xref: /freebsd/sys/net/route.c (revision 732a02b4e77866604a120a275c082bb6221bd2ff)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1986, 1991, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)route.c	8.3.1.1 (Berkeley) 2/23/95
32  * $FreeBSD$
33  */
34 /************************************************************************
35  * Note: In this file a 'fib' is a "forwarding information base"	*
36  * Which is the new name for an in kernel routing (next hop) table.	*
37  ***********************************************************************/
38 
39 #include "opt_inet.h"
40 #include "opt_inet6.h"
41 #include "opt_mrouting.h"
42 #include "opt_mpath.h"
43 #include "opt_route.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/malloc.h>
48 #include <sys/mbuf.h>
49 #include <sys/socket.h>
50 #include <sys/sysctl.h>
51 #include <sys/syslog.h>
52 #include <sys/sysproto.h>
53 #include <sys/proc.h>
54 #include <sys/domain.h>
55 #include <sys/eventhandler.h>
56 #include <sys/kernel.h>
57 #include <sys/lock.h>
58 #include <sys/rmlock.h>
59 
60 #include <net/if.h>
61 #include <net/if_var.h>
62 #include <net/if_dl.h>
63 #include <net/route.h>
64 #include <net/route_var.h>
65 #include <net/route/nhop.h>
66 #include <net/route/shared.h>
67 #include <net/vnet.h>
68 
69 #ifdef RADIX_MPATH
70 #include <net/radix_mpath.h>
71 #endif
72 
73 #include <netinet/in.h>
74 #include <netinet/ip_mroute.h>
75 
76 #include <vm/uma.h>
77 
78 #define	RT_MAXFIBS	UINT16_MAX
79 
80 /* Kernel config default option. */
81 #ifdef ROUTETABLES
82 #if ROUTETABLES <= 0
83 #error "ROUTETABLES defined too low"
84 #endif
85 #if ROUTETABLES > RT_MAXFIBS
86 #error "ROUTETABLES defined too big"
87 #endif
88 #define	RT_NUMFIBS	ROUTETABLES
89 #endif /* ROUTETABLES */
90 /* Initialize to default if not otherwise set. */
91 #ifndef	RT_NUMFIBS
92 #define	RT_NUMFIBS	1
93 #endif
94 
95 /* This is read-only.. */
96 u_int rt_numfibs = RT_NUMFIBS;
97 SYSCTL_UINT(_net, OID_AUTO, fibs, CTLFLAG_RDTUN, &rt_numfibs, 0, "");
98 
99 /*
100  * By default add routes to all fibs for new interfaces.
101  * Once this is set to 0 then only allocate routes on interface
102  * changes for the FIB of the caller when adding a new set of addresses
103  * to an interface.  XXX this is a shotgun aproach to a problem that needs
104  * a more fine grained solution.. that will come.
105  * XXX also has the problems getting the FIB from curthread which will not
106  * always work given the fib can be overridden and prefixes can be added
107  * from the network stack context.
108  */
109 VNET_DEFINE(u_int, rt_add_addr_allfibs) = 1;
110 SYSCTL_UINT(_net, OID_AUTO, add_addr_allfibs, CTLFLAG_RWTUN | CTLFLAG_VNET,
111     &VNET_NAME(rt_add_addr_allfibs), 0, "");
112 
113 VNET_PCPUSTAT_DEFINE(struct rtstat, rtstat);
114 
115 VNET_PCPUSTAT_SYSINIT(rtstat);
116 #ifdef VIMAGE
117 VNET_PCPUSTAT_SYSUNINIT(rtstat);
118 #endif
119 
120 VNET_DEFINE(struct rib_head *, rt_tables);
121 #define	V_rt_tables	VNET(rt_tables)
122 
123 VNET_DEFINE(int, rttrash);		/* routes not in table but not freed */
124 #define	V_rttrash	VNET(rttrash)
125 
126 
127 /*
128  * Convert a 'struct radix_node *' to a 'struct rtentry *'.
129  * The operation can be done safely (in this code) because a
130  * 'struct rtentry' starts with two 'struct radix_node''s, the first
131  * one representing leaf nodes in the routing tree, which is
132  * what the code in radix.c passes us as a 'struct radix_node'.
133  *
134  * But because there are a lot of assumptions in this conversion,
135  * do not cast explicitly, but always use the macro below.
136  */
137 #define RNTORT(p)	((struct rtentry *)(p))
138 
139 VNET_DEFINE_STATIC(uma_zone_t, rtzone);		/* Routing table UMA zone. */
140 #define	V_rtzone	VNET(rtzone)
141 
142 EVENTHANDLER_LIST_DEFINE(rt_addrmsg);
143 
144 static int rt_getifa_fib(struct rt_addrinfo *, u_int);
145 static void rt_setmetrics(const struct rt_addrinfo *, struct rtentry *);
146 static int rt_ifdelroute(const struct rtentry *rt, const struct nhop_object *,
147     void *arg);
148 static struct rtentry *rt_unlinkrte(struct rib_head *rnh,
149     struct rt_addrinfo *info, int *perror);
150 static void rt_notifydelete(struct rtentry *rt, struct rt_addrinfo *info);
151 #ifdef RADIX_MPATH
152 static struct radix_node *rt_mpath_unlink(struct rib_head *rnh,
153     struct rt_addrinfo *info, struct rtentry *rto, int *perror);
154 #endif
155 static int rt_exportinfo(struct rtentry *rt, struct rt_addrinfo *info,
156     int flags);
157 
158 static int add_route(struct rib_head *rnh, struct rt_addrinfo *info,
159     struct rtentry **ret_nrt);
160 static int del_route(struct rib_head *rnh, struct rt_addrinfo *info,
161     struct rtentry **ret_nrt);
162 static int change_route(struct rib_head *, struct rt_addrinfo *,
163     struct rtentry **);
164 
165 struct if_mtuinfo
166 {
167 	struct ifnet	*ifp;
168 	int		mtu;
169 };
170 
171 static int	if_updatemtu_cb(struct radix_node *, void *);
172 
173 /*
174  * handler for net.my_fibnum
175  */
176 static int
177 sysctl_my_fibnum(SYSCTL_HANDLER_ARGS)
178 {
179         int fibnum;
180         int error;
181 
182         fibnum = curthread->td_proc->p_fibnum;
183         error = sysctl_handle_int(oidp, &fibnum, 0, req);
184         return (error);
185 }
186 
187 SYSCTL_PROC(_net, OID_AUTO, my_fibnum,
188     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
189     &sysctl_my_fibnum, "I",
190     "default FIB of caller");
191 
192 static __inline struct rib_head **
193 rt_tables_get_rnh_ptr(int table, int fam)
194 {
195 	struct rib_head **rnh;
196 
197 	KASSERT(table >= 0 && table < rt_numfibs,
198 	    ("%s: table out of bounds (0 <= %d < %d)", __func__, table,
199 	     rt_numfibs));
200 	KASSERT(fam >= 0 && fam < (AF_MAX + 1),
201 	    ("%s: fam out of bounds (0 <= %d < %d)", __func__, fam, AF_MAX+1));
202 
203 	/* rnh is [fib=0][af=0]. */
204 	rnh = (struct rib_head **)V_rt_tables;
205 	/* Get the offset to the requested table and fam. */
206 	rnh += table * (AF_MAX+1) + fam;
207 
208 	return (rnh);
209 }
210 
211 struct rib_head *
212 rt_tables_get_rnh(int table, int fam)
213 {
214 
215 	return (*rt_tables_get_rnh_ptr(table, fam));
216 }
217 
218 u_int
219 rt_tables_get_gen(int table, int fam)
220 {
221 	struct rib_head *rnh;
222 
223 	rnh = *rt_tables_get_rnh_ptr(table, fam);
224 	KASSERT(rnh != NULL, ("%s: NULL rib_head pointer table %d fam %d",
225 	    __func__, table, fam));
226 	return (rnh->rnh_gen);
227 }
228 
229 
230 /*
231  * route initialization must occur before ip6_init2(), which happenas at
232  * SI_ORDER_MIDDLE.
