- Improve interface list handling. The rtadvd(8) now supports dynamically-

  added/removed interfaces in a more consistent manner and reloading the
  configuration file.

- Implement burst unsolicited RA sending into the internal RA timer framework
  when AdvSendAdvertisements and/or configuration entries are changed as
  described in RFC 4861 6.2.4.  This fixes issues that make termination of the
  rtadvd(8) daemon take very long time.

  An interface now has three internal states, UNCONFIGURED, TRANSITIVE, or
  CONFIGURED, and the burst unsolicited sending happens in TRANSITIVE.
  See rtadvd.h for the details.

- rtadvd(8) now accepts non-existent interfaces as well in the command line.

- Add control socket support and rtadvctl(8) utility to show the RA information
  in rtadvd(8).  Dumping by SIGUSR1 has been removed in favor of it.

1 files changed, 416 insertions, 263 deletions

diff --git a/usr.sbin/rtadvd/if.c b/usr.sbin/rtadvd/if.c
index 8722a05..b857356 100644
--- a/usr.sbin/rtadvd/if.c
+++ b/usr.sbin/rtadvd/if.c
@@ -3,6 +3,7 @@
 
 /*
  * 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
@@ -35,19 +36,24 @@
 #include <sys/sysctl.h>
 #include <sys/ioctl.h>
 #include <net/if.h>
+#include <net/if_dl.h>
 #include <net/if_types.h>
+#include <net/if_var.h>
 #include <net/ethernet.h>
-#include <ifaddrs.h>
 #include <net/route.h>
-#include <net/if_dl.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"
 
@@ -59,14 +65,34 @@
 	    ((ap)->sa_len ? ROUNDUP((ap)->sa_len, sizeof(u_long)) :	\
 	    sizeof(u_long)))
 
-struct if_msghdr **iflist;
-int iflist_init_ok;
-size_t ifblock_size;
-char *ifblock;
+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_iflist(char **buf, size_t *size);
-static void	parse_iflist(struct if_msghdr ***ifmlist_p,
-		    char *buf, size_t bufsize);
+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)
@@ -83,133 +109,6 @@ get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info)
 	}
 }
 
-struct sockaddr_dl *
-if_nametosdl(char *name)
-{
-	int mib[6] = {CTL_NET, AF_ROUTE, 0, 0, NET_RT_IFLIST, 0};
-	char *buf, *next, *lim;
-	size_t len;
-	struct if_msghdr *ifm;
-	struct sockaddr *sa, *rti_info[RTAX_MAX];
-	struct sockaddr_dl *sdl = NULL, *ret_sdl;
-
-	if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
-		return (NULL);
-	if ((buf = malloc(len)) == NULL)
-		return (NULL);
-	if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
-		free(buf);
-		return (NULL);
-	}
-
-	lim = buf + len;
-	for (next = buf; next < lim; next += ifm->ifm_msglen) {
-		ifm = (struct if_msghdr *)next;
-		if (ifm->ifm_version != RTM_VERSION) {
-			syslog(LOG_ERR,
-			    "<%s> RTM_VERSION mismatch (%d != %d).",
-			    __func__, ifm->ifm_version, RTM_VERSION);
-			continue;
-		}
-		if (ifm->ifm_type == RTM_IFINFO) {
-			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) {
-					sdl = (struct sockaddr_dl *)sa;
-					if (strlen(name) != sdl->sdl_nlen)
-						continue; /* not same len */
-					if (strncmp(&sdl->sdl_data[0],
-						    name,
-						    sdl->sdl_nlen) == 0) {
-						break;
-					}
-				}
-			}
-		}
-	}
-	if (next == lim) {
-		/* search failed */
-		free(buf);
-		return (NULL);
-	}
-
-	if ((ret_sdl = malloc(sdl->sdl_len)) == NULL)
-		goto end;
-	memcpy((caddr_t)ret_sdl, (caddr_t)sdl, sdl->sdl_len);
-
-end:
-	free(buf);
-	return (ret_sdl);
-}
-
-int
-if_getmtu(char *name)
-{
-	struct ifaddrs *ifap, *ifa;
-	struct if_data *ifd;
-	u_long mtu = 0;
-
-	if (getifaddrs(&ifap) < 0)
-		return (0);
-	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
-		if (strcmp(ifa->ifa_name, name) == 0) {
-			ifd = ifa->ifa_data;
-			if (ifd)
-				mtu = ifd->ifi_mtu;
-			break;
-		}
-	}
-	freeifaddrs(ifap);
-
-#ifdef SIOCGIFMTU		/* XXX: this ifdef may not be necessary */
-	if (mtu == 0) {
-		struct ifreq ifr;
-		int s;
-
-		if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
-			return (0);
-
-		ifr.ifr_addr.sa_family = AF_INET6;
-		strncpy(ifr.ifr_name, name,
-			sizeof(ifr.ifr_name));
-		if (ioctl(s, SIOCGIFMTU, (caddr_t)&ifr) < 0) {
-			close(s);
-			return (0);
-		}
-		close(s);
-
-		mtu = ifr.ifr_mtu;
-	}
-#endif
-
-	return (mtu);
-}
-
-/* give interface index and its old flags, then new flags returned */
-int
-if_getflags(int ifindex, int oifflags)
-{
-	struct ifreq ifr;
-	int s;
-
-	if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
-		syslog(LOG_ERR, "<%s> socket: %s", __func__,
-		    strerror(errno));
-		return (oifflags & ~IFF_UP);
-	}
-
-	if_indextoname(ifindex, ifr.ifr_name);
-	if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) {
-		syslog(LOG_ERR, "<%s> ioctl:SIOCGIFFLAGS: failed for %s",
-		    __func__, ifr.ifr_name);
-		close(s);
-		return (oifflags & ~IFF_UP);
-	}
-	close(s);
-	return (ifr.ifr_flags);
-}
-
 #define ROUNDUP8(a) (1 + (((a) - 1) | 7))
 int
 lladdropt_length(struct sockaddr_dl *sdl)
@@ -378,47 +277,23 @@ get_rtm_ifindex(char *buf)
 }
 
