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route.c revision 1.72
      1 /*	$NetBSD: route.c,v 1.72 2006/10/05 17:35:19 tls 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. Neither the name of the University nor the names of its contributors
     82  *    may be used to endorse or promote products derived from this software
     83  *    without specific prior written permission.
     84  *
     85  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     86  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     87  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     88  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     89  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     90  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     91  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     92  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     93  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     94  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     95  * SUCH DAMAGE.
     96  *
     97  *	@(#)route.c	8.3 (Berkeley) 1/9/95
     98  */
     99 
    100 #include <sys/cdefs.h>
    101 __KERNEL_RCSID(0, "$NetBSD: route.c,v 1.72 2006/10/05 17:35:19 tls Exp $");
    102 
    103 
    104 #include <sys/param.h>
    105 #include <sys/systm.h>
    106 #include <sys/callout.h>
    107 #include <sys/proc.h>
    108 #include <sys/mbuf.h>
    109 #include <sys/socket.h>
    110 #include <sys/socketvar.h>
    111 #include <sys/domain.h>
    112 #include <sys/protosw.h>
    113 #include <sys/kernel.h>
    114 #include <sys/ioctl.h>
    115 #include <sys/pool.h>
    116 
    117 #include <net/if.h>
    118 #include <net/route.h>
    119 #include <net/raw_cb.h>
    120 
    121 #include <netinet/in.h>
    122 #include <netinet/in_var.h>
    123 
    124 
    125 struct	route_cb route_cb;
    126 struct	rtstat	rtstat;
    127 struct	radix_node_head *rt_tables[AF_MAX+1];
    128 
    129 int	rttrash;		/* routes not in table but not freed */
    130 struct	sockaddr wildcard;	/* zero valued cookie for wildcard searches */
    131 
    132 POOL_INIT(rtentry_pool, sizeof(struct rtentry), 0, 0, 0, "rtentpl", NULL);
    133 POOL_INIT(rttimer_pool, sizeof(struct rttimer), 0, 0, 0, "rttmrpl", NULL);
    134 
    135 struct callout rt_timer_ch; /* callout for rt_timer_timer() */
    136 
    137 static int rtdeletemsg(struct rtentry *);
    138 static int rtflushclone1(struct radix_node *, void *);
    139 static void rtflushclone(struct radix_node_head *, struct rtentry *);
    140 
    141 void
    142 rtable_init(void **table)
    143 {
    144 	struct domain *dom;
    145 	DOMAIN_FOREACH(dom)
    146 		if (dom->dom_rtattach)
    147 			dom->dom_rtattach(&table[dom->dom_family],
    148 			    dom->dom_rtoffset);
    149 }
    150 
    151 void
    152 route_init(void)
    153 {
    154 
    155 	rn_init();	/* initialize all zeroes, all ones, mask table */
    156 	rtable_init((void **)rt_tables);
    157 }
    158 
    159 /*
    160  * Packet routing routines.
    161  */
    162 void
    163 rtalloc(struct route *ro)
    164 {
    165 	if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
    166 		return;				 /* XXX */
    167 	ro->ro_rt = rtalloc1(&ro->ro_dst, 1);
    168 }
    169 
    170 struct rtentry *
    171 rtalloc1(const struct sockaddr *dst, int report)
    172 {
    173 	struct radix_node_head *rnh = rt_tables[dst->sa_family];
    174 	struct rtentry *rt;
    175 	struct radix_node *rn;
    176 	struct rtentry *newrt = NULL;
    177 	struct rt_addrinfo info;
    178 	int  s = splsoftnet(), err = 0, msgtype = RTM_MISS;
    179 
    180 	if (rnh && (rn = rnh->rnh_matchaddr(dst, rnh)) &&
    181 	    ((rn->rn_flags & RNF_ROOT) == 0)) {
    182 		newrt = rt = (struct rtentry *)rn;
    183 		if (report && (rt->rt_flags & RTF_CLONING)) {
    184 			err = rtrequest(RTM_RESOLVE, dst, NULL, NULL, 0,
    185 			    &newrt);
    186 			if (err) {
    187 				newrt = rt;
    188 				rt->rt_refcnt++;
    189 				goto miss;
    190 			}
    191 			KASSERT(newrt != NULL);
    192 			if ((rt = newrt) && (rt->rt_flags & RTF_XRESOLVE)) {
    193 				msgtype = RTM_RESOLVE;
    194 				goto miss;
    195 			}
