2 * Copyright (c) 1980, 1986, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
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6 * modification, are permitted provided that the following conditions
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9 * notice, this list of conditions and the following disclaimer.
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13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
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17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * @(#)route.c 8.2 (Berkeley) 11/15/93
34 * $Id: route.c,v 1.49 1998/02/09 06:09:59 eivind Exp $
38 #include "opt_mrouting.h"
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/malloc.h>
44 #include <sys/socket.h>
45 #include <sys/domain.h>
48 #include <net/route.h>
50 #include <netinet/in.h>
51 #include <netinet/ip_mroute.h>
53 #define SA(p) ((struct sockaddr *)(p))
55 struct route_cb route_cb;
56 static struct rtstat rtstat;
57 struct radix_node_head *rt_tables[AF_MAX+1];
59 static int rttrash; /* routes not in table but not freed */
61 static void rt_maskedcopy __P((struct sockaddr *,
62 struct sockaddr *, struct sockaddr *));
63 static void rtable_init __P((void **));
70 for (dom = domains; dom; dom = dom->dom_next)
71 if (dom->dom_rtattach)
72 dom->dom_rtattach(&table[dom->dom_family],
79 rn_init(); /* initialize all zeroes, all ones, mask table */
80 rtable_init((void **)rt_tables);
84 * Packet routing routines.
88 register struct route *ro;
90 if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
92 ro->ro_rt = rtalloc1(&ro->ro_dst, 1, 0UL);
96 rtalloc_ign(ro, ignore)
97 register struct route *ro;
100 if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
102 ro->ro_rt = rtalloc1(&ro->ro_dst, 1, ignore);
106 * Look up the route that matches the address given
107 * Or, at least try.. Create a cloned route if needed.
110 rtalloc1(dst, report, ignflags)
111 register struct sockaddr *dst;
115 register struct radix_node_head *rnh = rt_tables[dst->sa_family];
116 register struct rtentry *rt;
117 register struct radix_node *rn;
118 struct rtentry *newrt = 0;
119 struct rt_addrinfo info;
121 int s = splnet(), err = 0, msgtype = RTM_MISS;
124 * Look up the address in the table for that Address Family
126 if (rnh && (rn = rnh->rnh_matchaddr((caddr_t)dst, rnh)) &&
127 ((rn->rn_flags & RNF_ROOT) == 0)) {
129 * If we find it and it's not the root node, then
130 * get a refernce on the rtentry associated.
132 newrt = rt = (struct rtentry *)rn;
133 nflags = rt->rt_flags & ~ignflags;
134 if (report && (nflags & (RTF_CLONING | RTF_PRCLONING))) {
136 * We are apparently adding (report = 0 in delete).
137 * If it requires that it be cloned, do so.
138 * (This implies it wasn't a HOST route.)
140 err = rtrequest(RTM_RESOLVE, dst, SA(0),
144 * If the cloning didn't succeed, maybe
145 * what we have will do. Return that.
151 if ((rt = newrt) && (rt->rt_flags & RTF_XRESOLVE)) {
153 * If the new route specifies it be
154 * externally resolved, then go do that.
156 msgtype = RTM_RESOLVE;
163 * Either we hit the root or couldn't find any match,
164 * Which basically means
165 * "caint get there frm here"
167 rtstat.rts_unreach++;
170 * If required, report the failure to the supervising
172 * For a delete, this is not an error. (report == 0)
174 bzero((caddr_t)&info, sizeof(info));
175 info.rti_info[RTAX_DST] = dst;
176 rt_missmsg(msgtype, &info, 0, err);
184 * Remove a reference count from an rtentry.
185 * If the count gets low enough, take it out of the routing table
189 register struct rtentry *rt;
192 * find the tree for that address family
194 register struct radix_node_head *rnh =
195 rt_tables[rt_key(rt)->sa_family];
196 register struct ifaddr *ifa;
198 if (rt == 0 || rnh == 0)
202 * decrement the reference count by one and if it reaches 0,
203 * and there is a close function defined, call the close function
206 if(rnh->rnh_close && rt->rt_refcnt == 0) {
207 rnh->rnh_close((struct radix_node *)rt, rnh);
211 * If we are no longer "up" (and ref == 0)
212 * then we can free the resources associated
215 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_UP) == 0) {
216 if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT))
219 * the rtentry must have been removed from the routing table
220 * so it is represented in rttrash.. remove that now.
