xref: /netbsd-src/sys/net/route.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: route.c,v 1.36 2000/03/30 09:45:40 augustss Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Kevin M. Lahey of the Numerical Aerospace Simulation Facility,
9  * NASA Ames Research Center.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the NetBSD
22  *	Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
42  * All rights reserved.
43  *
44  * Redistribution and use in source and binary forms, with or without
45  * modification, are permitted provided that the following conditions
46  * are met:
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  * 3. Neither the name of the project nor the names of its contributors
53  *    may be used to endorse or promote products derived from this software
54  *    without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
57  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
60  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  */
68 
69 /*
70  * Copyright (c) 1980, 1986, 1991, 1993
71  *	The Regents of the University of California.  All rights reserved.
72  *
73  * Redistribution and use in source and binary forms, with or without
74  * modification, are permitted provided that the following conditions
75  * are met:
76  * 1. Redistributions of source code must retain the above copyright
77  *    notice, this list of conditions and the following disclaimer.
78  * 2. Redistributions in binary form must reproduce the above copyright
79  *    notice, this list of conditions and the following disclaimer in the
80  *    documentation and/or other materials provided with the distribution.
81  * 3. All advertising materials mentioning features or use of this software
82  *    must display the following acknowledgement:
83  *	This product includes software developed by the University of
84  *	California, Berkeley and its contributors.
85  * 4. Neither the name of the University nor the names of its contributors
86  *    may be used to endorse or promote products derived from this software
87  *    without specific prior written permission.
88  *
89  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
90  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
91  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
92  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
93  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
94  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
95  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
96  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
97  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
98  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
99  * SUCH DAMAGE.
100  *
101  *	@(#)route.c	8.3 (Berkeley) 1/9/95
102  */
103 
104 #include "opt_ns.h"
105 
106 #include <sys/param.h>
107 #include <sys/systm.h>
108 #include <sys/callout.h>
109 #include <sys/proc.h>
110 #include <sys/mbuf.h>
111 #include <sys/socket.h>
112 #include <sys/socketvar.h>
113 #include <sys/domain.h>
114 #include <sys/protosw.h>
115 #include <sys/kernel.h>
116 #include <sys/ioctl.h>
117 #include <sys/pool.h>
118 
119 #include <net/if.h>
120 #include <net/route.h>
121 #include <net/raw_cb.h>
122 
123 #include <netinet/in.h>
124 #include <netinet/in_var.h>
125 
126 #ifdef NS
127 #include <netns/ns.h>
128 #endif
129 
130 #define	SA(p) ((struct sockaddr *)(p))
131 
132 int	rttrash;		/* routes not in table but not freed */
133 struct	sockaddr wildcard;	/* zero valued cookie for wildcard searches */
134 
135 struct pool rtentry_pool;	/* pool for rtentry structures */
136 struct pool rttimer_pool;	/* pool for rttimer structures */
137 
138 struct callout rt_timer_ch; /* callout for rt_timer_timer() */
139 
140 void
141 rtable_init(table)
142 	void **table;
143 {
144 	struct domain *dom;
145 	for (dom = domains; dom; dom = dom->dom_next)
146 		if (dom->dom_rtattach)
147 			dom->dom_rtattach(&table[dom->dom_family],
148 			    dom->dom_rtoffset);
149 }
150 
151 void
152 route_init()
153 {
154 
155 	pool_init(&rtentry_pool, sizeof(struct rtentry), 0, 0, 0, "rtentpl",
156 	    0, NULL, NULL, M_RTABLE);
157 
158 	rn_init();	/* initialize all zeroes, all ones, mask table */
159 	rtable_init((void **)rt_tables);
160 }
161 
162 /*
163  * Packet routing routines.
