xref: /dragonfly/sys/net/route.c (revision a3127495)
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/route.h>
81 #include <net/netisr.h>
82 
83 #include <netinet/in.h>
84 #include <net/ip_mroute/ip_mroute.h>
85 
86 #include <sys/thread2.h>
87 #include <sys/msgport2.h>
88 #include <net/netmsg2.h>
89 #include <net/netisr2.h>
90 
91 #ifdef MPLS
92 #include <netproto/mpls/mpls.h>
93 #endif
94 
95 static struct rtstatistics rtstatistics_percpu[MAXCPU] __cachealign;
96 #define rtstat	rtstatistics_percpu[mycpuid]
97 
98 struct radix_node_head *rt_tables[MAXCPU][AF_MAX+1];
99 
100 static void	rt_maskedcopy (struct sockaddr *, struct sockaddr *,
101 			       struct sockaddr *);
102 static void rtable_init(void);
103 static void rtinit_rtrequest_callback(int, int, struct rt_addrinfo *,
104 				      struct rtentry *, void *);
105 
106 static void rtredirect_msghandler(netmsg_t msg);
107 static void rtrequest1_msghandler(netmsg_t msg);
108 static void rtsearch_msghandler(netmsg_t msg);
109 static void rtmask_add_msghandler(netmsg_t msg);
110 
111 static int rt_setshims(struct rtentry *, struct sockaddr **);
112 
113 SYSCTL_NODE(_net, OID_AUTO, route, CTLFLAG_RW, 0, "Routing");
114 
115 #ifdef ROUTE_DEBUG
116 static int route_debug = 1;
117 SYSCTL_INT(_net_route, OID_AUTO, route_debug, CTLFLAG_RW,
118            &route_debug, 0, "");
119 #endif
120 
121 u_long route_kmalloc_limit = 0;
122 TUNABLE_ULONG("net.route.kmalloc_limit", &route_kmalloc_limit);
123 
124 /*
125  * Initialize the route table(s) for protocol domains and
126  * create a helper thread which will be responsible for updating
127  * route table entries on each cpu.
128  */
129 void
130 route_init(void)
131 {
132 	int cpu;
133 
134 	if (route_kmalloc_limit)
135 		kmalloc_raise_limit(M_RTABLE, route_kmalloc_limit);
136 
137 	for (cpu = 0; cpu < netisr_ncpus; ++cpu)
138 		bzero(&rtstatistics_percpu[cpu], sizeof(struct rtstatistics));
139 	rn_init();      /* initialize all zeroes, all ones, mask table */
140 	rtable_init();	/* call dom_rtattach() on each cpu */
141 }
142 
143 static void
144 rtable_init_oncpu(netmsg_t msg)
145 {
146 	struct domain *dom;
147 	int cpu = mycpuid;
148 
149 	ASSERT_NETISR_NCPUS(cpu);
150 
151 	SLIST_FOREACH(dom, &domains, dom_next) {
152 		if (dom->dom_rtattach) {
153 			dom->dom_rtattach(
154 				(void **)&rt_tables[cpu][dom->dom_family],
155 			        dom->dom_rtoffset);
156 		}
157 	}
158 	netisr_forwardmsg(&msg->base, cpu + 1);
159 }
160 
161 static void
162 rtable_init(void)
163 {
164 	struct netmsg_base msg;
165 
166 	netmsg_init(&msg, NULL, &curthread->td_msgport, 0, rtable_init_oncpu);
167 	netisr_domsg_global(&msg);
168 }
169 
170 /*
171  * Routing statistics.
172  */
173 static int
174 sysctl_rtstatistics(SYSCTL_HANDLER_ARGS)
175 {
176 	int cpu, error = 0;
177 
178 	for (cpu = 0; cpu < netisr_ncpus; ++cpu) {
179 		if ((error = SYSCTL_OUT(req, &rtstatistics_percpu[cpu],
180 					sizeof(struct rtstatistics))))
181 				break;
182 		if ((error = SYSCTL_IN(req, &rtstatistics_percpu[cpu],
183 					sizeof(struct rtstatistics))))
184 				break;
185 	}
186 
187 	return (error);
188 }
189 SYSCTL_PROC(_net_route, OID_AUTO, stats, (CTLTYPE_OPAQUE|CTLFLAG_RW),
190 	0, 0, sysctl_rtstatistics, "S,rtstatistics", "Routing statistics");
191 
192 /*
193  * Packet routing routines.
194  */
195 
196 /*
197  * Look up and fill in the "ro_rt" rtentry field in a route structure given
198  * an address in the "ro_dst" field.  Always send a report on a miss and
199  * always clone routes.
200  */
201 void
202 rtalloc(struct route *ro)
203 {
204 	rtalloc_ign(ro, 0UL);
205 }
206 
207 /*
208  * Look up and fill in the "ro_rt" rtentry field in a route structure given
209  * an address in the "ro_dst" field.  Always send a report on a miss and
210  * optionally clone routes when RTF_CLONING or RTF_PRCLONING are not being
211  * ignored.
212  */
213 void
214 rtalloc_ign(struct route *ro, u_long ignoreflags)
215 {
216 	if (ro->ro_rt != NULL) {
217 		if (ro->ro_rt->rt_ifp != NULL && ro->ro_rt->rt_flags & RTF_UP)
218 			return;
219 		rtfree(ro->ro_rt);
220 		ro->ro_rt = NULL;
221 	}
222 	ro->ro_rt = _rtlookup(&ro->ro_dst, RTL_REPORTMSG, ignoreflags);
223 }
224 
225 /*
226  * Look up the route that matches the given "dst" address.
227  *
228  * Route lookup can have the side-effect of creating and returning
229  * a cloned route instead when "dst" matches a cloning route and the
230  * RTF_CLONING and RTF_PRCLONING flags are not being ignored.
231  *
232  * Any route returned has its reference count incremented.
233  */
234 struct rtentry *
235 _rtlookup(struct sockaddr *dst, boolean_t generate_report, u_long ignore)
236 {
237 	struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
238 	struct rtentry *rt;
239 
240 	ASSERT_NETISR_NCPUS(mycpuid);
241 
242 	if (rnh == NULL)
243 		goto unreach;
244 
245 	/*
246 	 * Look up route in the radix tree.
247 	 */
248 	rt = (struct rtentry *) rnh->rnh_matchaddr((char *)dst, rnh);
249 	if (rt == NULL)
250 		goto unreach;
251 
252 	/*
253 	 * Handle cloning routes.
254 	 */
255 	if ((rt->rt_flags & ~ignore & (RTF_CLONING | RTF_PRCLONING)) != 0) {
256 		struct rtentry *clonedroute;
257 		int error;
258 
259 		clonedroute = rt;	/* copy in/copy out parameter */
260 		error = rtrequest(RTM_RESOLVE, dst, NULL, NULL, 0,
261 				  &clonedroute);	/* clone the route */
262 		if (error != 0) {	/* cloning failed */
263 			if (generate_report)
264 				rt_dstmsg(RTM_MISS, dst, error);
265 			rt->rt_refcnt++;
266 			return (rt);	/* return the uncloned route */
267 		}
268 		if (generate_report) {
269 			if (clonedroute->rt_flags & RTF_XRESOLVE)
270 				rt_dstmsg(RTM_RESOLVE, dst, 0);
271 			else
272 				rt_rtmsg(RTM_ADD, clonedroute,
273 					 clonedroute->rt_ifp, 0);
274 		}
275 		return (clonedroute);	/* return cloned route */
276 	}
277 
278 	/*
279 	 * Increment the reference count of the matched route and return.
