2 * Copyright (c) 1983, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 #elif defined(__FreeBSD__)
39 __RCSID("$Revision: 2.27 $");
40 #ident "$Revision: 2.27 $"
43 static struct rt_spare *rts_better(struct rt_entry *);
44 static struct rt_spare rts_empty = {0,0,0,HOPCNT_INFINITY,0,0,0};
45 static void set_need_flash(void);
47 static void masktrim(struct sockaddr_in *ap);
49 static void masktrim(struct sockaddr_in_new *ap);
53 struct radix_node_head *rhead; /* root of the radix tree */
55 int need_flash = 1; /* flash update needed
56 * start =1 to suppress the 1st
59 struct timeval age_timer; /* next check of old routes */
60 struct timeval need_kern = { /* need to update kernel table */
61 EPOCH+MIN_WAITTIME-1, 0
68 /* zap any old routes through this gateway */
72 /* It is desirable to "aggregate" routes, to combine differing routes of
73 * the same metric and next hop into a common route with a smaller netmask
74 * or to suppress redundant routes, routes that add no information to
75 * routes with smaller netmasks.
77 * A route is redundant if and only if any and all routes with smaller
78 * but matching netmasks and nets are the same. Since routes are
79 * kept sorted in the radix tree, redundant routes always come second.
81 * There are two kinds of aggregations. First, two routes of the same bit
82 * mask and differing only in the least significant bit of the network
83 * number can be combined into a single route with a coarser mask.
85 * Second, a route can be suppressed in favor of another route with a more
86 * coarse mask provided no incompatible routes with intermediate masks
87 * are present. The second kind of aggregation involves suppressing routes.
88 * A route must not be suppressed if an incompatible route exists with
89 * an intermediate mask, since the suppressed route would be covered
90 * by the intermediate.
92 * This code relies on the radix tree walk encountering routes
93 * sorted first by address, with the smallest address first.
96 struct ag_info ag_slots[NUM_AG_SLOTS], *ag_avail, *ag_corsest, *ag_finest;
98 /* #define DEBUG_AG */
100 #define CHECK_AG() {int acnt = 0; struct ag_info *cag; \
101 for (cag = ag_avail; cag != 0; cag = cag->ag_fine) \
103 for (cag = ag_corsest; cag != 0; cag = cag->ag_fine) \
105 if (acnt != NUM_AG_SLOTS) { \
106 (void)fflush(stderr); \
115 /* Output the contents of an aggregation table slot.
116 * This function must always be immediately followed with the deletion
117 * of the target slot.
120 ag_out(struct ag_info *ag,
121 void (*out)(struct ag_info *))
123 struct ag_info *ag_cors;
127 /* Forget it if this route should not be output for split-horizon. */
128 if (ag->ag_state & AGS_SPLIT_HZ)
131 /* If we output both the even and odd twins, then the immediate parent,
132 * if it is present, is redundant, unless the parent manages to
133 * aggregate into something coarser.
134 * On successive calls, this code detects the even and odd twins,
135 * and marks the parent.
137 * Note that the order in which the radix tree code emits routes
138 * ensures that the twins are seen before the parent is emitted.
140 ag_cors = ag->ag_cors;
142 && ag_cors->ag_mask == ag->ag_mask<<1
143 && ag_cors->ag_dst_h == (ag->ag_dst_h & ag_cors->ag_mask)) {
144 ag_cors->ag_state |= ((ag_cors->ag_dst_h == ag->ag_dst_h)
149 /* Skip it if this route is itself redundant.
151 * It is ok to change the contents of the slot here, since it is
152 * always deleted next.
154 if (ag->ag_state & AGS_REDUN0) {
155 if (ag->ag_state & AGS_REDUN1)
156 return; /* quit if fully redundant */
157 /* make it finer if it is half-redundant */
158 bit = (-ag->ag_mask) >> 1;
162 } else if (ag->ag_state & AGS_REDUN1) {
163 /* make it finer if it is half-redundant */
164 bit = (-ag->ag_mask) >> 1;
172 ag_del(struct ag_info *ag)
176 if (ag->ag_cors == 0)
177 ag_corsest = ag->ag_fine;
179 ag->ag_cors->ag_fine = ag->ag_fine;
181 if (ag->ag_fine == 0)
182 ag_finest = ag->ag_cors;
184 ag->ag_fine->ag_cors = ag->ag_cors;
186 ag->ag_fine = ag_avail;
193 /* Flush routes waiting for aggregation.
194 * This must not suppress a route unless it is known that among all
195 * routes with coarser masks that match it, the one with the longest
196 * mask is appropriate. This is ensured by scanning the routes
197 * in lexical order, and with the most restrictive mask first
198 * among routes to the same destination.
