xref: /dragonfly/sys/net/route.c (revision 3c7e5806)
1 /*
2  * Copyright (c) 2004, 2005 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Jeffrey M. Hsu.
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 DragonFly Project nor the names of its
16  *    contributors may be used to endorse or promote products derived
17  *    from this software without specific, prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
23  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
25  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
27  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
29  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1980, 1986, 1991, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  *
61  *	@(#)route.c	8.3 (Berkeley) 1/9/95
62  * $FreeBSD: src/sys/net/route.c,v 1.59.2.10 2003/01/17 08:04:00 ru Exp $
63  */
64 
65 #include "opt_inet.h"
66 #include "opt_mpls.h"
67 
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/malloc.h>
71 #include <sys/mbuf.h>
72 #include <sys/socket.h>
73 #include <sys/domain.h>
74 #include <sys/kernel.h>
75 #include <sys/sysctl.h>
76 #include <sys/globaldata.h>
77 #include <sys/thread.h>
78 
79 #include <net/if.h>
80 #include <net/if_var.h>
81 #include <net/route.h>
82 #include <net/netisr.h>
83 
84 #include <netinet/in.h>
85 #include <net/ip_mroute/ip_mroute.h>
86 
87 #include <sys/thread2.h>
88 #include <sys/msgport2.h>
89 #include <net/netmsg2.h>
90 #include <net/netisr2.h>
91 
92 #ifdef MPLS
93 #include <netproto/mpls/mpls.h>
94 #endif
95 
96 static struct rtstatistics rtstatistics_percpu[MAXCPU] __cachealign;
97 #define rtstat	rtstatistics_percpu[mycpuid]
98 
99 struct radix_node_head *rt_tables[MAXCPU][AF_MAX+1];
100 
101 static void	rt_maskedcopy (struct sockaddr *, struct sockaddr *,
102 			       struct sockaddr *);
103 static void rtable_init(void);
104 static void rtinit_rtrequest_callback(int, int, struct rt_addrinfo *,
105 				      struct rtentry *, void *);
106 
107 static void rtredirect_msghandler(netmsg_t msg);
108 static void rtrequest1_msghandler(netmsg_t msg);
109 static void rtsearch_msghandler(netmsg_t msg);
110 static void rtmask_add_msghandler(netmsg_t msg);
111 
112 static int rt_setshims(struct rtentry *, struct sockaddr **);
113 
114 SYSCTL_NODE(_net, OID_AUTO, route, CTLFLAG_RW, 0, "Routing");
115 
116 #ifdef ROUTE_DEBUG
117 static int route_debug = 1;
118 SYSCTL_INT(_net_route, OID_AUTO, route_debug, CTLFLAG_RW,
119 	   &route_debug, 0, "");
120 #endif
121 
122 u_long route_kmalloc_limit = 0;
123 TUNABLE_ULONG("net.route.kmalloc_limit", &route_kmalloc_limit);
124 
125 /*
126  * Initialize the route table(s) for protocol domains and
127  * create a helper thread which will be responsible for updating
128  * route table entries on each cpu.
129  */
130 void
131 route_init(void)
132 {
133 	int cpu;
134 
135 	if (route_kmalloc_limit)
136 		kmalloc_raise_limit(M_RTABLE, route_kmalloc_limit);
137 
138 	for (cpu = 0; cpu < netisr_ncpus; ++cpu)
139 		bzero(&rtstatistics_percpu[cpu], sizeof(struct rtstatistics));
140 	rn_init();      /* initialize all zeroes, all ones, mask table */
141 	rtable_init();	/* call dom_rtattach() on each cpu */
142 }
143 
144 static void
145 rtable_init_oncpu(netmsg_t msg)
146 {
147 	struct domain *dom;
148 	int cpu = mycpuid;
149 
150 	ASSERT_NETISR_NCPUS(cpu);
151 
152 	SLIST_FOREACH(dom, &domains, dom_next) {
153 		if (dom->dom_rtattach) {
154 			dom->dom_rtattach(
155 				(void **)&rt_tables[cpu][dom->dom_family],
156 				dom->dom_rtoffset);
157 		}
158 	}
159 	netisr_forwardmsg(&msg->base, cpu + 1);
160 }
161 
162 static void
163 rtable_init(void)
164 {
165 	struct netmsg_base msg;
166 
167 	netmsg_init(&msg, NULL, &curthread->td_msgport, 0, rtable_init_oncpu);
168 	netisr_domsg_global(&msg);
169 }
170 
171 /*
172  * Routing statistics.
173  */
174 static int
175 sysctl_rtstatistics(SYSCTL_HANDLER_ARGS)
176 {
177 	int cpu, error = 0;
178 
179 	for (cpu = 0; cpu < netisr_ncpus; ++cpu) {
180 		if ((error = SYSCTL_OUT(req, &rtstatistics_percpu[cpu],
181 					sizeof(struct rtstatistics))))
182 				break;
183 		if ((error = SYSCTL_IN(req, &rtstatistics_percpu[cpu],
184 					sizeof(struct rtstatistics))))
185 				break;
186 	}
187 
188 	return (error);
189 }
190 SYSCTL_PROC(_net_route, OID_AUTO, stats, (CTLTYPE_OPAQUE|CTLFLAG_RW),
191 	0, 0, sysctl_rtstatistics, "S,rtstatistics", "Routing statistics");
192 
193 /*
194  * Packet routing routines.
195  */
196 
197 /*
198  * Look up and fill in the "ro_rt" rtentry field in a route structure given
199  * an address in the "ro_dst" field.  Always send a report on a miss and
200  * always clone routes.
201  */
202 void
203 rtalloc(struct route *ro)
204 {
205 	rtalloc_ign(ro, 0UL);
206 }
207 
208 /*
209  * Look up and fill in the "ro_rt" rtentry field in a route structure given
210  * an address in the "ro_dst" field.  Always send a report on a miss and
211  * optionally clone routes when RTF_CLONING or RTF_PRCLONING are not being
212  * ignored.
213  */
214 void
215 rtalloc_ign(struct route *ro, u_long ignoreflags)
216 {
217 	if (ro->ro_rt != NULL) {
218 		if (ro->ro_rt->rt_ifp != NULL && ro->ro_rt->rt_flags & RTF_UP)
219 			return;
220 		rtfree(ro->ro_rt);
221 		ro->ro_rt = NULL;
222 	}
223 	ro->ro_rt = _rtlookup(&ro->ro_dst, RTL_REPORTMSG, ignoreflags);
224 }
225 
226 /*
227  * Look up the route that matches the given "dst" address.
228  *
229  * Route lookup can have the side-effect of creating and returning
230  * a cloned route instead when "dst" matches a cloning route and the
231  * RTF_CLONING and RTF_PRCLONING flags are not being ignored.
232  *
233  * Any route returned has its reference count incremented.
234  */
235 struct rtentry *
236 _rtlookup(struct sockaddr *dst, boolean_t generate_report, u_long ignore)
237 {
238 	struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
239 	struct rtentry *rt;
240 
241 	ASSERT_NETISR_NCPUS(mycpuid);
242 
243 	if (rnh == NULL)
244 		goto unreach;
245 
246 	/*
247 	 * Look up route in the radix tree.
248 	 */
249 	rt = (struct rtentry *) rnh->rnh_matchaddr((char *)dst, rnh);
250 	if (rt == NULL)
251 		goto unreach;
252 
253 	/*
254 	 * Handle cloning routes.
255 	 */
256 	if ((rt->rt_flags & ~ignore & (RTF_CLONING | RTF_PRCLONING)) != 0) {
257 		struct rtentry *clonedroute;
258 		int error;
259 
260 		clonedroute = rt;	/* copy in/copy out parameter */
261 		error = rtrequest(RTM_RESOLVE, dst, NULL, NULL, 0,
262 				  &clonedroute);	/* clone the route */
263 		if (error != 0) {	/* cloning failed */
264 			if (generate_report)
265 				rt_dstmsg(RTM_MISS, dst, error);
266 			rt->rt_refcnt++;
267 			return (rt);	/* return the uncloned route */
268 		}
269 		if (generate_report) {
270 			if (clonedroute->rt_flags & RTF_XRESOLVE)
271 				rt_dstmsg(RTM_RESOLVE, dst, 0);
272 			else
273 				rt_rtmsg(RTM_ADD, clonedroute,
274 					 clonedroute->rt_ifp, 0);
275 		}
276 		return (clonedroute);	/* return cloned route */
277 	}
278 
279 	/*
280 	 * Increment the reference count of the matched route and return.
