xref: /aosp_15_r20/external/tcpdump/print-ripng.c (revision 05b00f6010a2396e3db2409989fc67270046269f)

/*
 * Copyright (c) 1989, 1990, 1991, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * 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, (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, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may 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.
 */

/* \summary: IPv6 Routing Information Protocol (RIPng) printer */

/* specification: RFC 2080 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "netdissect-stdinc.h"

#include "netdissect.h"
#include "addrtoname.h"
#include "extract.h"

/*
 * Copyright (C) 1995, 1996, 1997 and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
#define	RIP6_VERSION	1

#define	RIP6_REQUEST	1
#define	RIP6_RESPONSE	2

struct netinfo6 {
	nd_ipv6		rip6_dest;
	nd_uint16_t	rip6_tag;
	nd_uint8_t	rip6_plen;
	nd_uint8_t	rip6_metric;
};

struct	rip6 {
	nd_uint8_t	rip6_cmd;
	nd_uint8_t	rip6_vers;
	nd_byte		rip6_res1[2];
	struct netinfo6	rip6_nets[1];
};

#define	HOPCNT_INFINITY6	16

static int ND_IN6_IS_ADDR_UNSPECIFIED(const nd_ipv6 *addr)
{
    static const nd_ipv6 in6addr_any_val = { 0 };        /* :: */
    return (memcmp(addr, &in6addr_any_val, sizeof(*addr)) == 0);
}

static void
rip6_entry_print(netdissect_options *ndo,
                 const struct netinfo6 *ni, const u_int print_metric)
{
	uint16_t tag;
	uint8_t metric;

	ND_PRINT("%s/%u", GET_IP6ADDR_STRING(ni->rip6_dest),
	         GET_U_1(ni->rip6_plen));
	tag = GET_BE_U_2(ni->rip6_tag);
	if (tag)
		ND_PRINT(" [%u]", tag);
	metric = GET_U_1(ni->rip6_metric);
	if (metric && print_metric)
		ND_PRINT(" (%u)", metric);
}

void
ripng_print(netdissect_options *ndo, const u_char *dat, unsigned int length)
{
	const struct rip6 *rp = (const struct rip6 *)dat;
	uint8_t cmd, vers;
	const struct netinfo6 *ni;
	unsigned int length_left;
	u_int j;

	ndo->ndo_protocol = "ripng";
	vers = GET_U_1(rp->rip6_vers);
	if (vers != RIP6_VERSION) {
		nd_print_protocol(ndo);
		ND_PRINT(" [version %u, must be %u]", vers, RIP6_VERSION);
		goto invalid;
	}
	cmd = GET_U_1(rp->rip6_cmd);
	switch (cmd) {

	case RIP6_REQUEST:
		length_left = length;
		if (length_left < (sizeof(struct rip6) - sizeof(struct netinfo6)))
			goto invalid;
		length_left -= (sizeof(struct rip6) - sizeof(struct netinfo6));
		j = length_left / sizeof(*ni);
		if (j == 1) {
			if (GET_U_1(rp->rip6_nets->rip6_metric) == HOPCNT_INFINITY6
			    && ND_IN6_IS_ADDR_UNSPECIFIED(&rp->rip6_nets->rip6_dest)) {
				ND_PRINT(" ripng-req dump");
				break;
			}
		}
		if (j * sizeof(*ni) != length_left)
			ND_PRINT(" ripng-req %u[%u]:", j, length);
		else
			ND_PRINT(" ripng-req %u:", j);
		for (ni = rp->rip6_nets; length_left >= sizeof(*ni);
		    length_left -= sizeof(*ni), ++ni) {
			if (ndo->ndo_vflag > 1)
				ND_PRINT("\n\t");
			else
				ND_PRINT(" ");
			rip6_entry_print(ndo, ni, FALSE);
		}
		if (length_left != 0)
			goto invalid;
		break;
	case RIP6_RESPONSE:
		length_left = length;
		if (length_left < (sizeof(struct rip6) - sizeof(struct netinfo6)))
			goto invalid;
		length_left -= (sizeof(struct rip6) - sizeof(struct netinfo6));
		j = length_left / sizeof(*ni);
		if (j * sizeof(*ni) != length_left)
			ND_PRINT(" ripng-resp %u[%u]:", j, length);
		else
			ND_PRINT(" ripng-resp %u:", j);
		for (ni = rp->rip6_nets; length_left >= sizeof(*ni);
		    length_left -= sizeof(*ni), ++ni) {
			if (ndo->ndo_vflag > 1)
				ND_PRINT("\n\t");
			else
				ND_PRINT(" ");
			rip6_entry_print(ndo, ni, TRUE);
		}
		if (length_left != 0)
			goto invalid;
		break;
	default:
		ND_PRINT(" ripng-%u ?? %u", cmd, length);
		goto invalid;
	}
	return;

invalid:
	nd_print_invalid(ndo);
}