164  */
165 void
166 rtalloc(ro)
167 	struct route *ro;
168 {
169 	if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
170 		return;				 /* XXX */
171 	ro->ro_rt = rtalloc1(&ro->ro_dst, 1);
172 }
173 
174 struct rtentry *
175 rtalloc1(dst, report)
176 	struct sockaddr *dst;
177 	int report;
178 {
179 	struct radix_node_head *rnh = rt_tables[dst->sa_family];
180 	struct rtentry *rt;
181 	struct radix_node *rn;
182 	struct rtentry *newrt = 0;
183 	struct rt_addrinfo info;
184 	int  s = splsoftnet(), err = 0, msgtype = RTM_MISS;
185 
186 	if (rnh && (rn = rnh->rnh_matchaddr((caddr_t)dst, rnh)) &&
187 	    ((rn->rn_flags & RNF_ROOT) == 0)) {
188 		newrt = rt = (struct rtentry *)rn;
189 		if (report && (rt->rt_flags & RTF_CLONING)) {
190 			err = rtrequest(RTM_RESOLVE, dst, SA(0),
191 					      SA(0), 0, &newrt);
192 			if (err) {
193 				newrt = rt;
194 				rt->rt_refcnt++;
195 				goto miss;
196 			}
197 			if ((rt = newrt) && (rt->rt_flags & RTF_XRESOLVE)) {
198 				msgtype = RTM_RESOLVE;
199 				goto miss;
200 			}
201 		} else
202 			rt->rt_refcnt++;
203 	} else {
204 		rtstat.rts_unreach++;
205 	miss:	if (report) {
206 			bzero((caddr_t)&info, sizeof(info));
207 			info.rti_info[RTAX_DST] = dst;
208 			rt_missmsg(msgtype, &info, 0, err);
209 		}
210 	}
211 	splx(s);
212 	return (newrt);
213 }
214 
215 void
216 rtfree(rt)
217 	struct rtentry *rt;
218 {
219 	struct ifaddr *ifa;
220 
221 	if (rt == 0)
222 		panic("rtfree");
223 	rt->rt_refcnt--;
224 	if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_UP) == 0) {
225 		if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT))
226 			panic ("rtfree 2");
227 		rttrash--;
228 		if (rt->rt_refcnt < 0) {
229 			printf("rtfree: %p not freed (neg refs)\n", rt);
230 			return;
231 		}
232 		rt_timer_remove_all(rt);
233 		ifa = rt->rt_ifa;
234 		IFAFREE(ifa);
235 		Free(rt_key(rt));
236 		pool_put(&rtentry_pool, rt);
237 	}
238 }
239 
240 void
241 ifafree(ifa)
242 	struct ifaddr *ifa;
243 {
244 
245 #ifdef DIAGNOSTIC
246 	if (ifa == NULL)
247 		panic("ifafree: null ifa");
248 	if (ifa->ifa_refcnt != 0)
249 		panic("ifafree: ifa_refcnt != 0 (%d)", ifa->ifa_refcnt);
250 #endif
251 #ifdef IFAREF_DEBUG
252 	printf("ifafree: freeing ifaddr %p\n", ifa);
253 #endif
254 	free(ifa, M_IFADDR);
255 }
256 
257 /*
258  * Force a routing table entry to the specified
259  * destination to go through the given gateway.
260  * Normally called as a result of a routing redirect
261  * message from the network layer.
262  *
263  * N.B.: must be called at splsoftnet
264  */
265 void
266 rtredirect(dst, gateway, netmask, flags, src, rtp)
267 	struct sockaddr *dst, *gateway, *netmask, *src;
268 	int flags;
269 	struct rtentry **rtp;
270 {
271 	struct rtentry *rt;
272 	int error = 0;
273 	short *stat = 0;
274 	struct rt_addrinfo info;
275 	struct ifaddr *ifa;
276 
277 	/* verify the gateway is directly reachable */
278 	if ((ifa = ifa_ifwithnet(gateway)) == 0) {
279 		error = ENETUNREACH;
280 		goto out;
281 	}
282 	rt = rtalloc1(dst, 0);
283 	/*
284 	 * If the redirect isn't from our current router for this dst,
285 	 * it's either old or wrong.  If it redirects us to ourselves,
286 	 * we have a routing loop, perhaps as a result of an interface
287 	 * going down recently.