233  */
234 static void
235 route_init(void)
236 {
237 
238 	/* whack the tunable ints into  line. */
239 	if (rt_numfibs > RT_MAXFIBS)
240 		rt_numfibs = RT_MAXFIBS;
241 	if (rt_numfibs == 0)
242 		rt_numfibs = 1;
243 	nhops_init();
244 }
245 SYSINIT(route_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, NULL);
246 
247 static int
248 rtentry_zinit(void *mem, int size, int how)
249 {
250 	struct rtentry *rt = mem;
251 
252 	rt->rt_pksent = counter_u64_alloc(how);
253 	if (rt->rt_pksent == NULL)
254 		return (ENOMEM);
255 
256 	RT_LOCK_INIT(rt);
257 
258 	return (0);
259 }
260 
261 static void
262 rtentry_zfini(void *mem, int size)
263 {
264 	struct rtentry *rt = mem;
265 
266 	RT_LOCK_DESTROY(rt);
267 	counter_u64_free(rt->rt_pksent);
268 }
269 
270 static int
271 rtentry_ctor(void *mem, int size, void *arg, int how)
272 {
273 	struct rtentry *rt = mem;
274 
275 	bzero(rt, offsetof(struct rtentry, rt_endzero));
276 	counter_u64_zero(rt->rt_pksent);
277 	rt->rt_chain = NULL;
278 
279 	return (0);
280 }
281 
282 static void
283 rtentry_dtor(void *mem, int size, void *arg)
284 {
285 	struct rtentry *rt = mem;
286 
287 	RT_UNLOCK_COND(rt);
288 }
289 
290 static void
291 vnet_route_init(const void *unused __unused)
292 {
293 	struct domain *dom;
294 	struct rib_head **rnh;
295 	int table;
296 	int fam;
297 
298 	V_rt_tables = malloc(rt_numfibs * (AF_MAX+1) *
299 	    sizeof(struct rib_head *), M_RTABLE, M_WAITOK|M_ZERO);
300 
301 	V_rtzone = uma_zcreate("rtentry", sizeof(struct rtentry),
302 	    rtentry_ctor, rtentry_dtor,
303 	    rtentry_zinit, rtentry_zfini, UMA_ALIGN_PTR, 0);
304 	for (dom = domains; dom; dom = dom->dom_next) {
305 		if (dom->dom_rtattach == NULL)
306 			continue;
307 
308 		for  (table = 0; table < rt_numfibs; table++) {
309 			fam = dom->dom_family;
310 			if (table != 0 && fam != AF_INET6 && fam != AF_INET)
311 				break;
312 
313 			rnh = rt_tables_get_rnh_ptr(table, fam);
314 			if (rnh == NULL)
315 				panic("%s: rnh NULL", __func__);
316 			dom->dom_rtattach((void **)rnh, 0, table);
317 		}
318 	}
319 }
320 VNET_SYSINIT(vnet_route_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
321     vnet_route_init, 0);
322 
323 #ifdef VIMAGE
324 static void
325 vnet_route_uninit(const void *unused __unused)
326 {
327 	int table;
328 	int fam;
329 	struct domain *dom;
330 	struct rib_head **rnh;
331 
332 	for (dom = domains; dom; dom = dom->dom_next) {
333 		if (dom->dom_rtdetach == NULL)
334 			continue;
335 
336 		for (table = 0; table < rt_numfibs; table++) {
337 			fam = dom->dom_family;
338 
339 			if (table != 0 && fam != AF_INET6 && fam != AF_INET)
340 				break;
341 
342 			rnh = rt_tables_get_rnh_ptr(table, fam);
343 			if (rnh == NULL)
344 				panic("%s: rnh NULL", __func__);
345 			dom->dom_rtdetach((void **)rnh, 0);
346 		}
347 	}
348 
349 	free(V_rt_tables, M_RTABLE);
350 	uma_zdestroy(V_rtzone);
351 }
352 VNET_SYSUNINIT(vnet_route_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST,
353     vnet_route_uninit, 0);
354 #endif
355 
356 struct rib_head *
357 rt_table_init(int offset, int family, u_int fibnum)
358 {
359 	struct rib_head *rh;
360 
361 	rh = malloc(sizeof(struct rib_head), M_RTABLE, M_WAITOK | M_ZERO);
362 
363 	/* TODO: These details should be hidded inside radix.c */
364 	/* Init masks tree */
365 	rn_inithead_internal(&rh->head, rh->rnh_nodes, offset);
366 	rn_inithead_internal(&rh->rmhead.head, rh->rmhead.mask_nodes, 0);
367 	rh->head.rnh_masks = &rh->rmhead;
368 
369 	/* Save metadata associated with this routing table. */
370 	rh->rib_family = family;
371 	rh->rib_fibnum = fibnum;
372 #ifdef VIMAGE
373 	rh->rib_vnet = curvnet;
374 #endif
375 
376 	tmproutes_init(rh);
377 
378 	/* Init locks */
379 	RIB_LOCK_INIT(rh);
380 
381 	nhops_init_rib(rh);
382 
383 	/* Finally, set base callbacks */
384 	rh->rnh_addaddr = rn_addroute;
385 	rh->rnh_deladdr = rn_delete;
386 	rh->rnh_matchaddr = rn_match;
387 	rh->rnh_lookup = rn_lookup;
388 	rh->rnh_walktree = rn_walktree;
389 	rh->rnh_walktree_from = rn_walktree_from;
390 
391 	return (rh);
392 }
393 
394 static int
395 rt_freeentry(struct radix_node *rn, void *arg)
396 {
397 	struct radix_head * const rnh = arg;
398 	struct radix_node *x;
399 
400 	x = (struct radix_node *)rn_delete(rn + 2, NULL, rnh);
401 	if (x != NULL)
402 		R_Free(x);
403 	return (0);
404 }
405 
406 void
407 rt_table_destroy(struct rib_head *rh)
408 {
409 
410 	tmproutes_destroy(rh);
411 
412 	rn_walktree(&rh->rmhead.head, rt_freeentry, &rh->rmhead.head);
413 
414 	nhops_destroy_rib(rh);
415 
416 	/* Assume table is already empty */
417 	RIB_LOCK_DESTROY(rh);
418 	free(rh, M_RTABLE);
419 }
420 
421 
422 #ifndef _SYS_SYSPROTO_H_
423 struct setfib_args {
424 	int     fibnum;
425 };
426 #endif
427 int
428 sys_setfib(struct thread *td, struct setfib_args *uap)
429 {
430 	if (uap->fibnum < 0 || uap->fibnum >= rt_numfibs)
431 		return EINVAL;
432 	td->td_proc->p_fibnum = uap->fibnum;
433 	return (0);
434 }
435 
436 /*
437  * Packet routing routines.
438  */
439 void
440 rtalloc_ign_fib(struct route *ro, u_long ignore, u_int fibnum)
441 {
442 	struct rtentry *rt;
443 
444 	if ((rt = ro->ro_rt) != NULL) {
445 		if (rt->rt_ifp != NULL && rt->rt_flags & RTF_UP)
446 			return;
447 		RTFREE(rt);
448 		ro->ro_rt = NULL;
449 	}
450 	ro->ro_rt = rtalloc1_fib(&ro->ro_dst, 1, ignore, fibnum);
451 	if (ro->ro_rt)
452 		RT_UNLOCK(ro->ro_rt);
453 }
454 
455 /*
456  * Look up the route that matches the address given
457  * Or, at least try.. Create a cloned route if needed.
458  *
459  * The returned route, if any, is locked.
460  */
461 struct rtentry *
462 rtalloc1(struct sockaddr *dst, int report, u_long ignflags)
463 {
464 
465 	return (rtalloc1_fib(dst, report, ignflags, RT_DEFAULT_FIB));
466 }
467 
468 struct rtentry *
469 rtalloc1_fib(struct sockaddr *dst, int report, u_long ignflags,
470 		    u_int fibnum)
471 {
472 	RIB_RLOCK_TRACKER;
473 	struct rib_head *rh;
474 	struct radix_node *rn;
475 	struct rtentry *newrt;
476 	struct rt_addrinfo info;
477 	int err = 0, msgtype = RTM_MISS;
478 
479 	KASSERT((fibnum < rt_numfibs), ("rtalloc1_fib: bad fibnum"));
480 	rh = rt_tables_get_rnh(fibnum, dst->sa_family);
481 	newrt = NULL;
482 	if (rh == NULL)
483 		goto miss;
484 
485 	/*
486 	 * Look up the address in the table for that Address Family
487 	 */
488 	if ((ignflags & RTF_RNH_LOCKED) == 0)
489 		RIB_RLOCK(rh);
490 #ifdef INVARIANTS
491 	else
492 		RIB_LOCK_ASSERT(rh);
493 #endif
494 	rn = rh->rnh_matchaddr(dst, &rh->head);
495 	if (rn && ((rn->rn_flags & RNF_ROOT) == 0)) {
496 		newrt = RNTORT(rn);
497 		RT_LOCK(newrt);
498 		RT_ADDREF(newrt);
499 		if ((ignflags & RTF_RNH_LOCKED) == 0)
500 			RIB_RUNLOCK(rh);
501 		return (newrt);
502 
503 	} else if ((ignflags & RTF_RNH_LOCKED) == 0)
504 		RIB_RUNLOCK(rh);
505 	/*
506 	 * Either we hit the root or could not find any match,
507 	 * which basically means: "cannot get there from here".
508 	 */
509 miss:
510 	RTSTAT_INC(rts_unreach);
511 
512 	if (report) {
513 		/*
514 		 * If required, report the failure to the supervising
515 		 * Authorities.
516 		 * For a delete, this is not an error. (report == 0)
517 		 */
518 		bzero(&info, sizeof(info));
519 		info.rti_info[RTAX_DST] = dst;
520 		rt_missmsg_fib(msgtype, &info, 0, err, fibnum);
521 	}
522 	return (newrt);
523 }
524 
525 /*
526  * Remove a reference count from an rtentry.
527  * If the count gets low enough, take it out of the routing table
528  */
529 void
530 rtfree(struct rtentry *rt)
531 {
532 	struct rib_head *rnh;
533 
534 	KASSERT(rt != NULL,("%s: NULL rt", __func__));
535 	rnh = rt_tables_get_rnh(rt->rt_fibnum, rt_key(rt)->sa_family);
536 	KASSERT(rnh != NULL,("%s: NULL rnh", __func__));
537 
538 	RT_LOCK_ASSERT(rt);
539 
540 	/*
541 	 * The callers should use RTFREE_LOCKED() or RTFREE(), so
542 	 * we should come here exactly with the last reference.
543 	 */
544 	RT_REMREF(rt);
545 	if (rt->rt_refcnt > 0) {
546 		log(LOG_DEBUG, "%s: %p has %d refs\n", __func__, rt, rt->rt_refcnt);
547 		goto done;
548 	}
549 
550 	/*
551 	 * On last reference give the "close method" a chance
552 	 * to cleanup private state.  This also permits (for
553 	 * IPv4 and IPv6) a chance to decide if the routing table
554 	 * entry should be purged immediately or at a later time.
555 	 * When an immediate purge is to happen the close routine
556 	 * typically calls rtexpunge which clears the RTF_UP flag
557 	 * on the entry so that the code below reclaims the storage.
558 	 */
559 	if (rt->rt_refcnt == 0 && rnh->rnh_close)
560 		rnh->rnh_close((struct radix_node *)rt, &rnh->head);
561 
562 	/*
563 	 * If we are no longer "up" (and ref == 0)
564 	 * then we can free the resources associated
565 	 * with the route.
566 	 */
567 	if ((rt->rt_flags & RTF_UP) == 0) {
568 		if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT))
569 			panic("rtfree 2");
570 		/*
571 		 * the rtentry must have been removed from the routing table
572 		 * so it is represented in rttrash.. remove that now.
573 		 */
574 		V_rttrash--;
575 #ifdef	DIAGNOSTIC
576 		if (rt->rt_refcnt < 0) {
577 			printf("rtfree: %p not freed (neg refs)\n", rt);
578 			goto done;
579 		}
580 #endif
581 		/*
582 		 * release references on items we hold them on..
583 		 * e.g other routes and ifaddrs.
584 		 */
585 		if (rt->rt_ifa)
586 			ifa_free(rt->rt_ifa);
587 		/*
588 		 * The key is separatly alloc'd so free it (see rt_setgate()).
589 		 * This also frees the gateway, as they are always malloc'd
590 		 * together.
591 		 */
592 		R_Free(rt_key(rt));
593 
594 		/* Unreference nexthop */
595 		nhop_free(rt->rt_nhop);
596 
597 		/*
598 		 * and the rtentry itself of course
599 		 */
600 		uma_zfree(V_rtzone, rt);
601 		return;
602 	}
603 done:
604 	RT_UNLOCK(rt);
605 }
606 
607 /*
608  * Temporary RTFREE() function wrapper.
609  *  Intended to use in control plane code to
610  *  avoid exposing internal layout of 'struct rtentry'.
611  */
612 void
613 rtfree_func(struct rtentry *rt)
614 {
615 
616 	RTFREE(rt);
617 }
618 
619 /*
620  * Adds a temporal redirect entry to the routing table.
621  * @fibnum: fib number
622  * @dst: destination to install redirect to
623  * @gateway: gateway to go via
624  * @author: sockaddr of originating router, can be NULL
625  * @ifp: interface to use for the redirected route
626  * @flags: set of flags to add. Allowed: RTF_GATEWAY
627  * @lifetime_sec: time in seconds to expire this redirect.
628  *
629  * Retuns 0 on success, errno otherwise.
