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

   1 /*
   2  * Copyright (c) 2001 William C. Fenner.
   3  *                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
   7  * distributions retain the above copyright notice and this paragraph
   8  * in its entirety, and (2) distributions including binary code include
   9  * the above copyright notice and this paragraph in its entirety in
  10  * the documentation or other materials provided with the distribution.
  11  * The name of William C. Fenner may not be used to endorse or
  12  * promote products derived from this software without specific prior
  13  * written permission.  THIS SOFTWARE IS PROVIDED ``AS IS'' AND
  14  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
  15  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  16  * FOR A PARTICULAR PURPOSE.
  17  */
  18
  19 #define NETDISSECT_REWORKED
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include <tcpdump-stdinc.h>
  25
  26 #include "interface.h"
  27 #include "addrtoname.h"
  28 #include "extract.h"
  29
  30 #define MSDP_TYPE_MAX   7
  31
  32 void
  33 msdp_print(netdissect_options *ndo, const u_char *sp, u_int length)
  34 {
  35         unsigned int type, len;
  36
  37         ND_TCHECK2(*sp, 3);
  38         /* See if we think we're at the beginning of a compound packet */
  39         type = *sp;
  40         len = EXTRACT_16BITS(sp + 1);
  41         if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX)
  42                 goto trunc;     /* not really truncated, but still not decodable */
  43         ND_PRINT((ndo, " msdp:"));
  44         while (length > 0) {
  45                 ND_TCHECK2(*sp, 3);
  46                 type = *sp;
  47                 len = EXTRACT_16BITS(sp + 1);
  48                 if (len > 1400 || ndo->ndo_vflag)
  49                         ND_PRINT((ndo, " [len %u]", len));
  50                 if (len < 3)
  51                         goto trunc;
  52                 sp += 3;
  53                 length -= 3;
  54                 switch (type) {
  55                 case 1: /* IPv4 Source-Active */
  56                 case 3: /* IPv4 Source-Active Response */
  57                         if (type == 1)
  58                                 ND_PRINT((ndo, " SA"));
  59                         else
  60                                 ND_PRINT((ndo, " SA-Response"));
  61                         ND_TCHECK(*sp);
  62                         ND_PRINT((ndo, " %u entries", *sp));
  63                         if ((u_int)((*sp * 12) + 8) < len) {
  64                                 ND_PRINT((ndo, " [w/data]"));
  65                                 if (ndo->ndo_vflag > 1) {
  66                                         ND_PRINT((ndo, " "));
  67                                         ip_print(ndo, sp + *sp * 12 + 8 - 3,
  68                                                  len - (*sp * 12 + 8));
  69                                 }
  70                         }
  71                         break;
  72                 case 2:
  73                         ND_PRINT((ndo, " SA-Request"));
  74                         ND_TCHECK2(*sp, 5);
  75                         ND_PRINT((ndo, " for %s", ipaddr_string(ndo, sp + 1)));
  76                         break;
  77                 case 4:
  78                         ND_PRINT((ndo, " Keepalive"));
  79                         if (len != 3)
  80                                 ND_PRINT((ndo, "[len=%d] ", len));
  81                         break;
  82                 case 5:
  83                         ND_PRINT((ndo, " Notification"));
  84                         break;
  85                 default:
  86                         ND_PRINT((ndo, " [type=%d len=%d]", type, len));
  87                         break;
  88                 }
  89                 sp += (len - 3);
  90                 length -= (len - 3);
  91         }
  92         return;
  93 trunc:
  94         ND_PRINT((ndo, " [|msdp]"));
  95 }
  96
  97 /*
  98  * Local Variables:
  99  * c-style: whitesmith
 100  * c-basic-offset: 8
 101  * End:
 102  */