201 ag_flush(naddr lim_dst_h, /* flush routes to here */
202 naddr lim_mask, /* matching this mask */
203 void (*out)(struct ag_info *))
205 struct ag_info *ag, *ag_cors;
210 ag != 0 && ag->ag_mask >= lim_mask;
212 ag_cors = ag->ag_cors;
214 /* work on only the specified routes */
215 dst_h = ag->ag_dst_h;
216 if ((dst_h & lim_mask) != lim_dst_h)
219 if (!(ag->ag_state & AGS_SUPPRESS))
222 else for ( ; ; ag_cors = ag_cors->ag_cors) {
223 /* Look for a route that can suppress the
226 /* failed, so output it and look for
227 * another route to work on
233 if ((dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h) {
234 /* We found a route with a coarser mask that
235 * aggregates the current target.
237 * If it has a different next hop, it
238 * cannot replace the target, so output
241 if (ag->ag_gate != ag_cors->ag_gate
242 && !(ag->ag_state & AGS_FINE_GATE)
243 && !(ag_cors->ag_state & AGS_CORS_GATE)) {
248 /* If the coarse route has a good enough
249 * metric, it suppresses the target.
250 * If the suppressed target was redundant,
251 * then mark the suppressor redundant.
253 if (ag_cors->ag_pref <= ag->ag_pref) {
254 if (AG_IS_REDUN(ag->ag_state)
255 && ag_cors->ag_mask==ag->ag_mask<<1) {
256 if (ag_cors->ag_dst_h == dst_h)
257 ag_cors->ag_state |= AGS_REDUN0;
259 ag_cors->ag_state |= AGS_REDUN1;
261 if (ag->ag_tag != ag_cors->ag_tag)
263 if (ag->ag_nhop != ag_cors->ag_nhop)
264 ag_cors->ag_nhop = 0;
270 /* That route has either been output or suppressed */
271 ag_cors = ag->ag_cors;
279 /* Try to aggregate a route with previous routes.
291 void (*out)(struct ag_info *)) /* output using this */
293 struct ag_info *ag, *nag, *ag_cors;
299 /* Punt non-contiguous subnet masks.
301 * (X & -X) contains a single bit if and only if X is a power of 2.
302 * (X + (X & -X)) == 0 if and only if X is a power of 2.
304 if ((mask & -mask) + mask != 0) {
305 struct ag_info nc_ag;
307 nc_ag.ag_dst_h = dst;
308 nc_ag.ag_mask = mask;
309 nc_ag.ag_gate = gate;
310 nc_ag.ag_nhop = nhop;
311 nc_ag.ag_metric = metric;
312 nc_ag.ag_pref = pref;
314 nc_ag.ag_state = state;
315 nc_ag.ag_seqno = new_seqno;
320 /* Search for the right slot in the aggregation table.
325 if (ag->ag_mask >= mask)
328 /* Suppress old routes (i.e. combine with compatible routes
329 * with coarser masks) as we look for the right slot in the
330 * aggregation table for the new route.
331 * A route to an address less than the current destination
332 * will not be affected by the current route or any route
333 * seen hereafter. That means it is safe to suppress it.
334 * This check keeps poor routes (e.g. with large hop counts)
335 * from preventing suppression of finer routes.
338 && ag->ag_dst_h < dst
339 && (ag->ag_state & AGS_SUPPRESS)
340 && ag_cors->ag_pref <= ag->ag_pref
341 && (ag->ag_dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h
342 && (ag_cors->ag_gate == ag->ag_gate
343 || (ag->ag_state & AGS_FINE_GATE)
344 || (ag_cors->ag_state & AGS_CORS_GATE))) {
345 /* If the suppressed target was redundant,
346 * then mark the suppressor redundant.
348 if (AG_IS_REDUN(ag->ag_state)
349 && ag_cors->ag_mask == ag->ag_mask<<1) {
350 if (ag_cors->ag_dst_h == dst)
351 ag_cors->ag_state |= AGS_REDUN0;
353 ag_cors->ag_state |= AGS_REDUN1;
355 if (ag->ag_tag != ag_cors->ag_tag)
357 if (ag->ag_nhop != ag_cors->ag_nhop)
358 ag_cors->ag_nhop = 0;
364 ag = ag_cors->ag_fine;
367 /* If we find the even/odd twin of the new route, and if the
368 * masks and so forth are equal, we can aggregate them.
369 * We can probably promote one of the pair.
371 * Since the routes are encountered in lexical order,
372 * the new route must be odd. However, the second or later
373 * times around this loop, it could be the even twin promoted
374 * from the even/odd pair of twins of the finer route.
377 && ag->ag_mask == mask
378 && ((ag->ag_dst_h ^ dst) & (mask<<1)) == 0) {
380 /* Here we know the target route and the route in the current
381 * slot have the same netmasks and differ by at most the
382 * last bit. They are either for the same destination, or
383 * for an even/odd pair of destinations.
385 if (ag->ag_dst_h == dst) {
386 /* We have two routes to the same destination.
387 * Routes are encountered in lexical order, so a
388 * route is never promoted until the parent route is
389 * already present. So we know that the new route is
390 * a promoted (or aggregated) pair and the route
391 * already in the slot is the explicit route.
393 * Prefer the best route if their metrics differ,
394 * or the aggregated one if not, following a sort
395 * of longest-match rule.