288 	 */
289 #define	equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0)
290 	if (!(flags & RTF_DONE) && rt &&
291 	     (!equal(src, rt->rt_gateway) || rt->rt_ifa != ifa))
292 		error = EINVAL;
293 	else if (ifa_ifwithaddr(gateway))
294 		error = EHOSTUNREACH;
295 	if (error)
296 		goto done;
297 	/*
298 	 * Create a new entry if we just got back a wildcard entry
299 	 * or the lookup failed.  This is necessary for hosts
300 	 * which use routing redirects generated by smart gateways
301 	 * to dynamically build the routing tables.
302 	 */
303 	if ((rt == 0) || (rt_mask(rt) && rt_mask(rt)->sa_len < 2))
304 		goto create;
305 	/*
306 	 * Don't listen to the redirect if it's
307 	 * for a route to an interface.
308 	 */
309 	if (rt->rt_flags & RTF_GATEWAY) {
310 		if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) {
311 			/*
312 			 * Changing from route to net => route to host.
313 			 * Create new route, rather than smashing route to net.
314 			 */
315 		create:
316 			flags |=  RTF_GATEWAY | RTF_DYNAMIC;
317 			error = rtrequest((int)RTM_ADD, dst, gateway,
318 				    netmask, flags,
319 				    (struct rtentry **)0);
320 			stat = &rtstat.rts_dynamic;
321 		} else {
322 			/*
323 			 * Smash the current notion of the gateway to
324 			 * this destination.  Should check about netmask!!!
325 			 */
326 			rt->rt_flags |= RTF_MODIFIED;
327 			flags |= RTF_MODIFIED;
328 			stat = &rtstat.rts_newgateway;
329 			rt_setgate(rt, rt_key(rt), gateway);
330 		}
331 	} else
332 		error = EHOSTUNREACH;
333 done:
334 	if (rt) {
335 		if (rtp && !error)
336 			*rtp = rt;
337 		else
338 			rtfree(rt);
339 	}
340 out:
341 	if (error)
342 		rtstat.rts_badredirect++;
343 	else if (stat != NULL)
344 		(*stat)++;
345 	bzero((caddr_t)&info, sizeof(info));
346 	info.rti_info[RTAX_DST] = dst;
347 	info.rti_info[RTAX_GATEWAY] = gateway;
348 	info.rti_info[RTAX_NETMASK] = netmask;
349 	info.rti_info[RTAX_AUTHOR] = src;
350 	rt_missmsg(RTM_REDIRECT, &info, flags, error);
351 }
352 
353 /*
354  * Routing table ioctl interface.
355  */
356 int
357 rtioctl(req, data, p)
358 	u_long req;
359 	caddr_t data;
360 	struct proc *p;
361 {
362 	return (EOPNOTSUPP);
363 }
364 
365 struct ifaddr *
366 ifa_ifwithroute(flags, dst, gateway)
367 	int flags;
368 	struct sockaddr	*dst, *gateway;
369 {
370 	struct ifaddr *ifa;
371 	if ((flags & RTF_GATEWAY) == 0) {
372 		/*
373 		 * If we are adding a route to an interface,
374 		 * and the interface is a pt to pt link
375 		 * we should search for the destination
376 		 * as our clue to the interface.  Otherwise
377 		 * we can use the local address.
378 		 */
379 		ifa = 0;
380 		if (flags & RTF_HOST)
381 			ifa = ifa_ifwithdstaddr(dst);
382 		if (ifa == 0)
383 			ifa = ifa_ifwithaddr(gateway);
384 	} else {
385 		/*
386 		 * If we are adding a route to a remote net
387 		 * or host, the gateway may still be on the
388 		 * other end of a pt to pt link.