225 if (rt->rt_refcnt < 0) {
226 printf("rtfree: %p not freed (neg refs)\n", rt);
232 * release references on items we hold them on..
233 * e.g other routes and ifaddrs.
235 if((ifa = rt->rt_ifa))
238 RTFREE(rt->rt_parent);
242 * The key is separatly alloc'd so free it (see rt_setgate()).
243 * This also frees the gateway, as they are always malloc'd
249 * and the rtentry itself of course
257 register struct ifaddr *ifa;
261 if (ifa->ifa_refcnt == 0)
268 * Force a routing table entry to the specified
269 * destination to go through the given gateway.
270 * Normally called as a result of a routing redirect
271 * message from the network layer.
273 * N.B.: must be called at splnet
277 rtredirect(dst, gateway, netmask, flags, src, rtp)
278 struct sockaddr *dst, *gateway, *netmask, *src;
280 struct rtentry **rtp;
282 register struct rtentry *rt;
285 struct rt_addrinfo info;
288 /* verify the gateway is directly reachable */
289 if ((ifa = ifa_ifwithnet(gateway)) == 0) {
293 rt = rtalloc1(dst, 0, 0UL);
295 * If the redirect isn't from our current router for this dst,
296 * it's either old or wrong. If it redirects us to ourselves,
297 * we have a routing loop, perhaps as a result of an interface
298 * going down recently.
300 #define equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0)
301 if (!(flags & RTF_DONE) && rt &&
302 (!equal(src, rt->rt_gateway) || rt->rt_ifa != ifa))
304 else if (ifa_ifwithaddr(gateway))
305 error = EHOSTUNREACH;
309 * Create a new entry if we just got back a wildcard entry
310 * or the the lookup failed. This is necessary for hosts
311 * which use routing redirects generated by smart gateways
312 * to dynamically build the routing tables.
314 if ((rt == 0) || (rt_mask(rt) && rt_mask(rt)->sa_len < 2))
317 * Don't listen to the redirect if it's
318 * for a route to an interface.
320 if (rt->rt_flags & RTF_GATEWAY) {
321 if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) {
323 * Changing from route to net => route to host.
324 * Create new route, rather than smashing route to net.
327 flags |= RTF_GATEWAY | RTF_DYNAMIC;
328 error = rtrequest((int)RTM_ADD, dst, gateway,
330 (struct rtentry **)0);
331 stat = &rtstat.rts_dynamic;
334 * Smash the current notion of the gateway to
335 * this destination. Should check about netmask!!!
337 rt->rt_flags |= RTF_MODIFIED;
338 flags |= RTF_MODIFIED;
339 stat = &rtstat.rts_newgateway;
341 * add the key and gateway (in one malloc'd chunk).
343 rt_setgate(rt, rt_key(rt), gateway);
346 error = EHOSTUNREACH;
356 rtstat.rts_badredirect++;
357 else if (stat != NULL)
359 bzero((caddr_t)&info, sizeof(info));
360 info.rti_info[RTAX_DST] = dst;
361 info.rti_info[RTAX_GATEWAY] = gateway;
362 info.rti_info[RTAX_NETMASK] = netmask;
363 info.rti_info[RTAX_AUTHOR] = src;
364 rt_missmsg(RTM_REDIRECT, &info, flags, error);
368 * Routing table ioctl interface.
371 rtioctl(req, data, p)
377 /* Multicast goop, grrr... */
379 return mrt_ioctl(req, data);
381 return mrt_ioctl(req, data, p);
389 ifa_ifwithroute(flags, dst, gateway)
391 struct sockaddr *dst, *gateway;
393 register struct ifaddr *ifa;
394 if ((flags & RTF_GATEWAY) == 0) {
396 * If we are adding a route to an interface,
397 * and the interface is a pt to pt link
398 * we should search for the destination
399 * as our clue to the interface. Otherwise
400 * we can use the local address.
