xref: /openbsd-src/usr.sbin/ospf6d/kroute.c (revision 018a085a0a42a5ac0134c8e54842d4b413e0ddbc)

/*	$OpenBSD: kroute.c,v 1.70 2025/01/02 06:35:57 anton Exp $ */

/*
 * Copyright (c) 2004 Esben Norby <norby@openbsd.org>
 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/tree.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>

#include "ospf6d.h"
#include "ospfe.h"
#include "log.h"

struct {
	u_int32_t		rtseq;
	pid_t			pid;
	int			fib_sync;
	int			fib_serial;
	u_int8_t		fib_prio;
	int			fd;
	struct event		ev;
	struct event		reload;
	u_int			rdomain;
#define KR_RELOAD_IDLE 0
#define KR_RELOAD_FETCH        1
#define KR_RELOAD_HOLD 2
	int                     reload_state;
} kr_state;

struct kroute_node {
	RB_ENTRY(kroute_node)	 entry;
	struct kroute_node	*next;
	struct kroute		 r;
	int			 serial;
};

void	kr_redist_remove(struct kroute_node *, struct kroute_node *);
int	kr_redist_eval(struct kroute *, struct kroute *);
void	kr_redistribute(struct kroute_node *);
int	kroute_compare(struct kroute_node *, struct kroute_node *);
int	kr_change_fib(struct kroute_node *, struct kroute *, int, int);
int	kr_delete_fib(struct kroute_node *);

struct kroute_node	*kroute_find(const struct in6_addr *, u_int8_t,
			    u_int8_t);
struct kroute_node	*kroute_matchgw(struct kroute_node *,
			    struct in6_addr *, unsigned int);
int			 kroute_insert(struct kroute_node *);
int			 kroute_remove(struct kroute_node *);
void			 kroute_clear(void);

struct iface		*kif_update(u_short, int, struct if_data *,
			   struct sockaddr_dl *);
int			 kif_validate(u_short);

struct kroute_node	*kroute_match(struct in6_addr *);

int		protect_lo(void);
void		get_rtaddrs(int, struct sockaddr *, struct sockaddr **);
void		if_change(u_short, int, struct if_data *, struct sockaddr_dl *);
void		if_newaddr(u_short, struct sockaddr_in6 *,
		    struct sockaddr_in6 *, struct sockaddr_in6 *);
void		if_deladdr(u_short, struct sockaddr_in6 *,
		    struct sockaddr_in6 *, struct sockaddr_in6 *);
void		if_announce(void *);

int		send_rtmsg(int, int, struct kroute *);
int		dispatch_rtmsg(void);
int		fetchtable(void);
int		rtmsg_process(char *, size_t);
void		kr_fib_reload_timer(int, short, void *);
void		kr_fib_reload_arm_timer(int);

RB_HEAD(kroute_tree, kroute_node)	krt;
RB_PROTOTYPE(kroute_tree, kroute_node, entry, kroute_compare)
RB_GENERATE(kroute_tree, kroute_node, entry, kroute_compare)

int
kr_init(int fs, u_int rdomain, int redis_label_or_prefix, u_int8_t fib_prio)
{
	int		opt = 0, rcvbuf, default_rcvbuf;
	socklen_t	optlen;
	int		filter_prio = fib_prio;
	int		filter_flags = RTF_LLINFO | RTF_BROADCAST;

	kr_state.fib_sync = fs;
	kr_state.rdomain = rdomain;
	kr_state.fib_prio = fib_prio;

	if ((kr_state.fd = socket(AF_ROUTE,
	    SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, AF_INET6)) == -1) {
		log_warn("kr_init: socket");
		return (-1);
	}

	/* not interested in my own messages */
	if (setsockopt(kr_state.fd, SOL_SOCKET, SO_USELOOPBACK,
	    &opt, sizeof(opt)) == -1)
		log_warn("kr_init: setsockopt");	/* not fatal */

	if (redis_label_or_prefix) {
		filter_prio = 0;
		log_info("%s: priority filter disabled", __func__);
	} else
		log_debug("%s: priority filter enabled", __func__);

	if (setsockopt(kr_state.fd, AF_ROUTE, ROUTE_PRIOFILTER, &filter_prio,
	    sizeof(filter_prio)) == -1) {
		log_warn("%s: setsockopt AF_ROUTE ROUTE_PRIOFILTER", __func__);
		/* not fatal */
	}

	if (setsockopt(kr_state.fd, AF_ROUTE, ROUTE_FLAGFILTER, &filter_flags,
	    sizeof(filter_flags)) == -1) {
		log_warn("%s: setsockopt AF_ROUTE ROUTE_FLAGFILTER", __func__);
		/* not fatal */
	}

	/* grow receive buffer, don't wanna miss messages */
	optlen = sizeof(default_rcvbuf);
	if (getsockopt(kr_state.fd, SOL_SOCKET, SO_RCVBUF,
	    &default_rcvbuf, &optlen) == -1)
		log_warn("kr_init getsockopt SOL_SOCKET SO_RCVBUF");
	else
		for (rcvbuf = MAX_RTSOCK_BUF;
		    rcvbuf > default_rcvbuf &&
		    setsockopt(kr_state.fd, SOL_SOCKET, SO_RCVBUF,
		    &rcvbuf, sizeof(rcvbuf)) == -1 && errno == ENOBUFS;
		    rcvbuf /= 2)
			;	/* nothing */

	kr_state.pid = getpid();
	kr_state.rtseq = 1;

	RB_INIT(&krt);

	if (fetchtable() == -1)
		return (-1);

	if (protect_lo() == -1)
		return (-1);

	event_set(&kr_state.ev, kr_state.fd, EV_READ | EV_PERSIST,
	    kr_dispatch_msg, NULL);
	event_add(&kr_state.ev, NULL);

	kr_state.reload_state = KR_RELOAD_IDLE;
	evtimer_set(&kr_state.reload, kr_fib_reload_timer, NULL);

	return (0);
}

int
kr_change_fib(struct kroute_node *kr, struct kroute *kroute, int krcount,
    int action)
{
	int			 i;
	struct kroute_node	*kn, *nkn;

	if (action == RTM_ADD) {
		/*
		 * First remove all stale multipath routes.
		 * This step must be skipped when the action is RTM_CHANGE
		 * because it is already a single path route that will be
		 * changed.
		 */
		for (kn = kr; kn != NULL; kn = nkn) {
			for (i = 0; i < krcount; i++) {
				if (kn->r.scope == kroute[i].scope &&
				    IN6_ARE_ADDR_EQUAL(&kn->r.nexthop,
				    &kroute[i].nexthop))
					break;
			}
			nkn = kn->next;
			if (i == krcount) {
				/* stale route */
				if (kr_delete_fib(kn) == -1)
					log_warnx("kr_delete_fib failed");
				/*
				 * if head element was removed we need to adjust
				 * the head
				 */
				if (kr == kn)
					kr = nkn;
			}
		}
	}