    196 			/* Inform listeners of the new route */
    197 			memset(&info, 0, sizeof(info));
    198 			info.rti_info[RTAX_DST] = rt_key(rt);
    199 			info.rti_info[RTAX_NETMASK] = rt_mask(rt);
    200 			info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
    201 			if (rt->rt_ifp != NULL) {
    202 				info.rti_info[RTAX_IFP] =
    203 				    TAILQ_FIRST(&rt->rt_ifp->if_addrlist)->ifa_addr;
    204 				info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr;
    205 			}
    206 			rt_missmsg(RTM_ADD, &info, rt->rt_flags, 0);
    207 		} else
    208 			rt->rt_refcnt++;
    209 	} else {
    210 		rtstat.rts_unreach++;
    211 	miss:	if (report) {
    212 			memset((caddr_t)&info, 0, sizeof(info));
    213 			info.rti_info[RTAX_DST] = dst;
    214 			rt_missmsg(msgtype, &info, 0, err);
    215 		}
    216 	}
    217 	splx(s);
    218 	return (newrt);
    219 }
    220 
    221 void
    222 rtfree(struct rtentry *rt)
    223 {
    224 	struct ifaddr *ifa;
    225 
    226 	if (rt == NULL)
    227 		panic("rtfree");
    228 	rt->rt_refcnt--;
    229 	if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_UP) == 0) {
    230 		if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT))
    231 			panic ("rtfree 2");
    232 		rttrash--;
    233 		if (rt->rt_refcnt < 0) {
    234 			printf("rtfree: %p not freed (neg refs)\n", rt);
    235 			return;
    236 		}
    237 		rt_timer_remove_all(rt, 0);
    238 		ifa = rt->rt_ifa;
    239 		IFAFREE(ifa);
    240 		Free(rt_key(rt));
    241 		pool_put(&rtentry_pool, rt);
    242 	}
    243 }
    244 
    245 void
    246 ifafree(struct ifaddr *ifa)
    247 {
    248 
    249 #ifdef DIAGNOSTIC
    250 	if (ifa == NULL)
    251 		panic("ifafree: null ifa");
    252 	if (ifa->ifa_refcnt != 0)
    253 		panic("ifafree: ifa_refcnt != 0 (%d)", ifa->ifa_refcnt);
    254 #endif
    255 #ifdef IFAREF_DEBUG
    256 	printf("ifafree: freeing ifaddr %p\n", ifa);
    257 #endif
    258 	free(ifa, M_IFADDR);
    259 }
    260 
    261 /*
    262  * Force a routing table entry to the specified
    263  * destination to go through the given gateway.
    264  * Normally called as a result of a routing redirect
    265  * message from the network layer.
    266  *
    267  * N.B.: must be called at splsoftnet
    268  */
    269 void
    270 rtredirect(const struct sockaddr *dst, const struct sockaddr *gateway,
    271 	const struct sockaddr *netmask, int flags, const struct sockaddr *src,
    272 	struct rtentry **rtp)
    273 {
    274 	struct rtentry *rt;
    275 	int error = 0;
    276 	u_quad_t *stat = NULL;
    277 	struct rt_addrinfo info;
    278 	struct ifaddr *ifa;
    279 
    280 	/* verify the gateway is directly reachable */
    281 	if ((ifa = ifa_ifwithnet(gateway)) == NULL) {
    282 		error = ENETUNREACH;
    283 		goto out;
    284 	}
    285 	rt = rtalloc1(dst, 0);
    286 	/*
    287 	 * If the redirect isn't from our current router for this dst,
    288 	 * it's either old or wrong.  If it redirects us to ourselves,
    289 	 * we have a routing loop, perhaps as a result of an interface
    290 	 * going down recently.
    291 	 */
    292 #define	equal(a1, a2) \
    293 	((a1)->sa_len == (a2)->sa_len && \
    294 	 memcmp((a1), (a2), (a1)->sa_len) == 0)
    295 	if (!(flags & RTF_DONE) && rt &&
    296 	     (!equal(src, rt->rt_gateway) || rt->rt_ifa != ifa))
    297 		error = EINVAL;
    298 	else if (ifa_ifwithaddr(gateway))
    299 		error = EHOSTUNREACH;
    300 	if (error)
    301 		goto done;
    302 	/*
    303 	 * Create a new entry if we just got back a wildcard entry
    304 	 * or the lookup failed.  This is necessary for hosts
    305 	 * which use routing redirects generated by smart gateways
    306 	 * to dynamically build the routing tables.
    307 	 */
    308 	if ((rt == NULL) || (rt_mask(rt) && rt_mask(rt)->sa_len < 2))
    309 		goto create;
    310 	/*
    311 	 * Don't listen to the redirect if it's
    312 	 * for a route to an interface.
    313 	 */
    314 	if (rt->rt_flags & RTF_GATEWAY) {
    315 		if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) {
    316 			/*
    317 			 * Changing from route to net => route to host.
    318 			 * Create new route, rather than smashing route to net.
