/* $KAME: if.c,v 1.17 2001/01/21 15:27:30 itojun Exp $ */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* Copyright (C) 2011 Hiroki Sato <hrs@FreeBSD.org>
* 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/param.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/ethernet.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#include <unistd.h>
#include <errno.h>
#include <netdb.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include "pathnames.h"
#include "rtadvd.h"
#include "if.h"
#define ROUNDUP(a, size) \
(((a) & ((size)-1)) ? (1 + ((a) | ((size)-1))) : (a))
#define NEXT_SA(ap) \
(ap) = (struct sockaddr *)((caddr_t)(ap) + \
((ap)->sa_len ? ROUNDUP((ap)->sa_len, sizeof(u_long)) : \
sizeof(u_long)))
struct sockaddr_in6 sin6_linklocal_allnodes = {
.sin6_len = sizeof(sin6_linklocal_allnodes),
.sin6_family = AF_INET6,
.sin6_addr = IN6ADDR_LINKLOCAL_ALLNODES_INIT,
};
struct sockaddr_in6 sin6_linklocal_allrouters = {
.sin6_len = sizeof(sin6_linklocal_allrouters),
.sin6_family = AF_INET6,
.sin6_addr = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT,
};
struct sockaddr_in6 sin6_sitelocal_allrouters = {
.sin6_len = sizeof(sin6_sitelocal_allrouters),
.sin6_family = AF_INET6,
.sin6_addr = IN6ADDR_SITELOCAL_ALLROUTERS_INIT,
};
struct sockinfo sock = { .si_fd = -1, .si_name = NULL };
struct sockinfo rtsock = { .si_fd = -1, .si_name = NULL };
struct sockinfo ctrlsock = { .si_fd = -1, .si_name = _PATH_CTRL_SOCK };
char *mcastif;
static void get_rtaddrs(int, struct sockaddr *,
struct sockaddr **);
static struct if_msghdr *get_next_msghdr(struct if_msghdr *,
struct if_msghdr *);
static void
get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info)
{
int i;
for (i = 0; i < RTAX_MAX; i++) {
if (addrs & (1 << i)) {
rti_info[i] = sa;
NEXT_SA(sa);
}
else
rti_info[i] = NULL;
}
}
#define ROUNDUP8(a) (1 + (((a) - 1) | 7))
int
lladdropt_length(struct sockaddr_dl *sdl)
{
switch (sdl->sdl_type) {
case IFT_ETHER:
case IFT_L2VLAN:
case IFT_BRIDGE:
return (ROUNDUP8(ETHER_ADDR_LEN + 2));
default:
return (0);
}
}
void
lladdropt_fill(struct sockaddr_dl *sdl, struct nd_opt_hdr *ndopt)
{
char *addr;
ndopt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; /* fixed */
switch (sdl->sdl_type) {
case IFT_ETHER:
case IFT_L2VLAN:
case IFT_BRIDGE:
ndopt->nd_opt_len = (ROUNDUP8(ETHER_ADDR_LEN + 2)) >> 3;
addr = (char *)(ndopt + 1);
memcpy(addr, LLADDR(sdl), ETHER_ADDR_LEN);
break;
default:
syslog(LOG_ERR, "<%s> unsupported link type(%d)",
__func__, sdl->sdl_type);
exit(1);
}
return;
}
int
rtbuf_len(void)
{
size_t len;
int mib[6] = {CTL_NET, AF_ROUTE, 0, AF_INET6, NET_RT_DUMP, 0};
if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
return (-1);
return (len);
}
#define FILTER_MATCH(type, filter) ((0x1 << type) & filter)
#define SIN6(s) ((struct sockaddr_in6 *)(s))
#define SDL(s) ((struct sockaddr_dl *)(s))
char *
get_next_msg(char *buf, char *lim, int ifindex, size_t *lenp, int filter)
{
struct rt_msghdr *rtm;
struct ifa_msghdr *ifam;
struct sockaddr *sa, *dst, *gw, *ifa, *rti_info[RTAX_MAX];
*lenp = 0;