630  */
631 int
632 rib_add_redirect(u_int fibnum, struct sockaddr *dst, struct sockaddr *gateway,
633     struct sockaddr *author, struct ifnet *ifp, int flags, int lifetime_sec)
634 {
635 	struct rtentry *rt;
636 	int error;
637 	struct rt_addrinfo info;
638 	struct rt_metrics rti_rmx;
639 	struct ifaddr *ifa;
640 
641 	NET_EPOCH_ASSERT();
642 
643 	if (rt_tables_get_rnh(fibnum, dst->sa_family) == NULL)
644 		return (EAFNOSUPPORT);
645 
646 	/* Verify the allowed flag mask. */
647 	KASSERT(((flags & ~(RTF_GATEWAY)) == 0),
648 	    ("invalid redirect flags: %x", flags));
649 
650 	/* Get the best ifa for the given interface and gateway. */
651 	if ((ifa = ifaof_ifpforaddr(gateway, ifp)) == NULL)
652 		return (ENETUNREACH);
653 	ifa_ref(ifa);
654 
655 	bzero(&info, sizeof(info));
656 	info.rti_info[RTAX_DST] = dst;
657 	info.rti_info[RTAX_GATEWAY] = gateway;
658 	info.rti_ifa = ifa;
659 	info.rti_ifp = ifp;
660 	info.rti_flags = flags | RTF_HOST | RTF_DYNAMIC;
661 
662 	/* Setup route metrics to define expire time. */
663 	bzero(&rti_rmx, sizeof(rti_rmx));
664 	/* Set expire time as absolute. */
665 	rti_rmx.rmx_expire = lifetime_sec + time_second;
666 	info.rti_mflags |= RTV_EXPIRE;
667 	info.rti_rmx = &rti_rmx;
668 
669 	error = rtrequest1_fib(RTM_ADD, &info, &rt, fibnum);
670 	ifa_free(ifa);
671 
672 	if (error != 0) {
673 		/* TODO: add per-fib redirect stats. */
674 		return (error);
675 	}
676 
677 	RT_LOCK(rt);
678 	flags = rt->rt_flags;
679 	RTFREE_LOCKED(rt);
680 
681 	RTSTAT_INC(rts_dynamic);
682 
683 	/* Send notification of a route addition to userland. */
684 	bzero(&info, sizeof(info));
685 	info.rti_info[RTAX_DST] = dst;
686 	info.rti_info[RTAX_GATEWAY] = gateway;
687 	info.rti_info[RTAX_AUTHOR] = author;
688 	rt_missmsg_fib(RTM_REDIRECT, &info, flags, error, fibnum);
689 
690 	return (0);
691 }
692 
693 /*
694  * Routing table ioctl interface.
695  */
696 int
697 rtioctl_fib(u_long req, caddr_t data, u_int fibnum)
698 {
699 
700 	/*
701 	 * If more ioctl commands are added here, make sure the proper
702 	 * super-user checks are being performed because it is possible for
703 	 * prison-root to make it this far if raw sockets have been enabled
704 	 * in jails.
705 	 */
706 #ifdef INET
707 	/* Multicast goop, grrr... */
708 	return mrt_ioctl ? mrt_ioctl(req, data, fibnum) : EOPNOTSUPP;
709 #else /* INET */
710 	return ENXIO;
711 #endif /* INET */
712 }
713 
714 struct ifaddr *
715 ifa_ifwithroute(int flags, const struct sockaddr *dst, struct sockaddr *gateway,
716 				u_int fibnum)
717 {
718 	struct ifaddr *ifa;
719 	int not_found = 0;
720 
721 	NET_EPOCH_ASSERT();
722 	if ((flags & RTF_GATEWAY) == 0) {
723 		/*
724 		 * If we are adding a route to an interface,
725 		 * and the interface is a pt to pt link
726 		 * we should search for the destination
727 		 * as our clue to the interface.  Otherwise
728 		 * we can use the local address.
729 		 */
730 		ifa = NULL;
731 		if (flags & RTF_HOST)
732 			ifa = ifa_ifwithdstaddr(dst, fibnum);
733 		if (ifa == NULL)
734 			ifa = ifa_ifwithaddr(gateway);
735 	} else {
736 		/*
737 		 * If we are adding a route to a remote net
738 		 * or host, the gateway may still be on the
739 		 * other end of a pt to pt link.
740 		 */
741 		ifa = ifa_ifwithdstaddr(gateway, fibnum);
742 	}
743 	if (ifa == NULL)
744 		ifa = ifa_ifwithnet(gateway, 0, fibnum);
745 	if (ifa == NULL) {
746 		struct rtentry *rt;
747 
748 		rt = rtalloc1_fib(gateway, 0, flags, fibnum);
749 		if (rt == NULL)
750 			goto out;
751 		/*
752 		 * dismiss a gateway that is reachable only
753 		 * through the default router
754 		 */
755 		switch (gateway->sa_family) {
756 		case AF_INET:
757 			if (satosin(rt_key(rt))->sin_addr.s_addr == INADDR_ANY)
758 				not_found = 1;
759 			break;
760 		case AF_INET6:
761 			if (IN6_IS_ADDR_UNSPECIFIED(&satosin6(rt_key(rt))->sin6_addr))
762 				not_found = 1;
763 			break;
764 		default:
765 			break;
766 		}
767 		if (!not_found && rt->rt_ifa != NULL) {
768 			ifa = rt->rt_ifa;
769 		}
770 		RT_REMREF(rt);
771 		RT_UNLOCK(rt);
772 		if (not_found || ifa == NULL)
773 			goto out;
774 	}
775 	if (ifa->ifa_addr->sa_family != dst->sa_family) {
776 		struct ifaddr *oifa = ifa;
777 		ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
778 		if (ifa == NULL)
779 			ifa = oifa;
780 	}
781  out:
782 	return (ifa);
783 }
784 
785 /*
786  * Do appropriate manipulations of a routing tree given
787  * all the bits of info needed
788  */
789 int
790 rtrequest_fib(int req,
791 	struct sockaddr *dst,
792 	struct sockaddr *gateway,
793 	struct sockaddr *netmask,
794 	int flags,
795 	struct rtentry **ret_nrt,
796 	u_int fibnum)
797 {
798 	struct rt_addrinfo info;
799 
800 	if (dst->sa_len == 0)
801 		return(EINVAL);
802 
803 	bzero((caddr_t)&info, sizeof(info));
804 	info.rti_flags = flags;
805 	info.rti_info[RTAX_DST] = dst;
806 	info.rti_info[RTAX_GATEWAY] = gateway;
807 	info.rti_info[RTAX_NETMASK] = netmask;
808 	return rtrequest1_fib(req, &info, ret_nrt, fibnum);
809 }
810 
811 
812 /*
813  * Copy most of @rt data into @info.
814  *
815  * If @flags contains NHR_COPY, copies dst,netmask and gw to the
816  * pointers specified by @info structure. Assume such pointers
817  * are zeroed sockaddr-like structures with sa_len field initialized
818  * to reflect size of the provided buffer. if no NHR_COPY is specified,
819  * point dst,netmask and gw @info fields to appropriate @rt values.
820  *
821  * if @flags contains NHR_REF, do refcouting on rt_ifp and rt_ifa.
822  *
823  * Returns 0 on success.
824  */
825 int
826 rt_exportinfo(struct rtentry *rt, struct rt_addrinfo *info, int flags)
827 {
828 	struct rt_metrics *rmx;
829 	struct sockaddr *src, *dst;
830 	int sa_len;
831 
832 	if (flags & NHR_COPY) {
833 		/* Copy destination if dst is non-zero */
834 		src = rt_key(rt);
835 		dst = info->rti_info[RTAX_DST];
836 		sa_len = src->sa_len;
837 		if (dst != NULL) {
838 			if (src->sa_len > dst->sa_len)
839 				return (ENOMEM);
840 			memcpy(dst, src, src->sa_len);
841 			info->rti_addrs |= RTA_DST;
842 		}
843 
844 		/* Copy mask if set && dst is non-zero */
845 		src = rt_mask(rt);
846 		dst = info->rti_info[RTAX_NETMASK];
847 		if (src != NULL && dst != NULL) {
848 
849 			/*
850 			 * Radix stores different value in sa_len,
851 			 * assume rt_mask() to have the same length
852 			 * as rt_key()
853 			 */
854 			if (sa_len > dst->sa_len)
855 				return (ENOMEM);
856 			memcpy(dst, src, src->sa_len);
857 			info->rti_addrs |= RTA_NETMASK;
858 		}
859 
860 		/* Copy gateway is set && dst is non-zero */
861 		src = rt->rt_gateway;
862 		dst = info->rti_info[RTAX_GATEWAY];
863 		if ((rt->rt_flags & RTF_GATEWAY) && src != NULL && dst != NULL){
864 			if (src->sa_len > dst->sa_len)
865 				return (ENOMEM);
866 			memcpy(dst, src, src->sa_len);
867 			info->rti_addrs |= RTA_GATEWAY;
868 		}
869 	} else {
870 		info->rti_info[RTAX_DST] = rt_key(rt);
871 		info->rti_addrs |= RTA_DST;
872 		if (rt_mask(rt) != NULL) {
873 			info->rti_info[RTAX_NETMASK] = rt_mask(rt);
874 			info->rti_addrs |= RTA_NETMASK;
875 		}
876 		if (rt->rt_flags & RTF_GATEWAY) {
877 			info->rti_info[RTAX_GATEWAY] = rt->rt_gateway;
878 			info->rti_addrs |= RTA_GATEWAY;
879 		}
880 	}
881 
882 	rmx = info->rti_rmx;
883 	if (rmx != NULL) {
884 		info->rti_mflags |= RTV_MTU;
885 		rmx->rmx_mtu = rt->rt_mtu;
886 	}
887 
888 	info->rti_flags = rt->rt_flags;
889 	info->rti_ifp = rt->rt_ifp;
890 	info->rti_ifa = rt->rt_ifa;
891 	if (flags & NHR_REF) {
892 		if_ref(info->rti_ifp);
893 		ifa_ref(info->rti_ifa);
894 	}
895 
896 	return (0);
897 }
898 
899 /*
900  * Lookups up route entry for @dst in RIB database for fib @fibnum.
901  * Exports entry data to @info using rt_exportinfo().
902  *
903  * If @flags contains NHR_REF, refcouting is performed on rt_ifp and rt_ifa.
904  * All references can be released later by calling rib_free_info().
905  *
906  * Returns 0 on success.
907  * Returns ENOENT for lookup failure, ENOMEM for export failure.
908  */
909 int
910 rib_lookup_info(uint32_t fibnum, const struct sockaddr *dst, uint32_t flags,
911     uint32_t flowid, struct rt_addrinfo *info)
912 {
913 	RIB_RLOCK_TRACKER;
914 	struct rib_head *rh;
915 	struct radix_node *rn;
916 	struct rtentry *rt;
917 	int error;
918 
919 	KASSERT((fibnum < rt_numfibs), ("rib_lookup_rte: bad fibnum"));
920 	rh = rt_tables_get_rnh(fibnum, dst->sa_family);
921 	if (rh == NULL)
922 		return (ENOENT);
923 
924 	RIB_RLOCK(rh);
925 	rn = rh->rnh_matchaddr(__DECONST(void *, dst), &rh->head);
926 	if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
927 		rt = RNTORT(rn);
928 		/* Ensure route & ifp is UP */
929 		if (RT_LINK_IS_UP(rt->rt_ifp)) {
930 			flags = (flags & NHR_REF) | NHR_COPY;
931 			error = rt_exportinfo(rt, info, flags);
932 			RIB_RUNLOCK(rh);
933 
934 			return (error);
935 		}
936 	}
937 	RIB_RUNLOCK(rh);
938 
939 	return (ENOENT);
940 }
941 
942 /*
943  * Releases all references acquired by rib_lookup_info() when
944  * called with NHR_REF flags.
