freebsd-skq/usr.sbin/rtsold/rtsold.c
Pedro F. Giffuni 8a16b7a18f General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

928 lines
20 KiB
C

/* $KAME: rtsold.c,v 1.67 2003/05/17 18:16:15 itojun Exp $ */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <netinet/in.h>
#include <netinet/icmp6.h>
#include <netinet/in_var.h>
#include <arpa/inet.h>
#include <netinet6/nd6.h>
#include <signal.h>
#include <unistd.h>
#include <syslog.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <errno.h>
#include <err.h>
#include <stdarg.h>
#include <ifaddrs.h>
#include <poll.h>
#include "rtsold.h"
#define RTSOL_DUMPFILE "/var/run/rtsold.dump";
#define RTSOL_PIDFILE "/var/run/rtsold.pid";
struct timespec tm_max;
static int log_upto = 999;
static int fflag = 0;
int Fflag = 0; /* force setting sysctl parameters */
int aflag = 0;
int dflag = 0;
int uflag = 0;
const char *otherconf_script;
const char *resolvconf_script = "/sbin/resolvconf";
/* protocol constants */
#define MAX_RTR_SOLICITATION_DELAY 1 /* second */
#define RTR_SOLICITATION_INTERVAL 4 /* seconds */
#define MAX_RTR_SOLICITATIONS 3 /* times */
/*
* implementation dependent constants in seconds
* XXX: should be configurable
*/
#define PROBE_INTERVAL 60
/* static variables and functions */
static int mobile_node = 0;
static const char *pidfilename = RTSOL_PIDFILE;
#ifndef SMALL
static int do_dump;
static const char *dumpfilename = RTSOL_DUMPFILE;
#endif
#if 0
static int ifreconfig(char *);
#endif
static int make_packet(struct ifinfo *);
static struct timespec *rtsol_check_timer(void);
#ifndef SMALL
static void rtsold_set_dump_file(int);
#endif
static void usage(void);
int
main(int argc, char **argv)
{
int s, ch, once = 0;
struct timespec *timeout;
const char *opts;
struct pollfd set[2];
int rtsock;
char *argv0;
#ifndef SMALL
/* rtsold */
opts = "adDfFm1O:p:R:u";
#else
/* rtsol */
opts = "adDFO:R:u";
fflag = 1;
once = 1;
#endif
argv0 = argv[0];
while ((ch = getopt(argc, argv, opts)) != -1) {
switch (ch) {
case 'a':
aflag = 1;
break;
case 'd':
dflag += 1;
break;
case 'D':
dflag += 2;
break;
case 'f':
fflag = 1;
break;
case 'F':
Fflag = 1;
break;
case 'm':
mobile_node = 1;
break;
case '1':
once = 1;
break;
case 'O':
otherconf_script = optarg;
break;
case 'p':
pidfilename = optarg;
break;
case 'R':
resolvconf_script = optarg;
break;
case 'u':
uflag = 1;
break;
default:
usage();
exit(1);
}
}
argc -= optind;
argv += optind;
if ((!aflag && argc == 0) || (aflag && argc != 0)) {
usage();
exit(1);
}
/* Generate maximum time in timespec. */
tm_max.tv_sec = (-1) & ~((time_t)1 << ((sizeof(tm_max.tv_sec) * 8) - 1));
tm_max.tv_nsec = (-1) & ~((long)1 << ((sizeof(tm_max.tv_nsec) * 8) - 1));
/* set log level */
if (dflag > 1)
log_upto = LOG_DEBUG;
else if (dflag > 0)
log_upto = LOG_INFO;
else
log_upto = LOG_NOTICE;
if (!fflag) {
char *ident;
ident = strrchr(argv0, '/');
if (!ident)
ident = argv0;
else
ident++;
openlog(ident, LOG_NDELAY|LOG_PID, LOG_DAEMON);
if (log_upto >= 0)
setlogmask(LOG_UPTO(log_upto));
}
if (otherconf_script && *otherconf_script != '/') {
errx(1, "configuration script (%s) must be an absolute path",
otherconf_script);
}
if (resolvconf_script && *resolvconf_script != '/') {
errx(1, "configuration script (%s) must be an absolute path",
resolvconf_script);
}
if (pidfilename && *pidfilename != '/') {
errx(1, "pid filename (%s) must be an absolute path",
pidfilename);
}
#if (__FreeBSD_version < 900000)
if (Fflag) {
setinet6sysctl(IPV6CTL_FORWARDING, 0);
} else {
/* warn if forwarding is up */
if (getinet6sysctl(IPV6CTL_FORWARDING))
warnx("kernel is configured as a router, not a host");
}
#endif
#ifndef SMALL
/* initialization to dump internal status to a file */
signal(SIGUSR1, rtsold_set_dump_file);
#endif
if (!fflag)
daemon(0, 0); /* act as a daemon */
/*
* Open a socket for sending RS and receiving RA.
