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[] _U_ =
28    "@(#) $Header: /tcpdump/master/tcpdump/print-vrrp.c,v 1.10 2005-05-06 07:56:54 guy Exp $";
29#endif
30
31#ifdef HAVE_CONFIG_H
32#include "config.h"
33#endif
34
35#include <tcpdump-stdinc.h>
36
37#include <stdio.h>
38#include <stdlib.h>
39
40#include "interface.h"
41#include "extract.h"
42#include "addrtoname.h"
43
44/*
45 * RFC 2338:
46 *     0                   1                   2                   3
47 *     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
48 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49 *    |Version| Type  | Virtual Rtr ID|   Priority    | Count IP Addrs|
50 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51 *    |   Auth Type   |   Adver Int   |          Checksum             |
52 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
53 *    |                         IP Address (1)                        |
54 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
55 *    |                            .                                  |
56 *    |                            .                                  |
57 *    |                            .                                  |
58 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
59 *    |                         IP Address (n)                        |
60 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
61 *    |                     Authentication Data (1)                   |
62 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63 *    |                     Authentication Data (2)                   |
64 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
65 */
66
67/* Type */
68#define	VRRP_TYPE_ADVERTISEMENT	1
69
70static const struct tok type2str[] = {
71	{ VRRP_TYPE_ADVERTISEMENT,	"Advertisement"	},
72	{ 0,				NULL		}
73};
74
75/* Auth Type */
76#define	VRRP_AUTH_NONE		0
77#define	VRRP_AUTH_SIMPLE	1
78#define	VRRP_AUTH_AH		2
79
80static const struct tok auth2str[] = {
81	{ VRRP_AUTH_NONE,		"none"		},
82	{ VRRP_AUTH_SIMPLE,		"simple"	},
83	{ VRRP_AUTH_AH,			"ah"		},
84	{ 0,				NULL		}
85};
86
87void
88vrrp_print(register const u_char *bp, register u_int len, int ttl)
89{
90	int version, type, auth_type;
91	const char *type_s;
92
93	TCHECK(bp[0]);
94	version = (bp[0] & 0xf0) >> 4;
95	type = bp[0] & 0x0f;
96	type_s = tok2str(type2str, "unknown type (%u)", type);
97	printf("VRRPv%u, %s", version, type_s);
98	if (ttl != 255)
99		printf(", (ttl %u)", ttl);
100	if (version != 2 || type != VRRP_TYPE_ADVERTISEMENT)
101		return;
102	TCHECK(bp[2]);
103	printf(", vrid %u, prio %u", bp[1], bp[2]);
104	TCHECK(bp[5]);
105	auth_type = bp[4];
106	printf(", authtype %s", tok2str(auth2str, NULL, auth_type));
107	printf(", intvl %us, length %u", bp[5],len);
108	if (vflag) {
109		int naddrs = bp[3];
110		int i;
111		char c;
112
113		if (TTEST2(bp[0], len)) {
114			struct cksum_vec vec[1];
115
116			vec[0].ptr = bp;
117			vec[0].len = len;
118			if (in_cksum(vec, 1))
119				printf(", (bad vrrp cksum %x)",
120					EXTRACT_16BITS(&bp[6]));
121		}
122		printf(", addrs");
123		if (naddrs > 1)
124			printf("(%d)", naddrs);
125		printf(":");
126		c = ' ';
127		bp += 8;
128		for (i = 0; i < naddrs; i++) {
129			TCHECK(bp[3]);
130			printf("%c%s", c, ipaddr_string(bp));
131			c = ',';
132			bp += 4;
133		}
134		if (auth_type == VRRP_AUTH_SIMPLE) { /* simple text password */
135			TCHECK(bp[7]);
136			printf(" auth \"");
137			if (fn_printn(bp, 8, snapend)) {
138				printf("\"");
139				goto trunc;
140			}
141			printf("\"");
142		}
143	}
144	return;
145trunc:
146	printf("[|vrrp]");
147}
148