/*
* Copyright (c) 2000 William C. Fenner.
* All rights reserved.
*
* Kevin Steves <ks@hp.se> July 2000
* Modified to:
* - print version, type string and packet length
* - print IP address count if > 1 (-v)
* - verify checksum (-v)
* - print authentication string (-v)
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code
* distributions retain the above copyright notice and this paragraph
* in its entirety, and (2) distributions including binary code include
* the above copyright notice and this paragraph in its entirety in
* the documentation or other materials provided with the distribution.
* The name of William C. Fenner may not be used to endorse or
* promote products derived from this software without specific prior
* written permission. THIS SOFTWARE IS PROVIDED ``AS IS'' AND
* WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
* LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE.
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: print-vrrp.c,v 1.6 2017/02/05 04:05:05 spz Exp $");
#endif
/* \summary: Virtual Router Redundancy Protocol (VRRP) printer */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <netdissect-stdinc.h>
#include "netdissect.h"
#include "extract.h"
#include "addrtoname.h"
#include "ip.h"
#include "ipproto.h"
/*
* RFC 2338 (VRRP v2):
*
* 0 1 2 3
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |Version| Type | Virtual Rtr ID| Priority | Count IP Addrs|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Auth Type | Adver Int | Checksum |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | IP Address (1) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | . |
* | . |
* | . |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | IP Address (n) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data (1) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Authentication Data (2) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
*
* RFC 5798 (VRRP v3):
*
* 0 1 2 3
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | IPv4 Fields or IPv6 Fields |
* ... ...
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |Version| Type | Virtual Rtr ID| Priority |Count IPvX Addr|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |(rsvd) | Max Adver Int | Checksum |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* + +
* | IPvX Address(es) |
* + +
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
/* Type */
#define VRRP_TYPE_ADVERTISEMENT 1
static const struct tok type2str[] = {
{ VRRP_TYPE_ADVERTISEMENT, "Advertisement" },
{ 0, NULL }
};
/* Auth Type */
#define VRRP_AUTH_NONE 0
#define VRRP_AUTH_SIMPLE 1
#define VRRP_AUTH_AH 2
static const struct tok auth2str[] = {
{ VRRP_AUTH_NONE, "none" },
{ VRRP_AUTH_SIMPLE, "simple" },
{ VRRP_AUTH_AH, "ah" },
{ 0, NULL }
};
void
vrrp_print(netdissect_options *ndo,
register const u_char *bp, register u_int len,
register const u_char *bp2, int ttl)
{
int version, type, auth_type = VRRP_AUTH_NONE; /* keep compiler happy */
const char *type_s;
ND_TCHECK(bp[0]);
version = (bp[0] & 0xf0) >> 4;
type = bp[0] & 0x0f;
type_s = tok2str(type2str, "unknown type (%u)", type);
ND_PRINT((ndo, "VRRPv%u, %s", version, type_s));
if (ttl != 255)
ND_PRINT((ndo, ", (ttl %u)", ttl));
if (version < 2 || version > 3 || type != VRRP_TYPE_ADVERTISEMENT)
return;
ND_TCHECK(bp[2]);
ND_PRINT((ndo, ", vrid %u, prio %u", bp[1], bp[2]));
ND_TCHECK(bp[5]);
if (version == 2) {
auth_type = bp[4];
ND_PRINT((ndo, ", authtype %s", tok2str(auth2str, NULL, auth_type)));
ND_PRINT((ndo, ", intvl %us, length %u", bp[5], len));
} else { /* version == 3 */
uint16_t intvl = (bp[4] & 0x0f) << 8 | bp[5];
ND_PRINT((ndo, ", intvl %ucs, length %u", intvl, len));
}
if (ndo->ndo_vflag) {
int naddrs = bp[3];
int i;
char c;
if (version == 2 && ND_TTEST2(bp[0], len)) {
struct cksum_vec vec[1];
vec[0].ptr = bp;
vec[0].len = len;
if (in_cksum(vec, 1))
ND_PRINT((ndo, ", (bad vrrp cksum %x)",
EXTRACT_16BITS(&bp[6])));
}
if (version == 3 && ND_TTEST2(bp[0], len)) {
uint16_t cksum = nextproto4_cksum(ndo, (const struct ip *)bp2, bp,
len, len, IPPROTO_VRRP);
if (cksum)
ND_PRINT((ndo, ", (bad vrrp cksum %x)",
EXTRACT_16BITS(&bp[6])));
}
ND_PRINT((ndo, ", addrs"));
if (naddrs > 1)
ND_PRINT((ndo, "(%d)", naddrs));
ND_PRINT((ndo, ":"));
c = ' ';
bp += 8;
for (i = 0; i < naddrs; i++) {
ND_TCHECK(bp[3]);
ND_PRINT((ndo, "%c%s", c, ipaddr_string(ndo, bp)));
c = ',';
bp += 4;
}
if (version == 2 && auth_type == VRRP_AUTH_SIMPLE) { /* simple text password */
ND_TCHECK(bp[7]);
ND_PRINT((ndo, " auth \""));
if (fn_printn(ndo, bp, 8, ndo->ndo_snapend)) {
ND_PRINT((ndo, "\""));
goto trunc;
}
ND_PRINT((ndo, "\""));
}
}
return;
trunc:
ND_PRINT((ndo, "[|vrrp]"));
}