print-vrrp.c revision 75115 
1/*
2 * Copyright (c) 2000 William C. Fenner.
3 *                All rights reserved.
4 *
5 * Kevin Steves <ks@hp.se> July 2000
6 * Modified to:
7 * - print version, type string and packet length
8 * - print IP address count if > 1 (-v)
9 * - verify checksum (-v)
10 * - print authentication string (-v)
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that: (1) source code
14 * distributions retain the above copyright notice and this paragraph
15 * in its entirety, and (2) distributions including binary code include
16 * the above copyright notice and this paragraph in its entirety in
17 * the documentation or other materials provided with the distribution.
18 * The name of William C. Fenner may not be used to endorse or
19 * promote products derived from this software without specific prior
20 * written permission.  THIS SOFTWARE IS PROVIDED ``AS IS'' AND
21 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
22 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE.
24 */
25
26#ifndef lint
27static const char rcsid[] =
28    "@(#) $Header: /tcpdump/master/tcpdump/print-vrrp.c,v 1.3 2000/10/10 05:05:08 guy Exp $";
29#endif
30
31#ifdef HAVE_CONFIG_H
32#include "config.h"
33#endif
34
35#include <stdio.h>
36#include <stdlib.h>
37#include <unistd.h>
38
39#include <netinet/in.h>
40
41#include "interface.h"
42#include "extract.h"
43#include "addrtoname.h"
44
45/*
46 * RFC 2338:
47 *     0                   1                   2                   3
48 *     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
49 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
50 *    |Version| Type  | Virtual Rtr ID|   Priority    | Count IP Addrs|
51 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
52 *    |   Auth Type   |   Adver Int   |          Checksum             |
53 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
54 *    |                         IP Address (1)                        |
55 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
56 *    |                            .                                  |
57 *    |                            .                                  |
58 *    |                            .                                  |
59 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
60 *    |                         IP Address (n)                        |
61 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
62 *    |                     Authentication Data (1)                   |
63 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
64 *    |                     Authentication Data (2)                   |
65 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
66 */
67void
68vrrp_print(register const u_char *bp, register u_int len, int ttl)
69{
70	int version, type, auth_type;
71	char *type_s;
72
73	TCHECK(bp[0]);
74	version = (bp[0] & 0xf0) >> 4;
75	type = bp[0] & 0x0f;
76	if (type == 1)
77		type_s = "advertise";
78	else
79		type_s = "unknown";
80	printf("VRRPv%d-%s %d: ", version, type_s, len);
81	if (ttl != 255)
82		printf("[ttl=%d!] ", ttl);
83	if (version != 2 || type != 1)
84		return;
85	TCHECK(bp[2]);
86	printf("vrid=%d prio=%d", bp[1], bp[2]);
87	TCHECK(bp[5]);
88	auth_type = bp[4];
89	if (auth_type != 0)
90		printf(" authtype=%d", auth_type);
91	printf(" intvl=%d", bp[5]);
92	if (vflag) {
93		int naddrs = bp[3];
94		int i;
95		char c;
96
97		if (TTEST2(bp[0], len) && in_cksum((const u_short*)bp, len, 0))
98			printf(" (bad vrrp cksum %x!)",
99				EXTRACT_16BITS(&bp[6]));
100		printf(" addrs");
101		if (naddrs > 1)
102			printf("(%d)", naddrs);
103		printf(":");
104		c = ' ';
105		bp += 8;
106		for (i = 0; i < naddrs; i++) {
107			TCHECK(bp[3]);
108			printf("%c%s", c, ipaddr_string(bp));
109			c = ',';
110			bp += 4;
111		}
112		if (auth_type == 1) { /* simple text password */
113			TCHECK(bp[7]);
114			printf(" auth %.8s", bp);
115		}
116	}
117	return;
118trunc:
119	printf("[|vrrp]");
120}
121