397 if (pref <= ag->ag_pref) {
401 ag->ag_metric = metric;
403 if (ag->ag_seqno < new_seqno)
404 ag->ag_seqno = new_seqno;
406 ag->ag_state = state;
410 /* Some bits are set if they are set on either route,
411 * except when the route is for an interface.
413 if (!(ag->ag_state & AGS_IF))
414 ag->ag_state |= (state & (AGS_AGGREGATE_EITHER
420 /* If one of the routes can be promoted and the other can
421 * be suppressed, it may be possible to combine them or
422 * worthwhile to promote one.
424 * Any route that can be promoted is always
425 * marked to be eligible to be suppressed.
427 if (!((state & AGS_AGGREGATE)
428 && (ag->ag_state & AGS_SUPPRESS))
429 && !((ag->ag_state & AGS_AGGREGATE)
430 && (state & AGS_SUPPRESS)))
433 /* A pair of even/odd twin routes can be combined
434 * if either is redundant, or if they are via the
435 * same gateway and have the same metric.
437 if (AG_IS_REDUN(ag->ag_state)
438 || AG_IS_REDUN(state)
439 || (ag->ag_gate == gate
440 && ag->ag_pref == pref
441 && (state & ag->ag_state & AGS_AGGREGATE) != 0)) {
443 /* We have both the even and odd pairs.
444 * Since the routes are encountered in order,
445 * the route in the slot must be the even twin.
447 * Combine and promote (aggregate) the pair of routes.
449 if (new_seqno < ag->ag_seqno)
450 new_seqno = ag->ag_seqno;
451 if (!AG_IS_REDUN(state))
452 state &= ~AGS_REDUN1;
453 if (AG_IS_REDUN(ag->ag_state))
456 state &= ~AGS_REDUN0;
457 state |= (ag->ag_state & AGS_AGGREGATE_EITHER);
458 if (ag->ag_tag != tag)
460 if (ag->ag_nhop != nhop)
463 /* Get rid of the even twin that was already
468 } else if (ag->ag_pref >= pref
469 && (ag->ag_state & AGS_AGGREGATE)) {
470 /* If we cannot combine the pair, maybe the route
471 * with the worse metric can be promoted.
473 * Promote the old, even twin, by giving its slot
474 * in the table to the new, odd twin.
490 /* The promoted route is even-redundant only if the
491 * even twin was fully redundant. It is not
492 * odd-redundant because the odd-twin will still be
499 ag->ag_state = state;
503 ag->ag_metric = metric;
510 /* take the newest sequence number */
511 if (new_seqno <= ag->ag_seqno)
512 new_seqno = ag->ag_seqno;
514 ag->ag_seqno = new_seqno;
517 if (!(state & AGS_AGGREGATE))
518 break; /* cannot promote either twin */
520 /* Promote the new, odd twin by shaving its
522 * The promoted route is odd-redundant only if the
523 * odd twin was fully redundant. It is not
524 * even-redundant because the even twin is still in
527 if (!AG_IS_REDUN(state))
528 state &= ~AGS_REDUN1;
529 state &= ~AGS_REDUN0;
530 if (new_seqno < ag->ag_seqno)
531 new_seqno = ag->ag_seqno;
533 ag->ag_seqno = new_seqno;
544 ag_cors = ag->ag_cors;
547 /* When we can no longer promote and combine routes,
548 * flush the old route in the target slot. Also flush
549 * any finer routes that we know will never be aggregated by
552 * In case we moved toward coarser masks,
553 * get back where we belong
556 && ag->ag_mask < mask) {
561 /* Empty the target slot
563 if (ag != 0 && ag->ag_mask == mask) {
564 ag_flush(ag->ag_dst_h, ag->ag_mask, out);
565 ag = (ag_cors == 0) ? ag_corsest : ag_cors->ag_fine;
569 (void)fflush(stderr);
570 if (ag == 0 && ag_cors != ag_finest)
572 if (ag_cors == 0 && ag != ag_corsest)
574 if (ag != 0 && ag->ag_cors != ag_cors)
576 if (ag_cors != 0 && ag_cors->ag_fine != ag)
581 /* Save the new route on the end of the table.
584 ag_avail = nag->ag_fine;
590 nag->ag_metric = metric;
593 nag->ag_state = state;
594 nag->ag_seqno = new_seqno;
601 nag->ag_cors = ag_cors;
605 ag_cors->ag_fine = nag;
612 rtm_type_name(u_char type)
614 static const char *rtm_types[] = {
635 #define NEW_RTM_PAT "RTM type %#x"
636 static char name0[sizeof(NEW_RTM_PAT)+2];
639 if (type > sizeof(rtm_types)/sizeof(rtm_types[0])
641 snprintf(name0, sizeof(name0), NEW_RTM_PAT, type);
644 return rtm_types[type-1];
650 /* Trim a mask in a sockaddr
651 * Produce a length of 0 for an address of 0.
652 * Otherwise produce the index of the first zero byte.