    319 			 */
    320 		create:
    321 			if (rt)
    322 				rtfree(rt);
    323 			flags |=  RTF_GATEWAY | RTF_DYNAMIC;
    324 			info.rti_info[RTAX_DST] = dst;
    325 			info.rti_info[RTAX_GATEWAY] = gateway;
    326 			info.rti_info[RTAX_NETMASK] = netmask;
    327 			info.rti_ifa = ifa;
    328 			info.rti_flags = flags;
    329 			rt = NULL;
    330 			error = rtrequest1(RTM_ADD, &info, &rt);
    331 			if (rt != NULL)
    332 				flags = rt->rt_flags;
    333 			stat = &rtstat.rts_dynamic;
    334 		} else {
    335 			/*
    336 			 * Smash the current notion of the gateway to
    337 			 * this destination.  Should check about netmask!!!
    338 			 */
    339 			rt->rt_flags |= RTF_MODIFIED;
    340 			flags |= RTF_MODIFIED;
    341 			stat = &rtstat.rts_newgateway;
    342 			rt_setgate(rt, rt_key(rt), gateway);
    343 		}
    344 	} else
    345 		error = EHOSTUNREACH;
    346 done:
    347 	if (rt) {
    348 		if (rtp && !error)
    349 			*rtp = rt;
    350 		else
    351 			rtfree(rt);
    352 	}
    353 out:
    354 	if (error)
    355 		rtstat.rts_badredirect++;
    356 	else if (stat != NULL)
    357 		(*stat)++;
    358 	memset((caddr_t)&info, 0, sizeof(info));
    359 	info.rti_info[RTAX_DST] = dst;
    360 	info.rti_info[RTAX_GATEWAY] = gateway;
    361 	info.rti_info[RTAX_NETMASK] = netmask;
    362 	info.rti_info[RTAX_AUTHOR] = src;
    363 	rt_missmsg(RTM_REDIRECT, &info, flags, error);
    364 }
    365 
    366 /*
    367  * Delete a route and generate a message
    368  */
    369 static int
    370 rtdeletemsg(struct rtentry *rt)
    371 {
    372 	int error;
    373 	struct rt_addrinfo info;
    374 
    375 	/*
    376 	 * Request the new route so that the entry is not actually
    377 	 * deleted.  That will allow the information being reported to
    378 	 * be accurate (and consistent with route_output()).
    379 	 */
    380 	memset((caddr_t)&info, 0, sizeof(info));
    381 	info.rti_info[RTAX_DST] = rt_key(rt);
    382 	info.rti_info[RTAX_NETMASK] = rt_mask(rt);
    383 	info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
    384 	info.rti_flags = rt->rt_flags;
    385 	error = rtrequest1(RTM_DELETE, &info, &rt);
    386 
    387 	rt_missmsg(RTM_DELETE, &info, info.rti_flags, error);
    388 
    389 	/* Adjust the refcount */
    390 	if (error == 0 && rt->rt_refcnt <= 0) {
    391 		rt->rt_refcnt++;
    392 		rtfree(rt);
    393 	}
    394 	return (error);
    395 }
    396 
    397 static int
    398 rtflushclone1(struct radix_node *rn, void *arg)
    399 {
    400 	struct rtentry *rt, *parent;
    401 
    402 	rt = (struct rtentry *)rn;
    403 	parent = (struct rtentry *)arg;
    404 	if ((rt->rt_flags & RTF_CLONED) != 0 && rt->rt_parent == parent)
    405 		rtdeletemsg(rt);
    406 	return 0;
    407 }
    408 
    409 static void
    410 rtflushclone(struct radix_node_head *rnh, struct rtentry *parent)
    411 {
    412 
    413 #ifdef DIAGNOSTIC
    414 	if (!parent || (parent->rt_flags & RTF_CLONING) == 0)
    415 		panic("rtflushclone: called with a non-cloning route");
    416 	if (!rnh->rnh_walktree)
    417 		panic("rtflushclone: no rnh_walktree");
    418 #endif
    419 	rnh->rnh_walktree(rnh, rtflushclone1, (void *)parent);
    420 }
    421 
    422 /*
    423  * Routing table ioctl interface.
    424  */
    425 int
    426 rtioctl(u_long req, caddr_t data, struct lwp *l)
    427 {
    428 	return (EOPNOTSUPP);
    429 }
    430 
    431 struct ifaddr *
    432 ifa_ifwithroute(int flags, const struct sockaddr *dst,
    433 	const struct sockaddr *gateway)
    434 {
    435 	struct ifaddr *ifa;
    436 	if ((flags & RTF_GATEWAY) == 0) {
    437 		/*
    438 		 * If we are adding a route to an interface,
    439 		 * and the interface is a pt to pt link
    440 		 * we should search for the destination
    441 		 * as our clue to the interface.  Otherwise
    442 		 * we can use the local address.
    443 		 */
    444 		ifa = NULL;
    445 		if (flags & RTF_HOST)
    446 			ifa = ifa_ifwithdstaddr(dst);
    447 		if (ifa == NULL)
    448 			ifa = ifa_ifwithaddr(gateway);
    449 	} else {
    450 		/*
    451 		 * If we are adding a route to a remote net
    452 		 * or host, the gateway may still be on the
    453 		 * other end of a pt to pt link.