281 	 */
282 	rt->rt_refcnt++;
283 	return (rt);
284 
285 unreach:
286 	rtstat.rts_unreach++;
287 	if (generate_report)
288 		rt_dstmsg(RTM_MISS, dst, 0);
289 	return (NULL);
290 }
291 
292 void
293 rtfree(struct rtentry *rt)
294 {
295 
296 	ASSERT_NETISR_NCPUS(rt->rt_cpuid);
297 	KASSERT(rt->rt_refcnt > 0, ("rtfree: rt_refcnt %ld", rt->rt_refcnt));
298 
299 	--rt->rt_refcnt;
300 	if (rt->rt_refcnt == 0) {
301 		struct radix_node_head *rnh =
302 		    rt_tables[mycpuid][rt_key(rt)->sa_family];
303 
304 		if (rnh->rnh_close)
305 			rnh->rnh_close((struct radix_node *)rt, rnh);
306 		if (!(rt->rt_flags & RTF_UP)) {
307 			/* deallocate route */
308 			if (rt->rt_ifa != NULL)
309 				IFAFREE(rt->rt_ifa);
310 			if (rt->rt_parent != NULL)
311 				RTFREE(rt->rt_parent);	/* recursive call! */
312 			Free(rt_key(rt));
313 			Free(rt);
314 		}
315 	}
316 }
317 
318 static void
319 rtfree_async_dispatch(netmsg_t msg)
320 {
321 	struct rtentry *rt = msg->lmsg.u.ms_resultp;
322 
323 	rtfree(rt);
324 	netisr_replymsg(&msg->base, 0);
325 }
326 
327 void
328 rtfree_async(struct rtentry *rt)
329 {
330 	struct netmsg_base *msg;
331 
332 	if (IN_NETISR_NCPUS(rt->rt_cpuid)) {
333 		rtfree(rt);
334 		return;
335 	}
336 
337 	KASSERT(rt->rt_refcnt > 0,
338 	    ("rtfree_async: rt_refcnt %ld", rt->rt_refcnt));
339 
340 	msg = kmalloc(sizeof(*msg), M_LWKTMSG, M_INTWAIT);
341 	netmsg_init(msg, NULL, &netisr_afree_rport, 0, rtfree_async_dispatch);
342 	msg->lmsg.u.ms_resultp = rt;
343 
344 	netisr_sendmsg(msg, rt->rt_cpuid);
345 }
346 
347 int
348 rtredirect_oncpu(struct sockaddr *dst, struct sockaddr *gateway,
349 		 struct sockaddr *netmask, int flags, struct sockaddr *src)
350 {
351 	struct rtentry *rt = NULL;
352 	struct rt_addrinfo rtinfo;
353 	struct ifaddr *ifa;
354 	u_long *stat = NULL;
355 	int error;
356 
357 	ASSERT_NETISR_NCPUS(mycpuid);
358 
359 	/* verify the gateway is directly reachable */
360 	if ((ifa = ifa_ifwithnet(gateway)) == NULL) {
361 		error = ENETUNREACH;
362 		goto out;
363 	}
364 
365 	/*
366 	 * If the redirect isn't from our current router for this destination,
367 	 * it's either old or wrong.
368 	 */
369 	if (!(flags & RTF_DONE) &&		/* XXX JH */
370 	    (rt = rtpurelookup(dst)) != NULL &&
371 	    (!sa_equal(src, rt->rt_gateway) || rt->rt_ifa != ifa)) {
372 		error = EINVAL;
373 		goto done;
374 	}
375 
376 	/*
377 	 * If it redirects us to ourselves, we have a routing loop,
378 	 * perhaps as a result of an interface going down recently.
379 	 */
380 	if (ifa_ifwithaddr(gateway)) {
381 		error = EHOSTUNREACH;
382 		goto done;
383 	}
384 
385 	/*
386 	 * Create a new entry if the lookup failed or if we got back
387 	 * a wildcard entry for the default route.  This is necessary
388 	 * for hosts which use routing redirects generated by smart
389 	 * gateways to dynamically build the routing tables.
390 	 */
391 	if (rt == NULL)
392 		goto create;
393 	if ((rt_mask(rt) != NULL && rt_mask(rt)->sa_len < 2)) {
394 		rtfree(rt);
395 		goto create;
396 	}
397 
398 	/* Ignore redirects for directly connected hosts. */
399 	if (!(rt->rt_flags & RTF_GATEWAY)) {
400 		error = EHOSTUNREACH;
401 		goto done;
402 	}
403 
404 	if (!(rt->rt_flags & RTF_HOST) && (flags & RTF_HOST)) {
405 		/*
406 		 * Changing from a network route to a host route.
407 		 * Create a new host route rather than smashing the
408 		 * network route.
409 		 */
410 create:
411 		flags |=  RTF_GATEWAY | RTF_DYNAMIC;
412 		bzero(&rtinfo, sizeof(struct rt_addrinfo));
413 		rtinfo.rti_info[RTAX_DST] = dst;
414 		rtinfo.rti_info[RTAX_GATEWAY] = gateway;
415 		rtinfo.rti_info[RTAX_NETMASK] = netmask;
416 		rtinfo.rti_flags = flags;
417 		rtinfo.rti_ifa = ifa;
418 		rt = NULL;	/* copy-in/copy-out parameter */
419 		error = rtrequest1(RTM_ADD, &rtinfo, &rt);
420 		if (rt != NULL)
421 			flags = rt->rt_flags;
422 		stat = &rtstat.rts_dynamic;
423 	} else {
424 		/*
425 		 * Smash the current notion of the gateway to this destination.
426 		 * Should check about netmask!!!
427 		 */
428 		rt->rt_flags |= RTF_MODIFIED;
429 		flags |= RTF_MODIFIED;
430 
431 		/* We only need to report rtmsg on CPU0 */
432 		rt_setgate(rt, rt_key(rt), gateway,
433 			   mycpuid == 0 ? RTL_REPORTMSG : RTL_DONTREPORT);
434 		error = 0;
435 		stat = &rtstat.rts_newgateway;
436 	}
437 
438 done:
439 	if (rt != NULL)
440 		rtfree(rt);
441 out:
442 	if (error != 0)
443 		rtstat.rts_badredirect++;
444 	else if (stat != NULL)
445 		(*stat)++;
446 
447 	return error;
448 }
449 
450 struct netmsg_rtredirect {
451 	struct netmsg_base base;
452 	struct sockaddr *dst;
453 	struct sockaddr *gateway;
454 	struct sockaddr *netmask;
455 	int		flags;
456 	struct sockaddr *src;
457 };
458 
459 /*
460  * Force a routing table entry to the specified
461  * destination to go through the given gateway.
462  * Normally called as a result of a routing redirect
463  * message from the network layer.
464  */
465 void
466 rtredirect(struct sockaddr *dst, struct sockaddr *gateway,
467 	   struct sockaddr *netmask, int flags, struct sockaddr *src)
468 {
469 	struct rt_addrinfo rtinfo;
470 	int error;
471 	struct netmsg_rtredirect msg;
472 
473 	netmsg_init(&msg.base, NULL, &curthread->td_msgport,
474 		    0, rtredirect_msghandler);
475 	msg.dst = dst;
476 	msg.gateway = gateway;
477 	msg.netmask = netmask;
478 	msg.flags = flags;
479 	msg.src = src;
480 	error = netisr_domsg_global(&msg.base);
481 
482 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
483 	rtinfo.rti_info[RTAX_DST] = dst;
484 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
485 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
486 	rtinfo.rti_info[RTAX_AUTHOR] = src;
487 	rt_missmsg(RTM_REDIRECT, &rtinfo, flags, error);
488 }
489 
490 static void
491 rtredirect_msghandler(netmsg_t msg)
492 {
493 	struct netmsg_rtredirect *rmsg = (void *)msg;
494 
495 	rtredirect_oncpu(rmsg->dst, rmsg->gateway, rmsg->netmask,
496 			 rmsg->flags, rmsg->src);
497 	netisr_forwardmsg(&msg->base, mycpuid + 1);
498 }
499 
500 /*
501 * Routing table ioctl interface.
502 */
503 int
504 rtioctl(u_long req, caddr_t data, struct ucred *cred)
505 {
506 #ifdef INET
507 	/* Multicast goop, grrr... */
508 	return mrt_ioctl ? mrt_ioctl(req, data) : EOPNOTSUPP;
509 #else
510 	return ENXIO;
511 #endif
512 }
513 
514 struct ifaddr *
515 ifa_ifwithroute(int flags, struct sockaddr *dst, struct sockaddr *gateway)
516 {
517 	struct ifaddr *ifa;
518 
519 	if (!(flags & RTF_GATEWAY)) {
520 		/*
521 		 * If we are adding a route to an interface,
522 		 * and the interface is a point-to-point link,
523 		 * we should search for the destination
524 		 * as our clue to the interface.  Otherwise
525 		 * we can use the local address.
