dist/tcpdump/print-cdp.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that: (1) source code distributions
   9  * retain the above copyright notice and this paragraph in its entirety, (2)
  10  * distributions including binary code include the above copyright notice and
  11  * this paragraph in its entirety in the documentation or other materials
  12  * provided with the distribution, and (3) all advertising materials mentioning
  13  * features or use of this software display the following acknowledgement:
  14  * ``This product includes software developed by the University of California,
  15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  16  * the University nor the names of its contributors may be used to endorse
  17  * or promote products derived from this software without specific prior
  18  * written permission.
  19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  22  *
  23  * Code by Gert Doering, SpaceNet GmbH, gert@space.net
  24  *
  25  * Reference documentation:
  26  *    http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
  27  */
  28
  29 #include <sys/cdefs.h>
  30 #ifndef lint
  31 #if 0
  32 static const char rcsid[] _U_ =
  33     "@(#) Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.25 2004/10/07 14:53:11 hannes Exp";
  34 #else
  35 __RCSID("$NetBSD: tcpdump2rcsid.ex,v 1.1 2001/06/25 20:09:58 itojun Exp $");
  36 #endif
  37 #endif
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include "config.h"
  41 #endif
  42
  43 #include <tcpdump-stdinc.h>
  44
  45 #include <stdio.h>
  46 #include <string.h>
  47
  48 #include "interface.h"
  49 #include "addrtoname.h"
  50 #include "extract.h"                    /* must come after interface.h */
  51 #include "nlpid.h"
  52
  53 #define CDP_HEADER_LEN  4
  54
  55 static struct tok cdp_tlv_values[] = {
  56     { 0x01,             "Device-ID"},
  57     { 0x02,             "Address"},
  58     { 0x03,             "Port-ID"},
  59     { 0x04,             "Capability"},
  60     { 0x05,             "Version String"},
  61     { 0x06,             "Platform"},
  62     { 0x07,             "Prefixes"},
  63     { 0x08,             "Protocol-Hello option"},
  64     { 0x09,             "VTP Management Domain"},
  65     { 0x0a,             "Native VLAN ID"},
  66     { 0x0b,             "Duplex"},
  67     { 0x0e,             "ATA-186 VoIP VLAN request"},
  68     { 0x0f,             "ATA-186 VoIP VLAN assignment"},
  69     { 0x10,             "power consumption"},
  70     { 0x11,             "MTU"},
  71     { 0x12,             "AVVID trust bitmap"},
  72     { 0x13,             "AVVID untrusted ports CoS"},
  73     { 0x14,             "System Name"},
  74     { 0x15,             "System Object ID (not decoded)"},
  75     { 0x16,             "Management Addresses"},
  76     { 0x17,             "Physical Location"},
  77     { 0, NULL}
  78 };
  79
  80 static struct tok cdp_capability_values[] = {
  81     { 0x01,             "Router" },
  82     { 0x02,             "Transparent Bridge" },
  83     { 0x04,             "Source Route Bridge" },
  84     { 0x08,             "L2 Switch" },
  85     { 0x10,             "L3 capable" },
  86     { 0x20,             "IGMP snooping" },
  87     { 0x40,             "L1 capable" },
  88     { 0, NULL }
  89 };
  90
  91 static int cdp_print_addr(const u_char *, int);
  92 static int cdp_print_prefixes(const u_char *, int);
  93 static unsigned long cdp_get_number(const u_char *, int);
  94
  95 void
  96 cdp_print(const u_char *pptr, u_int length, u_int caplen)
  97 {
  98         int type, len, i, j;
  99         const u_char *tptr;
 100
 101         if (caplen < CDP_HEADER_LEN) {
 102                 (void)printf("[|cdp]");
 103                 return;
 104         }
 105
 106         tptr = pptr; /* temporary pointer */
 107
 108         if (!TTEST2(*tptr, CDP_HEADER_LEN))
 109                 goto trunc;
 110         printf("CDPv%u, ttl: %us", *tptr, *(tptr+1));
 111         if (vflag)
 112                 printf(", checksum: %u (unverified), length %u", EXTRACT_16BITS(tptr), length);
 113         tptr += CDP_HEADER_LEN;
 114
 115         while (tptr < (pptr+length)) {
 116
 117                 if (!TTEST2(*tptr, 4)) /* read out Type and Length */
 118                     goto trunc;
 119                 type = EXTRACT_16BITS(tptr);
 120                 len  = EXTRACT_16BITS(tptr+2); /* object length includes the 4 bytes header length */
 121                 tptr += 4;
 122                 len -= 4;
 123
 124                 if (!TTEST2(*tptr, len))
 125                         goto trunc;
 126
 127                 if (vflag || type == 1) { /* in non-verbose mode just print Device-ID */
 128
 129                     if (vflag)
 130                         printf("\n\t%s (0x%02x), length: %u byte%s: ",
 131                                tok2str(cdp_tlv_values,"unknown field type", type),
 132                                type,
