xref: /dragonfly/sys/net/route.c (revision 684cb317)
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];
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 int route_assert_owner_access = 1;
122 SYSCTL_INT(_net_route, OID_AUTO, assert_owner_access, CTLFLAG_RW,
123            &route_assert_owner_access, 0, "");
124 
125 u_long route_kmalloc_limit = 0;
126 TUNABLE_ULONG("net.route.kmalloc_limit", &route_kmalloc_limit);
127 
128 /*
129  * Initialize the route table(s) for protocol domains and
130  * create a helper thread which will be responsible for updating
131  * route table entries on each cpu.
132  */
133 void
134 route_init(void)
135 {
136 	int cpu;
137 
138 	for (cpu = 0; cpu < 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 	if (route_kmalloc_limit)
144 		kmalloc_raise_limit(M_RTABLE, route_kmalloc_limit);
145 }
146 
147 static void
148 rtable_init_oncpu(netmsg_t msg)
149 {
150 	struct domain *dom;
151 	int cpu = mycpuid;
152 
153 	SLIST_FOREACH(dom, &domains, dom_next) {
154 		if (dom->dom_rtattach) {
155 			dom->dom_rtattach(
156 				(void **)&rt_tables[cpu][dom->dom_family],
157 			        dom->dom_rtoffset);
158 		}
159 	}
160 	ifnet_forwardmsg(&msg->lmsg, cpu + 1);
161 }
162 
163 static void
164 rtable_init(void)
165 {
166 	struct netmsg_base msg;
167 
168 	netmsg_init(&msg, NULL, &curthread->td_msgport, 0, rtable_init_oncpu);
169 	ifnet_domsg(&msg.lmsg, 0);
170 }
171 
172 /*
173  * Routing statistics.
174  */
175 static int
176 sysctl_rtstatistics(SYSCTL_HANDLER_ARGS)
177 {
178 	int cpu, error = 0;
179 
180 	for (cpu = 0; cpu < ncpus; ++cpu) {
181 		if ((error = SYSCTL_OUT(req, &rtstatistics_percpu[cpu],
182 					sizeof(struct rtstatistics))))
183 				break;
184 		if ((error = SYSCTL_IN(req, &rtstatistics_percpu[cpu],
185 					sizeof(struct rtstatistics))))
186 				break;
187 	}
188 
189 	return (error);
190 }
191 SYSCTL_PROC(_net_route, OID_AUTO, stats, (CTLTYPE_OPAQUE|CTLFLAG_RW),
192 	0, 0, sysctl_rtstatistics, "S,rtstatistics", "Routing statistics");
193 
194 /*
195  * Packet routing routines.
196  */
197 
198 /*
199  * Look up and fill in the "ro_rt" rtentry field in a route structure given
200  * an address in the "ro_dst" field.  Always send a report on a miss and
201  * always clone routes.
202  */
203 void
204 rtalloc(struct route *ro)
205 {
206 	rtalloc_ign(ro, 0UL);
207 }
208 
209 /*
210  * Look up and fill in the "ro_rt" rtentry field in a route structure given
211  * an address in the "ro_dst" field.  Always send a report on a miss and
212  * optionally clone routes when RTF_CLONING or RTF_PRCLONING are not being
213  * ignored.
214  */
215 void
216 rtalloc_ign(struct route *ro, u_long ignoreflags)
217 {
218 	if (ro->ro_rt != NULL) {
219 		if (ro->ro_rt->rt_ifp != NULL && ro->ro_rt->rt_flags & RTF_UP)
220 			return;
221 		rtfree(ro->ro_rt);
222 		ro->ro_rt = NULL;
223 	}
224 	ro->ro_rt = _rtlookup(&ro->ro_dst, RTL_REPORTMSG, ignoreflags);
225 }
226 
227 /*
228  * Look up the route that matches the given "dst" address.
229  *
230  * Route lookup can have the side-effect of creating and returning
231  * a cloned route instead when "dst" matches a cloning route and the
232  * RTF_CLONING and RTF_PRCLONING flags are not being ignored.
233  *
234  * Any route returned has its reference count incremented.
235  */
236 struct rtentry *
237 _rtlookup(struct sockaddr *dst, boolean_t generate_report, u_long ignore)
238 {
239 	struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
240 	struct rtentry *rt;
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 	if (rt->rt_cpuid == mycpuid)
295 		rtfree_oncpu(rt);
296 	else
297 		rtfree_remote(rt);
298 }
299 
300 void
301 rtfree_oncpu(struct rtentry *rt)
302 {
303 	KKASSERT(rt->rt_cpuid == mycpuid);
304 	KASSERT(rt->rt_refcnt > 0, ("rtfree: rt_refcnt %ld", rt->rt_refcnt));
305 
306 	--rt->rt_refcnt;
307 	if (rt->rt_refcnt == 0) {
308 		struct radix_node_head *rnh =
309 		    rt_tables[mycpuid][rt_key(rt)->sa_family];
310 
311 		if (rnh->rnh_close)
312 			rnh->rnh_close((struct radix_node *)rt, rnh);
313 		if (!(rt->rt_flags & RTF_UP)) {
314 			/* deallocate route */
315 			if (rt->rt_ifa != NULL)
316 				IFAFREE(rt->rt_ifa);
317 			if (rt->rt_parent != NULL)
318 				RTFREE(rt->rt_parent);	/* recursive call! */
319 			Free(rt_key(rt));
320 			Free(rt);
321 		}
322 	}
323 }
324 
325 static void
326 rtfree_remote_dispatch(netmsg_t msg)
327 {
328 	struct lwkt_msg *lmsg = &msg->lmsg;
329 	struct rtentry *rt = lmsg->u.ms_resultp;
330 
331 	rtfree_oncpu(rt);
332 	lwkt_replymsg(lmsg, 0);
333 }
334 
335 void
336 rtfree_remote(struct rtentry *rt)
337 {
338 	struct netmsg_base *msg;
339 	struct lwkt_msg *lmsg;
340 
341 	KKASSERT(rt->rt_cpuid != mycpuid);
342 
343 	if (route_assert_owner_access) {
344 		panic("rt remote free rt_cpuid %d, mycpuid %d",
345 		      rt->rt_cpuid, mycpuid);
346 	} else {
347 		kprintf("rt remote free rt_cpuid %d, mycpuid %d\n",
348 			rt->rt_cpuid, mycpuid);
349 		print_backtrace(-1);
350 	}
351 
352 	msg = kmalloc(sizeof(*msg), M_LWKTMSG, M_INTWAIT);
353 	netmsg_init(msg, NULL, &netisr_afree_rport, 0, rtfree_remote_dispatch);
354 	lmsg = &msg->lmsg;
355 	lmsg->u.ms_resultp = rt;
356 
357 	lwkt_sendmsg(netisr_cpuport(rt->rt_cpuid), lmsg);
358 }
359 
360 static int
361 rtredirect_oncpu(struct sockaddr *dst, struct sockaddr *gateway,
362 		 struct sockaddr *netmask, int flags, struct sockaddr *src)
363 {
364 	struct rtentry *rt = NULL;
365 	struct rt_addrinfo rtinfo;
366 	struct ifaddr *ifa;
367 	u_long *stat = NULL;
368 	int error;
369 
370 	/* verify the gateway is directly reachable */
371 	if ((ifa = ifa_ifwithnet(gateway)) == NULL) {
372 		error = ENETUNREACH;
373 		goto out;
374 	}
375 
376 	/*
377 	 * If the redirect isn't from our current router for this destination,
378 	 * it's either old or wrong.
379 	 */
380 	if (!(flags & RTF_DONE) &&		/* XXX JH */
381 	    (rt = rtpurelookup(dst)) != NULL &&
382 	    (!sa_equal(src, rt->rt_gateway) || rt->rt_ifa != ifa)) {
383 		error = EINVAL;
384 		goto done;
385 	}
386 
387 	/*
388 	 * If it redirects us to ourselves, we have a routing loop,
389 	 * perhaps as a result of an interface going down recently.
390 	 */
391 	if (ifa_ifwithaddr(gateway)) {
392 		error = EHOSTUNREACH;
393 		goto done;
394 	}
395 
396 	/*
397 	 * Create a new entry if the lookup failed or if we got back
398 	 * a wildcard entry for the default route.  This is necessary
399 	 * for hosts which use routing redirects generated by smart
400 	 * gateways to dynamically build the routing tables.