656 masktrim(struct sockaddr_in *ap)
658 masktrim(struct sockaddr_in_new *ap)
663 if (ap->sin_addr.s_addr == 0) {
667 cp = (char *)(&ap->sin_addr.s_addr+1);
670 ap->sin_len = cp - (char*)ap + 1;
674 /* Tell the kernel to add, delete or change a route
677 rtioctl(int action, /* RTM_DELETE, etc */
685 struct rt_msghdr w_rtm;
686 struct sockaddr_in w_dst;
687 struct sockaddr_in w_gate;
689 struct sockaddr_in w_mask;
691 struct sockaddr_in_new w_mask;
695 # define PAT " %-10s %s metric=%d flags=%#x"
696 # define ARGS rtm_type_name(action), rtname(dst,mask,gate), metric, flags
699 memset(&w, 0, sizeof(w));
700 w.w_rtm.rtm_msglen = sizeof(w);
701 w.w_rtm.rtm_version = RTM_VERSION;
702 w.w_rtm.rtm_type = action;
703 w.w_rtm.rtm_flags = flags;
704 w.w_rtm.rtm_seq = ++rt_sock_seqno;
705 w.w_rtm.rtm_addrs = RTA_DST|RTA_GATEWAY;
706 if (metric != 0 || action == RTM_CHANGE) {
707 w.w_rtm.rtm_rmx.rmx_hopcount = metric;
708 w.w_rtm.rtm_inits |= RTV_HOPCOUNT;
710 w.w_dst.sin_family = AF_INET;
711 w.w_dst.sin_addr.s_addr = dst;
712 w.w_gate.sin_family = AF_INET;
713 w.w_gate.sin_addr.s_addr = gate;
715 w.w_dst.sin_len = sizeof(w.w_dst);
716 w.w_gate.sin_len = sizeof(w.w_gate);
718 if (mask == HOST_MASK) {
719 w.w_rtm.rtm_flags |= RTF_HOST;
720 w.w_rtm.rtm_msglen -= sizeof(w.w_mask);
722 w.w_rtm.rtm_addrs |= RTA_NETMASK;
723 w.w_mask.sin_addr.s_addr = htonl(mask);
726 if (w.w_mask.sin_len == 0)
727 w.w_mask.sin_len = sizeof(long);
728 w.w_rtm.rtm_msglen -= (sizeof(w.w_mask) - w.w_mask.sin_len);
733 cc = write(rt_sock, &w, w.w_rtm.rtm_msglen);
736 && (action == RTM_CHANGE || action == RTM_DELETE)) {
737 trace_act("route disappeared before" PAT, ARGS);
738 if (action == RTM_CHANGE) {
744 msglog("write(rt_sock)" PAT ": %s", ARGS, strerror(errno));
746 } else if (cc != w.w_rtm.rtm_msglen) {
747 msglog("write(rt_sock) wrote %ld instead of %d for" PAT,
748 cc, w.w_rtm.rtm_msglen, ARGS);
753 trace_misc("write kernel" PAT, ARGS);
759 #define KHASH_SIZE 71 /* should be prime */
760 #define KHASH(a,m) khash_bins[((a) ^ (m)) % KHASH_SIZE]
761 static struct khash {
762 struct khash *k_next;
769 #define KS_DELETE 0x002 /* need to delete the route */
770 #define KS_ADD 0x004 /* add to the kernel */
771 #define KS_CHANGE 0x008 /* tell kernel to change the route */
772 #define KS_DEL_ADD 0x010 /* delete & add to change the kernel */
773 #define KS_STATIC 0x020 /* Static flag in kernel */
774 #define KS_GATEWAY 0x040 /* G flag in kernel */
775 #define KS_DYNAMIC 0x080 /* result of redirect */
776 #define KS_DELETED 0x100 /* already deleted from kernel */
777 #define KS_CHECK 0x200
779 #define K_KEEP_LIM 30
780 time_t k_redirect_time; /* when redirected route 1st seen */
781 } *khash_bins[KHASH_SIZE];
785 kern_find(naddr dst, naddr mask, struct khash ***ppk)
787 struct khash *k, **pk;
789 for (pk = &KHASH(dst,mask); (k = *pk) != 0; pk = &k->k_next) {
790 if (k->k_dst == dst && k->k_mask == mask)
800 kern_add(naddr dst, naddr mask)
802 struct khash *k, **pk;
804 k = kern_find(dst, mask, &pk);
808 k = (struct khash *)rtmalloc(sizeof(*k), "kern_add");
810 memset(k, 0, sizeof(*k));
814 k->k_keep = now.tv_sec;
821 /* If a kernel route has a non-zero metric, check that it is still in the
822 * daemon table, and not deleted by interfaces coming and going.