    454 		 */
    455 		ifa = ifa_ifwithdstaddr(gateway);
    456 	}
    457 	if (ifa == NULL)
    458 		ifa = ifa_ifwithnet(gateway);
    459 	if (ifa == NULL) {
    460 		struct rtentry *rt = rtalloc1(dst, 0);
    461 		if (rt == NULL)
    462 			return NULL;
    463 		rt->rt_refcnt--;
    464 		if ((ifa = rt->rt_ifa) == NULL)
    465 			return NULL;
    466 	}
    467 	if (ifa->ifa_addr->sa_family != dst->sa_family) {
    468 		struct ifaddr *oifa = ifa;
    469 		ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
    470 		if (ifa == 0)
    471 			ifa = oifa;
    472 	}
    473 	return (ifa);
    474 }
    475 
    476 #define ROUNDUP(a) (a>0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
    477 
    478 int
    479 rtrequest(int req, const struct sockaddr *dst, const struct sockaddr *gateway,
    480 	const struct sockaddr *netmask, int flags, struct rtentry **ret_nrt)
    481 {
    482 	struct rt_addrinfo info;
    483 
    484 	memset(&info, 0, sizeof(info));
    485 	info.rti_flags = flags;
    486 	info.rti_info[RTAX_DST] = dst;
    487 	info.rti_info[RTAX_GATEWAY] = gateway;
    488 	info.rti_info[RTAX_NETMASK] = netmask;
    489 	return rtrequest1(req, &info, ret_nrt);
    490 }
    491 
    492 int
    493 rt_getifa(struct rt_addrinfo *info)
    494 {
    495 	struct ifaddr *ifa;
    496 	int error = 0;
    497 	const struct sockaddr *dst = info->rti_info[RTAX_DST];
    498 	const struct sockaddr *gateway = info->rti_info[RTAX_GATEWAY];
    499 	const struct sockaddr *ifaaddr = info->rti_info[RTAX_IFA];
    500 	const struct sockaddr *ifpaddr = info->rti_info[RTAX_IFP];
    501 	int flags = info->rti_flags;
    502 
    503 	/*
    504 	 * ifp may be specified by sockaddr_dl when protocol address
    505 	 * is ambiguous
    506 	 */
    507 	if (info->rti_ifp == NULL && ifpaddr != NULL
    508 	    && ifpaddr->sa_family == AF_LINK &&
    509 	    (ifa = ifa_ifwithnet((const struct sockaddr *)ifpaddr)) != NULL)
    510 		info->rti_ifp = ifa->ifa_ifp;
    511 	if (info->rti_ifa == NULL && ifaaddr != NULL)
    512 		info->rti_ifa = ifa_ifwithaddr(ifaaddr);
    513 	if (info->rti_ifa == NULL) {
    514 		const struct sockaddr *sa;
    515 
    516 		sa = ifaaddr != NULL ? ifaaddr :
    517 		    (gateway != NULL ? gateway : dst);
    518 		if (sa != NULL && info->rti_ifp != NULL)
    519 			info->rti_ifa = ifaof_ifpforaddr(sa, info->rti_ifp);
    520 		else if (dst != NULL && gateway != NULL)
    521 			info->rti_ifa = ifa_ifwithroute(flags, dst, gateway);
    522 		else if (sa != NULL)
    523 			info->rti_ifa = ifa_ifwithroute(flags, sa, sa);
    524 	}
    525 	if ((ifa = info->rti_ifa) != NULL) {
    526 		if (info->rti_ifp == NULL)
    527 			info->rti_ifp = ifa->ifa_ifp;
    528 	} else
    529 		error = ENETUNREACH;
    530 	return (error);
    531 }
    532 
    533 int
    534 rtrequest1(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt)
    535 {
    536 	int s = splsoftnet();
    537 	int error = 0;
    538 	struct rtentry *rt, *crt;
    539 	struct radix_node *rn;
    540 	struct radix_node_head *rnh;
    541 	struct ifaddr *ifa;
    542 	struct sockaddr *ndst;
    543 	struct sockaddr_storage deldst;
    544 	const struct sockaddr *dst = info->rti_info[RTAX_DST];
    545 	const struct sockaddr *gateway = info->rti_info[RTAX_GATEWAY];
    546 	const struct sockaddr *netmask = info->rti_info[RTAX_NETMASK];
    547 	int flags = info->rti_flags;
    548 #define senderr(x) { error = x ; goto bad; }
    549 
    550 	if ((rnh = rt_tables[dst->sa_family]) == NULL)
    551 		senderr(ESRCH);
    552 	if (flags & RTF_HOST)
    553 		netmask = NULL;
    554 	switch (req) {
    555 	case RTM_DELETE:
    556 		if (netmask) {
    557 			rt_maskedcopy(dst, (struct sockaddr *)&deldst, netmask);