526 		 */
527 		ifa = NULL;
528 		if (flags & RTF_HOST) {
529 			ifa = ifa_ifwithdstaddr(dst);
530 		}
531 		if (ifa == NULL)
532 			ifa = ifa_ifwithaddr(gateway);
533 	} else {
534 		/*
535 		 * If we are adding a route to a remote net
536 		 * or host, the gateway may still be on the
537 		 * other end of a pt to pt link.
538 		 */
539 		ifa = ifa_ifwithdstaddr(gateway);
540 	}
541 	if (ifa == NULL)
542 		ifa = ifa_ifwithnet(gateway);
543 	if (ifa == NULL) {
544 		struct rtentry *rt;
545 
546 		rt = rtpurelookup(gateway);
547 		if (rt == NULL)
548 			return (NULL);
549 		rt->rt_refcnt--;
550 		if ((ifa = rt->rt_ifa) == NULL)
551 			return (NULL);
552 	}
553 	if (ifa->ifa_addr->sa_family != dst->sa_family) {
554 		struct ifaddr *oldifa = ifa;
555 
556 		ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
557 		if (ifa == NULL)
558 			ifa = oldifa;
559 	}
560 	return (ifa);
561 }
562 
563 static int rt_fixdelete (struct radix_node *, void *);
564 static int rt_fixchange (struct radix_node *, void *);
565 
566 struct rtfc_arg {
567 	struct rtentry *rt0;
568 	struct radix_node_head *rnh;
569 };
570 
571 /*
572  * Set rtinfo->rti_ifa and rtinfo->rti_ifp.
573  */
574 int
575 rt_getifa(struct rt_addrinfo *rtinfo)
576 {
577 	struct sockaddr *gateway = rtinfo->rti_info[RTAX_GATEWAY];
578 	struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
579 	struct sockaddr *ifaaddr = rtinfo->rti_info[RTAX_IFA];
580 	int flags = rtinfo->rti_flags;
581 
582 	/*
583 	 * ifp may be specified by sockaddr_dl
584 	 * when protocol address is ambiguous.
585 	 */
586 	if (rtinfo->rti_ifp == NULL) {
587 		struct sockaddr *ifpaddr;
588 
589 		ifpaddr = rtinfo->rti_info[RTAX_IFP];
590 		if (ifpaddr != NULL && ifpaddr->sa_family == AF_LINK) {
591 			struct ifaddr *ifa;
592 
593 			ifa = ifa_ifwithnet(ifpaddr);
594 			if (ifa != NULL)
595 				rtinfo->rti_ifp = ifa->ifa_ifp;
596 		}
597 	}
598 
599 	if (rtinfo->rti_ifa == NULL && ifaaddr != NULL)
600 		rtinfo->rti_ifa = ifa_ifwithaddr(ifaaddr);
601 	if (rtinfo->rti_ifa == NULL) {
602 		struct sockaddr *sa;
603 
604 		sa = ifaaddr != NULL ? ifaaddr :
605 		    (gateway != NULL ? gateway : dst);
606 		if (sa != NULL && rtinfo->rti_ifp != NULL)
607 			rtinfo->rti_ifa = ifaof_ifpforaddr(sa, rtinfo->rti_ifp);
608 		else if (dst != NULL && gateway != NULL)
609 			rtinfo->rti_ifa = ifa_ifwithroute(flags, dst, gateway);
610 		else if (sa != NULL)
611 			rtinfo->rti_ifa = ifa_ifwithroute(flags, sa, sa);
612 	}
613 	if (rtinfo->rti_ifa == NULL)
614 		return (ENETUNREACH);
615 
616 	if (rtinfo->rti_ifp == NULL)
617 		rtinfo->rti_ifp = rtinfo->rti_ifa->ifa_ifp;
618 	return (0);
619 }
620 
621 /*
622  * Do appropriate manipulations of a routing tree given
623  * all the bits of info needed
624  */
625 int
626 rtrequest(
627 	int req,
628 	struct sockaddr *dst,
629 	struct sockaddr *gateway,
630 	struct sockaddr *netmask,
631 	int flags,
632 	struct rtentry **ret_nrt)
633 {
634 	struct rt_addrinfo rtinfo;
635 
636 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
637 	rtinfo.rti_info[RTAX_DST] = dst;
638 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
639 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
640 	rtinfo.rti_flags = flags;
641 	return rtrequest1(req, &rtinfo, ret_nrt);
642 }
643 
644 int
645 rtrequest_global(
646 	int req,
647 	struct sockaddr *dst,
648 	struct sockaddr *gateway,
649 	struct sockaddr *netmask,
650 	int flags)
651 {
652 	struct rt_addrinfo rtinfo;
653 
654 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
655 	rtinfo.rti_info[RTAX_DST] = dst;
656 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
657 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
658 	rtinfo.rti_flags = flags;
659 	return rtrequest1_global(req, &rtinfo, NULL, NULL, RTREQ_PRIO_NORM);
660 }
661 
662 struct netmsg_rtq {
663 	struct netmsg_base	base;
664 	int			req;
665 	struct rt_addrinfo	*rtinfo;
666 	rtrequest1_callback_func_t callback;
667 	void			*arg;
668 };
669 
670 int
671 rtrequest1_global(int req, struct rt_addrinfo *rtinfo,
672     rtrequest1_callback_func_t callback, void *arg, boolean_t req_prio)
673 {
674 	struct netmsg_rtq msg;
675 	int flags = 0;
676 
677 	if (req_prio)
678 		flags = MSGF_PRIORITY;
679 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
680 	    rtrequest1_msghandler);
681 	msg.base.lmsg.ms_error = -1;
682 	msg.req = req;
683 	msg.rtinfo = rtinfo;
684 	msg.callback = callback;
685 	msg.arg = arg;
686 	return (netisr_domsg_global(&msg.base));
687 }
688 
689 /*
690  * Handle a route table request on the current cpu.  Since the route table's
691  * are supposed to be identical on each cpu, an error occuring later in the
692  * message chain is considered system-fatal.
693  */
694 static void
695 rtrequest1_msghandler(netmsg_t msg)
696 {
697 	struct netmsg_rtq *rmsg = (void *)msg;
698 	struct rt_addrinfo rtinfo;
699 	struct rtentry *rt = NULL;
700 	int error;
701 
702 	/*
703 	 * Copy the rtinfo.  We need to make sure that the original
704 	 * rtinfo, which is setup by the caller, in the netmsg will
705 	 * _not_ be changed; else the next CPU on the netmsg forwarding
706 	 * path will see a different rtinfo than what this CPU has seen.
707 	 */
708 	rtinfo = *rmsg->rtinfo;
709 
710 	error = rtrequest1(rmsg->req, &rtinfo, &rt);
711 	if (rt)
712 		--rt->rt_refcnt;
713 	if (rmsg->callback)
714 		rmsg->callback(rmsg->req, error, &rtinfo, rt, rmsg->arg);
715 
716 	/*
717 	 * RTM_DELETE's are propogated even if an error occurs, since a
718 	 * cloned route might be undergoing deletion and cloned routes
719 	 * are not necessarily replicated.  An overall error is returned
720 	 * only if no cpus have the route in question.
721 	 */
722 	if (rmsg->base.lmsg.ms_error < 0 || error == 0)
723 		rmsg->base.lmsg.ms_error = error;
724 
725 	if (error && rmsg->req != RTM_DELETE) {
726 		if (mycpuid != 0) {
727 			panic("rtrequest1_msghandler: rtrequest table req %d, "
728 			    "failed on cpu%d, error %d\n",
729 			    rmsg->req, mycpuid, error);
730 		}
731 		netisr_replymsg(&rmsg->base, error);
732 	} else {
733 		netisr_forwardmsg_error(&rmsg->base, mycpuid + 1,
734 		    rmsg->base.lmsg.ms_error);
735 	}
736 }
737 
738 int
739 rtrequest1(int req, struct rt_addrinfo *rtinfo, struct rtentry **ret_nrt)
740 {
741 	struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
742 	struct rtentry *rt;
743 	struct radix_node *rn;
744 	struct radix_node_head *rnh;
745 	struct ifaddr *ifa;
746 	struct sockaddr *ndst;
747 	boolean_t reportmsg;
748 	int error = 0;
749 
750 	ASSERT_NETISR_NCPUS(mycpuid);
751 
752 #define gotoerr(x) { error = x ; goto bad; }
753 
754 #ifdef ROUTE_DEBUG
755 	if (route_debug)
756 		rt_addrinfo_print(req, rtinfo);
757 #endif
758 
759 	crit_enter();
760 	/*
761 	 * Find the correct routing tree to use for this Address Family
762 	 */
763 	if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL)
764 		gotoerr(EAFNOSUPPORT);
765 
766 	/*
767 	 * If we are adding a host route then we don't want to put
768 	 * a netmask in the tree, nor do we want to clone it.
