The Tcpdump Group git mirrors - tcpdump/blob - print-dtp.c

   1 /*
   2  * Copyright (c) 1998-2007 The TCPDUMP project
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that: (1) source code
   6  * distributions retain the above copyright notice and this paragraph
   7  * in its entirety, and (2) distributions including binary code include
   8  * the above copyright notice and this paragraph in its entirety in
   9  * the documentation or other materials provided with the distribution.
  10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
  11  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
  12  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  13  * FOR A PARTICULAR PURPOSE.
  14  *
  15  * Dynamic Trunk Protocol (DTP)
  16  *
  17  * Original code by Carles Kishimoto <carles.kishimoto@gmail.com>
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include <tcpdump-stdinc.h>
  25
  26 #include "netdissect.h"
  27 #include "addrtoname.h"
  28 #include "extract.h"
  29
  30 #define DTP_HEADER_LEN                  1
  31 #define DTP_DOMAIN_TLV                  0x0001
  32 #define DTP_STATUS_TLV                  0x0002
  33 #define DTP_DTP_TYPE_TLV                0x0003
  34 #define DTP_NEIGHBOR_TLV                0x0004
  35
  36 static const struct tok dtp_tlv_values[] = {
  37     { DTP_DOMAIN_TLV, "Domain TLV"},
  38     { DTP_STATUS_TLV, "Status TLV"},
  39     { DTP_DTP_TYPE_TLV, "DTP type TLV"},
  40     { DTP_NEIGHBOR_TLV, "Neighbor TLV"},
  41     { 0, NULL}
  42 };
  43
  44 void
  45 dtp_print (netdissect_options *ndo, const u_char *pptr, u_int length)
  46 {
  47     int type, len;
  48     const u_char *tptr;
  49
  50     if (length < DTP_HEADER_LEN)
  51         goto trunc;
  52
  53     tptr = pptr;
  54
  55     if (!ND_TTEST2(*tptr, DTP_HEADER_LEN))
  56         goto trunc;
  57
  58     ND_PRINT((ndo, "DTPv%u, length %u",
  59            (*tptr),
  60            length));
  61
  62     /*
  63      * In non-verbose mode, just print version.
  64      */
  65     if (ndo->ndo_vflag < 1) {
  66         return;
  67     }
  68
  69     tptr += DTP_HEADER_LEN;
  70
  71     while (tptr < (pptr+length)) {
  72
  73         if (!ND_TTEST2(*tptr, 4))
  74             goto trunc;
  75
  76         type = EXTRACT_16BITS(tptr);
  77         len  = EXTRACT_16BITS(tptr+2);
  78
  79         /* infinite loop check */
  80         if (type == 0 || len == 0) {
  81             return;
  82         }
  83
  84         ND_PRINT((ndo, "\n\t%s (0x%04x) TLV, length %u",
  85                tok2str(dtp_tlv_values, "Unknown", type),
  86                type, len));
  87
  88         switch (type) {
  89         case DTP_DOMAIN_TLV:
  90                 ND_PRINT((ndo, ", %s", tptr+4));
  91                 break;
  92
  93         case DTP_STATUS_TLV:
  94         case DTP_DTP_TYPE_TLV:
  95                 ND_PRINT((ndo, ", 0x%x", *(tptr+4)));
  96                 break;
  97
  98         case DTP_NEIGHBOR_TLV:
  99                 ND_PRINT((ndo, ", %s", etheraddr_string(tptr+4)));
 100                 break;
 101
 102         default:
 103             break;
 104         }
 105         tptr += len;
 106     }
 107
 108     return;
 109
 110  trunc:
 111     ND_PRINT((ndo, "[|dtp]"));
 112 }
 113
 114 /*
 115  * Local Variables:
 116  * c-style: whitesmith
 117  * c-basic-offset: 4
 118  * End:
 119  */