945  */
946 void
947 rib_free_info(struct rt_addrinfo *info)
948 {
949 
950 	ifa_free(info->rti_ifa);
951 	if_rele(info->rti_ifp);
952 }
953 
954 /*
955  * Iterates over all existing fibs in system calling
956  *  @setwa_f function prior to traversing each fib.
957  *  Calls @wa_f function for each element in current fib.
958  * If af is not AF_UNSPEC, iterates over fibs in particular
959  * address family.
960  */
961 void
962 rt_foreach_fib_walk(int af, rt_setwarg_t *setwa_f, rt_walktree_f_t *wa_f,
963     void *arg)
964 {
965 	struct rib_head *rnh;
966 	uint32_t fibnum;
967 	int i;
968 
969 	for (fibnum = 0; fibnum < rt_numfibs; fibnum++) {
970 		/* Do we want some specific family? */
971 		if (af != AF_UNSPEC) {
972 			rnh = rt_tables_get_rnh(fibnum, af);
973 			if (rnh == NULL)
974 				continue;
975 			if (setwa_f != NULL)
976 				setwa_f(rnh, fibnum, af, arg);
977 
978 			RIB_WLOCK(rnh);
979 			rnh->rnh_walktree(&rnh->head, (walktree_f_t *)wa_f,arg);
980 			RIB_WUNLOCK(rnh);
981 			continue;
982 		}
983 
984 		for (i = 1; i <= AF_MAX; i++) {
985 			rnh = rt_tables_get_rnh(fibnum, i);
986 			if (rnh == NULL)
987 				continue;
988 			if (setwa_f != NULL)
989 				setwa_f(rnh, fibnum, i, arg);
990 
991 			RIB_WLOCK(rnh);
992 			rnh->rnh_walktree(&rnh->head, (walktree_f_t *)wa_f,arg);
993 			RIB_WUNLOCK(rnh);
994 		}
995 	}
996 }
997 
998 struct rt_delinfo
999 {
1000 	struct rt_addrinfo info;
1001 	struct rib_head *rnh;
1002 	struct rtentry *head;
1003 };
1004 
1005 /*
1006  * Conditionally unlinks @rn from radix tree based
1007  * on info data passed in @arg.
1008  */
1009 static int
1010 rt_checkdelroute(struct radix_node *rn, void *arg)
1011 {
1012 	struct rt_delinfo *di;
1013 	struct rt_addrinfo *info;
1014 	struct rtentry *rt;
1015 	int error;
1016 
1017 	di = (struct rt_delinfo *)arg;
1018 	rt = (struct rtentry *)rn;
1019 	info = &di->info;
1020 	error = 0;
1021 
1022 	info->rti_info[RTAX_DST] = rt_key(rt);
1023 	info->rti_info[RTAX_NETMASK] = rt_mask(rt);
1024 	info->rti_info[RTAX_GATEWAY] = rt->rt_gateway;
1025 
1026 	rt = rt_unlinkrte(di->rnh, info, &error);
1027 	if (rt == NULL) {
1028 		/* Either not allowed or not matched. Skip entry */
1029 		return (0);
1030 	}
1031 
1032 	/* Entry was unlinked. Add to the list and return */
1033 	rt->rt_chain = di->head;
1034 	di->head = rt;
1035 
1036 	return (0);
1037 }
1038 
1039 /*
1040  * Iterates over a routing table specified by @fibnum and @family and
1041  *  deletes elements marked by @filter_f.
1042  * @fibnum: rtable id
1043  * @family: AF_ address family
1044  * @filter_f: function returning non-zero value for items to delete
1045  * @arg: data to pass to the @filter_f function
1046  * @report: true if rtsock notification is needed.
1047  */
1048 void
1049 rib_walk_del(u_int fibnum, int family, rt_filter_f_t *filter_f, void *arg, bool report)
1050 {
1051 	struct rib_head *rnh;
1052 	struct rt_delinfo di;
1053 	struct rtentry *rt;
1054 
1055 	rnh = rt_tables_get_rnh(fibnum, family);
1056 	if (rnh == NULL)
1057 		return;
1058 
1059 	bzero(&di, sizeof(di));
1060 	di.info.rti_filter = filter_f;
1061 	di.info.rti_filterdata = arg;
1062 	di.rnh = rnh;
1063 
1064 	RIB_WLOCK(rnh);
1065 	rnh->rnh_walktree(&rnh->head, rt_checkdelroute, &di);
1066 	RIB_WUNLOCK(rnh);
1067 
1068 	if (di.head == NULL)
1069 		return;
1070 
1071 	/* We might have something to reclaim. */
1072 	while (di.head != NULL) {
1073 		rt = di.head;
1074 		di.head = rt->rt_chain;
1075 		rt->rt_chain = NULL;
1076 
1077 		/* TODO std rt -> rt_addrinfo export */
1078 		di.info.rti_info[RTAX_DST] = rt_key(rt);
1079 		di.info.rti_info[RTAX_NETMASK] = rt_mask(rt);
1080 
1081 		rt_notifydelete(rt, &di.info);
1082 
1083 		if (report)
1084 			rt_routemsg(RTM_DELETE, rt, rt->rt_ifp, 0, fibnum);
1085 		RTFREE_LOCKED(rt);
1086 	}
1087 }
1088 
1089 /*
1090  * Iterates over all existing fibs in system and deletes each element
1091  *  for which @filter_f function returns non-zero value.
1092  * If @family is not AF_UNSPEC, iterates over fibs in particular
1093  * address family.
1094  */
1095 void
1096 rt_foreach_fib_walk_del(int family, rt_filter_f_t *filter_f, void *arg)
1097 {
1098 	u_int fibnum;
1099 	int i, start, end;
1100 
1101 	for (fibnum = 0; fibnum < rt_numfibs; fibnum++) {
1102 		/* Do we want some specific family? */
1103 		if (family != AF_UNSPEC) {
1104 			start = family;
1105 			end = family;
1106 		} else {
1107 			start = 1;
1108 			end = AF_MAX;
1109 		}
1110 
1111 		for (i = start; i <= end; i++) {
1112 			if (rt_tables_get_rnh(fibnum, i) == NULL)
1113 				continue;
1114 
1115 			rib_walk_del(fibnum, i, filter_f, arg, 0);
1116 		}
1117 	}
1118 }
1119 
1120 /*
1121  * Delete Routes for a Network Interface
1122  *
1123  * Called for each routing entry via the rnh->rnh_walktree() call above
1124  * to delete all route entries referencing a detaching network interface.
1125  *
1126  * Arguments:
1127  *	rt	pointer to rtentry
1128  *	nh	pointer to nhop
1129  *	arg	argument passed to rnh->rnh_walktree() - detaching interface
1130  *
1131  * Returns:
1132  *	0	successful
1133  *	errno	failed - reason indicated
1134  */
1135 static int
1136 rt_ifdelroute(const struct rtentry *rt, const struct nhop_object *nh, void *arg)
1137 {
1138 	struct ifnet	*ifp = arg;
1139 
1140 	if (nh->nh_ifp != ifp)
1141 		return (0);
1142 
1143 	/*
1144 	 * Protect (sorta) against walktree recursion problems
1145 	 * with cloned routes
1146 	 */
1147 	if ((rt->rt_flags & RTF_UP) == 0)
1148 		return (0);
1149 
1150 	return (1);
1151 }
1152 
1153 /*
1154  * Delete all remaining routes using this interface
1155  * Unfortuneatly the only way to do this is to slog through
1156  * the entire routing table looking for routes which point
1157  * to this interface...oh well...
1158  */
1159 void
1160 rt_flushifroutes_af(struct ifnet *ifp, int af)
1161 {
1162 	KASSERT((af >= 1 && af <= AF_MAX), ("%s: af %d not >= 1 and <= %d",
1163 	    __func__, af, AF_MAX));
1164 
1165 	rt_foreach_fib_walk_del(af, rt_ifdelroute, ifp);
1166 }
1167 
1168 void
1169 rt_flushifroutes(struct ifnet *ifp)
1170 {
1171 
1172 	rt_foreach_fib_walk_del(AF_UNSPEC, rt_ifdelroute, ifp);
1173 }
1174 
1175 /*
1176  * Conditionally unlinks rtentry matching data inside @info from @rnh.
1177  * Returns unlinked, locked and referenced @rtentry on success,
1178  * Returns NULL and sets @perror to:
1179  * ESRCH - if prefix was not found,
1180  * EADDRINUSE - if trying to delete PINNED route without appropriate flag.
1181  * ENOENT - if supplied filter function returned 0 (not matched).
1182  */
1183 static struct rtentry *
1184 rt_unlinkrte(struct rib_head *rnh, struct rt_addrinfo *info, int *perror)
1185 {
1186 	struct sockaddr *dst, *netmask;
1187 	struct rtentry *rt;
1188 	struct radix_node *rn;
1189 
1190 	dst = info->rti_info[RTAX_DST];
1191 	netmask = info->rti_info[RTAX_NETMASK];
1192 
1193 	rt = (struct rtentry *)rnh->rnh_lookup(dst, netmask, &rnh->head);
1194 	if (rt == NULL) {
1195 		*perror = ESRCH;
1196 		return (NULL);
1197 	}
1198 
1199 	if ((info->rti_flags & RTF_PINNED) == 0) {
1200 		/* Check if target route can be deleted */
1201 		if (rt->rt_flags & RTF_PINNED) {
1202 			*perror = EADDRINUSE;
1203 			return (NULL);
1204 		}
1205 	}
1206 
1207 	if (info->rti_filter != NULL) {
1208 		if (info->rti_filter(rt, rt->rt_nhop, info->rti_filterdata)==0){
1209 			/* Not matched */
1210 			*perror = ENOENT;
1211 			return (NULL);
1212 		}
1213 
1214 		/*
1215 		 * Filter function requested rte deletion.
1216 		 * Ease the caller work by filling in remaining info
1217 		 * from that particular entry.
1218 		 */
1219 		info->rti_info[RTAX_GATEWAY] = rt->rt_gateway;
1220 	}
1221 
1222 	/*
1223 	 * Remove the item from the tree and return it.
1224 	 * Complain if it is not there and do no more processing.
1225 	 */
1226 	*perror = ESRCH;
1227 #ifdef RADIX_MPATH
1228 	if (rt_mpath_capable(rnh))
1229 		rn = rt_mpath_unlink(rnh, info, rt, perror);
1230 	else
1231 #endif
1232 	rn = rnh->rnh_deladdr(dst, netmask, &rnh->head);
1233 	if (rn == NULL)
1234 		return (NULL);
1235 
1236 	if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT))
1237 		panic ("rtrequest delete");
1238 
1239 	rt = RNTORT(rn);
1240 	RT_LOCK(rt);
1241 	RT_ADDREF(rt);
1242 	rt->rt_flags &= ~RTF_UP;
1243 
1244 	*perror = 0;
1245 
1246 	return (rt);
1247 }
1248 
1249 static void
1250 rt_notifydelete(struct rtentry *rt, struct rt_addrinfo *info)
1251 {
1252 	struct ifaddr *ifa;
1253 
1254 	/*
1255 	 * give the protocol a chance to keep things in sync.