403 if (flags & RTF_HOST) {
404 ifa = ifa_ifwithdstaddr(dst);
407 ifa = ifa_ifwithaddr(gateway);
410 * If we are adding a route to a remote net
411 * or host, the gateway may still be on the
412 * other end of a pt to pt link.
414 ifa = ifa_ifwithdstaddr(gateway);
417 ifa = ifa_ifwithnet(gateway);
419 struct rtentry *rt = rtalloc1(dst, 0, 0UL);
423 if ((ifa = rt->rt_ifa) == 0)
426 if (ifa->ifa_addr->sa_family != dst->sa_family) {
427 struct ifaddr *oifa = ifa;
428 ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
435 #define ROUNDUP(a) (a>0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
437 static int rt_fixdelete __P((struct radix_node *, void *));
438 static int rt_fixchange __P((struct radix_node *, void *));
442 struct radix_node_head *rnh;
446 * Do appropriate manipulations of a routing tree given
447 * all the bits of info needed
450 rtrequest(req, dst, gateway, netmask, flags, ret_nrt)
452 struct sockaddr *dst, *gateway, *netmask;
453 struct rtentry **ret_nrt;
455 int s = splnet(); int error = 0;
456 register struct rtentry *rt;
457 register struct radix_node *rn;
458 register struct radix_node_head *rnh;
460 struct sockaddr *ndst;
461 #define senderr(x) { error = x ; goto bad; }
464 * Find the correct routing tree to use for this Address Family
466 if ((rnh = rt_tables[dst->sa_family]) == 0)
469 * If we are adding a host route then we don't want to put
470 * a netmask in the tree
472 if (flags & RTF_HOST)
477 * Remove the item from the tree and return it.
478 * Complain if it is not there and do no more processing.
480 if ((rn = rnh->rnh_deladdr(dst, netmask, rnh)) == 0)
482 if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT))
483 panic ("rtrequest delete");
484 rt = (struct rtentry *)rn;
487 * Now search what's left of the subtree for any cloned
488 * routes which might have been formed from this node.
490 if ((rt->rt_flags & RTF_PRCLONING) && netmask) {
491 rnh->rnh_walktree_from(rnh, dst, netmask,
496 * Remove any external references we may have.
497 * This might result in another rtentry being freed if
498 * we held its last reference.
500 if (rt->rt_gwroute) {
503 (rt = (struct rtentry *)rn)->rt_gwroute = 0;
507 * NB: RTF_UP must be set during the search above,
508 * because we might delete the last ref, causing
509 * rt to get freed prematurely.
510 * eh? then why not just add a reference?
511 * I'm not sure how RTF_UP helps matters. (JRE)
513 rt->rt_flags &= ~RTF_UP;
516 * give the protocol a chance to keep things in sync.
518 if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
519 ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
522 * one more rtentry floating around that is not
523 * linked to the routing table.
528 * If the caller wants it, then it can have it,
529 * but it's up to it to free the rtentry as we won't be
534 else if (rt->rt_refcnt <= 0) {
535 rt->rt_refcnt++; /* make a 1->0 transition */
541 if (ret_nrt == 0 || (rt = *ret_nrt) == 0)
544 flags = rt->rt_flags &
545 ~(RTF_CLONING | RTF_PRCLONING | RTF_STATIC);
546 flags |= RTF_WASCLONED;
547 gateway = rt->rt_gateway;
548 if ((netmask = rt->rt_genmask) == 0)
553 if ((flags & RTF_GATEWAY) && !gateway)
554 panic("rtrequest: GATEWAY but no gateway");
556 if ((ifa = ifa_ifwithroute(flags, dst, gateway)) == 0)
557 senderr(ENETUNREACH);
560 R_Malloc(rt, struct rtentry *, sizeof(*rt));
563 Bzero(rt, sizeof(*rt));
564 rt->rt_flags = RTF_UP | flags;
566 * Add the gateway. Possibly re-malloc-ing the storage for it
567 * also add the rt_gwroute if possible.
569 if (error = rt_setgate(rt, dst, gateway)) {
575 * point to the (possibly newly malloc'd) dest address.
580 * make sure it contains the value we want (masked if needed).
583 rt_maskedcopy(dst, ndst, netmask);
585 Bcopy(dst, ndst, dst->sa_len);
588 * Note that we now have a reference to the ifa.