 133                                len,
 134                                len>1 ? "s" : ""); /* plural */
 135
 136                     switch (type) {
 137
 138                     case 0x01: /* Device-ID */
 139                         if (!vflag)
 140                             printf(", Device-ID '%.*s'", len, tptr);
 141                         else
 142                             printf("'%.*s'", len, tptr);
 143                         break;
 144                     case 0x02: /* Address */
 145                         if (cdp_print_addr(tptr, len) < 0)
 146                             goto trunc;
 147                         break;
 148                     case 0x03: /* Port-ID */
 149                         printf("'%.*s'", len, tptr);
 150                         break;
 151                     case 0x04: /* Capabilities */
 152                         printf("(0x%08x): %s",
 153                                EXTRACT_32BITS(tptr),
 154                                bittok2str(cdp_capability_values, "none",EXTRACT_32BITS(tptr)));
 155                         break;
 156                     case 0x05: /* Version */
 157                         printf("\n\t  ");
 158                         for (i=0;i<len;i++) {
 159                             j = *(tptr+i);
 160                             putchar(j);
 161                             if (j == 0x0a) /* lets rework the version string to get a nice identation */
 162                                 printf("\t  ");
 163                         }
 164                         break;
 165                     case 0x06: /* Platform */
 166                         printf("'%.*s'", len, tptr);
 167                         break;
 168                     case 0x07: /* Prefixes */
 169                         if (cdp_print_prefixes(tptr, len) < 0)
 170                             goto trunc;
 171                         break;
 172                     case 0x08: /* Protocol Hello Option - not documented */
 173                         break;
 174                     case 0x09: /* VTP Mgmt Domain  - not documented */
 175                         printf("'%.*s'", len,tptr);
 176                         break;
 177                     case 0x0a: /* Native VLAN ID - not documented */
 178                         printf("%d",EXTRACT_16BITS(tptr));
 179                         break;
 180                     case 0x0b: /* Duplex - not documented */
 181                         printf("%s", *(tptr) ? "full": "half");
 182                         break;
 183
 184                     /* http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm
 185                      * plus more details from other sources
 186                      */
 187                     case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */
 188                         printf("app %d, vlan %d",
 189                                *(tptr), EXTRACT_16BITS(tptr+1));
 190                         break;
 191                     case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
 192                         printf("%1.2fW",
 193                                cdp_get_number(tptr, len)/1000.0 );
 194                         break;
 195                     case 0x11: /* MTU - not documented */
 196                         printf("%u bytes", EXTRACT_32BITS(tptr));
 197                         break;
 198                     case 0x12: /* AVVID trust bitmap - not documented */
 199                         printf("0x%02x", *(tptr) );
 200                         break;
 201                     case 0x13: /* AVVID untrusted port CoS - not documented */
 202                         printf("0x%02x", *(tptr));
 203                         break;
 204                     case 0x14: /* System Name - not documented */
 205                         printf("'%.*s'", len, tptr);
 206                         break;
 207                     case 0x16: /* System Object ID - not documented */
 208                         if (cdp_print_addr(tptr, len) < 0)
 209                                 goto trunc;
 210                         break;
 211                     case 0x17: /* Physical Location - not documented */
 212                         printf("0x%02x/%.*s", *(tptr), len - 1, tptr + 1 );
 213                         break;
 214                     default:
 215                         print_unknown_data(tptr,"\n\t  ",len);
 216                         break;
 217                     }
 218                 }
 219                 /* avoid infinite loop */
 220                 if (len == 0)
 221                         break;
 222                 tptr = tptr+len;
 223         }
 224         if (vflag < 1)
 225             printf(", length %u",caplen);
 226
 227         return;
 228 trunc:
 229         printf("[|cdp]");
 230 }
 231
 232 /*
 233  * Protocol type values.
 234  *
 235  * PT_NLPID means that the protocol type field contains an OSI NLPID.