* This should be done before calling ifinit(), since the function
* uses the socket.
*/
if ((s = sockopen()) < 0) {
warnmsg(LOG_ERR, __func__, "failed to open a socket");
exit(1);
}
set[0].fd = s;
set[0].events = POLLIN;
set[1].fd = -1;
if ((rtsock = rtsock_open()) < 0) {
warnmsg(LOG_ERR, __func__, "failed to open a socket");
exit(1);
}
set[1].fd = rtsock;
set[1].events = POLLIN;
/* configuration per interface */
if (ifinit()) {
warnmsg(LOG_ERR, __func__,
"failed to initialize interfaces");
exit(1);
}
if (aflag)
argv = autoifprobe();
while (argv && *argv) {
if (ifconfig(*argv)) {
warnmsg(LOG_ERR, __func__,
"failed to initialize %s", *argv);
exit(1);
}
argv++;
}
/* setup for probing default routers */
if (probe_init()) {
warnmsg(LOG_ERR, __func__,
"failed to setup for probing routers");
exit(1);
/*NOTREACHED*/
}
/* dump the current pid */
if (!once) {
pid_t pid = getpid();
FILE *fp;
if ((fp = fopen(pidfilename, "w")) == NULL)
warnmsg(LOG_ERR, __func__,
"failed to open a pid log file(%s): %s",
pidfilename, strerror(errno));
else {
fprintf(fp, "%d\n", pid);
fclose(fp);
}
}
while (1) { /* main loop */
int e;
#ifndef SMALL
if (do_dump) { /* SIGUSR1 */
do_dump = 0;
rtsold_dump_file(dumpfilename);
}
#endif
timeout = rtsol_check_timer();
if (once) {
struct ifinfo *ifi;
/* if we have no timeout, we are done (or failed) */
if (timeout == NULL)
break;
/* if all interfaces have got RA packet, we are done */
TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
if (ifi->state != IFS_DOWN && ifi->racnt == 0)
break;
}
if (ifi == NULL)
break;
}
e = poll(set, 2, timeout ? (timeout->tv_sec * 1000 + timeout->tv_nsec / 1000 / 1000) : INFTIM);
if (e < 1) {
if (e < 0 && errno != EINTR) {
warnmsg(LOG_ERR, __func__, "select: %s",
strerror(errno));
}
continue;
}
/* packet reception */
if (set[1].revents & POLLIN)
rtsock_input(rtsock);
if (set[0].revents & POLLIN)
rtsol_input(s);
}
/* NOTREACHED */
return (0);
}
int
ifconfig(char *ifname)
{
struct ifinfo *ifi;
struct sockaddr_dl *sdl;
int flags;
if ((sdl = if_nametosdl(ifname)) == NULL) {
warnmsg(LOG_ERR, __func__,
"failed to get link layer information for %s", ifname);
return (-1);
}
if (find_ifinfo(sdl->sdl_index)) {
warnmsg(LOG_ERR, __func__,
"interface %s was already configured", ifname);
free(sdl);
return (-1);
}
if (Fflag) {
struct in6_ndireq nd;
int s;
if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
warnmsg(LOG_ERR, __func__, "socket() failed.");
return (-1);
}
memset(&nd, 0, sizeof(nd));
strlcpy(nd.ifname, ifname, sizeof(nd.ifname));
if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