401 	 */
402 	if (rt == NULL)
403 		goto create;
404 	if ((rt_mask(rt) != NULL && rt_mask(rt)->sa_len < 2)) {
405 		rtfree(rt);
406 		goto create;
407 	}
408 
409 	/* Ignore redirects for directly connected hosts. */
410 	if (!(rt->rt_flags & RTF_GATEWAY)) {
411 		error = EHOSTUNREACH;
412 		goto done;
413 	}
414 
415 	if (!(rt->rt_flags & RTF_HOST) && (flags & RTF_HOST)) {
416 		/*
417 		 * Changing from a network route to a host route.
418 		 * Create a new host route rather than smashing the
419 		 * network route.
420 		 */
421 create:
422 		flags |=  RTF_GATEWAY | RTF_DYNAMIC;
423 		bzero(&rtinfo, sizeof(struct rt_addrinfo));
424 		rtinfo.rti_info[RTAX_DST] = dst;
425 		rtinfo.rti_info[RTAX_GATEWAY] = gateway;
426 		rtinfo.rti_info[RTAX_NETMASK] = netmask;
427 		rtinfo.rti_flags = flags;
428 		rtinfo.rti_ifa = ifa;
429 		rt = NULL;	/* copy-in/copy-out parameter */
430 		error = rtrequest1(RTM_ADD, &rtinfo, &rt);
431 		if (rt != NULL)
432 			flags = rt->rt_flags;
433 		stat = &rtstat.rts_dynamic;
434 	} else {
435 		/*
436 		 * Smash the current notion of the gateway to this destination.
437 		 * Should check about netmask!!!
438 		 */
439 		rt->rt_flags |= RTF_MODIFIED;
440 		flags |= RTF_MODIFIED;
441 
442 		/* We only need to report rtmsg on CPU0 */
443 		rt_setgate(rt, rt_key(rt), gateway,
444 			   mycpuid == 0 ? RTL_REPORTMSG : RTL_DONTREPORT);
445 		error = 0;
446 		stat = &rtstat.rts_newgateway;
447 	}
448 
449 done:
450 	if (rt != NULL)
451 		rtfree(rt);
452 out:
453 	if (error != 0)
454 		rtstat.rts_badredirect++;
455 	else if (stat != NULL)
456 		(*stat)++;
457 
458 	return error;
459 }
460 
461 struct netmsg_rtredirect {
462 	struct netmsg_base base;
463 	struct sockaddr *dst;
464 	struct sockaddr *gateway;
465 	struct sockaddr *netmask;
466 	int		flags;
467 	struct sockaddr *src;
468 };
469 
470 /*
471  * Force a routing table entry to the specified
472  * destination to go through the given gateway.
473  * Normally called as a result of a routing redirect
474  * message from the network layer.
475  *
476  * N.B.: must be called at splnet
477  */
478 void
479 rtredirect(struct sockaddr *dst, struct sockaddr *gateway,
480 	   struct sockaddr *netmask, int flags, struct sockaddr *src)
481 {
482 	struct rt_addrinfo rtinfo;
483 	int error;
484 	struct netmsg_rtredirect msg;
485 
486 	netmsg_init(&msg.base, NULL, &curthread->td_msgport,
487 		    0, rtredirect_msghandler);
488 	msg.dst = dst;
489 	msg.gateway = gateway;
490 	msg.netmask = netmask;
491 	msg.flags = flags;
492 	msg.src = src;
493 	error = rt_domsg_global(&msg.base);
494 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
495 	rtinfo.rti_info[RTAX_DST] = dst;
496 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
497 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
498 	rtinfo.rti_info[RTAX_AUTHOR] = src;
499 	rt_missmsg(RTM_REDIRECT, &rtinfo, flags, error);
500 }
501 
502 static void
503 rtredirect_msghandler(netmsg_t msg)
504 {
505 	struct netmsg_rtredirect *rmsg = (void *)msg;
506 	int nextcpu;
507 
508 	rtredirect_oncpu(rmsg->dst, rmsg->gateway, rmsg->netmask,
509 			 rmsg->flags, rmsg->src);
510 	nextcpu = mycpuid + 1;
511 	if (nextcpu < ncpus)
512 		lwkt_forwardmsg(netisr_cpuport(nextcpu), &msg->lmsg);
513 	else
514 		lwkt_replymsg(&msg->lmsg, 0);
515 }
516 
517 /*
518 * Routing table ioctl interface.
519 */
520 int
521 rtioctl(u_long req, caddr_t data, struct ucred *cred)
522 {
523 #ifdef INET
524 	/* Multicast goop, grrr... */
525 	return mrt_ioctl ? mrt_ioctl(req, data) : EOPNOTSUPP;
526 #else
527 	return ENXIO;
528 #endif
529 }
530 
531 struct ifaddr *
532 ifa_ifwithroute(int flags, struct sockaddr *dst, struct sockaddr *gateway)
533 {
534 	struct ifaddr *ifa;
535 
536 	if (!(flags & RTF_GATEWAY)) {
537 		/*
538 		 * If we are adding a route to an interface,
539 		 * and the interface is a point-to-point link,
540 		 * we should search for the destination
541 		 * as our clue to the interface.  Otherwise
542 		 * we can use the local address.
543 		 */
544 		ifa = NULL;
545 		if (flags & RTF_HOST) {
546 			ifa = ifa_ifwithdstaddr(dst);
547 		}
548 		if (ifa == NULL)
549 			ifa = ifa_ifwithaddr(gateway);
550 	} else {
551 		/*
552 		 * If we are adding a route to a remote net
553 		 * or host, the gateway may still be on the
554 		 * other end of a pt to pt link.
555 		 */
556 		ifa = ifa_ifwithdstaddr(gateway);
557 	}
558 	if (ifa == NULL)
559 		ifa = ifa_ifwithnet(gateway);
560 	if (ifa == NULL) {
561 		struct rtentry *rt;
562 
563 		rt = rtpurelookup(gateway);
564 		if (rt == NULL)
565 			return (NULL);
566 		rt->rt_refcnt--;
567 		if ((ifa = rt->rt_ifa) == NULL)
568 			return (NULL);
569 	}
570 	if (ifa->ifa_addr->sa_family != dst->sa_family) {
571 		struct ifaddr *oldifa = ifa;
572 
573 		ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
574 		if (ifa == NULL)
575 			ifa = oldifa;
576 	}
577 	return (ifa);
578 }
579 
580 static int rt_fixdelete (struct radix_node *, void *);
581 static int rt_fixchange (struct radix_node *, void *);
582 
583 struct rtfc_arg {
584 	struct rtentry *rt0;
585 	struct radix_node_head *rnh;
586 };
587 
588 /*
589  * Set rtinfo->rti_ifa and rtinfo->rti_ifp.
590  */
591 int
592 rt_getifa(struct rt_addrinfo *rtinfo)
593 {
594 	struct sockaddr *gateway = rtinfo->rti_info[RTAX_GATEWAY];
595 	struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
596 	struct sockaddr *ifaaddr = rtinfo->rti_info[RTAX_IFA];
597 	int flags = rtinfo->rti_flags;
598 
599 	/*
600 	 * ifp may be specified by sockaddr_dl
601 	 * when protocol address is ambiguous.
