contrib/tcpdump-3.8.3/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 #ifndef lint
  19 static const char rcsid[] _U_ =
  20     "@(#) $Header: /tcpdump/master/tcpdump/print-msdp.c,v 1.4.2.2 2003/11/16 08:51:34 guy Exp $";
  21 #endif
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <tcpdump-stdinc.h>
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31
  32 #include "interface.h"
  33 #include "addrtoname.h"
  34 #include "extract.h"
  35
  36 #define MSDP_TYPE_MAX   7
  37
  38 void
  39 msdp_print(const unsigned char *sp, u_int length)
  40 {
  41         unsigned int type, len;
  42
  43         TCHECK2(*sp, 3);
  44         /* See if we think we're at the beginning of a compound packet */
  45         type = *sp;
  46         len = EXTRACT_16BITS(sp + 1);
  47         if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX)
  48                 goto trunc;     /* not really truncated, but still not decodable */
  49         (void)printf(" msdp:");
  50         while (length > 0) {
  51                 TCHECK2(*sp, 3);
  52                 type = *sp;
  53                 len = EXTRACT_16BITS(sp + 1);
  54                 if (len > 1400 || vflag)
  55                         printf(" [len %u]", len);
  56                 if (len < 3)
  57                         goto trunc;
  58                 sp += 3;
  59                 length -= 3;
  60                 switch (type) {
  61                 case 1: /* IPv4 Source-Active */
  62                 case 3: /* IPv4 Source-Active Response */
  63                         if (type == 1)
  64                                 (void)printf(" SA");
  65                         else
  66                                 (void)printf(" SA-Response");
  67                         TCHECK(*sp);
  68                         (void)printf(" %u entries", *sp);
  69                         if ((u_int)((*sp * 12) + 8) < len) {
  70                                 (void)printf(" [w/data]");
  71                                 if (vflag > 1) {
  72                                         (void)printf(" ");
  73                                         ip_print(sp + *sp * 12 + 8 - 3,
  74                                                  len - (*sp * 12 + 8));
  75                                 }
  76                         }
  77                         break;
  78                 case 2:
  79                         (void)printf(" SA-Request");
  80                         TCHECK2(*sp, 5);
  81                         (void)printf(" for %s", ipaddr_string(sp + 1));
  82                         break;
  83                 case 4:
  84                         (void)printf(" Keepalive");
  85                         if (len != 3)
  86                                 (void)printf("[len=%d] ", len);
  87                         break;
  88                 case 5:
  89                         (void)printf(" Notification");
  90                         break;
  91                 default:
  92                         (void)printf(" [type=%d len=%d]", type, len);
  93                         break;
  94                 }
  95                 sp += (len - 3);
  96                 length -= (len - 3);
  97         }
  98         return;
  99 trunc:
 100         (void)printf(" [|msdp]");
 101 }