warnmsg(LOG_ERR, __func__,
"cannot get accept_rtadv flag");
close(s);
return (-1);
}
nd.ndi.flags |= ND6_IFF_ACCEPT_RTADV;
if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd) < 0) {
warnmsg(LOG_ERR, __func__,
"cannot set accept_rtadv flag");
close(s);
return (-1);
}
close(s);
}
if ((ifi = malloc(sizeof(*ifi))) == NULL) {
warnmsg(LOG_ERR, __func__, "memory allocation failed");
free(sdl);
return (-1);
}
memset(ifi, 0, sizeof(*ifi));
ifi->sdl = sdl;
ifi->ifi_rdnss = IFI_DNSOPT_STATE_NOINFO;
ifi->ifi_dnssl = IFI_DNSOPT_STATE_NOINFO;
TAILQ_INIT(&ifi->ifi_rainfo);
strlcpy(ifi->ifname, ifname, sizeof(ifi->ifname));
/* construct a router solicitation message */
if (make_packet(ifi))
goto bad;
/* set link ID of this interface. */
#ifdef HAVE_SCOPELIB
if (inet_zoneid(AF_INET6, 2, ifname, &ifi->linkid))
goto bad;
#else
/* XXX: assume interface IDs as link IDs */
ifi->linkid = ifi->sdl->sdl_index;
#endif
/*
* check if the interface is available.
* also check if SIOCGIFMEDIA ioctl is OK on the interface.
*/
ifi->mediareqok = 1;
ifi->active = interface_status(ifi);
if (!ifi->mediareqok) {
/*
* probe routers periodically even if the link status
* does not change.
*/
ifi->probeinterval = PROBE_INTERVAL;
}
/* activate interface: interface_up returns 0 on success */
flags = interface_up(ifi->ifname);
if (flags == 0)
ifi->state = IFS_DELAY;
else if (flags == IFS_TENTATIVE)
ifi->state = IFS_TENTATIVE;
else
ifi->state = IFS_DOWN;
rtsol_timer_update(ifi);
TAILQ_INSERT_TAIL(&ifinfo_head, ifi, ifi_next);
return (0);
bad:
free(ifi->sdl);
free(ifi);
return (-1);
}
void
iflist_init(void)
{
struct ifinfo *ifi;
while ((ifi = TAILQ_FIRST(&ifinfo_head)) != NULL) {
TAILQ_REMOVE(&ifinfo_head, ifi, ifi_next);
if (ifi->sdl != NULL)
free(ifi->sdl);
if (ifi->rs_data != NULL)
free(ifi->rs_data);
free(ifi);
}
}
#if 0
static int
ifreconfig(char *ifname)
{
struct ifinfo *ifi, *prev;
int rv;
prev = NULL;
TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
if (strncmp(ifi->ifname, ifname, sizeof(ifi->ifname)) == 0)
break;
prev = ifi;
}
prev->next = ifi->next;
rv = ifconfig(ifname);
/* reclaim it after ifconfig() in case ifname is pointer inside ifi */
if (ifi->rs_data)
free(ifi->rs_data);
free(ifi->sdl);
free(ifi);
return (rv);
}
#endif
struct rainfo *
find_rainfo(struct ifinfo *ifi, struct sockaddr_in6 *sin6)
{
struct rainfo *rai;
TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next)
if (memcmp(&rai->rai_saddr.sin6_addr, &sin6->sin6_addr,
sizeof(rai->rai_saddr.sin6_addr)) == 0)
return (rai);
return (NULL);
}
struct ifinfo *
find_ifinfo(int ifindex)
{