602 	 */
603 	if (rtinfo->rti_ifp == NULL) {
604 		struct sockaddr *ifpaddr;
605 
606 		ifpaddr = rtinfo->rti_info[RTAX_IFP];
607 		if (ifpaddr != NULL && ifpaddr->sa_family == AF_LINK) {
608 			struct ifaddr *ifa;
609 
610 			ifa = ifa_ifwithnet(ifpaddr);
611 			if (ifa != NULL)
612 				rtinfo->rti_ifp = ifa->ifa_ifp;
613 		}
614 	}
615 
616 	if (rtinfo->rti_ifa == NULL && ifaaddr != NULL)
617 		rtinfo->rti_ifa = ifa_ifwithaddr(ifaaddr);
618 	if (rtinfo->rti_ifa == NULL) {
619 		struct sockaddr *sa;
620 
621 		sa = ifaaddr != NULL ? ifaaddr :
622 		    (gateway != NULL ? gateway : dst);
623 		if (sa != NULL && rtinfo->rti_ifp != NULL)
624 			rtinfo->rti_ifa = ifaof_ifpforaddr(sa, rtinfo->rti_ifp);
625 		else if (dst != NULL && gateway != NULL)
626 			rtinfo->rti_ifa = ifa_ifwithroute(flags, dst, gateway);
627 		else if (sa != NULL)
628 			rtinfo->rti_ifa = ifa_ifwithroute(flags, sa, sa);
629 	}
630 	if (rtinfo->rti_ifa == NULL)
631 		return (ENETUNREACH);
632 
633 	if (rtinfo->rti_ifp == NULL)
634 		rtinfo->rti_ifp = rtinfo->rti_ifa->ifa_ifp;
635 	return (0);
636 }
637 
638 /*
639  * Do appropriate manipulations of a routing tree given
640  * all the bits of info needed
641  */
642 int
643 rtrequest(
644 	int req,
645 	struct sockaddr *dst,
646 	struct sockaddr *gateway,
647 	struct sockaddr *netmask,
648 	int flags,
649 	struct rtentry **ret_nrt)
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(req, &rtinfo, ret_nrt);
659 }
660 
661 int
662 rtrequest_global(
663 	int req,
664 	struct sockaddr *dst,
665 	struct sockaddr *gateway,
666 	struct sockaddr *netmask,
667 	int flags)
668 {
669 	struct rt_addrinfo rtinfo;
670 
671 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
672 	rtinfo.rti_info[RTAX_DST] = dst;
673 	rtinfo.rti_info[RTAX_GATEWAY] = gateway;
674 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
675 	rtinfo.rti_flags = flags;
676 	return rtrequest1_global(req, &rtinfo, NULL, NULL, RTREQ_PRIO_NORM);
677 }
678 
679 struct netmsg_rtq {
680 	struct netmsg_base	base;
681 	int			req;
682 	struct rt_addrinfo	*rtinfo;
683 	rtrequest1_callback_func_t callback;
684 	void			*arg;
685 };
686 
687 int
688 rtrequest1_global(int req, struct rt_addrinfo *rtinfo,
689     rtrequest1_callback_func_t callback, void *arg, boolean_t req_prio)
690 {
691 	int error, flags = 0;
692 	struct netmsg_rtq msg;
693 
694 	if (req_prio)
695 		flags = MSGF_PRIORITY;
696 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
697 	    rtrequest1_msghandler);
698 	msg.base.lmsg.ms_error = -1;
699 	msg.req = req;
700 	msg.rtinfo = rtinfo;
701 	msg.callback = callback;
702 	msg.arg = arg;
703 	error = rt_domsg_global(&msg.base);
704 	return (error);
705 }
706 
707 /*
708  * Handle a route table request on the current cpu.  Since the route table's
709  * are supposed to be identical on each cpu, an error occuring later in the
710  * message chain is considered system-fatal.
711  */
712 static void
713 rtrequest1_msghandler(netmsg_t msg)
714 {
715 	struct netmsg_rtq *rmsg = (void *)msg;
716 	struct rt_addrinfo rtinfo;
717 	struct rtentry *rt = NULL;
718 	int nextcpu;
719 	int error;
720 
721 	/*
722 	 * Copy the rtinfo.  We need to make sure that the original
723 	 * rtinfo, which is setup by the caller, in the netmsg will
724 	 * _not_ be changed; else the next CPU on the netmsg forwarding
725 	 * path will see a different rtinfo than what this CPU has seen.
726 	 */
727 	rtinfo = *rmsg->rtinfo;
728 
729 	error = rtrequest1(rmsg->req, &rtinfo, &rt);
730 	if (rt)
731 		--rt->rt_refcnt;
732 	if (rmsg->callback)
733 		rmsg->callback(rmsg->req, error, &rtinfo, rt, rmsg->arg);
734 
735 	/*
736 	 * RTM_DELETE's are propogated even if an error occurs, since a
737 	 * cloned route might be undergoing deletion and cloned routes
738 	 * are not necessarily replicated.  An overall error is returned
739 	 * only if no cpus have the route in question.
740 	 */
741 	if (rmsg->base.lmsg.ms_error < 0 || error == 0)
742 		rmsg->base.lmsg.ms_error = error;
743 
744 	nextcpu = mycpuid + 1;
745 	if (error && rmsg->req != RTM_DELETE) {
746 		if (mycpuid != 0) {
747 			panic("rtrequest1_msghandler: rtrequest table "
748 			      "error was cpu%d, err %d\n", mycpuid, error);
749 		}
750 		lwkt_replymsg(&rmsg->base.lmsg, error);
751 	} else if (nextcpu < ncpus) {
752 		lwkt_forwardmsg(netisr_cpuport(nextcpu), &rmsg->base.lmsg);
753 	} else {
754 		lwkt_replymsg(&rmsg->base.lmsg, rmsg->base.lmsg.ms_error);
755 	}
756 }
757 
758 int
759 rtrequest1(int req, struct rt_addrinfo *rtinfo, struct rtentry **ret_nrt)
760 {
761 	struct sockaddr *dst = rtinfo->rti_info[RTAX_DST];
762 	struct rtentry *rt;
763 	struct radix_node *rn;
764 	struct radix_node_head *rnh;
765 	struct ifaddr *ifa;
766 	struct sockaddr *ndst;
767 	boolean_t reportmsg;
768 	int error = 0;
769 
770 #define gotoerr(x) { error = x ; goto bad; }
771 
772 #ifdef ROUTE_DEBUG
773 	if (route_debug)
774 		rt_addrinfo_print(req, rtinfo);
775 #endif
776 
777 	crit_enter();
778 	/*
779 	 * Find the correct routing tree to use for this Address Family
780 	 */
781 	if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL)
782 		gotoerr(EAFNOSUPPORT);
783 
784 	/*
785 	 * If we are adding a host route then we don't want to put
786 	 * a netmask in the tree, nor do we want to clone it.
787 	 */
788 	if (rtinfo->rti_flags & RTF_HOST) {
789 		rtinfo->rti_info[RTAX_NETMASK] = NULL;
790 		rtinfo->rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
791 	}
792 
793 	switch (req) {
794 	case RTM_DELETE:
795 		/* Remove the item from the tree. */
796 		rn = rnh->rnh_deladdr((char *)rtinfo->rti_info[RTAX_DST],
797 				      (char *)rtinfo->rti_info[RTAX_NETMASK],
798 				      rnh);
799 		if (rn == NULL)
800 			gotoerr(ESRCH);
801 		KASSERT(!(rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)),
802 			("rnh_deladdr returned flags 0x%x", rn->rn_flags));
803 		rt = (struct rtentry *)rn;
804 
805 		/* ref to prevent a deletion race */
806 		++rt->rt_refcnt;
807 
808 		/* Free any routes cloned from this one. */
809 		if ((rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) &&
810 		    rt_mask(rt) != NULL) {
811 			rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
812 					       (char *)rt_mask(rt),
813 					       rt_fixdelete, rt);
814 		}
815 
816 		if (rt->rt_gwroute != NULL) {
817 			RTFREE(rt->rt_gwroute);
818 			rt->rt_gwroute = NULL;
819 		}
820 
821 		/*
822 		 * NB: RTF_UP must be set during the search above,
823 		 * because we might delete the last ref, causing
824 		 * rt to get freed prematurely.
825 		 */
826 		rt->rt_flags &= ~RTF_UP;
827 
828 #ifdef ROUTE_DEBUG
829 		if (route_debug)
830 			rt_print(rtinfo, rt);
831 #endif
832 
833 		/* Give the protocol a chance to keep things in sync. */
834 		if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
835 			ifa->ifa_rtrequest(RTM_DELETE, rt);
836 
837 		/*
838 		 * If the caller wants it, then it can have it,
839 		 * but it's up to it to free the rtentry as we won't be
840 		 * doing it.