280 	 */
281 	rt->rt_refcnt++;
282 	return (rt);
283 
284 unreach:
285 	rtstat.rts_unreach++;
286 	if (generate_report)
287 		rt_dstmsg(RTM_MISS, dst, 0);
288 	return (NULL);
289 }
290 
291 void
292 rtfree(struct rtentry *rt)
293 {
294 
295 	ASSERT_NETISR_NCPUS(rt->rt_cpuid);
296 	KASSERT(rt->rt_refcnt > 0, ("rtfree: rt_refcnt %ld", rt->rt_refcnt));
297 
298 	--rt->rt_refcnt;
299 	if (rt->rt_refcnt == 0) {
300 		struct radix_node_head *rnh =
301 		    rt_tables[mycpuid][rt_key(rt)->sa_family];
302 
303 		if (rnh->rnh_close)
304 			rnh->rnh_close((struct radix_node *)rt, rnh);
305 		if (!(rt->rt_flags & RTF_UP)) {
306 			/* deallocate route */
307 			if (rt->rt_ifa != NULL)
308 				IFAFREE(rt->rt_ifa);
309 			if (rt->rt_parent != NULL)
310 				RTFREE(rt->rt_parent);	/* recursive call! */
311 			Free(rt_key(rt));
312 			Free(rt);
313 		}
314 	}
315 }
316 
317 static void
318 rtfree_async_dispatch(netmsg_t msg)
319 {
320 	struct rtentry *rt = msg->lmsg.u.ms_resultp;
321 
322 	rtfree(rt);
323 	netisr_replymsg(&msg->base, 0);
324 }
325 
326 void
327 rtfree_async(struct rtentry *rt)
328 {
329 	struct netmsg_base *msg;
330 
331 	if (IN_NETISR_NCPUS(rt->rt_cpuid)) {
332 		rtfree(rt);
333 		return;
334 	}
335 
336 	KASSERT(rt->rt_refcnt > 0,
337 	    ("rtfree_async: rt_refcnt %ld", rt->rt_refcnt));
338 
339 	msg = kmalloc(sizeof(*msg), M_LWKTMSG, M_INTWAIT);
340 	netmsg_init(msg, NULL, &netisr_afree_rport, 0, rtfree_async_dispatch);
341 	msg->lmsg.u.ms_resultp = rt;
342 
343 	netisr_sendmsg(msg, rt->rt_cpuid);
344 }
345 
346 int
347 rtredirect_oncpu(struct sockaddr *dst, struct sockaddr *gateway,
348 		 struct sockaddr *netmask, int flags, struct sockaddr *src)
349 {
350 	struct rtentry *rt = NULL;
351 	struct rt_addrinfo rtinfo;
352 	struct ifaddr *ifa;
353 	u_long *stat = NULL;
354 	int error;
355 
356 	ASSERT_NETISR_NCPUS(mycpuid);
357 
358 	/* verify the gateway is directly reachable */
359 	if ((ifa = ifa_ifwithnet(gateway)) == NULL) {
360 		error = ENETUNREACH;
361 		goto out;
362 	}
363 
364 	/*
365 	 * If the redirect isn't from our current router for this destination,
366 	 * it's either old or wrong.
367 	 */
368 	if (!(flags & RTF_DONE) &&		/* XXX JH */
369 	    (rt = rtpurelookup(dst)) != NULL &&
370 	    (!sa_equal(src, rt->rt_gateway) || rt->rt_ifa != ifa)) {
371 		error = EINVAL;
372 		goto done;
373 	}
374 
375 	/*
376 	 * If it redirects us to ourselves, we have a routing loop,
377 	 * perhaps as a result of an interface going down recently.
378 	 */
379 	if (ifa_ifwithaddr(gateway)) {
380 		error = EHOSTUNREACH;
381 		goto done;
382 	}
383 
384 	/*
385 	 * Create a new entry if the lookup failed or if we got back
386 	 * a wildcard entry for the default route.  This is necessary
387 	 * for hosts which use routing redirects generated by smart
388 	 * gateways to dynamically build the routing tables.
389 	 */
390 	if (rt == NULL)
391 		goto create;
392 	if ((rt_mask(rt) != NULL && rt_mask(rt)->sa_len < 2)) {
393 		rtfree(rt);
394 		goto create;
395 	}
396 
397 	/* Ignore redirects for directly connected hosts. */
398 	if (!(rt->rt_flags & RTF_GATEWAY)) {
399 		error = EHOSTUNREACH;
400 		goto done;
401 	}
402 
403 	if (!(rt->rt_flags & RTF_HOST) && (flags & RTF_HOST)) {
404 		/*
405 		 * Changing from a network route to a host route.
406 		 * Create a new host route rather than smashing the
407 		 * network route.
408 		 */
409 create:
410 		flags |=  RTF_GATEWAY | RTF_DYNAMIC;
411 		bzero(&rtinfo, sizeof(struct rt_addrinfo));
412 		rtinfo.rti_info[RTAX_DST] = dst;
413 		rtinfo.rti_info[RTAX_GATEWAY] = gateway;
414 		rtinfo.rti_info[RTAX_NETMASK] = netmask;
415 		rtinfo.rti_flags = flags;
416 		rtinfo.rti_ifa = ifa;
417 		rt = NULL;	/* copy-in/copy-out parameter */
418 		error = rtrequest1(RTM_ADD, &rtinfo, &rt);
419 		if (rt != NULL)
420 			flags = rt->rt_flags;
421 		stat = &rtstat.rts_dynamic;
422 	} else {
423 		/*
424 		 * Smash the current notion of the gateway to this destination.
425 		 * Should check about netmask!!!
426 		 */
427 		rt->rt_flags |= RTF_MODIFIED;
428 		flags |= RTF_MODIFIED;
429 
430 		/* We only need to report rtmsg on CPU0 */
431 		rt_setgate(rt, rt_key(rt), gateway,
432 			   mycpuid == 0 ? RTL_REPORTMSG : RTL_DONTREPORT);
433 		error = 0;
434 		stat = &rtstat.rts_newgateway;
435 	}
436 
437 done:
438 	if (rt != NULL)
439 		rtfree(rt);
440 out:
441 	if (error != 0)
442 		rtstat.rts_badredirect++;
443 	else if (stat != NULL)
444 		(*stat)++;
445 
446 	return error;
447 }
448 
449 struct netmsg_rtredirect {
450 	struct netmsg_base base;
451 	struct sockaddr *dst;
452 	struct sockaddr *gateway;
453 	struct sockaddr *netmask;
454 	int		flags;
455 	struct sockaddr *src;
456 };
457 
458 /*
459  * Force a routing table entry to the specified
460  * destination to go through the given gateway.
461  * Normally called as a result of a routing redirect
462  * message from the network layer.
463  */
464 void
465 rtredirect(struct sockaddr *dst, struct sockaddr *gateway,
466 	   struct sockaddr *netmask, int flags, struct sockaddr *src)
467 {
468 	struct rt_addrinfo rtinfo;
469 	int error;
470 	struct netmsg_rtredirect msg;
471 
472 	netmsg_init(&msg.base, NULL, &curthread->td_msgport,
473 		    0, rtredirect_msghandler);
474 	msg.dst = dst;
475 	msg.gateway = gateway;
476 	msg.netmask = netmask;
477 	msg.flags = flags;
478 	msg.src = src;
479 	error = netisr_domsg_global(&msg.base);
480 
481 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
482 	rtinfo.rti_info[RTAX_DST] = dst;
483 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
484 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
485 	rtinfo.rti_info[RTAX_AUTHOR] = src;
486 	rt_missmsg(RTM_REDIRECT, &rtinfo, flags, error);
487 }
488 
489 static void
490 rtredirect_msghandler(netmsg_t msg)
491 {
492 	struct netmsg_rtredirect *rmsg = (void *)msg;
493 
494 	rtredirect_oncpu(rmsg->dst, rmsg->gateway, rmsg->netmask,
495 			 rmsg->flags, rmsg->src);
496 	netisr_forwardmsg(&msg->base, mycpuid + 1);
497 }
498 
499 /*
500 * Routing table ioctl interface.
501 */
502 int
503 rtioctl(u_long req, caddr_t data, struct ucred *cred)
504 {
505 #ifdef INET
506 	/* Multicast goop, grrr... */
507 	return mrt_ioctl ? mrt_ioctl(req, data) : EOPNOTSUPP;
508 #else
509 	return ENXIO;
510 #endif
511 }
512 
513 struct ifaddr *
514 ifa_ifwithroute(int flags, struct sockaddr *dst, struct sockaddr *gateway)
515 {
516 	struct ifaddr *ifa;
517 
518 	if (!(flags & RTF_GATEWAY)) {
519 		/*
520 		 * If we are adding a route to an interface,
521 		 * and the interface is a point-to-point link,
522 		 * we should search for the destination
523 		 * as our clue to the interface.  Otherwise
524 		 * we can use the local address.
525 		 */
526 		ifa = NULL;
527 		if (flags & RTF_HOST) {
528 			ifa = ifa_ifwithdstaddr(dst);
529 		}
530 		if (ifa == NULL)
531 			ifa = ifa_ifwithaddr(gateway);
532 	} else {
533 		/*
534 		 * If we are adding a route to a remote net
535 		 * or host, the gateway may still be on the
536 		 * other end of a pt to pt link.
