xref: /openbsd/usr.sbin/ripd/kroute.c (revision 891d7ab6)
1 /*	$OpenBSD: kroute.c,v 1.24 2011/07/04 04:34:14 claudio Exp $ */
2 
3 /*
4  * Copyright (c) 2004 Esben Norby <norby@openbsd.org>
5  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/param.h>
21 #include <sys/types.h>
22 #include <sys/socket.h>
23 #include <sys/sysctl.h>
24 #include <sys/tree.h>
25 #include <sys/uio.h>
26 #include <netinet/in.h>
27 #include <arpa/inet.h>
28 #include <net/if.h>
29 #include <net/if_dl.h>
30 #include <net/if_types.h>
31 #include <net/route.h>
32 #include <err.h>
33 #include <errno.h>
34 #include <fcntl.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 
40 #include "rip.h"
41 #include "ripd.h"
42 #include "log.h"
43 
44 struct {
45 	u_int32_t		rtseq;
46 	pid_t			pid;
47 	int			fib_sync;
48 	int			fd;
49 	struct event		ev;
50 	u_int			rdomain;
51 } kr_state;
52 
53 struct kroute_node {
54 	RB_ENTRY(kroute_node)	 entry;
55 	struct kroute		 r;
56 };
57 
58 struct kif_node {
59 	RB_ENTRY(kif_node)	 entry;
60 	struct kif		 k;
61 };
62 
63 void	kr_redistribute(int, struct kroute *);
64 int	kroute_compare(struct kroute_node *, struct kroute_node *);
65 int	kif_compare(struct kif_node *, struct kif_node *);
66 int	kr_change_fib(struct kroute_node *, struct kroute *, int);
67 
68 struct kroute_node	*kroute_find(in_addr_t, in_addr_t, u_int8_t);
69 int			 kroute_insert(struct kroute_node *);
70 int			 kroute_remove(struct kroute_node *);
71 void			 kroute_clear(void);
72 
73 struct kif_node		*kif_find(int);
74 int			 kif_insert(struct kif_node *);
75 int			 kif_remove(struct kif_node *);
76 void			 kif_clear(void);
77 int			 kif_validate(int);
78 
79 struct kroute_node	*kroute_match(in_addr_t);
80 
81 int		protect_lo(void);
82 u_int8_t	prefixlen_classful(in_addr_t);
83 void		get_rtaddrs(int, struct sockaddr *, struct sockaddr **);
84 void		if_change(u_short, int, struct if_data *);
85 void		if_announce(void *);
86 
87 int		send_rtmsg(int, int, struct kroute *);
88 int		dispatch_rtmsg(void);
89 int		fetchtable(void);
90 int		fetchifs(int);
91 
92 RB_HEAD(kroute_tree, kroute_node)	krt;
93 RB_PROTOTYPE(kroute_tree, kroute_node, entry, kroute_compare)
94 RB_GENERATE(kroute_tree, kroute_node, entry, kroute_compare)
95 
96 RB_HEAD(kif_tree, kif_node)		kit;
97 RB_PROTOTYPE(kif_tree, kif_node, entry, kif_compare)
98 RB_GENERATE(kif_tree, kif_node, entry, kif_compare)
99 
100 int
101 kif_init(void)
102 {
103 	RB_INIT(&kit);
104 
105 	if (fetchifs(0) == -1)
106 		return (-1);
107 
108 	return (0);
109 }
110 
111 int
112 kr_init(int fs, u_int rdomain)
113 {
114 	int		opt = 0, rcvbuf, default_rcvbuf;
115 	socklen_t	optlen;
116 
117 	if ((kr_state.fd = socket(AF_ROUTE, SOCK_RAW, 0)) == -1) {
118 		log_warn("kr_init: socket");
119 		return (-1);
120 	}
121 
122 	/* not interested in my own messages */
123 	if (setsockopt(kr_state.fd, SOL_SOCKET, SO_USELOOPBACK,
124 	    &opt, sizeof(opt)) == -1)
125 		log_warn("kr_init: setsockopt");	/* not fatal */
126 
127 	/* grow receive buffer, don't wanna miss messages */
128 	optlen = sizeof(default_rcvbuf);
129 	if (getsockopt(kr_state.fd, SOL_SOCKET, SO_RCVBUF,
130 	    &default_rcvbuf, &optlen) == -1)
131 		log_warn("kr_init getsockopt SOL_SOCKET SO_RCVBUF");
132 	else
133 		for (rcvbuf = MAX_RTSOCK_BUF;
134 		    rcvbuf > default_rcvbuf &&
135 		    setsockopt(kr_state.fd, SOL_SOCKET, SO_RCVBUF,
136 		    &rcvbuf, sizeof(rcvbuf)) == -1 && errno == ENOBUFS;
137 		    rcvbuf /= 2)
138 			;	/* nothing */
139 
140 	kr_state.pid = getpid();
141 	kr_state.rtseq = 1;
142 
143 	RB_INIT(&krt);
144 
145 	if (fetchtable() == -1)
146 		return (-1);
147 
148 	if (protect_lo() == -1)
149 		return (-1);
150 
151 	kr_state.fib_sync = fs; /* now set correct sync mode */
152 	kr_state.rdomain = rdomain;
153 
154 	event_set(&kr_state.ev, kr_state.fd, EV_READ | EV_PERSIST,
155 	    kr_dispatch_msg, NULL);
156 	event_add(&kr_state.ev, NULL);
157 
158 	return (0);
159 }
160 
161 int
162 kr_change_fib(struct kroute_node *kr, struct kroute *kroute, int action)
163 {
164 	/* nexthop within 127/8 -> ignore silently */
165 	if ((kroute->nexthop.s_addr & htonl(IN_CLASSA_NET)) ==
166 	    htonl(INADDR_LOOPBACK & IN_CLASSA_NET))
167 		return (0);
168 
169 	if (send_rtmsg(kr_state.fd, action, kroute) == -1)
170 		return (-1);
171 
172 	if (action == RTM_ADD) {
173 		if ((kr = calloc(1, sizeof(struct kroute_node))) == NULL)
174 			fatal("kr_change_fib");
175 
176 		kr->r.prefix.s_addr = kroute->prefix.s_addr;