841 		 */
842 		KASSERT(rt->rt_refcnt >= 0,
843 			("rtrequest1(DELETE): refcnt %ld", rt->rt_refcnt));
844 		if (ret_nrt != NULL) {
845 			/* leave ref intact for return */
846 			*ret_nrt = rt;
847 		} else {
848 			/* deref / attempt to destroy */
849 			rtfree(rt);
850 		}
851 		break;
852 
853 	case RTM_RESOLVE:
854 		if (ret_nrt == NULL || (rt = *ret_nrt) == NULL)
855 			gotoerr(EINVAL);
856 
857 		KASSERT(rt->rt_cpuid == mycpuid,
858 		    ("rt resolve rt_cpuid %d, mycpuid %d",
859 		     rt->rt_cpuid, mycpuid));
860 
861 		ifa = rt->rt_ifa;
862 		rtinfo->rti_flags =
863 		    rt->rt_flags & ~(RTF_CLONING | RTF_PRCLONING | RTF_STATIC);
864 		rtinfo->rti_flags |= RTF_WASCLONED;
865 		rtinfo->rti_info[RTAX_GATEWAY] = rt->rt_gateway;
866 		if ((rtinfo->rti_info[RTAX_NETMASK] = rt->rt_genmask) == NULL)
867 			rtinfo->rti_flags |= RTF_HOST;
868 		rtinfo->rti_info[RTAX_MPLS1] = rt->rt_shim[0];
869 		rtinfo->rti_info[RTAX_MPLS2] = rt->rt_shim[1];
870 		rtinfo->rti_info[RTAX_MPLS3] = rt->rt_shim[2];
871 		goto makeroute;
872 
873 	case RTM_ADD:
874 		KASSERT(!(rtinfo->rti_flags & RTF_GATEWAY) ||
875 			rtinfo->rti_info[RTAX_GATEWAY] != NULL,
876 		    ("rtrequest: GATEWAY but no gateway"));
877 
878 		if (rtinfo->rti_ifa == NULL && (error = rt_getifa(rtinfo)))
879 			gotoerr(error);
880 		ifa = rtinfo->rti_ifa;
881 makeroute:
882 		R_Malloc(rt, struct rtentry *, sizeof(struct rtentry));
883 		if (rt == NULL) {
884 			if (req == RTM_ADD) {
885 				kprintf("rtrequest1: alloc rtentry failed on "
886 				    "cpu%d\n", mycpuid);
887 			}
888 			gotoerr(ENOBUFS);
889 		}
890 		bzero(rt, sizeof(struct rtentry));
891 		rt->rt_flags = RTF_UP | rtinfo->rti_flags;
892 		rt->rt_cpuid = mycpuid;
893 
894 		if (mycpuid != 0 && req == RTM_ADD) {
895 			/* For RTM_ADD, we have already sent rtmsg on CPU0. */
896 			reportmsg = RTL_DONTREPORT;
897 		} else {
898 			/*
899 			 * For RTM_ADD, we only send rtmsg on CPU0.
900 			 * For RTM_RESOLVE, we always send rtmsg. XXX
901 			 */
902 			reportmsg = RTL_REPORTMSG;
903 		}
904 		error = rt_setgate(rt, dst, rtinfo->rti_info[RTAX_GATEWAY],
905 				   reportmsg);
906 		if (error != 0) {
907 			Free(rt);
908 			gotoerr(error);
909 		}
910 
911 		ndst = rt_key(rt);
912 		if (rtinfo->rti_info[RTAX_NETMASK] != NULL)
913 			rt_maskedcopy(dst, ndst,
914 				      rtinfo->rti_info[RTAX_NETMASK]);
915 		else
916 			bcopy(dst, ndst, dst->sa_len);
917 
918 		if (rtinfo->rti_info[RTAX_MPLS1] != NULL)
919 			rt_setshims(rt, rtinfo->rti_info);
920 
921 		/*
922 		 * Note that we now have a reference to the ifa.
923 		 * This moved from below so that rnh->rnh_addaddr() can
924 		 * examine the ifa and  ifa->ifa_ifp if it so desires.
925 		 */
926 		IFAREF(ifa);
927 		rt->rt_ifa = ifa;
928 		rt->rt_ifp = ifa->ifa_ifp;
929 		/* XXX mtu manipulation will be done in rnh_addaddr -- itojun */
930 
931 		rn = rnh->rnh_addaddr((char *)ndst,
932 				      (char *)rtinfo->rti_info[RTAX_NETMASK],
933 				      rnh, rt->rt_nodes);
934 		if (rn == NULL) {
935 			struct rtentry *oldrt;
936 
937 			/*
938 			 * We already have one of these in the tree.
939 			 * We do a special hack: if the old route was
940 			 * cloned, then we blow it away and try
941 			 * re-inserting the new one.
942 			 */
943 			oldrt = rtpurelookup(ndst);
944 			if (oldrt != NULL) {
945 				--oldrt->rt_refcnt;
946 				if (oldrt->rt_flags & RTF_WASCLONED) {
947 					rtrequest(RTM_DELETE, rt_key(oldrt),
948 						  oldrt->rt_gateway,
949 						  rt_mask(oldrt),
950 						  oldrt->rt_flags, NULL);
951 					rn = rnh->rnh_addaddr((char *)ndst,
952 					    (char *)
953 						rtinfo->rti_info[RTAX_NETMASK],
954 					    rnh, rt->rt_nodes);
955 				}
956 			}
957 		}
958 
959 		/*
960 		 * If it still failed to go into the tree,
961 		 * then un-make it (this should be a function).
962 		 */
963 		if (rn == NULL) {
964 			if (rt->rt_gwroute != NULL)
965 				rtfree(rt->rt_gwroute);
966 			IFAFREE(ifa);
967 			Free(rt_key(rt));
968 			Free(rt);
969 			gotoerr(EEXIST);
970 		}
971 
972 		/*
973 		 * If we got here from RESOLVE, then we are cloning
974 		 * so clone the rest, and note that we
975 		 * are a clone (and increment the parent's references)
976 		 */
977 		if (req == RTM_RESOLVE) {
978 			rt->rt_rmx = (*ret_nrt)->rt_rmx;    /* copy metrics */
979 			rt->rt_rmx.rmx_pksent = 0;  /* reset packet counter */
980 			if ((*ret_nrt)->rt_flags &
981 				       (RTF_CLONING | RTF_PRCLONING)) {
982 				rt->rt_parent = *ret_nrt;
983 				(*ret_nrt)->rt_refcnt++;
984 			}
985 		}
986 
987 		/*
988 		 * if this protocol has something to add to this then
989 		 * allow it to do that as well.
990 		 */
991 		if (ifa->ifa_rtrequest != NULL)
992 			ifa->ifa_rtrequest(req, rt);
993 
994 		/*
995 		 * We repeat the same procedure from rt_setgate() here because
996 		 * it doesn't fire when we call it there because the node
997 		 * hasn't been added to the tree yet.
998 		 */
999 		if (req == RTM_ADD && !(rt->rt_flags & RTF_HOST) &&
1000 		    rt_mask(rt) != NULL) {
1001 			struct rtfc_arg arg = { rt, rnh };
1002 
1003 			rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
1004 					       (char *)rt_mask(rt),
1005 					       rt_fixchange, &arg);
1006 		}
1007 
1008 #ifdef ROUTE_DEBUG
1009 		if (route_debug)
1010 			rt_print(rtinfo, rt);
1011 #endif
1012 		/*
1013 		 * Return the resulting rtentry,
1014 		 * increasing the number of references by one.
1015 		 */
1016 		if (ret_nrt != NULL) {
1017 			rt->rt_refcnt++;
1018 			*ret_nrt = rt;
1019 		}
1020 		break;
1021 	default:
1022 		error = EOPNOTSUPP;
1023 	}
1024 bad:
1025 #ifdef ROUTE_DEBUG
1026 	if (route_debug) {
1027 		if (error)
1028 			kprintf("rti %p failed error %d\n", rtinfo, error);
1029 		else
1030 			kprintf("rti %p succeeded\n", rtinfo);
1031 	}
1032 #endif
1033 	crit_exit();
1034 	return (error);
1035 }
1036 
1037 /*
1038  * Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family''
1039  * (i.e., the routes related to it by the operation of cloning).  This
1040  * routine is iterated over all potential former-child-routes by way of
1041  * rnh->rnh_walktree_from() above, and those that actually are children of
1042  * the late parent (passed in as VP here) are themselves deleted.
