path: root/usr.sbin/snmpd/kroute.c

/*	$OpenBSD: kroute.c,v 1.20 2012/09/17 16:43:59 reyk Exp $	*/

/*
 * Copyright (c) 2007, 2008 Reyk Floeter <reyk@openbsd.org>
 * 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/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/tree.h>
#include <sys/uio.h>
#include <sys/ioctl.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <event.h>

#include "snmpd.h"

extern struct snmpd	*env;

struct {
	struct event		 ks_ev;
	u_long			 ks_iflastchange;
	u_long			 ks_nroutes;	/* 4 billions enough? */
	int			 ks_fd;
	int			 ks_ifd;
	u_short			 ks_nkif;
} kr_state;

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

struct kroute6_node {
	RB_ENTRY(kroute6_node)	 entry;
	struct kroute6		 r;
	struct kroute6_node	*next;
};

struct kif_node {
	RB_ENTRY(kif_node)	 entry;
	TAILQ_HEAD(, kif_addr)	 addrs;
	struct kif		 k;
};

int	kroute_compare(struct kroute_node *, struct kroute_node *);
int	kroute6_compare(struct kroute6_node *, struct kroute6_node *);
int	kif_compare(struct kif_node *, struct kif_node *);

struct kroute_node	*kroute_find(in_addr_t, u_int8_t, u_int8_t);
struct kroute_node	*kroute_matchgw(struct kroute_node *,
			    struct sockaddr_in *);
int			 kroute_insert(struct kroute_node *);
int			 kroute_remove(struct kroute_node *);
void			 kroute_clear(void);

struct kroute6_node	*kroute6_find(const struct in6_addr *, u_int8_t,
			     u_int8_t);
struct kroute6_node	*kroute6_matchgw(struct kroute6_node *,
			    struct sockaddr_in6 *);
int			 kroute6_insert(struct kroute6_node *);
int			 kroute6_remove(struct kroute6_node *);
void			 kroute6_clear(void);

struct kif_node		*kif_find(u_short);
struct kif_node		*kif_insert(u_short);
int			 kif_remove(struct kif_node *);
void			 kif_clear(void);
struct kif		*kif_update(u_short, int, struct if_data *,
			    struct sockaddr_dl *);

int			 ka_compare(struct kif_addr *, struct kif_addr *);
void			 ka_insert(u_short, struct kif_addr *);
struct kif_addr		*ka_find(struct sockaddr *);
int			 ka_remove(struct kif_addr *);

u_int8_t	prefixlen_classful(in_addr_t);
u_int8_t	mask2prefixlen(in_addr_t);
in_addr_t	prefixlen2mask(u_int8_t);
u_int8_t	mask2prefixlen6(struct sockaddr_in6 *);
struct in6_addr *prefixlen2mask6(u_int8_t);
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 *, struct sockaddr *,
		    struct sockaddr *);
void		if_deladdr(u_short, struct sockaddr *, struct sockaddr *,
		    struct sockaddr *);
void		if_announce(void *);

int		fetchtable(void);
int		fetchifs(u_short);
void		dispatch_rtmsg(int, short, void *);
int		rtmsg_process(char *, int);
int		dispatch_rtmsg_addr(struct rt_msghdr *,
		    struct sockaddr *[RTAX_MAX]);

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)

RB_HEAD(kroute6_tree, kroute6_node)	krt6;
RB_PROTOTYPE(kroute6_tree, kroute6_node, entry, kroute6_compare)
RB_GENERATE(kroute6_tree, kroute6_node, entry, kroute6_compare)

RB_HEAD(kif_tree, kif_node)		kit;
RB_PROTOTYPE(kif_tree, kif_node, entry, kif_compare)
RB_GENERATE(kif_tree, kif_node, entry, kif_compare)

