn_printn(ndo, tptr + 1, len - 1, NULL);
 252                         }
 253                         break;
 254                     default:
 255                         print_unknown_data(ndo, tptr, "\n\t  ", len);
 256                         break;
 257                     }
 258                 }
 259                 tptr = tptr+len;
 260         }
 261         if (ndo->ndo_vflag < 1)
 262             ND_PRINT((ndo, ", length %u", caplen));
 263
 264         return;
 265 trunc:
 266         ND_PRINT((ndo, "%s", tstr));
 267 }
 268
 269 /*
 270  * Protocol type values.
 271  *
 272  * PT_NLPID means that the protocol type field contains an OSI NLPID.
 273  *
 274  * PT_IEEE_802_2 means that the protocol type field contains an IEEE 802.2
 275  * LLC header that specifies that the payload is for that protocol.
 276  */
 277 #define PT_NLPID                1       /* OSI NLPID */
 278 #define PT_IEEE_802_2           2       /* IEEE 802.2 LLC header */
 279
 280 static int
 281 cdp_print_addr(netdissect_options *ndo,
 282                const u_char * p, int l)
 283 {
 284         int pt, pl, al, num;
 285         const u_char *endp = p + l;
 286 #ifdef INET6
 287         static const u_char prot_ipv6[] = {
 288                 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd
 289         };
 290 #endif
 291
 292         ND_TCHECK2(*p, 4);
 293         if (p + 4 > endp)
 294                 goto trunc;
 295         num = EXTRACT_32BITS(p);
 296         p += 4;
 297
 298         while (p < endp && num >= 0) {
 299                 ND_TCHECK2(*p, 2);
 300                 if (p + 2 > endp)
 301                         goto trunc;
 302                 pt = p[0];              /* type of "protocol" field */
 303                 pl = p[1];              /* length of "protocol" field */
 304                 p += 2;
 305
 306                 ND_TCHECK2(p[pl], 2);
 307                 if (p + pl + 2 > endp)
 308                         goto trunc;
 309                 al = EXTRACT_16BITS(&p[pl]);    /* address length */
 310
 311                 if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) {
 312                         /*
 313                          * IPv4: protocol type = NLPID, protocol length = 1
 314                          * (1-byte NLPID), protocol = 0xcc (NLPID for IPv4),
 315                          * address length = 4
 316                          */
 317                         p += 3;
 318
 319                         ND_TCHECK2(*p, 4);
 320                         if (p + 4 > endp)
 321                                 goto trunc;
 322                         ND_PRINT((ndo, "IPv4 (%u) %s", num, ipaddr_string(ndo, p)));
 323                         p += 4;
 324                 }
 325 #ifdef INET6
 326                 else if (pt == PT_IEEE_802_2 && pl == 8 &&
 327                     memcmp(p, prot_ipv6, 8) == 0 && al == 16) {
 328                         /*
 329                          * IPv6: protocol type = IEEE 802.2 header,
 330                          * protocol length = 8 (size of LLC+SNAP header),
 331                          * protocol = LLC+SNAP header with the IPv6
 332                          * Ethertype, address length = 16
 333                          */
 334                         p += 10;
 335                         ND_TCHECK2(*p, al);
 336                         if (p + al > endp)
 337                                 goto trunc;
 338
 339                         ND_PRINT((ndo, "IPv6 (%u) %s", num, ip6addr_string(ndo, p)));
 340                         p += al;
 341                 }
 342 #endif
 343                 else {
 344                         /*
 345                          * Generic case: just print raw data
 346                          */
 347                         ND_TCHECK2(*p, pl);
 348                         if (p + pl > endp)
 349                                 goto trunc;
 350                         ND_PRINT((ndo, "pt=0x%02x, pl=%d, pb=", *(p - 2), pl));
 351                         while (pl-- > 0)
 352                                 ND_PRINT((ndo, " %02x", *p++));
 353                         ND_TCHECK2(*p, 2);
 354                         if (p + 2 > endp)
 355                                 goto trunc;
 356                         al = (*p << 8) + *(p + 1);
 357                         ND_PRINT((ndo, ", al=%d, a=", al));
 358                         p += 2;
 359                         ND_TCHECK2(*p, al);
 360                         if (p + al > endp)
 361                                 goto trunc;
 362                         while (al-- > 0)
 363                                 ND_PRINT((ndo, " %02x", *p++));
 364                 }
 365                 num--;
 366                 if (num)
 367                         ND_PRINT((ndo, " "));
 368         }
 369
 370         return 0;
 371
 372 trunc:
 373         return -1;
 374 }
 375
 376
 377 static int
 378 cdp_print_prefixes(netdissect_options *ndo,
 379                    const u_char * p, int l)
 380 {
 381         if (l % 5)
 382                 goto trunc;
 383
 384         ND_PRINT((ndo, " IPv4 Prefixes (%d):", l / 5));
 385
 386         while (l > 0) {
 387                 ND_PRINT((ndo, " %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]));
 388                 l -= 5;
 389                 p += 5;
 390         }
 391
 392         return 0;
 393
 394 trunc:
 395         return -1;
 396 }
 397
 398 /* read in a <n>-byte number, MSB first
 399  * (of course this can handle max sizeof(long))
 400  */
 401 static unsigned long cdp_get_number(const u_char * p, int l)
 402 {
 403     unsigned long res=0;
 404     while( l>0 )
 405     {
 406         res = (res<<8) + *p;
 407         p++; l--;
 408     }
 409     return res;
 410 }