825 kern_check_static(struct khash *k,
826 struct interface *ifp)
831 if (k->k_metric == 0)
834 memset(&new, 0, sizeof(new));
836 new.rts_gate = k->k_gate;
837 new.rts_router = (ifp != 0) ? ifp->int_addr : loopaddr;
838 new.rts_metric = k->k_metric;
839 new.rts_time = now.tv_sec;
841 rt = rtget(k->k_dst, k->k_mask);
843 if (!(rt->rt_state & RS_STATIC))
844 rtchange(rt, rt->rt_state | RS_STATIC, &new, 0);
846 rtadd(k->k_dst, k->k_mask, RS_STATIC, &new);
851 /* operate on a kernel entry
854 kern_ioctl(struct khash *k,
855 int action, /* RTM_DELETE, etc */
861 k->k_state &= ~KS_DYNAMIC;
862 if (k->k_state & KS_DELETED)
864 k->k_state |= KS_DELETED;
867 k->k_state &= ~KS_DELETED;
870 if (k->k_state & KS_DELETED) {
872 k->k_state &= ~KS_DELETED;
877 rtioctl(action, k->k_dst, k->k_gate, k->k_mask, k->k_metric, flags);
881 /* add a route the kernel told us
884 rtm_add(struct rt_msghdr *rtm,
885 struct rt_addrinfo *info,
889 struct interface *ifp;
893 if (rtm->rtm_flags & RTF_HOST) {
895 } else if (INFO_MASK(info) != 0) {
896 mask = ntohl(S_ADDR(INFO_MASK(info)));
898 msglog("ignore %s without mask", rtm_type_name(rtm->rtm_type));
902 k = kern_add(S_ADDR(INFO_DST(info)), mask);
903 if (k->k_state & KS_NEW)
904 k->k_keep = now.tv_sec+keep;
905 if (INFO_GATE(info) == 0) {
906 trace_act("note %s without gateway",
907 rtm_type_name(rtm->rtm_type));
908 k->k_metric = HOPCNT_INFINITY;
909 } else if (INFO_GATE(info)->sa_family != AF_INET) {
910 trace_act("note %s with gateway AF=%d",
911 rtm_type_name(rtm->rtm_type),
912 INFO_GATE(info)->sa_family);
913 k->k_metric = HOPCNT_INFINITY;
915 k->k_gate = S_ADDR(INFO_GATE(info));
916 k->k_metric = rtm->rtm_rmx.rmx_hopcount;
919 else if (k->k_metric > HOPCNT_INFINITY-1)
920 k->k_metric = HOPCNT_INFINITY-1;
922 k->k_state &= ~(KS_DELETE | KS_ADD | KS_CHANGE | KS_DEL_ADD
923 | KS_DELETED | KS_GATEWAY | KS_STATIC
924 | KS_NEW | KS_CHECK);
925 if (rtm->rtm_flags & RTF_GATEWAY)
926 k->k_state |= KS_GATEWAY;
927 if (rtm->rtm_flags & RTF_STATIC)
928 k->k_state |= KS_STATIC;
930 if (0 != (rtm->rtm_flags & (RTF_DYNAMIC | RTF_MODIFIED))) {
931 if (INFO_AUTHOR(info) != 0
932 && INFO_AUTHOR(info)->sa_family == AF_INET)
933 ifp = iflookup(S_ADDR(INFO_AUTHOR(info)));
937 && (ifp == 0 || !(ifp->int_state & IS_REDIRECT_OK))) {
938 /* Routers are not supposed to listen to redirects,
939 * so delete it if it came via an unknown interface
940 * or the interface does not have special permission.
942 k->k_state &= ~KS_DYNAMIC;
943 k->k_state |= KS_DELETE;
944 LIM_SEC(need_kern, 0);
945 trace_act("mark for deletion redirected %s --> %s"
947 addrname(k->k_dst, k->k_mask, 0),
948 naddr_ntoa(k->k_gate),
949 ifp ? ifp->int_name : "unknown interface");
951 k->k_state |= KS_DYNAMIC;
952 k->k_redirect_time = now.tv_sec;
953 trace_act("accept redirected %s --> %s via %s",
954 addrname(k->k_dst, k->k_mask, 0),
955 naddr_ntoa(k->k_gate),
956 ifp ? ifp->int_name : "unknown interface");
961 /* If it is not a static route, quit until the next comparison
962 * between the kernel and daemon tables, when it will be deleted.
964 if (!(k->k_state & KS_STATIC)) {
965 k->k_state |= KS_DELETE;
966 LIM_SEC(need_kern, k->k_keep);
970 /* Put static routes with real metrics into the daemon table so
971 * they can be advertised.
973 * Find the interface toward the gateway.
975 ifp = iflookup(k->k_gate);
977 msglog("static route %s --> %s impossibly lacks ifp",
978 addrname(S_ADDR(INFO_DST(info)), mask, 0),
979 naddr_ntoa(k->k_gate));
981 kern_check_static(k, ifp);
985 /* deal with packet loss
988 rtm_lose(struct rt_msghdr *rtm,
989 struct rt_addrinfo *info)
991 if (INFO_GATE(info) == 0
992 || INFO_GATE(info)->sa_family != AF_INET) {
993 trace_act("ignore %s without gateway",
994 rtm_type_name(rtm->rtm_type));
999 rdisc_age(S_ADDR(INFO_GATE(info)));
1000 age(S_ADDR(INFO_GATE(info)));
1004 /* Make the gateway slot of an info structure point to something
1005 * useful. If it is not already useful, but it specifies an interface,
1006 * then fill in the sockaddr_in provided and point it there.