RB_HEAD(ka_tree, kif_addr)		kat;
RB_PROTOTYPE(ka_tree, kif_addr, node, ka_compare)
RB_GENERATE(ka_tree, kif_addr, node, ka_compare)

void
kr_init(void)
{
	int		opt = 0, rcvbuf, default_rcvbuf;
	socklen_t	optlen;

	if ((kr_state.ks_ifd = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
		fatal("kr_init: ioctl socket");

	if ((kr_state.ks_fd = socket(AF_ROUTE, SOCK_RAW, 0)) == -1) 
		fatal("kr_init: route socket");

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

	if (env->sc_rtfilter && setsockopt(kr_state.ks_fd, PF_ROUTE,
	    ROUTE_MSGFILTER, &env->sc_rtfilter, sizeof(env->sc_rtfilter)) == -1)
		log_warn("kr_init: setsockopt(ROUTE_MSGFILTER)");

	/* grow receive buffer, don't wanna miss messages */
	optlen = sizeof(default_rcvbuf);
	if (getsockopt(kr_state.ks_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.ks_fd, SOL_SOCKET, SO_RCVBUF,
		    &rcvbuf, sizeof(rcvbuf)) == -1 && errno == ENOBUFS;
		    rcvbuf /= 2)
			;	/* nothing */

	RB_INIT(&krt);
	RB_INIT(&krt6);
	RB_INIT(&kit);
	RB_INIT(&kat);

	if (fetchifs(0) == -1)
		fatalx("kr_init fetchifs");
	if (fetchtable() == -1)
		fatalx("kr_init fetchtable");

	event_set(&kr_state.ks_ev, kr_state.ks_fd, EV_READ | EV_PERSIST,
	    dispatch_rtmsg, NULL);
	event_add(&kr_state.ks_ev, NULL);
}

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

u_int
kr_ifnumber(void)
{
	return (kr_state.ks_nkif);
}

u_long
kr_iflastchange(void)
{
	return (kr_state.ks_iflastchange);
}

int
kr_updateif(u_int if_index)
{
	struct kif_node	*kn;

	if ((kn = kif_find(if_index)) != NULL)
		kif_remove(kn);

	/* Do not update the interface address list */
	return (fetchifs(if_index));
}

u_long
kr_routenumber(void)
{
	return (kr_state.ks_nroutes);
}

/* rb-tree compare */
int
kroute_compare(struct kroute_node *a, struct kroute_node *b)
{
	if (ntohl(a->r.prefix.s_addr) < ntohl(b->r.prefix.s_addr))
		return (-1);
	if (ntohl(a->r.prefix.s_addr) > ntohl(b->r.prefix.s_addr))
		return (1);
	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);
}

int
kroute6_compare(struct kroute6_node *a, struct kroute6_node *b)
{
	int i;

	for (i = 0; i < 16; i++) {
		if (a->r.prefix.s6_addr[i] < b->r.prefix.s6_addr[i])
			return (-1);
		if (a->r.prefix.s6_addr[i] > b->r.prefix.s6_addr[i])
			return (1);
	}

	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);
}

int
kif_compare(struct kif_node *a, struct kif_node *b)
{
	return (a->k.if_index - b->k.if_index);
}

int
ka_compare(struct kif_addr *a, struct kif_addr *b)
{
	if (a->addr.sa.sa_family < b->addr.sa.sa_family)
		return (-1);
	if (a->addr.sa.sa_family > b->addr.sa.sa_family)
		return (1);
	return (memcmp(&a->addr.sa, &b->addr.sa, a->addr.sa.sa_len));
}

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

	s.r.prefix.s_addr = 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 sockaddr_in *sa_in)
{
	in_addr_t	nexthop;

	if (sa_in == NULL) {
		log_warnx("kroute_matchgw: no nexthop defined");
		return (NULL);
	}
	nexthop = sa_in->sin_addr.s_addr;

	while (kr) {
		if (kr->r.nexthop.s_addr == nexthop)
			return (kr);
		kr = kr->next;
	}

	return (NULL);
}

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

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

	kr_state.ks_nroutes++;
	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",
		    inet_ntoa(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",
			    inet_ntoa(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",
				    inet_ntoa(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", inet_ntoa(kr->r.prefix),
			    kr->r.prefixlen);
			return (-1);
		}
		krm->next = kr->next;
	}

	kr_state.ks_nroutes--;
	free(kr);
	return (0);
}

void
kroute_clear(void)
{
	struct kroute_node	*kr;