1043  */
1044 static int
1045 rt_fixdelete(struct radix_node *rn, void *vp)
1046 {
1047 	struct rtentry *rt = (struct rtentry *)rn;
1048 	struct rtentry *rt0 = vp;
1049 
1050 	if (rt->rt_parent == rt0 &&
1051 	    !(rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1052 		return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1053 				 rt->rt_flags, NULL);
1054 	}
1055 	return 0;
1056 }
1057 
1058 /*
1059  * This routine is called from rt_setgate() to do the analogous thing for
1060  * adds and changes.  There is the added complication in this case of a
1061  * middle insert; i.e., insertion of a new network route between an older
1062  * network route and (cloned) host routes.  For this reason, a simple check
1063  * of rt->rt_parent is insufficient; each candidate route must be tested
1064  * against the (mask, value) of the new route (passed as before in vp)
1065  * to see if the new route matches it.
1066  *
1067  * XXX - it may be possible to do fixdelete() for changes and reserve this
1068  * routine just for adds.  I'm not sure why I thought it was necessary to do
1069  * changes this way.
1070  */
1071 #ifdef DEBUG
1072 static int rtfcdebug = 0;
1073 #endif
1074 
1075 static int
1076 rt_fixchange(struct radix_node *rn, void *vp)
1077 {
1078 	struct rtentry *rt = (struct rtentry *)rn;
1079 	struct rtfc_arg *ap = vp;
1080 	struct rtentry *rt0 = ap->rt0;
1081 	struct radix_node_head *rnh = ap->rnh;
1082 	u_char *xk1, *xm1, *xk2, *xmp;
1083 	int i, len, mlen;
1084 
1085 #ifdef DEBUG
1086 	if (rtfcdebug)
1087 		kprintf("rt_fixchange: rt %p, rt0 %p\n", rt, rt0);
1088 #endif
1089 
1090 	if (rt->rt_parent == NULL ||
1091 	    (rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) {
1092 #ifdef DEBUG
1093 		if (rtfcdebug) kprintf("no parent, pinned or cloning\n");
1094 #endif
1095 		return 0;
1096 	}
1097 
1098 	if (rt->rt_parent == rt0) {
1099 #ifdef DEBUG
1100 		if (rtfcdebug) kprintf("parent match\n");
1101 #endif
1102 		return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1103 				 rt->rt_flags, NULL);
1104 	}
1105 
1106 	/*
1107 	 * There probably is a function somewhere which does this...
1108 	 * if not, there should be.
1109 	 */
1110 	len = imin(rt_key(rt0)->sa_len, rt_key(rt)->sa_len);
1111 
1112 	xk1 = (u_char *)rt_key(rt0);
1113 	xm1 = (u_char *)rt_mask(rt0);
1114 	xk2 = (u_char *)rt_key(rt);
1115 
1116 	/* avoid applying a less specific route */
1117 	xmp = (u_char *)rt_mask(rt->rt_parent);
1118 	mlen = rt_key(rt->rt_parent)->sa_len;
1119 	if (mlen > rt_key(rt0)->sa_len) {
1120 #ifdef DEBUG
1121 		if (rtfcdebug)
1122 			kprintf("rt_fixchange: inserting a less "
1123 			       "specific route\n");
1124 #endif
1125 		return 0;
1126 	}
1127 	for (i = rnh->rnh_treetop->rn_offset; i < mlen; i++) {
1128 		if ((xmp[i] & ~(xmp[i] ^ xm1[i])) != xmp[i]) {
1129 #ifdef DEBUG
1130 			if (rtfcdebug)
1131 				kprintf("rt_fixchange: inserting a less "
1132 				       "specific route\n");
1133 #endif
1134 			return 0;
1135 		}
1136 	}
1137 
1138 	for (i = rnh->rnh_treetop->rn_offset; i < len; i++) {
1139 		if ((xk2[i] & xm1[i]) != xk1[i]) {
1140 #ifdef DEBUG
1141 			if (rtfcdebug) kprintf("no match\n");
1142 #endif
1143 			return 0;
1144 		}
1145 	}
1146 
1147 	/*
1148 	 * OK, this node is a clone, and matches the node currently being
1149 	 * changed/added under the node's mask.  So, get rid of it.
1150 	 */
1151 #ifdef DEBUG
1152 	if (rtfcdebug) kprintf("deleting\n");
1153 #endif
1154 	return rtrequest(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
1155 			 rt->rt_flags, NULL);
1156 }
1157 
1158 int
1159 rt_setgate(struct rtentry *rt0, struct sockaddr *dst, struct sockaddr *gate,
1160 	   boolean_t generate_report)
1161 {
1162 	char *space, *oldspace;
1163 	int dlen = RT_ROUNDUP(dst->sa_len), glen = RT_ROUNDUP(gate->sa_len);
1164 	struct rtentry *rt = rt0;
1165 	struct radix_node_head *rnh = rt_tables[mycpuid][dst->sa_family];
1166 
1167 	/*
1168 	 * A host route with the destination equal to the gateway
1169 	 * will interfere with keeping LLINFO in the routing
1170 	 * table, so disallow it.
1171 	 */
1172 	if (((rt0->rt_flags & (RTF_HOST | RTF_GATEWAY | RTF_LLINFO)) ==
1173 			      (RTF_HOST | RTF_GATEWAY)) &&
1174 	    dst->sa_len == gate->sa_len &&
1175 	    sa_equal(dst, gate)) {
1176 		/*
1177 		 * The route might already exist if this is an RTM_CHANGE
1178 		 * or a routing redirect, so try to delete it.
1179 		 */
1180 		if (rt_key(rt0) != NULL)
1181 			rtrequest(RTM_DELETE, rt_key(rt0), rt0->rt_gateway,
1182 				  rt_mask(rt0), rt0->rt_flags, NULL);
1183 		return EADDRNOTAVAIL;
1184 	}
1185 
1186 	/*
1187 	 * Both dst and gateway are stored in the same malloc'ed chunk
1188 	 * (If I ever get my hands on....)
1189 	 * if we need to malloc a new chunk, then keep the old one around
1190 	 * till we don't need it any more.
1191 	 */
1192 	if (rt->rt_gateway == NULL ||
1193 	    glen > RT_ROUNDUP(rt->rt_gateway->sa_len)) {
1194 		oldspace = (char *)rt_key(rt);
1195 		R_Malloc(space, char *, dlen + glen);
1196 		if (space == NULL)
1197 			return ENOBUFS;
1198 		rt->rt_nodes->rn_key = space;
1199 	} else {
1200 		space = (char *)rt_key(rt);	/* Just use the old space. */
1201 		oldspace = NULL;
1202 	}
1203 
1204 	/* Set the gateway value. */
1205 	rt->rt_gateway = (struct sockaddr *)(space + dlen);
1206 	bcopy(gate, rt->rt_gateway, glen);
1207 
1208 	if (oldspace != NULL) {
1209 		/*
1210 		 * If we allocated a new chunk, preserve the original dst.
1211 		 * This way, rt_setgate() really just sets the gate
1212 		 * and leaves the dst field alone.
1213 		 */
1214 		bcopy(dst, space, dlen);
1215 		Free(oldspace);
1216 	}
1217 
1218 	/*
1219 	 * If there is already a gwroute, it's now almost definitely wrong
1220 	 * so drop it.
1221 	 */
1222 	if (rt->rt_gwroute != NULL) {
1223 		RTFREE(rt->rt_gwroute);
1224 		rt->rt_gwroute = NULL;
1225 	}
1226 	if (rt->rt_flags & RTF_GATEWAY) {
1227 		/*
1228 		 * Cloning loop avoidance: In the presence of
1229 		 * protocol-cloning and bad configuration, it is
1230 		 * possible to get stuck in bottomless mutual recursion
1231 		 * (rtrequest rt_setgate rtlookup).  We avoid this
1232 		 * by not allowing protocol-cloning to operate for
1233 		 * gateways (which is probably the correct choice
1234 		 * anyway), and avoid the resulting reference loops
1235 		 * by disallowing any route to run through itself as
1236 		 * a gateway.  This is obviously mandatory when we
1237 		 * get rt->rt_output().
1238 		 *
1239 		 * This breaks TTCP for hosts outside the gateway!  XXX JH
1240 		 */
1241 		rt->rt_gwroute = _rtlookup(gate, generate_report,
1242 					   RTF_PRCLONING);
1243 		if (rt->rt_gwroute == rt) {
1244 			rt->rt_gwroute = NULL;
1245 			--rt->rt_refcnt;
1246 			return EDQUOT; /* failure */
1247 		}
1248 	}
1249 
1250 	/*
1251 	 * This isn't going to do anything useful for host routes, so
1252 	 * don't bother.  Also make sure we have a reasonable mask
1253 	 * (we don't yet have one during adds).