537 		 */
538 		ifa = ifa_ifwithdstaddr(gateway);
539 	}
540 	if (ifa == NULL)
541 		ifa = ifa_ifwithnet(gateway);
542 	if (ifa == NULL) {
543 		struct rtentry *rt;
544 
545 		rt = rtpurelookup(gateway);
546 		if (rt == NULL)
547 			return (NULL);
548 		rt->rt_refcnt--;
549 		if ((ifa = rt->rt_ifa) == NULL)
550 			return (NULL);
551 	}
552 	if (ifa->ifa_addr->sa_family != dst->sa_family) {
553 		struct ifaddr *oldifa = ifa;
554 
555 		ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
556 		if (ifa == NULL)
557 			ifa = oldifa;
558 	}
559 	return (ifa);
560 }
561 
562 static int rt_fixdelete (struct radix_node *, void *);
563 static int rt_fixchange (struct radix_node *, void *);
564 
565 struct rtfc_arg {
566 	struct rtentry *rt0;
567 	struct radix_node_head *rnh;
568 };
569 
570 /*
571  * Set rtinfo->rti_ifa and rtinfo->rti_ifp.
572  */
573 int
574 rt_getifa(struct rt_addrinfo *rtinfo)
575 {
576 	struct sockaddr *gateway = rtinfo->rti_info[RTAX_GATEWAY];
577 	struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
578 	struct sockaddr *ifaaddr = rtinfo->rti_info[RTAX_IFA];
579 	int flags = rtinfo->rti_flags;
580 
581 	/*
582 	 * ifp may be specified by sockaddr_dl
583 	 * when protocol address is ambiguous.
584 	 */
585 	if (rtinfo->rti_ifp == NULL) {
586 		struct sockaddr *ifpaddr;
587 
588 		ifpaddr = rtinfo->rti_info[RTAX_IFP];
589 		if (ifpaddr != NULL && ifpaddr->sa_family == AF_LINK) {
590 			struct ifaddr *ifa;
591 
592 			ifa = ifa_ifwithnet(ifpaddr);
593 			if (ifa != NULL)
594 				rtinfo->rti_ifp = ifa->ifa_ifp;
595 		}
596 	}
597 
598 	if (rtinfo->rti_ifa == NULL && ifaaddr != NULL)
599 		rtinfo->rti_ifa = ifa_ifwithaddr(ifaaddr);
600 	if (rtinfo->rti_ifa == NULL) {
601 		struct sockaddr *sa;
602 
603 		sa = ifaaddr != NULL ? ifaaddr :
604 		    (gateway != NULL ? gateway : dst);
605 		if (sa != NULL && rtinfo->rti_ifp != NULL)
606 			rtinfo->rti_ifa = ifaof_ifpforaddr(sa, rtinfo->rti_ifp);
607 		else if (dst != NULL && gateway != NULL)
608 			rtinfo->rti_ifa = ifa_ifwithroute(flags, dst, gateway);
609 		else if (sa != NULL)
610 			rtinfo->rti_ifa = ifa_ifwithroute(flags, sa, sa);
611 	}
612 	if (rtinfo->rti_ifa == NULL)
613 		return (ENETUNREACH);
614 
615 	if (rtinfo->rti_ifp == NULL)
616 		rtinfo->rti_ifp = rtinfo->rti_ifa->ifa_ifp;
617 	return (0);
618 }
619 
620 /*
621  * Do appropriate manipulations of a routing tree given
622  * all the bits of info needed
623  */
624 int
625 rtrequest(
626 	int req,
627 	struct sockaddr *dst,
628 	struct sockaddr *gateway,
629 	struct sockaddr *netmask,
630 	int flags,
631 	struct rtentry **ret_nrt)
632 {
633 	struct rt_addrinfo rtinfo;
634 
635 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
636 	rtinfo.rti_info[RTAX_DST] = dst;
637 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
638 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
639 	rtinfo.rti_flags = flags;
640 	return rtrequest1(req, &rtinfo, ret_nrt);
641 }
642 
643 int
644 rtrequest_global(
645 	int req,
646 	struct sockaddr *dst,
647 	struct sockaddr *gateway,
648 	struct sockaddr *netmask,
649 	int flags)
650 {
651 	struct rt_addrinfo rtinfo;
652 
653 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
654 	rtinfo.rti_info[RTAX_DST] = dst;
655 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
656 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
657 	rtinfo.rti_flags = flags;
658 	return rtrequest1_global(req, &rtinfo, NULL, NULL, RTREQ_PRIO_NORM);
659 }
660 
661 struct netmsg_rtq {
662 	struct netmsg_base	base;
663 	int			req;
664 	struct rt_addrinfo	*rtinfo;
665 	rtrequest1_callback_func_t callback;
666 	void			*arg;
667 };
668 
669 int
670 rtrequest1_global(int req, struct rt_addrinfo *rtinfo,
671     rtrequest1_callback_func_t callback, void *arg, boolean_t req_prio)
672 {
673 	struct netmsg_rtq msg;
674 	int flags = 0;
675 
676 	if (req_prio)
677 		flags = MSGF_PRIORITY;
678 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
679 	    rtrequest1_msghandler);
680 	msg.base.lmsg.ms_error = -1;
681 	msg.req = req;
682 	msg.rtinfo = rtinfo;
683 	msg.callback = callback;
684 	msg.arg = arg;
685 	return (netisr_domsg_global(&msg.base));
686 }
687 
688 /*
689  * Handle a route table request on the current cpu.  Since the route table's
690  * are supposed to be identical on each cpu, an error occuring later in the
691  * message chain is considered system-fatal.
692  */
693 static void
694 rtrequest1_msghandler(netmsg_t msg)
695 {
696 	struct netmsg_rtq *rmsg = (void *)msg;
697 	struct rt_addrinfo rtinfo;
698 	struct rtentry *rt = NULL;
699 	int error;
700 
701 	/*
702 	 * Copy the rtinfo.  We need to make sure that the original
703 	 * rtinfo, which is setup by the caller, in the netmsg will
704 	 * _not_ be changed; else the next CPU on the netmsg forwarding
705 	 * path will see a different rtinfo than what this CPU has seen.
706 	 */
707 	rtinfo = *rmsg->rtinfo;
708 
709 	error = rtrequest1(rmsg->req, &rtinfo, &rt);
710 	if (rt)
711 		--rt->rt_refcnt;
712 	if (rmsg->callback)
713 		rmsg->callback(rmsg->req, error, &rtinfo, rt, rmsg->arg);
714 
715 	/*
716 	 * RTM_DELETE's are propogated even if an error occurs, since a
717 	 * cloned route might be undergoing deletion and cloned routes
718 	 * are not necessarily replicated.  An overall error is returned
719 	 * only if no cpus have the route in question.
720 	 */
721 	if (rmsg->base.lmsg.ms_error < 0 || error == 0)
722 		rmsg->base.lmsg.ms_error = error;
723 
724 	if (error && rmsg->req != RTM_DELETE) {
725 		if (mycpuid != 0) {
726 			panic("rtrequest1_msghandler: rtrequest table req %d, "
727 			    "failed on cpu%d, error %d\n",
728 			    rmsg->req, mycpuid, error);
729 		}
730 		netisr_replymsg(&rmsg->base, error);
731 	} else {
732 		netisr_forwardmsg_error(&rmsg->base, mycpuid + 1,
733 		    rmsg->base.lmsg.ms_error);
734 	}
735 }
736 
737 int
738 rtrequest1(int req, struct rt_addrinfo *rtinfo, struct rtentry **ret_nrt)
739 {
740 	struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
741 	struct rtentry *rt;
742 	struct radix_node *rn;
743 	struct radix_node_head *rnh;
744 	struct ifaddr *ifa;
745 	struct sockaddr *ndst;
746 	boolean_t reportmsg;
747 	int error = 0;
748 
749 	ASSERT_NETISR_NCPUS(mycpuid);
750 
751 #define gotoerr(x) { error = x ; goto bad; }
752 
753 #ifdef ROUTE_DEBUG
754 	if (route_debug)
755 		rt_addrinfo_print(req, rtinfo);
756 #endif
757 
758 	crit_enter();
759 	/*
760 	 * Find the correct routing tree to use for this Address Family
761 	 */
762 	if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL)
763 		gotoerr(EAFNOSUPPORT);
764 
765 	/*
766 	 * If we are adding a host route then we don't want to put
767 	 * a netmask in the tree, nor do we want to clone it.