for (rtm = (struct rt_msghdr *)buf;
rtm < (struct rt_msghdr *)lim;
rtm = (struct rt_msghdr *)(((char *)rtm) + rtm->rtm_msglen)) {
/* just for safety */
if (!rtm->rtm_msglen) {
syslog(LOG_WARNING, "<%s> rtm_msglen is 0 "
"(buf=%p lim=%p rtm=%p)", __func__,
buf, lim, rtm);
break;
}
if (((struct rt_msghdr *)buf)->rtm_version != RTM_VERSION) {
syslog(LOG_WARNING,
"<%s> routing message version mismatch "
"(buf=%p lim=%p rtm=%p)", __func__,
buf, lim, rtm);
continue;
}
if (FILTER_MATCH(rtm->rtm_type, filter) == 0)
continue;
switch (rtm->rtm_type) {
case RTM_GET:
case RTM_ADD:
case RTM_DELETE:
/* address related checks */
sa = (struct sockaddr *)(rtm + 1);
get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
if ((dst = rti_info[RTAX_DST]) == NULL ||
dst->sa_family != AF_INET6)
continue;
if (IN6_IS_ADDR_LINKLOCAL(&SIN6(dst)->sin6_addr) ||
IN6_IS_ADDR_MULTICAST(&SIN6(dst)->sin6_addr))
continue;
if ((gw = rti_info[RTAX_GATEWAY]) == NULL ||
gw->sa_family != AF_LINK)
continue;
if (ifindex && SDL(gw)->sdl_index != ifindex)
continue;
if (rti_info[RTAX_NETMASK] == NULL)
continue;
/* found */
*lenp = rtm->rtm_msglen;
return (char *)rtm;
/* NOTREACHED */
case RTM_NEWADDR:
case RTM_DELADDR:
ifam = (struct ifa_msghdr *)rtm;
/* address related checks */
sa = (struct sockaddr *)(ifam + 1);
get_rtaddrs(ifam->ifam_addrs, sa, rti_info);
if ((ifa = rti_info[RTAX_IFA]) == NULL ||
(ifa->sa_family != AF_INET &&
ifa->sa_family != AF_INET6))
continue;
if (ifa->sa_family == AF_INET6 &&
(IN6_IS_ADDR_LINKLOCAL(&SIN6(ifa)->sin6_addr) ||
IN6_IS_ADDR_MULTICAST(&SIN6(ifa)->sin6_addr)))
continue;
if (ifindex && ifam->ifam_index != ifindex)
continue;
/* found */
*lenp = ifam->ifam_msglen;
return (char *)rtm;
/* NOTREACHED */
case RTM_IFINFO:
case RTM_IFANNOUNCE:
/* found */
*lenp = rtm->rtm_msglen;
return (char *)rtm;
/* NOTREACHED */
}
}
return ((char *)rtm);
}
#undef FILTER_MATCH
struct in6_addr *
get_addr(char *buf)
{
struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
struct sockaddr *sa, *rti_info[RTAX_MAX];
sa = (struct sockaddr *)(rtm + 1);
get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
return (&SIN6(rti_info[RTAX_DST])->sin6_addr);
}
int
get_rtm_ifindex(char *buf)
{
struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
struct sockaddr *sa, *rti_info[RTAX_MAX];
sa = (struct sockaddr *)(rtm + 1);
get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
return (((struct sockaddr_dl *)rti_info[RTAX_GATEWAY])->sdl_index);
}
int
get_prefixlen(char *buf)
{
struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
struct sockaddr *sa, *rti_info[RTAX_MAX];
char *p, *lim;
sa = (struct sockaddr *)(rtm + 1);
get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
sa = rti_info[RTAX_NETMASK];
p = (char *)(&SIN6(sa)->sin6_addr);
lim = (char *)sa + sa->sa_len;
return prefixlen(p, lim);
}
int
prefixlen(unsigned char *p, unsigned char *lim)
{
int masklen;
for (masklen = 0; p < lim; p++) {
switch (*p) {
case 0xff:
masklen += 8;
break;
case 0xfe:
masklen += 7;
break;
case 0xfc:
masklen += 6;
break;
case 0xf8:
masklen += 5;
break;
case 0xf0:
masklen += 4;
break;
case 0xe0:
masklen += 3;
break;
case 0xc0:
masklen += 2;
break;
case 0x80:
masklen += 1;
break;
case 0x00:
break;
default:
return (-1);
}
}
return (masklen);
}
struct ifinfo *
update_persist_ifinfo(struct ifilist_head_t *ifi_head, const char *ifname)
{
struct ifinfo *ifi;
int ifindex;
ifi = NULL;
ifindex = if_nametoindex(ifname);
TAILQ_FOREACH(ifi, ifi_head, ifi_next) {
if (ifindex != 0) {
if (ifindex == ifi->ifi_ifindex)
break;
} else {
if (strncmp(ifname, ifi->ifi_ifname,
sizeof(ifi->ifi_ifname)) == 0)
break;
}
}
if (ifi == NULL) {
/* A new ifinfo element is needed. */
syslog(LOG_DEBUG, "<%s> new entry: %s", __func__,
ifname);
ELM_MALLOC(ifi, exit(1));
ifi->ifi_ifindex = 0;
strlcpy(ifi->ifi_ifname, ifname, sizeof(ifi->ifi_ifname));
ifi->ifi_rainfo = NULL;
ifi->ifi_state = IFI_STATE_UNCONFIGURED;
TAILQ_INSERT_TAIL(ifi_head, ifi, ifi_next);
}
ifi->ifi_persist = 1;
syslog(LOG_DEBUG, "<%s> %s is marked PERSIST", __func__,
ifi->ifi_ifname);
syslog(LOG_DEBUG, "<%s> %s is state = %d", __func__,
ifi->ifi_ifname, ifi->ifi_state);
return (ifi);
}
int
update_ifinfo_nd_flags(struct ifinfo *ifi)
{
struct in6_ndireq nd;
int s;
int error;
if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
syslog(LOG_ERR,
"<%s> socket() failed.", __func__);
return (1);
}
/* ND flags */
memset(&nd, 0, sizeof(nd));
strlcpy(nd.ifname, ifi->ifi_ifname,
sizeof(nd.ifname));
error = ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd);
if (error) {
close(s);
if (errno != EPFNOSUPPORT)
syslog(LOG_ERR, "<%s> ioctl() failed.", __func__);
return (1);
}
ifi->ifi_nd_flags = nd.ndi.flags;
close(s);
return (0);
}
#define MAX_SYSCTL_TRY 5
struct ifinfo *
update_ifinfo(struct ifilist_head_t *ifi_head, int ifindex)
{
struct if_msghdr *ifm;
struct ifinfo *ifi = NULL;
struct sockaddr *sa;
struct sockaddr *rti_info[RTAX_MAX];
char *msg;
size_t len;
char *lim;
int mib[] = { CTL_NET, PF_ROUTE, 0, AF_INET6, NET_RT_IFLIST, 0 };
int error, ntry;
syslog(LOG_DEBUG, "<%s> enter", __func__);
ntry = 0;
do {
/*
* We'll try to get addresses several times in case that
* the number of addresses is unexpectedly increased during
* the two sysctl calls. This should rarely happen.
* Portability note: since FreeBSD does not add margin of
* memory at the first sysctl, the possibility of failure on
* the second sysctl call is a bit higher.
*/
if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) < 0) {
syslog(LOG_ERR,
"<%s> sysctl: NET_RT_IFLIST size get failed",
__func__);
exit(1);
}
if ((msg = malloc(len)) == NULL) {
syslog(LOG_ERR, "<%s> malloc failed", __func__);
exit(1);
}
if (sysctl(mib, nitems(mib), msg, &len, NULL, 0) < 0) {
if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) {
free(msg);
syslog(LOG_ERR,
"<%s> sysctl: NET_RT_IFLIST get failed",
__func__);
exit(1);
}
free(msg);
msg = NULL;
}
} while (msg == NULL);
lim = msg + len;
for (ifm = (struct if_msghdr *)msg;
ifm != NULL && ifm < (struct if_msghdr *)lim;
ifm = get_next_msghdr(ifm,(struct if_msghdr *)lim)) {
int ifi_new;
syslog(LOG_DEBUG, "<%s> ifm = %p, lim = %p, diff = %zu",