1254 	 */
1255 	if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != NULL) {
1256 		struct rtfc_arg arg = { rt, rnh };
1257 
1258 		rnh->rnh_walktree_from(rnh, (char *)rt_key(rt),
1259 				       (char *)rt_mask(rt),
1260 				       rt_fixchange, &arg);
1261 	}
1262 
1263 	return 0;
1264 }
1265 
1266 static void
1267 rt_maskedcopy(
1268 	struct sockaddr *src,
1269 	struct sockaddr *dst,
1270 	struct sockaddr *netmask)
1271 {
1272 	u_char *cp1 = (u_char *)src;
1273 	u_char *cp2 = (u_char *)dst;
1274 	u_char *cp3 = (u_char *)netmask;
1275 	u_char *cplim = cp2 + *cp3;
1276 	u_char *cplim2 = cp2 + *cp1;
1277 
1278 	*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
1279 	cp3 += 2;
1280 	if (cplim > cplim2)
1281 		cplim = cplim2;
1282 	while (cp2 < cplim)
1283 		*cp2++ = *cp1++ & *cp3++;
1284 	if (cp2 < cplim2)
1285 		bzero(cp2, cplim2 - cp2);
1286 }
1287 
1288 int
1289 rt_llroute(struct sockaddr *dst, struct rtentry *rt0, struct rtentry **drt)
1290 {
1291 	struct rtentry *up_rt, *rt;
1292 
1293 	if (!(rt0->rt_flags & RTF_UP)) {
1294 		up_rt = rtlookup(dst);
1295 		if (up_rt == NULL)
1296 			return (EHOSTUNREACH);
1297 		up_rt->rt_refcnt--;
1298 	} else
1299 		up_rt = rt0;
1300 	if (up_rt->rt_flags & RTF_GATEWAY) {
1301 		if (up_rt->rt_gwroute == NULL) {
1302 			up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1303 			if (up_rt->rt_gwroute == NULL)
1304 				return (EHOSTUNREACH);
1305 		} else if (!(up_rt->rt_gwroute->rt_flags & RTF_UP)) {
1306 			rtfree(up_rt->rt_gwroute);
1307 			up_rt->rt_gwroute = rtlookup(up_rt->rt_gateway);
1308 			if (up_rt->rt_gwroute == NULL)
1309 				return (EHOSTUNREACH);
1310 		}
1311 		rt = up_rt->rt_gwroute;
1312 	} else
1313 		rt = up_rt;
1314 	if (rt->rt_flags & RTF_REJECT &&
1315 	    (rt->rt_rmx.rmx_expire == 0 ||		/* rt doesn't expire */
1316 	     time_uptime < rt->rt_rmx.rmx_expire))	/* rt not expired */
1317 		return (rt->rt_flags & RTF_HOST ?  EHOSTDOWN : EHOSTUNREACH);
1318 	*drt = rt;
1319 	return 0;
1320 }
1321 
1322 static int
1323 rt_setshims(struct rtentry *rt, struct sockaddr **rt_shim){
1324 	int i;
1325 
1326 	for (i=0; i<3; i++) {
1327 		struct sockaddr *shim = rt_shim[RTAX_MPLS1 + i];
1328 		int shimlen;
1329 
1330 		if (shim == NULL)
1331 			break;
1332 
1333 		shimlen = RT_ROUNDUP(shim->sa_len);
1334 		R_Malloc(rt->rt_shim[i], struct sockaddr *, shimlen);
1335 		bcopy(shim, rt->rt_shim[i], shimlen);
1336 	}
1337 
1338 	return 0;
1339 }
1340 
1341 #ifdef ROUTE_DEBUG
1342 
1343 /*
1344  * Print out a route table entry
1345  */
1346 void
1347 rt_print(struct rt_addrinfo *rtinfo, struct rtentry *rn)
1348 {
1349 	kprintf("rti %p cpu %d route %p flags %08lx: ",
1350 		rtinfo, mycpuid, rn, rn->rt_flags);
1351 	sockaddr_print(rt_key(rn));
1352 	kprintf(" mask ");
1353 	sockaddr_print(rt_mask(rn));
1354 	kprintf(" gw ");
1355 	sockaddr_print(rn->rt_gateway);
1356 	kprintf(" ifc \"%s\"", rn->rt_ifp ? rn->rt_ifp->if_dname : "?");
1357 	kprintf(" ifa %p\n", rn->rt_ifa);
1358 }
1359 
1360 void
1361 rt_addrinfo_print(int cmd, struct rt_addrinfo *rti)
1362 {
1363 	int didit = 0;
1364 	int i;
1365 
1366 #ifdef ROUTE_DEBUG
1367 	if (cmd == RTM_DELETE && route_debug > 1)
1368 		print_backtrace(-1);
1369 #endif
1370 
1371 	switch(cmd) {
1372 	case RTM_ADD:
1373 		kprintf("ADD ");
1374 		break;
1375 	case RTM_RESOLVE:
1376 		kprintf("RES ");
1377 		break;
1378 	case RTM_DELETE:
1379 		kprintf("DEL ");
1380 		break;
1381 	default:
1382 		kprintf("C%02d ", cmd);
1383 		break;
1384 	}
1385 	kprintf("rti %p cpu %d ", rti, mycpuid);
1386 	for (i = 0; i < rti->rti_addrs; ++i) {
1387 		if (rti->rti_info[i] == NULL)
1388 			continue;
1389 		if (didit)
1390 			kprintf(" ,");
1391 		switch(i) {
1392 		case RTAX_DST:
1393 			kprintf("(DST ");
1394 			break;
1395 		case RTAX_GATEWAY:
1396 			kprintf("(GWY ");
1397 			break;
1398 		case RTAX_NETMASK:
1399 			kprintf("(MSK ");
1400 			break;
1401 		case RTAX_GENMASK:
1402 			kprintf("(GEN ");
1403 			break;
1404 		case RTAX_IFP:
1405 			kprintf("(IFP ");
1406 			break;
1407 		case RTAX_IFA:
1408 			kprintf("(IFA ");
1409 			break;
1410 		case RTAX_AUTHOR:
1411 			kprintf("(AUT ");
1412 			break;
1413 		case RTAX_BRD:
1414 			kprintf("(BRD ");
1415 			break;
1416 		default:
1417 			kprintf("(?%02d ", i);
1418 			break;
1419 		}
1420 		sockaddr_print(rti->rti_info[i]);
1421 		kprintf(")");
1422 		didit = 1;
1423 	}
1424 	kprintf("\n");
1425 }
1426 
1427 void
1428 sockaddr_print(struct sockaddr *sa)
1429 {
1430 	struct sockaddr_in *sa4;
1431 	struct sockaddr_in6 *sa6;
1432 	int len;
1433 	int i;
1434 
1435 	if (sa == NULL) {
1436 		kprintf("NULL");
1437 		return;
1438 	}
1439 
1440 	len = sa->sa_len - offsetof(struct sockaddr, sa_data[0]);
1441 
1442 	switch(sa->sa_family) {
1443 	case AF_INET:
1444 	case AF_INET6:
1445 	default:
1446 		switch(sa->sa_family) {
1447 		case AF_INET:
1448 			sa4 = (struct sockaddr_in *)sa;
1449 			kprintf("INET %d %d.%d.%d.%d",
1450 				ntohs(sa4->sin_port),
1451 				(ntohl(sa4->sin_addr.s_addr) >> 24) & 255,
1452 				(ntohl(sa4->sin_addr.s_addr) >> 16) & 255,
1453 				(ntohl(sa4->sin_addr.s_addr) >> 8) & 255,
1454 				(ntohl(sa4->sin_addr.s_addr) >> 0) & 255
1455 			);
1456 			break;
1457 		case AF_INET6:
1458 			sa6 = (struct sockaddr_in6 *)sa;
1459 			kprintf("INET6 %d %04x:%04x%04x:%04x:%04x:%04x:%04x:%04x",
1460 				ntohs(sa6->sin6_port),
1461 				sa6->sin6_addr.s6_addr16[0],
1462 				sa6->sin6_addr.s6_addr16[1],
1463 				sa6->sin6_addr.s6_addr16[2],
1464 				sa6->sin6_addr.s6_addr16[3],
1465 				sa6->sin6_addr.s6_addr16[4],
1466 				sa6->sin6_addr.s6_addr16[5],
1467 				sa6->sin6_addr.s6_addr16[6],
1468 				sa6->sin6_addr.s6_addr16[7]
1469 			);
1470 			break;
1471 		default:
1472 			kprintf("AF%d ", sa->sa_family);
1473 			while (len > 0 && sa->sa_data[len-1] == 0)
1474 				--len;
1475 
1476 			for (i = 0; i < len; ++i) {
1477 				if (i)
1478 					kprintf(".");
1479 				kprintf("%d", (unsigned char)sa->sa_data[i]);
1480 			}
1481 			break;
1482 		}
1483 	}
1484 }
1485 
1486 #endif
1487 
1488 /*
1489  * Set up a routing table entry, normally for an interface.