768 	 */
769 	if (rtinfo->rti_flags & RTF_HOST) {
770 		rtinfo->rti_info[RTAX_NETMASK] = NULL;
771 		rtinfo->rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
772 	}
773 
774 	switch (req) {
775 	case RTM_DELETE:
776 		/* Remove the item from the tree. */
777 		rn = rnh->rnh_deladdr((char *)rtinfo->rti_info[RTAX_DST],
778 				      (char *)rtinfo->rti_info[RTAX_NETMASK],
779 				      rnh);
780 		if (rn == NULL)
781 			gotoerr(ESRCH);
782 		KASSERT(!(rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)),
783 			("rnh_deladdr returned flags 0x%x", rn->rn_flags));
784 		rt = (struct rtentry *)rn;
785 
786 		/* ref to prevent a deletion race */
787 		++rt->rt_refcnt;
788 
789 		/* Free any routes cloned from this one. */
790 		if ((rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) &&
791 		    rt_mask(rt) != NULL) {
792 			rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
793 					       (char *)rt_mask(rt),
794 					       rt_fixdelete, rt);
795 		}
796 
797 		if (rt->rt_gwroute != NULL) {
798 			RTFREE(rt->rt_gwroute);
799 			rt->rt_gwroute = NULL;
800 		}
801 
802 		/*
803 		 * NB: RTF_UP must be set during the search above,
804 		 * because we might delete the last ref, causing
805 		 * rt to get freed prematurely.
806 		 */
807 		rt->rt_flags &= ~RTF_UP;
808 
809 #ifdef ROUTE_DEBUG
810 		if (route_debug)
811 			rt_print(rtinfo, rt);
812 #endif
813 
814 		/* Give the protocol a chance to keep things in sync. */
815 		if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
816 			ifa->ifa_rtrequest(RTM_DELETE, rt);
817 
818 		/*
819 		 * If the caller wants it, then it can have it,
820 		 * but it's up to it to free the rtentry as we won't be
821 		 * doing it.
822 		 */
823 		KASSERT(rt->rt_refcnt >= 0,
824 			("rtrequest1(DELETE): refcnt %ld", rt->rt_refcnt));
825 		if (ret_nrt != NULL) {
826 			/* leave ref intact for return */
827 			*ret_nrt = rt;
828 		} else {
829 			/* deref / attempt to destroy */
830 			rtfree(rt);
831 		}
832 		break;
833 
834 	case RTM_RESOLVE:
835 		if (ret_nrt == NULL || (rt = *ret_nrt) == NULL)
836 			gotoerr(EINVAL);
837 
838 		KASSERT(rt->rt_cpuid == mycpuid,
839 		    ("rt resolve rt_cpuid %d, mycpuid %d",
840 		     rt->rt_cpuid, mycpuid));
841 
842 		ifa = rt->rt_ifa;
843 		rtinfo->rti_flags =
844 		    rt->rt_flags & ~(RTF_CLONING | RTF_PRCLONING | RTF_STATIC);
845 		rtinfo->rti_flags |= RTF_WASCLONED;
846 		rtinfo->rti_info[RTAX_GATEWAY] = rt->rt_gateway;
847 		if ((rtinfo->rti_info[RTAX_NETMASK] = rt->rt_genmask) == NULL)
848 			rtinfo->rti_flags |= RTF_HOST;
849 		rtinfo->rti_info[RTAX_MPLS1] = rt->rt_shim[0];
850 		rtinfo->rti_info[RTAX_MPLS2] = rt->rt_shim[1];
851 		rtinfo->rti_info[RTAX_MPLS3] = rt->rt_shim[2];
852 		goto makeroute;
853 
854 	case RTM_ADD:
855 		KASSERT(!(rtinfo->rti_flags & RTF_GATEWAY) ||
856 			rtinfo->rti_info[RTAX_GATEWAY] != NULL,
857 		    ("rtrequest: GATEWAY but no gateway"));
858 
859 		if (rtinfo->rti_ifa == NULL && (error = rt_getifa(rtinfo)))
860 			gotoerr(error);
861 		ifa = rtinfo->rti_ifa;
862 makeroute:
863 		R_Malloc(rt, struct rtentry *, sizeof(struct rtentry));
864 		if (rt == NULL) {
865 			if (req == RTM_ADD) {
866 				kprintf("rtrequest1: alloc rtentry failed on "
867 				    "cpu%d\n", mycpuid);
868 			}
869 			gotoerr(ENOBUFS);
870 		}
871 		bzero(rt, sizeof(struct rtentry));
872 		rt->rt_flags = RTF_UP | rtinfo->rti_flags;
873 		rt->rt_cpuid = mycpuid;
874 
875 		if (mycpuid != 0 && req == RTM_ADD) {
876 			/* For RTM_ADD, we have already sent rtmsg on CPU0. */
877 			reportmsg = RTL_DONTREPORT;
878 		} else {
879 			/*
880 			 * For RTM_ADD, we only send rtmsg on CPU0.
881 			 * For RTM_RESOLVE, we always send rtmsg. XXX
882 			 */
883 			reportmsg = RTL_REPORTMSG;
884 		}
885 		error = rt_setgate(rt, dst, rtinfo->rti_info[RTAX_GATEWAY],
886 				   reportmsg);
887 		if (error != 0) {
888 			Free(rt);
889 			gotoerr(error);
890 		}
891 
892 		ndst = rt_key(rt);
893 		if (rtinfo->rti_info[RTAX_NETMASK] != NULL)
894 			rt_maskedcopy(dst, ndst,
895 				      rtinfo->rti_info[RTAX_NETMASK]);
896 		else
897 			bcopy(dst, ndst, dst->sa_len);
898 
899 		if (rtinfo->rti_info[RTAX_MPLS1] != NULL)
900 			rt_setshims(rt, rtinfo->rti_info);
901 
902 		/*
903 		 * Note that we now have a reference to the ifa.
904 		 * This moved from below so that rnh->rnh_addaddr() can
905 		 * examine the ifa and  ifa->ifa_ifp if it so desires.
906 		 */
907 		IFAREF(ifa);
908 		rt->rt_ifa = ifa;
909 		rt->rt_ifp = ifa->ifa_ifp;
910 		/* XXX mtu manipulation will be done in rnh_addaddr -- itojun */
911 
912 		rn = rnh->rnh_addaddr((char *)ndst,
913 				      (char *)rtinfo->rti_info[RTAX_NETMASK],
914 				      rnh, rt->rt_nodes);
915 		if (rn == NULL) {
916 			struct rtentry *oldrt;
917 
918 			/*
919 			 * We already have one of these in the tree.
920 			 * We do a special hack: if the old route was
921 			 * cloned, then we blow it away and try
922 			 * re-inserting the new one.
923 			 */
924 			oldrt = rtpurelookup(ndst);
925 			if (oldrt != NULL) {
926 				--oldrt->rt_refcnt;
927 				if (oldrt->rt_flags & RTF_WASCLONED) {
928 					rtrequest(RTM_DELETE, rt_key(oldrt),
929 						  oldrt->rt_gateway,
930 						  rt_mask(oldrt),
931 						  oldrt->rt_flags, NULL);
932 					rn = rnh->rnh_addaddr((char *)ndst,
933 					    (char *)
934 						rtinfo->rti_info[RTAX_NETMASK],
935 					    rnh, rt->rt_nodes);
936 				}
937 			}
938 		}
939 		/* NOTE: rt_ifa may have been changed */
940 		ifa = rt->rt_ifa;
941 
942 		/*
943 		 * If it still failed to go into the tree,
944 		 * then un-make it (this should be a function).
945 		 */
946 		if (rn == NULL) {
947 			if (rt->rt_gwroute != NULL)
948 				rtfree(rt->rt_gwroute);
949 			IFAFREE(ifa);
950 			Free(rt_key(rt));
951 			Free(rt);
952 			gotoerr(EEXIST);
953 		}
954 
955 		/*
956 		 * If we got here from RESOLVE, then we are cloning
957 		 * so clone the rest, and note that we
958 		 * are a clone (and increment the parent's references)
959 		 */
960 		if (req == RTM_RESOLVE) {
961 			rt->rt_rmx = (*ret_nrt)->rt_rmx;    /* copy metrics */
962 			rt->rt_rmx.rmx_pksent = 0;  /* reset packet counter */
963 			if ((*ret_nrt)->rt_flags &
964 				       (RTF_CLONING | RTF_PRCLONING)) {
965 				rt->rt_parent = *ret_nrt;
966 				(*ret_nrt)->rt_refcnt++;
967 			}
968 		}
969 
970 		/*
971 		 * if this protocol has something to add to this then
972 		 * allow it to do that as well.