	/*
	 * now add or change the route
	 */
	for (i = 0; i < krcount; i++) {
		/* nexthop ::1 -> ignore silently */
		if (IN6_IS_ADDR_LOOPBACK(&kroute[i].nexthop))
			continue;

		if (action == RTM_ADD && kr) {
			for (kn = kr; kn != NULL; kn = kn->next) {
				if (kn->r.scope == kroute[i].scope &&
				    IN6_ARE_ADDR_EQUAL(&kn->r.nexthop,
				    &kroute[i].nexthop))
					break;
			}

			if (kn != NULL)
				/* nexthop already present, skip it */
				continue;
		} else
			/* modify first entry */
			kn = kr;

		/* send update */
		if (send_rtmsg(kr_state.fd, action, &kroute[i]) == -1)
			return (-1);

		/* create new entry unless we are changing the first entry */
		if (action == RTM_ADD)
			if ((kn = calloc(1, sizeof(*kn))) == NULL)
				fatal(NULL);

		kn->r.prefix = kroute[i].prefix;
		kn->r.prefixlen = kroute[i].prefixlen;
		kn->r.nexthop = kroute[i].nexthop;
		kn->r.scope = kroute[i].scope;
		kn->r.flags = kroute[i].flags | F_OSPFD_INSERTED;
		kn->r.priority = kr_state.fib_prio;
		kn->r.ext_tag = kroute[i].ext_tag;
		rtlabel_unref(kn->r.rtlabel);	/* for RTM_CHANGE */
		kn->r.rtlabel = kroute[i].rtlabel;

		if (action == RTM_ADD)
			if (kroute_insert(kn) == -1) {
				log_debug("kr_update_fib: cannot insert %s",
				    log_in6addr(&kn->r.nexthop));
				free(kn);
			}
		action = RTM_ADD;
	}
	return  (0);
}

int
kr_change(struct kroute *kroute, int krcount)
{
	struct kroute_node	*kr;
	int			 action = RTM_ADD;

	kroute->rtlabel = rtlabel_tag2id(kroute->ext_tag);

	kr = kroute_find(&kroute->prefix, kroute->prefixlen, kr_state.fib_prio);
	if (kr != NULL && kr->next == NULL && krcount == 1) {
		/*
		 * single path OSPF route.
		 * The kernel does not allow to change a gateway route to a
		 * cloning route or contrary. In this case remove and add the
		 * route, otherwise change the existing one.
		 */
		if ((IN6_IS_ADDR_UNSPECIFIED(&kroute->nexthop) &&
		    !IN6_IS_ADDR_UNSPECIFIED(&kr->r.nexthop)) ||
		    (!IN6_IS_ADDR_UNSPECIFIED(&kroute->nexthop) &&
		    IN6_IS_ADDR_UNSPECIFIED(&kr->r.nexthop))) {
			if (kr_delete_fib(kr) == 0)
				kr = NULL;
			else {
				log_warn("kr_change: failed to remove route: "
				    "%s/%d", log_in6addr(&kr->r.prefix),
				    kr->r.prefixlen);
				return (-1);
			}
		} else
			action = RTM_CHANGE;
	}

	return (kr_change_fib(kr, kroute, krcount, action));
}

int
kr_delete_fib(struct kroute_node *kr)
{
	if (kr->r.priority != kr_state.fib_prio)
		log_warn("kr_delete_fib: %s/%d has wrong priority %d",
		    log_in6addr(&kr->r.prefix), kr->r.prefixlen,
		    kr->r.priority);

	if (send_rtmsg(kr_state.fd, RTM_DELETE, &kr->r) == -1)
		return (-1);

	if (kroute_remove(kr) == -1)
		return (-1);

	return (0);
}

int
kr_delete(struct kroute *kroute)
{
	struct kroute_node	*kr, *nkr;

	if ((kr = kroute_find(&kroute->prefix, kroute->prefixlen,
	    kr_state.fib_prio)) == NULL)
		return (0);

	while (kr != NULL) {
		nkr = kr->next;
		if (kr_delete_fib(kr) == -1)
			return (-1);
		kr = nkr;
	}

	return (0);
}

void
kr_shutdown(void)
{
	kr_fib_decouple();
	kroute_clear();
}

void
kr_fib_couple(void)
{
	struct kroute_node	*kr;
	struct kroute_node	*kn;

	if (kr_state.fib_sync == 1)	/* already coupled */
		return;

	kr_state.fib_sync = 1;

	RB_FOREACH(kr, kroute_tree, &krt)
		if (kr->r.priority == kr_state.fib_prio)
			for (kn = kr; kn != NULL; kn = kn->next)
				send_rtmsg(kr_state.fd, RTM_ADD, &kn->r);

	log_info("kernel routing table coupled");
}

void
kr_fib_decouple(void)
{
	struct kroute_node	*kr;
	struct kroute_node	*kn;

	if (kr_state.fib_sync == 0)	/* already decoupled */
		return;

	RB_FOREACH(kr, kroute_tree, &krt)
		if (kr->r.priority == kr_state.fib_prio)
			for (kn = kr; kn != NULL; kn = kn->next)
				send_rtmsg(kr_state.fd, RTM_DELETE, &kn->r);

	kr_state.fib_sync = 0;

	log_info("kernel routing table decoupled");
}

void
kr_fib_reload_timer(int fd, short event, void *bula)
{
	if (kr_state.reload_state == KR_RELOAD_FETCH) {
		kr_fib_reload();
		kr_state.reload_state = KR_RELOAD_HOLD;
		kr_fib_reload_arm_timer(KR_RELOAD_HOLD_TIMER);
	} else {
		kr_state.reload_state = KR_RELOAD_IDLE;
	}
}

void
kr_fib_reload_arm_timer(int delay)
{
	struct timeval		tv;

	timerclear(&tv);
	tv.tv_sec = delay / 1000;
	tv.tv_usec = (delay % 1000) * 1000;

	if (evtimer_add(&kr_state.reload, &tv) == -1)
		fatal("add_reload_timer");
}

void
kr_fib_reload(void)
{
	struct kroute_node	*krn, *kr, *kn;

	log_info("reloading interface list and routing table");

	kr_state.fib_serial++;

	if (fetchifs(0) != 0 || fetchtable() != 0)
		return;

	for (kr = RB_MIN(kroute_tree, &krt); kr != NULL; kr = krn) {
		krn = RB_NEXT(kroute_tree, &krt, kr);

		do {
			kn = kr->next;

			if (kr->serial != kr_state.fib_serial) {

				if (kr->r.priority == kr_state.fib_prio) {
					kr->serial = kr_state.fib_serial;
					if (send_rtmsg(kr_state.fd,
					    RTM_ADD, &kr->r) != 0)
						break;
				} else
					kroute_remove(kr);
			}