1490  */
1491 int
1492 rtinit(struct ifaddr *ifa, int cmd, int flags)
1493 {
1494 	struct sockaddr *dst, *deldst, *netmask;
1495 	struct mbuf *m = NULL;
1496 	struct radix_node_head *rnh;
1497 	struct radix_node *rn;
1498 	struct rt_addrinfo rtinfo;
1499 	int error;
1500 
1501 	if (flags & RTF_HOST) {
1502 		dst = ifa->ifa_dstaddr;
1503 		netmask = NULL;
1504 	} else {
1505 		dst = ifa->ifa_addr;
1506 		netmask = ifa->ifa_netmask;
1507 	}
1508 	/*
1509 	 * If it's a delete, check that if it exists, it's on the correct
1510 	 * interface or we might scrub a route to another ifa which would
1511 	 * be confusing at best and possibly worse.
1512 	 */
1513 	if (cmd == RTM_DELETE) {
1514 		/*
1515 		 * It's a delete, so it should already exist..
1516 		 * If it's a net, mask off the host bits
1517 		 * (Assuming we have a mask)
1518 		 */
1519 		if (netmask != NULL) {
1520 			m = m_get(MB_DONTWAIT, MT_SONAME);
1521 			if (m == NULL)
1522 				return (ENOBUFS);
1523 			mbuftrackid(m, 34);
1524 			deldst = mtod(m, struct sockaddr *);
1525 			rt_maskedcopy(dst, deldst, netmask);
1526 			dst = deldst;
1527 		}
1528 		/*
1529 		 * Look up an rtentry that is in the routing tree and
1530 		 * contains the correct info.
1531 		 */
1532 		if ((rnh = rt_tables[mycpuid][dst->sa_family]) == NULL ||
1533 		    (rn = rnh->rnh_lookup((char *)dst,
1534 					  (char *)netmask, rnh)) == NULL ||
1535 		    ((struct rtentry *)rn)->rt_ifa != ifa ||
1536 		    !sa_equal((struct sockaddr *)rn->rn_key, dst)) {
1537 			if (m != NULL)
1538 				m_free(m);
1539 			return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1540 		}
1541 		/* XXX */
1542 #if 0
1543 		else {
1544 			/*
1545 			 * One would think that as we are deleting, and we know
1546 			 * it doesn't exist, we could just return at this point
1547 			 * with an "ELSE" clause, but apparently not..
1548 			 */
1549 			return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
1550 		}
1551 #endif
1552 	}
1553 	/*
1554 	 * Do the actual request
1555 	 */
1556 	bzero(&rtinfo, sizeof(struct rt_addrinfo));
1557 	rtinfo.rti_info[RTAX_DST] = dst;
1558 	rtinfo.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
1559 	rtinfo.rti_info[RTAX_NETMASK] = netmask;
1560 	rtinfo.rti_flags = flags | ifa->ifa_flags;
1561 	rtinfo.rti_ifa = ifa;
1562 	error = rtrequest1_global(cmd, &rtinfo, rtinit_rtrequest_callback, ifa,
1563 	    RTREQ_PRIO_HIGH);
1564 	if (m != NULL)
1565 		m_free(m);
1566 	return (error);
1567 }
1568 
1569 static void
1570 rtinit_rtrequest_callback(int cmd, int error,
1571 			  struct rt_addrinfo *rtinfo, struct rtentry *rt,
1572 			  void *arg)
1573 {
1574 	struct ifaddr *ifa = arg;
1575 
1576 	if (error == 0 && rt) {
1577 		if (mycpuid == 0) {
1578 			++rt->rt_refcnt;
1579 			rt_newaddrmsg(cmd, ifa, error, rt);
1580 			--rt->rt_refcnt;
1581 		}
1582 		if (cmd == RTM_DELETE) {
1583 			if (rt->rt_refcnt == 0) {
1584 				++rt->rt_refcnt;
1585 				rtfree(rt);
1586 			}
1587 		}
1588 	}
1589 }
1590 
1591 struct netmsg_rts {
1592 	struct netmsg_base	base;
1593 	int			req;
1594 	struct rt_addrinfo	*rtinfo;
1595 	rtsearch_callback_func_t callback;
1596 	void			*arg;
1597 	boolean_t		exact_match;
1598 	int			found_cnt;
1599 };
1600 
1601 int
1602 rtsearch_global(int req, struct rt_addrinfo *rtinfo,
1603     rtsearch_callback_func_t callback, void *arg, boolean_t exact_match,
1604     boolean_t req_prio)
1605 {
1606 	struct netmsg_rts msg;
1607 	int flags = 0;
1608 
1609 	if (req_prio)
1610 		flags = MSGF_PRIORITY;
1611 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, flags,
1612 	    rtsearch_msghandler);
1613 	msg.req = req;
1614 	msg.rtinfo = rtinfo;
1615 	msg.callback = callback;
1616 	msg.arg = arg;
1617 	msg.exact_match = exact_match;
1618 	msg.found_cnt = 0;
1619 	return rt_domsg_global(&msg.base);
1620 }
1621 
1622 static void
1623 rtsearch_msghandler(netmsg_t msg)
1624 {
1625 	struct netmsg_rts *rmsg = (void *)msg;
1626 	struct rt_addrinfo rtinfo;
1627 	struct radix_node_head *rnh;
1628 	struct rtentry *rt;
1629 	int nextcpu, error;
1630 
1631 	/*
1632 	 * Copy the rtinfo.  We need to make sure that the original
1633 	 * rtinfo, which is setup by the caller, in the netmsg will
1634 	 * _not_ be changed; else the next CPU on the netmsg forwarding
1635 	 * path will see a different rtinfo than what this CPU has seen.
1636 	 */
1637 	rtinfo = *rmsg->rtinfo;
1638 
1639 	/*
1640 	 * Find the correct routing tree to use for this Address Family
1641 	 */
1642 	if ((rnh = rt_tables[mycpuid][rtinfo.rti_dst->sa_family]) == NULL) {
1643 		if (mycpuid != 0)
1644 			panic("partially initialized routing tables");
1645 		lwkt_replymsg(&rmsg->base.lmsg, EAFNOSUPPORT);
1646 		return;
1647 	}
1648 
1649 	/*
1650 	 * Correct rtinfo for the host route searching.
1651 	 */
1652 	if (rtinfo.rti_flags & RTF_HOST) {
1653 		rtinfo.rti_netmask = NULL;
1654 		rtinfo.rti_flags &= ~(RTF_CLONING | RTF_PRCLONING);
1655 	}
1656 
1657 	rt = (struct rtentry *)
1658 	     rnh->rnh_lookup((char *)rtinfo.rti_dst,
1659 			     (char *)rtinfo.rti_netmask, rnh);
1660 
1661 	/*
1662 	 * If we are asked to do the "exact match", we need to make sure
1663 	 * that host route searching got a host route while a network
1664 	 * route searching got a network route.
1665 	 */
1666 	if (rt != NULL && rmsg->exact_match &&
1667 	    ((rt->rt_flags ^ rtinfo.rti_flags) & RTF_HOST))
1668 		rt = NULL;
1669 
1670 	if (rt == NULL) {
1671 		/*
1672 		 * No matching routes have been found, don't count this
1673 		 * as a critical error (here, we set 'error' to 0), just
1674 		 * keep moving on, since at least prcloned routes are not
1675 		 * duplicated onto each CPU.