973 		 */
974 		if (ifa->ifa_rtrequest != NULL)
975 			ifa->ifa_rtrequest(req, rt);
976 
977 		/*
978 		 * We repeat the same procedure from rt_setgate() here because
979 		 * it doesn't fire when we call it there because the node
980 		 * hasn't been added to the tree yet.
981 		 */
982 		if (req == RTM_ADD && !(rt->rt_flags & RTF_HOST) &&
983 		    rt_mask(rt) != NULL) {
984 			struct rtfc_arg arg = { rt, rnh };
985 
986 			rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
987 					       (char *)rt_mask(rt),
988 					       rt_fixchange, &arg);
989 		}
990 
991 #ifdef ROUTE_DEBUG
992 		if (route_debug)
993 			rt_print(rtinfo, rt);
994 #endif
995 		/*
996 		 * Return the resulting rtentry,
997 		 * increasing the number of references by one.
998 		 */
999 		if (ret_nrt != NULL) {
1000 			rt->rt_refcnt++;
1001 			*ret_nrt = rt;
1002 		}
1003 		break;
1004 	default:
1005 		error = EOPNOTSUPP;
1006 	}
1007 bad:
1008 #ifdef ROUTE_DEBUG
1009 	if (route_debug) {
1010 		if (error)
1011 			kprintf("rti %p failed error %d\n", rtinfo, error);
1012 		else
1013 			kprintf("rti %p succeeded\n", rtinfo);
1014 	}
1015 #endif
1016 	crit_exit();
1017 	return (error);
1018 }
1019 
1020 /*
1021  * Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family''
1022  * (i.e., the routes related to it by the operation of cloning).  This
1023  * routine is iterated over all potential former-child-routes by way of
1024  * rnh->rnh_walktree_from() above, and those that actually are children of
1025  * the late parent (passed in as VP here) are themselves deleted.
1026  */
1027 static int
1028 rt_fixdelete(struct radix_node *rn, void *vp)
1029 {
1030 	struct rtentry *rt = (struct rtentry *)rn;
1031 	struct rtentry *rt0 = vp;
1032 
1033 	if (rt->rt_parent == rt0 &&
1034 	    !(rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1035 		return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1036 				 rt->rt_flags, NULL);
1037 	}
1038 	return 0;
1039 }
1040 
1041 /*
1042  * This routine is called from rt_setgate() to do the analogous thing for
1043  * adds and changes.  There is the added complication in this case of a
1044  * middle insert; i.e., insertion of a new network route between an older
1045  * network route and (cloned) host routes.  For this reason, a simple check
1046  * of rt->rt_parent is insufficient; each candidate route must be tested
1047  * against the (mask, value) of the new route (passed as before in vp)
1048  * to see if the new route matches it.
1049  *
1050  * XXX - it may be possible to do fixdelete() for changes and reserve this
1051  * routine just for adds.  I'm not sure why I thought it was necessary to do
1052  * changes this way.
1053  */
1054 #ifdef DEBUG
1055 static int rtfcdebug = 0;
1056 #endif
1057 
1058 static int
1059 rt_fixchange(struct radix_node *rn, void *vp)
1060 {
1061 	struct rtentry *rt = (struct rtentry *)rn;
1062 	struct rtfc_arg *ap = vp;
1063 	struct rtentry *rt0 = ap->rt0;
1064 	struct radix_node_head *rnh = ap->rnh;
1065 	u_char *xk1, *xm1, *xk2, *xmp;
1066 	int i, len, mlen;
1067 
1068 #ifdef DEBUG
1069 	if (rtfcdebug)
1070 		kprintf("rt_fixchange: rt %p, rt0 %p\n", rt, rt0);
1071 #endif
1072 
1073 	if (rt->rt_parent == NULL ||
1074 	    (rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1075 #ifdef DEBUG
1076 		if (rtfcdebug) kprintf("no parent, pinned or cloning\n");
1077 #endif
1078 		return 0;
1079 	}
1080 
1081 	if (rt->rt_parent == rt0) {
1082 #ifdef DEBUG
1083 		if (rtfcdebug) kprintf("parent match\n");
1084 #endif
1085 		return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1086 				 rt->rt_flags, NULL);
1087 	}
1088 
1089 	/*
1090 	 * There probably is a function somewhere which does this...
1091 	 * if not, there should be.
1092 	 */
1093 	len = imin(rt_key(rt0)->sa_len, rt_key(rt)->sa_len);
1094 
1095 	xk1 = (u_char *)rt_key(rt0);
1096 	xm1 = (u_char *)rt_mask(rt0);
1097 	xk2 = (u_char *)rt_key(rt);
1098 
1099 	/* avoid applying a less specific route */
1100 	xmp = (u_char *)rt_mask(rt->rt_parent);
1101 	mlen = rt_key(rt->rt_parent)->sa_len;
1102 	if (mlen > rt_key(rt0)->sa_len) {
1103 #ifdef DEBUG
1104 		if (rtfcdebug)
1105 			kprintf("rt_fixchange: inserting a less "
1106 			       "specific route\n");
1107 #endif
1108 		return 0;
1109 	}
1110 	for (i = rnh->rnh_treetop->rn_offset; i < mlen; i++) {
1111 		if ((xmp[i] & ~(xmp[i] ^ xm1[i])) != xmp[i]) {
1112 #ifdef DEBUG
1113 			if (rtfcdebug)
1114 				kprintf("rt_fixchange: inserting a less "
1115 				       "specific route\n");
1116 #endif
1117 			return 0;
1118 		}
1119 	}
1120 
1121 	for (i = rnh->rnh_treetop->rn_offset; i < len; i++) {
1122 		if ((xk2[i] & xm1[i]) != xk1[i]) {
1123 #ifdef DEBUG
1124 			if (rtfcdebug) kprintf("no match\n");
1125 #endif
1126 			return 0;
1127 		}
1128 	}
1129 
1130 	/*
1131 	 * OK, this node is a clone, and matches the node currently being
1132 	 * changed/added under the node's mask.  So, get rid of it.
1133 	 */
1134 #ifdef DEBUG
1135 	if (rtfcdebug) kprintf("deleting\n");
1136 #endif
1137 	return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1138 			 rt->rt_flags, NULL);
1139 }
1140 
1141 int
1142 rt_setgate(struct rtentry *rt0, struct sockaddr *dst, struct sockaddr *gate,
1143 	   boolean_t generate_report)
1144 {
1145 	char *space, *oldspace;
1146 	int dlen = RT_ROUNDUP(dst->sa_len), glen = RT_ROUNDUP(gate->sa_len);
1147 	struct rtentry *rt = rt0;
1148 	struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
1149 
1150 	ASSERT_NETISR_NCPUS(mycpuid);
1151 
1152 	/*
1153 	 * A host route with the destination equal to the gateway
1154 	 * will interfere with keeping LLINFO in the routing
1155 	 * table, so disallow it.
1156 	 */
1157 	if (((rt0->rt_flags & (RTF_HOST | RTF_GATEWAY | RTF_LLINFO)) ==
1158 			      (RTF_HOST | RTF_GATEWAY)) &&
1159 	    dst->sa_len == gate->sa_len &&
1160 	    sa_equal(dst, gate)) {
1161 		/*
1162 		 * The route might already exist if this is an RTM_CHANGE
1163 		 * or a routing redirect, so try to delete it.
1164 		 */
1165 		if (rt_key(rt0) != NULL)
1166 			rtrequest(RTM_DELETE, rt_key(rt0), rt0->rt_gateway,
1167 				  rt_mask(rt0), rt0->rt_flags, NULL);
1168 		return EADDRNOTAVAIL;
1169 	}
1170 
1171 	/*
1172 	 * Both dst and gateway are stored in the same malloc'ed chunk
1173 	 * (If I ever get my hands on....)
1174 	 * if we need to malloc a new chunk, then keep the old one around
1175 	 * till we don't need it any more.
1176 	 */
1177 	if (rt->rt_gateway == NULL ||
1178 	    glen > RT_ROUNDUP(rt->rt_gateway->sa_len)) {
1179 		oldspace = (char *)rt_key(rt);
1180 		R_Malloc(space, char *, dlen + glen);
1181 		if (space == NULL)
1182 			return ENOBUFS;
1183 		rt->rt_nodes->rn_key = space;
1184 	} else {
1185 		space = (char *)rt_key(rt);	/* Just use the old space. */
1186 		oldspace = NULL;
1187 	}
1188 
1189 	/* Set the gateway value. */
1190 	rt->rt_gateway = (struct sockaddr *)(space + dlen);
1191 	bcopy(gate, rt->rt_gateway, glen);
1192 
1193 	if (oldspace != NULL) {
1194 		/*
1195 		 * If we allocated a new chunk, preserve the original dst.