1256 	 */
1257 	ifa = rt->rt_ifa;
1258 	if (ifa != NULL && ifa->ifa_rtrequest != NULL)
1259 		ifa->ifa_rtrequest(RTM_DELETE, rt, info);
1260 
1261 	/*
1262 	 * One more rtentry floating around that is not
1263 	 * linked to the routing table. rttrash will be decremented
1264 	 * when RTFREE(rt) is eventually called.
1265 	 */
1266 	V_rttrash++;
1267 }
1268 
1269 
1270 /*
1271  * These (questionable) definitions of apparent local variables apply
1272  * to the next two functions.  XXXXXX!!!
1273  */
1274 #define	dst	info->rti_info[RTAX_DST]
1275 #define	gateway	info->rti_info[RTAX_GATEWAY]
1276 #define	netmask	info->rti_info[RTAX_NETMASK]
1277 #define	ifaaddr	info->rti_info[RTAX_IFA]
1278 #define	ifpaddr	info->rti_info[RTAX_IFP]
1279 #define	flags	info->rti_flags
1280 
1281 /*
1282  * Look up rt_addrinfo for a specific fib.  Note that if rti_ifa is defined,
1283  * it will be referenced so the caller must free it.
1284  *
1285  * Assume basic consistency checks are executed by callers:
1286  * RTAX_DST exists, if RTF_GATEWAY is set, RTAX_GATEWAY exists as well.
1287  */
1288 int
1289 rt_getifa_fib(struct rt_addrinfo *info, u_int fibnum)
1290 {
1291 	struct epoch_tracker et;
1292 	int needref, error;
1293 
1294 	/*
1295 	 * ifp may be specified by sockaddr_dl
1296 	 * when protocol address is ambiguous.
1297 	 */
1298 	error = 0;
1299 	needref = (info->rti_ifa == NULL);
1300 	NET_EPOCH_ENTER(et);
1301 
1302 	/* If we have interface specified by the ifindex in the address, use it */
1303 	if (info->rti_ifp == NULL && ifpaddr != NULL &&
1304 	    ifpaddr->sa_family == AF_LINK) {
1305 	    const struct sockaddr_dl *sdl = (const struct sockaddr_dl *)ifpaddr;
1306 	    if (sdl->sdl_index != 0)
1307 		    info->rti_ifp = ifnet_byindex(sdl->sdl_index);
1308 	}
1309 	/*
1310 	 * If we have source address specified, try to find it
1311 	 * TODO: avoid enumerating all ifas on all interfaces.
1312 	 */
1313 	if (info->rti_ifa == NULL && ifaaddr != NULL)
1314 		info->rti_ifa = ifa_ifwithaddr(ifaaddr);
1315 	if (info->rti_ifa == NULL) {
1316 		struct sockaddr *sa;
1317 
1318 		/*
1319 		 * Most common use case for the userland-supplied routes.
1320 		 *
1321 		 * Choose sockaddr to select ifa.
1322 		 * -- if ifp is set --
1323 		 * Order of preference:
1324 		 * 1) IFA address
1325 		 * 2) gateway address
1326 		 *   Note: for interface routes link-level gateway address
1327 		 *     is specified to indicate the interface index without
1328 		 *     specifying RTF_GATEWAY. In this case, ignore gateway
1329 		 *   Note: gateway AF may be different from dst AF. In this case,
1330 		 *   ignore gateway
1331 		 * 3) final destination.
1332 		 * 4) if all of these fails, try to get at least link-level ifa.
1333 		 * -- else --
1334 		 * try to lookup gateway or dst in the routing table to get ifa
1335 		 */
1336 		if (info->rti_info[RTAX_IFA] != NULL)
1337 			sa = info->rti_info[RTAX_IFA];
1338 		else if ((info->rti_flags & RTF_GATEWAY) != 0 &&
1339 		    gateway->sa_family == dst->sa_family)
1340 			sa = gateway;
1341 		else
1342 			sa = dst;
1343 		if (info->rti_ifp != NULL) {
1344 			info->rti_ifa = ifaof_ifpforaddr(sa, info->rti_ifp);
1345 			/* Case 4 */
1346 			if (info->rti_ifa == NULL && gateway != NULL)
1347 				info->rti_ifa = ifaof_ifpforaddr(gateway, info->rti_ifp);
1348 		} else if (dst != NULL && gateway != NULL)
1349 			info->rti_ifa = ifa_ifwithroute(flags, dst, gateway,
1350 							fibnum);
1351 		else if (sa != NULL)
1352 			info->rti_ifa = ifa_ifwithroute(flags, sa, sa,
1353 							fibnum);
1354 	}
1355 	if (needref && info->rti_ifa != NULL) {
1356 		if (info->rti_ifp == NULL)
1357 			info->rti_ifp = info->rti_ifa->ifa_ifp;
1358 		ifa_ref(info->rti_ifa);
1359 	} else
1360 		error = ENETUNREACH;
1361 	NET_EPOCH_EXIT(et);
1362 	return (error);
1363 }
1364 
1365 static int
1366 if_updatemtu_cb(struct radix_node *rn, void *arg)
1367 {
1368 	struct rtentry *rt;
1369 	struct if_mtuinfo *ifmtu;
1370 
1371 	rt = (struct rtentry *)rn;
1372 	ifmtu = (struct if_mtuinfo *)arg;
1373 
1374 	if (rt->rt_ifp != ifmtu->ifp)
1375 		return (0);
1376 
1377 	if (rt->rt_mtu >= ifmtu->mtu) {
1378 		/* We have to decrease mtu regardless of flags */
1379 		rt->rt_mtu = ifmtu->mtu;
1380 		return (0);
1381 	}
1382 
1383 	/*
1384 	 * New MTU is bigger. Check if are allowed to alter it
1385 	 */
1386 	if ((rt->rt_flags & (RTF_FIXEDMTU | RTF_GATEWAY | RTF_HOST)) != 0) {
1387 
1388 		/*
1389 		 * Skip routes with user-supplied MTU and
1390 		 * non-interface routes
1391 		 */
1392 		return (0);
1393 	}
1394 
1395 	/* We are safe to update route MTU */
1396 	rt->rt_mtu = ifmtu->mtu;
1397 
1398 	return (0);
1399 }
1400 
1401 void
1402 rt_updatemtu(struct ifnet *ifp)
1403 {
1404 	struct if_mtuinfo ifmtu;
1405 	struct rib_head *rnh;
1406 	int i, j;
1407 
1408 	ifmtu.ifp = ifp;
1409 
1410 	/*
1411 	 * Try to update rt_mtu for all routes using this interface
1412 	 * Unfortunately the only way to do this is to traverse all
1413 	 * routing tables in all fibs/domains.
1414 	 */
1415 	for (i = 1; i <= AF_MAX; i++) {
1416 		ifmtu.mtu = if_getmtu_family(ifp, i);
1417 		for (j = 0; j < rt_numfibs; j++) {
1418 			rnh = rt_tables_get_rnh(j, i);
1419 			if (rnh == NULL)
1420 				continue;
1421 			RIB_WLOCK(rnh);
1422 			rnh->rnh_walktree(&rnh->head, if_updatemtu_cb, &ifmtu);
1423 			RIB_WUNLOCK(rnh);
1424 			nhops_update_ifmtu(rnh, ifp, ifmtu.mtu);
1425 		}
1426 	}
1427 }
1428 
1429 
1430 #if 0
1431 int p_sockaddr(char *buf, int buflen, struct sockaddr *s);
1432 int rt_print(char *buf, int buflen, struct rtentry *rt);
1433 
1434 int
1435 p_sockaddr(char *buf, int buflen, struct sockaddr *s)
1436 {
1437 	void *paddr = NULL;
1438 
1439 	switch (s->sa_family) {
1440 	case AF_INET:
1441 		paddr = &((struct sockaddr_in *)s)->sin_addr;
1442 		break;
1443 	case AF_INET6:
1444 		paddr = &((struct sockaddr_in6 *)s)->sin6_addr;
1445 		break;
1446 	}
1447 
1448 	if (paddr == NULL)
1449 		return (0);
1450 
1451 	if (inet_ntop(s->sa_family, paddr, buf, buflen) == NULL)
1452 		return (0);
1453 
1454 	return (strlen(buf));
1455 }
1456 
1457 int
1458 rt_print(char *buf, int buflen, struct rtentry *rt)
1459 {
1460 	struct sockaddr *addr, *mask;
1461 	int i = 0;
1462 
1463 	addr = rt_key(rt);
1464 	mask = rt_mask(rt);
1465 
1466 	i = p_sockaddr(buf, buflen, addr);
1467 	if (!(rt->rt_flags & RTF_HOST)) {
1468 		buf[i++] = '/';
1469 		i += p_sockaddr(buf + i, buflen - i, mask);
1470 	}
1471 
1472 	if (rt->rt_flags & RTF_GATEWAY) {
1473 		buf[i++] = '>';
1474 		i += p_sockaddr(buf + i, buflen - i, rt->rt_gateway);
1475 	}
1476 
1477 	return (i);
1478 }
1479 #endif
1480 
1481 #ifdef RADIX_MPATH
1482 /*
1483  * Deletes key for single-path routes, unlinks rtentry with
1484  * gateway specified in @info from multi-path routes.
1485  *
1486  * Returnes unlinked entry. In case of failure, returns NULL
1487  * and sets @perror to ESRCH.
1488  */
1489 static struct radix_node *
1490 rt_mpath_unlink(struct rib_head *rnh, struct rt_addrinfo *info,
1491     struct rtentry *rto, int *perror)
1492 {
1493 	/*
1494 	 * if we got multipath routes, we require users to specify
1495 	 * a matching RTAX_GATEWAY.
1496 	 */
1497 	struct rtentry *rt; // *rto = NULL;
1498 	struct radix_node *rn;
1499 	struct sockaddr *gw;
1500 
1501 	gw = info->rti_info[RTAX_GATEWAY];
1502 	rt = rt_mpath_matchgate(rto, gw);
1503 	if (rt == NULL) {
1504 		*perror = ESRCH;
1505 		return (NULL);
1506 	}
1507 
1508 	/*
1509 	 * this is the first entry in the chain
1510 	 */
1511 	if (rto == rt) {
1512 		rn = rn_mpath_next((struct radix_node *)rt);
1513 		/*
1514 		 * there is another entry, now it's active
1515 		 */
1516 		if (rn) {
1517 			rto = RNTORT(rn);
1518 			RT_LOCK(rto);
1519 			rto->rt_flags |= RTF_UP;
1520 			RT_UNLOCK(rto);
1521 		} else if (rt->rt_flags & RTF_GATEWAY) {
1522 			/*
1523 			 * For gateway routes, we need to
1524 			 * make sure that we we are deleting
1525 			 * the correct gateway.
1526 			 * rt_mpath_matchgate() does not
1527 			 * check the case when there is only
1528 			 * one route in the chain.
