_vrrp.c

This directory contains source code for tcpdump, a tool for network monitoring and data acquisition

/*
 * Copyright (c) 2000 William C. Fenner.
 *                All rights reserved.
 *
 * Kevin Steves <[e-mail]> July 2000
 * Modified to:
 * - print version, type string and packet length
 * - print IP address count if > 1 (-v)
 * - verify checksum (-v)
 * - print authentication string (-v)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code
 * distributions retain the above copyright notice and this paragraph
 * in its entirety, and (2) distributions including binary code include
 * the above copyright notice and this paragraph in its entirety in
 * the documentation or other materials provided with the distribution.
 * The name of William C. Fenner may not be used to endorse or
 * promote products derived from this software without specific prior
 * written permission.  THIS SOFTWARE IS PROVIDED ``AS IS'' AND
 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE.
 */

#if 0
static const char rcsid[] = "@(#) $Header: /tcpdump/master/tcpdump/print-vrrp.c,v 1.3 2000/10/10 05:05:08 guy Exp $";
#endif

#include <stdio.h>
#include <stdlib.h>
#include <netinet/in.h>

#include "interfac.h"
#include "extract.h"
#include "a2name.h"

/*
 * RFC 2338:
 *     0                   1                   2                   3
 *     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |Version| Type  | Virtual Rtr ID|   Priority    | Count IP Addrs|
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |   Auth Type   |   Adver Int   |          Checksum             |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                         IP Address (1)                        |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                            .                                  |
 *    |                            .                                  |
 *    |                            .                                  |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                         IP Address (n)                        |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                     Authentication Data (1)                   |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *    |                     Authentication Data (2)                   |
 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
void vrrp_print (const u_char * bp, u_int len, u_int ttl)
{
  int   version, type, auth_type;
  char *type_s;

  TCHECK (bp[0]);
  version = (bp[0] & 0xf0) >> 4;
  type = bp[0] & 0x0f;
  if (type == 1)
       type_s = "advertise";
  else type_s = "unknown";

  PRINTF ("VRRPv%d-%s %d: ", version, type_s, len);
  if (ttl != 255)
     PRINTF ("[ttl=%d!] ", ttl);

  if (version != 2 || type != 1)
     return;

  TCHECK (bp[2]);
  PRINTF ("vrid=%d prio=%d", bp[1], bp[2]);
  TCHECK (bp[5]);
  auth_type = bp[4];
  if (auth_type != 0)
     PRINTF (" authtype=%d", auth_type);

  PRINTF (" intvl=%d", bp[5]);

  if (vflag)
  {
    int naddrs = bp[3];
    int i;
    char c;

    if (TTEST2 (bp[0], len) && in_cksum ((const u_short *) bp, len, 0))
       PRINTF (" (bad vrrp cksum %x!)", EXTRACT_16BITS (&bp[6]));
    PUTS (" addrs");
    if (naddrs > 1)
       PRINTF ("(%d)", naddrs);
    PUTCHAR (':');
    c = ' ';
    bp += 8;
    for (i = 0; i < naddrs; i++)
    {
      TCHECK (bp[3]);
      PRINTF ("%c%s", c, ipaddr_string (bp));
      c = ',';
      bp += 4;
    }
    if (auth_type == 1)
    {                           /* simple text password */
      TCHECK (bp[7]);
      PRINTF (" auth %.8s", bp);
    }
  }
  return;
trunc:
  PUTS ("[|vrrp]");
}