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

struct kroute6_node *
kroute6_find(const struct in6_addr *prefix, u_int8_t prefixlen, u_int8_t prio)
{
	struct kroute6_node	s;
	struct kroute6_node	*kn6, *tmp;

	memcpy(&s.r.prefix, prefix, sizeof(struct in6_addr));
	s.r.prefixlen = prefixlen;
	s.r.priority = prio;

	kn6 = RB_FIND(kroute6_tree, &krt6, &s);
	if (kn6 && prio == RTP_ANY) {
		tmp = RB_PREV(kroute6_tree, &krt6, kn6);
		while (tmp) {
			if (kroute6_compare(&s, tmp) == 0)
				kn6 = tmp;
			else 
				break;
			tmp = RB_PREV(kroute6_tree, &krt6, kn6);
		}
	}
	return (kn6);
}

struct kroute6_node *
kroute6_matchgw(struct kroute6_node *kr, struct sockaddr_in6 *sa_in6)
{
	struct in6_addr	nexthop;

	if (sa_in6 == NULL) {
		log_warnx("kroute6_matchgw: no nexthop defined");
		return (NULL);
	}
	memcpy(&nexthop, &sa_in6->sin6_addr, sizeof(nexthop));

	while (kr) {
		if (memcmp(&kr->r.nexthop, &nexthop, sizeof(nexthop)) == 0)
			return (kr);
		kr = kr->next;
	}

	return (NULL);
}

int
kroute6_insert(struct kroute6_node *kr)
{
	struct kroute6_node	*krm;

	if ((krm = RB_INSERT(kroute6_tree, &krt6, kr)) != NULL) {
		/* multipath route, add at end of list */
		while (krm->next != NULL)
			krm = krm->next;
		krm->next = kr;
		kr->next = NULL; /* to be sure */
	}

	kr_state.ks_nroutes++;
	return (0);
}

int
kroute6_remove(struct kroute6_node *kr)
{
	struct kroute6_node	*krm;

	if ((krm = RB_FIND(kroute6_tree, &krt6, kr)) == NULL) {
		log_warnx("kroute6_remove failed for %s/%u",
		    log_in6addr(&kr->r.prefix), kr->r.prefixlen);
		return (-1);
	}

	if (krm == kr) {
		/* head element */
		if (RB_REMOVE(kroute6_tree, &krt6, kr) == NULL) {
			log_warnx("kroute6_remove failed for %s/%u",
			    log_in6addr(&kr->r.prefix), kr->r.prefixlen);
			return (-1);
		}
	       	if (kr->next != NULL) {
			if (RB_INSERT(kroute6_tree, &krt6, kr->next) != NULL) {
				log_warnx("kroute6_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("kroute6_remove multipath list corrupted "
			    "for %s/%u", log_in6addr(&kr->r.prefix),
			    kr->r.prefixlen);
			return (-1);
		}
		krm->next = kr->next;
	}

	kr_state.ks_nroutes--;
	free(kr);
	return (0);
}

void
kroute6_clear(void)
{
	struct kroute6_node	*kr;

	while ((kr = RB_MIN(kroute6_tree, &krt6)) != NULL)
		kroute6_remove(kr);
}

struct kif_node *
kif_find(u_short if_index)
{
	struct kif_node	s;

	if (if_index == 0)
		return (RB_MIN(kif_tree, &kit));

	bzero(&s, sizeof(s));
	s.k.if_index = if_index;

	return (RB_FIND(kif_tree, &kit, &s));
}

struct kif *
kr_getif(u_short if_index)
{
	struct kif_node	*kn;