		} while ((kr = kn) != NULL);
	}
}

void
kr_fib_update_prio(u_int8_t fib_prio)
{
	struct kroute_node	*kr;

	RB_FOREACH(kr, kroute_tree, &krt)
		if ((kr->r.flags & F_OSPFD_INSERTED))
			kr->r.priority = fib_prio;

	log_info("fib priority changed from %hhu to %hhu", kr_state.fib_prio,
	    fib_prio);

	kr_state.fib_prio = fib_prio;
}

void
kr_dispatch_msg(int fd, short event, void *bula)
{
	/* XXX this is stupid */
	dispatch_rtmsg();
}

void
kr_show_route(struct imsg *imsg)
{
	struct kroute_node	*kr;
	struct kroute_node	*kn;
	int			 flags;
	struct in6_addr		 addr;

	switch (imsg->hdr.type) {
	case IMSG_CTL_KROUTE:
		if (imsg->hdr.len != IMSG_HEADER_SIZE + sizeof(flags)) {
			log_warnx("kr_show_route: wrong imsg len");
			return;
		}
		memcpy(&flags, imsg->data, sizeof(flags));
		RB_FOREACH(kr, kroute_tree, &krt)
			if (!flags || kr->r.flags & flags) {
				kn = kr;
				do {
					main_imsg_compose_ospfe(IMSG_CTL_KROUTE,
					    imsg->hdr.pid,
					    &kn->r, sizeof(kn->r));
				} while ((kn = kn->next) != NULL);
			}
		break;
	case IMSG_CTL_KROUTE_ADDR:
		if (imsg->hdr.len != IMSG_HEADER_SIZE +
		    sizeof(struct in6_addr)) {
			log_warnx("kr_show_route: wrong imsg len");
			return;
		}
		memcpy(&addr, imsg->data, sizeof(addr));
		kr = kroute_match(&addr);
		if (kr != NULL)
			main_imsg_compose_ospfe(IMSG_CTL_KROUTE, imsg->hdr.pid,
			    &kr->r, sizeof(kr->r));
		break;
	default:
		log_debug("kr_show_route: error handling imsg");
		break;
	}

	main_imsg_compose_ospfe(IMSG_CTL_END, imsg->hdr.pid, NULL, 0);
}

void
kr_redist_remove(struct kroute_node *kh, struct kroute_node *kn)
{
	struct kroute	 *kr;

	/* was the route redistributed? */
	if ((kn->r.flags & F_REDISTRIBUTED) == 0)
		return;

	/* remove redistributed flag */
	kn->r.flags &= ~F_REDISTRIBUTED;
	kr = &kn->r;

	/* probably inform the RDE (check if no other path is redistributed) */
	for (kn = kh; kn; kn = kn->next)
		if (kn->r.flags & F_REDISTRIBUTED)
			break;

	if (kn == NULL)
		main_imsg_compose_rde(IMSG_NETWORK_DEL, 0, kr,
		    sizeof(struct kroute));
}

int
kr_redist_eval(struct kroute *kr, struct kroute *new_kr)
{
	u_int32_t	 metric = 0;

	/* Only non-ospfd routes are considered for redistribution. */
	if (!(kr->flags & F_KERNEL))
		goto dont_redistribute;

	/* Dynamic routes are not redistributable. */
	if (kr->flags & F_DYNAMIC)
		goto dont_redistribute;

	/* interface is not up and running so don't announce */
	if (kr->flags & F_DOWN)
		goto dont_redistribute;

	/*
	 * We consider loopback, multicast, link- and site-local,
	 * IPv4 mapped and IPv4 compatible addresses as not redistributable.
	 */
	if (IN6_IS_ADDR_LOOPBACK(&kr->prefix) ||
	    IN6_IS_ADDR_MULTICAST(&kr->prefix) ||
	    IN6_IS_ADDR_LINKLOCAL(&kr->prefix) ||
	    IN6_IS_ADDR_SITELOCAL(&kr->prefix) ||
	    IN6_IS_ADDR_V4MAPPED(&kr->prefix) ||
	    IN6_IS_ADDR_V4COMPAT(&kr->prefix))
		goto dont_redistribute;
	/*
	 * Consider networks with nexthop loopback as not redistributable
	 * unless it is a reject or blackhole route.
	 */
	if (IN6_IS_ADDR_LOOPBACK(&kr->nexthop) &&
	    !(kr->flags & (F_BLACKHOLE|F_REJECT)))
		goto dont_redistribute;

	/* Should we redistribute this route? */
	if (!ospf_redistribute(kr, &metric))
		goto dont_redistribute;

	/* prefix should be redistributed */
	kr->flags |= F_REDISTRIBUTED;
	/*
	 * only one of all multipath routes can be redistributed so
	 * redistribute the best one.
	 */
	if (new_kr->metric > metric) {
		*new_kr = *kr;
		new_kr->metric = metric;
	}

	return (1);

dont_redistribute:
	/* was the route redistributed? */
	if ((kr->flags & F_REDISTRIBUTED) == 0)
		return (0);

	kr->flags &= ~F_REDISTRIBUTED;
	return (1);
}

void
kr_redistribute(struct kroute_node *kh)
{
	struct kroute_node	*kn;
	struct kroute		 kr;
	int			 redistribute = 0;

	/* only the highest prio route can be redistributed */
	if (kroute_find(&kh->r.prefix, kh->r.prefixlen, RTP_ANY) != kh)
		return;

	bzero(&kr, sizeof(kr));
	kr.metric = UINT_MAX;
	for (kn = kh; kn; kn = kn->next)
		if (kr_redist_eval(&kn->r, &kr))
			redistribute = 1;

	if (!redistribute)
		return;

	if (kr.flags & F_REDISTRIBUTED) {
		main_imsg_compose_rde(IMSG_NETWORK_ADD, 0, &kr,
		    sizeof(struct kroute));
	} else {
		kr = kh->r;
		main_imsg_compose_rde(IMSG_NETWORK_DEL, 0, &kr,
		    sizeof(struct kroute));
	}
}

void
kr_reload(int redis_label_or_prefix)
{
	struct kroute_node	*kr, *kn;
	u_int32_t		 dummy;
	int			 r;
	int			 filter_prio = kr_state.fib_prio;