769 	 */
770 	if (rtinfo->rti_flags & RTF_HOST) {
771 		rtinfo->rti_info[RTAX_NETMASK] = NULL;
772 		rtinfo->rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
773 	}
774 
775 	switch (req) {
776 	case RTM_DELETE:
777 		/* Remove the item from the tree. */
778 		rn = rnh->rnh_deladdr((char *)rtinfo->rti_info[RTAX_DST],
779 				      (char *)rtinfo->rti_info[RTAX_NETMASK],
780 				      rnh);
781 		if (rn == NULL)
782 			gotoerr(ESRCH);
783 		KASSERT(!(rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)),
784 			("rnh_deladdr returned flags 0x%x", rn->rn_flags));
785 		rt = (struct rtentry *)rn;
786 
787 		/* ref to prevent a deletion race */
788 		++rt->rt_refcnt;
789 
790 		/* Free any routes cloned from this one. */
791 		if ((rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) &&
792 		    rt_mask(rt) != NULL) {
793 			rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
794 					       (char *)rt_mask(rt),
795 					       rt_fixdelete, rt);
796 		}
797 
798 		if (rt->rt_gwroute != NULL) {
799 			RTFREE(rt->rt_gwroute);
800 			rt->rt_gwroute = NULL;
801 		}
802 
803 		/*
804 		 * NB: RTF_UP must be set during the search above,
805 		 * because we might delete the last ref, causing
806 		 * rt to get freed prematurely.
807 		 */
808 		rt->rt_flags &= ~RTF_UP;
809 
810 #ifdef ROUTE_DEBUG
811 		if (route_debug)
812 			rt_print(rtinfo, rt);
813 #endif
814 
815 		/* Give the protocol a chance to keep things in sync. */
816 		if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
817 			ifa->ifa_rtrequest(RTM_DELETE, rt);
818 
819 		/*
820 		 * If the caller wants it, then it can have it,
821 		 * but it's up to it to free the rtentry as we won't be
822 		 * doing it.
823 		 */
824 		KASSERT(rt->rt_refcnt >= 0,
825 			("rtrequest1(DELETE): refcnt %ld", rt->rt_refcnt));
826 		if (ret_nrt != NULL) {
827 			/* leave ref intact for return */
828 			*ret_nrt = rt;
829 		} else {
830 			/* deref / attempt to destroy */
831 			rtfree(rt);
832 		}
833 		break;
834 
835 	case RTM_RESOLVE:
836 		if (ret_nrt == NULL || (rt = *ret_nrt) == NULL)
837 			gotoerr(EINVAL);
838 
839 		KASSERT(rt->rt_cpuid == mycpuid,
840 		    ("rt resolve rt_cpuid %d, mycpuid %d",
841 		     rt->rt_cpuid, mycpuid));
842 
843 		ifa = rt->rt_ifa;
844 		rtinfo->rti_flags =
845 		    rt->rt_flags & ~(RTF_CLONING | RTF_PRCLONING | RTF_STATIC);
846 		rtinfo->rti_flags |= RTF_WASCLONED;
847 		rtinfo->rti_info[RTAX_GATEWAY] = rt->rt_gateway;
848 		if ((rtinfo->rti_info[RTAX_NETMASK] = rt->rt_genmask) == NULL)
849 			rtinfo->rti_flags |= RTF_HOST;
850 		rtinfo->rti_info[RTAX_MPLS1] = rt->rt_shim[0];
851 		rtinfo->rti_info[RTAX_MPLS2] = rt->rt_shim[1];
852 		rtinfo->rti_info[RTAX_MPLS3] = rt->rt_shim[2];
853 		goto makeroute;
854 
855 	case RTM_ADD:
856 		KASSERT(!(rtinfo->rti_flags & RTF_GATEWAY) ||
857 			rtinfo->rti_info[RTAX_GATEWAY] != NULL,
858 		    ("rtrequest: GATEWAY but no gateway"));
859 
860 		if (rtinfo->rti_ifa == NULL && (error = rt_getifa(rtinfo)))
861 			gotoerr(error);
862 		ifa = rtinfo->rti_ifa;
863 makeroute:
864 		R_Malloc(rt, struct rtentry *, sizeof(struct rtentry));
865 		if (rt == NULL) {
866 			if (req == RTM_ADD) {
867 				kprintf("rtrequest1: alloc rtentry failed on "
868 				    "cpu%d\n", mycpuid);
869 			}
870 			gotoerr(ENOBUFS);
871 		}
872 		bzero(rt, sizeof(struct rtentry));
873 		rt->rt_flags = RTF_UP | rtinfo->rti_flags;
874 		rt->rt_cpuid = mycpuid;
875 
876 		if (mycpuid != 0 && req == RTM_ADD) {
877 			/* For RTM_ADD, we have already sent rtmsg on CPU0. */
878 			reportmsg = RTL_DONTREPORT;
879 		} else {
880 			/*
881 			 * For RTM_ADD, we only send rtmsg on CPU0.
882 			 * For RTM_RESOLVE, we always send rtmsg. XXX
883 			 */
884 			reportmsg = RTL_REPORTMSG;
885 		}
886 		error = rt_setgate(rt, dst, rtinfo->rti_info[RTAX_GATEWAY],
887 				   reportmsg);
888 		if (error != 0) {
889 			Free(rt);
890 			gotoerr(error);
891 		}
892 
893 		ndst = rt_key(rt);
894 		if (rtinfo->rti_info[RTAX_NETMASK] != NULL)
895 			rt_maskedcopy(dst, ndst,
896 				      rtinfo->rti_info[RTAX_NETMASK]);
897 		else
898 			bcopy(dst, ndst, dst->sa_len);
899 
900 		if (rtinfo->rti_info[RTAX_MPLS1] != NULL)
901 			rt_setshims(rt, rtinfo->rti_info);
902 
903 		/*
904 		 * Note that we now have a reference to the ifa.
905 		 * This moved from below so that rnh->rnh_addaddr() can
906 		 * examine the ifa and  ifa->ifa_ifp if it so desires.
907 		 */
908 		IFAREF(ifa);
909 		rt->rt_ifa = ifa;
910 		rt->rt_ifp = ifa->ifa_ifp;
911 		/* XXX mtu manipulation will be done in rnh_addaddr -- itojun */
912 
913 		rn = rnh->rnh_addaddr((char *)ndst,
914 				      (char *)rtinfo->rti_info[RTAX_NETMASK],
915 				      rnh, rt->rt_nodes);
916 		if (rn == NULL) {
917 			struct rtentry *oldrt;
918 
919 			/*
920 			 * We already have one of these in the tree.
921 			 * We do a special hack: if the old route was
922 			 * cloned, then we blow it away and try
923 			 * re-inserting the new one.
924 			 */
925 			oldrt = rtpurelookup(ndst);
926 			if (oldrt != NULL) {
927 				--oldrt->rt_refcnt;
928 				if (oldrt->rt_flags & RTF_WASCLONED) {
929 					rtrequest(RTM_DELETE, rt_key(oldrt),
930 						  oldrt->rt_gateway,
931 						  rt_mask(oldrt),
932 						  oldrt->rt_flags, NULL);
933 					rn = rnh->rnh_addaddr((char *)ndst,
934 					    (char *)
935 						rtinfo->rti_info[RTAX_NETMASK],
936 					    rnh, rt->rt_nodes);
937 				}
938 			}
939 		}
940 		/* NOTE: rt_ifa may have been changed */
941 		ifa = rt->rt_ifa;
942 
943 		/*
944 		 * If it still failed to go into the tree,
945 		 * then un-make it (this should be a function).
946 		 */
947 		if (rn == NULL) {
948 			if (rt->rt_gwroute != NULL)
949 				rtfree(rt->rt_gwroute);
950 			IFAFREE(ifa);
951 			Free(rt_key(rt));
952 			Free(rt);
953 			gotoerr(EEXIST);
954 		}
955 
956 		/*
957 		 * If we got here from RESOLVE, then we are cloning
958 		 * so clone the rest, and note that we
959 		 * are a clone (and increment the parent's references)
960 		 */
961 		if (req == RTM_RESOLVE) {
962 			rt->rt_rmx = (*ret_nrt)->rt_rmx;    /* copy metrics */
963 			rt->rt_rmx.rmx_pksent = 0;  /* reset packet counter */
964 			if ((*ret_nrt)->rt_flags &
965 				       (RTF_CLONING | RTF_PRCLONING)) {
966 				rt->rt_parent = *ret_nrt;
967 				(*ret_nrt)->rt_refcnt++;
968 			}
969 		}
970 
971 		/*
972 		 * if this protocol has something to add to this then
973 		 * allow it to do that as well.