589 * This moved from below so that rnh->rnh_addaddr() can
590 * examine the ifa and ifa->ifa_ifp if it so desires.
594 rt->rt_ifp = ifa->ifa_ifp;
596 rn = rnh->rnh_addaddr((caddr_t)ndst, (caddr_t)netmask,
601 * Uh-oh, we already have one of these in the tree.
602 * We do a special hack: if the route that's already
603 * there was generated by the protocol-cloning
604 * mechanism, then we just blow it away and retry
605 * the insertion of the new one.
607 rt2 = rtalloc1(dst, 0, RTF_PRCLONING);
608 if (rt2 && rt2->rt_parent) {
609 rtrequest(RTM_DELETE,
610 (struct sockaddr *)rt_key(rt2),
612 rt_mask(rt2), rt2->rt_flags, 0);
614 rn = rnh->rnh_addaddr((caddr_t)ndst,
618 /* undo the extra ref we got */
624 * If it still failed to go into the tree,
625 * then un-make it (this should be a function)
629 rtfree(rt->rt_gwroute);
641 * If we got here from RESOLVE, then we are cloning
642 * so clone the rest, and note that we
643 * are a clone (and increment the parent's references)
645 if (req == RTM_RESOLVE) {
646 rt->rt_rmx = (*ret_nrt)->rt_rmx; /* copy metrics */
647 if ((*ret_nrt)->rt_flags & RTF_PRCLONING) {
648 rt->rt_parent = (*ret_nrt);
649 (*ret_nrt)->rt_refcnt++;
654 * if this protocol has something to add to this then
655 * allow it to do that as well.
657 if (ifa->ifa_rtrequest)
658 ifa->ifa_rtrequest(req, rt, SA(ret_nrt ? *ret_nrt : 0));
661 * We repeat the same procedure from rt_setgate() here because
662 * it doesn't fire when we call it there because the node
663 * hasn't been added to the tree yet.
665 if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != 0) {
669 rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
674 * actually return a resultant rtentry and
675 * give the caller a single reference.
689 * Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family''
690 * (i.e., the routes related to it by the operation of cloning). This
691 * routine is iterated over all potential former-child-routes by way of
692 * rnh->rnh_walktree_from() above, and those that actually are children of
693 * the late parent (passed in as VP here) are themselves deleted.
697 struct radix_node *rn;
700 struct rtentry *rt = (struct rtentry *)rn;
701 struct rtentry *rt0 = vp;
703 if (rt->rt_parent == rt0 && !(rt->rt_flags & RTF_PINNED)) {
704 return rtrequest(RTM_DELETE, rt_key(rt),
705 (struct sockaddr *)0, rt_mask(rt),
706 rt->rt_flags, (struct rtentry **)0);
712 * This routine is called from rt_setgate() to do the analogous thing for
713 * adds and changes. There is the added complication in this case of a
714 * middle insert; i.e., insertion of a new network route between an older
715 * network route and (cloned) host routes. For this reason, a simple check
716 * of rt->rt_parent is insufficient; each candidate route must be tested
717 * against the (mask, value) of the new route (passed as before in vp)
718 * to see if the new route matches it. Unfortunately, this has the obnoxious
719 * property of also triggering for insertion /above/ a pre-existing network
720 * route and clones. Sigh. This may be fixed some day.
722 * XXX - it may be possible to do fixdelete() for changes and reserve this
723 * routine just for adds. I'm not sure why I thought it was necessary to do
727 static int rtfcdebug = 0;
732 struct radix_node *rn;
735 struct rtentry *rt = (struct rtentry *)rn;
736 struct rtfc_arg *ap = vp;
737 struct rtentry *rt0 = ap->rt0;
738 struct radix_node_head *rnh = ap->rnh;
739 u_char *xk1, *xm1, *xk2;
744 printf("rt_fixchange: rt %p, rt0 %p\n", rt, rt0);
747 if (!rt->rt_parent || (rt->rt_flags & RTF_PINNED)) {
749 if(rtfcdebug) printf("no parent or pinned\n");
754 if (rt->rt_parent == rt0) {
756 if(rtfcdebug) printf("parent match\n");
758 return rtrequest(RTM_DELETE, rt_key(rt),
759 (struct sockaddr *)0, rt_mask(rt),
760 rt->rt_flags, (struct rtentry **)0);
764 * There probably is a function somewhere which does this...