	kn = kif_find(if_index);
	if (kn == NULL)
		return (NULL);

	return (&kn->k);
}

struct kif *
kr_getnextif(u_short if_index)
{
	struct kif_node	*kn;

	if ((kn = kif_find(if_index)) == NULL)
		return (NULL);
	if (if_index)
		kn = RB_NEXT(kif_tree, &kit, kn);
	if (kn == NULL)
		return (NULL);

	return (&kn->k);
}

struct kif_node *
kif_insert(u_short if_index)
{
	struct kif_node	*kif;

	if ((kif = calloc(1, sizeof(struct kif_node))) == NULL)
		return (NULL);

	kif->k.if_index = if_index;
	TAILQ_INIT(&kif->addrs);

	if (RB_INSERT(kif_tree, &kit, kif) != NULL)
		fatalx("kif_insert: RB_INSERT");

	kr_state.ks_nkif++;
	kr_state.ks_iflastchange = smi_getticks();

	return (kif);
}

int
kif_remove(struct kif_node *kif)
{
	struct kif_addr	*ka;

	if (RB_REMOVE(kif_tree, &kit, kif) == NULL) {
		log_warnx("RB_REMOVE(kif_tree, &kit, kif)");
		return (-1);
	}

	while ((ka = TAILQ_FIRST(&kif->addrs)) != NULL) {
		TAILQ_REMOVE(&kif->addrs, ka, entry);
		ka_remove(ka);
	}
	free(kif);

	kr_state.ks_nkif--;
	kr_state.ks_iflastchange = smi_getticks();

	return (0);
}

void
kif_clear(void)
{
	struct kif_node	*kif;

	while ((kif = RB_MIN(kif_tree, &kit)) != NULL)
		kif_remove(kif);
	kr_state.ks_nkif = 0;
	kr_state.ks_iflastchange = smi_getticks();
}

struct kif *
kif_update(u_short if_index, int flags, struct if_data *ifd,
    struct sockaddr_dl *sdl)
{
	struct kif_node		*kif;
	struct ether_addr	*ea;
	struct ifreq		 ifr;

	if ((kif = kif_find(if_index)) == NULL)
		if ((kif = kif_insert(if_index)) == NULL)
			return (NULL);

	kif->k.if_flags = flags;
	bcopy(ifd, &kif->k.if_data, sizeof(struct if_data));
	kif->k.if_ticks = smi_getticks();

	if (sdl && sdl->sdl_family == AF_LINK) {
		if (sdl->sdl_nlen >= sizeof(kif->k.if_name))
			memcpy(kif->k.if_name, sdl->sdl_data,
			    sizeof(kif->k.if_name) - 1);
		else if (sdl->sdl_nlen > 0)
			memcpy(kif->k.if_name, sdl->sdl_data,
			    sdl->sdl_nlen);
		/* string already terminated via calloc() */

		if ((ea = (struct ether_addr *)LLADDR(sdl)) != NULL)
			bcopy(&ea->ether_addr_octet, kif->k.if_lladdr,
			    ETHER_ADDR_LEN);
	}

	bzero(&ifr, sizeof(ifr));
	strlcpy(ifr.ifr_name, kif->k.if_name, sizeof(ifr.ifr_name));
	ifr.ifr_data = (caddr_t)&kif->k.if_descr;
	if (ioctl(kr_state.ks_ifd, SIOCGIFDESCR, &ifr) == -1)
		bzero(&kif->k.if_descr, sizeof(kif->k.if_descr));

	return (&kif->k);
}

void
ka_insert(u_short if_index, struct kif_addr *ka)
{
	if (ka->addr.sa.sa_len == 0)
		return;

	ka->if_index = if_index;
	RB_INSERT(ka_tree, &kat, ka);
}

struct kif_addr	*
ka_find(struct sockaddr *sa)
{
	struct kif_addr		ka;