	/* update the priority filter */
	if (redis_label_or_prefix) {
		filter_prio = 0;
		log_info("%s: priority filter disabled", __func__);
	} else
		log_debug("%s: priority filter enabled", __func__);

	if (setsockopt(kr_state.fd, AF_ROUTE, ROUTE_PRIOFILTER, &filter_prio,
	    sizeof(filter_prio)) == -1) {
		log_warn("%s: setsockopt AF_ROUTE ROUTE_PRIOFILTER", __func__);
		/* not fatal */
	}

	RB_FOREACH(kr, kroute_tree, &krt) {
		for (kn = kr; kn; kn = kn->next) {
			r = ospf_redistribute(&kn->r, &dummy);
			/*
			 * if it is redistributed, redistribute again metric
			 * may have changed.
			 */
			if ((kn->r.flags & F_REDISTRIBUTED && !r) || r)
				break;
		}
		if (kn) {
			/*
			 * kr_redistribute copes with removes and RDE with
			 * duplicates
			 */
			kr_redistribute(kr);
		}
	}
}

/* rb-tree compare */
int
kroute_compare(struct kroute_node *a, struct kroute_node *b)
{
	int	i;

	/* XXX maybe switch a & b */
	i = memcmp(&a->r.prefix, &b->r.prefix, sizeof(a->r.prefix));
	if (i)
		return (i);
	if (a->r.prefixlen < b->r.prefixlen)
		return (-1);
	if (a->r.prefixlen > b->r.prefixlen)
		return (1);

	/* if the priority is RTP_ANY finish on the first address hit */
	if (a->r.priority == RTP_ANY || b->r.priority == RTP_ANY)
		return (0);
	if (a->r.priority < b->r.priority)
		return (-1);
	if (a->r.priority > b->r.priority)
		return (1);
	return (0);
}

/* tree management */
struct kroute_node *
kroute_find(const struct in6_addr *prefix, u_int8_t prefixlen, u_int8_t prio)
{
	struct kroute_node	s;
	struct kroute_node	*kn, *tmp;

	s.r.prefix = *prefix;
	s.r.prefixlen = prefixlen;
	s.r.priority = prio;

	kn = RB_FIND(kroute_tree, &krt, &s);
	if (kn && prio == RTP_ANY) {
		tmp = RB_PREV(kroute_tree, &krt, kn);
		while (tmp) {
			if (kroute_compare(&s, tmp) == 0)
				kn = tmp;
			else
				break;
			tmp = RB_PREV(kroute_tree, &krt, kn);
		}
	}
	return (kn);
}

struct kroute_node *
kroute_matchgw(struct kroute_node *kr, struct in6_addr *nh, unsigned int scope)
{
	while (kr) {
		if (scope == kr->r.scope &&
		    IN6_ARE_ADDR_EQUAL(&kr->r.nexthop, nh))
			return (kr);
		kr = kr->next;
	}

	return (NULL);
}

int
kroute_insert(struct kroute_node *kr)
{
	struct kroute_node	*krm, *krh;

	kr->serial = kr_state.fib_serial;

	if ((krh = RB_INSERT(kroute_tree, &krt, kr)) != NULL) {
		/*
		 * Multipath route, add at end of list.
		 */
		krm = krh;
		while (krm->next != NULL)
			krm = krm->next;
		krm->next = kr;
		kr->next = NULL; /* to be sure */
	} else
		krh = kr;

	if (!(kr->r.flags & F_KERNEL)) {
		/* don't validate or redistribute ospf route */
		kr->r.flags &= ~F_DOWN;
		return (0);
	}

	if (kif_validate(kr->r.ifindex))
		kr->r.flags &= ~F_DOWN;
	else
		kr->r.flags |= F_DOWN;

	kr_redistribute(krh);
	return (0);
}

int
kroute_remove(struct kroute_node *kr)
{
	struct kroute_node	*krm;

	if ((krm = RB_FIND(kroute_tree, &krt, kr)) == NULL) {
		log_warnx("kroute_remove failed to find %s/%u",
		    log_in6addr(&kr->r.prefix), kr->r.prefixlen);
		return (-1);
	}

	if (krm == kr) {
		/* head element */
		if (RB_REMOVE(kroute_tree, &krt, kr) == NULL) {
			log_warnx("kroute_remove failed for %s/%u",
			    log_in6addr(&kr->r.prefix), kr->r.prefixlen);
			return (-1);
		}
		if (kr->next != NULL) {
			if (RB_INSERT(kroute_tree, &krt, kr->next) != NULL) {
				log_warnx("kroute_remove failed to add %s/%u",
				    log_in6addr(&kr->r.prefix),
				    kr->r.prefixlen);
				return (-1);
			}
		}
	} else {
		/* somewhere in the list */
		while (krm->next != kr && krm->next != NULL)
			krm = krm->next;
		if (krm->next == NULL) {
			log_warnx("kroute_remove multipath list corrupted "
			    "for %s/%u", log_in6addr(&kr->r.prefix),
			    kr->r.prefixlen);
			return (-1);
		}
		krm->next = kr->next;
	}

	kr_redist_remove(krm, kr);
	rtlabel_unref(kr->r.rtlabel);

	free(kr);
	return (0);
}

void
kroute_clear(void)
{
	struct kroute_node	*kr;

	while ((kr = RB_MIN(kroute_tree, &krt)) != NULL)
		kroute_remove(kr);
}

struct iface *
kif_update(u_short ifindex, int flags, struct if_data *ifd,
    struct sockaddr_dl *sdl)
{
	struct iface	*iface;
	char		 ifname[IF_NAMESIZE];

	if ((iface = if_find(ifindex)) == NULL) {
		bzero(ifname, sizeof(ifname));
		if (sdl && sdl->sdl_family == AF_LINK) {
			if (sdl->sdl_nlen >= sizeof(ifname))
				memcpy(ifname, sdl->sdl_data,
				    sizeof(ifname) - 1);
			else if (sdl->sdl_nlen > 0)
				memcpy(ifname, sdl->sdl_data, sdl->sdl_nlen);
			else
				return (NULL);
		} else
			return (NULL);
		if ((iface = if_new(ifindex, ifname)) == NULL)
			return (NULL);
	}

	if_update(iface, ifd->ifi_mtu, flags, ifd->ifi_type,
	    ifd->ifi_link_state, ifd->ifi_baudrate, ifd->ifi_rdomain);

	return (iface);
}

int
kif_validate(u_short ifindex)
{
	struct iface	*iface;

	if ((iface = if_find(ifindex)) == NULL) {
		log_warnx("interface with index %u not found", ifindex);
		return (-1);
	}

	return ((iface->flags & IFF_UP) && LINK_STATE_IS_UP(iface->linkstate));
}

struct kroute_node *
kroute_match(struct in6_addr *key)
{
	int			 i;
	struct kroute_node	*kr;
	struct in6_addr		 ina;