389 		 */
390 		ifa = ifa_ifwithdstaddr(gateway);
391 	}
392 	if (ifa == 0)
393 		ifa = ifa_ifwithnet(gateway);
394 	if (ifa == 0) {
395 		struct rtentry *rt = rtalloc1(dst, 0);
396 		if (rt == 0)
397 			return (0);
398 		rt->rt_refcnt--;
399 		if ((ifa = rt->rt_ifa) == 0)
400 			return (0);
401 	}
402 	if (ifa->ifa_addr->sa_family != dst->sa_family) {
403 		struct ifaddr *oifa = ifa;
404 		ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
405 		if (ifa == 0)
406 			ifa = oifa;
407 	}
408 	return (ifa);
409 }
410 
411 #define ROUNDUP(a) (a>0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
412 
413 int
414 rtrequest(req, dst, gateway, netmask, flags, ret_nrt)
415 	int req, flags;
416 	struct sockaddr *dst, *gateway, *netmask;
417 	struct rtentry **ret_nrt;
418 {
419 	int s = splsoftnet(); int error = 0;
420 	struct rtentry *rt;
421 	struct radix_node *rn;
422 	struct radix_node_head *rnh;
423 	struct ifaddr *ifa;
424 	struct sockaddr *ndst;
425 #define senderr(x) { error = x ; goto bad; }
426 
427 	if ((rnh = rt_tables[dst->sa_family]) == 0)
428 		senderr(ESRCH);
429 	if (flags & RTF_HOST)
430 		netmask = 0;
431 	switch (req) {
432 	case RTM_DELETE:
433 		if ((rn = rnh->rnh_deladdr(dst, netmask, rnh)) == 0)
434 			senderr(ESRCH);
435 		if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT))
436 			panic ("rtrequest delete");
437 		rt = (struct rtentry *)rn;
438 		if (rt->rt_gwroute) {
439 			rt = rt->rt_gwroute; RTFREE(rt);
440 			(rt = (struct rtentry *)rn)->rt_gwroute = 0;
441 		}
442 		rt->rt_flags &= ~RTF_UP;
443 		if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
444 			ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
445 		rttrash++;
446 		if (ret_nrt)
447 			*ret_nrt = rt;
448 		else if (rt->rt_refcnt <= 0) {
449 			rt->rt_refcnt++;
450 			rtfree(rt);
451 		}
452 		break;
453 
454 	case RTM_RESOLVE:
455 		if (ret_nrt == 0 || (rt = *ret_nrt) == 0)
456 			senderr(EINVAL);
457 		ifa = rt->rt_ifa;
458 		flags = rt->rt_flags & ~RTF_CLONING;
459 		gateway = rt->rt_gateway;
460 		if ((netmask = rt->rt_genmask) == 0)
461 			flags |= RTF_HOST;
462 		goto makeroute;
463 
464 	case RTM_ADD:
465 		if ((ifa = ifa_ifwithroute(flags, dst, gateway)) == 0)
466 			senderr(ENETUNREACH);
467 	makeroute:
468 		rt = pool_get(&rtentry_pool, PR_NOWAIT);
469 		if (rt == 0)
470 			senderr(ENOBUFS);
471 		Bzero(rt, sizeof(*rt));
472 		rt->rt_flags = RTF_UP | flags;
473 		LIST_INIT(&rt->rt_timer);
474 		if (rt_setgate(rt, dst, gateway)) {
475 			pool_put(&rtentry_pool, rt);
476 			senderr(ENOBUFS);
477 		}
478 		ndst = rt_key(rt);
479 		if (netmask) {
480 			rt_maskedcopy(dst, ndst, netmask);
481 		} else
482 			Bcopy(dst, ndst, dst->sa_len);
483 		rn = rnh->rnh_addaddr((caddr_t)ndst, (caddr_t)netmask,
484 					rnh, rt->rt_nodes);
485 		if (rn == 0) {
486 			if (rt->rt_gwroute)