1009 get_info_gate(struct sockaddr **sap,
1010 struct sockaddr_in *rsin)
1012 struct sockaddr_dl *sdl = (struct sockaddr_dl *)*sap;
1013 struct interface *ifp;
1017 if ((sdl)->sdl_family == AF_INET)
1019 if ((sdl)->sdl_family != AF_LINK)
1022 ifp = ifwithindex(sdl->sdl_index, 1);
1026 rsin->sin_addr.s_addr = ifp->int_addr;
1028 rsin->sin_len = sizeof(*rsin);
1030 rsin->sin_family = AF_INET;
1031 *sap = (struct sockaddr*)rsin;
1037 /* Clean the kernel table by copying it to the daemon image.
1038 * Eventually the daemon will delete any extra routes.
1043 static char *sysctl_buf;
1044 static size_t sysctl_buf_size = 0;
1048 struct rt_msghdr *rtm;
1049 struct sockaddr_in gate_sin;
1050 struct rt_addrinfo info;
1055 for (i = 0; i < KHASH_SIZE; i++) {
1056 for (k = khash_bins[i]; k != 0; k = k->k_next) {
1057 k->k_state |= KS_CHECK;
1063 mib[2] = 0; /* protocol */
1064 mib[3] = 0; /* wildcard address family */
1065 mib[4] = NET_RT_DUMP;
1066 mib[5] = 0; /* no flags */
1068 if ((needed = sysctl_buf_size) != 0) {
1069 if (sysctl(mib, 6, sysctl_buf,&needed, 0, 0) >= 0)
1071 if (errno != ENOMEM && errno != EFAULT)
1072 BADERR(1,"flush_kern: sysctl(RT_DUMP)");
1076 if (sysctl(mib, 6, 0, &needed, 0, 0) < 0)
1077 BADERR(1,"flush_kern: sysctl(RT_DUMP) estimate");
1078 /* Kludge around the habit of some systems, such as
1079 * BSD/OS 3.1, to not admit how many routes are in the
1080 * kernel, or at least to be quite wrong.
1082 needed += 50*(sizeof(*rtm)+5*sizeof(struct sockaddr));
1083 sysctl_buf = rtmalloc(sysctl_buf_size = needed,
1084 "flush_kern sysctl(RT_DUMP)");
1087 lim = sysctl_buf + needed;
1088 for (next = sysctl_buf; next < lim; next += rtm->rtm_msglen) {
1089 rtm = (struct rt_msghdr *)next;
1090 if (rtm->rtm_msglen == 0) {
1091 msglog("zero length kernel route at "
1092 " %#lx in buffer %#lx before %#lx",
1093 (u_long)rtm, (u_long)sysctl_buf, (u_long)lim);
1098 (struct sockaddr *)(rtm+1),
1099 (struct sockaddr *)(next + rtm->rtm_msglen),
1102 if (INFO_DST(&info) == 0
1103 || INFO_DST(&info)->sa_family != AF_INET)
1106 #if defined (RTF_LLINFO)
1107 /* ignore ARP table entries on systems with a merged route
1110 if (rtm->rtm_flags & RTF_LLINFO)
1113 #if defined(RTF_WASCLONED) && defined(__FreeBSD__)
1114 /* ignore cloned routes
1116 if (rtm->rtm_flags & RTF_WASCLONED)
1120 /* ignore multicast addresses
1122 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info)))))
1125 if (!get_info_gate(&INFO_GATE(&info), &gate_sin))
1128 /* Note static routes and interface routes, and also
1129 * preload the image of the kernel table so that
1130 * we can later clean it, as well as avoid making
1131 * unneeded changes. Keep the old kernel routes for a
1132 * few seconds to allow a RIP or router-discovery
1133 * response to be heard.
1135 rtm_add(rtm,&info,MIN_WAITTIME);
1138 for (i = 0; i < KHASH_SIZE; i++) {
1139 for (k = khash_bins[i]; k != 0; k = k->k_next) {
1140 if (k->k_state & KS_CHECK) {
1141 msglog("%s --> %s disappeared from kernel",
1142 addrname(k->k_dst, k->k_mask, 0),
1143 naddr_ntoa(k->k_gate));
1144 del_static(k->k_dst, k->k_mask, k->k_gate, 1);
1151 /* Listen to announcements from the kernel
1157 struct interface *ifp;
1158 struct sockaddr_in gate_sin;
1162 struct rt_msghdr rtm;
1163 struct sockaddr addrs[RTAX_MAX];
1165 struct if_msghdr ifm;
1167 char str[100], *strp;
1168 struct rt_addrinfo info;
1172 cc = read(rt_sock, &m, sizeof(m));
1174 if (cc < 0 && errno != EWOULDBLOCK)
1175 LOGERR("read(rt_sock)");
1179 if (m.r.rtm.rtm_version != RTM_VERSION) {
1180 msglog("bogus routing message version %d",
1181 m.r.rtm.rtm_version);
1185 /* Ignore our own results.