	/* we will never match the default route */
	for (i = 128; i > 0; i--) {
		inet6applymask(&ina, key, i);
		if ((kr = kroute_find(&ina, i, RTP_ANY)) != NULL)
			return (kr);
	}

	/* if we don't have a match yet, try to find a default route */
	if ((kr = kroute_find(&in6addr_any, 0, RTP_ANY)) != NULL)
			return (kr);

	return (NULL);
}

/* misc */
int
protect_lo(void)
{
	struct kroute_node	*kr;

	/* special protection for loopback */
	if ((kr = calloc(1, sizeof(struct kroute_node))) == NULL) {
		log_warn("protect_lo");
		return (-1);
	}
	memcpy(&kr->r.prefix, &in6addr_loopback, sizeof(kr->r.prefix));
	kr->r.prefixlen = 128;
	kr->r.flags = F_KERNEL|F_CONNECTED;

	if (RB_INSERT(kroute_tree, &krt, kr) != NULL)
		free(kr);	/* kernel route already there, no problem */

	return (0);
}

#define ROUNDUP(a) \
	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))

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;
			sa = (struct sockaddr *)((char *)(sa) +
			    ROUNDUP(sa->sa_len));
		} else
			rti_info[i] = NULL;
	}
}

void
if_change(u_short ifindex, int flags, struct if_data *ifd,
    struct sockaddr_dl *sdl)
{
	struct kroute_node	*kr, *tkr;
	struct iface		*iface;
	u_int8_t		 wasvalid, isvalid;

	wasvalid = kif_validate(ifindex);

	if ((iface = kif_update(ifindex, flags, ifd, sdl)) == NULL) {
		log_warn("if_change: kif_update(%u)", ifindex);
		return;
	}

	/* inform engine and rde about state change */
	main_imsg_compose_rde(IMSG_IFINFO, 0, iface, sizeof(struct iface));
	main_imsg_compose_ospfe(IMSG_IFINFO, 0, iface, sizeof(struct iface));

	isvalid = (iface->flags & IFF_UP) &&
	    LINK_STATE_IS_UP(iface->linkstate);

	if (wasvalid == isvalid)
		return;		/* nothing changed wrt validity */

	/* update redistribute list */
	RB_FOREACH(kr, kroute_tree, &krt) {
		for (tkr = kr; tkr != NULL; tkr = tkr->next) {
			if (tkr->r.ifindex == ifindex) {
				if (isvalid)
					tkr->r.flags &= ~F_DOWN;
				else
					tkr->r.flags |= F_DOWN;

			}
		}
		kr_redistribute(kr);
	}
}

void
if_newaddr(u_short ifindex, struct sockaddr_in6 *ifa, struct sockaddr_in6 *mask,
    struct sockaddr_in6 *brd)
{
	struct iface		*iface;
	struct iface_addr	*ia;
	struct ifaddrchange	 ifc;

	if (ifa == NULL || ifa->sin6_family != AF_INET6)
		return;
	if ((iface = if_find(ifindex)) == NULL) {
		log_warnx("if_newaddr: corresponding if %d not found", ifindex);
		return;
	}

	/* We only care about link-local and global-scope. */
	if (IN6_IS_ADDR_UNSPECIFIED(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_LOOPBACK(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_MULTICAST(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_SITELOCAL(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_V4MAPPED(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_V4COMPAT(&ifa->sin6_addr))
		return;

	clearscope(&ifa->sin6_addr);

	if (IN6_IS_ADDR_LINKLOCAL(&ifa->sin6_addr) ||
	    iface->flags & IFF_LOOPBACK)
		iface->addr = ifa->sin6_addr;

	if ((ia = calloc(1, sizeof(struct iface_addr))) == NULL)
		fatal("if_newaddr");

	ia->addr = ifa->sin6_addr;

	if (mask)
		ia->prefixlen = mask2prefixlen(mask);
	else
		ia->prefixlen = 0;
	if (brd && brd->sin6_family == AF_INET6)
		ia->dstbrd = brd->sin6_addr;
	else
		bzero(&ia->dstbrd, sizeof(ia->dstbrd));

	switch (iface->type) {
	case IF_TYPE_BROADCAST:
	case IF_TYPE_NBMA:
		log_debug("if_newaddr: ifindex %u, addr %s/%d",
		    ifindex, log_in6addr(&ia->addr), ia->prefixlen);
		break;
	case IF_TYPE_VIRTUALLINK:	/* FIXME */
		break;
	case IF_TYPE_POINTOPOINT:
	case IF_TYPE_POINTOMULTIPOINT:
		log_debug("if_newaddr: ifindex %u, addr %s/%d, "
		    "dest %s", ifindex, log_in6addr(&ia->addr),
		    ia->prefixlen, log_in6addr(&ia->dstbrd));
		break;
	default:
		fatalx("if_newaddr: unknown interface type");
	}

	TAILQ_INSERT_TAIL(&iface->ifa_list, ia, entry);
	/* inform engine and rde if interface is used */
	if (iface->cflags & F_IFACE_CONFIGURED) {
		ifc.addr = ia->addr;
		ifc.dstbrd = ia->dstbrd;
		ifc.prefixlen = ia->prefixlen;
		ifc.ifindex = ifindex;
		main_imsg_compose_ospfe(IMSG_IFADDRNEW, 0, &ifc, sizeof(ifc));
		main_imsg_compose_rde(IMSG_IFADDRNEW, 0, &ifc, sizeof(ifc));
	}
}

void
if_deladdr(u_short ifindex, struct sockaddr_in6 *ifa, struct sockaddr_in6 *mask,
    struct sockaddr_in6 *brd)
{
	struct iface		*iface;
	struct iface_addr	*ia, *nia;
	struct ifaddrchange	 ifc;

	if (ifa == NULL || ifa->sin6_family != AF_INET6)
		return;
	if ((iface = if_find(ifindex)) == NULL) {
		log_warnx("if_deladdr: corresponding if %d not found", ifindex);
		return;
	}