	if (sa == NULL)
		return (RB_MIN(ka_tree, &kat));
	bzero(&ka.addr, sizeof(ka.addr));
	bcopy(sa, &ka.addr.sa, sa->sa_len);
	return (RB_FIND(ka_tree, &kat, &ka));
}

int
ka_remove(struct kif_addr *ka)
{
	RB_REMOVE(ka_tree, &kat, ka);
	free(ka);
	return (0);
}

struct kif_addr *
kr_getaddr(struct sockaddr *sa)
{
	return (ka_find(sa));
}

struct kif_addr *
kr_getnextaddr(struct sockaddr *sa)
{
	struct kif_addr	*ka;

	if ((ka = ka_find(sa)) == NULL)
		return (NULL);
	if (sa)
		ka = RB_NEXT(ka_tree, &kat, ka);

	return (ka);
}

/* misc */
u_int8_t
prefixlen_classful(in_addr_t ina)
{
	/* it hurt to write this. */

	if (ina >= 0xf0000000U)		/* class E */
		return (32);
	else if (ina >= 0xe0000000U)	/* class D */
		return (4);
	else if (ina >= 0xc0000000U)	/* class C */
		return (24);
	else if (ina >= 0x80000000U)	/* class B */
		return (16);
	else				/* class A */
		return (8);
}

u_int8_t
mask2prefixlen(in_addr_t ina)
{
	if (ina == 0)
		return (0);
	else
		return (33 - ffs(ntohl(ina)));
}

in_addr_t
prefixlen2mask(u_int8_t prefixlen)
{
	if (prefixlen == 0)
		return (0);

	return (htonl(0xffffffff << (32 - prefixlen)));
}

u_int8_t
mask2prefixlen6(struct sockaddr_in6 *sa_in6)
{
	u_int8_t	 l = 0, i, len;

	/*
	 * sin6_len is the size of the sockaddr so subtract the offset of
	 * the possibly truncated sin6_addr struct.
	 */
	len = sa_in6->sin6_len -
	    (u_int8_t)(&((struct sockaddr_in6 *)NULL)->sin6_addr);
	for (i = 0; i < len; i++) {
		/* this "beauty" is adopted from sbin/route/show.c ... */
		switch (sa_in6->sin6_addr.s6_addr[i]) {
		case 0xff:
			l += 8;
			break;
		case 0xfe:
			l += 7;
			return (l);
		case 0xfc:
			l += 6;
			return (l);
		case 0xf8:
			l += 5;
			return (l);
		case 0xf0:
			l += 4;
			return (l);
		case 0xe0:
			l += 3;
			return (l);
		case 0xc0:
			l += 2;
			return (l);
		case 0x80:
			l += 1;
			return (l);
		case 0x00:
			return (l);
		default:
			fatalx("non contiguous inet6 netmask");
		}
	}

	return (l);
}

struct in6_addr *
prefixlen2mask6(u_int8_t prefixlen)
{
	static struct in6_addr	mask;
	int			i;

	bzero(&mask, sizeof(mask));
	for (i = 0; i < prefixlen / 8; i++)
		mask.s6_addr[i] = 0xff;
	i = prefixlen % 8;
	if (i)
		mask.s6_addr[prefixlen / 8] = 0xff00 >> i;

	return (&mask);
}

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

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 if_index, int flags, struct if_data *ifd,
    struct sockaddr_dl *sdl)
{
	if (kif_update(if_index, flags, ifd, sdl) == NULL)
		log_warn("if_change:  kif_update(%u)", if_index);
}

void
if_newaddr(u_short if_index, struct sockaddr *ifa, struct sockaddr *mask,
    struct sockaddr *brd)
{
	struct kif_node *kif;
	struct kif_addr *ka;