 236  *
 237  * PT_IEEE_802_2 means that the protocol type field contains an IEEE 802.2
 238  * LLC header that specifies that the payload is for that protocol.
 239  */
 240 #define PT_NLPID                1       /* OSI NLPID */
 241 #define PT_IEEE_802_2           2       /* IEEE 802.2 LLC header */
 242
 243 static int
 244 cdp_print_addr(const u_char * p, int l)
 245 {
 246         int pt, pl, al, num;
 247         const u_char *endp = p + l;
 248 #ifdef INET6
 249         static u_char prot_ipv6[] = {
 250                 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd
 251         };
 252 #endif
 253
 254         TCHECK2(*p, 2);
 255         num = EXTRACT_32BITS(p);
 256         p += 4;
 257
 258         while (p < endp && num >= 0) {
 259                 TCHECK2(*p, 2);
 260                 if (p + 2 > endp)
 261                         goto trunc;
 262                 pt = p[0];              /* type of "protocol" field */
 263                 pl = p[1];              /* length of "protocol" field */
 264                 p += 2;
 265
 266                 TCHECK2(p[pl], 2);
 267                 if (p + pl + 2 > endp)
 268                         goto trunc;
 269                 al = EXTRACT_16BITS(&p[pl]);    /* address length */
 270
 271                 if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) {
 272                         /*
 273                          * IPv4: protocol type = NLPID, protocol length = 1
 274                          * (1-byte NLPID), protocol = 0xcc (NLPID for IPv4),
 275                          * address length = 4
 276                          */
 277                         p += 3;
 278
 279                         TCHECK2(*p, 4);
 280                         if (p + 4 > endp)
 281                                 goto trunc;
 282                         printf("IPv4 (%u) %s",
 283                                num,
 284                                ipaddr_string(p));
 285                         p += 4;
 286                 }
 287 #ifdef INET6
 288                 else if (pt == PT_IEEE_802_2 && pl == 8 &&
 289                     memcmp(p, prot_ipv6, 8) == 0 && al == 16) {
 290                         /*
 291                          * IPv6: protocol type = IEEE 802.2 header,
 292                          * protocol length = 8 (size of LLC+SNAP header),
 293                          * protocol = LLC+SNAP header with the IPv6
 294                          * Ethertype, address length = 16
 295                          */
 296                         p += 10;
 297                         TCHECK2(*p, al);
 298                         if (p + al > endp)
 299                                 goto trunc;
 300
 301                         printf("IPv6 (%u) %s",
 302                                num,
 303                                ip6addr_string(p));
 304                         p += al;
 305                 }
 306 #endif
 307                 else {
 308                         /*
 309                          * Generic case: just print raw data
 310                          */
 311                         TCHECK2(*p, pl);
 312                         if (p + pl > endp)
 313                                 goto trunc;
 314                         printf("pt=0x%02x, pl=%d, pb=", *(p - 2), pl);
 315                         while (pl-- > 0)
 316                                 printf(" %02x", *p++);
 317                         TCHECK2(*p, 2);
 318                         if (p + 2 > endp)
 319                                 goto trunc;
 320                         al = (*p << 8) + *(p + 1);
 321                         printf(", al=%d, a=", al);
 322                         p += 2;
 323                         TCHECK2(*p, al);
 324                         if (p + al > endp)
 325                                 goto trunc;
 326                         while (al-- > 0)
 327                                 printf(" %02x", *p++);
 328                 }
 329                 num--;
 330                 if (num)
 331                         printf(" ");
 332         }
 333
 334         return 0;
 335
 336 trunc:
 337         return -1;
 338 }
 339
 340
 341 static int
 342 cdp_print_prefixes(const u_char * p, int l)
 343 {
 344         if (l % 5)
 345                 goto trunc;
 346
 347         printf(" IPv4 Prefixes (%d):", l / 5);
 348
 349         while (l > 0) {
 350                 printf(" %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]);
 351                 l -= 5;
 352                 p += 5;
 353         }
 354
 355         return 0;
 356
 357 trunc:
 358         return -1;
 359 }
 360
 361 /* read in a <n>-byte number, MSB first
 362  * (of course this can handle max sizeof(long))
 363  */
 364 static unsigned long cdp_get_number(const u_char * p, int l)
 365 {
 366     unsigned long res=0;
 367     while( l>0 )
 368     {
 369         res = (res<<8) + *p;
 370         p++; l--;
 371     }
 372     return res;
 373 }