177 		kr->r.netmask.s_addr = kroute->netmask.s_addr;
178 		kr->r.nexthop.s_addr = kroute->nexthop.s_addr;
179 		kr->r.flags = kroute->flags |= F_RIPD_INSERTED;
180 		kr->r.priority = RTP_RIP;
181 
182 		if (kroute_insert(kr) == -1) {
183 			log_debug("kr_update_fib: cannot insert %s",
184 			    inet_ntoa(kr->r.nexthop));
185 			free(kr);
186 		}
187 	} else
188 		kr->r.nexthop.s_addr = kroute->nexthop.s_addr;
189 
190 	return (0);
191 }
192 
193 int
194 kr_change(struct kroute *kroute)
195 {
196 	struct kroute_node	*kr;
197 	int			 action = RTM_ADD;
198 
199 	kr = kroute_find(kroute->prefix.s_addr, kroute->netmask.s_addr,
200 	    RTP_RIP);
201 	if (kr != NULL)
202 		action = RTM_CHANGE;
203 
204 	return (kr_change_fib(kr, kroute, action));
205 }
206 
207 int
208 kr_delete(struct kroute *kroute)
209 {
210 	struct kroute_node	*kr;
211 
212 	kr = kroute_find(kroute->prefix.s_addr, kroute->netmask.s_addr,
213 	    RTP_RIP);
214 	if (kr == NULL)
215 		return (0);
216 
217 	if (kr->r.priority != RTP_RIP)
218 		log_warn("kr_delete_fib: %s/%d has wrong priority %d",
219 		    inet_ntoa(kr->r.prefix), mask2prefixlen(kr->r.netmask.s_addr),
220 		    kr->r.priority);
221 
222 	if (send_rtmsg(kr_state.fd, RTM_DELETE, kroute) == -1)
223 		return (-1);
224 
225 	if (kroute_remove(kr) == -1)
226 		return (-1);
227 
228 	return (0);
229 }
230 
231 void
232 kr_shutdown(void)
233 {
234 	kr_fib_decouple();
235 
236 	kroute_clear();
237 	kif_clear();
238 }
239 
240 void
241 kr_fib_couple(void)
242 {
243 	struct kroute_node	*kr;
244 
245 	if (kr_state.fib_sync == 1)	/* already coupled */
246 		return;
247 
248 	kr_state.fib_sync = 1;
249 
250 	RB_FOREACH(kr, kroute_tree, &krt)
251 		if (kr->r.priority == RTP_RIP)
252 			send_rtmsg(kr_state.fd, RTM_ADD, &kr->r);
253 
254 	log_info("kernel routing table coupled");
255 }
256 
257 void
258 kr_fib_decouple(void)
259 {
260 	struct kroute_node	*kr;
261 
262 	if (kr_state.fib_sync == 0)	/* already decoupled */
263 		return;
264 
265 	RB_FOREACH(kr, kroute_tree, &krt)
266 		if (kr->r.priority == RTP_RIP)
267 			send_rtmsg(kr_state.fd, RTM_DELETE, &kr->r);
268 
269 	kr_state.fib_sync = 0;
270 
271 	log_info("kernel routing table decoupled");
272 }
273 
274 /* ARGSUSED */
275 void
276 kr_dispatch_msg(int fd, short event, void *bula)
277 {
278 	dispatch_rtmsg();
279 }
280 
281 void
282 kr_show_route(struct imsg *imsg)
283 {
284 	struct kroute_node	*kr;
285 	int			 flags;
286 	struct in_addr		 addr;
287 
288 	switch (imsg->hdr.type) {
289 	case IMSG_CTL_KROUTE:
290 		if (imsg->hdr.len != IMSG_HEADER_SIZE + sizeof(flags)) {
291 			log_warnx("kr_show_route: wrong imsg len");
292 			return;
293 		}
294 		memcpy(&flags, imsg->data, sizeof(flags));
295 		RB_FOREACH(kr, kroute_tree, &krt)
296 			if (!flags || kr->r.flags & flags) {
297 				main_imsg_compose_ripe(IMSG_CTL_KROUTE,
298 				    imsg->hdr.pid, &kr->r, sizeof(kr->r));
299 			}
300 		break;
301 	case IMSG_CTL_KROUTE_ADDR:
302 		if (imsg->hdr.len != IMSG_HEADER_SIZE +
303 		    sizeof(struct in_addr)) {
304 			log_warnx("kr_show_route: wrong imsg len");
305 			return;
306 		}
307 		memcpy(&addr, imsg->data, sizeof(addr));
308 		kr = NULL;
309 		kr = kroute_match(addr.s_addr);
310 		if (kr != NULL)
311 			main_imsg_compose_ripe(IMSG_CTL_KROUTE, imsg->hdr.pid,
312 			    &kr->r, sizeof(kr->r));
313 		break;
314 	default:
315 		log_debug("kr_show_route: error handling imsg");
316 		break;
317 	}
318 
319 	main_imsg_compose_ripe(IMSG_CTL_END, imsg->hdr.pid, NULL, 0);
320 }
321 
322 void
323 kr_ifinfo(char *ifname, pid_t pid)
324 {
325 	struct kif_node	*kif;
326 
327 	RB_FOREACH(kif, kif_tree, &kit)
328 		if (ifname == NULL || !strcmp(ifname, kif->k.ifname)) {
329 			main_imsg_compose_ripe(IMSG_CTL_IFINFO,
330 			    pid, &kif->k, sizeof(kif->k));
331 		}
332 
333 	main_imsg_compose_ripe(IMSG_CTL_END, pid, NULL, 0);
334 }
335 
336 void
337 kr_redistribute(int type, struct kroute *kr)
338 {
339 	u_int32_t	a;
340 
341 
342 	if (type == IMSG_NETWORK_DEL) {
343 dont_redistribute:
344 		/* was the route redistributed? */
345 		if (kr->flags & F_REDISTRIBUTED) {
346 			/* remove redistributed flag */
347 			kr->flags &= ~F_REDISTRIBUTED;
348 			main_imsg_compose_rde(type, 0, kr,
349 			    sizeof(struct kroute));
350 		}
351 		return;
352 	}
353 
354 	/* interface is not up and running so don't announce */
355 	if (kr->flags & F_DOWN)
356 		return;
357 
358 	/*
359 	 * We consider the loopback net, multicast and experimental addresses
360 	 * as not redistributable.