 int
-get_ifm_ifindex(char *buf)
-{
-	struct if_msghdr *ifm = (struct if_msghdr *)buf;
-
-	return ((int)ifm->ifm_index);
-}
-
-int
-get_ifam_ifindex(char *buf)
-{
-	struct ifa_msghdr *ifam = (struct ifa_msghdr *)buf;
-
-	return ((int)ifam->ifam_index);
-}
-
-int
-get_ifm_flags(char *buf)
-{
-	struct if_msghdr *ifm = (struct if_msghdr *)buf;
-
-	return (ifm->ifm_flags);
-}
-
-int
 get_prefixlen(char *buf)
 {
 	struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
 	struct sockaddr *sa, *rti_info[RTAX_MAX];
-	u_char *p, *lim;
+	char *p, *lim;
 
 	sa = (struct sockaddr *)(rtm + 1);
 	get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
 	sa = rti_info[RTAX_NETMASK];
 
-	p = (u_char *)(&SIN6(sa)->sin6_addr);
-	lim = (u_char *)sa + sa->sa_len;
+	p = (char *)(&SIN6(sa)->sin6_addr);
+	lim = (char *)sa + sa->sa_len;
 	return prefixlen(p, lim);
 }
 
 int
-prefixlen(u_char *p, u_char *lim)
+prefixlen(unsigned char *p, unsigned char *lim)
 {
 	int masklen;
 
@@ -458,140 +333,418 @@ prefixlen(u_char *p, u_char *lim)
 	return (masklen);
 }
 
-int
-rtmsg_type(char *buf)
+struct ifinfo *
+update_persist_ifinfo(struct ifilist_head_t *ifi_head, const char *ifname)
 {
-	struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
+	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;
+		}
+	}
 
-	return (rtm->rtm_type);
-}
+	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;
+		strncpy(ifi->ifi_ifname, ifname, sizeof(ifi->ifi_ifname)-1);
+		ifi->ifi_ifname[sizeof(ifi->ifi_ifname)-1] = '\0';
+		ifi->ifi_rainfo = NULL;
+		ifi->ifi_state = IFI_STATE_UNCONFIGURED;
+		TAILQ_INSERT_TAIL(ifi_head, ifi, ifi_next);
+	}
 
-int
-rtmsg_len(char *buf)
-{
-	struct rt_msghdr *rtm = (struct rt_msghdr *)buf;
+	ifi->ifi_persist = 1;
 
-	return (rtm->rtm_msglen);
+	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
-ifmsg_len(char *buf)
+update_ifinfo_nd_flags(struct ifinfo *ifi)
 {
-	struct if_msghdr *ifm = (struct if_msghdr *)buf;
+	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));
+	strncpy(nd.ifname, ifi->ifi_ifname,
+	    sizeof(nd.ifname));
+	error = ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd);
+	if (error) {
+		close(s);
+		syslog(LOG_ERR,
+		    "<%s> ioctl() failed.", __func__);
+		return (1);
+	}
+	ifi->ifi_nd_flags = nd.ndi.flags;
+	close(s);
 
-	return (ifm->ifm_msglen);
+	return (0);
 }
 
-/*
- * alloc buffer and get if_msghdrs block from kernel,
- * and put them into the buffer
- */
-static void
-get_iflist(char **buf, size_t *size)
+struct ifinfo *
+update_ifinfo(struct ifilist_head_t *ifi_head, int ifindex)
 {
-	int mib[6];
-
-	mib[0] = CTL_NET;
-	mib[1] = PF_ROUTE;
-	mib[2] = 0;
-	mib[3] = AF_INET6;
-	mib[4] = NET_RT_IFLIST;
-	mib[5] = 0;
-
-	if (sysctl(mib, 6, NULL, size, NULL, 0) < 0) {
-		syslog(LOG_ERR, "<%s> sysctl: iflist size get failed",
-		    __func__);
+	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;
+
+	syslog(LOG_DEBUG, "<%s> enter", __func__);
+
+	if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), NULL, &len, NULL, 0) <
+	    0) {
+		syslog(LOG_ERR,
+		    "<%s> sysctl: NET_RT_IFLIST size get failed", __func__);
 		exit(1);
 	}
-	if ((*buf = malloc(*size)) == NULL) {
+	if ((msg = malloc(len)) == NULL) {
 		syslog(LOG_ERR, "<%s> malloc failed", __func__);
 		exit(1);
 	}
-	if (sysctl(mib, 6, *buf, size, NULL, 0) < 0) {
-		syslog(LOG_ERR, "<%s> sysctl: iflist get failed",
-		     __func__);
+	if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), msg, &len, NULL, 0) <
+	    0) {
+		syslog(LOG_ERR,
+		    "<%s> sysctl: NET_RT_IFLIST get failed", __func__);
 		exit(1);
 	}
-	return;
-}
 