1676 		 */
1677 		error = 0;
1678 	} else {
1679 		rmsg->found_cnt++;
1680 
1681 		rt->rt_refcnt++;
1682 		error = rmsg->callback(rmsg->req, &rtinfo, rt, rmsg->arg,
1683 				      rmsg->found_cnt);
1684 		rt->rt_refcnt--;
1685 
1686 		if (error == EJUSTRETURN) {
1687 			lwkt_replymsg(&rmsg->base.lmsg, 0);
1688 			return;
1689 		}
1690 	}
1691 
1692 	nextcpu = mycpuid + 1;
1693 	if (error) {
1694 		KKASSERT(rmsg->found_cnt > 0);
1695 
1696 		/*
1697 		 * Under following cases, unrecoverable error has
1698 		 * not occured:
1699 		 * o  Request is RTM_GET
1700 		 * o  The first time that we find the route, but the
1701 		 *    modification fails.
1702 		 */
1703 		if (rmsg->req != RTM_GET && rmsg->found_cnt > 1) {
1704 			panic("rtsearch_msghandler: unrecoverable error "
1705 			      "cpu %d", mycpuid);
1706 		}
1707 		lwkt_replymsg(&rmsg->base.lmsg, error);
1708 	} else if (nextcpu < ncpus) {
1709 		lwkt_forwardmsg(netisr_cpuport(nextcpu), &rmsg->base.lmsg);
1710 	} else {
1711 		if (rmsg->found_cnt == 0) {
1712 			/* The requested route was never seen ... */
1713 			error = ESRCH;
1714 		}
1715 		lwkt_replymsg(&rmsg->base.lmsg, error);
1716 	}
1717 }
1718 
1719 int
1720 rtmask_add_global(struct sockaddr *mask, boolean_t req_prio)
1721 {
1722 	struct netmsg_base msg;
1723 	int flags = 0;
1724 
1725 	if (req_prio)
1726 		flags = MSGF_PRIORITY;
1727 	netmsg_init(&msg, NULL, &curthread->td_msgport, flags,
1728 	    rtmask_add_msghandler);
1729 	msg.lmsg.u.ms_resultp = mask;
1730 
1731 	return rt_domsg_global(&msg);
1732 }
1733 
1734 struct sockaddr *
1735 _rtmask_lookup(struct sockaddr *mask, boolean_t search)
1736 {
1737 	struct radix_node *n;
1738 
1739 #define	clen(s)	(*(u_char *)(s))
1740 	n = rn_addmask((char *)mask, search, 1, rn_cpumaskhead(mycpuid));
1741 	if (n != NULL &&
1742 	    mask->sa_len >= clen(n->rn_key) &&
1743 	    bcmp((char *)mask + 1,
1744 		 (char *)n->rn_key + 1, clen(n->rn_key) - 1) == 0) {
1745 		return (struct sockaddr *)n->rn_key;
1746 	} else {
1747 		return NULL;
1748 	}
1749 #undef clen
1750 }
1751 
1752 static void
1753 rtmask_add_msghandler(netmsg_t msg)
1754 {
1755 	struct lwkt_msg *lmsg = &msg->lmsg;
1756 	struct sockaddr *mask = lmsg->u.ms_resultp;
1757 	int error = 0, nextcpu;
1758 
1759 	if (rtmask_lookup(mask) == NULL)
1760 		error = ENOBUFS;
1761 
1762 	nextcpu = mycpuid + 1;
1763 	if (!error && nextcpu < ncpus)
1764 		lwkt_forwardmsg(netisr_cpuport(nextcpu), lmsg);
1765 	else
1766 		lwkt_replymsg(lmsg, error);
1767 }
1768 
1769 /* This must be before ip6_init2(), which is now SI_ORDER_MIDDLE */
1770 SYSINIT(route, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, 0);
1771 
1772 struct rtchange_arg {
1773 	struct ifaddr	*old_ifa;
1774 	struct ifaddr	*new_ifa;
1775 	struct rtentry	*rt;
1776 	int		changed;
1777 };
1778 
1779 static void
1780 rtchange_ifa(struct rtentry *rt, struct rtchange_arg *ap)
1781 {
1782 	if (rt->rt_ifa->ifa_rtrequest != NULL)
1783 		rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt);
1784 	IFAFREE(rt->rt_ifa);
1785 
1786 	IFAREF(ap->new_ifa);
1787 	rt->rt_ifa = ap->new_ifa;
1788 	rt->rt_ifp = ap->new_ifa->ifa_ifp;
1789 	if (rt->rt_ifa->ifa_rtrequest != NULL)
1790 		rt->rt_ifa->ifa_rtrequest(RTM_ADD, rt);
1791 
1792 	ap->changed = 1;
1793 }
1794 
1795 static int
1796 rtchange_callback(struct radix_node *rn, void *xap)
1797 {
1798 	struct rtchange_arg *ap = xap;
1799 	struct rtentry *rt = (struct rtentry *)rn;
1800 
1801 	if (rt->rt_ifa == ap->old_ifa) {
1802 		if (rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) {
1803 			/*
1804 			 * We could saw the branch off when we are
1805 			 * still sitting on it, if the ifa_rtrequest
1806 			 * DEL/ADD are called directly from here.
1807 			 */
1808 			ap->rt = rt;
1809 			return EJUSTRETURN;
1810 		}
1811 		rtchange_ifa(rt, ap);
1812 	}
1813 	return 0;
1814 }
1815 
1816 struct netmsg_rtchange {
1817 	struct netmsg_base	base;
1818 	struct ifaddr		*old_ifa;
1819 	struct ifaddr		*new_ifa;
1820 	int			changed;
1821 };
1822 
1823 static void
1824 rtchange_dispatch(netmsg_t msg)
1825 {
1826 	struct netmsg_rtchange *rmsg = (void *)msg;
1827 	struct radix_node_head *rnh;
1828 	struct rtchange_arg arg;
1829 	int nextcpu, cpu;
1830 
1831 	cpu = mycpuid;
1832 
1833 	memset(&arg, 0, sizeof(arg));
1834 	arg.old_ifa = rmsg->old_ifa;
1835 	arg.new_ifa = rmsg->new_ifa;
1836 
1837 	rnh = rt_tables[cpu][AF_INET];
1838 	for (;;) {
1839 		int error;
1840 
1841 		KKASSERT(arg.rt == NULL);
1842 		error = rnh->rnh_walktree(rnh, rtchange_callback, &arg);
1843 		if (arg.rt != NULL) {
1844 			struct rtentry *rt;
1845 
1846 			rt = arg.rt;
1847 			arg.rt = NULL;
1848 			rtchange_ifa(rt, &arg);
1849 		} else {
1850 			break;
1851 		}
1852 	}
1853 	if (arg.changed)
1854 		rmsg->changed = 1;
1855 
1856 	nextcpu = cpu + 1;
1857 	if (nextcpu < ncpus)
1858 		lwkt_forwardmsg(netisr_cpuport(nextcpu), &rmsg->base.lmsg);
1859 	else
1860 		lwkt_replymsg(&rmsg->base.lmsg, 0);
1861 }
1862 
1863 int
1864 rtchange(struct ifaddr *old_ifa, struct ifaddr *new_ifa)
1865 {
1866 	struct netmsg_rtchange msg;
1867 
1868 	/*
1869 	 * XXX individual requests are not independantly chained,
1870 	 * which means that the per-cpu route tables will not be
1871 	 * consistent in the middle of the operation.  If routes
1872 	 * related to the interface are manipulated while we are
1873 	 * doing this the inconsistancy could trigger a panic.
1874 	 */
1875 	netmsg_init(&msg.base, NULL, &curthread->td_msgport, MSGF_PRIORITY,
1876 	    rtchange_dispatch);
1877 	msg.old_ifa = old_ifa;
1878 	msg.new_ifa = new_ifa;
1879 	msg.changed = 0;
1880 	rt_domsg_global(&msg.base);
1881 
1882 	if (msg.changed) {
1883 		old_ifa->ifa_flags &= ~IFA_ROUTE;
1884 		new_ifa->ifa_flags |= IFA_ROUTE;
1885 		return 0;
1886 	} else {
1887 		return ENOENT;
1888 	}
1889 }
1890 
1891 int
1892 rt_domsg_global(struct netmsg_base *nmsg)
1893 {
1894 	ASSERT_CANDOMSG_NETISR0(curthread);
1895 	return lwkt_domsg(netisr_cpuport(0), &nmsg->lmsg, 0);
1896 }
1897