1196 		 * This way, rt_setgate() really just sets the gate
1197 		 * and leaves the dst field alone.
1198 		 */
1199 		bcopy(dst, space, dlen);
1200 		Free(oldspace);
1201 	}
1202 
1203 	/*
1204 	 * If there is already a gwroute, it's now almost definitely wrong
1205 	 * so drop it.
1206 	 */
1207 	if (rt->rt_gwroute != NULL) {
1208 		RTFREE(rt->rt_gwroute);
1209 		rt->rt_gwroute = NULL;
1210 	}
1211 	if (rt->rt_flags & RTF_GATEWAY) {
1212 		/*
1213 		 * Cloning loop avoidance: In the presence of
1214 		 * protocol-cloning and bad configuration, it is
1215 		 * possible to get stuck in bottomless mutual recursion
1216 		 * (rtrequest rt_setgate rtlookup).  We avoid this
1217 		 * by not allowing protocol-cloning to operate for
1218 		 * gateways (which is probably the correct choice
1219 		 * anyway), and avoid the resulting reference loops
1220 		 * by disallowing any route to run through itself as
1221 		 * a gateway.  This is obviously mandatory when we
1222 		 * get rt->rt_output().
1223 		 *
1224 		 * This breaks TTCP for hosts outside the gateway!  XXX JH
1225 		 */
1226 		rt->rt_gwroute = _rtlookup(gate, generate_report,
1227 					   RTF_PRCLONING);
1228 		if (rt->rt_gwroute == rt) {
1229 			rt->rt_gwroute = NULL;
1230 			--rt->rt_refcnt;
1231 			return EDQUOT; /* failure */
1232 		}
1233 	}
1234 
1235 	/*
1236 	 * This isn't going to do anything useful for host routes, so
1237 	 * don't bother.  Also make sure we have a reasonable mask
1238 	 * (we don't yet have one during adds).
1239 	 */
1240 	if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != NULL) {
1241 		struct rtfc_arg arg = { rt, rnh };
1242 
1243 		rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
1244 				       (char *)rt_mask(rt),
1245 				       rt_fixchange, &arg);
1246 	}
1247 
1248 	return 0;
1249 }
1250 
1251 static void
1252 rt_maskedcopy(
1253 	struct sockaddr *src,
1254 	struct sockaddr *dst,
1255 	struct sockaddr *netmask)
1256 {
1257 	u_char *cp1 = (u_char *)src;
1258 	u_char *cp2 = (u_char *)dst;
1259 	u_char *cp3 = (u_char *)netmask;
1260 	u_char *cplim = cp2 + *cp3;
1261 	u_char *cplim2 = cp2 + *cp1;
1262 
1263 	*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
1264 	cp3 += 2;
1265 	if (cplim > cplim2)
1266 		cplim = cplim2;
1267 	while (cp2 < cplim)
1268 		*cp2++ = *cp1++ & *cp3++;
1269 	if (cp2 < cplim2)
1270 		bzero(cp2, cplim2 - cp2);
1271 }
1272 
1273 int
1274 rt_llroute(struct sockaddr *dst, struct rtentry *rt0, struct rtentry **drt)
1275 {
1276 	struct rtentry *up_rt, *rt;
1277 
1278 	ASSERT_NETISR_NCPUS(mycpuid);
1279 
1280 	if (!(rt0->rt_flags & RTF_UP)) {
1281 		up_rt = rtlookup(dst);
1282 		if (up_rt == NULL)
1283 			return (EHOSTUNREACH);
1284 		up_rt->rt_refcnt--;
1285 	} else
1286 		up_rt = rt0;
1287 	if (up_rt->rt_flags & RTF_GATEWAY) {
1288 		if (up_rt->rt_gwroute == NULL) {
1289 			up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1290 			if (up_rt->rt_gwroute == NULL)
1291 				return (EHOSTUNREACH);
1292 		} else if (!(up_rt->rt_gwroute->rt_flags & RTF_UP)) {
1293 			rtfree(up_rt->rt_gwroute);
1294 			up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1295 			if (up_rt->rt_gwroute == NULL)
1296 				return (EHOSTUNREACH);
1297 		}
1298 		rt = up_rt->rt_gwroute;
1299 	} else
1300 		rt = up_rt;
1301 	if (rt->rt_flags & RTF_REJECT &&
1302 	    (rt->rt_rmx.rmx_expire == 0 ||		/* rt doesn't expire */
1303 	     time_uptime < rt->rt_rmx.rmx_expire))	/* rt not expired */
1304 		return (rt->rt_flags & RTF_HOST ?  EHOSTDOWN : EHOSTUNREACH);
1305 	*drt = rt;
1306 	return 0;
1307 }
1308 
1309 static int
1310 rt_setshims(struct rtentry *rt, struct sockaddr **rt_shim){
1311 	int i;
1312 
1313 	for (i=0; i<3; i++) {
1314 		struct sockaddr *shim = rt_shim[RTAX_MPLS1 + i];
1315 		int shimlen;
1316 
1317 		if (shim == NULL)
1318 			break;
1319 
1320 		shimlen = RT_ROUNDUP(shim->sa_len);
1321 		R_Malloc(rt->rt_shim[i], struct sockaddr *, shimlen);
1322 		bcopy(shim, rt->rt_shim[i], shimlen);
1323 	}
1324 
1325 	return 0;
1326 }
1327 
1328 #ifdef ROUTE_DEBUG
1329 
1330 /*
1331  * Print out a route table entry
1332  */
1333 void
1334 rt_print(struct rt_addrinfo *rtinfo, struct rtentry *rn)
1335 {
1336 	kprintf("rti %p cpu %d route %p flags %08lx: ",
1337 		rtinfo, mycpuid, rn, rn->rt_flags);
1338 	sockaddr_print(rt_key(rn));
1339 	kprintf(" mask ");
1340 	sockaddr_print(rt_mask(rn));
1341 	kprintf(" gw ");
1342 	sockaddr_print(rn->rt_gateway);
1343 	kprintf(" ifc \"%s\"", rn->rt_ifp ? rn->rt_ifp->if_dname : "?");
1344 	kprintf(" ifa %p\n", rn->rt_ifa);
1345 }
1346 
1347 void
1348 rt_addrinfo_print(int cmd, struct rt_addrinfo *rti)
1349 {
1350 	int didit = 0;
1351 	int i;
1352 
1353 #ifdef ROUTE_DEBUG
1354 	if (cmd == RTM_DELETE && route_debug > 1)
1355 		print_backtrace(-1);
1356 #endif
1357 
1358 	switch(cmd) {
1359 	case RTM_ADD:
1360 		kprintf("ADD ");
1361 		break;
1362 	case RTM_RESOLVE:
1363 		kprintf("RES ");
1364 		break;
1365 	case RTM_DELETE:
1366 		kprintf("DEL ");
1367 		break;
1368 	default:
1369 		kprintf("C%02d ", cmd);
1370 		break;
1371 	}
1372 	kprintf("rti %p cpu %d ", rti, mycpuid);
1373 	for (i = 0; i < rti->rti_addrs; ++i) {
1374 		if (rti->rti_info[i] == NULL)
1375 			continue;
1376 		if (didit)
1377 			kprintf(" ,");
1378 		switch(i) {
1379 		case RTAX_DST:
1380 			kprintf("(DST ");
1381 			break;
1382 		case RTAX_GATEWAY:
1383 			kprintf("(GWY ");
1384 			break;
1385 		case RTAX_NETMASK:
1386 			kprintf("(MSK ");
1387 			break;
1388 		case RTAX_GENMASK:
1389 			kprintf("(GEN ");
1390 			break;
1391 		case RTAX_IFP:
1392 			kprintf("(IFP ");
1393 			break;
1394 		case RTAX_IFA:
1395 			kprintf("(IFA ");
1396 			break;
1397 		case RTAX_AUTHOR:
1398 			kprintf("(AUT ");
1399 			break;
1400 		case RTAX_BRD:
1401 			kprintf("(BRD ");
1402 			break;
1403 		default:
1404 			kprintf("(?%02d ", i);
1405 			break;
1406 		}
1407 		sockaddr_print(rti->rti_info[i]);
1408 		kprintf(")");
1409 		didit = 1;
1410 	}
1411 	kprintf("\n");
1412 }
1413 
1414 void
1415 sockaddr_print(struct sockaddr *sa)
1416 {
1417 	struct sockaddr_in *sa4;
1418 	struct sockaddr_in6 *sa6;
1419 	int len;
1420 	int i;
1421 
1422 	if (sa == NULL) {
1423 		kprintf("NULL");
1424 		return;
1425 	}
1426 
1427 	len = sa->sa_len - offsetof(struct sockaddr, sa_data[0]);
1428 
1429 	switch(sa->sa_family) {
1430 	case AF_INET:
1431 	case AF_INET6:
1432 	default:
1433 		switch(sa->sa_family) {
1434 		case AF_INET:
1435 			sa4 = (struct sockaddr_in *)sa;
1436 			kprintf("INET %d %d.%d.%d.%d",
1437 				ntohs(sa4->sin_port),
1438 				(ntohl(sa4->sin_addr.s_addr) >> 24) & 255,
1439 				(ntohl(sa4->sin_addr.s_addr) >> 16) & 255,
1440 				(ntohl(sa4->sin_addr.s_addr) >> 8) & 255,
1441 				(ntohl(sa4->sin_addr.s_addr) >> 0) & 255
1442 			);
1443 			break;
1444 		case AF_INET6:
1445 			sa6 = (struct sockaddr_in6 *)sa;
1446 			kprintf("INET6 %d %04x:%04x%04x:%04x:%04x:%04x:%04x:%04x",
1447 				ntohs(sa6->sin6_port),
1448 				sa6->sin6_addr.s6_addr16[0],
1449 				sa6->sin6_addr.s6_addr16[1],
1450 				sa6->sin6_addr.s6_addr16[2],
1451 				sa6->sin6_addr.s6_addr16[3],
1452 				sa6->sin6_addr.s6_addr16[4],
1453 				sa6->sin6_addr.s6_addr16[5],
1454 				sa6->sin6_addr.s6_addr16[6],
1455 				sa6->sin6_addr.s6_addr16[7]
1456 			);
1457 			break;
1458 		default:
1459 			kprintf("AF%d ", sa->sa_family);
1460 			while (len > 0 && sa->sa_data[len-1] == 0)
1461 				--len;
1462 
1463 			for (i = 0; i < len; ++i) {
1464 				if (i)
1465 					kprintf(".");
1466 				kprintf("%d", (unsigned char)sa->sa_data[i]);
1467 			}
1468 			break;
1469 		}
1470 	}
1471 }
1472 
1473 #endif
1474 
1475 /*
1476  * Set up a routing table entry, normally for an interface.