    558 			dst = (struct sockaddr *)&deldst;
    559 		}
    560 		if ((rn = rnh->rnh_lookup(dst, netmask, rnh)) == NULL)
    561 			senderr(ESRCH);
    562 		rt = (struct rtentry *)rn;
    563 		if ((rt->rt_flags & RTF_CLONING) != 0) {
    564 			/* clean up any cloned children */
    565 			rtflushclone(rnh, rt);
    566 		}
    567 		if ((rn = rnh->rnh_deladdr(dst, netmask, rnh)) == NULL)
    568 			senderr(ESRCH);
    569 		if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT))
    570 			panic ("rtrequest delete");
    571 		rt = (struct rtentry *)rn;
    572 		if (rt->rt_gwroute) {
    573 			RTFREE(rt->rt_gwroute);
    574 			rt->rt_gwroute = NULL;
    575 		}
    576 		if (rt->rt_parent) {
    577 			rt->rt_parent->rt_refcnt--;
    578 			rt->rt_parent = NULL;
    579 		}
    580 		rt->rt_flags &= ~RTF_UP;
    581 		if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
    582 			ifa->ifa_rtrequest(RTM_DELETE, rt, info);
    583 		rttrash++;
    584 		if (ret_nrt)
    585 			*ret_nrt = rt;
    586 		else if (rt->rt_refcnt <= 0) {
    587 			rt->rt_refcnt++;
    588 			rtfree(rt);
    589 		}
    590 		break;
    591 
    592 	case RTM_RESOLVE:
    593 		if (ret_nrt == NULL || (rt = *ret_nrt) == NULL)
    594 			senderr(EINVAL);
    595 		if ((rt->rt_flags & RTF_CLONING) == 0)
    596 			senderr(EINVAL);
    597 		ifa = rt->rt_ifa;
    598 		flags = rt->rt_flags & ~(RTF_CLONING | RTF_STATIC);
    599 		flags |= RTF_CLONED;
    600 		gateway = rt->rt_gateway;
    601 		if ((netmask = rt->rt_genmask) == NULL)
    602 			flags |= RTF_HOST;
    603 		goto makeroute;
    604 
    605 	case RTM_ADD:
    606 		if (info->rti_ifa == NULL && (error = rt_getifa(info)))
    607 			senderr(error);
    608 		ifa = info->rti_ifa;
    609 	makeroute:
    610 		/* Already at splsoftnet() so pool_get/pool_put are safe */
    611 		rt = pool_get(&rtentry_pool, PR_NOWAIT);
    612 		if (rt == NULL)
    613 			senderr(ENOBUFS);
    614 		Bzero(rt, sizeof(*rt));
    615 		rt->rt_flags = RTF_UP | flags;
    616 		LIST_INIT(&rt->rt_timer);
    617 		if (rt_setgate(rt, dst, gateway)) {
    618 			pool_put(&rtentry_pool, rt);
    619 			senderr(ENOBUFS);
    620 		}
    621 		ndst = rt_key(rt);
    622 		if (netmask) {
    623 			rt_maskedcopy(dst, ndst, netmask);
    624 		} else
    625 			Bcopy(dst, ndst, dst->sa_len);
    626 		IFAREF(ifa);
    627 		rt->rt_ifa = ifa;
    628 		rt->rt_ifp = ifa->ifa_ifp;
    629 		if (req == RTM_RESOLVE) {
    630 			rt->rt_rmx = (*ret_nrt)->rt_rmx; /* copy metrics */
    631 			rt->rt_parent = *ret_nrt;
    632 			rt->rt_parent->rt_refcnt++;
    633 		}
    634 		rn = rnh->rnh_addaddr(ndst, netmask, rnh, rt->rt_nodes);
    635 		if (rn == NULL && (crt = rtalloc1(ndst, 0)) != NULL) {
    636 			/* overwrite cloned route */
    637 			if ((crt->rt_flags & RTF_CLONED) != 0) {
    638 				rtdeletemsg(crt);
    639 				rn = rnh->rnh_addaddr(ndst,
    640 				    netmask, rnh, rt->rt_nodes);
    641 			}
    642 			RTFREE(crt);
    643 		}
    644 		if (rn == NULL) {
    645 			IFAFREE(ifa);
    646 			if ((rt->rt_flags & RTF_CLONED) != 0 && rt->rt_parent)
    647 				rtfree(rt->rt_parent);
    648 			if (rt->rt_gwroute)
    649 				rtfree(rt->rt_gwroute);
    650 			Free(rt_key(rt));
    651 			pool_put(&rtentry_pool, rt);
    652 			senderr(EEXIST);
    653 		}
    654 		if (ifa->ifa_rtrequest)
    655 			ifa->ifa_rtrequest(req, rt, info);
    656 		if (ret_nrt) {
    657 			*ret_nrt = rt;
    658 			rt->rt_refcnt++;
    659 		}
    660 		if ((rt->rt_flags & RTF_CLONING) != 0) {
    661 			/* clean up any cloned children */
    662 			rtflushclone(rnh, rt);
    663 		}
    664 		break;
    665 	}
    666 bad:
    667 	splx(s);
    668 	return (error);
    669 }
    670 
    671 int