	/* We only care about link-local and global-scope. */
	if (IN6_IS_ADDR_UNSPECIFIED(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_LOOPBACK(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_MULTICAST(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_SITELOCAL(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_V4MAPPED(&ifa->sin6_addr) ||
	    IN6_IS_ADDR_V4COMPAT(&ifa->sin6_addr))
		return;

	clearscope(&ifa->sin6_addr);

	for (ia = TAILQ_FIRST(&iface->ifa_list); ia != NULL; ia = nia) {
		nia = TAILQ_NEXT(ia, entry);

		if (IN6_ARE_ADDR_EQUAL(&ia->addr, &ifa->sin6_addr)) {
			log_debug("if_deladdr: ifindex %u, addr %s/%d",
			    ifindex, log_in6addr(&ia->addr), ia->prefixlen);
			TAILQ_REMOVE(&iface->ifa_list, ia, entry);
			/* inform engine and rde if interface is used */
			if (iface->cflags & F_IFACE_CONFIGURED) {
				ifc.addr = ia->addr;
				ifc.dstbrd = ia->dstbrd;
				ifc.prefixlen = ia->prefixlen;
				ifc.ifindex = ifindex;
				main_imsg_compose_ospfe(IMSG_IFADDRDEL, 0, &ifc,
				    sizeof(ifc));
				main_imsg_compose_rde(IMSG_IFADDRDEL, 0, &ifc,
				    sizeof(ifc));
			}
			free(ia);
			return;
		}
	}
}

void
if_announce(void *msg)
{
	struct if_announcemsghdr	*ifan;
	struct iface			*iface;

	ifan = msg;

	switch (ifan->ifan_what) {
	case IFAN_ARRIVAL:
		if ((iface = if_new(ifan->ifan_index, ifan->ifan_name)) == NULL)
			fatal("if_announce failed");
		break;
	case IFAN_DEPARTURE:
		iface = if_find(ifan->ifan_index);
		if (iface != NULL)
			if_del(iface);
		break;
	}
}

/* rtsock */
int
send_rtmsg(int fd, int action, struct kroute *kroute)
{
	struct iovec		iov[5];
	struct rt_msghdr	hdr;
	struct pad {
		struct sockaddr_in6	addr;
		char			pad[sizeof(long)]; /* thank you IPv6 */
	} prefix, nexthop, mask;
	struct {
		struct sockaddr_dl	addr;
		char			pad[sizeof(long)];
	} ifp;
	struct sockaddr_rtlabel	sa_rl;
	int			iovcnt = 0;
	const char		*label;

	if (kr_state.fib_sync == 0)
		return (0);

	/* initialize header */
	bzero(&hdr, sizeof(hdr));
	hdr.rtm_version = RTM_VERSION;
	hdr.rtm_type = action;
	hdr.rtm_priority = kr_state.fib_prio;
	hdr.rtm_tableid = kr_state.rdomain;	/* rtableid */
	if (action == RTM_CHANGE)
		hdr.rtm_fmask = RTF_REJECT|RTF_BLACKHOLE;
	else
		hdr.rtm_flags = RTF_MPATH;
	hdr.rtm_seq = kr_state.rtseq++;	/* overflow doesn't matter */
	hdr.rtm_hdrlen = sizeof(hdr);
	hdr.rtm_msglen = sizeof(hdr);
	/* adjust iovec */
	iov[iovcnt].iov_base = &hdr;
	iov[iovcnt++].iov_len = sizeof(hdr);

	bzero(&prefix, sizeof(prefix));
	prefix.addr.sin6_len = sizeof(struct sockaddr_in6);
	prefix.addr.sin6_family = AF_INET6;
	prefix.addr.sin6_addr = kroute->prefix;
	/* adjust header */
	hdr.rtm_addrs |= RTA_DST;
	hdr.rtm_msglen += ROUNDUP(sizeof(struct sockaddr_in6));
	/* adjust iovec */
	iov[iovcnt].iov_base = &prefix;
	iov[iovcnt++].iov_len = ROUNDUP(sizeof(struct sockaddr_in6));

	if (!IN6_IS_ADDR_UNSPECIFIED(&kroute->nexthop)) {
		bzero(&nexthop, sizeof(nexthop));
		nexthop.addr.sin6_len = sizeof(struct sockaddr_in6);
		nexthop.addr.sin6_family = AF_INET6;
		nexthop.addr.sin6_addr = kroute->nexthop;
		nexthop.addr.sin6_scope_id = kroute->scope;
		/*
		 * XXX we should set the sin6_scope_id but the kernel
		 * XXX does not expect it that way. It must be fiddled
		 * XXX into the sin6_addr. Welcome to the typical
		 * XXX IPv6 insanity and all without wine bottles.
		 */
		embedscope(&nexthop.addr);

		/* adjust header */
		hdr.rtm_flags |= RTF_GATEWAY;
		hdr.rtm_addrs |= RTA_GATEWAY;
		hdr.rtm_msglen += ROUNDUP(sizeof(struct sockaddr_in6));
		/* adjust iovec */
		iov[iovcnt].iov_base = &nexthop;
		iov[iovcnt++].iov_len = ROUNDUP(sizeof(struct sockaddr_in6));
	} else if (kroute->ifindex) {
		/*
		 * We don't have an interface address in that network,
		 * so we install a cloning route.  The kernel will then
		 * do neighbor discovery.
		 */
		bzero(&ifp, sizeof(ifp));
		ifp.addr.sdl_len = sizeof(struct sockaddr_dl);
		ifp.addr.sdl_family = AF_LINK;

		ifp.addr.sdl_index  = kroute->ifindex;
		/* adjust header */
		hdr.rtm_flags |= RTF_CLONING;
		hdr.rtm_addrs |= RTA_GATEWAY;
		hdr.rtm_msglen += ROUNDUP(sizeof(struct sockaddr_dl));
		/* adjust iovec */
		iov[iovcnt].iov_base = &ifp;
		iov[iovcnt++].iov_len = ROUNDUP(sizeof(struct sockaddr_dl));
	}

	bzero(&mask, sizeof(mask));
	mask.addr.sin6_len = sizeof(struct sockaddr_in6);
	mask.addr.sin6_family = AF_INET6;
	mask.addr.sin6_addr = *prefixlen2mask(kroute->prefixlen);
	/* adjust header */
	if (kroute->prefixlen == 128)
		hdr.rtm_flags |= RTF_HOST;
	hdr.rtm_addrs |= RTA_NETMASK;
	hdr.rtm_msglen += ROUNDUP(sizeof(struct sockaddr_in6));
	/* adjust iovec */
	iov[iovcnt].iov_base = &mask;
	iov[iovcnt++].iov_len = ROUNDUP(sizeof(struct sockaddr_in6));

