freebsd-skq/sbin/ifconfig/af_nd6.c
Hiroki Sato a283298ce3 Improve flexibility of receiving Router Advertisement and
automatic link-local address configuration:

- Convert a sysctl net.inet6.ip6.accept_rtadv to one for the
  default value of a per-IF flag ND6_IFF_ACCEPT_RTADV, not a
  global knob.  The default value of the sysctl is 0.

- Add a new per-IF flag ND6_IFF_AUTO_LINKLOCAL and convert a
  sysctl net.inet6.ip6.auto_linklocal to one for its default
  value.  The default value of the sysctl is 1.

- Make ND6_IFF_IFDISABLED more robust.  It can be used to disable
  IPv6 functionality of an interface now.

- Receiving RA is allowed if ip6_forwarding==0 *and*
  ND6_IFF_ACCEPT_RTADV is set on that interface.  The former
  condition will be revisited later to support a "host + router" box
  like IPv6 CPE router.  The current behavior is compatible with
  the older releases of FreeBSD.

- The ifconfig(8) now supports these ND6 flags as well as "nud",
  "prefer_source", and "disabled" in ndp(8).  The ndp(8) now
  supports "auto_linklocal".

Discussed with:	bz and jinmei
Reviewed by:	bz
MFC after:	3 days
2009-09-12 22:08:20 +00:00

252 lines
5.9 KiB
C

/*
* Copyright (c) 2009 Hiroki Sato. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
#ifndef lint
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/route.h>
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ifaddrs.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <net/if_var.h>
#include <netinet/in_var.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <netinet6/nd6.h>
#include "ifconfig.h"
#define MAX_SYSCTL_TRY 5
static struct nd6_opt_list {
const char *label;
u_int mask;
} nd6_opts[] = {
{ "IFDISABLED", ND6_IFF_IFDISABLED, },
{ "PERFORMNUD", ND6_IFF_PERFORMNUD, },
{ "ACCEPT_RTADV", ND6_IFF_ACCEPT_RTADV, },
{ "PREFER_SOURCE", ND6_IFF_PREFER_SOURCE, },
{ "AUTO_LINKLOCAL", ND6_IFF_AUTO_LINKLOCAL, },
};
static int isnd6defif(int);
void setnd6flags(const char *, int, int, const struct afswtch *);
void setnd6defif(const char *, int, int, const struct afswtch *);
void
setnd6flags(const char *dummyaddr __unused,
int d, int s,
const struct afswtch *afp)
{
struct in6_ndireq nd;
int error;
memset(&nd, 0, sizeof(nd));
strncpy(nd.ifname, ifr.ifr_name, sizeof(nd.ifname));
error = ioctl(s, SIOCGIFINFO_IN6, &nd);
if (error) {
warn("ioctl(SIOCGIFINFO_IN6)");
return;
}
if (d < 0)
nd.ndi.flags &= ~(-d);
else
nd.ndi.flags |= d;
error = ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd);
if (error)
warn("ioctl(SIOCSIFINFO_IN6)");
}
void
setnd6defif(const char *dummyaddr __unused,
int d, int s,
const struct afswtch *afp)
{
struct in6_ndifreq ndifreq;
int ifindex;
int error;
memset(&ndifreq, 0, sizeof(ndifreq));
strncpy(ndifreq.ifname, ifr.ifr_name, sizeof(ndifreq.ifname));
if (d < 0) {
if (isnd6defif(s)) {
/* ifindex = 0 means to remove default if */
ifindex = 0;
} else
return;
} else if ((ifindex = if_nametoindex(ndifreq.ifname)) == 0) {
warn("if_nametoindex(%s)", ndifreq.ifname);
return;
}
ndifreq.ifindex = ifindex;
error = ioctl(s, SIOCSDEFIFACE_IN6, (caddr_t)&ndifreq);
if (error)
warn("ioctl(SIOCSDEFIFACE_IN6)");
}
static int
isnd6defif(int s)
{
struct in6_ndifreq ndifreq;
unsigned int ifindex;
int error;
memset(&ndifreq, 0, sizeof(ndifreq));
strncpy(ndifreq.ifname, ifr.ifr_name, sizeof(ndifreq.ifname));
ifindex = if_nametoindex(ndifreq.ifname);
error = ioctl(s, SIOCGDEFIFACE_IN6, (caddr_t)&ndifreq);
if (error) {
warn("ioctl(SIOCGDEFIFACE_IN6)");
return (error);
}
return (ndifreq.ifindex == ifindex);
}
static void
nd6_status(int s)
{
struct in6_ndireq nd;
struct rt_msghdr *rtm;
size_t needed;
char *buf, *next;
int mib[6], ntry;
int s6;
int i, error;
int isinet6, isdefif;
int nopts;
/* Check if the interface has at least one IPv6 address. */
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = AF_INET6;
mib[4] = NET_RT_IFLIST;
mib[5] = if_nametoindex(ifr.ifr_name);
/* Try to prevent a race between two sysctls. */
ntry = 0;
do {
error = sysctl(mib, 6, NULL, &needed, NULL, 0);
if (error) {
warn("sysctl(NET_RT_IFLIST)/estimate");
return;
}
buf = malloc(needed);
if (buf == NULL) {
warn("malloc for sysctl(NET_RT_IFLIST) failed");
return;
}
if ((error = sysctl(mib, 6, buf, &needed, NULL, 0)) < 0) {
if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) {
warn("sysctl(NET_RT_IFLIST)/get");
free(buf);
return;
}
free(buf);
buf = NULL;
}
} while (buf == NULL);
isinet6 = 0;
for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)next;
if (rtm->rtm_version != RTM_VERSION)
continue;
if (rtm->rtm_type == RTM_NEWADDR) {
isinet6 = 1;
break;
}
}
free(buf);
if (!isinet6)
return;
memset(&nd, 0, sizeof(nd));
strncpy(nd.ifname, ifr.ifr_name, sizeof(nd.ifname));
if ((s6 = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
warn("socket(AF_INET6, SOCK_DGRAM)");
return;
}
error = ioctl(s6, SIOCGIFINFO_IN6, &nd);
if (error) {
warn("ioctl(SIOCGIFINFO_IN6)");
close(s6);
return;
}
isdefif = isnd6defif(s6);
close(s6);
if (nd.ndi.flags == 0 && !isdefif)
return;
nopts = 0;
printf("\tnd6 options=%d<", nd.ndi.flags);
for (i=0; i < sizeof(nd6_opts)/sizeof(nd6_opts[0]); i++) {
if (nd.ndi.flags & nd6_opts[i].mask) {
if (nopts++)
printf(",");
printf("%s", nd6_opts[i].label);
}
}
if (isdefif) {
if (nopts)
printf(",");
printf("DEFAULTIF");
}
printf(">\n");
}
static struct afswtch af_nd6 = {
.af_name = "nd6",
.af_af = AF_LOCAL,
.af_other_status= nd6_status,
};
static __constructor void
nd6_ctor(void)
{
af_register(&af_nd6);
}