    672 rt_setgate( struct rtentry *rt0, const struct sockaddr *dst,
    673 	const struct sockaddr *gate)
    674 {
    675 	char *new, *old;
    676 	u_int dlen = ROUNDUP(dst->sa_len), glen = ROUNDUP(gate->sa_len);
    677 	struct rtentry *rt = rt0;
    678 
    679 	if (rt->rt_gateway == NULL || glen > ROUNDUP(rt->rt_gateway->sa_len)) {
    680 		old = (caddr_t)rt_key(rt);
    681 		R_Malloc(new, caddr_t, dlen + glen);
    682 		if (new == NULL)
    683 			return 1;
    684 		Bzero(new, dlen + glen);
    685 		rt->rt_nodes->rn_key = new;
    686 	} else {
    687 		new = __UNCONST(rt->rt_nodes->rn_key); /*XXXUNCONST*/
    688 		old = NULL;
    689 	}
    690 	Bcopy(gate, (rt->rt_gateway = (struct sockaddr *)(new + dlen)), glen);
    691 	if (old) {
    692 		Bcopy(dst, new, dlen);
    693 		Free(old);
    694 	}
    695 	if (rt->rt_gwroute) {
    696 		RTFREE(rt->rt_gwroute);
    697 		rt->rt_gwroute = NULL;
    698 	}
    699 	if (rt->rt_flags & RTF_GATEWAY) {
    700 		rt->rt_gwroute = rtalloc1(gate, 1);
    701 		/*
    702 		 * If we switched gateways, grab the MTU from the new
    703 		 * gateway route if the current MTU, if the current MTU is
    704 		 * greater than the MTU of gateway.
    705 		 * Note that, if the MTU of gateway is 0, we will reset the
    706 		 * MTU of the route to run PMTUD again from scratch. XXX
    707 		 */
    708 		if (rt->rt_gwroute
    709 		    && !(rt->rt_rmx.rmx_locks & RTV_MTU)
    710 		    && rt->rt_rmx.rmx_mtu
    711 		    && rt->rt_rmx.rmx_mtu > rt->rt_gwroute->rt_rmx.rmx_mtu) {
    712 			rt->rt_rmx.rmx_mtu = rt->rt_gwroute->rt_rmx.rmx_mtu;
    713 		}
    714 	}
    715 	return 0;
    716 }
    717 
    718 void
    719 rt_maskedcopy(const struct sockaddr *src, struct sockaddr *dst,
    720 	const struct sockaddr *netmask)
    721 {
    722 	const u_char *cp1 = (const u_char *)src;
    723 	u_char *cp2 = (u_char *)dst;
    724 	const u_char *cp3 = (const u_char *)netmask;
    725 	u_char *cplim = cp2 + *cp3;
    726 	u_char *cplim2 = cp2 + *cp1;
    727 
    728 	*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
    729 	cp3 += 2;
    730 	if (cplim > cplim2)
    731 		cplim = cplim2;
    732 	while (cp2 < cplim)
    733 		*cp2++ = *cp1++ & *cp3++;
    734 	if (cp2 < cplim2)
    735 		memset(cp2, 0, (unsigned)(cplim2 - cp2));
    736 }
    737 
    738 /*
    739  * Set up or tear down a routing table entry, normally
    740  * for an interface.
    741  */
    742 int
    743 rtinit(struct ifaddr *ifa, int cmd, int flags)
    744 {
    745 	struct rtentry *rt;
    746 	struct sockaddr *dst, *odst;
    747 	struct sockaddr_storage deldst;
    748 	struct rtentry *nrt = NULL;
    749 	int error;
    750 	struct rt_addrinfo info;
    751 
    752 	dst = flags & RTF_HOST ? ifa->ifa_dstaddr : ifa->ifa_addr;
    753 	if (cmd == RTM_DELETE) {
    754 		if ((flags & RTF_HOST) == 0 && ifa->ifa_netmask) {
    755 			/* Delete subnet route for this interface */
    756 			odst = dst;
    757 			dst = (struct sockaddr *)&deldst;
    758 			rt_maskedcopy(odst, dst, ifa->ifa_netmask);
    759 		}
    760 		if ((rt = rtalloc1(dst, 0)) != NULL) {
    761 			rt->rt_refcnt--;
    762 			if (rt->rt_ifa != ifa)
    763 				return (flags & RTF_HOST ? EHOSTUNREACH
    764 							: ENETUNREACH);
    765 		}
    766 	}
    767 	memset(&info, 0, sizeof(info));
    768 	info.rti_ifa = ifa;
    769 	info.rti_flags = flags | ifa->ifa_flags;
    770 	info.rti_info[RTAX_DST] = dst;
    771 	info.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
    772 	/*
    773 	 * XXX here, it seems that we are assuming that ifa_netmask is NULL
    774 	 * for RTF_HOST.  bsdi4 passes NULL explicitly (via intermediate
    775 	 * variable) when RTF_HOST is 1.  still not sure if i can safely
    776 	 * change it to meet bsdi4 behavior.