	if (ifa == NULL)
		return;
	if ((kif = kif_find(if_index)) == NULL) {
		log_warnx("if_newaddr: corresponding if %i not found",
		    if_index);
		return;
	}
	if ((ka = ka_find(ifa)) == NULL) {
		if ((ka = calloc(1, sizeof(struct kif_addr))) == NULL)
			fatal("if_newaddr");
		bcopy(ifa, &ka->addr.sa, ifa->sa_len);
		TAILQ_INSERT_TAIL(&kif->addrs, ka, entry);
		ka_insert(if_index, ka);
	}

	if (mask)
		bcopy(mask, &ka->mask.sa, mask->sa_len);
	else
		bzero(&ka->mask, sizeof(ka->mask));
	if (brd)
		bcopy(brd, &ka->dstbrd.sa, brd->sa_len);
	else
		bzero(&ka->mask, sizeof(ka->mask));

}

void
if_deladdr(u_short if_index, struct sockaddr *ifa, struct sockaddr *mask,
    struct sockaddr *brd)
{
	struct kif_node *kif;
	struct kif_addr *ka;

	if (ifa == NULL)
		return;
	if ((kif = kif_find(if_index)) == NULL) {
		log_warnx("if_deladdr: corresponding if %i not found",
		    if_index);
		return;
	}
	if ((ka = ka_find(ifa)) == NULL)
		return;

	TAILQ_REMOVE(&kif->addrs, ka, entry);
	ka_remove(ka);
}

void
if_announce(void *msg)
{
	struct if_announcemsghdr	*ifan;
	struct kif_node			*kif;

	ifan = msg;

	switch (ifan->ifan_what) {
	case IFAN_ARRIVAL:
		kif = kif_insert(ifan->ifan_index);
		strlcpy(kif->k.if_name, ifan->ifan_name,
		    sizeof(kif->k.if_name));
		break;
	case IFAN_DEPARTURE:
		kif = kif_find(ifan->ifan_index);
		kif_remove(kif);
		break;
	}
}

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

	mib[0] = CTL_NET;
	mib[1] = AF_ROUTE;
	mib[2] = 0;
	mib[3] = AF_INET;
	mib[4] = NET_RT_DUMP;
	mib[5] = 0;
	mib[6] = 0;	/* 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 if_index)
{
	size_t			 len;
	int			 mib[6];
	char			*buf;
	int			 rv;

	mib[0] = CTL_NET;
	mib[1] = AF_ROUTE;
	mib[2] = 0;
	mib[3] = 0;	/* wildcard address family */
	mib[4] = NET_RT_IFLIST;
	mib[5] = if_index;

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

/* ARGSUSED */
void
dispatch_rtmsg(int fd, short event, void *arg)
{
	char			 buf[RT_BUF_SIZE];
	ssize_t			 n;

	if ((n = read(fd, &buf, sizeof(buf))) == -1) {
		log_warn("dispatch_rtmsg: read error");
		return;
	}

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

	rtmsg_process(buf, n);
}

int
rtmsg_process(char *buf, int len)
{
	struct rt_msghdr	*rtm;
	struct if_msghdr	 ifm;
	struct ifa_msghdr	*ifam;
	struct sockaddr		*sa, *rti_info[RTAX_MAX];
	int			 offset;
	char			*next;

	for (offset = 0; offset < len; offset += rtm->rtm_msglen) {
		next = buf + offset;
		rtm = (struct rt_msghdr *)next;
		if (rtm->rtm_version != RTM_VERSION)
			continue;

		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_flags & RTF_LLINFO) /* arp cache */
				continue;

			if (dispatch_rtmsg_addr(rtm, rti_info) == -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_DELADDR:
			ifam = (struct ifa_msghdr *)rtm;
			if ((ifam->ifam_addrs & (RTA_NETMASK | RTA_IFA |
			    RTA_BRD)) == 0)
				break;

			if_deladdr(ifam->ifam_index, rti_info[RTAX_IFA],
			    rti_info[RTAX_NETMASK], rti_info[RTAX_BRD]);
			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, rti_info[RTAX_IFA],
			    rti_info[RTAX_NETMASK], rti_info[RTAX_BRD]);
			break;
		case RTM_IFANNOUNCE:
			if_announce(next);
			break;
		default:
			/* ignore for now */
			break;
		}
	}