struct ifinfo *ifi;
TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
if (ifi->sdl->sdl_index == ifindex)
return (ifi);
}
return (NULL);
}
static int
make_packet(struct ifinfo *ifi)
{
size_t packlen = sizeof(struct nd_router_solicit), lladdroptlen = 0;
struct nd_router_solicit *rs;
char *buf;
if ((lladdroptlen = lladdropt_length(ifi->sdl)) == 0) {
warnmsg(LOG_INFO, __func__,
"link-layer address option has null length"
" on %s. Treat as not included.", ifi->ifname);
}
packlen += lladdroptlen;
ifi->rs_datalen = packlen;
/* allocate buffer */
if ((buf = malloc(packlen)) == NULL) {
warnmsg(LOG_ERR, __func__,
"memory allocation failed for %s", ifi->ifname);
return (-1);
}
ifi->rs_data = buf;
/* fill in the message */
rs = (struct nd_router_solicit *)buf;
rs->nd_rs_type = ND_ROUTER_SOLICIT;
rs->nd_rs_code = 0;
rs->nd_rs_cksum = 0;
rs->nd_rs_reserved = 0;
buf += sizeof(*rs);
/* fill in source link-layer address option */
if (lladdroptlen)
lladdropt_fill(ifi->sdl, (struct nd_opt_hdr *)buf);
return (0);
}
static struct timespec *
rtsol_check_timer(void)
{
static struct timespec returnval;
struct timespec now, rtsol_timer;
struct ifinfo *ifi;
struct rainfo *rai;
struct ra_opt *rao, *raotmp;
int flags;
clock_gettime(CLOCK_MONOTONIC_FAST, &now);
rtsol_timer = tm_max;
TAILQ_FOREACH(ifi, &ifinfo_head, ifi_next) {
if (TS_CMP(&ifi->expire, &now, <=)) {
warnmsg(LOG_DEBUG, __func__, "timer expiration on %s, "
"state = %d", ifi->ifname, ifi->state);
while((rai = TAILQ_FIRST(&ifi->ifi_rainfo)) != NULL) {
/* Remove all RA options. */
TAILQ_REMOVE(&ifi->ifi_rainfo, rai, rai_next);
while ((rao = TAILQ_FIRST(&rai->rai_ra_opt)) !=
NULL) {
TAILQ_REMOVE(&rai->rai_ra_opt, rao,
rao_next);
if (rao->rao_msg != NULL)
free(rao->rao_msg);
free(rao);
}
free(rai);
}
switch (ifi->state) {
case IFS_DOWN:
case IFS_TENTATIVE:
/* interface_up returns 0 on success */
flags = interface_up(ifi->ifname);
if (flags == 0)
ifi->state = IFS_DELAY;
else if (flags == IFS_TENTATIVE)
ifi->state = IFS_TENTATIVE;
else
ifi->state = IFS_DOWN;
break;
case IFS_IDLE:
{
int oldstatus = ifi->active;
int probe = 0;
ifi->active = interface_status(ifi);
if (oldstatus != ifi->active) {
warnmsg(LOG_DEBUG, __func__,
"%s status is changed"
" from %d to %d",
ifi->ifname,
oldstatus, ifi->active);
probe = 1;
ifi->state = IFS_DELAY;
} else if (ifi->probeinterval &&
(ifi->probetimer -=
ifi->timer.tv_sec) <= 0) {
/* probe timer expired */
ifi->probetimer =
ifi->probeinterval;
probe = 1;
ifi->state = IFS_PROBE;
}
/*
* If we need a probe, clear the previous
* status wrt the "other" configuration.