974 		 */
975 		if (ifa->ifa_rtrequest != NULL)
976 			ifa->ifa_rtrequest(req, rt);
977 
978 		/*
979 		 * We repeat the same procedure from rt_setgate() here because
980 		 * it doesn't fire when we call it there because the node
981 		 * hasn't been added to the tree yet.
982 		 */
983 		if (req == RTM_ADD && !(rt->rt_flags & RTF_HOST) &&
984 		    rt_mask(rt) != NULL) {
985 			struct rtfc_arg arg = { rt, rnh };
986 
987 			rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
988 					       (char *)rt_mask(rt),
989 					       rt_fixchange, &arg);
990 		}
991 
992 #ifdef ROUTE_DEBUG
993 		if (route_debug)
994 			rt_print(rtinfo, rt);
995 #endif
996 		/*
997 		 * Return the resulting rtentry,
998 		 * increasing the number of references by one.
999 		 */
1000 		if (ret_nrt != NULL) {
1001 			rt->rt_refcnt++;
1002 			*ret_nrt = rt;
1003 		}
1004 		break;
1005 	default:
1006 		error = EOPNOTSUPP;
1007 	}
1008 bad:
1009 #ifdef ROUTE_DEBUG
1010 	if (route_debug) {
1011 		if (error)
1012 			kprintf("rti %p failed error %d\n", rtinfo, error);
1013 		else
1014 			kprintf("rti %p succeeded\n", rtinfo);
1015 	}
1016 #endif
1017 	crit_exit();
1018 	return (error);
1019 }
1020 
1021 /*
1022  * Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family''
1023  * (i.e., the routes related to it by the operation of cloning).  This
1024  * routine is iterated over all potential former-child-routes by way of
1025  * rnh->rnh_walktree_from() above, and those that actually are children of
1026  * the late parent (passed in as VP here) are themselves deleted.
1027  */
1028 static int
1029 rt_fixdelete(struct radix_node *rn, void *vp)
1030 {
1031 	struct rtentry *rt = (struct rtentry *)rn;
1032 	struct rtentry *rt0 = vp;
1033 
1034 	if (rt->rt_parent == rt0 &&
1035 	    !(rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1036 		return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1037 				 rt->rt_flags, NULL);
1038 	}
1039 	return 0;
1040 }
1041 
1042 /*
1043  * This routine is called from rt_setgate() to do the analogous thing for
1044  * adds and changes.  There is the added complication in this case of a
1045  * middle insert; i.e., insertion of a new network route between an older
1046  * network route and (cloned) host routes.  For this reason, a simple check
1047  * of rt->rt_parent is insufficient; each candidate route must be tested
1048  * against the (mask, value) of the new route (passed as before in vp)
1049  * to see if the new route matches it.
1050  *
1051  * XXX - it may be possible to do fixdelete() for changes and reserve this
1052  * routine just for adds.  I'm not sure why I thought it was necessary to do
1053  * changes this way.
1054  */
1055 #ifdef DEBUG
1056 static int rtfcdebug = 0;
1057 #endif
1058 
1059 static int
1060 rt_fixchange(struct radix_node *rn, void *vp)
1061 {
1062 	struct rtentry *rt = (struct rtentry *)rn;
1063 	struct rtfc_arg *ap = vp;
1064 	struct rtentry *rt0 = ap->rt0;
1065 	struct radix_node_head *rnh = ap->rnh;
1066 	u_char *xk1, *xm1, *xk2, *xmp;
1067 	int i, len, mlen;
1068 
1069 #ifdef DEBUG
1070 	if (rtfcdebug)
1071 		kprintf("rt_fixchange: rt %p, rt0 %p\n", rt, rt0);
1072 #endif
1073 
1074 	if (rt->rt_parent == NULL ||
1075 	    (rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1076 #ifdef DEBUG
1077 		if (rtfcdebug) kprintf("no parent, pinned or cloning\n");
1078 #endif
1079 		return 0;
1080 	}
1081 
1082 	if (rt->rt_parent == rt0) {
1083 #ifdef DEBUG
1084 		if (rtfcdebug) kprintf("parent match\n");
1085 #endif
1086 		return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1087 				 rt->rt_flags, NULL);
1088 	}
1089 
1090 	/*
1091 	 * There probably is a function somewhere which does this...
1092 	 * if not, there should be.
1093 	 */
1094 	len = imin(rt_key(rt0)->sa_len, rt_key(rt)->sa_len);
1095 
1096 	xk1 = (u_char *)rt_key(rt0);
1097 	xm1 = (u_char *)rt_mask(rt0);
1098 	xk2 = (u_char *)rt_key(rt);
1099 
1100 	/* avoid applying a less specific route */
1101 	xmp = (u_char *)rt_mask(rt->rt_parent);
1102 	mlen = rt_key(rt->rt_parent)->sa_len;
1103 	if (mlen > rt_key(rt0)->sa_len) {
1104 #ifdef DEBUG
1105 		if (rtfcdebug)
1106 			kprintf("rt_fixchange: inserting a less "
1107 			       "specific route\n");
1108 #endif
1109 		return 0;
1110 	}
1111 	for (i = rnh->rnh_treetop->rn_offset; i < mlen; i++) {
1112 		if ((xmp[i] & ~(xmp[i] ^ xm1[i])) != xmp[i]) {
1113 #ifdef DEBUG
1114 			if (rtfcdebug)
1115 				kprintf("rt_fixchange: inserting a less "
1116 				       "specific route\n");
1117 #endif
1118 			return 0;
1119 		}
1120 	}
1121 
1122 	for (i = rnh->rnh_treetop->rn_offset; i < len; i++) {
1123 		if ((xk2[i] & xm1[i]) != xk1[i]) {
1124 #ifdef DEBUG
1125 			if (rtfcdebug) kprintf("no match\n");
1126 #endif
1127 			return 0;
1128 		}
1129 	}
1130 
1131 	/*
1132 	 * OK, this node is a clone, and matches the node currently being
1133 	 * changed/added under the node's mask.  So, get rid of it.
1134 	 */
1135 #ifdef DEBUG
1136 	if (rtfcdebug) kprintf("deleting\n");
1137 #endif
1138 	return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1139 			 rt->rt_flags, NULL);
1140 }
1141 
1142 int
1143 rt_setgate(struct rtentry *rt0, struct sockaddr *dst, struct sockaddr *gate,
1144 	   boolean_t generate_report)
1145 {
1146 	char *space, *oldspace;
1147 	int dlen = RT_ROUNDUP(dst->sa_len), glen = RT_ROUNDUP(gate->sa_len);
1148 	struct rtentry *rt = rt0;
1149 	struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
1150 
1151 	ASSERT_NETISR_NCPUS(mycpuid);
1152 
1153 	/*
1154 	 * A host route with the destination equal to the gateway
1155 	 * will interfere with keeping LLINFO in the routing
1156 	 * table, so disallow it.
1157 	 */
1158 	if (((rt0->rt_flags & (RTF_HOST | RTF_GATEWAY | RTF_LLINFO)) ==
1159 			      (RTF_HOST | RTF_GATEWAY)) &&
1160 	    dst->sa_len == gate->sa_len &&
1161 	    sa_equal(dst, gate)) {
1162 		/*
1163 		 * The route might already exist if this is an RTM_CHANGE
1164 		 * or a routing redirect, so try to delete it.
1165 		 */
1166 		if (rt_key(rt0) != NULL)
1167 			rtrequest(RTM_DELETE, rt_key(rt0), rt0->rt_gateway,
1168 				  rt_mask(rt0), rt0->rt_flags, NULL);
1169 		return EADDRNOTAVAIL;
1170 	}
1171 
1172 	/*
1173 	 * Both dst and gateway are stored in the same malloc'ed chunk
1174 	 * (If I ever get my hands on....)
1175 	 * if we need to malloc a new chunk, then keep the old one around
1176 	 * till we don't need it any more.
1177 	 */
1178 	if (rt->rt_gateway == NULL ||
1179 	    glen > RT_ROUNDUP(rt->rt_gateway->sa_len)) {
1180 		oldspace = (char *)rt_key(rt);
1181 		R_Malloc(space, char *, dlen + glen);
1182 		if (space == NULL)
1183 			return ENOBUFS;
1184 		rt->rt_nodes->rn_key = space;
1185 	} else {
1186 		space = (char *)rt_key(rt);	/* Just use the old space. */
1187 		oldspace = NULL;
1188 	}
1189 
1190 	/* Set the gateway value. */
1191 	rt->rt_gateway = (struct sockaddr *)(space + dlen);
1192 	bcopy(gate, rt->rt_gateway, glen);
1193 
1194 	if (oldspace != NULL) {
1195 		/*
1196 		 * If we allocated a new chunk, preserve the original dst.