361 	 */
362 	a = ntohl(kr->prefix.s_addr);
363 	if (IN_MULTICAST(a) || IN_BADCLASS(a) ||
364 	    (a >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
365 		return;
366 	/*
367 	 * Consider networks with nexthop loopback as not redistributable
368 	 * unless it is a reject or blackhole route.
369 	 */
370 	if (kr->nexthop.s_addr == htonl(INADDR_LOOPBACK) &&
371 	    !(kr->flags & (F_BLACKHOLE|F_REJECT)))
372 		return;
373 
374 	/* Should we redistribute this route? */
375 	if (!rip_redistribute(kr))
376 		goto dont_redistribute;
377 
378 	/* Does not matter if we resend the kr, the RDE will cope. */
379 	kr->flags |= F_REDISTRIBUTED;
380 	main_imsg_compose_rde(type, 0, kr, sizeof(struct kroute));
381 }
382 
383 /* rb-tree compare */
384 int
385 kroute_compare(struct kroute_node *a, struct kroute_node *b)
386 {
387 	if (ntohl(a->r.prefix.s_addr) < ntohl(b->r.prefix.s_addr))
388 		return (-1);
389 	if (ntohl(a->r.prefix.s_addr) > ntohl(b->r.prefix.s_addr))
390 		return (1);
391 	if (ntohl(a->r.netmask.s_addr) < ntohl(b->r.netmask.s_addr))
392 		return (-1);
393 	if (ntohl(a->r.netmask.s_addr) > ntohl(b->r.netmask.s_addr))
394 		return (1);
395 
396 	/* if the priority is RTP_ANY finish on the first address hit */
397 	if (a->r.priority == RTP_ANY || b->r.priority == RTP_ANY)
398 		return (0);
399 	if (a->r.priority < b->r.priority)
400 		return (-1);
401 	if (a->r.priority > b->r.priority)
402 		return (1);
403 
404 	return (0);
405 }
406 
407 int
408 kif_compare(struct kif_node *a, struct kif_node *b)
409 {
410 	return (b->k.ifindex - a->k.ifindex);
411 }
412 
413 /* tree management */
414 struct kroute_node *
415 kroute_find(in_addr_t prefix, in_addr_t netmask, u_int8_t prio)
416 {
417 	struct kroute_node	s, *kn, *tmp;
418 
419 	s.r.prefix.s_addr = prefix;
420 	s.r.netmask.s_addr = netmask;
421 	s.r.priority = prio;
422 
423 	kn = RB_FIND(kroute_tree, &krt, &s);
424 	if (kn && prio == RTP_ANY) {
425 		tmp = RB_PREV(kroute_tree, &krt, kn);
426 		while (tmp) {
427 			if (kroute_compare(&s, tmp) == 0)
428 				kn = tmp;
429 			else
430 				break;
431 			tmp = RB_PREV(kroute_tree, &krt, kn);
432 		}
433 	}
434 
435 	return (kn);
436 }
437 
438 int
439 kroute_insert(struct kroute_node *kr)
440 {
441 	if (RB_INSERT(kroute_tree, &krt, kr) != NULL) {
442 		log_warnx("kroute_insert failed for %s/%u",
443 		    inet_ntoa(kr->r.prefix),
444 		    mask2prefixlen(kr->r.netmask.s_addr));
445 		free(kr);
446 		return (-1);
447 	}
448 
449 	if (!(kr->r.flags & F_KERNEL)) {
450 		/* don't validate or redistribute rip route */
451 		kr->r.flags &= ~F_DOWN;
452 		return (0);
453 	}
454 
455 	if (kif_validate(kr->r.ifindex))
456 		kr->r.flags &= ~F_DOWN;
457 	else
458 		kr->r.flags |= F_DOWN;
459 
460 	kr_redistribute(IMSG_NETWORK_ADD, &kr->r);
461 
462 	return (0);
463 }
464 
465 int
466 kroute_remove(struct kroute_node *kr)
467 {
468 	if (RB_REMOVE(kroute_tree, &krt, kr) == NULL) {
469 		log_warnx("kroute_remove failed for %s/%u",
470 		    inet_ntoa(kr->r.prefix),
471 		    mask2prefixlen(kr->r.netmask.s_addr));
472 		return (-1);
473 	}
474 
475 	kr_redistribute(IMSG_NETWORK_DEL, &kr->r);
476 	rtlabel_unref(kr->r.rtlabel);
477 
478 	free(kr);
479 	return (0);
480 }
481 
482 void
483 kroute_clear(void)
484 {
485 	struct kroute_node	*kr;
486 
487 	while ((kr = RB_MIN(kroute_tree, &krt)) != NULL)
488 		kroute_remove(kr);
489 }
490 
491 struct kif_node *
492 kif_find(int ifindex)
493 {
494 	struct kif_node	s;
495 
496 	bzero(&s, sizeof(s));
497 	s.k.ifindex = ifindex;
498 
499 	return (RB_FIND(kif_tree, &kit, &s));
500 }
501 
502 struct kif *
503 kif_findname(char *ifname)
504 {
505 	struct kif_node	*kif;
506 
507 	RB_FOREACH(kif, kif_tree, &kit)