487 				rtfree(rt->rt_gwroute);
488 			Free(rt_key(rt));
489 			pool_put(&rtentry_pool, rt);
490 			senderr(EEXIST);
491 		}
492 		IFAREF(ifa);
493 		rt->rt_ifa = ifa;
494 		rt->rt_ifp = ifa->ifa_ifp;
495 		if (req == RTM_RESOLVE) {
496 			rt->rt_rmx = (*ret_nrt)->rt_rmx; /* copy metrics */
497 		} else if (rt->rt_rmx.rmx_mtu == 0
498 			    && !(rt->rt_rmx.rmx_locks & RTV_MTU)) { /* XXX */
499 			if (rt->rt_gwroute != NULL) {
500 				rt->rt_rmx.rmx_mtu = rt->rt_gwroute->rt_rmx.rmx_mtu;
501 			} else {
502 				rt->rt_rmx.rmx_mtu = ifa->ifa_ifp->if_mtu;
503 			}
504 		}
505 		if (ifa->ifa_rtrequest)
506 			ifa->ifa_rtrequest(req, rt, SA(ret_nrt ? *ret_nrt : 0));
507 		if (ret_nrt) {
508 			*ret_nrt = rt;
509 			rt->rt_refcnt++;
510 		}
511 		break;
512 	}
513 bad:
514 	splx(s);
515 	return (error);
516 }
517 
518 int
519 rt_setgate(rt0, dst, gate)
520 	struct rtentry *rt0;
521 	struct sockaddr *dst, *gate;
522 {
523 	caddr_t new, old;
524 	int dlen = ROUNDUP(dst->sa_len), glen = ROUNDUP(gate->sa_len);
525 	struct rtentry *rt = rt0;
526 
527 	if (rt->rt_gateway == 0 || glen > ROUNDUP(rt->rt_gateway->sa_len)) {
528 		old = (caddr_t)rt_key(rt);
529 		R_Malloc(new, caddr_t, dlen + glen);
530 		if (new == 0)
531 			return 1;
532 		Bzero(new, dlen + glen);
533 		rt->rt_nodes->rn_key = new;
534 	} else {
535 		new = rt->rt_nodes->rn_key;
536 		old = 0;
537 	}
538 	Bcopy(gate, (rt->rt_gateway = (struct sockaddr *)(new + dlen)), glen);
539 	if (old) {
540 		Bcopy(dst, new, dlen);
541 		Free(old);
542 	}
543 	if (rt->rt_gwroute) {
544 		rt = rt->rt_gwroute; RTFREE(rt);
545 		rt = rt0; rt->rt_gwroute = 0;
546 	}
547 	if (rt->rt_flags & RTF_GATEWAY) {
548 		rt->rt_gwroute = rtalloc1(gate, 1);
549 		/*
550 		 * If we switched gateways, grab the MTU from the new
551 		 * gateway route if the current MTU is 0 or greater
552 		 * than the MTU of gateway.
553 		 */
554 		if (rt->rt_gwroute
555 		    && !(rt->rt_rmx.rmx_locks & RTV_MTU)
556 		    && (rt->rt_rmx.rmx_mtu == 0
557 		    || rt->rt_rmx.rmx_mtu > rt->rt_gwroute->rt_rmx.rmx_mtu)) { /* XXX */
558 			rt->rt_rmx.rmx_mtu = rt->rt_gwroute->rt_rmx.rmx_mtu;
559 		}
560 	}
561 	return 0;
562 }
563 
564 void
565 rt_maskedcopy(src, dst, netmask)
566 	struct sockaddr *src, *dst, *netmask;
567 {
568 	u_char *cp1 = (u_char *)src;
569 	u_char *cp2 = (u_char *)dst;
570 	u_char *cp3 = (u_char *)netmask;
571 	u_char *cplim = cp2 + *cp3;
572 	u_char *cplim2 = cp2 + *cp1;
573 
574 	*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
575 	cp3 += 2;
576 	if (cplim > cplim2)
577 		cplim = cplim2;
578 	while (cp2 < cplim)
579 		*cp2++ = *cp1++ & *cp3++;
580 	if (cp2 < cplim2)
581 		bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2));
582 }
583 
584 /*
585  * Set up or tear down a routing table entry, normally
586  * for an interface.
