/* $NetBSD: ifmcstat.c,v 1.22 2020/03/03 08:56:05 nisimura Exp $ */

/* $NetBSD: ifmcstat.c,v 1.22 2020/03/03 08:56:05 nisimura Exp $ */

/*
* 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.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: ifmcstat.c,v 1.22 2020/03/03 08:56:05 nisimura Exp $");

#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <kvm.h>
#include <nlist.h>
#include <string.h>
#include <limits.h>
#include <util.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <netinet/in.h>
#include <net/if_ether.h>
#include <netinet/in_var.h>
#include <arpa/inet.h>

#include <netdb.h>

static const char *inet6_n2a(void *);
static void print_ether_mcast(u_short);
static void print_inet6_mcast(u_short, const char *);

static const char *
inet6_n2a(void *p)
{
static char buf[NI_MAXHOST];
struct sockaddr_in6 sin6;
const int niflags = NI_NUMERICHOST;

memset(&sin6, 0, sizeof(sin6));
sin6.sin6_family = AF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
memcpy(&sin6.sin6_addr, p, sizeof(sin6.sin6_addr));
inet6_getscopeid(&sin6, INET6_IS_ADDR_LINKLOCAL|
INET6_IS_ADDR_MC_LINKLOCAL);
if (getnameinfo((struct sockaddr *)&sin6, sin6.sin6_len,
buf, sizeof(buf), NULL, 0, niflags) == 0)
return buf;
else
return "(invalid)";
}

static bool
check_inet6_availability(void)
{
size_t dummy;

return sysctlnametomib("net.inet6.multicast", NULL, &dummy) == 0;
}

int
main(void)
{
struct if_nameindex *ifps;
size_t i;
bool inet6_available = check_inet6_availability();

ifps = if_nameindex();
if (ifps == NULL)
errx(1, "failed to obtain list of interfaces");

for (i = 0; ifps[i].if_name != NULL; ++i) {
printf("%s:\n", ifps[i].if_name);
if (inet6_available)
print_inet6_mcast(ifps[i].if_index, ifps[i].if_name);
print_ether_mcast(ifps[i].if_index);
}
if_freenameindex(ifps);

exit(0);
/*NOTREACHED*/
}

static void
print_hwaddr(const uint8_t *hwaddr, size_t len)
{
while (len)
printf("%02x%s", *hwaddr++, --len > 0 ? ":" : "");
}

static void
print_ether_mcast(u_short ifindex)
{
static int ems_oids[4], sdl_oids[3];
size_t i, ems_len, sdl_len;
void *hwaddr;
struct ether_multi_sysctl *ems;

if (ems_oids[0] == 0) {
size_t oidlen = __arraycount(ems_oids);
if (sysctlnametomib("net.ether.multicast", ems_oids, &oidlen) == -1)
errx(1, "net.ether.multicast not found");
if (oidlen != 3)
errx(1, "Wrong OID path for net.ether.multicast");
}

if (sdl_oids[0] == 0) {
size_t oidlen = __arraycount(sdl_oids);
if (sysctlnametomib("net.sdl", sdl_oids, &oidlen) == -1)
errx(1, "net.sdl not found");
if (oidlen != 2)
errx(1, "Wrong OID path for net.sdl");
}

sdl_oids[2] = ifindex;
hwaddr = asysctl(sdl_oids, 3, &sdl_len);

if (sdl_len == 0) {
free(hwaddr);
return;
}
if (hwaddr == NULL) {
warn("failed to read net.sdl");
}

ems_oids[3] = ifindex;
ems = asysctl(ems_oids, 4, &ems_len);
ems_len /= sizeof(*ems);

if (ems == NULL && ems_len != 0) {
warn("failed to read net.ether.multicast");
return;
}

printf("\tenaddr ");
print_hwaddr(hwaddr, sdl_len);
printf(" multicnt %zu\n", ems_len);

for (i = 0; i < ems_len; ++i) {
printf("\t\t");
print_hwaddr(ems[i].enm_addrlo, sdl_len);
printf(" -- ");
print_hwaddr(ems[i].enm_addrhi, sdl_len);
printf(" refcount %d\n", ems[i].enm_refcount);
}
free(ems);
free(hwaddr);
}

static void
print_inet6_mcast(u_short ifindex, const char *ifname)
{
static int mcast_oids[4];
const char *addr;
uint8_t *mcast_addrs, *p, *last_p;
uint32_t refcnt;
size_t len;

if (mcast_oids[0] == 0) {
size_t oidlen = __arraycount(mcast_oids);
if (sysctlnametomib("net.inet6.multicast", mcast_oids,
&oidlen) == -1)
errx(1, "net.inet6.multicast not found");
if (oidlen != 3)
errx(1, "Wrong OID path for net.inet6.multicast");
}

mcast_oids[3] = ifindex;

mcast_addrs = asysctl(mcast_oids, 4, &len);
if (mcast_addrs == NULL && len != 0) {
warn("failed to read net.inet6.multicast");
return;
}
if (len) {
p = mcast_addrs;
last_p = NULL;
while (len >= 2 * sizeof(struct in6_addr) + sizeof(uint32_t)) {
if (last_p == NULL ||
memcmp(p, last_p, sizeof(struct in6_addr)))
printf("\tinet6 %s\n", inet6_n2a(p));
last_p = p;
p += sizeof(struct in6_addr);
addr = inet6_n2a(p);
p += sizeof(struct in6_addr);
memcpy(&refcnt, p, sizeof(refcnt));
p += sizeof(refcnt);
printf("\t\tgroup %s refcount %" PRIu32 "\n", addr,
refcnt);
len -= 2 * sizeof(struct in6_addr) + sizeof(uint32_t);
}
}
free(mcast_addrs);
}