508 		if (!strcmp(ifname, kif->k.ifname))
509 			return (&kif->k);
510 
511 	return (NULL);
512 }
513 
514 int
515 kif_insert(struct kif_node *kif)
516 {
517 	if (RB_INSERT(kif_tree, &kit, kif) != NULL) {
518 		log_warnx("RB_INSERT(kif_tree, &kit, kif)");
519 		free(kif);
520 		return (-1);
521 	}
522 
523 	return (0);
524 }
525 
526 int
527 kif_remove(struct kif_node *kif)
528 {
529 	if (RB_REMOVE(kif_tree, &kit, kif) == NULL) {
530 		log_warnx("RB_REMOVE(kif_tree, &kit, kif)");
531 		return (-1);
532 	}
533 
534 	free(kif);
535 	return (0);
536 }
537 
538 void
539 kif_clear(void)
540 {
541 	struct kif_node	*kif;
542 
543 	while ((kif = RB_MIN(kif_tree, &kit)) != NULL)
544 		kif_remove(kif);
545 }
546 
547 int
548 kif_validate(int ifindex)
549 {
550 	struct kif_node		*kif;
551 
552 	if ((kif = kif_find(ifindex)) == NULL) {
553 		log_warnx("interface with index %u not found", ifindex);
554 		return (1);
555 	}
556 
557 	return (kif->k.nh_reachable);
558 }
559 
560 struct kroute_node *
561 kroute_match(in_addr_t key)
562 {
563 	u_int8_t		 i;
564 	struct kroute_node	*kr;
565 
566 	/* we will never match the default route */
567 	for (i = 32; i > 0; i--)
568 		if ((kr = kroute_find(key & prefixlen2mask(i),
569 		    prefixlen2mask(i), RTP_ANY)) != NULL)
570 			return (kr);
571 
572 	/* if we don't have a match yet, try to find a default route */
573 	if ((kr = kroute_find(0, 0, RTP_ANY)) != NULL)
574 			return (kr);
575 
576 	return (NULL);
577 }
578 
579 /* misc */
580 int
581 protect_lo(void)
582 {
583 	struct kroute_node	*kr;
584 
585 	/* special protection for 127/8 */
586 	if ((kr = calloc(1, sizeof(struct kroute_node))) == NULL) {
587 		log_warn("protect_lo");
588 		return (-1);
589 	}
590 	kr->r.prefix.s_addr = htonl(INADDR_LOOPBACK);
591 	kr->r.netmask.s_addr = htonl(IN_CLASSA_NET);
592 	kr->r.flags = F_KERNEL|F_CONNECTED;
593 
594 	if (RB_INSERT(kroute_tree, &krt, kr) != NULL)
595 		free(kr);	/* kernel route already there, no problem */
596 
597 	return (0);
598 }
599 
600 u_int8_t
601 prefixlen_classful(in_addr_t ina)
602 {
603 	/* it hurt to write this. */
604 
605 	if (ina >= 0xf0000000U)		/* class E */
606 		return (32);
607 	else if (ina >= 0xe0000000U)	/* class D */
608 		return (4);
609 	else if (ina >= 0xc0000000U)	/* class C */
610 		return (24);
611 	else if (ina >= 0x80000000U)	/* class B */
612 		return (16);
613 	else				/* class A */
614 		return (8);
615 }
616 
617 u_int8_t
618 mask2prefixlen(in_addr_t ina)
619 {
620 	if (ina == 0)
621 		return (0);
622 	else
623 		return (33 - ffs(ntohl(ina)));
624 }
625 
626 in_addr_t
627 prefixlen2mask(u_int8_t prefixlen)
628 {
629 	if (prefixlen == 0)
630 		return (0);
631 
632 	return (htonl(0xffffffff << (32 - prefixlen)));
633 }
634 
635 #define	ROUNDUP(a, size)	\
636     (((a) & ((size) - 1)) ? (1 + ((a) | ((size) - 1))) : (a))
637 
638 void
639 get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info)
640 {
641 	int	i;
642 
643 	for (i = 0; i < RTAX_MAX; i++) {
644 		if (addrs & (1 << i)) {
645 			rti_info[i] = sa;
646 			sa = (struct sockaddr *)((char *)(sa) +
647 			    ROUNDUP(sa->sa_len, sizeof(long)));
648 		} else
649 			rti_info[i] = NULL;
650 	}
651 }
652 
653 void
654 if_change(u_short ifindex, int flags, struct if_data *ifd)
655 {
656 	struct kif_node		*kif;
657 	struct kroute_node	*kr;
658 	int			 type;
659 	u_int8_t		 reachable;
660 
661 	if ((kif = kif_find(ifindex)) == NULL) {
662 		log_warnx("interface with index %u not found", ifindex);
663 		return;
664 	}
665 
666 	kif->k.flags = flags;
667 	kif->k.link_state = ifd->ifi_link_state;
668 	kif->k.media_type = ifd->ifi_type;
669 	kif->k.baudrate = ifd->ifi_baudrate;
670 
671 	if ((reachable = (flags & IFF_UP) &&