	if (kroute->rtlabel != 0) {
		sa_rl.sr_len = sizeof(sa_rl);
		sa_rl.sr_family = AF_UNSPEC;
		label = rtlabel_id2name(kroute->rtlabel);
		if (strlcpy(sa_rl.sr_label, label,
		    sizeof(sa_rl.sr_label)) >= sizeof(sa_rl.sr_label)) {
			log_warnx("send_rtmsg: invalid rtlabel");
			return (-1);
		}
		/* adjust header */
		hdr.rtm_addrs |= RTA_LABEL;
		hdr.rtm_msglen += sizeof(sa_rl);
		/* adjust iovec */
		iov[iovcnt].iov_base = &sa_rl;
		iov[iovcnt++].iov_len = sizeof(sa_rl);
	}

retry:
	if (writev(fd, iov, iovcnt) == -1) {
		if (errno == ESRCH) {
			if (hdr.rtm_type == RTM_CHANGE) {
				hdr.rtm_type = RTM_ADD;
				goto retry;
			} else if (hdr.rtm_type == RTM_DELETE) {
				log_info("route %s/%u vanished before delete",
				    log_sockaddr(&prefix), kroute->prefixlen);
				return (0);
			}
		}
		log_warn("send_rtmsg: action %u, prefix %s/%u", hdr.rtm_type,
		    log_sockaddr(&prefix), kroute->prefixlen);
		return (0);
	}

	return (0);
}

int
fetchtable(void)
{
	size_t			 len;
	int			 mib[7];
	char			*buf;
	int			 rv;

	mib[0] = CTL_NET;
	mib[1] = PF_ROUTE;
	mib[2] = 0;
	mib[3] = AF_INET6;
	mib[4] = NET_RT_DUMP;
	mib[5] = 0;
	mib[6] = kr_state.rdomain;	/* rtableid */

	if (sysctl(mib, 7, NULL, &len, NULL, 0) == -1) {
		log_warn("sysctl");
		return (-1);
	}
	if ((buf = malloc(len)) == NULL) {
		log_warn("fetchtable");
		return (-1);
	}
	if (sysctl(mib, 7, buf, &len, NULL, 0) == -1) {
		log_warn("sysctl");
		free(buf);
		return (-1);
	}

	rv = rtmsg_process(buf, len);
	free(buf);

	return (rv);
}

int
fetchifs(u_short ifindex)
{
	size_t			 len;
	int			 mib[6];
	char			*buf;
	int			 rv;

	mib[0] = CTL_NET;
	mib[1] = PF_ROUTE;
	mib[2] = 0;
	mib[3] = AF_INET6;
	mib[4] = NET_RT_IFLIST;
	mib[5] = ifindex;

	if (sysctl(mib, 6, NULL, &len, NULL, 0) == -1) {
		log_warn("sysctl");
		return (-1);
	}
	if ((buf = malloc(len)) == NULL) {
		log_warn("fetchifs");
		return (-1);
	}
	if (sysctl(mib, 6, buf, &len, NULL, 0) == -1) {
		log_warn("sysctl");
		free(buf);
		return (-1);
	}

	rv = rtmsg_process(buf, len);
	free(buf);

	return (rv);
}

int
dispatch_rtmsg(void)
{
	char			 buf[RT_BUF_SIZE];
	ssize_t			 n;

	if ((n = read(kr_state.fd, &buf, sizeof(buf))) == -1) {
		if (errno == EAGAIN || errno == EINTR)
			return (0);
		log_warn("dispatch_rtmsg: read error");
		return (-1);
	}

	if (n == 0) {
		log_warnx("routing socket closed");
		return (-1);
	}

	return (rtmsg_process(buf, n));
}

int
rtmsg_process(char *buf, size_t len)
{
	struct rt_msghdr	*rtm;
	struct if_msghdr	 ifm;
	struct ifa_msghdr	*ifam;
	struct sockaddr		*sa, *rti_info[RTAX_MAX];
	struct sockaddr_in6	*sa_in6;
	struct sockaddr_rtlabel	*label;
	struct kroute_node	*kr, *okr;
	struct in6_addr		 prefix, nexthop;
	u_int8_t		 prefixlen, prio;
	int			 flags, mpath;
	unsigned int		 scope;
	u_short			 ifindex = 0;
	int			 rv, delay;
	size_t			 offset;
	char			*next;

	for (offset = 0; offset < len; offset += rtm->rtm_msglen) {
		next = buf + offset;
		rtm = (struct rt_msghdr *)next;
		if (len < offset + sizeof(u_short) ||
		    len < offset + rtm->rtm_msglen)
			fatalx("rtmsg_process: partial rtm in buffer");
		if (rtm->rtm_version != RTM_VERSION)
			continue;

		bzero(&prefix, sizeof(prefix));
		bzero(&nexthop, sizeof(nexthop));
		scope = 0;
		prefixlen = 0;
		flags = F_KERNEL;
		mpath = 0;
		prio = 0;

		sa = (struct sockaddr *)(next + rtm->rtm_hdrlen);
		get_rtaddrs(rtm->rtm_addrs, sa, rti_info);

		switch (rtm->rtm_type) {
		case RTM_ADD:
		case RTM_GET:
		case RTM_CHANGE:
		case RTM_DELETE:
			if (rtm->rtm_errno)		/* failed attempts... */
				continue;

			if (rtm->rtm_tableid != kr_state.rdomain)
				continue;

			if (rtm->rtm_type == RTM_GET &&
			    rtm->rtm_pid != kr_state.pid) /* caused by us */
				continue;

			if ((sa = rti_info[RTAX_DST]) == NULL)
				continue;

			/* Skip ARP/ND cache and broadcast routes. */
			if (rtm->rtm_flags & (RTF_LLINFO|RTF_BROADCAST))
				continue;

			if (rtm->rtm_flags & RTF_MPATH)
				mpath = 1;
			prio = rtm->rtm_priority;
			flags = (prio == kr_state.fib_prio) ?
			    F_OSPFD_INSERTED : F_KERNEL;

			switch (sa->sa_family) {
			case AF_INET6:
				prefix =
				    ((struct sockaddr_in6 *)sa)->sin6_addr;
				sa_in6 = (struct sockaddr_in6 *)
				    rti_info[RTAX_NETMASK];
				if (sa_in6 != NULL) {
					if (sa_in6->sin6_len != 0)
						prefixlen = mask2prefixlen(
						    sa_in6);
				} else if (rtm->rtm_flags & RTF_HOST)
					prefixlen = 128;
				else
					fatalx("classful IPv6 address?!!");
				if (rtm->rtm_flags & RTF_STATIC)
					flags |= F_STATIC;
				if (rtm->rtm_flags & RTF_BLACKHOLE)
					flags |= F_BLACKHOLE;
				if (rtm->rtm_flags & RTF_REJECT)
					flags |= F_REJECT;
				if (rtm->rtm_flags & RTF_DYNAMIC)
					flags |= F_DYNAMIC;
				break;
			default:
				continue;
			}