1187 if (m.r.rtm.rtm_type <= RTM_CHANGE
1188 && m.r.rtm.rtm_pid == mypid) {
1189 static int complained = 0;
1191 msglog("receiving our own change messages");
1197 if (m.r.rtm.rtm_type == RTM_IFINFO
1198 || m.r.rtm.rtm_type == RTM_NEWADDR
1199 || m.r.rtm.rtm_type == RTM_DELADDR) {
1200 ifp = ifwithindex(m.ifm.ifm_index,
1201 m.r.rtm.rtm_type != RTM_DELADDR);
1203 trace_act("note %s with flags %#x"
1204 " for unknown interface index #%d",
1205 rtm_type_name(m.r.rtm.rtm_type),
1209 trace_act("note %s with flags %#x for %s",
1210 rtm_type_name(m.r.rtm.rtm_type),
1214 /* After being informed of a change to an interface,
1215 * check them all now if the check would otherwise
1216 * be a long time from now, if the interface is
1217 * not known, or if the interface has been turned
1220 if (ifinit_timer.tv_sec-now.tv_sec>=CHECK_BAD_INTERVAL
1222 || ((ifp->int_if_flags ^ m.ifm.ifm_flags)
1224 ifinit_timer.tv_sec = now.tv_sec;
1228 if (m.r.rtm.rtm_type == RTM_OIFINFO)
1229 continue; /* ignore compat message */
1232 strcpy(str, rtm_type_name(m.r.rtm.rtm_type));
1233 strp = &str[strlen(str)];
1234 if (m.r.rtm.rtm_type <= RTM_CHANGE)
1235 strp += sprintf(strp," from pid %d",m.r.rtm.rtm_pid);
1237 rt_xaddrs(&info, m.r.addrs, &m.r.addrs[RTAX_MAX],
1240 if (INFO_DST(&info) == 0) {
1241 trace_act("ignore %s without dst", str);
1245 if (INFO_DST(&info)->sa_family != AF_INET) {
1246 trace_act("ignore %s for AF %d", str,
1247 INFO_DST(&info)->sa_family);
1251 mask = ((INFO_MASK(&info) != 0)
1252 ? ntohl(S_ADDR(INFO_MASK(&info)))
1253 : (m.r.rtm.rtm_flags & RTF_HOST)
1255 : std_mask(S_ADDR(INFO_DST(&info))));
1257 strp += sprintf(strp, ": %s",
1258 addrname(S_ADDR(INFO_DST(&info)), mask, 0));
1260 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) {
1261 trace_act("ignore multicast %s", str);
1265 #if defined(RTF_LLINFO)
1266 if (m.r.rtm.rtm_flags & RTF_LLINFO) {
1267 trace_act("ignore ARP %s", str);
1272 #if defined(RTF_WASCLONED) && defined(__FreeBSD__)
1273 if (m.r.rtm.rtm_flags & RTF_WASCLONED) {
1274 trace_act("ignore cloned %s", str);
1279 if (get_info_gate(&INFO_GATE(&info), &gate_sin)) {
1280 gate = S_ADDR(INFO_GATE(&info));
1281 strp += sprintf(strp, " --> %s", naddr_ntoa(gate));
1286 if (INFO_AUTHOR(&info) != 0)
1287 strp += sprintf(strp, " by authority of %s",
1288 saddr_ntoa(INFO_AUTHOR(&info)));
1290 switch (m.r.rtm.rtm_type) {
1294 if (m.r.rtm.rtm_errno != 0) {
1295 trace_act("ignore %s with \"%s\" error",
1296 str, strerror(m.r.rtm.rtm_errno));
1298 trace_act("%s", str);
1299 rtm_add(&m.r.rtm,&info,0);
1304 if (m.r.rtm.rtm_errno != 0
1305 && m.r.rtm.rtm_errno != ESRCH) {
1306 trace_act("ignore %s with \"%s\" error",
1307 str, strerror(m.r.rtm.rtm_errno));
1309 trace_act("%s", str);
1310 del_static(S_ADDR(INFO_DST(&info)), mask,
1316 trace_act("%s", str);
1317 rtm_lose(&m.r.rtm,&info);
1321 trace_act("ignore %s", str);
1328 /* after aggregating, note routes that belong in the kernel
1331 kern_out(struct ag_info *ag)
1336 /* Do not install bad routes if they are not already present.