765 * if not, there should be.
767 len = imin(((struct sockaddr *)rt_key(rt0))->sa_len,
768 ((struct sockaddr *)rt_key(rt))->sa_len);
770 xk1 = (u_char *)rt_key(rt0);
771 xm1 = (u_char *)rt_mask(rt0);
772 xk2 = (u_char *)rt_key(rt);
774 for (i = rnh->rnh_treetop->rn_off; i < len; i++) {
775 if ((xk2[i] & xm1[i]) != xk1[i]) {
777 if(rtfcdebug) printf("no match\n");
784 * OK, this node is a clone, and matches the node currently being
785 * changed/added under the node's mask. So, get rid of it.
788 if(rtfcdebug) printf("deleting\n");
790 return rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0,
791 rt_mask(rt), rt->rt_flags, (struct rtentry **)0);
795 rt_setgate(rt0, dst, gate)
797 struct sockaddr *dst, *gate;
800 int dlen = ROUNDUP(dst->sa_len), glen = ROUNDUP(gate->sa_len);
801 register struct rtentry *rt = rt0;
802 struct radix_node_head *rnh = rt_tables[dst->sa_family];
805 * A host route with the destination equal to the gateway
806 * will interfere with keeping LLINFO in the routing
807 * table, so disallow it.
809 if (((rt0->rt_flags & (RTF_HOST|RTF_GATEWAY|RTF_LLINFO)) ==
810 (RTF_HOST|RTF_GATEWAY)) &&
811 (dst->sa_len == gate->sa_len) &&
812 (bcmp(dst, gate, dst->sa_len) == 0)) {
814 * The route might already exist if this is an RTM_CHANGE
815 * or a routing redirect, so try to delete it.
818 rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt0),
819 rt0->rt_gateway, rt_mask(rt0), rt0->rt_flags, 0);
820 return EADDRNOTAVAIL;
824 * Both dst and gateway are stored in the same malloc'd chunk
825 * (If I ever get my hands on....)
826 * if we need to malloc a new chunk, then keep the old one around
827 * till we don't need it any more.
829 if (rt->rt_gateway == 0 || glen > ROUNDUP(rt->rt_gateway->sa_len)) {
830 old = (caddr_t)rt_key(rt);
831 R_Malloc(new, caddr_t, dlen + glen);
834 rt->rt_nodes->rn_key = new;
837 * otherwise just overwrite the old one
839 new = rt->rt_nodes->rn_key;
844 * copy the new gateway value into the memory chunk
846 Bcopy(gate, (rt->rt_gateway = (struct sockaddr *)(new + dlen)), glen);
849 * if we are replacing the chunk (or it's new) we need to
850 * replace the dst as well
853 Bcopy(dst, new, dlen);
858 * If there is already a gwroute, it's now almost definitly wrong
861 if (rt->rt_gwroute) {
862 rt = rt->rt_gwroute; RTFREE(rt);
863 rt = rt0; rt->rt_gwroute = 0;
866 * Cloning loop avoidance:
867 * In the presence of protocol-cloning and bad configuration,
868 * it is possible to get stuck in bottomless mutual recursion
869 * (rtrequest rt_setgate rtalloc1). We avoid this by not allowing
870 * protocol-cloning to operate for gateways (which is probably the
871 * correct choice anyway), and avoid the resulting reference loops
872 * by disallowing any route to run through itself as a gateway.
873 * This is obviously mandatory when we get rt->rt_output().
875 if (rt->rt_flags & RTF_GATEWAY) {
876 rt->rt_gwroute = rtalloc1(gate, 1, RTF_PRCLONING);
877 if (rt->rt_gwroute == rt) {
878 RTFREE(rt->rt_gwroute);
880 return EDQUOT; /* failure */
885 * This isn't going to do anything useful for host routes, so
886 * don't bother. Also make sure we have a reasonable mask
887 * (we don't yet have one during adds).