			ifindex = rtm->rtm_index;
			if ((sa = rti_info[RTAX_GATEWAY]) != NULL) {
				switch (sa->sa_family) {
				case AF_INET6:
					if (rtm->rtm_flags & RTF_CONNECTED)
						flags |= F_CONNECTED;

					sa_in6 = (struct sockaddr_in6 *)sa;
					/*
					 * XXX The kernel provides the scope
					 * XXX via the kame hack instead of
					 * XXX the scope_id field.
					 */
					recoverscope(sa_in6);
					nexthop = sa_in6->sin6_addr;
					scope = sa_in6->sin6_scope_id;
					break;
				case AF_LINK:
					flags |= F_CONNECTED;
					break;
				}
			}
		}

		switch (rtm->rtm_type) {
		case RTM_ADD:
		case RTM_GET:
		case RTM_CHANGE:
			if (IN6_IS_ADDR_UNSPECIFIED(&nexthop) &&
			    !(flags & F_CONNECTED)) {
				log_warnx("rtmsg_process no nexthop for %s/%u",
				    log_in6addr(&prefix), prefixlen);
				continue;
			}

			if ((okr = kroute_find(&prefix, prefixlen, prio))
			    != NULL) {
				kr = okr;
				if ((mpath || prio == kr_state.fib_prio) &&
				    (kr = kroute_matchgw(okr, &nexthop, scope)) ==
				    NULL) {
					log_warnx("rtmsg_process: mpath route"
					    " not found");
					/* add routes we missed out earlier */
					goto add;
				}

				if (kr->r.flags & F_REDISTRIBUTED)
					flags |= F_REDISTRIBUTED;
				kr->r.nexthop = nexthop;
				kr->r.scope = scope;
				kr->r.flags = flags;
				kr->r.ifindex = ifindex;

				rtlabel_unref(kr->r.rtlabel);
				kr->r.rtlabel = 0;
				kr->r.ext_tag = 0;
				if ((label = (struct sockaddr_rtlabel *)
				    rti_info[RTAX_LABEL]) != NULL) {
					kr->r.rtlabel =
					    rtlabel_name2id(label->sr_label);
					kr->r.ext_tag =
					    rtlabel_id2tag(kr->r.rtlabel);
				}

				if (kif_validate(kr->r.ifindex))
					kr->r.flags &= ~F_DOWN;
				else
					kr->r.flags |= F_DOWN;

				/* just readd, the RDE will care */
				kr->serial = kr_state.fib_serial;
				kr_redistribute(kr);
			} else {
add:
				if ((kr = calloc(1,
				    sizeof(struct kroute_node))) == NULL) {
					log_warn("rtmsg_process calloc");
					return (-1);
				}
				kr->r.prefix = prefix;
				kr->r.prefixlen = prefixlen;
				kr->r.nexthop = nexthop;
				kr->r.scope = scope;
				kr->r.flags = flags;
				kr->r.ifindex = ifindex;
				kr->r.priority = prio;

				if (rtm->rtm_priority == kr_state.fib_prio) {
					log_warnx("alien OSPF route %s/%d",
					    log_in6addr(&prefix), prefixlen);
					rv = send_rtmsg(kr_state.fd,
					    RTM_DELETE, &kr->r);
					free(kr);
					if (rv == -1)
						return (-1);
				} else {
					if ((label = (struct sockaddr_rtlabel *)
					    rti_info[RTAX_LABEL]) != NULL) {
						kr->r.rtlabel =
						    rtlabel_name2id(
						    label->sr_label);
						kr->r.ext_tag =
						    rtlabel_id2tag(
						    kr->r.rtlabel);
					}

					kroute_insert(kr);
				}
			}
			break;
		case RTM_DELETE:
			if ((kr = kroute_find(&prefix, prefixlen, prio)) ==
			    NULL)
				continue;
			if (!(kr->r.flags & F_KERNEL))
				continue;
			/* get the correct route */
			okr = kr;
			if (mpath && (kr = kroute_matchgw(kr, &nexthop,
			    scope)) == NULL) {
				log_warnx("rtmsg_process mpath route"
				    " not found");
				return (-1);
			}
			if (kroute_remove(kr) == -1)
				return (-1);
			break;
		case RTM_IFINFO:
			memcpy(&ifm, next, sizeof(ifm));
			if_change(ifm.ifm_index, ifm.ifm_flags, &ifm.ifm_data,
			    (struct sockaddr_dl *)rti_info[RTAX_IFP]);
			break;
		case RTM_NEWADDR:
			ifam = (struct ifa_msghdr *)rtm;
			if ((ifam->ifam_addrs & (RTA_NETMASK | RTA_IFA |
			    RTA_BRD)) == 0)
				break;

			if_newaddr(ifam->ifam_index,
			    (struct sockaddr_in6 *)rti_info[RTAX_IFA],
			    (struct sockaddr_in6 *)rti_info[RTAX_NETMASK],
			    (struct sockaddr_in6 *)rti_info[RTAX_BRD]);
			break;
		case RTM_DELADDR:
			ifam = (struct ifa_msghdr *)rtm;
			if ((ifam->ifam_addrs & (RTA_NETMASK | RTA_IFA |
			    RTA_BRD)) == 0)
				break;

			if_deladdr(ifam->ifam_index,
			    (struct sockaddr_in6 *)rti_info[RTAX_IFA],
			    (struct sockaddr_in6 *)rti_info[RTAX_NETMASK],
			    (struct sockaddr_in6 *)rti_info[RTAX_BRD]);
			break;
		case RTM_IFANNOUNCE:
			if_announce(next);
			break;
		case RTM_DESYNC:
			/*
			 * We lost some routing packets. Schedule a reload
			 * of the kernel route/interface information.
			 */
			if (kr_state.reload_state == KR_RELOAD_IDLE) {
				delay = KR_RELOAD_TIMER;
				log_info("desync; scheduling fib reload");
			} else {
				delay = KR_RELOAD_HOLD_TIMER;
				log_debug("desync during KR_RELOAD_%s",
				    kr_state.reload_state ==
				    KR_RELOAD_FETCH ? "FETCH" : "HOLD");
			}
			kr_state.reload_state = KR_RELOAD_FETCH;
			kr_fib_reload_arm_timer(delay);
			break;
		default:
			/* ignore for now */
			break;
		}
	}
	return (offset);
}