    777 	 */
    778 	info.rti_info[RTAX_NETMASK] = ifa->ifa_netmask;
    779 	error = rtrequest1(cmd, &info, &nrt);
    780 	if (cmd == RTM_DELETE && error == 0 && (rt = nrt)) {
    781 		rt_newaddrmsg(cmd, ifa, error, nrt);
    782 		if (rt->rt_refcnt <= 0) {
    783 			rt->rt_refcnt++;
    784 			rtfree(rt);
    785 		}
    786 	}
    787 	if (cmd == RTM_ADD && error == 0 && (rt = nrt)) {
    788 		rt->rt_refcnt--;
    789 		if (rt->rt_ifa != ifa) {
    790 			printf("rtinit: wrong ifa (%p) was (%p)\n", ifa,
    791 				rt->rt_ifa);
    792 			if (rt->rt_ifa->ifa_rtrequest)
    793 				rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt, NULL);
    794 			IFAFREE(rt->rt_ifa);
    795 			rt->rt_ifa = ifa;
    796 			rt->rt_ifp = ifa->ifa_ifp;
    797 			IFAREF(ifa);
    798 			if (ifa->ifa_rtrequest)
    799 				ifa->ifa_rtrequest(RTM_ADD, rt, NULL);
    800 		}
    801 		rt_newaddrmsg(cmd, ifa, error, nrt);
    802 	}
    803 	return (error);
    804 }
    805 
    806 /*
    807  * Route timer routines.  These routes allow functions to be called
    808  * for various routes at any time.  This is useful in supporting
    809  * path MTU discovery and redirect route deletion.
    810  *
    811  * This is similar to some BSDI internal functions, but it provides
    812  * for multiple queues for efficiency's sake...
    813  */
    814 
    815 LIST_HEAD(, rttimer_queue) rttimer_queue_head;
    816 static int rt_init_done = 0;
    817 
    818 #define RTTIMER_CALLOUT(r)	do {					\
    819 		if (r->rtt_func != NULL) {				\
    820 			(*r->rtt_func)(r->rtt_rt, r);			\
    821 		} else {						\
    822 			rtrequest((int) RTM_DELETE,			\
    823 				  (struct sockaddr *)rt_key(r->rtt_rt),	\
    824 				  0, 0, 0, 0);				\
    825 		}							\
    826 	} while (/*CONSTCOND*/0)
    827 
    828 /*
    829  * Some subtle order problems with domain initialization mean that
    830  * we cannot count on this being run from rt_init before various
    831  * protocol initializations are done.  Therefore, we make sure
    832  * that this is run when the first queue is added...
    833  */
    834 
    835 void
    836 rt_timer_init(void)
    837 {
    838 	assert(rt_init_done == 0);
    839 
    840 	LIST_INIT(&rttimer_queue_head);
    841 	callout_init(&rt_timer_ch);
    842 	callout_reset(&rt_timer_ch, hz, rt_timer_timer, NULL);
    843 	rt_init_done = 1;
    844 }
    845 
    846 struct rttimer_queue *
    847 rt_timer_queue_create(u_int timeout)
    848 {
    849 	struct rttimer_queue *rtq;
    850 
    851 	if (rt_init_done == 0)
    852 		rt_timer_init();
    853 
    854 	R_Malloc(rtq, struct rttimer_queue *, sizeof *rtq);
    855 	if (rtq == NULL)
    856 		return (NULL);
    857 	Bzero(rtq, sizeof *rtq);
    858 
    859 	rtq->rtq_timeout = timeout;
    860 	rtq->rtq_count = 0;
    861 	TAILQ_INIT(&rtq->rtq_head);
    862 	LIST_INSERT_HEAD(&rttimer_queue_head, rtq, rtq_link);
    863 
    864 	return (rtq);
    865 }
    866 
    867 void
    868 rt_timer_queue_change(struct rttimer_queue *rtq, long timeout)
    869 {
    870 
    871 	rtq->rtq_timeout = timeout;
    872 }
    873 
    874 void
    875 rt_timer_queue_remove_all(struct rttimer_queue *rtq, int destroy)
    876 {
    877 	struct rttimer *r;
    878 
    879 	while ((r = TAILQ_FIRST(&rtq->rtq_head)) != NULL) {
    880 		LIST_REMOVE(r, rtt_link);
    881 		TAILQ_REMOVE(&rtq->rtq_head, r, rtt_next);
    882 		if (destroy)
    883 			RTTIMER_CALLOUT(r);
    884 		/* we are already at splsoftnet */
    885 		pool_put(&rttimer_pool, r);
    886 		if (rtq->rtq_count > 0)
    887 			rtq->rtq_count--;
    888 		else
    889 			printf("rt_timer_queue_remove_all: "
    890 			    "rtq_count reached 0\n");
    891 	}
    892 }
    893 
    894 void
    895 rt_timer_queue_destroy(struct rttimer_queue *rtq, int destroy)
    896 {
    897 
    898 	rt_timer_queue_remove_all(rtq, destroy);
    899 
    900 	LIST_REMOVE(rtq, rtq_link);
    901 
    902 	/*
    903 	 * Caller is responsible for freeing the rttimer_queue structure.