1529 			 */
1530 			if (gw &&
1531 			    (rt->rt_gateway->sa_len != gw->sa_len ||
1532 				memcmp(rt->rt_gateway, gw, gw->sa_len))) {
1533 				*perror = ESRCH;
1534 				return (NULL);
1535 			}
1536 		}
1537 
1538 		/*
1539 		 * use the normal delete code to remove
1540 		 * the first entry
1541 		 */
1542 		rn = rnh->rnh_deladdr(dst, netmask, &rnh->head);
1543 		*perror = 0;
1544 		return (rn);
1545 	}
1546 
1547 	/*
1548 	 * if the entry is 2nd and on up
1549 	 */
1550 	if (rt_mpath_deldup(rto, rt) == 0)
1551 		panic ("rtrequest1: rt_mpath_deldup");
1552 	*perror = 0;
1553 	rn = (struct radix_node *)rt;
1554 	return (rn);
1555 }
1556 #endif
1557 
1558 #undef dst
1559 #undef gateway
1560 #undef netmask
1561 #undef ifaaddr
1562 #undef ifpaddr
1563 #undef flags
1564 
1565 int
1566 rtrequest1_fib(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt,
1567 				u_int fibnum)
1568 {
1569 	struct epoch_tracker et;
1570 	const struct sockaddr *dst;
1571 	struct rib_head *rnh;
1572 	int error;
1573 
1574 	KASSERT((fibnum < rt_numfibs), ("rtrequest1_fib: bad fibnum"));
1575 	KASSERT((info->rti_flags & RTF_RNH_LOCKED) == 0, ("rtrequest1_fib: locked"));
1576 
1577 	dst = info->rti_info[RTAX_DST];
1578 
1579 	switch (dst->sa_family) {
1580 	case AF_INET6:
1581 	case AF_INET:
1582 		/* We support multiple FIBs. */
1583 		break;
1584 	default:
1585 		fibnum = RT_DEFAULT_FIB;
1586 		break;
1587 	}
1588 
1589 	/*
1590 	 * Find the correct routing tree to use for this Address Family
1591 	 */
1592 	rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
1593 	if (rnh == NULL)
1594 		return (EAFNOSUPPORT);
1595 
1596 	/*
1597 	 * If we are adding a host route then we don't want to put
1598 	 * a netmask in the tree, nor do we want to clone it.
1599 	 */
1600 	if (info->rti_flags & RTF_HOST)
1601 		info->rti_info[RTAX_NETMASK] = NULL;
1602 
1603 	error = 0;
1604 	switch (req) {
1605 	case RTM_DELETE:
1606 		error = del_route(rnh, info, ret_nrt);
1607 		break;
1608 	case RTM_RESOLVE:
1609 		/*
1610 		 * resolve was only used for route cloning
1611 		 * here for compat
1612 		 */
1613 		break;
1614 	case RTM_ADD:
1615 		error = add_route(rnh, info, ret_nrt);
1616 		break;
1617 	case RTM_CHANGE:
1618 		NET_EPOCH_ENTER(et);
1619 		RIB_WLOCK(rnh);
1620 		error = change_route(rnh, info, ret_nrt);
1621 		RIB_WUNLOCK(rnh);
1622 		NET_EPOCH_EXIT(et);
1623 		break;
1624 	default:
1625 		error = EOPNOTSUPP;
1626 	}
1627 
1628 	return (error);
1629 }
1630 
1631 static int
1632 add_route(struct rib_head *rnh, struct rt_addrinfo *info,
1633     struct rtentry **ret_nrt)
1634 {
1635 	struct sockaddr *dst, *ndst, *gateway, *netmask;
1636 	struct rtentry *rt, *rt_old;
1637 	struct nhop_object *nh;
1638 	struct radix_node *rn;
1639 	struct ifaddr *ifa;
1640 	int error, flags;
1641 	struct epoch_tracker et;
1642 
1643 	dst = info->rti_info[RTAX_DST];
1644 	gateway = info->rti_info[RTAX_GATEWAY];
1645 	netmask = info->rti_info[RTAX_NETMASK];
1646 	flags = info->rti_flags;
1647 
1648 	if ((flags & RTF_GATEWAY) && !gateway)
1649 		return (EINVAL);
1650 	if (dst && gateway && (dst->sa_family != gateway->sa_family) &&
1651 	    (gateway->sa_family != AF_UNSPEC) && (gateway->sa_family != AF_LINK))
1652 		return (EINVAL);
1653 
1654 	if (info->rti_ifa == NULL) {
1655 		error = rt_getifa_fib(info, rnh->rib_fibnum);
1656 		if (error)
1657 			return (error);
1658 	} else {
1659 		ifa_ref(info->rti_ifa);
1660 	}
1661 
1662 	NET_EPOCH_ENTER(et);
1663 	error = nhop_create_from_info(rnh, info, &nh);
1664 	NET_EPOCH_EXIT(et);
1665 	if (error != 0) {
1666 		ifa_free(info->rti_ifa);
1667 		return (error);
1668 	}
1669 
1670 	rt = uma_zalloc(V_rtzone, M_NOWAIT);
1671 	if (rt == NULL) {
1672 		ifa_free(info->rti_ifa);
1673 		nhop_free(nh);
1674 		return (ENOBUFS);
1675 	}
1676 	rt->rt_flags = RTF_UP | flags;
1677 	rt->rt_fibnum = rnh->rib_fibnum;
1678 	rt->rt_nhop = nh;
1679 	/*
1680 	 * Add the gateway. Possibly re-malloc-ing the storage for it.
1681 	 */
1682 	if ((error = rt_setgate(rt, dst, gateway)) != 0) {
1683 		ifa_free(info->rti_ifa);
1684 		nhop_free(nh);
1685 		uma_zfree(V_rtzone, rt);
1686 		return (error);
1687 	}
1688 
1689 	/*
1690 	 * point to the (possibly newly malloc'd) dest address.
1691 	 */
1692 	ndst = (struct sockaddr *)rt_key(rt);
1693 
1694 	/*
1695 	 * make sure it contains the value we want (masked if needed).
1696 	 */
1697 	if (netmask) {
1698 		rt_maskedcopy(dst, ndst, netmask);
1699 	} else
1700 		bcopy(dst, ndst, dst->sa_len);
1701 
1702 	/*
1703 	 * We use the ifa reference returned by rt_getifa_fib().
1704 	 * This moved from below so that rnh->rnh_addaddr() can
1705 	 * examine the ifa and  ifa->ifa_ifp if it so desires.
1706 	 */
1707 	ifa = info->rti_ifa;
1708 	rt->rt_ifa = ifa;
1709 	rt->rt_ifp = ifa->ifa_ifp;
1710 	rt->rt_weight = 1;
1711 
1712 	rt_setmetrics(info, rt);
1713 
1714 	RIB_WLOCK(rnh);
1715 	RT_LOCK(rt);
1716 #ifdef RADIX_MPATH
1717 	/* do not permit exactly the same dst/mask/gw pair */
1718 	if (rt_mpath_capable(rnh) &&
1719 		rt_mpath_conflict(rnh, rt, netmask)) {
1720 		RIB_WUNLOCK(rnh);
1721 
1722 		ifa_free(rt->rt_ifa);
1723 		R_Free(rt_key(rt));
1724 		nhop_free(nh);
1725 		uma_zfree(V_rtzone, rt);
1726 		return (EEXIST);
1727 	}
1728 #endif
1729 
1730 	/* XXX mtu manipulation will be done in rnh_addaddr -- itojun */
1731 	rn = rnh->rnh_addaddr(ndst, netmask, &rnh->head, rt->rt_nodes);
1732 
1733 	if (rn != NULL && rt->rt_expire > 0)
1734 		tmproutes_update(rnh, rt);
1735 
1736 	rt_old = NULL;
1737 	if (rn == NULL && (info->rti_flags & RTF_PINNED) != 0) {
1738 
1739 		/*
1740 		 * Force removal and re-try addition
1741 		 * TODO: better multipath&pinned support
1742 		 */
1743 		struct sockaddr *info_dst = info->rti_info[RTAX_DST];
1744 		info->rti_info[RTAX_DST] = ndst;
1745 		/* Do not delete existing PINNED(interface) routes */
1746 		info->rti_flags &= ~RTF_PINNED;
1747 		rt_old = rt_unlinkrte(rnh, info, &error);
1748 		info->rti_flags |= RTF_PINNED;
1749 		info->rti_info[RTAX_DST] = info_dst;
1750 		if (rt_old != NULL)
1751 			rn = rnh->rnh_addaddr(ndst, netmask, &rnh->head,
1752 			    rt->rt_nodes);
1753 	}
1754 	RIB_WUNLOCK(rnh);
1755 
1756 	if (rt_old != NULL)
1757 		RT_UNLOCK(rt_old);
1758 
1759 	/*
1760 	 * If it still failed to go into the tree,
1761 	 * then un-make it (this should be a function)
1762 	 */
1763 	if (rn == NULL) {
1764 		ifa_free(rt->rt_ifa);
1765 		R_Free(rt_key(rt));
1766 		nhop_free(nh);
1767 		uma_zfree(V_rtzone, rt);
1768 		return (EEXIST);
1769 	}
1770 
1771 	if (rt_old != NULL) {
1772 		rt_notifydelete(rt_old, info);
1773 		RTFREE(rt_old);
1774 	}
1775 
1776 	/*
1777 	 * If this protocol has something to add to this then
1778 	 * allow it to do that as well.
1779 	 */
1780 	if (ifa->ifa_rtrequest)
1781 		ifa->ifa_rtrequest(RTM_ADD, rt, info);
1782 
1783 	/*
1784 	 * actually return a resultant rtentry and
1785 	 * give the caller a single reference.
1786 	 */
1787 	if (ret_nrt) {
1788 		*ret_nrt = rt;
1789 		RT_ADDREF(rt);
1790 	}
1791 	rnh->rnh_gen++;		/* Routing table updated */
1792 	RT_UNLOCK(rt);
1793 
1794 	return (0);
1795 }
1796 
1797 static int
1798 del_route(struct rib_head *rnh, struct rt_addrinfo *info,
1799     struct rtentry **ret_nrt)
1800 {
1801 	struct sockaddr *dst, *netmask;
1802 	struct sockaddr_storage mdst;
1803 	struct rtentry *rt;
1804 	int error;
1805 
1806 	dst = info->rti_info[RTAX_DST];
1807 	netmask = info->rti_info[RTAX_NETMASK];
1808 
1809 	if (netmask) {
1810 		if (dst->sa_len > sizeof(mdst))
1811 			return (EINVAL);
1812 		rt_maskedcopy(dst, (struct sockaddr *)&mdst, netmask);
1813 		dst = (struct sockaddr *)&mdst;
1814 	}
1815 
1816 	RIB_WLOCK(rnh);
1817 	rt = rt_unlinkrte(rnh, info, &error);
1818 	RIB_WUNLOCK(rnh);
1819 	if (error != 0)
1820 		return (error);
1821 
1822 	rt_notifydelete(rt, info);
1823 
1824 	/*
1825 	 * If the caller wants it, then it can have it,
1826 	 * but it's up to it to free the rtentry as we won't be
1827 	 * doing it.
