contrib/tcpdump/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 #ifndef lint
  28 static const char rcsid[] _U_ =
  29     "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.25 2004-10-07 14:53:11 hannes Exp $";
  30 #endif
  31
  32 #ifdef HAVE_CONFIG_H
  33 #include "config.h"
  34 #endif
  35
  36 #include <tcpdump-stdinc.h>
  37
  38 #include <stdio.h>
  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 #define CDP_HEADER_LEN  4
  47
  48 static struct tok cdp_tlv_values[] = {
  49     { 0x01,             "Device-ID"},
  50     { 0x02,             "Address"},
  51     { 0x03,             "Port-ID"},
  52     { 0x04,             "Capability"},
  53     { 0x05,             "Version String"},
  54     { 0x06,             "Platform"},
  55     { 0x07,             "Prefixes"},
  56     { 0x08,             "Protocol-Hello option"},
  57     { 0x09,             "VTP Management Domain"},
  58     { 0x0a,             "Native VLAN ID"},
  59     { 0x0b,             "Duplex"},
  60     { 0x0e,             "ATA-186 VoIP VLAN request"},
  61     { 0x0f,             "ATA-186 VoIP VLAN assignment"},
  62     { 0x10,             "power consumption"},
  63     { 0x11,             "MTU"},
  64     { 0x12,             "AVVID trust bitmap"},
  65     { 0x13,             "AVVID untrusted ports CoS"},
  66     { 0x14,             "System Name"},
  67     { 0x15,             "System Object ID (not decoded)"},
  68     { 0x16,             "Management Addresses"},
  69     { 0x17,             "Physical Location"},
  70     { 0, NULL}
  71 };
  72
  73 static struct tok cdp_capability_values[] = {
  74     { 0x01,             "Router" },
  75     { 0x02,             "Transparent Bridge" },
  76     { 0x04,             "Source Route Bridge" },
  77     { 0x08,             "L2 Switch" },
  78     { 0x10,             "L3 capable" },
  79     { 0x20,             "IGMP snooping" },
  80     { 0x40,             "L1 capable" },
  81     { 0, NULL }
  82 };
  83
  84 static int cdp_print_addr(const u_char *, int);
  85 static int cdp_print_prefixes(const u_char *, int);
  86 static unsigned long cdp_get_number(const u_char *, int);
  87
  88 void
  89 cdp_print(const u_char *pptr, u_int length, u_int caplen)
  90 {
  91         int type, len, i, j;
  92         const u_char *tptr;
  93
  94         if (caplen < CDP_HEADER_LEN) {
  95                 (void)printf("[|cdp]");
  96                 return;
  97         }
  98
  99         tptr = pptr; /* temporary pointer */
 100
 101         if (!TTEST2(*tptr, CDP_HEADER_LEN))
 102                 goto trunc;
 103         printf("CDPv%u, ttl: %us", *tptr, *(tptr+1));
 104         if (vflag)
 105                 printf(", checksum: %u (unverified), length %u", EXTRACT_16BITS(tptr), length);
 106         tptr += CDP_HEADER_LEN;
 107
 108         while (tptr < (pptr+length)) {
 109
 110                 if (!TTEST2(*tptr, 4)) /* read out Type and Length */
 111                     goto trunc;
 112                 type = EXTRACT_16BITS(tptr);
 113                 len  = EXTRACT_16BITS(tptr+2); /* object length includes the 4 bytes header length */
 114                 tptr += 4;
 115                 len -= 4;
 116
 117                 if (!TTEST2(*tptr, len))
 118                         goto trunc;
 119
 120                 if (vflag || type == 1) { /* in non-verbose mode just print Device-ID */
 121
 122                     if (vflag)
 123                         printf("\n\t%s (0x%02x), length: %u byte%s: ",
 124                                tok2str(cdp_tlv_values,"unknown field type", type),
 125                                type,
 126                                len,
 127                                len>1 ? "s" : ""); /* plural */
 128
 129                     switch (type) {
 130
 131                     case 0x01: /* Device-ID */
 132                         if (!vflag)
 133                             printf(", Device-ID '%.*s'", len, tptr);
 134                         else
 135                             printf("'%.*s'", len, tptr);
 136                         break;
 137                     case 0x02: /* Address */
 138                         if (cdp_print_addr(tptr, len) < 0)
 139                             goto trunc;
 140                         break;
 141                     case 0x03: /* Port-ID */
 142                         printf("'%.*s'", len, tptr);
