xref: /minix3/external/bsd/tcpdump/dist/print-carp.c (revision b636d99d91c3d54204248f643c14627405d4afd1)
1*b636d99dSDavid van Moolenbroek /*	$OpenBSD: print-carp.c,v 1.6 2009/10/27 23:59:55 deraadt Exp $	*/
2*b636d99dSDavid van Moolenbroek 
3*b636d99dSDavid van Moolenbroek /*
4*b636d99dSDavid van Moolenbroek  * Copyright (c) 2000 William C. Fenner.
5*b636d99dSDavid van Moolenbroek  *                All rights reserved.
6*b636d99dSDavid van Moolenbroek  *
7*b636d99dSDavid van Moolenbroek  * Kevin Steves <ks@hp.se> July 2000
8*b636d99dSDavid van Moolenbroek  * Modified to:
9*b636d99dSDavid van Moolenbroek  * - print version, type string and packet length
10*b636d99dSDavid van Moolenbroek  * - print IP address count if > 1 (-v)
11*b636d99dSDavid van Moolenbroek  * - verify checksum (-v)
12*b636d99dSDavid van Moolenbroek  * - print authentication string (-v)
13*b636d99dSDavid van Moolenbroek  *
14*b636d99dSDavid van Moolenbroek  * Copyright (c) 2011 Advanced Computing Technologies
15*b636d99dSDavid van Moolenbroek  * George V. Neille-Neil
16*b636d99dSDavid van Moolenbroek  *
17*b636d99dSDavid van Moolenbroek  * Modified to:
18*b636d99dSDavid van Moolenbroek  * - work correctly with CARP
19*b636d99dSDavid van Moolenbroek  * - compile into the latest tcpdump
20*b636d99dSDavid van Moolenbroek  * - print out the counter
21*b636d99dSDavid van Moolenbroek  *
22*b636d99dSDavid van Moolenbroek  * Redistribution and use in source and binary forms, with or without
23*b636d99dSDavid van Moolenbroek  * modification, are permitted provided that: (1) source code
24*b636d99dSDavid van Moolenbroek  * distributions retain the above copyright notice and this paragraph
25*b636d99dSDavid van Moolenbroek  * in its entirety, and (2) distributions including binary code include
26*b636d99dSDavid van Moolenbroek  * the above copyright notice and this paragraph in its entirety in
27*b636d99dSDavid van Moolenbroek  * the documentation or other materials provided with the distribution.
28*b636d99dSDavid van Moolenbroek  * The name of William C. Fenner may not be used to endorse or
29*b636d99dSDavid van Moolenbroek  * promote products derived from this software without specific prior
30*b636d99dSDavid van Moolenbroek  * written permission.  THIS SOFTWARE IS PROVIDED ``AS IS'' AND
31*b636d99dSDavid van Moolenbroek  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
32*b636d99dSDavid van Moolenbroek  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
33*b636d99dSDavid van Moolenbroek  * FOR A PARTICULAR PURPOSE.
34*b636d99dSDavid van Moolenbroek  *
35*b636d99dSDavid van Moolenbroek  */
36*b636d99dSDavid van Moolenbroek 
37*b636d99dSDavid van Moolenbroek #define NETDISSECT_REWORKED
38*b636d99dSDavid van Moolenbroek #ifdef HAVE_CONFIG_H
39*b636d99dSDavid van Moolenbroek #include "config.h"
40*b636d99dSDavid van Moolenbroek #endif
41*b636d99dSDavid van Moolenbroek 
42*b636d99dSDavid van Moolenbroek #include <tcpdump-stdinc.h>
43*b636d99dSDavid van Moolenbroek 
44*b636d99dSDavid van Moolenbroek #include "interface.h" /* for checksum structure and functions */
45*b636d99dSDavid van Moolenbroek #include "extract.h"
46*b636d99dSDavid van Moolenbroek 
47*b636d99dSDavid van Moolenbroek void
carp_print(netdissect_options * ndo,register const u_char * bp,register u_int len,int ttl)48*b636d99dSDavid van Moolenbroek carp_print(netdissect_options *ndo, register const u_char *bp, register u_int len, int ttl)
49*b636d99dSDavid van Moolenbroek {
50*b636d99dSDavid van Moolenbroek 	int version, type;
51*b636d99dSDavid van Moolenbroek 	const char *type_s;
52*b636d99dSDavid van Moolenbroek 
53*b636d99dSDavid van Moolenbroek 	ND_TCHECK(bp[0]);
54*b636d99dSDavid van Moolenbroek 	version = (bp[0] & 0xf0) >> 4;
55*b636d99dSDavid van Moolenbroek 	type = bp[0] & 0x0f;
56*b636d99dSDavid van Moolenbroek 	if (type == 1)
57*b636d99dSDavid van Moolenbroek 		type_s = "advertise";
58*b636d99dSDavid van Moolenbroek 	else
59*b636d99dSDavid van Moolenbroek 		type_s = "unknown";
60*b636d99dSDavid van Moolenbroek 	ND_PRINT((ndo, "CARPv%d-%s %d: ", version, type_s, len));
61*b636d99dSDavid van Moolenbroek 	if (ttl != 255)
62*b636d99dSDavid van Moolenbroek 		ND_PRINT((ndo, "[ttl=%d!] ", ttl));
63*b636d99dSDavid van Moolenbroek 	if (version != 2 || type != 1)
64*b636d99dSDavid van Moolenbroek 		return;
65*b636d99dSDavid van Moolenbroek 	ND_TCHECK(bp[2]);
66*b636d99dSDavid van Moolenbroek 	ND_TCHECK(bp[5]);
67*b636d99dSDavid van Moolenbroek 	ND_PRINT((ndo, "vhid=%d advbase=%d advskew=%d authlen=%d ",
68*b636d99dSDavid van Moolenbroek 	    bp[1], bp[5], bp[2], bp[3]));
69*b636d99dSDavid van Moolenbroek 	if (ndo->ndo_vflag) {
70*b636d99dSDavid van Moolenbroek 		struct cksum_vec vec[1];
71*b636d99dSDavid van Moolenbroek 		vec[0].ptr = (const uint8_t *)bp;
72*b636d99dSDavid van Moolenbroek 		vec[0].len = len;
73*b636d99dSDavid van Moolenbroek 		if (ND_TTEST2(bp[0], len) && in_cksum(vec, 1))
74*b636d99dSDavid van Moolenbroek 			ND_PRINT((ndo, " (bad carp cksum %x!)",
75*b636d99dSDavid van Moolenbroek 				EXTRACT_16BITS(&bp[6])));
76*b636d99dSDavid van Moolenbroek 	}
77*b636d99dSDavid van Moolenbroek 	ND_PRINT((ndo, "counter=%" PRIu64, EXTRACT_64BITS(&bp[8])));
78*b636d99dSDavid van Moolenbroek 
79*b636d99dSDavid van Moolenbroek 	return;
80*b636d99dSDavid van Moolenbroek trunc:
81*b636d99dSDavid van Moolenbroek 	ND_PRINT((ndo, "[|carp]"));
82*b636d99dSDavid van Moolenbroek }
83