672 	    LINK_STATE_IS_UP(ifd->ifi_link_state)) == kif->k.nh_reachable)
673 		return;		/* nothing changed wrt nexthop validity */
674 
675 	kif->k.nh_reachable = reachable;
676 	type = reachable ? IMSG_NETWORK_ADD : IMSG_NETWORK_DEL;
677 
678 	/* notify ripe about interface link state */
679 	main_imsg_compose_ripe(IMSG_IFINFO, 0, &kif->k, sizeof(kif->k));
680 
681 	/* update redistribute list */
682 	RB_FOREACH(kr, kroute_tree, &krt)
683 		if (kr->r.ifindex == ifindex) {
684 			if (reachable)
685 				kr->r.flags &= ~F_DOWN;
686 			else
687 				kr->r.flags |= F_DOWN;
688 
689 			kr_redistribute(type, &kr->r);
690 		}
691 }
692 
693 void
694 if_announce(void *msg)
695 {
696 	struct if_announcemsghdr	*ifan;
697 	struct kif_node			*kif;
698 
699 	ifan = msg;
700 
701 	switch (ifan->ifan_what) {
702 	case IFAN_ARRIVAL:
703 		if ((kif = calloc(1, sizeof(struct kif_node))) == NULL) {
704 			log_warn("if_announce");
705 			return;
706 		}
707 
708 		kif->k.ifindex = ifan->ifan_index;
709 		strlcpy(kif->k.ifname, ifan->ifan_name, sizeof(kif->k.ifname));
710 		kif_insert(kif);
711 		break;
712 	case IFAN_DEPARTURE:
713 		kif = kif_find(ifan->ifan_index);
714 		kif_remove(kif);
715 		break;
716 	}
717 }
718 
719 /* rtsock */
720 int
721 send_rtmsg(int fd, int action, struct kroute *kroute)
722 {
723 	struct iovec		iov[4];
724 	struct rt_msghdr	hdr;
725 	struct sockaddr_in	prefix;
726 	struct sockaddr_in	nexthop;
727 	struct sockaddr_in	mask;
728 	int			iovcnt = 0;
729 
730 	if (kr_state.fib_sync == 0)
731 		return (0);
732 
733 	/* initialize header */
734 	bzero(&hdr, sizeof(hdr));
735 	hdr.rtm_version = RTM_VERSION;
736 	hdr.rtm_type = action;
737 	hdr.rtm_priority = RTP_RIP;
738 	hdr.rtm_tableid = kr_state.rdomain;
739 	if (action == RTM_CHANGE)
740 		hdr.rtm_fmask = RTF_REJECT|RTF_BLACKHOLE;
741 	hdr.rtm_seq = kr_state.rtseq++;	/* overflow doesn't matter */
742 	hdr.rtm_msglen = sizeof(hdr);
743 	/* adjust iovec */
744 	iov[iovcnt].iov_base = &hdr;
745 	iov[iovcnt++].iov_len = sizeof(hdr);
746 
747 	bzero(&prefix, sizeof(prefix));
748 	prefix.sin_len = sizeof(prefix);
749 	prefix.sin_family = AF_INET;
750 	prefix.sin_addr.s_addr = kroute->prefix.s_addr;
751 	/* adjust header */
752 	hdr.rtm_addrs |= RTA_DST;
753 	hdr.rtm_msglen += sizeof(prefix);
754 	/* adjust iovec */
755 	iov[iovcnt].iov_base = &prefix;
756 	iov[iovcnt++].iov_len = sizeof(prefix);
757 
758 	if (kroute->nexthop.s_addr != 0) {
759 		bzero(&nexthop, sizeof(nexthop));
760 		nexthop.sin_len = sizeof(nexthop);
761 		nexthop.sin_family = AF_INET;
762 		nexthop.sin_addr.s_addr = kroute->nexthop.s_addr;
763 		/* adjust header */
764 		hdr.rtm_flags |= RTF_GATEWAY;
765 		hdr.rtm_addrs |= RTA_GATEWAY;
766 		hdr.rtm_msglen += sizeof(nexthop);
767 		/* adjust iovec */
768 		iov[iovcnt].iov_base = &nexthop;
769 		iov[iovcnt++].iov_len = sizeof(nexthop);
770 	}
771 
772 	bzero(&mask, sizeof(mask));
773 	mask.sin_len = sizeof(mask);
774 	mask.sin_family = AF_INET;
775 	mask.sin_addr.s_addr = kroute->netmask.s_addr;
776 	/* adjust header */
777 	hdr.rtm_addrs |= RTA_NETMASK;
778 	hdr.rtm_msglen += sizeof(mask);
779 	/* adjust iovec */
780 	iov[iovcnt].iov_base = &mask;
781 	iov[iovcnt++].iov_len = sizeof(mask);
782 
783 
784 retry:
785 	if (writev(fd, iov, iovcnt) == -1) {
786 		if (errno == ESRCH) {
787 			if (hdr.rtm_type == RTM_CHANGE) {
788 				hdr.rtm_type = RTM_ADD;
789 				goto retry;
790 			} else if (hdr.rtm_type == RTM_DELETE) {
791 				log_info("route %s/%u vanished before delete",
792 				    inet_ntoa(kroute->prefix),
793 				    mask2prefixlen(kroute->netmask.s_addr));
794 				return (0);
795 			}
796 		}
797 		log_warn("send_rtmsg: action %u, prefix %s/%u",