    904 	 */
    905 }
    906 
    907 unsigned long
    908 rt_timer_count(struct rttimer_queue *rtq)
    909 {
    910 	return rtq->rtq_count;
    911 }
    912 
    913 void
    914 rt_timer_remove_all(struct rtentry *rt, int destroy)
    915 {
    916 	struct rttimer *r;
    917 
    918 	while ((r = LIST_FIRST(&rt->rt_timer)) != NULL) {
    919 		LIST_REMOVE(r, rtt_link);
    920 		TAILQ_REMOVE(&r->rtt_queue->rtq_head, r, rtt_next);
    921 		if (destroy)
    922 			RTTIMER_CALLOUT(r);
    923 		if (r->rtt_queue->rtq_count > 0)
    924 			r->rtt_queue->rtq_count--;
    925 		else
    926 			printf("rt_timer_remove_all: rtq_count reached 0\n");
    927 		/* we are already at splsoftnet */
    928 		pool_put(&rttimer_pool, r);
    929 	}
    930 }
    931 
    932 int
    933 rt_timer_add(struct rtentry *rt,
    934 	void (*func)(struct rtentry *, struct rttimer *),
    935 	struct rttimer_queue *queue)
    936 {
    937 	struct rttimer *r;
    938 	int s;
    939 
    940 	/*
    941 	 * If there's already a timer with this action, destroy it before
    942 	 * we add a new one.
    943 	 */
    944 	for (r = LIST_FIRST(&rt->rt_timer); r != NULL;
    945 	     r = LIST_NEXT(r, rtt_link)) {
    946 		if (r->rtt_func == func) {
    947 			LIST_REMOVE(r, rtt_link);
    948 			TAILQ_REMOVE(&r->rtt_queue->rtq_head, r, rtt_next);
    949 			if (r->rtt_queue->rtq_count > 0)
    950 				r->rtt_queue->rtq_count--;
    951 			else
    952 				printf("rt_timer_add: rtq_count reached 0\n");
    953 			s = splsoftnet();
    954 			pool_put(&rttimer_pool, r);
    955 			splx(s);
    956 			break;  /* only one per list, so we can quit... */
    957 		}
    958 	}
    959 
    960 	s = splsoftnet();
    961 	r = pool_get(&rttimer_pool, PR_NOWAIT);
    962 	splx(s);
    963 	if (r == NULL)
    964 		return (ENOBUFS);
    965 	Bzero(r, sizeof(*r));
    966 
    967 	r->rtt_rt = rt;
    968 	r->rtt_time = time_uptime;
    969 	r->rtt_func = func;
    970 	r->rtt_queue = queue;
    971 	LIST_INSERT_HEAD(&rt->rt_timer, r, rtt_link);
    972 	TAILQ_INSERT_TAIL(&queue->rtq_head, r, rtt_next);
    973 	r->rtt_queue->rtq_count++;
    974 
    975 	return (0);
    976 }
    977 
    978 /* ARGSUSED */
    979 void
    980 rt_timer_timer(void *arg)
    981 {
    982 	struct rttimer_queue *rtq;
    983 	struct rttimer *r;
    984 	int s;
    985 
    986 	s = splsoftnet();
    987 	for (rtq = LIST_FIRST(&rttimer_queue_head); rtq != NULL;
    988 	     rtq = LIST_NEXT(rtq, rtq_link)) {
    989 		while ((r = TAILQ_FIRST(&rtq->rtq_head)) != NULL &&
    990 		    (r->rtt_time + rtq->rtq_timeout) < time_uptime) {
    991 			LIST_REMOVE(r, rtt_link);
    992 			TAILQ_REMOVE(&rtq->rtq_head, r, rtt_next);
    993 			RTTIMER_CALLOUT(r);
    994 			pool_put(&rttimer_pool, r);
    995 			if (rtq->rtq_count > 0)
    996 				rtq->rtq_count--;
    997 			else
    998 				printf("rt_timer_timer: rtq_count reached 0\n");
    999 		}
   1000 	}
   1001 	splx(s);
   1002 
   1003 	callout_reset(&rt_timer_ch, hz, rt_timer_timer, NULL);
   1004 }
   1005