1197 		 * This way, rt_setgate() really just sets the gate
1198 		 * and leaves the dst field alone.
1199 		 */
1200 		bcopy(dst, space, dlen);
1201 		Free(oldspace);
1202 	}
1203 
1204 	/*
1205 	 * If there is already a gwroute, it's now almost definitely wrong
1206 	 * so drop it.
1207 	 */
1208 	if (rt->rt_gwroute != NULL) {
1209 		RTFREE(rt->rt_gwroute);
1210 		rt->rt_gwroute = NULL;
1211 	}
1212 	if (rt->rt_flags & RTF_GATEWAY) {
1213 		/*
1214 		 * Cloning loop avoidance: In the presence of
1215 		 * protocol-cloning and bad configuration, it is
1216 		 * possible to get stuck in bottomless mutual recursion
1217 		 * (rtrequest rt_setgate rtlookup).  We avoid this
1218 		 * by not allowing protocol-cloning to operate for
1219 		 * gateways (which is probably the correct choice
1220 		 * anyway), and avoid the resulting reference loops
1221 		 * by disallowing any route to run through itself as
1222 		 * a gateway.  This is obviously mandatory when we
1223 		 * get rt->rt_output().
1224 		 *
1225 		 * This breaks TTCP for hosts outside the gateway!  XXX JH
1226 		 */
1227 		rt->rt_gwroute = _rtlookup(gate, generate_report,
1228 					   RTF_PRCLONING);
1229 		if (rt->rt_gwroute == rt) {
1230 			rt->rt_gwroute = NULL;
1231 			--rt->rt_refcnt;
1232 			return EDQUOT; /* failure */
1233 		}
1234 	}
1235 
1236 	/*
1237 	 * This isn't going to do anything useful for host routes, so
1238 	 * don't bother.  Also make sure we have a reasonable mask
1239 	 * (we don't yet have one during adds).
1240 	 */
1241 	if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != NULL) {
1242 		struct rtfc_arg arg = { rt, rnh };
1243 
1244 		rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
1245 				       (char *)rt_mask(rt),
1246 				       rt_fixchange, &arg);
1247 	}
1248 
1249 	return 0;
1250 }
1251 
1252 static void
1253 rt_maskedcopy(
1254 	struct sockaddr *src,
1255 	struct sockaddr *dst,
1256 	struct sockaddr *netmask)
1257 {
1258 	u_char *cp1 = (u_char *)src;
1259 	u_char *cp2 = (u_char *)dst;
1260 	u_char *cp3 = (u_char *)netmask;
1261 	u_char *cplim = cp2 + *cp3;
1262 	u_char *cplim2 = cp2 + *cp1;
1263 
1264 	*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
1265 	cp3 += 2;
1266 	if (cplim > cplim2)
1267 		cplim = cplim2;
1268 	while (cp2 < cplim)
1269 		*cp2++ = *cp1++ & *cp3++;
1270 	if (cp2 < cplim2)
1271 		bzero(cp2, cplim2 - cp2);
1272 }
1273 
1274 int
1275 rt_llroute(struct sockaddr *dst, struct rtentry *rt0, struct rtentry **drt)
1276 {
1277 	struct rtentry *up_rt, *rt;
1278 
1279 	ASSERT_NETISR_NCPUS(mycpuid);
1280 
1281 	if (!(rt0->rt_flags & RTF_UP)) {
1282 		up_rt = rtlookup(dst);
1283 		if (up_rt == NULL)
1284 			return (EHOSTUNREACH);
1285 		up_rt->rt_refcnt--;
1286 	} else
1287 		up_rt = rt0;
1288 	if (up_rt->rt_flags & RTF_GATEWAY) {
1289 		if (up_rt->rt_gwroute == NULL) {
1290 			up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1291 			if (up_rt->rt_gwroute == NULL)
1292 				return (EHOSTUNREACH);
1293 		} else if (!(up_rt->rt_gwroute->rt_flags & RTF_UP)) {
1294 			rtfree(up_rt->rt_gwroute);
1295 			up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1296 			if (up_rt->rt_gwroute == NULL)
1297 				return (EHOSTUNREACH);
1298 		}
1299 		rt = up_rt->rt_gwroute;
1300 	} else
1301 		rt = up_rt;
1302 	if (rt->rt_flags & RTF_REJECT &&
1303 	    (rt->rt_rmx.rmx_expire == 0 ||		/* rt doesn't expire */
1304 	     time_uptime < rt->rt_rmx.rmx_expire))	/* rt not expired */
1305 		return (rt->rt_flags & RTF_HOST ?  EHOSTDOWN : EHOSTUNREACH);
1306 	*drt = rt;
1307 	return 0;
1308 }
1309 
1310 static int
1311 rt_setshims(struct rtentry *rt, struct sockaddr **rt_shim){
1312 	int i;
1313 
1314 	for (i=0; i<3; i++) {
1315 		struct sockaddr *shim = rt_shim[RTAX_MPLS1 + i];
1316 		int shimlen;
1317 
1318 		if (shim == NULL)
1319 			break;
1320 
1321 		shimlen = RT_ROUNDUP(shim->sa_len);
1322 		R_Malloc(rt->rt_shim[i], struct sockaddr *, shimlen);
1323 		bcopy(shim, rt->rt_shim[i], shimlen);
1324 	}
1325 
1326 	return 0;
1327 }
1328 
1329 #ifdef ROUTE_DEBUG
1330 
1331 /*
1332  * Print out a route table entry
1333  */
1334 void
1335 rt_print(struct rt_addrinfo *rtinfo, struct rtentry *rn)
1336 {
1337 	kprintf("rti %p cpu %d route %p flags %08lx: ",
1338 		rtinfo, mycpuid, rn, rn->rt_flags);
1339 	sockaddr_print(rt_key(rn));
1340 	kprintf(" mask ");
1341 	sockaddr_print(rt_mask(rn));
1342 	kprintf(" gw ");
1343 	sockaddr_print(rn->rt_gateway);
1344 	kprintf(" ifc \"%s\"", rn->rt_ifp ? rn->rt_ifp->if_dname : "?");
1345 	kprintf(" ifa %p\n", rn->rt_ifa);
1346 }
1347 
1348 void
1349 rt_addrinfo_print(int cmd, struct rt_addrinfo *rti)
1350 {
1351 	int didit = 0;
1352 	int i;
1353 
1354 #ifdef ROUTE_DEBUG
1355 	if (cmd == RTM_DELETE && route_debug > 1)
1356 		print_backtrace(-1);
1357 #endif
1358 
1359 	switch(cmd) {
1360 	case RTM_ADD:
1361 		kprintf("ADD ");
1362 		break;
1363 	case RTM_RESOLVE:
1364 		kprintf("RES ");
1365 		break;
1366 	case RTM_DELETE:
1367 		kprintf("DEL ");
1368 		break;
1369 	default:
1370 		kprintf("C%02d ", cmd);
1371 		break;
1372 	}
1373 	kprintf("rti %p cpu %d ", rti, mycpuid);
1374 	for (i = 0; i < rti->rti_addrs; ++i) {
1375 		if (rti->rti_info[i] == NULL)
1376 			continue;
1377 		if (didit)
1378 			kprintf(" ,");
1379 		switch(i) {
1380 		case RTAX_DST:
1381 			kprintf("(DST ");
1382 			break;
1383 		case RTAX_GATEWAY:
1384 			kprintf("(GWY ");
1385 			break;
1386 		case RTAX_NETMASK:
1387 			kprintf("(MSK ");
1388 			break;
1389 		case RTAX_GENMASK:
1390 			kprintf("(GEN ");
1391 			break;
1392 		case RTAX_IFP:
1393 			kprintf("(IFP ");
1394 			break;
1395 		case RTAX_IFA:
1396 			kprintf("(IFA ");
1397 			break;
1398 		case RTAX_AUTHOR:
1399 			kprintf("(AUT ");
1400 			break;
1401 		case RTAX_BRD:
1402 			kprintf("(BRD ");
1403 			break;
1404 		default:
1405 			kprintf("(?%02d ", i);
1406 			break;
1407 		}
1408 		sockaddr_print(rti->rti_info[i]);
1409 		kprintf(")");
1410 		didit = 1;
1411 	}
1412 	kprintf("\n");
1413 }
1414 
1415 void
1416 sockaddr_print(struct sockaddr *sa)
1417 {
1418 	struct sockaddr_in *sa4;
1419 	struct sockaddr_in6 *sa6;
1420 	int len;
1421 	int i;
1422 
1423 	if (sa == NULL) {
1424 		kprintf("NULL");
1425 		return;
1426 	}
1427 
1428 	len = sa->sa_len - offsetof(struct sockaddr, sa_data[0]);
1429 
1430 	switch(sa->sa_family) {
1431 	case AF_INET:
1432 	case AF_INET6:
1433 	default:
1434 		switch(sa->sa_family) {
1435 		case AF_INET:
1436 			sa4 = (struct sockaddr_in *)sa;
1437 			kprintf("INET %d %d.%d.%d.%d",
1438 				ntohs(sa4->sin_port),
1439 				(ntohl(sa4->sin_addr.s_addr) >> 24) & 255,
1440 				(ntohl(sa4->sin_addr.s_addr) >> 16) & 255,
1441 				(ntohl(sa4->sin_addr.s_addr) >> 8) & 255,
1442 				(ntohl(sa4->sin_addr.s_addr) >> 0) & 255
1443 			);
1444 			break;
1445 		case AF_INET6:
1446 			sa6 = (struct sockaddr_in6 *)sa;
1447 			kprintf("INET6 %d %04x:%04x%04x:%04x:%04x:%04x:%04x:%04x",
1448 				ntohs(sa6->sin6_port),
1449 				sa6->sin6_addr.s6_addr16[0],
1450 				sa6->sin6_addr.s6_addr16[1],
1451 				sa6->sin6_addr.s6_addr16[2],
1452 				sa6->sin6_addr.s6_addr16[3],
1453 				sa6->sin6_addr.s6_addr16[4],
1454 				sa6->sin6_addr.s6_addr16[5],
1455 				sa6->sin6_addr.s6_addr16[6],
1456 				sa6->sin6_addr.s6_addr16[7]
1457 			);
1458 			break;
1459 		default:
1460 			kprintf("AF%d ", sa->sa_family);
1461 			while (len > 0 && sa->sa_data[len-1] == 0)
1462 				--len;
1463 
1464 			for (i = 0; i < len; ++i) {
1465 				if (i)
1466 					kprintf(".");
1467 				kprintf("%d", (unsigned char)sa->sa_data[i]);
1468 			}
1469 			break;
1470 		}
1471 	}
1472 }
1473 
1474 #endif
1475 
1476 /*
1477  * Set up a routing table entry, normally for an interface.