798 		    hdr.rtm_type, inet_ntoa(kroute->prefix),
799 		    mask2prefixlen(kroute->netmask.s_addr));
800 		return (0);
801 	}
802 
803 	return (0);
804 }
805 
806 int
807 fetchtable(void)
808 {
809 	size_t			 len;
810 	int			 mib[7];
811 	char			*buf, *next, *lim;
812 	struct rt_msghdr	*rtm;
813 	struct sockaddr		*sa, *rti_info[RTAX_MAX];
814 	struct sockaddr_in	*sa_in;
815 	struct sockaddr_rtlabel	*label;
816 	struct kroute_node	*kr;
817 	struct iface		*iface = NULL;
818 
819 	mib[0] = CTL_NET;
820 	mib[1] = AF_ROUTE;
821 	mib[2] = 0;
822 	mib[3] = AF_INET;
823 	mib[4] = NET_RT_DUMP;
824 	mib[5] = 0;
825 	mib[6] = kr_state.rdomain;	/* rtableid */
826 
827 	if (sysctl(mib, 7, NULL, &len, NULL, 0) == -1) {
828 		log_warn("sysctl");
829 		return (-1);
830 	}
831 	if ((buf = malloc(len)) == NULL) {
832 		log_warn("fetchtable");
833 		return (-1);
834 	}
835 	if (sysctl(mib, 7, buf, &len, NULL, 0) == -1) {
836 		log_warn("sysctl");
837 		free(buf);
838 		return (-1);
839 	}
840 
841 	lim = buf + len;
842 	for (next = buf; next < lim; next += rtm->rtm_msglen) {
843 		rtm = (struct rt_msghdr *)next;
844 		if (rtm->rtm_version != RTM_VERSION)
845 			continue;
846 		sa = (struct sockaddr *)(next + rtm->rtm_hdrlen);
847 		get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
848 
849 		if ((sa = rti_info[RTAX_DST]) == NULL)
850 			continue;
851 
852 		if (rtm->rtm_flags & RTF_LLINFO)	/* arp cache */
853 			continue;
854 
855 #ifdef RTF_MPATH
856 		if (rtm->rtm_flags & RTF_MPATH)		/* multipath */
857 			continue;
858 #endif
859 
860 		if ((kr = calloc(1, sizeof(struct kroute_node))) == NULL) {
861 			log_warn("fetchtable");
862 			free(buf);
863 			return (-1);
864 		}
865 
866 		kr->r.flags = F_KERNEL;
867 		kr->r.priority = rtm->rtm_priority;
868 
869 		switch (sa->sa_family) {
870 		case AF_INET:
871 			kr->r.prefix.s_addr =
872 			    ((struct sockaddr_in *)sa)->sin_addr.s_addr;
873 			sa_in = (struct sockaddr_in *)rti_info[RTAX_NETMASK];
874 			if (rtm->rtm_flags & RTF_STATIC)
875 				kr->r.flags |= F_STATIC;
876 			if (rtm->rtm_flags & RTF_BLACKHOLE)
877 				kr->r.flags |= F_BLACKHOLE;
878 			if (rtm->rtm_flags & RTF_REJECT)
879 				kr->r.flags |= F_REJECT;
880 			if (rtm->rtm_flags & RTF_DYNAMIC)
881 				kr->r.flags |= F_DYNAMIC;
882 			if (sa_in != NULL) {
883 				if (sa_in->sin_len == 0)
884 					break;
885 				kr->r.netmask.s_addr =
886 				    sa_in->sin_addr.s_addr;
887 			} else if (rtm->rtm_flags & RTF_HOST)
888 				kr->r.netmask.s_addr = prefixlen2mask(32);
889 			else
890 				kr->r.netmask.s_addr =
891 				    prefixlen2mask(prefixlen_classful
892 					(kr->r.prefix.s_addr));
893 			break;
894 		default:
895 			free(kr);
896 			continue;
897 		}
898 
899 		kr->r.ifindex = rtm->rtm_index;
900 
901 		iface = if_find_index(rtm->rtm_index);
902 		if (iface != NULL)
903 			kr->r.metric = iface->cost;
904 		else
905 			kr->r.metric = DEFAULT_COST;
906 
907 		if ((sa = rti_info[RTAX_GATEWAY]) != NULL)
908 			switch (sa->sa_family) {
909 			case AF_INET:
910 				kr->r.nexthop.s_addr =
911 				    ((struct sockaddr_in *)sa)->sin_addr.s_addr;
912 				break;
913 			case AF_LINK:
914 				kr->r.flags |= F_CONNECTED;
915 				break;
916 			}
917 
918 		if (rtm->rtm_priority == RTP_RIP) {
919 			send_rtmsg(kr_state.fd, RTM_DELETE, &kr->r);
920 			free(kr);
921 		} else {
922 			if ((label = (struct sockaddr_rtlabel *)
923 			    rti_info[RTAX_LABEL]) != NULL)
924 				kr->r.rtlabel =
925 				    rtlabel_name2id(label->sr_label);
926 			kroute_insert(kr);
927 		}
928 
929 	}
930 	free(buf);
931 	return (0);
932 }
933 
934 int
935 fetchifs(int ifindex)
936 {
937 	size_t			 len;
938 	int			 mib[6];
939 	char			*buf, *next, *lim;
940 	struct if_msghdr	 ifm;