1477  */
1478 int
1479 rtinit(struct ifaddr *ifa, int cmd, int flags)
1480 {
1481 	struct sockaddr *dst, *deldst, *netmask;
1482 	struct mbuf *m = NULL;
1483 	struct radix_node_head *rnh;
1484 	struct radix_node *rn;
1485 	struct rt_addrinfo rtinfo;
1486 	int error;
1487 
1488 	ASSERT_NETISR0;
1489 
1490 	if (flags & RTF_HOST) {
1491 		dst = ifa->ifa_dstaddr;
1492 		netmask = NULL;
1493 	} else {
1494 		dst = ifa->ifa_addr;
1495 		netmask = ifa->ifa_netmask;
1496 	}
1497 	/*
1498 	 * If it's a delete, check that if it exists, it's on the correct
1499 	 * interface or we might scrub a route to another ifa which would
1500 	 * be confusing at best and possibly worse.
1501 	 */
1502 	if (cmd == RTM_DELETE) {
1503 		/*
1504 		 * It's a delete, so it should already exist..
1505 		 * If it's a net, mask off the host bits
1506 		 * (Assuming we have a mask)
1507 		 */
1508 		if (netmask != NULL) {
1509 			m = m_get(M_NOWAIT, MT_SONAME);
1510 			if (m == NULL)
1511 				return (ENOBUFS);
1512 			mbuftrackid(m, 34);
1513 			deldst = mtod(m, struct sockaddr *);
1514 			rt_maskedcopy(dst, deldst, netmask);
1515 			dst = deldst;
1516 		}
1517 		/*
1518 		 * Look up an rtentry that is in the routing tree and
1519 		 * contains the correct info.
1520 		 */
1521 		if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL ||
1522 		    (rn = rnh->rnh_lookup((char *)dst,
1523 					  (char *)netmask, rnh)) == NULL ||
1524 		    ((struct rtentry *)rn)->rt_ifa != ifa ||
1525 		    !sa_equal((struct sockaddr *)rn->rn_key, dst)) {
1526 			if (m != NULL)
1527 				m_free(m);
1528 			return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1529 		}
1530 		/* XXX */
1531 #if 0
1532 		else {
1533 			/*
1534 			 * One would think that as we are deleting, and we know
1535 			 * it doesn't exist, we could just return at this point
1536 			 * with an "ELSE" clause, but apparently not..
1537 			 */
1538 			return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1539 		}
1540 #endif
1541 	}
1542 	/*
1543 	 * Do the actual request
1544 	 */
1545 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
1546 	rtinfo.rti_info[RTAX_DST] = dst;
1547 	rtinfo.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
1548 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
1549 	rtinfo.rti_flags = flags | ifa->ifa_flags;
1550 	rtinfo.rti_ifa = ifa;
1551 	error = rtrequest1_global(cmd, &rtinfo, rtinit_rtrequest_callback, ifa,
1552 	    RTREQ_PRIO_HIGH);
1553 	if (m != NULL)
1554 		m_free(m);
1555 	return (error);
1556 }
1557 
1558 static void
1559 rtinit_rtrequest_callback(int cmd, int error,
1560 			  struct rt_addrinfo *rtinfo, struct rtentry *rt,
1561 			  void *arg)
1562 {
1563 	struct ifaddr *ifa = arg;
1564 
1565 	if (error == 0 && rt) {
1566 		if (mycpuid == 0) {
1567 			++rt->rt_refcnt;
1568 			rt_newaddrmsg(cmd, ifa, error, rt);
1569 			--rt->rt_refcnt;
1570 		}
1571 		if (cmd == RTM_DELETE) {
1572 			if (rt->rt_refcnt == 0) {
1573 				++rt->rt_refcnt;
1574 				rtfree(rt);
1575 			}
1576 		}
1577 	}
1578 }
1579 
1580 struct netmsg_rts {
1581 	struct netmsg_base	base;
1582 	int			req;
1583 	struct rt_addrinfo	*rtinfo;
1584 	rtsearch_callback_func_t callback;
1585 	void			*arg;
1586 	boolean_t		exact_match;
1587 	int			found_cnt;
1588 };
1589 
1590 int
1591 rtsearch_global(int req, struct rt_addrinfo *rtinfo,
1592     rtsearch_callback_func_t callback, void *arg, boolean_t exact_match,
1593     boolean_t req_prio)
1594 {
1595 	struct netmsg_rts msg;
1596 	int flags = 0;
1597 
1598 	if (req_prio)
1599 		flags = MSGF_PRIORITY;
1600 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
1601 	    rtsearch_msghandler);
1602 	msg.req = req;
1603 	msg.rtinfo = rtinfo;
1604 	msg.callback = callback;
1605 	msg.arg = arg;
1606 	msg.exact_match = exact_match;
1607 	msg.found_cnt = 0;
1608 	return (netisr_domsg_global(&msg.base));
1609 }
1610 
1611 static void
1612 rtsearch_msghandler(netmsg_t msg)
1613 {
1614 	struct netmsg_rts *rmsg = (void *)msg;
1615 	struct rt_addrinfo rtinfo;
1616 	struct radix_node_head *rnh;
1617 	struct rtentry *rt;
1618 	int error;
1619 
1620 	ASSERT_NETISR_NCPUS(mycpuid);
1621 
1622 	/*
1623 	 * Copy the rtinfo.  We need to make sure that the original
1624 	 * rtinfo, which is setup by the caller, in the netmsg will
1625 	 * _not_ be changed; else the next CPU on the netmsg forwarding
1626 	 * path will see a different rtinfo than what this CPU has seen.
1627 	 */
1628 	rtinfo = *rmsg->rtinfo;
1629 
1630 	/*
1631 	 * Find the correct routing tree to use for this Address Family
1632 	 */
1633 	if ((rnh = rt_tables[mycpuid][rtinfo.rti_dst->sa_family]) == NULL) {
1634 		if (mycpuid != 0)
1635 			panic("partially initialized routing tables");
1636 		netisr_replymsg(&rmsg->base, EAFNOSUPPORT);
1637 		return;
1638 	}
1639 
1640 	/*
1641 	 * Correct rtinfo for the host route searching.