587  */
588 int
589 rtinit(ifa, cmd, flags)
590 	struct ifaddr *ifa;
591 	int cmd, flags;
592 {
593 	struct rtentry *rt;
594 	struct sockaddr *dst, *odst;
595 	struct sockaddr_storage deldst;
596 	struct rtentry *nrt = 0;
597 	int error;
598 
599 	dst = flags & RTF_HOST ? ifa->ifa_dstaddr : ifa->ifa_addr;
600 	if (cmd == RTM_DELETE) {
601 		if ((flags & RTF_HOST) == 0 && ifa->ifa_netmask) {
602 			/* Delete subnet route for this interface */
603 			odst = dst;
604 			dst = (struct sockaddr *)&deldst;
605 			rt_maskedcopy(odst, dst, ifa->ifa_netmask);
606 		}
607 		if ((rt = rtalloc1(dst, 0)) != NULL) {
608 			rt->rt_refcnt--;
609 			if (rt->rt_ifa != ifa)
610 				return (flags & RTF_HOST ? EHOSTUNREACH
611 							: ENETUNREACH);
612 		}
613 	}
614 	error = rtrequest(cmd, dst, ifa->ifa_addr, ifa->ifa_netmask,
615 			flags | ifa->ifa_flags, &nrt);
616 	if (cmd == RTM_DELETE && error == 0 && (rt = nrt)) {
617 		rt_newaddrmsg(cmd, ifa, error, nrt);
618 		if (rt->rt_refcnt <= 0) {
619 			rt->rt_refcnt++;
620 			rtfree(rt);
621 		}
622 	}
623 	if (cmd == RTM_ADD && error == 0 && (rt = nrt)) {
624 		rt->rt_refcnt--;
625 		if (rt->rt_ifa != ifa) {
626 			printf("rtinit: wrong ifa (%p) was (%p)\n", ifa,
627 				rt->rt_ifa);
628 			if (rt->rt_ifa->ifa_rtrequest)
629 			    rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
630 			IFAFREE(rt->rt_ifa);
631 			rt->rt_ifa = ifa;
632 			rt->rt_ifp = ifa->ifa_ifp;
633 			rt->rt_rmx.rmx_mtu = ifa->ifa_ifp->if_mtu;	/*XXX*/
634 			IFAREF(ifa);
635 			if (ifa->ifa_rtrequest)
636 			    ifa->ifa_rtrequest(RTM_ADD, rt, SA(0));
637 		}
638 		rt_newaddrmsg(cmd, ifa, error, nrt);
639 	}
640 	return (error);
641 }
642 
643 /*
644  * Route timer routines.  These routes allow functions to be called
645  * for various routes at any time.  This is useful in supporting
646  * path MTU discovery and redirect route deletion.
647  *
648  * This is similar to some BSDI internal functions, but it provides
649  * for multiple queues for efficiency's sake...
650  */
651 
652 LIST_HEAD(, rttimer_queue) rttimer_queue_head;
653 static int rt_init_done = 0;
654 
655 #define RTTIMER_CALLOUT(r)	{				\
656 	if (r->rtt_func != NULL) {				\
657 		(*r->rtt_func)(r->rtt_rt, r);			\
658 	} else {						\
659 		rtrequest((int) RTM_DELETE,			\
660 			  (struct sockaddr *)rt_key(r->rtt_rt),	\
661 			  0, 0, 0, 0);				\
662 	}							\
663 }
664 
665 /*
666  * Some subtle order problems with domain initialization mean that
667  * we cannot count on this being run from rt_init before various
668  * protocol initializations are done.  Therefore, we make sure
669  * that this is run when the first queue is added...
670  */
671 
672 void
673 rt_timer_init()
674 {
675 	assert(rt_init_done == 0);
676 
677 	pool_init(&rttimer_pool, sizeof(struct rttimer), 0, 0, 0, "rttmrpl",
678 	    0, NULL, NULL, M_RTABLE);
679 
680 	LIST_INIT(&rttimer_queue_head);
681 	callout_init(&rt_timer_ch);
682 	callout_reset(&rt_timer_ch, hz, rt_timer_timer, NULL);
683 	rt_init_done = 1;
684 }
685 
686 struct rttimer_queue *
687 rt_timer_queue_create(timeout)
688 	u_int	timeout;
689 {
690 	struct rttimer_queue *rtq;
691 
692 	if (rt_init_done == 0)
693 		rt_timer_init();
694 
695 	R_Malloc(rtq, struct rttimer_queue *, sizeof *rtq);
696 	if (rtq == NULL)
697 		return (NULL);
698 	Bzero(rtq, sizeof *rtq);
699 
700 	rtq->rtq_timeout = timeout;
701 	TAILQ_INIT(&rtq->rtq_head);
702 	LIST_INSERT_HEAD(&rttimer_queue_head, rtq, rtq_link);
703 
704 	return (rtq);
705 }
706 
707 void
708 rt_timer_queue_change(rtq, timeout)
709 	struct rttimer_queue *rtq;
710 	long timeout;
711 {
712 
713 	rtq->rtq_timeout = timeout;
714 }
715 
716 
717 void
718 rt_timer_queue_destroy(rtq, destroy)
719 	struct rttimer_queue *rtq;
720 	int destroy;
721 {
722 	struct rttimer *r;
723 
724 	while ((r = TAILQ_FIRST(&rtq->rtq_head)) != NULL) {
725 		LIST_REMOVE(r, rtt_link);
726 		TAILQ_REMOVE(&rtq->rtq_head, r, rtt_next);
727 		if (destroy)
728 			RTTIMER_CALLOUT(r);
729 		pool_put(&rttimer_pool, r);
730 	}
731 
732 	LIST_REMOVE(rtq, rtq_link);
733 
734 	/*
735 	 * Caller is responsible for freeing the rttimer_queue structure.