__func__, ifm, lim, (char *)lim - (char *)ifm);
if (ifm->ifm_version != RTM_VERSION) {
syslog(LOG_ERR,
"<%s> ifm_vesrion mismatch", __func__);
exit(1);
}
if (ifm->ifm_msglen == 0) {
syslog(LOG_WARNING,
"<%s> ifm_msglen is 0", __func__);
free(msg);
return (NULL);
}
ifi_new = 0;
if (ifm->ifm_type == RTM_IFINFO) {
struct ifreq ifr;
int s;
char ifname[IFNAMSIZ];
syslog(LOG_DEBUG, "<%s> RTM_IFINFO found. "
"ifm_index = %d, ifindex = %d",
__func__, ifm->ifm_index, ifindex);
/* when ifindex is specified */
if (ifindex != UPDATE_IFINFO_ALL &&
ifindex != ifm->ifm_index)
continue;
/* ifname */
if (if_indextoname(ifm->ifm_index, ifname) == NULL) {
syslog(LOG_WARNING,
"<%s> ifname not found (idx=%d)",
__func__, ifm->ifm_index);
continue;
}
/* lookup an entry with the same ifindex */
TAILQ_FOREACH(ifi, ifi_head, ifi_next) {
if (ifm->ifm_index == ifi->ifi_ifindex)
break;
if (strncmp(ifname, ifi->ifi_ifname,
sizeof(ifname)) == 0)
break;
}
if (ifi == NULL) {
syslog(LOG_DEBUG,
"<%s> new entry for idx=%d",
__func__, ifm->ifm_index);
ELM_MALLOC(ifi, exit(1));
ifi->ifi_rainfo = NULL;
ifi->ifi_state = IFI_STATE_UNCONFIGURED;
ifi->ifi_persist = 0;
ifi_new = 1;
}
/* ifindex */
ifi->ifi_ifindex = ifm->ifm_index;
/* ifname */
strlcpy(ifi->ifi_ifname, ifname, IFNAMSIZ);
if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
syslog(LOG_ERR,
"<%s> socket() failed.", __func__);
if (ifi_new)
free(ifi);
continue;
}
/* MTU */
ifi->ifi_phymtu = ifm->ifm_data.ifi_mtu;
if (ifi->ifi_phymtu == 0) {
memset(&ifr, 0, sizeof(ifr));
ifr.ifr_addr.sa_family = AF_INET6;
strlcpy(ifr.ifr_name, ifi->ifi_ifname,
sizeof(ifr.ifr_name));
error = ioctl(s, SIOCGIFMTU, (caddr_t)&ifr);
if (error) {
close(s);
syslog(LOG_ERR,
"<%s> ioctl() failed.",
__func__);
if (ifi_new)
free(ifi);
continue;
}
ifi->ifi_phymtu = ifr.ifr_mtu;
if (ifi->ifi_phymtu == 0) {
syslog(LOG_WARNING,
"<%s> no interface mtu info"
" on %s. %d will be used.",
__func__, ifi->ifi_ifname,
IPV6_MMTU);
ifi->ifi_phymtu = IPV6_MMTU;
}
}
close(s);
/* ND flags */
error = update_ifinfo_nd_flags(ifi);
if (error) {
if (ifi_new)
free(ifi);
continue;
}
/* SDL */
sa = (struct sockaddr *)(ifm + 1);
get_rtaddrs(ifm->ifm_addrs, sa, rti_info);
if ((sa = rti_info[RTAX_IFP]) != NULL) {
if (sa->sa_family == AF_LINK) {
memcpy(&ifi->ifi_sdl,
(struct sockaddr_dl *)sa,
sizeof(ifi->ifi_sdl));
}
} else
memset(&ifi->ifi_sdl, 0,
sizeof(ifi->ifi_sdl));
/* flags */
ifi->ifi_flags = ifm->ifm_flags;
/* type */
ifi->ifi_type = ifm->ifm_type;
} else {
syslog(LOG_ERR,
"out of sync parsing NET_RT_IFLIST\n"
"expected %d, got %d\n msglen = %d\n",
RTM_IFINFO, ifm->ifm_type, ifm->ifm_msglen);
exit(1);
}
if (ifi_new) {
syslog(LOG_DEBUG,
"<%s> adding %s(idx=%d) to ifilist",
__func__, ifi->ifi_ifname, ifi->ifi_ifindex);
TAILQ_INSERT_TAIL(ifi_head, ifi, ifi_next);
}
}
free(msg);
if (mcastif != NULL) {
error = sock_mc_rr_update(&sock, mcastif);
if (error)
exit(1);
}
return (ifi);
}
static struct if_msghdr *
get_next_msghdr(struct if_msghdr *ifm, struct if_msghdr *lim)
{
struct ifa_msghdr *ifam;
for (ifam = (struct ifa_msghdr *)((char *)ifm + ifm->ifm_msglen);