941 	struct kif_node		*kif;
942 	struct sockaddr		*sa, *rti_info[RTAX_MAX];
943 	struct sockaddr_dl	*sdl;
944 
945 	mib[0] = CTL_NET;
946 	mib[1] = AF_ROUTE;
947 	mib[2] = 0;
948 	mib[3] = AF_INET;
949 	mib[4] = NET_RT_IFLIST;
950 	mib[5] = ifindex;
951 
952 	if (sysctl(mib, 6, NULL, &len, NULL, 0) == -1) {
953 		log_warn("sysctl");
954 		return (-1);
955 	}
956 	if ((buf = malloc(len)) == NULL) {
957 		log_warn("fetchif");
958 		return (-1);
959 	}
960 	if (sysctl(mib, 6, buf, &len, NULL, 0) == -1) {
961 		log_warn("sysctl");
962 		free(buf);
963 		return (-1);
964 	}
965 
966 	lim = buf + len;
967 	for (next = buf; next < lim; next += ifm.ifm_msglen) {
968 		memcpy(&ifm, next, sizeof(ifm));
969 		if (ifm.ifm_version != RTM_VERSION)
970 			continue;
971 		if (ifm.ifm_type != RTM_IFINFO)
972 			continue;
973 
974 		sa = (struct sockaddr *)(next + sizeof(ifm));
975 		get_rtaddrs(ifm.ifm_addrs, sa, rti_info);
976 
977 		if ((kif = calloc(1, sizeof(struct kif_node))) == NULL) {
978 			log_warn("fetchifs");
979 			free(buf);
980 			return (-1);
981 		}
982 
983 		kif->k.ifindex = ifm.ifm_index;
984 		kif->k.flags = ifm.ifm_flags;
985 		kif->k.link_state = ifm.ifm_data.ifi_link_state;
986 		kif->k.media_type = ifm.ifm_data.ifi_type;
987 		kif->k.baudrate = ifm.ifm_data.ifi_baudrate;
988 		kif->k.mtu = ifm.ifm_data.ifi_mtu;
989 		kif->k.nh_reachable = (kif->k.flags & IFF_UP) &&
990 		    LINK_STATE_IS_UP(ifm.ifm_data.ifi_link_state);
991 		if ((sa = rti_info[RTAX_IFP]) != NULL)
992 			if (sa->sa_family == AF_LINK) {
993 				sdl = (struct sockaddr_dl *)sa;
994 				if (sdl->sdl_nlen >= sizeof(kif->k.ifname))
995 					memcpy(kif->k.ifname, sdl->sdl_data,
996 					    sizeof(kif->k.ifname) - 1);
997 				else if (sdl->sdl_nlen > 0)
998 					memcpy(kif->k.ifname, sdl->sdl_data,
999 					    sdl->sdl_nlen);
1000 				/* string already terminated via calloc() */
1001 			}
1002 
1003 		kif_insert(kif);
1004 	}
1005 	free(buf);
1006 	return (0);
1007 }
1008 
1009 int
1010 dispatch_rtmsg(void)
1011 {
1012 	char			 buf[RT_BUF_SIZE];
1013 	ssize_t			 n;
1014 	char			*next, *lim;
1015 	struct rt_msghdr	*rtm;
1016 	struct if_msghdr	 ifm;
1017 	struct sockaddr		*sa, *rti_info[RTAX_MAX];
1018 	struct sockaddr_in	*sa_in;
1019 	struct sockaddr_rtlabel	*label;
1020 	struct kroute_node	*kr;
1021 	struct in_addr		 prefix, nexthop, netmask;
1022 	struct iface		*iface = NULL;
1023 	int			 flags;
1024 	u_short			 ifindex = 0;
1025 	u_int8_t		 metric, prio;
1026 
1027 	if ((n = read(kr_state.fd, &buf, sizeof(buf))) == -1) {
1028 		log_warn("dispatch_rtmsg: read error");
1029 		return (-1);
1030 	}
1031 
1032 	if (n == 0) {
1033 		log_warnx("routing socket closed");
1034 		return (-1);
1035 	}
1036 
1037 	lim = buf + n;
1038 	for (next = buf; next < lim; next += rtm->rtm_msglen) {
1039 		rtm = (struct rt_msghdr *)next;
1040 		if (rtm->rtm_version != RTM_VERSION)
1041 			continue;
1042 
1043 		prefix.s_addr = 0;
1044 		netmask.s_addr = 0;
1045 		flags = F_KERNEL;
1046 		nexthop.s_addr = 0;
1047 		prio = 0;
1048 
1049 		if (rtm->rtm_type == RTM_ADD || rtm->rtm_type == RTM_CHANGE ||
1050 		    rtm->rtm_type == RTM_DELETE) {
1051 			sa = (struct sockaddr *)(next + rtm->rtm_hdrlen);
1052 			get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
1053 
1054 			if (rtm->rtm_tableid != kr_state.rdomain)
1055 				continue;
1056 
1057 			if (rtm->rtm_pid == kr_state.pid)	/* cause by us */
1058 				continue;
1059 
1060 			if (rtm->rtm_errno)			/* failed attempts... */
1061 				continue;
1062 
1063 			if (rtm->rtm_flags & RTF_LLINFO)	/* arp cache */
1064 				continue;
1065 
1066 			prio = rtm->rtm_priority;
1067 
1068 			switch (sa->sa_family) {
1069 			case AF_INET:
1070 				prefix.s_addr =