736 	 */
737 }
738 
739 void
740 rt_timer_remove_all(rt)
741 	struct rtentry *rt;
742 {
743 	struct rttimer *r;
744 
745 	while ((r = LIST_FIRST(&rt->rt_timer)) != NULL) {
746 		LIST_REMOVE(r, rtt_link);
747 		TAILQ_REMOVE(&r->rtt_queue->rtq_head, r, rtt_next);
748 		pool_put(&rttimer_pool, r);
749 	}
750 }
751 
752 int
753 rt_timer_add(rt, func, queue)
754 	struct rtentry *rt;
755 	void(*func) __P((struct rtentry *, struct rttimer *));
756 	struct rttimer_queue *queue;
757 {
758 	struct rttimer *r;
759 	long current_time;
760 	int s;
761 
762 	s = splclock();
763 	current_time = mono_time.tv_sec;
764 	splx(s);
765 
766 	/*
767 	 * If there's already a timer with this action, destroy it before
768 	 * we add a new one.
769 	 */
770 	for (r = LIST_FIRST(&rt->rt_timer); r != NULL;
771 	     r = LIST_NEXT(r, rtt_link)) {
772 		if (r->rtt_func == func) {
773 			LIST_REMOVE(r, rtt_link);
774 			TAILQ_REMOVE(&r->rtt_queue->rtq_head, r, rtt_next);
775 			pool_put(&rttimer_pool, r);
776 			break;  /* only one per list, so we can quit... */
777 		}
778 	}
779 
780 	r = pool_get(&rttimer_pool, PR_NOWAIT);
781 	if (r == NULL)
782 		return (ENOBUFS);
783 	Bzero(r, sizeof(*r));
784 
785 	r->rtt_rt = rt;
786 	r->rtt_time = current_time;
787 	r->rtt_func = func;
788 	r->rtt_queue = queue;
789 	LIST_INSERT_HEAD(&rt->rt_timer, r, rtt_link);
790 	TAILQ_INSERT_TAIL(&queue->rtq_head, r, rtt_next);
791 
792 	return (0);
793 }
794 
795 /* ARGSUSED */
796 void
797 rt_timer_timer(arg)
798 	void *arg;
799 {
800 	struct rttimer_queue *rtq;
801 	struct rttimer *r;
802 	long current_time;
803 	int s;
804 
805 	s = splclock();
806 	current_time = mono_time.tv_sec;
807 	splx(s);
808 
809 	s = splsoftnet();
810 	for (rtq = LIST_FIRST(&rttimer_queue_head); rtq != NULL;
811 	     rtq = LIST_NEXT(rtq, rtq_link)) {
812 		while ((r = TAILQ_FIRST(&rtq->rtq_head)) != NULL &&
813 		    (r->rtt_time + rtq->rtq_timeout) < current_time) {
814 			LIST_REMOVE(r, rtt_link);
815 			TAILQ_REMOVE(&rtq->rtq_head, r, rtt_next);
816 			RTTIMER_CALLOUT(r);
817 			pool_put(&rttimer_pool, r);
818 		}
819 	}
820 	splx(s);
821 
822 	callout_reset(&rt_timer_ch, hz, rt_timer_timer, NULL);
823 }
824