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 #ifndef lint
  19 static const char rcsid[] =
  20     "@(#) $Header: /tcpdump/master/tcpdump/print-msdp.c,v 1.2 2001-12-10 08:06:40 guy Exp $";
  21 #endif
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <unistd.h>
  30
  31 #include <netinet/in.h>
  32
  33 #include "interface.h"
  34 #include "addrtoname.h"
  35 #include "extract.h"
  36
  37 #define MSDP_TYPE_MAX   7
  38
  39 void
  40 msdp_print(const unsigned char *sp, u_int length)
  41 {
  42         unsigned int type, len;
  43
  44         TCHECK2(*sp, 3);
  45         /* See if we think we're at the beginning of a compound packet */
  46         type = *sp;
  47         len = EXTRACT_16BITS(sp + 1);
  48         if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX)
  49                 goto trunc;     /* not really truncated, but still not decodable */
  50         (void)printf(" msdp:");
  51         while (length > 0) {
  52                 TCHECK2(*sp, 3);
  53                 type = *sp;
  54                 len = EXTRACT_16BITS(sp + 1);
  55                 if (len > 1400 || vflag)
  56                         printf(" [len %d]", len);
  57                 if (len < 3)
  58                         goto trunc;
  59                 sp += 3;
  60                 length -= 3;
  61                 switch (type) {
  62                 case 1: /* IPv4 Source-Active */
  63                 case 3: /* IPv4 Source-Active Response */
  64                         if (type == 1)
  65                                 (void)printf(" SA");
  66                         else
  67                                 (void)printf(" SA-Response");
  68                         TCHECK(*sp);
  69                         (void)printf(" %d entries", *sp);
  70                         if (*sp * 12 + 8 < len) {
  71                                 (void)printf(" [w/data]");
  72                                 if (vflag > 1) {
  73                                         (void)printf(" ");
  74                                         ip_print(sp + *sp * 12 + 8 - 3,
  75                                                  len - (*sp * 12 + 8));
  76                                 }
  77                         }
  78                         break;
  79                 case 2:
  80                         (void)printf(" SA-Request");
  81                         TCHECK2(*sp, 5);
  82                         (void)printf(" for %s", ipaddr_string(sp + 1));
  83                         break;
  84                 case 4:
  85                         (void)printf(" Keepalive");
  86                         if (len != 3)
  87                                 (void)printf("[len=%d] ", len);
  88                         break;
  89                 case 5:
  90                         (void)printf(" Notification");
  91                         break;
  92                 default:
  93                         (void)printf(" [type=%d len=%d]", type, len);
  94                         break;
  95                 }
  96                 sp += (len - 3);
  97                 length -= (len - 3);
  98         }
  99         return;
 100 trunc:
 101         (void)printf(" [|msdp]");
 102 }