1071 				    ((struct sockaddr_in *)sa)->sin_addr.s_addr;
1072 				sa_in = (struct sockaddr_in *)
1073 				    rti_info[RTAX_NETMASK];
1074 				if (sa_in != NULL) {
1075 					if (sa_in->sin_len != 0)
1076 						netmask.s_addr =
1077 						    sa_in->sin_addr.s_addr;
1078 				} else if (rtm->rtm_flags & RTF_HOST)
1079 					netmask.s_addr = prefixlen2mask(32);
1080 				else
1081 					netmask.s_addr =
1082 					    prefixlen2mask(prefixlen_classful(
1083 						prefix.s_addr));
1084 				if (rtm->rtm_flags & RTF_STATIC)
1085 					flags |= F_STATIC;
1086 				if (rtm->rtm_flags & RTF_BLACKHOLE)
1087 					flags |= F_BLACKHOLE;
1088 				if (rtm->rtm_flags & RTF_REJECT)
1089 					flags |= F_REJECT;
1090 				if (rtm->rtm_flags & RTF_DYNAMIC)
1091 					flags |= F_DYNAMIC;
1092 				break;
1093 			default:
1094 				continue;
1095 			}
1096 
1097 			ifindex = rtm->rtm_index;
1098 			if ((sa = rti_info[RTAX_GATEWAY]) != NULL) {
1099 				switch (sa->sa_family) {
1100 				case AF_INET:
1101 					nexthop.s_addr = ((struct
1102 					    sockaddr_in *)sa)->sin_addr.s_addr;
1103 					break;
1104 				case AF_LINK:
1105 					flags |= F_CONNECTED;
1106 					break;
1107 				}
1108 			}
1109 		}
1110 
1111 		switch (rtm->rtm_type) {
1112 		case RTM_ADD:
1113 		case RTM_CHANGE:
1114 			if (nexthop.s_addr == 0 && !(flags & F_CONNECTED)) {
1115 				log_warnx("dispatch_rtmsg no nexthop for %s/%u",
1116 				    inet_ntoa(prefix),
1117 				    mask2prefixlen(netmask.s_addr));
1118 				continue;
1119 			}
1120 
1121 			if ((kr = kroute_find(prefix.s_addr, netmask.s_addr,
1122 			    prio)) != NULL) {
1123 				if (kr->r.flags & F_REDISTRIBUTED)
1124 					flags |= F_REDISTRIBUTED;
1125 				kr->r.nexthop.s_addr = nexthop.s_addr;
1126 				kr->r.flags = flags;
1127 				kr->r.ifindex = ifindex;
1128 				kr->r.priority = prio;
1129 
1130 				rtlabel_unref(kr->r.rtlabel);
1131 				kr->r.rtlabel = 0;
1132 				if ((label = (struct sockaddr_rtlabel *)
1133 				    rti_info[RTAX_LABEL]) != NULL)
1134 					kr->r.rtlabel =
1135 					    rtlabel_name2id(label->sr_label);
1136 
1137 				if (kif_validate(kr->r.ifindex))
1138 					kr->r.flags &= ~F_DOWN;
1139 				else
1140 					kr->r.flags |= F_DOWN;
1141 
1142 				/* just readd, the RDE will care */
1143 				kr_redistribute(IMSG_NETWORK_ADD, &kr->r);
1144 			} else {
1145 				if ((kr = calloc(1,
1146 				    sizeof(struct kroute_node))) == NULL) {
1147 					log_warn("dispatch_rtmsg");
1148 					return (-1);
1149 				}
1150 
1151 				iface = if_find_index(rtm->rtm_index);
1152 				if (iface != NULL)
1153 					metric = iface->cost;
1154 				else
1155 					metric = DEFAULT_COST;
1156 
1157 				kr->r.prefix.s_addr = prefix.s_addr;
1158 				kr->r.netmask.s_addr = netmask.s_addr;
1159 				kr->r.nexthop.s_addr = nexthop.s_addr;
1160 				kr->r.metric = metric;
1161 				kr->r.flags = flags;
1162 				kr->r.ifindex = ifindex;
1163 
1164 				if ((label = (struct sockaddr_rtlabel *)
1165 				    rti_info[RTAX_LABEL]) != NULL)
1166 					kr->r.rtlabel =
1167 					    rtlabel_name2id(label->sr_label);
1168 
1169 				kroute_insert(kr);
1170 			}
1171 			break;
1172 		case RTM_DELETE:
1173 			if ((kr = kroute_find(prefix.s_addr, netmask.s_addr,
1174 			    prio)) == NULL)
1175 				continue;
1176 			if (!(kr->r.flags & F_KERNEL))
1177 				continue;
1178 			if (kroute_remove(kr) == -1)
1179 				return (-1);
1180 			break;
1181 		case RTM_IFINFO:
1182 			memcpy(&ifm, next, sizeof(ifm));
1183 			if_change(ifm.ifm_index, ifm.ifm_flags,
1184 			    &ifm.ifm_data);
1185 			break;
1186 		case RTM_IFANNOUNCE:
1187 			if_announce(next);
1188 			break;
1189 		default:
1190 			/* ignore for now */
1191 			break;
1192 		}
1193 	}
1194 	return (0);
1195 }
1196