1642 	 */
1643 	if (rtinfo.rti_flags & RTF_HOST) {
1644 		rtinfo.rti_netmask = NULL;
1645 		rtinfo.rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
1646 	}
1647 
1648 	rt = (struct rtentry *)
1649 	     rnh->rnh_lookup((char *)rtinfo.rti_dst,
1650 			     (char *)rtinfo.rti_netmask, rnh);
1651 
1652 	/*
1653 	 * If we are asked to do the "exact match", we need to make sure
1654 	 * that host route searching got a host route while a network
1655 	 * route searching got a network route.
1656 	 */
1657 	if (rt != NULL && rmsg->exact_match &&
1658 	    ((rt->rt_flags ^ rtinfo.rti_flags) & RTF_HOST))
1659 		rt = NULL;
1660 
1661 	if (rt == NULL) {
1662 		/*
1663 		 * No matching routes have been found, don't count this
1664 		 * as a critical error (here, we set 'error' to 0), just
1665 		 * keep moving on, since at least prcloned routes are not
1666 		 * duplicated onto each CPU.
1667 		 */
1668 		error = 0;
1669 	} else {
1670 		rmsg->found_cnt++;
1671 
1672 		rt->rt_refcnt++;
1673 		error = rmsg->callback(rmsg->req, &rtinfo, rt, rmsg->arg,
1674 				      rmsg->found_cnt);
1675 		rt->rt_refcnt--;
1676 
1677 		if (error == EJUSTRETURN) {
1678 			netisr_replymsg(&rmsg->base, 0);
1679 			return;
1680 		}
1681 	}
1682 
1683 	if (error) {
1684 		KKASSERT(rmsg->found_cnt > 0);
1685 
1686 		/*
1687 		 * Under following cases, unrecoverable error has
1688 		 * not occured:
1689 		 * o  Request is RTM_GET
1690 		 * o  The first time that we find the route, but the
1691 		 *    modification fails.
1692 		 */
1693 		if (rmsg->req != RTM_GET && rmsg->found_cnt > 1) {
1694 			panic("rtsearch_msghandler: unrecoverable error "
1695 			      "cpu %d", mycpuid);
1696 		}
1697 		netisr_replymsg(&rmsg->base, error);
1698 	} else {
1699 		if (rmsg->found_cnt == 0) {
1700 			/* The requested route has not been seen ... */
1701 			error = ESRCH;
1702 		}
1703 		netisr_forwardmsg_error(&rmsg->base, mycpuid + 1, error);
1704 	}
1705 }
1706 
1707 int
1708 rtmask_add_global(struct sockaddr *mask, boolean_t req_prio)
1709 {
1710 	struct netmsg_base msg;
1711 	int flags = 0;
1712 
1713 	if (req_prio)
1714 		flags = MSGF_PRIORITY;
1715 	netmsg_init(&msg, NULL, &curthread->td_msgport, flags,
1716 	    rtmask_add_msghandler);
1717 	msg.lmsg.u.ms_resultp = mask;
1718 
1719 	return (netisr_domsg_global(&msg));
1720 }
1721 
1722 struct sockaddr *
1723 _rtmask_lookup(struct sockaddr *mask, boolean_t search)
1724 {
1725 	struct radix_node *n;
1726 
1727 #define	clen(s)	(*(u_char *)(s))
1728 	n = rn_addmask((char *)mask, search, 1, rn_cpumaskhead(mycpuid));
1729 	if (n != NULL &&
1730 	    mask->sa_len >= clen(n->rn_key) &&
1731 	    bcmp((char *)mask + 1,
1732 		 (char *)n->rn_key + 1, clen(n->rn_key) - 1) == 0) {
1733 		return (struct sockaddr *)n->rn_key;
1734 	} else {
1735 		return NULL;
1736 	}
1737 #undef clen
1738 }
1739 
1740 static void
1741 rtmask_add_msghandler(netmsg_t msg)
1742 {
1743 	struct sockaddr *mask = msg->lmsg.u.ms_resultp;
1744 
1745 	ASSERT_NETISR_NCPUS(mycpuid);
1746 
1747 	if (rtmask_lookup(mask) == NULL) {
1748 		netisr_replymsg(&msg->base, ENOBUFS);
1749 		return;
1750 	}
1751 	netisr_forwardmsg(&msg->base, mycpuid + 1);
1752 }
1753 
1754 /* This must be before ip6_init2(), which is now SI_ORDER_MIDDLE */
1755 SYSINIT(route, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, 0);
1756 
1757 struct rtchange_arg {
1758 	struct ifaddr	*old_ifa;
1759 	struct ifaddr	*new_ifa;
1760 	struct rtentry	*rt;
1761 	int		changed;
1762 };
1763 
1764 static void
1765 rtchange_ifa(struct rtentry *rt, struct rtchange_arg *ap)
1766 {
1767 	if (rt->rt_ifa->ifa_rtrequest != NULL)
1768 		rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt);
1769 	IFAFREE(rt->rt_ifa);
1770 
1771 	IFAREF(ap->new_ifa);
1772 	rt->rt_ifa = ap->new_ifa;
1773 	rt->rt_ifp = ap->new_ifa->ifa_ifp;
1774 	if (rt->rt_ifa->ifa_rtrequest != NULL)
1775 		rt->rt_ifa->ifa_rtrequest(RTM_ADD, rt);
1776 
1777 	ap->changed = 1;
1778 }
1779 
1780 static int
1781 rtchange_callback(struct radix_node *rn, void *xap)
1782 {
1783 	struct rtchange_arg *ap = xap;
1784 	struct rtentry *rt = (struct rtentry *)rn;
1785 
1786 	if (rt->rt_ifa == ap->old_ifa) {
1787 		if (rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) {
1788 			/*
1789 			 * We could saw the branch off when we are
1790 			 * still sitting on it, if the ifa_rtrequest
1791 			 * DEL/ADD are called directly from here.
1792 			 */
1793 			ap->rt = rt;
1794 			return EJUSTRETURN;
1795 		}
1796 		rtchange_ifa(rt, ap);
1797 	}
1798 	return 0;
1799 }
1800 
1801 struct netmsg_rtchange {
1802 	struct netmsg_base	base;
1803 	struct ifaddr		*old_ifa;
1804 	struct ifaddr		*new_ifa;
1805 	int			changed;
1806 };
1807 
1808 static void
1809 rtchange_dispatch(netmsg_t msg)
1810 {
1811 	struct netmsg_rtchange *rmsg = (void *)msg;
1812 	struct radix_node_head *rnh;
1813 	struct rtchange_arg arg;
1814 	int cpu;
1815 
1816 	cpu = mycpuid;
1817 	ASSERT_NETISR_NCPUS(cpu);
1818 
1819 	memset(&arg, 0, sizeof(arg));
1820 	arg.old_ifa = rmsg->old_ifa;
1821 	arg.new_ifa = rmsg->new_ifa;
1822 
1823 	rnh = rt_tables[cpu][AF_INET];
1824 	for (;;) {
1825 		int error;
1826 
1827 		KKASSERT(arg.rt == NULL);
1828 		error = rnh->rnh_walktree(rnh, rtchange_callback, &arg);
1829 		if (arg.rt != NULL) {
1830 			struct rtentry *rt;
1831 
1832 			rt = arg.rt;
1833 			arg.rt = NULL;
1834 			rtchange_ifa(rt, &arg);
1835 		} else {
1836 			break;
1837 		}
1838 	}
1839 	if (arg.changed)
1840 		rmsg->changed = 1;
1841 
1842 	netisr_forwardmsg(&rmsg->base, cpu + 1);
1843 }
1844 
1845 int
1846 rtchange(struct ifaddr *old_ifa, struct ifaddr *new_ifa)
1847 {
1848 	struct netmsg_rtchange msg;
1849 
1850 	/*
1851 	 * XXX individual requests are not independantly chained,
1852 	 * which means that the per-cpu route tables will not be
1853 	 * consistent in the middle of the operation.  If routes
1854 	 * related to the interface are manipulated while we are
1855 	 * doing this the inconsistancy could trigger a panic.
1856 	 */
1857 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, MSGF_PRIORITY,
1858 	    rtchange_dispatch);
1859 	msg.old_ifa = old_ifa;
1860 	msg.new_ifa = new_ifa;
1861 	msg.changed = 0;
1862 	netisr_domsg_global(&msg.base);
1863 
1864 	if (msg.changed) {
1865 		old_ifa->ifa_flags &= ~IFA_ROUTE;
1866 		new_ifa->ifa_flags |= IFA_ROUTE;
1867 		return 0;
1868 	} else {
1869 		return ENOENT;
1870 	}
1871 }
1872