	return (offset);
}

int
dispatch_rtmsg_addr(struct rt_msghdr *rtm, struct sockaddr *rti_info[RTAX_MAX])
{
	struct sockaddr		*sa, *psa;
	struct sockaddr_in	*sa_in, *psa_in = NULL;
	struct sockaddr_in6	*sa_in6, *psa_in6 = NULL;
	struct kroute_node	*kr;
	struct kroute6_node	*kr6;
	int			 flags, mpath = 0;
	u_int16_t		 ifindex;
	u_int8_t		 prefixlen;
	u_int8_t		 prio;

	flags = 0;
	ifindex = 0;
	prefixlen = 0;

	if ((psa = rti_info[RTAX_DST]) == NULL)
		return (-1);

	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;
#ifdef RTF_MPATH
	if (rtm->rtm_flags & RTF_MPATH)
		mpath = 1;
#endif

	prio = rtm->rtm_priority;
	switch (psa->sa_family) {
	case AF_INET:
		psa_in = (struct sockaddr_in *)psa;
		sa_in = (struct sockaddr_in *)rti_info[RTAX_NETMASK];
		if (sa_in != NULL) {
			if (sa_in->sin_len != 0)
				prefixlen = mask2prefixlen(
				    sa_in->sin_addr.s_addr);
		} else if (rtm->rtm_flags & RTF_HOST)
			prefixlen = 32;
		else
			prefixlen =
			    prefixlen_classful(psa_in->sin_addr.s_addr);
		break;
	case AF_INET6:
		psa_in6 = (struct sockaddr_in6 *)psa;
		sa_in6 = (struct sockaddr_in6 *)rti_info[RTAX_NETMASK];
		if (sa_in6 != NULL) {
			if (sa_in6->sin6_len != 0)
				prefixlen = mask2prefixlen6(sa_in6);
		} else if (rtm->rtm_flags & RTF_HOST)
			prefixlen = 128;
		else
			fatalx("in6 net addr without netmask");
		break;
	default:
		return (0);
	}

	if ((sa = rti_info[RTAX_GATEWAY]) != NULL)
		switch (sa->sa_family) {
		case AF_LINK:
			flags |= F_CONNECTED;
			ifindex = rtm->rtm_index;
			sa = NULL;
			mpath = 0;	/* link local stuff can't be mpath */
			break;
		}

	if (rtm->rtm_type == RTM_DELETE) {
		switch (psa->sa_family) {
		case AF_INET:
			sa_in = (struct sockaddr_in *)sa;
			if ((kr = kroute_find(psa_in->sin_addr.s_addr,
			    prefixlen, prio)) == NULL)
				return (0);

			if (mpath)
				/* get the correct route */
				if ((kr = kroute_matchgw(kr, sa_in)) == NULL) {
					log_warnx("dispatch_rtmsg[delete] "
					    "mpath route not found");
					return (0);
				}

			if (kroute_remove(kr) == -1)
				return (-1);
			break;
		case AF_INET6:
			sa_in6 = (struct sockaddr_in6 *)sa;
			if ((kr6 = kroute6_find(&psa_in6->sin6_addr, prefixlen,
			    prio)) == NULL)
				return (0);

			if (mpath)
				/* get the correct route */
				if ((kr6 = kroute6_matchgw(kr6, sa_in6)) ==
				    NULL) {
					log_warnx("dispatch_rtmsg[delete] "
					    "IPv6 mpath route not found");
					return (0);
				}

			if (kroute6_remove(kr6) == -1)
				return (-1);
			break;
		}
		return (0);
	}

	if (sa == NULL && !(flags & F_CONNECTED))
		return (0);