*/
if (probe)
ifi->otherconfig = 0;
if (probe && mobile_node)
defrouter_probe(ifi);
break;
}
case IFS_DELAY:
ifi->state = IFS_PROBE;
sendpacket(ifi);
break;
case IFS_PROBE:
if (ifi->probes < MAX_RTR_SOLICITATIONS)
sendpacket(ifi);
else {
warnmsg(LOG_INFO, __func__,
"No answer after sending %d RSs",
ifi->probes);
ifi->probes = 0;
ifi->state = IFS_IDLE;
}
break;
}
rtsol_timer_update(ifi);
} else {
/* Expiration check for RA options. */
int expire = 0;
TAILQ_FOREACH(rai, &ifi->ifi_rainfo, rai_next) {
TAILQ_FOREACH_SAFE(rao, &rai->rai_ra_opt,
rao_next, raotmp) {
warnmsg(LOG_DEBUG, __func__,
"RA expiration timer: "
"type=%d, msg=%s, expire=%s",
rao->rao_type, (char *)rao->rao_msg,
sec2str(&rao->rao_expire));
if (TS_CMP(&now, &rao->rao_expire,
>=)) {
warnmsg(LOG_DEBUG, __func__,
"RA expiration timer: "
"expired.");
TAILQ_REMOVE(&rai->rai_ra_opt,
rao, rao_next);
if (rao->rao_msg != NULL)
free(rao->rao_msg);
free(rao);
expire = 1;
}
}
}
if (expire)
ra_opt_handler(ifi);
}
if (TS_CMP(&ifi->expire, &rtsol_timer, <))
rtsol_timer = ifi->expire;
}
if (TS_CMP(&rtsol_timer, &tm_max, ==)) {
warnmsg(LOG_DEBUG, __func__, "there is no timer");
return (NULL);
} else if (TS_CMP(&rtsol_timer, &now, <))
/* this may occur when the interval is too small */
returnval.tv_sec = returnval.tv_nsec = 0;
else
TS_SUB(&rtsol_timer, &now, &returnval);
now.tv_sec += returnval.tv_sec;
now.tv_nsec += returnval.tv_nsec;
warnmsg(LOG_DEBUG, __func__, "New timer is %s",
sec2str(&now));
return (&returnval);
}
void
rtsol_timer_update(struct ifinfo *ifi)
{
#define MILLION 1000000
#define DADRETRY 10 /* XXX: adhoc */
long interval;
struct timespec now;
bzero(&ifi->timer, sizeof(ifi->timer));
switch (ifi->state) {
case IFS_DOWN:
case IFS_TENTATIVE:
if (++ifi->dadcount > DADRETRY) {
ifi->dadcount = 0;
ifi->timer.tv_sec = PROBE_INTERVAL;
} else
ifi->timer.tv_sec = 1;
break;
case IFS_IDLE:
if (mobile_node) {
/* XXX should be configurable */
ifi->timer.tv_sec = 3;
}
else
ifi->timer = tm_max; /* stop timer(valid?) */
break;
case IFS_DELAY:
interval = arc4random_uniform(MAX_RTR_SOLICITATION_DELAY * MILLION);
ifi->timer.tv_sec = interval / MILLION;
ifi->timer.tv_nsec = (interval % MILLION) * 1000;
break;
case IFS_PROBE:
if (ifi->probes < MAX_RTR_SOLICITATIONS)
ifi->timer.tv_sec = RTR_SOLICITATION_INTERVAL;
else {
/*
* After sending MAX_RTR_SOLICITATIONS solicitations,
* we're just waiting for possible replies; there
* will be no more solicitation. Thus, we change
* the timer value to MAX_RTR_SOLICITATION_DELAY based
* on RFC 2461, Section 6.3.7.