1828 	 */
1829 	if (ret_nrt) {
1830 		*ret_nrt = rt;
1831 		RT_UNLOCK(rt);
1832 	} else
1833 		RTFREE_LOCKED(rt);
1834 
1835 	return (0);
1836 }
1837 
1838 static int
1839 change_route(struct rib_head *rnh, struct rt_addrinfo *info,
1840     struct rtentry **ret_nrt)
1841 {
1842 	struct rtentry *rt = NULL;
1843 	int error = 0;
1844 	int free_ifa = 0;
1845 	int family, mtu;
1846 	struct nhop_object *nh;
1847 	struct if_mtuinfo ifmtu;
1848 
1849 	RIB_WLOCK_ASSERT(rnh);
1850 
1851 	rt = (struct rtentry *)rnh->rnh_lookup(info->rti_info[RTAX_DST],
1852 	    info->rti_info[RTAX_NETMASK], &rnh->head);
1853 
1854 	if (rt == NULL)
1855 		return (ESRCH);
1856 
1857 #ifdef RADIX_MPATH
1858 	/*
1859 	 * If we got multipath routes,
1860 	 * we require users to specify a matching RTAX_GATEWAY.
1861 	 */
1862 	if (rt_mpath_capable(rnh)) {
1863 		rt = rt_mpath_matchgate(rt, info->rti_info[RTAX_GATEWAY]);
1864 		if (rt == NULL)
1865 			return (ESRCH);
1866 	}
1867 #endif
1868 
1869 	nh = NULL;
1870 	RT_LOCK(rt);
1871 
1872 	rt_setmetrics(info, rt);
1873 
1874 	/*
1875 	 * New gateway could require new ifaddr, ifp;
1876 	 * flags may also be different; ifp may be specified
1877 	 * by ll sockaddr when protocol address is ambiguous
1878 	 */
1879 	if (((rt->rt_flags & RTF_GATEWAY) &&
1880 	    info->rti_info[RTAX_GATEWAY] != NULL) ||
1881 	    info->rti_info[RTAX_IFP] != NULL ||
1882 	    (info->rti_info[RTAX_IFA] != NULL &&
1883 	     !sa_equal(info->rti_info[RTAX_IFA], rt->rt_ifa->ifa_addr))) {
1884 		/*
1885 		 * XXX: Temporarily set RTF_RNH_LOCKED flag in the rti_flags
1886 		 *	to avoid rlock in the ifa_ifwithroute().
1887 		 */
1888 		info->rti_flags |= RTF_RNH_LOCKED;
1889 		error = rt_getifa_fib(info, rnh->rib_fibnum);
1890 		info->rti_flags &= ~RTF_RNH_LOCKED;
1891 		if (info->rti_ifa != NULL)
1892 			free_ifa = 1;
1893 
1894 		if (error != 0)
1895 			goto bad;
1896 	}
1897 
1898 	error = nhop_create_from_nhop(rnh, rt->rt_nhop, info, &nh);
1899 	if (error != 0)
1900 		goto bad;
1901 
1902 	/* Check if outgoing interface has changed */
1903 	if (info->rti_ifa != NULL && info->rti_ifa != rt->rt_ifa &&
1904 	    rt->rt_ifa != NULL) {
1905 		if (rt->rt_ifa->ifa_rtrequest != NULL)
1906 			rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt, info);
1907 		ifa_free(rt->rt_ifa);
1908 		rt->rt_ifa = NULL;
1909 	}
1910 	/* Update gateway address */
1911 	if (info->rti_info[RTAX_GATEWAY] != NULL) {
1912 		error = rt_setgate(rt, rt_key(rt), info->rti_info[RTAX_GATEWAY]);
1913 		if (error != 0)
1914 			goto bad;
1915 
1916 		rt->rt_flags &= ~RTF_GATEWAY;
1917 		rt->rt_flags |= (RTF_GATEWAY & info->rti_flags);
1918 	}
1919 
1920 	if (info->rti_ifa != NULL && info->rti_ifa != rt->rt_ifa) {
1921 		ifa_ref(info->rti_ifa);
1922 		rt->rt_ifa = info->rti_ifa;
1923 		rt->rt_ifp = info->rti_ifp;
1924 	}
1925 	/* Allow some flags to be toggled on change. */
1926 	rt->rt_flags &= ~RTF_FMASK;
1927 	rt->rt_flags |= info->rti_flags & RTF_FMASK;
1928 
1929 	if (rt->rt_ifa && rt->rt_ifa->ifa_rtrequest != NULL)
1930 	       rt->rt_ifa->ifa_rtrequest(RTM_ADD, rt, info);
1931 
1932 	/* Alter route MTU if necessary */
1933 	if (rt->rt_ifp != NULL) {
1934 		family = info->rti_info[RTAX_DST]->sa_family;
1935 		mtu = if_getmtu_family(rt->rt_ifp, family);
1936 		/* Set default MTU */
1937 		if (rt->rt_mtu == 0)
1938 			rt->rt_mtu = mtu;
1939 		if (rt->rt_mtu != mtu) {
1940 			/* Check if we really need to update */
1941 			ifmtu.ifp = rt->rt_ifp;
1942 			ifmtu.mtu = mtu;
1943 			if_updatemtu_cb(rt->rt_nodes, &ifmtu);
1944 		}
1945 	}
1946 
1947 	/* Update nexthop */
1948 	nhop_free(rt->rt_nhop);
1949 	rt->rt_nhop = nh;
1950 	nh = NULL;
1951 
1952 	/*
1953 	 * This route change may have modified the route's gateway.  In that
1954 	 * case, any inpcbs that have cached this route need to invalidate their
1955 	 * llentry cache.
1956 	 */
1957 	rnh->rnh_gen++;
1958 
1959 	if (ret_nrt) {
1960 		*ret_nrt = rt;
1961 		RT_ADDREF(rt);
1962 	}
1963 bad:
1964 	RT_UNLOCK(rt);
1965 	if (nh != NULL)
1966 		nhop_free(nh);
1967 	if (free_ifa != 0) {
1968 		ifa_free(info->rti_ifa);
1969 		info->rti_ifa = NULL;
1970 	}
1971 	return (error);
1972 }
1973 
1974 static void
1975 rt_setmetrics(const struct rt_addrinfo *info, struct rtentry *rt)
1976 {
1977 
1978 	if (info->rti_mflags & RTV_MTU) {
1979 		if (info->rti_rmx->rmx_mtu != 0) {
1980 
1981 			/*
1982 			 * MTU was explicitly provided by user.
1983 			 * Keep it.
1984 			 */
1985 			rt->rt_flags |= RTF_FIXEDMTU;
1986 		} else {
1987 
1988 			/*
1989 			 * User explicitly sets MTU to 0.
1990 			 * Assume rollback to default.
1991 			 */
1992 			rt->rt_flags &= ~RTF_FIXEDMTU;
1993 		}
1994 		rt->rt_mtu = info->rti_rmx->rmx_mtu;
1995 	}
1996 	if (info->rti_mflags & RTV_WEIGHT)
1997 		rt->rt_weight = info->rti_rmx->rmx_weight;
1998 	/* Kernel -> userland timebase conversion. */
1999 	if (info->rti_mflags & RTV_EXPIRE)
2000 		rt->rt_expire = info->rti_rmx->rmx_expire ?
2001 		    info->rti_rmx->rmx_expire - time_second + time_uptime : 0;
2002 }
2003 
2004 int
2005 rt_setgate(struct rtentry *rt, struct sockaddr *dst, struct sockaddr *gate)
2006 {
2007 	/* XXX dst may be overwritten, can we move this to below */
2008 	int dlen = SA_SIZE(dst), glen = SA_SIZE(gate);
2009 
2010 	/*
2011 	 * Prepare to store the gateway in rt->rt_gateway.
2012 	 * Both dst and gateway are stored one after the other in the same
2013 	 * malloc'd chunk. If we have room, we can reuse the old buffer,
2014 	 * rt_gateway already points to the right place.
2015 	 * Otherwise, malloc a new block and update the 'dst' address.
2016 	 */
2017 	if (rt->rt_gateway == NULL || glen > SA_SIZE(rt->rt_gateway)) {
2018 		caddr_t new;
2019 
2020 		R_Malloc(new, caddr_t, dlen + glen);
2021 		if (new == NULL)
2022 			return ENOBUFS;
2023 		/*
2024 		 * XXX note, we copy from *dst and not *rt_key(rt) because
2025 		 * rt_setgate() can be called to initialize a newly
2026 		 * allocated route entry, in which case rt_key(rt) == NULL
2027 		 * (and also rt->rt_gateway == NULL).
2028 		 * Free()/free() handle a NULL argument just fine.
2029 		 */
2030 		bcopy(dst, new, dlen);
2031 		R_Free(rt_key(rt));	/* free old block, if any */
2032 		rt_key(rt) = (struct sockaddr *)new;
2033 		rt->rt_gateway = (struct sockaddr *)(new + dlen);
2034 	}
2035 
2036 	/*
2037 	 * Copy the new gateway value into the memory chunk.
2038 	 */
2039 	bcopy(gate, rt->rt_gateway, glen);
2040 
2041 	return (0);
2042 }
2043 
2044 void
2045 rt_maskedcopy(struct sockaddr *src, struct sockaddr *dst, struct sockaddr *netmask)
2046 {
2047 	u_char *cp1 = (u_char *)src;
2048 	u_char *cp2 = (u_char *)dst;
2049 	u_char *cp3 = (u_char *)netmask;
2050 	u_char *cplim = cp2 + *cp3;
2051 	u_char *cplim2 = cp2 + *cp1;
2052 
2053 	*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
2054 	cp3 += 2;
2055 	if (cplim > cplim2)
2056 		cplim = cplim2;
2057 	while (cp2 < cplim)
2058 		*cp2++ = *cp1++ & *cp3++;
2059 	if (cp2 < cplim2)
2060 		bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2));
2061 }
2062 
2063 /*
2064  * Set up a routing table entry, normally
2065  * for an interface.
2066  */
2067 #define _SOCKADDR_TMPSIZE 128 /* Not too big.. kernel stack size is limited */
2068 static inline  int
2069 rtinit1(struct ifaddr *ifa, int cmd, int flags, int fibnum)
2070 {
2071 	RIB_RLOCK_TRACKER;
2072 	struct sockaddr *dst;
2073 	struct sockaddr *netmask;
2074 	struct rtentry *rt = NULL;
2075 	struct rt_addrinfo info;
2076 	int error = 0;
2077 	int startfib, endfib;
2078 	char tempbuf[_SOCKADDR_TMPSIZE];
2079 	int didwork = 0;
2080 	int a_failure = 0;
2081 	struct sockaddr_dl *sdl = NULL;
2082 	struct rib_head *rnh;
2083 
2084 	if (flags & RTF_HOST) {
2085 		dst = ifa->ifa_dstaddr;
2086 		netmask = NULL;
2087 	} else {
2088 		dst = ifa->ifa_addr;
2089 		netmask = ifa->ifa_netmask;
2090 	}
2091 	if (dst->sa_len == 0)
2092 		return(EINVAL);
2093 	switch (dst->sa_family) {
2094 	case AF_INET6:
2095 	case AF_INET:
2096 		/* We support multiple FIBs. */
2097 		break;
2098 	default:
2099 		fibnum = RT_DEFAULT_FIB;
2100 		break;
2101 	}
2102 	if (fibnum == RT_ALL_FIBS) {
2103 		if (V_rt_add_addr_allfibs == 0 && cmd == (int)RTM_ADD)
2104 			startfib = endfib = ifa->ifa_ifp->if_fib;
2105 		else {
2106 			startfib = 0;
2107 			endfib = rt_numfibs - 1;
2108 		}
2109 	} else {
2110 		KASSERT((fibnum < rt_numfibs), ("rtinit1: bad fibnum"));
2111 		startfib = fibnum;
2112 		endfib = fibnum;
2113 	}
2114 
2115 	/*
2116 	 * If it's a delete, check that if it exists,
2117 	 * it's on the correct interface or we might scrub
2118 	 * a route to another ifa which would
2119 	 * be confusing at best and possibly worse.