 143                         break;
 144                     case 0x04: /* Capabilities */
 145                         printf("(0x%08x): %s",
 146                                EXTRACT_32BITS(tptr),
 147                                bittok2str(cdp_capability_values, "none",EXTRACT_32BITS(tptr)));
 148                         break;
 149                     case 0x05: /* Version */
 150                         printf("\n\t  ");
 151                         for (i=0;i<len;i++) {
 152                             j = *(tptr+i);
 153                             putchar(j);
 154                             if (j == 0x0a) /* lets rework the version string to get a nice identation */
 155                                 printf("\t  ");
 156                         }
 157                         break;
 158                     case 0x06: /* Platform */
 159                         printf("'%.*s'", len, tptr);
 160                         break;
 161                     case 0x07: /* Prefixes */
 162                         if (cdp_print_prefixes(tptr, len) < 0)
 163                             goto trunc;
 164                         break;
 165                     case 0x08: /* Protocol Hello Option - not documented */
 166                         break;
 167                     case 0x09: /* VTP Mgmt Domain  - not documented */
 168                         printf("'%.*s'", len,tptr);
 169                         break;
 170                     case 0x0a: /* Native VLAN ID - not documented */
 171                         printf("%d",EXTRACT_16BITS(tptr));
 172                         break;
 173                     case 0x0b: /* Duplex - not documented */
 174                         printf("%s", *(tptr) ? "full": "half");
 175                         break;
 176
 177                     /* http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm
 178                      * plus more details from other sources
 179                      */
 180                     case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */
 181                         printf("app %d, vlan %d",
 182                                *(tptr), EXTRACT_16BITS(tptr+1));
 183                         break;
 184                     case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
 185                         printf("%1.2fW",
 186                                cdp_get_number(tptr, len)/1000.0 );
 187                         break;
 188                     case 0x11: /* MTU - not documented */
 189                         printf("%u bytes", EXTRACT_32BITS(tptr));
 190                         break;
 191                     case 0x12: /* AVVID trust bitmap - not documented */
 192                         printf("0x%02x", *(tptr) );
 193                         break;
 194                     case 0x13: /* AVVID untrusted port CoS - not documented */
 195                         printf("0x%02x", *(tptr));
 196                         break;
 197                     case 0x14: /* System Name - not documented */
 198                         printf("'%.*s'", len, tptr);
 199                         break;
 200                     case 0x16: /* System Object ID - not documented */
 201                         if (cdp_print_addr(tptr, len) < 0)
 202                                 goto trunc;
 203                         break;
 204                     case 0x17: /* Physical Location - not documented */
 205                         printf("0x%02x/%.*s", *(tptr), len - 1, tptr + 1 );
 206                         break;
 207                     default:
 208                         print_unknown_data(tptr,"\n\t  ",len);
 209                         break;
 210                     }
 211                 }
 212                 /* avoid infinite loop */
 213                 if (len == 0)
 214                         break;
 215                 tptr = tptr+len;
 216         }
 217         if (vflag < 1)
 218             printf(", length %u",caplen);
 219
 220         return;
 221 trunc:
 222         printf("[|cdp]");
 223 }
 224
 225 /*
 226  * Protocol type values.
 227  *
 228  * PT_NLPID means that the protocol type field contains an OSI NLPID.
 229  *
 230  * PT_IEEE_802_2 means that the protocol type field contains an IEEE 802.2
 231  * LLC header that specifies that the payload is for that protocol.