	switch (psa->sa_family) {
	case AF_INET:
		sa_in = (struct sockaddr_in *)sa;
		if ((kr = kroute_find(psa_in->sin_addr.s_addr, prefixlen,
		    prio)) != NULL) {
			/* get the correct route */
			if (mpath && rtm->rtm_type == RTM_CHANGE &&
			    (kr = kroute_matchgw(kr, sa_in)) == NULL) {
				log_warnx("dispatch_rtmsg[change] "
				    "mpath route not found");
				return (-1);
			} else if (mpath && rtm->rtm_type == RTM_ADD)
				goto add4;

			if (sa_in != NULL)
				kr->r.nexthop.s_addr =
				    sa_in->sin_addr.s_addr;
			else
				kr->r.nexthop.s_addr = 0;
			kr->r.flags = flags;
			kr->r.if_index = ifindex;
			kr->r.ticks = smi_getticks();
		} else {
add4:
			if ((kr = calloc(1,
			    sizeof(struct kroute_node))) == NULL) {
				log_warn("dispatch_rtmsg");
				return (-1);
			}
			kr->r.prefix.s_addr = psa_in->sin_addr.s_addr;
			kr->r.prefixlen = prefixlen;
			if (sa_in != NULL)
				kr->r.nexthop.s_addr = sa_in->sin_addr.s_addr;
			else
				kr->r.nexthop.s_addr = 0;
			kr->r.flags = flags;
			kr->r.if_index = ifindex;
			kr->r.ticks = smi_getticks();
			kr->r.priority = prio;

			kroute_insert(kr);
		}
		break;
	case AF_INET6:
		sa_in6 = (struct sockaddr_in6 *)sa;
		if ((kr6 = kroute6_find(&psa_in6->sin6_addr, prefixlen,
		    prio)) != NULL) {
			/* get the correct route */
			if (mpath && rtm->rtm_type == RTM_CHANGE &&
			    (kr6 = kroute6_matchgw(kr6, sa_in6)) ==
			    NULL) {
				log_warnx("dispatch_rtmsg[change] "
				    "mpath route not found");
				return (-1);
			} else if (mpath && rtm->rtm_type == RTM_ADD)
				goto add6;

			if (sa_in6 != NULL)
				memcpy(&kr6->r.nexthop,
				    &sa_in6->sin6_addr,
				    sizeof(struct in6_addr));
			else
				memcpy(&kr6->r.nexthop,
				    &in6addr_any,
				    sizeof(struct in6_addr));

			kr6->r.flags = flags;
			kr6->r.if_index = ifindex;
			kr6->r.ticks = smi_getticks();
		} else {
add6:
			if ((kr6 = calloc(1,
			    sizeof(struct kroute6_node))) == NULL) {
				log_warn("dispatch_rtmsg");
				return (-1);
			}
			memcpy(&kr6->r.prefix, &psa_in6->sin6_addr,
			    sizeof(struct in6_addr));
			kr6->r.prefixlen = prefixlen;
			if (sa_in6 != NULL)
				memcpy(&kr6->r.nexthop, &sa_in6->sin6_addr,
				    sizeof(struct in6_addr));
			else
				memcpy(&kr6->r.nexthop, &in6addr_any,
				    sizeof(struct in6_addr));
			kr6->r.flags = flags;
			kr6->r.if_index = ifindex;
			kr6->r.ticks = smi_getticks();
			kr6->r.priority = prio;

			kroute6_insert(kr6);
		}
		break;
	}

	return (0);
}

struct kroute *
kroute_first(void)
{
	struct kroute_node	*kn;

	kn = RB_MIN(kroute_tree, &krt);
	return (&kn->r);
}

struct kroute *
kroute_getaddr(in_addr_t prefix, u_int8_t prefixlen, u_int8_t prio, int next)
{
	struct kroute_node	*kn;

	kn = kroute_find(prefix, prefixlen, prio);
	if (kn != NULL && next)
		kn = RB_NEXT(kroute_tree, &krt, kn);
	if (kn != NULL)
		return (&kn->r);
	else
		return (NULL);
}