1478  */
1479 int
1480 rtinit(struct ifaddr *ifa, int cmd, int flags)
1481 {
1482 	struct sockaddr *dst, *deldst, *netmask;
1483 	struct mbuf *m = NULL;
1484 	struct radix_node_head *rnh;
1485 	struct radix_node *rn;
1486 	struct rt_addrinfo rtinfo;
1487 	int error;
1488 
1489 	ASSERT_NETISR0;
1490 
1491 	if (flags & RTF_HOST) {
1492 		dst = ifa->ifa_dstaddr;
1493 		netmask = NULL;
1494 	} else {
1495 		dst = ifa->ifa_addr;
1496 		netmask = ifa->ifa_netmask;
1497 	}
1498 	/*
1499 	 * If it's a delete, check that if it exists, it's on the correct
1500 	 * interface or we might scrub a route to another ifa which would
1501 	 * be confusing at best and possibly worse.
1502 	 */
1503 	if (cmd == RTM_DELETE) {
1504 		/*
1505 		 * It's a delete, so it should already exist..
1506 		 * If it's a net, mask off the host bits
1507 		 * (Assuming we have a mask)
1508 		 */
1509 		if (netmask != NULL) {
1510 			m = m_get(M_NOWAIT, MT_SONAME);
1511 			if (m == NULL)
1512 				return (ENOBUFS);
1513 			mbuftrackid(m, 34);
1514 			deldst = mtod(m, struct sockaddr *);
1515 			rt_maskedcopy(dst, deldst, netmask);
1516 			dst = deldst;
1517 		}
1518 		/*
1519 		 * Look up an rtentry that is in the routing tree and
1520 		 * contains the correct info.
1521 		 */
1522 		if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL ||
1523 		    (rn = rnh->rnh_lookup((char *)dst,
1524 					  (char *)netmask, rnh)) == NULL ||
1525 		    ((struct rtentry *)rn)->rt_ifa != ifa ||
1526 		    !sa_equal((struct sockaddr *)rn->rn_key, dst)) {
1527 			if (m != NULL)
1528 				m_free(m);
1529 			return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1530 		}
1531 		/* XXX */
1532 #if 0
1533 		else {
1534 			/*
1535 			 * One would think that as we are deleting, and we know
1536 			 * it doesn't exist, we could just return at this point
1537 			 * with an "ELSE" clause, but apparently not..
1538 			 */
1539 			return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1540 		}
1541 #endif
1542 	}
1543 	/*
1544 	 * Do the actual request
1545 	 */
1546 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
1547 	rtinfo.rti_info[RTAX_DST] = dst;
1548 	rtinfo.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
1549 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
1550 	rtinfo.rti_flags = flags | ifa->ifa_flags;
1551 	rtinfo.rti_ifa = ifa;
1552 	error = rtrequest1_global(cmd, &rtinfo, rtinit_rtrequest_callback, ifa,
1553 	    RTREQ_PRIO_HIGH);
1554 	if (m != NULL)
1555 		m_free(m);
1556 	return (error);
1557 }
1558 
1559 static void
1560 rtinit_rtrequest_callback(int cmd, int error,
1561 			  struct rt_addrinfo *rtinfo, struct rtentry *rt,
1562 			  void *arg)
1563 {
1564 	struct ifaddr *ifa = arg;
1565 
1566 	if (error == 0 && rt) {
1567 		if (mycpuid == 0) {
1568 			++rt->rt_refcnt;
1569 			rt_newaddrmsg(cmd, ifa, error, rt);
1570 			--rt->rt_refcnt;
1571 		}
1572 		if (cmd == RTM_DELETE) {
1573 			if (rt->rt_refcnt == 0) {
1574 				++rt->rt_refcnt;
1575 				rtfree(rt);
1576 			}
1577 		}
1578 	}
1579 }
1580 
1581 struct netmsg_rts {
1582 	struct netmsg_base	base;
1583 	int			req;
1584 	struct rt_addrinfo	*rtinfo;
1585 	rtsearch_callback_func_t callback;
1586 	void			*arg;
1587 	boolean_t		exact_match;
1588 	int			found_cnt;
1589 };
1590 
1591 int
1592 rtsearch_global(int req, struct rt_addrinfo *rtinfo,
1593     rtsearch_callback_func_t callback, void *arg, boolean_t exact_match,
1594     boolean_t req_prio)
1595 {
1596 	struct netmsg_rts msg;
1597 	int flags = 0;
1598 
1599 	if (req_prio)
1600 		flags = MSGF_PRIORITY;
1601 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
1602 	    rtsearch_msghandler);
1603 	msg.req = req;
1604 	msg.rtinfo = rtinfo;
1605 	msg.callback = callback;
1606 	msg.arg = arg;
1607 	msg.exact_match = exact_match;
1608 	msg.found_cnt = 0;
1609 	return (netisr_domsg_global(&msg.base));
1610 }
1611 
1612 static void
1613 rtsearch_msghandler(netmsg_t msg)
1614 {
1615 	struct netmsg_rts *rmsg = (void *)msg;
1616 	struct rt_addrinfo rtinfo;
1617 	struct radix_node_head *rnh;
1618 	struct rtentry *rt;
1619 	int error;
1620 
1621 	ASSERT_NETISR_NCPUS(mycpuid);
1622 
1623 	/*
1624 	 * Copy the rtinfo.  We need to make sure that the original
1625 	 * rtinfo, which is setup by the caller, in the netmsg will
1626 	 * _not_ be changed; else the next CPU on the netmsg forwarding
1627 	 * path will see a different rtinfo than what this CPU has seen.
1628 	 */
1629 	rtinfo = *rmsg->rtinfo;
1630 
1631 	/*
1632 	 * Find the correct routing tree to use for this Address Family
1633 	 */
1634 	if ((rnh = rt_tables[mycpuid][rtinfo.rti_dst->sa_family]) == NULL) {
1635 		if (mycpuid != 0)
1636 			panic("partially initialized routing tables");
1637 		netisr_replymsg(&rmsg->base, EAFNOSUPPORT);
1638 		return;
1639 	}
1640 
1641 	/*
1642 	 * Correct rtinfo for the host route searching.