889 if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != 0) {
893 rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
901 rt_maskedcopy(src, dst, netmask)
902 struct sockaddr *src, *dst, *netmask;
904 register u_char *cp1 = (u_char *)src;
905 register u_char *cp2 = (u_char *)dst;
906 register u_char *cp3 = (u_char *)netmask;
907 u_char *cplim = cp2 + *cp3;
908 u_char *cplim2 = cp2 + *cp1;
910 *cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
915 *cp2++ = *cp1++ & *cp3++;
917 bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2));
921 * Set up a routing table entry, normally
925 rtinit(ifa, cmd, flags)
926 register struct ifaddr *ifa;
929 register struct rtentry *rt;
930 register struct sockaddr *dst;
931 register struct sockaddr *deldst;
933 struct rtentry *nrt = 0;
936 dst = flags & RTF_HOST ? ifa->ifa_dstaddr : ifa->ifa_addr;
938 * If it's a delete, check that if it exists, it's on the correct
939 * interface or we might scrub a route to another ifa which would
940 * be confusing at best and possibly worse.
942 if (cmd == RTM_DELETE) {
944 * It's a delete, so it should already exist..
945 * If it's a net, mask off the host bits
946 * (Assuming we have a mask)
948 if ((flags & RTF_HOST) == 0 && ifa->ifa_netmask) {
949 m = m_get(M_WAIT, MT_SONAME);
950 deldst = mtod(m, struct sockaddr *);
951 rt_maskedcopy(dst, deldst, ifa->ifa_netmask);
955 * Get an rtentry that is in the routing tree and
956 * contains the correct info. (if this fails, can't get there).
957 * We set "report" to FALSE so that if it doesn't exist,
958 * it doesn't report an error or clone a route, etc. etc.
960 rt = rtalloc1(dst, 0, 0UL);
963 * Ok so we found the rtentry. it has an extra reference
964 * for us at this stage. we won't need that so
968 if (rt->rt_ifa != ifa) {
970 * If the interface in the rtentry doesn't match
971 * the interface we are using, then we don't
972 * want to delete it, so return an error.
973 * This seems to be the only point of
974 * this whole RTM_DELETE clause.
978 return (flags & RTF_HOST ? EHOSTUNREACH
986 * One would think that as we are deleting, and we know
987 * it doesn't exist, we could just return at this point
988 * with an "ELSE" clause, but apparently not..
990 return (flags & RTF_HOST ? EHOSTUNREACH
996 * Do the actual request
998 error = rtrequest(cmd, dst, ifa->ifa_addr, ifa->ifa_netmask,
999 flags | ifa->ifa_flags, &nrt);
1003 * If we are deleting, and we found an entry, then
1004 * it's been removed from the tree.. now throw it away.
1006 if (cmd == RTM_DELETE && error == 0 && (rt = nrt)) {
1008 * notify any listenning routing agents of the change
1010 rt_newaddrmsg(cmd, ifa, error, nrt);
1011 if (rt->rt_refcnt <= 0) {
1012 rt->rt_refcnt++; /* need a 1->0 transition to free */
1018 * We are adding, and we have a returned routing entry.
1019 * We need to sanity check the result.
1021 if (cmd == RTM_ADD && error == 0 && (rt = nrt)) {
1023 * We just wanted to add it.. we don't actually need a reference
1027 * If it came back with an unexpected interface, then it must
1028 * have already existed or something. (XXX)
1030 if (rt->rt_ifa != ifa) {
1031 printf("rtinit: wrong ifa (%p) was (%p)\n", ifa,
1034 * Ask that the protocol in question
1035 * remove anything it has associated with
1036 * this route and ifaddr.
1038 if (rt->rt_ifa->ifa_rtrequest)
1039 rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
1041 * Remove the referenve to the it's ifaddr.
1043 IFAFREE(rt->rt_ifa);
1045 * And substitute in references to the ifaddr
1049 rt->rt_ifp = ifa->ifa_ifp;
1052 * Now ask the protocol to check if it needs
1053 * any special processing in its new form.
1055 if (ifa->ifa_rtrequest)
1056 ifa->ifa_rtrequest(RTM_ADD, rt, SA(0));
1059 * notify any listenning routing agents of the change
1061 rt_newaddrmsg(cmd, ifa, error, nrt);