2120 	 */
2121 	if (cmd == RTM_DELETE) {
2122 		/*
2123 		 * It's a delete, so it should already exist..
2124 		 * If it's a net, mask off the host bits
2125 		 * (Assuming we have a mask)
2126 		 * XXX this is kinda inet specific..
2127 		 */
2128 		if (netmask != NULL) {
2129 			rt_maskedcopy(dst, (struct sockaddr *)tempbuf, netmask);
2130 			dst = (struct sockaddr *)tempbuf;
2131 		}
2132 	} else if (cmd == RTM_ADD) {
2133 		sdl = (struct sockaddr_dl *)tempbuf;
2134 		bzero(sdl, sizeof(struct sockaddr_dl));
2135 		sdl->sdl_family = AF_LINK;
2136 		sdl->sdl_len = sizeof(struct sockaddr_dl);
2137 		sdl->sdl_type = ifa->ifa_ifp->if_type;
2138 		sdl->sdl_index = ifa->ifa_ifp->if_index;
2139         }
2140 	/*
2141 	 * Now go through all the requested tables (fibs) and do the
2142 	 * requested action. Realistically, this will either be fib 0
2143 	 * for protocols that don't do multiple tables or all the
2144 	 * tables for those that do.
2145 	 */
2146 	for ( fibnum = startfib; fibnum <= endfib; fibnum++) {
2147 		if (cmd == RTM_DELETE) {
2148 			struct radix_node *rn;
2149 			/*
2150 			 * Look up an rtentry that is in the routing tree and
2151 			 * contains the correct info.
2152 			 */
2153 			rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
2154 			if (rnh == NULL)
2155 				/* this table doesn't exist but others might */
2156 				continue;
2157 			RIB_RLOCK(rnh);
2158 			rn = rnh->rnh_lookup(dst, netmask, &rnh->head);
2159 #ifdef RADIX_MPATH
2160 			if (rt_mpath_capable(rnh)) {
2161 
2162 				if (rn == NULL)
2163 					error = ESRCH;
2164 				else {
2165 					rt = RNTORT(rn);
2166 					/*
2167 					 * for interface route the
2168 					 * rt->rt_gateway is sockaddr_intf
2169 					 * for cloning ARP entries, so
2170 					 * rt_mpath_matchgate must use the
2171 					 * interface address
2172 					 */
2173 					rt = rt_mpath_matchgate(rt,
2174 					    ifa->ifa_addr);
2175 					if (rt == NULL)
2176 						error = ESRCH;
2177 				}
2178 			}
2179 #endif
2180 			error = (rn == NULL ||
2181 			    (rn->rn_flags & RNF_ROOT) ||
2182 			    RNTORT(rn)->rt_ifa != ifa);
2183 			RIB_RUNLOCK(rnh);
2184 			if (error) {
2185 				/* this is only an error if bad on ALL tables */
2186 				continue;
2187 			}
2188 		}
2189 		/*
2190 		 * Do the actual request
2191 		 */
2192 		bzero((caddr_t)&info, sizeof(info));
2193 		info.rti_ifa = ifa;
2194 		info.rti_flags = flags |
2195 		    (ifa->ifa_flags & ~IFA_RTSELF) | RTF_PINNED;
2196 		info.rti_info[RTAX_DST] = dst;
2197 		/*
2198 		 * doing this for compatibility reasons
2199 		 */
2200 		if (cmd == RTM_ADD)
2201 			info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)sdl;
2202 		else
2203 			info.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
2204 		info.rti_info[RTAX_NETMASK] = netmask;
2205 		error = rtrequest1_fib(cmd, &info, &rt, fibnum);
2206 		if (error == 0 && rt != NULL) {
2207 			/*
2208 			 * notify any listening routing agents of the change
2209 			 */
2210 			RT_LOCK(rt);
2211 #ifdef RADIX_MPATH
2212 			/*
2213 			 * in case address alias finds the first address
2214 			 * e.g. ifconfig bge0 192.0.2.246/24
2215 			 * e.g. ifconfig bge0 192.0.2.247/24
2216 			 * the address set in the route is 192.0.2.246
2217 			 * so we need to replace it with 192.0.2.247
2218 			 */
2219 			if (memcmp(rt->rt_ifa->ifa_addr,
2220 			    ifa->ifa_addr, ifa->ifa_addr->sa_len)) {
2221 				ifa_free(rt->rt_ifa);
2222 				ifa_ref(ifa);
2223 				rt->rt_ifp = ifa->ifa_ifp;
2224 				rt->rt_ifa = ifa;
2225 			}
2226 #endif
2227 			RT_ADDREF(rt);
2228 			RT_UNLOCK(rt);
2229 			rt_newaddrmsg_fib(cmd, ifa, rt, fibnum);
2230 			RT_LOCK(rt);
2231 			RT_REMREF(rt);
2232 			if (cmd == RTM_DELETE) {
2233 				/*
2234 				 * If we are deleting, and we found an entry,
2235 				 * then it's been removed from the tree..
2236 				 * now throw it away.
2237 				 */
2238 				RTFREE_LOCKED(rt);
2239 			} else {
2240 				if (cmd == RTM_ADD) {
2241 					/*
2242 					 * We just wanted to add it..
2243 					 * we don't actually need a reference.
2244 					 */
2245 					RT_REMREF(rt);
2246 				}
2247 				RT_UNLOCK(rt);
2248 			}
2249 			didwork = 1;
2250 		}
2251 		if (error)
2252 			a_failure = error;
2253 	}
2254 	if (cmd == RTM_DELETE) {
2255 		if (didwork) {
2256 			error = 0;
2257 		} else {
2258 			/* we only give an error if it wasn't in any table */
2259 			error = ((flags & RTF_HOST) ?
2260 			    EHOSTUNREACH : ENETUNREACH);
2261 		}
2262 	} else {
2263 		if (a_failure) {
2264 			/* return an error if any of them failed */
2265 			error = a_failure;
2266 		}
2267 	}
2268 	return (error);
2269 }
2270 
2271 /*
2272  * Set up a routing table entry, normally
2273  * for an interface.
2274  */
2275 int
2276 rtinit(struct ifaddr *ifa, int cmd, int flags)
2277 {
2278 	struct sockaddr *dst;
2279 	int fib = RT_DEFAULT_FIB;
2280 
2281 	if (flags & RTF_HOST) {
2282 		dst = ifa->ifa_dstaddr;
2283 	} else {
2284 		dst = ifa->ifa_addr;
2285 	}
2286 
2287 	switch (dst->sa_family) {
2288 	case AF_INET6:
2289 	case AF_INET:
2290 		/* We do support multiple FIBs. */
2291 		fib = RT_ALL_FIBS;
2292 		break;
2293 	}
2294 	return (rtinit1(ifa, cmd, flags, fib));
2295 }
2296 
2297 /*
2298  * Announce interface address arrival/withdraw
2299  * Returns 0 on success.
2300  */
2301 int
2302 rt_addrmsg(int cmd, struct ifaddr *ifa, int fibnum)
2303 {
2304 
2305 	KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE,
2306 	    ("unexpected cmd %d", cmd));
2307 	KASSERT(fibnum == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
2308 	    ("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
2309 
2310 	EVENTHANDLER_DIRECT_INVOKE(rt_addrmsg, ifa, cmd);
2311 	return (rtsock_addrmsg(cmd, ifa, fibnum));
2312 }
2313 
2314 /*
2315  * Announce kernel-originated route addition/removal to rtsock based on @rt data.
2316  * cmd: RTM_ cmd
2317  * @rt: valid rtentry
2318  * @ifp: target route interface
2319  * @fibnum: fib id or RT_ALL_FIBS
2320  *
2321  * Returns 0 on success.
2322  */
2323 int
2324 rt_routemsg(int cmd, struct rtentry *rt, struct ifnet *ifp, int rti_addrs,
2325     int fibnum)
2326 {
2327 
2328 	KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE,
2329 	    ("unexpected cmd %d", cmd));
2330 
2331 	KASSERT(fibnum == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
2332 	    ("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
2333 
2334 	KASSERT(rt_key(rt) != NULL, (":%s: rt_key must be supplied", __func__));
2335 
2336 	return (rtsock_routemsg(cmd, rt, ifp, 0, fibnum));
2337 }
2338 
2339 /*
2340  * Announce kernel-originated route addition/removal to rtsock based on @rt data.
2341  * cmd: RTM_ cmd
2342  * @info: addrinfo structure with valid data.
2343  * @fibnum: fib id or RT_ALL_FIBS
2344  *
2345  * Returns 0 on success.
2346  */
2347 int
2348 rt_routemsg_info(int cmd, struct rt_addrinfo *info, int fibnum)
2349 {
2350 
2351 	KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE || cmd == RTM_CHANGE,
2352 	    ("unexpected cmd %d", cmd));
2353 
2354 	KASSERT(fibnum == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
2355 	    ("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
2356 
2357 	KASSERT(info->rti_info[RTAX_DST] != NULL, (":%s: RTAX_DST must be supplied", __func__));
2358 
2359 	return (rtsock_routemsg_info(cmd, info, fibnum));
2360 }
2361 
2362 
2363 /*
2364  * This is called to generate messages from the routing socket
2365  * indicating a network interface has had addresses associated with it.
2366  */
2367 void
2368 rt_newaddrmsg_fib(int cmd, struct ifaddr *ifa, struct rtentry *rt, int fibnum)
2369 {
2370 
2371 	KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE,
2372 		("unexpected cmd %u", cmd));
2373 	KASSERT(fibnum == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
2374 	    ("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
2375 
2376 	if (cmd == RTM_ADD) {
2377 		rt_addrmsg(cmd, ifa, fibnum);
2378 		if (rt != NULL)
2379 			rt_routemsg(cmd, rt, ifa->ifa_ifp, 0, fibnum);
2380 	} else {
2381 		if (rt != NULL)
2382 			rt_routemsg(cmd, rt, ifa->ifa_ifp, 0, fibnum);
2383 		rt_addrmsg(cmd, ifa, fibnum);
2384 	}
2385 }
2386 
2387