xref: /freebsd-src/contrib/tcpdump/print-carp.c (revision 0a7e5f1f02aad2ff5fff1c60f44c6975fd07e1d9)
1cac3dcd5SXin LI /*	$OpenBSD: print-carp.c,v 1.6 2009/10/27 23:59:55 deraadt Exp $	*/
2cac3dcd5SXin LI 
3cac3dcd5SXin LI /*
4cac3dcd5SXin LI  * Copyright (c) 2000 William C. Fenner.
5cac3dcd5SXin LI  *                All rights reserved.
6cac3dcd5SXin LI  *
7cac3dcd5SXin LI  * Kevin Steves <ks@hp.se> July 2000
8cac3dcd5SXin LI  * Modified to:
9cac3dcd5SXin LI  * - print version, type string and packet length
10cac3dcd5SXin LI  * - print IP address count if > 1 (-v)
11cac3dcd5SXin LI  * - verify checksum (-v)
12cac3dcd5SXin LI  * - print authentication string (-v)
13cac3dcd5SXin LI  *
14cac3dcd5SXin LI  * Copyright (c) 2011 Advanced Computing Technologies
15cac3dcd5SXin LI  * George V. Neille-Neil
16cac3dcd5SXin LI  *
17cac3dcd5SXin LI  * Modified to:
18cac3dcd5SXin LI  * - work correctly with CARP
19cac3dcd5SXin LI  * - compile into the latest tcpdump
20cac3dcd5SXin LI  * - print out the counter
21cac3dcd5SXin LI  *
22cac3dcd5SXin LI  * Redistribution and use in source and binary forms, with or without
23cac3dcd5SXin LI  * modification, are permitted provided that: (1) source code
24cac3dcd5SXin LI  * distributions retain the above copyright notice and this paragraph
25cac3dcd5SXin LI  * in its entirety, and (2) distributions including binary code include
26cac3dcd5SXin LI  * the above copyright notice and this paragraph in its entirety in
27cac3dcd5SXin LI  * the documentation or other materials provided with the distribution.
28cac3dcd5SXin LI  * The name of William C. Fenner may not be used to endorse or
29cac3dcd5SXin LI  * promote products derived from this software without specific prior
30cac3dcd5SXin LI  * written permission.  THIS SOFTWARE IS PROVIDED ``AS IS'' AND
31cac3dcd5SXin LI  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
32cac3dcd5SXin LI  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
33cac3dcd5SXin LI  * FOR A PARTICULAR PURPOSE.
34cac3dcd5SXin LI  *
35cac3dcd5SXin LI  */
36cac3dcd5SXin LI 
373340d773SGleb Smirnoff /* \summary: Common Address Redundancy Protocol (CARP) printer */
383340d773SGleb Smirnoff 
39ee67461eSJoseph Mingrone #include <config.h>
40cac3dcd5SXin LI 
41ee67461eSJoseph Mingrone #include "netdissect-stdinc.h"
42cac3dcd5SXin LI 
433340d773SGleb Smirnoff #include "netdissect.h" /* for checksum structure and functions */
44cac3dcd5SXin LI #include "extract.h"
45cac3dcd5SXin LI 
46cac3dcd5SXin LI void
47ee67461eSJoseph Mingrone carp_print(netdissect_options *ndo, const u_char *bp, u_int len, u_int ttl)
48cac3dcd5SXin LI {
49ee67461eSJoseph Mingrone 	u_int version, type;
50cac3dcd5SXin LI 	const char *type_s;
51cac3dcd5SXin LI 
52ee67461eSJoseph Mingrone 	ndo->ndo_protocol = "carp";
53*0a7e5f1fSJoseph Mingrone 	nd_print_protocol_caps(ndo);
54ee67461eSJoseph Mingrone 	version = (GET_U_1(bp) & 0xf0) >> 4;
55ee67461eSJoseph Mingrone 	type = GET_U_1(bp) & 0x0f;
56cac3dcd5SXin LI 	if (type == 1)
57cac3dcd5SXin LI 		type_s = "advertise";
58cac3dcd5SXin LI 	else
59cac3dcd5SXin LI 		type_s = "unknown";
60*0a7e5f1fSJoseph Mingrone 	ND_PRINT("v%u-%s %u: ", version, type_s, len);
61cac3dcd5SXin LI 	if (ttl != 255)
62ee67461eSJoseph Mingrone 		ND_PRINT("[ttl=%u!] ", ttl);
63cac3dcd5SXin LI 	if (version != 2 || type != 1)
64cac3dcd5SXin LI 		return;
65ee67461eSJoseph Mingrone 	ND_PRINT("vhid=%u advbase=%u advskew=%u authlen=%u ",
66ee67461eSJoseph Mingrone 	    GET_U_1(bp + 1), GET_U_1(bp + 5), GET_U_1(bp + 2),
67ee67461eSJoseph Mingrone 	    GET_U_1(bp + 3));
683c602fabSXin LI 	if (ndo->ndo_vflag) {
69cac3dcd5SXin LI 		struct cksum_vec vec[1];
703c602fabSXin LI 		vec[0].ptr = (const uint8_t *)bp;
71cac3dcd5SXin LI 		vec[0].len = len;
72ee67461eSJoseph Mingrone 		if (ND_TTEST_LEN(bp, len) && in_cksum(vec, 1))
73ee67461eSJoseph Mingrone 			ND_PRINT(" (bad carp cksum %x!)",
74ee67461eSJoseph Mingrone 				GET_BE_U_2(bp + 6));
75cac3dcd5SXin LI 	}
76ee67461eSJoseph Mingrone 	ND_PRINT("counter=%" PRIu64, GET_BE_U_8(bp + 8));
77cac3dcd5SXin LI }
78