1643 	 */
1644 	if (rtinfo.rti_flags & RTF_HOST) {
1645 		rtinfo.rti_netmask = NULL;
1646 		rtinfo.rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
1647 	}
1648 
1649 	rt = (struct rtentry *)
1650 	     rnh->rnh_lookup((char *)rtinfo.rti_dst,
1651 			     (char *)rtinfo.rti_netmask, rnh);
1652 
1653 	/*
1654 	 * If we are asked to do the "exact match", we need to make sure
1655 	 * that host route searching got a host route while a network
1656 	 * route searching got a network route.
1657 	 */
1658 	if (rt != NULL && rmsg->exact_match &&
1659 	    ((rt->rt_flags ^ rtinfo.rti_flags) & RTF_HOST))
1660 		rt = NULL;
1661 
1662 	if (rt == NULL) {
1663 		/*
1664 		 * No matching routes have been found, don't count this
1665 		 * as a critical error (here, we set 'error' to 0), just
1666 		 * keep moving on, since at least prcloned routes are not
1667 		 * duplicated onto each CPU.
1668 		 */
1669 		error = 0;
1670 	} else {
1671 		rmsg->found_cnt++;
1672 
1673 		rt->rt_refcnt++;
1674 		error = rmsg->callback(rmsg->req, &rtinfo, rt, rmsg->arg,
1675 				      rmsg->found_cnt);
1676 		rt->rt_refcnt--;
1677 
1678 		if (error == EJUSTRETURN) {
1679 			netisr_replymsg(&rmsg->base, 0);
1680 			return;
1681 		}
1682 	}
1683 
1684 	if (error) {
1685 		KKASSERT(rmsg->found_cnt > 0);
1686 
1687 		/*
1688 		 * Under following cases, unrecoverable error has
1689 		 * not occured:
1690 		 * o  Request is RTM_GET
1691 		 * o  The first time that we find the route, but the
1692 		 *    modification fails.
1693 		 */
1694 		if (rmsg->req != RTM_GET && rmsg->found_cnt > 1) {
1695 			panic("rtsearch_msghandler: unrecoverable error "
1696 			      "cpu %d", mycpuid);
1697 		}
1698 		netisr_replymsg(&rmsg->base, error);
1699 	} else {
1700 		if (rmsg->found_cnt == 0) {
1701 			/* The requested route has not been seen ... */
1702 			error = ESRCH;
1703 		}
1704 		netisr_forwardmsg_error(&rmsg->base, mycpuid + 1, error);
1705 	}
1706 }
1707 
1708 int
1709 rtmask_add_global(struct sockaddr *mask, boolean_t req_prio)
1710 {
1711 	struct netmsg_base msg;
1712 	int flags = 0;
1713 
1714 	if (req_prio)
1715 		flags = MSGF_PRIORITY;
1716 	netmsg_init(&msg, NULL, &curthread->td_msgport, flags,
1717 	    rtmask_add_msghandler);
1718 	msg.lmsg.u.ms_resultp = mask;
1719 
1720 	return (netisr_domsg_global(&msg));
1721 }
1722 
1723 struct sockaddr *
1724 _rtmask_lookup(struct sockaddr *mask, boolean_t search)
1725 {
1726 	struct radix_node *n;
1727 
1728 #define	clen(s)	(*(u_char *)(s))
1729 	n = rn_addmask((char *)mask, search, 1, rn_cpumaskhead(mycpuid));
1730 	if (n != NULL &&
1731 	    mask->sa_len >= clen(n->rn_key) &&
1732 	    bcmp((char *)mask + 1,
1733 		 (char *)n->rn_key + 1, clen(n->rn_key) - 1) == 0) {
1734 		return (struct sockaddr *)n->rn_key;
1735 	} else {
1736 		return NULL;
1737 	}
1738 #undef clen
1739 }
1740 
1741 static void
1742 rtmask_add_msghandler(netmsg_t msg)
1743 {
1744 	struct sockaddr *mask = msg->lmsg.u.ms_resultp;
1745 
1746 	ASSERT_NETISR_NCPUS(mycpuid);
1747 
1748 	if (rtmask_lookup(mask) == NULL) {
1749 		netisr_replymsg(&msg->base, ENOBUFS);
1750 		return;
1751 	}
1752 	netisr_forwardmsg(&msg->base, mycpuid + 1);
1753 }
1754 
1755 /* This must be before ip6_init2(), which is now SI_ORDER_MIDDLE */
1756 SYSINIT(route, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, 0);
1757 
1758 struct rtchange_arg {
1759 	struct ifaddr	*old_ifa;
1760 	struct ifaddr	*new_ifa;
1761 	struct rtentry	*rt;
1762 	int		changed;
1763 };
1764 
1765 static void
1766 rtchange_ifa(struct rtentry *rt, struct rtchange_arg *ap)
1767 {
1768 	if (rt->rt_ifa->ifa_rtrequest != NULL)
1769 		rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt);
1770 	IFAFREE(rt->rt_ifa);
1771 
1772 	IFAREF(ap->new_ifa);
1773 	rt->rt_ifa = ap->new_ifa;
1774 	rt->rt_ifp = ap->new_ifa->ifa_ifp;
1775 	if (rt->rt_ifa->ifa_rtrequest != NULL)
1776 		rt->rt_ifa->ifa_rtrequest(RTM_ADD, rt);
1777 
1778 	ap->changed = 1;
1779 }
1780 
1781 static int
1782 rtchange_callback(struct radix_node *rn, void *xap)
1783 {
1784 	struct rtchange_arg *ap = xap;
1785 	struct rtentry *rt = (struct rtentry *)rn;
1786 
1787 	if (rt->rt_ifa == ap->old_ifa) {
1788 		if (rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) {
1789 			/*
1790 			 * We could saw the branch off when we are
1791 			 * still sitting on it, if the ifa_rtrequest
1792 			 * DEL/ADD are called directly from here.
1793 			 */
1794 			ap->rt = rt;
1795 			return EJUSTRETURN;
1796 		}
1797 		rtchange_ifa(rt, ap);
1798 	}
1799 	return 0;
1800 }
1801 
1802 struct netmsg_rtchange {
1803 	struct netmsg_base	base;
1804 	struct ifaddr		*old_ifa;
1805 	struct ifaddr		*new_ifa;
1806 	int			changed;
1807 };
1808 
1809 static void
1810 rtchange_dispatch(netmsg_t msg)
1811 {
1812 	struct netmsg_rtchange *rmsg = (void *)msg;
1813 	struct radix_node_head *rnh;
1814 	struct rtchange_arg arg;
1815 	int cpu;
1816 
1817 	cpu = mycpuid;
1818 	ASSERT_NETISR_NCPUS(cpu);
1819 
1820 	memset(&arg, 0, sizeof(arg));
1821 	arg.old_ifa = rmsg->old_ifa;
1822 	arg.new_ifa = rmsg->new_ifa;
1823 
1824 	rnh = rt_tables[cpu][AF_INET];
1825 	for (;;) {
1826 		int error;
1827 
1828 		KKASSERT(arg.rt == NULL);
1829 		error = rnh->rnh_walktree(rnh, rtchange_callback, &arg);
1830 		if (arg.rt != NULL) {
1831 			struct rtentry *rt;
1832 
1833 			rt = arg.rt;
1834 			arg.rt = NULL;
1835 			rtchange_ifa(rt, &arg);
1836 		} else {
1837 			break;
1838 		}
1839 	}
1840 	if (arg.changed)
1841 		rmsg->changed = 1;
1842 
1843 	netisr_forwardmsg(&rmsg->base, cpu + 1);
1844 }
1845 
1846 int
1847 rtchange(struct ifaddr *old_ifa, struct ifaddr *new_ifa)
1848 {
1849 	struct netmsg_rtchange msg;
1850 
1851 	/*
1852 	 * XXX individual requests are not independantly chained,
1853 	 * which means that the per-cpu route tables will not be
1854 	 * consistent in the middle of the operation.  If routes
1855 	 * related to the interface are manipulated while we are
1856 	 * doing this the inconsistancy could trigger a panic.
1857 	 */
1858 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, MSGF_PRIORITY,
1859 	    rtchange_dispatch);
1860 	msg.old_ifa = old_ifa;
1861 	msg.new_ifa = new_ifa;
1862 	msg.changed = 0;
1863 	netisr_domsg_global(&msg.base);
1864 
1865 	if (msg.changed) {
1866 		old_ifa->ifa_flags &= ~IFA_ROUTE;
1867 		new_ifa->ifa_flags |= IFA_ROUTE;
1868 		return 0;
1869 	} else {
1870 		return ENOENT;
1871 	}
1872 }
1873