*/
ifi->timer.tv_sec = MAX_RTR_SOLICITATION_DELAY;
}
break;
default:
warnmsg(LOG_ERR, __func__,
"illegal interface state(%d) on %s",
ifi->state, ifi->ifname);
return;
}
/* reset the timer */
if (TS_CMP(&ifi->timer, &tm_max, ==)) {
ifi->expire = tm_max;
warnmsg(LOG_DEBUG, __func__,
"stop timer for %s", ifi->ifname);
} else {
clock_gettime(CLOCK_MONOTONIC_FAST, &now);
TS_ADD(&now, &ifi->timer, &ifi->expire);
now.tv_sec += ifi->timer.tv_sec;
now.tv_nsec += ifi->timer.tv_nsec;
warnmsg(LOG_DEBUG, __func__, "set timer for %s to %s",
ifi->ifname, sec2str(&now));
}
#undef MILLION
}
/* timer related utility functions */
#define MILLION 1000000
#ifndef SMALL
static void
rtsold_set_dump_file(int sig __unused)
{
do_dump = 1;
}
#endif
static void
usage(void)
{
#ifndef SMALL
fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
"[-p pidfile] [-R script-name] interface ...\n");
fprintf(stderr, "usage: rtsold [-dDfFm1] [-O script-name] "
"[-p pidfile] [-R script-name] -a\n");
#else
fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
"[-p pidfile] [-R script-name] interface ...\n");
fprintf(stderr, "usage: rtsol [-dDF] [-O script-name] "
"[-p pidfile] [-R script-name] -a\n");
#endif
}
void
warnmsg(int priority, const char *func, const char *msg, ...)
{
va_list ap;
char buf[BUFSIZ];
va_start(ap, msg);
if (fflag) {
if (priority <= log_upto) {
(void)vfprintf(stderr, msg, ap);
(void)fprintf(stderr, "\n");
}
} else {
snprintf(buf, sizeof(buf), "<%s> %s", func, msg);
msg = buf;
vsyslog(priority, msg, ap);
}
va_end(ap);
}
/*
* return a list of interfaces which is suitable to sending an RS.
*/
char **
autoifprobe(void)
{
static char **argv = NULL;
static int n = 0;
char **a;
int s = 0, i, found;
struct ifaddrs *ifap, *ifa;
struct in6_ndireq nd;
/* initialize */
while (n--)
free(argv[n]);
if (argv) {
free(argv);
argv = NULL;
}
n = 0;
if (getifaddrs(&ifap) != 0)
return (NULL);
if (!Fflag && (s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
warnmsg(LOG_ERR, __func__, "socket");
exit(1);
}
/* find an ethernet */
for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
if ((ifa->ifa_flags & IFF_UP) == 0)
continue;
if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
continue;
if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
continue;
if ((ifa->ifa_flags & IFF_MULTICAST) == 0)
continue;
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
found = 0;
for (i = 0; i < n; i++) {
if (strcmp(argv[i], ifa->ifa_name) == 0) {
found++;
break;
}
}
if (found)
continue;
/*
* Skip the interfaces which IPv6 and/or accepting RA
* is disabled.
*/
if (!Fflag) {
memset(&nd, 0, sizeof(nd));
strlcpy(nd.ifname, ifa->ifa_name, sizeof(nd.ifname));
if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
warnmsg(LOG_ERR, __func__,
"ioctl(SIOCGIFINFO_IN6)");
exit(1);
}
if ((nd.ndi.flags & ND6_IFF_IFDISABLED))
continue;
if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV))
continue;
}
/* if we find multiple candidates, just warn. */
if (n != 0 && dflag > 1)
warnmsg(LOG_WARNING, __func__,
"multiple interfaces found");
a = realloc(argv, (n + 1) * sizeof(char *));
if (a == NULL) {
warnmsg(LOG_ERR, __func__, "realloc");
exit(1);
}
argv = a;
argv[n] = strdup(ifa->ifa_name);
if (!argv[n]) {
warnmsg(LOG_ERR, __func__, "malloc");
exit(1);
}
n++;
}
if (n) {
a = realloc(argv, (n + 1) * sizeof(char *));
if (a == NULL) {
warnmsg(LOG_ERR, __func__, "realloc");
exit(1);
}
argv = a;
argv[n] = NULL;
if (dflag > 0) {
for (i = 0; i < n; i++)
warnmsg(LOG_WARNING, __func__, "probing %s",
argv[i]);
}
}
if (!Fflag)
close(s);
freeifaddrs(ifap);
return (argv);
}