-/*
- * alloc buffer and parse if_msghdrs block passed as arg,
- * and init the buffer as list of pointers ot each of the if_msghdr.
- */
-static void
-parse_iflist(struct if_msghdr ***ifmlist_p, char *buf, size_t bufsize)
-{
-	int iflentry_size, malloc_size;
-	struct if_msghdr *ifm;
-	struct ifa_msghdr *ifam;
-	char *lim;
+	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;
 
-	/*
-	 * Estimate least size of an iflist entry, to be obtained from kernel.
-	 * Should add sizeof(sockaddr) ??
-	 */
-	iflentry_size = sizeof(struct if_msghdr);
-	/* roughly estimate max list size of pointers to each if_msghdr */
-	malloc_size = (bufsize/iflentry_size) * sizeof(size_t);
-	if ((*ifmlist_p = (struct if_msghdr **)malloc(malloc_size)) == NULL) {
-		syslog(LOG_ERR, "<%s> malloc failed", __func__);
-		exit(1);
-	}
+		syslog(LOG_DEBUG, "<%s> ifm = %p, lim = %p, diff = %zu",
+		    __func__, ifm, lim, (char *)lim - (char *)ifm);
 
-	lim = buf + bufsize;
-	for (ifm = (struct if_msghdr *)buf; ifm < (struct if_msghdr *)lim;) {
+		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 "
-			    "(buf=%p lim=%p ifm=%p)", __func__,
-			    buf, lim, ifm);
-			return;
+			syslog(LOG_WARNING,
+			    "<%s> ifm_msglen is 0", __func__);
+			free(msg);
+			return (NULL);
 		}
 
+		ifi_new = 0;
 		if (ifm->ifm_type == RTM_IFINFO) {
-			(*ifmlist_p)[ifm->ifm_index] = ifm;
+			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;
+
+			/* lookup an entry with the same ifindex */
+			TAILQ_FOREACH(ifi, ifi_head, ifi_next) {
+				if (ifm->ifm_index == ifi->ifi_ifindex)
+					break;
+				if_indextoname(ifm->ifm_index, ifname);
+				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 */
+			if_indextoname(ifm->ifm_index, ifi->ifi_ifname);
+			if (ifi->ifi_ifname == NULL) {
+				syslog(LOG_WARNING,
+				    "<%s> ifname not found (idx=%d)",
+				    __func__, ifm->ifm_index);
+				if (ifi_new)
+					free(ifi);
+				continue;
+			}
+
+			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;
+				strncpy(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"
-			    "buf:%p, ifm:%p, lim:%p\n",
-			    RTM_IFINFO, ifm->ifm_type, ifm->ifm_msglen,
-			    buf, ifm, lim);
-			exit (1);
+			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);
 		}
-		for (ifam = (struct ifa_msghdr *)
-			((char *)ifm + ifm->ifm_msglen);
-		     ifam < (struct ifa_msghdr *)lim;
-		     ifam = (struct ifa_msghdr *)
-		     	((char *)ifam + ifam->ifam_msglen)) {
-			/* just for safety */
-			if (!ifam->ifam_msglen) {
-				syslog(LOG_WARNING, "<%s> ifa_msglen is 0 "
-				    "(buf=%p lim=%p ifam=%p)", __func__,
-				    buf, lim, ifam);
-				return;
-			}
-			if (ifam->ifam_type != RTM_NEWADDR)
-				break;
+
+		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);
 		}
-		ifm = (struct if_msghdr *)ifam;
 	}
+	free(msg);
+
+	if (mcastif != NULL) {
+		error = sock_mc_rr_update(&sock, mcastif);
+		if (error)
+			exit(1);
+	}
+
+	return (ifi);
 }
 
-void
-init_iflist(void)
+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> generate iflist.", __func__);
+	    "<%s> %s: join link-local all-routers MC group",
+	    __func__, if_indextoname(ifindex, ifname));
 
-	if (ifblock) {
-		free(ifblock);
-		ifblock_size = 0;
+	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);
 	}
-	if (iflist)
-		free(iflist);
-	/* get iflist block from kernel */
-	get_iflist(&ifblock, &ifblock_size);
 
-	/* make list of pointers to each if_msghdr */
-	parse_iflist(&iflist, ifblock, ifblock_size);
+	syslog(LOG_DEBUG,
+	    "<%s> %s: join site-local all-routers MC group",
+	    __func__, mif);
+
+	return (0);
 }