 232  */
 233 #define PT_NLPID                1       /* OSI NLPID */
 234 #define PT_IEEE_802_2           2       /* IEEE 802.2 LLC header */
 235
 236 static int
 237 cdp_print_addr(const u_char * p, int l)
 238 {
 239         int pt, pl, al, num;
 240         const u_char *endp = p + l;
 241 #ifdef INET6
 242         static u_char prot_ipv6[] = {
 243                 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd
 244         };
 245 #endif
 246
 247         TCHECK2(*p, 2);
 248         num = EXTRACT_32BITS(p);
 249         p += 4;
 250
 251         while (p < endp && num >= 0) {
 252                 TCHECK2(*p, 2);
 253                 if (p + 2 > endp)
 254                         goto trunc;
 255                 pt = p[0];              /* type of "protocol" field */
 256                 pl = p[1];              /* length of "protocol" field */
 257                 p += 2;
 258
 259                 TCHECK2(p[pl], 2);
 260                 if (p + pl + 2 > endp)
 261                         goto trunc;
 262                 al = EXTRACT_16BITS(&p[pl]);    /* address length */
 263
 264                 if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) {
 265                         /*
 266                          * IPv4: protocol type = NLPID, protocol length = 1
 267                          * (1-byte NLPID), protocol = 0xcc (NLPID for IPv4),
 268                          * address length = 4
 269                          */
 270                         p += 3;
 271
 272                         TCHECK2(*p, 4);
 273                         if (p + 4 > endp)
 274                                 goto trunc;
 275                         printf("IPv4 (%u) %s",
 276                                num,
 277                                ipaddr_string(p));
 278                         p += 4;
 279                 }
 280 #ifdef INET6
 281                 else if (pt == PT_IEEE_802_2 && pl == 8 &&
 282                     memcmp(p, prot_ipv6, 8) == 0 && al == 16) {
 283                         /*
 284                          * IPv6: protocol type = IEEE 802.2 header,
 285                          * protocol length = 8 (size of LLC+SNAP header),
 286                          * protocol = LLC+SNAP header with the IPv6
 287                          * Ethertype, address length = 16
 288                          */
 289                         p += 10;
 290                         TCHECK2(*p, al);
 291                         if (p + al > endp)
 292                                 goto trunc;
 293
 294                         printf("IPv6 (%u) %s",
 295                                num,
 296                                ip6addr_string(p));
 297                         p += al;
 298                 }
 299 #endif
 300                 else {
 301                         /*
 302                          * Generic case: just print raw data
 303                          */
 304                         TCHECK2(*p, pl);
 305                         if (p + pl > endp)
 306                                 goto trunc;
 307                         printf("pt=0x%02x, pl=%d, pb=", *(p - 2), pl);
 308                         while (pl-- > 0)
 309                                 printf(" %02x", *p++);
 310                         TCHECK2(*p, 2);
 311                         if (p + 2 > endp)
 312                                 goto trunc;
 313                         al = (*p << 8) + *(p + 1);
 314                         printf(", al=%d, a=", al);
 315                         p += 2;
 316                         TCHECK2(*p, al);
 317                         if (p + al > endp)
 318                                 goto trunc;
 319                         while (al-- > 0)
 320                                 printf(" %02x", *p++);
 321                 }
 322                 num--;
 323                 if (num)
 324                         printf(" ");
 325         }
 326
 327         return 0;
 328
 329 trunc:
 330         return -1;
 331 }
 332
 333
 334 static int
 335 cdp_print_prefixes(const u_char * p, int l)
 336 {
 337         if (l % 5)
 338                 goto trunc;
 339
 340         printf(" IPv4 Prefixes (%d):", l / 5);
 341
 342         while (l > 0) {
 343                 printf(" %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]);
 344                 l -= 5;
 345                 p += 5;
 346         }
 347
 348         return 0;
 349
 350 trunc:
 351         return -1;
 352 }
 353
 354 /* read in a <n>-byte number, MSB first
 355  * (of course this can handle max sizeof(long))
 356  */
 357 static unsigned long cdp_get_number(const u_char * p, int l)
 358 {
 359     unsigned long res=0;
 360     while( l>0 )
 361     {
 362         res = (res<<8) + *p;
 363         p++; l--;
 364     }
 365     return res;
 366 }