ifam < (struct ifa_msghdr *)lim;
ifam = (struct ifa_msghdr *)((char *)ifam + ifam->ifam_msglen)) {
if (!ifam->ifam_msglen) {
syslog(LOG_WARNING,
"<%s> ifa_msglen is 0", __func__);
return (NULL);
}
if (ifam->ifam_type != RTM_NEWADDR)
break;
}
return ((struct if_msghdr *)ifam);
}
int
getinet6sysctl(int code)
{
int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, 0 };
int value;
size_t size;
mib[3] = code;
size = sizeof(value);
if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), &value, &size, NULL, 0)
< 0) {
syslog(LOG_ERR, "<%s>: failed to get ip6 sysctl(%d): %s",
__func__, code,
strerror(errno));
return (-1);
}
else
return (value);
}
int
sock_mc_join(struct sockinfo *s, int ifindex)
{
struct ipv6_mreq mreq;
char ifname[IFNAMSIZ];
syslog(LOG_DEBUG, "<%s> enter", __func__);
if (ifindex == 0)
return (1);
/*
* join all routers multicast address on each advertising
* interface.
*/
memset(&mreq, 0, sizeof(mreq));
/* XXX */
memcpy(&mreq.ipv6mr_multiaddr.s6_addr,
&sin6_linklocal_allrouters.sin6_addr,
sizeof(mreq.ipv6mr_multiaddr.s6_addr));
mreq.ipv6mr_interface = ifindex;
if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
sizeof(mreq)) < 0) {
syslog(LOG_ERR,
"<%s> IPV6_JOIN_GROUP(link) on %s: %s",
__func__, if_indextoname(ifindex, ifname),
strerror(errno));
return (1);
}
syslog(LOG_DEBUG,
"<%s> %s: join link-local all-routers MC group",
__func__, if_indextoname(ifindex, ifname));
return (0);
}
int
sock_mc_leave(struct sockinfo *s, int ifindex)
{
struct ipv6_mreq mreq;
char ifname[IFNAMSIZ];
syslog(LOG_DEBUG, "<%s> enter", __func__);
if (ifindex == 0)
return (1);
/*
* join all routers multicast address on each advertising
* interface.
*/
memset(&mreq, 0, sizeof(mreq));
/* XXX */
memcpy(&mreq.ipv6mr_multiaddr.s6_addr,
&sin6_linklocal_allrouters.sin6_addr,
sizeof(mreq.ipv6mr_multiaddr.s6_addr));
mreq.ipv6mr_interface = ifindex;
if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &mreq,
sizeof(mreq)) < 0) {
syslog(LOG_ERR,
"<%s> IPV6_JOIN_LEAVE(link) on %s: %s",
__func__, if_indextoname(ifindex, ifname),
strerror(errno));
return (1);
}
syslog(LOG_DEBUG,
"<%s> %s: leave link-local all-routers MC group",
__func__, if_indextoname(ifindex, ifname));
return (0);
}
int
sock_mc_rr_update(struct sockinfo *s, char *mif)
{
struct ipv6_mreq mreq;
syslog(LOG_DEBUG, "<%s> enter", __func__);
if (mif == NULL)
return (1);
/*
* When attending router renumbering, join all-routers site-local
* multicast group.
*/
/* XXX */
memcpy(&mreq.ipv6mr_multiaddr.s6_addr,
&sin6_sitelocal_allrouters.sin6_addr,
sizeof(mreq.ipv6mr_multiaddr.s6_addr));
if ((mreq.ipv6mr_interface = if_nametoindex(mif)) == 0) {
syslog(LOG_ERR,
"<%s> invalid interface: %s",
__func__, mif);
return (1);
}
if (setsockopt(s->si_fd, IPPROTO_IPV6, IPV6_JOIN_GROUP,
&mreq, sizeof(mreq)) < 0) {
syslog(LOG_ERR,
"<%s> IPV6_JOIN_GROUP(site) on %s: %s",
__func__, mif, strerror(errno));
return (1);
}
syslog(LOG_DEBUG,
"<%s> %s: join site-local all-routers MC group",
__func__, mif);
return (0);
}
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