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
19/* \summary: Multicast Source Discovery Protocol (MSDP) printer */
20
21#ifdef HAVE_CONFIG_H
22#include <config.h>
23#endif
24
25#include "netdissect-stdinc.h"
26
27#include "netdissect.h"
28#include "addrtoname.h"
29#include "extract.h"
30
31#define MSDP_TYPE_MAX	7
32
33void
34msdp_print(netdissect_options *ndo, const u_char *sp, u_int length)
35{
36	unsigned int type, len;
37
38	ndo->ndo_protocol = "msdp";
39	ND_PRINT(": ");
40	nd_print_protocol(ndo);
41	/* See if we think we're at the beginning of a compound packet */
42	type = GET_U_1(sp);
43	len = GET_BE_U_2(sp + 1);
44	if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX)
45		goto trunc;	/* not really truncated, but still not decodable */
46	while (length != 0) {
47		type = GET_U_1(sp);
48		len = GET_BE_U_2(sp + 1);
49		if (len > 1400 || ndo->ndo_vflag)
50			ND_PRINT(" [len %u]", len);
51		if (len < 3)
52			goto trunc;
53		if (length < len)
54			goto trunc;
55		sp += 3;
56		length -= 3;
57		switch (type) {
58		case 1:	/* IPv4 Source-Active */
59		case 3: /* IPv4 Source-Active Response */
60			if (type == 1)
61				ND_PRINT(" SA");
62			else
63				ND_PRINT(" SA-Response");
64			ND_PRINT(" %u entries", GET_U_1(sp));
65			if ((u_int)((GET_U_1(sp) * 12) + 8) < len) {
66				ND_PRINT(" [w/data]");
67				if (ndo->ndo_vflag > 1) {
68					ND_PRINT(" ");
69					ip_print(ndo, sp +
70						 GET_U_1(sp) * 12 + 8 - 3,
71						 len - (GET_U_1(sp) * 12 + 8));
72				}
73			}
74			break;
75		case 2:
76			ND_PRINT(" SA-Request");
77			ND_PRINT(" for %s", GET_IPADDR_STRING(sp + 1));
78			break;
79		case 4:
80			ND_PRINT(" Keepalive");
81			if (len != 3)
82				ND_PRINT("[len=%u] ", len);
83			break;
84		case 5:
85			ND_PRINT(" Notification");
86			break;
87		default:
88			ND_PRINT(" [type=%u len=%u]", type, len);
89			break;
90		}
91		sp += (len - 3);
92		length -= (len - 3);
93	}
94	return;
95trunc:
96	nd_print_trunc(ndo);
97}
98