1337 * This includes routes that had RS_NET_SYN for interfaces that
1340 if (ag->ag_metric == HOPCNT_INFINITY) {
1341 k = kern_find(htonl(ag->ag_dst_h), ag->ag_mask, 0);
1345 k = kern_add(htonl(ag->ag_dst_h), ag->ag_mask);
1348 if (k->k_state & KS_NEW) {
1349 /* will need to add new entry to the kernel table */
1350 k->k_state = KS_ADD;
1351 if (ag->ag_state & AGS_GATEWAY)
1352 k->k_state |= KS_GATEWAY;
1353 k->k_gate = ag->ag_gate;
1354 k->k_metric = ag->ag_metric;
1358 if (k->k_state & KS_STATIC)
1361 /* modify existing kernel entry if necessary */
1362 if (k->k_gate != ag->ag_gate
1363 || k->k_metric != ag->ag_metric) {
1364 /* Must delete bad interface routes etc. to change them. */
1365 if (k->k_metric == HOPCNT_INFINITY)
1366 k->k_state |= KS_DEL_ADD;
1367 k->k_gate = ag->ag_gate;
1368 k->k_metric = ag->ag_metric;
1369 k->k_state |= KS_CHANGE;
1372 /* If the daemon thinks the route should exist, forget
1373 * about any redirections.
1374 * If the daemon thinks the route should exist, eventually
1375 * override manual intervention by the operator.
1377 if ((k->k_state & (KS_DYNAMIC | KS_DELETED)) != 0) {
1378 k->k_state &= ~KS_DYNAMIC;
1379 k->k_state |= (KS_ADD | KS_DEL_ADD);
1382 if ((k->k_state & KS_GATEWAY)
1383 && !(ag->ag_state & AGS_GATEWAY)) {
1384 k->k_state &= ~KS_GATEWAY;
1385 k->k_state |= (KS_ADD | KS_DEL_ADD);
1386 } else if (!(k->k_state & KS_GATEWAY)
1387 && (ag->ag_state & AGS_GATEWAY)) {
1388 k->k_state |= KS_GATEWAY;
1389 k->k_state |= (KS_ADD | KS_DEL_ADD);
1392 /* Deleting-and-adding is necessary to change aspects of a route.
1393 * Just delete instead of deleting and then adding a bad route.
1394 * Otherwise, we want to keep the route in the kernel.
1396 if (k->k_metric == HOPCNT_INFINITY
1397 && (k->k_state & KS_DEL_ADD))
1398 k->k_state |= KS_DELETE;
1400 k->k_state &= ~KS_DELETE;
1407 walk_kern(struct radix_node *rn,
1408 struct walkarg *argp UNUSED)
1410 #define RT ((struct rt_entry *)rn)
1415 /* Do not install synthetic routes */
1416 if (RT->rt_state & RS_NET_SYN)
1419 if (!(RT->rt_state & RS_IF)) {
1420 /* This is an ordinary route, not for an interface.
1423 /* aggregate, ordinary good routes without regard to
1427 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE);
1429 /* Do not install host routes directly to hosts, to avoid
1430 * interfering with ARP entries in the kernel table.
1433 && ntohl(RT->rt_dst) == RT->rt_gate)
1437 /* This is an interface route.
1438 * Do not install routes for "external" remote interfaces.
1440 if (RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_EXTERNAL))
1443 /* Interfaces should override received routes.
1446 ags |= (AGS_IF | AGS_CORS_GATE);
1448 /* If it is not an interface, or an alias for an interface,
1449 * it must be a "gateway."
1451 * If it is a "remote" interface, it is also a "gateway" to
1452 * the kernel if is not an alias.
1455 || (RT->rt_ifp->int_state & IS_REMOTE))
1456 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE);
1459 /* If RIP is off and IRDP is on, let the route to the discovered
1460 * route suppress any RIP routes. Eventually the RIP routes
1461 * will time-out and be deleted. This reaches the steady-state
1464 if ((RT->rt_state & RS_RDISC) && rip_sock < 0)
1465 ags |= AGS_CORS_GATE;
1467 metric = RT->rt_metric;
1468 if (metric == HOPCNT_INFINITY) {
1469 /* if the route is dead, so try hard to aggregate. */
1470 pref = HOPCNT_INFINITY;
1471 ags |= (AGS_FINE_GATE | AGS_SUPPRESS);
1472 ags &= ~(AGS_IF | AGS_CORS_GATE);
1475 ag_check(RT->rt_dst, RT->rt_mask, RT->rt_gate, 0,
1476 metric,pref, 0, 0, ags, kern_out);
1482 /* Update the kernel table to match the daemon table.
1488 struct khash *k, **pk;
1491 need_kern = age_timer;
1493 /* Walk daemon table, updating the copy of the kernel table.
1495 (void)rn_walktree(rhead, walk_kern, 0);
1496 ag_flush(0,0,kern_out);
1498 for (i = 0; i < KHASH_SIZE; i++) {
1499 for (pk = &khash_bins[i]; (k = *pk) != 0; ) {
1500 /* Do not touch static routes */
1501 if (k->k_state & KS_STATIC) {
1502 kern_check_static(k,0);
1507 /* check hold on routes deleted by the operator */
1508 if (k->k_keep > now.tv_sec) {
1509 /* ensure we check when the hold is over */
1510 LIM_SEC(need_kern, k->k_keep);
1511 /* mark for the next cycle */
1512 k->k_state |= KS_DELETE;
1517 if ((k->k_state & KS_DELETE)
1518 && !(k->k_state & KS_DYNAMIC)) {
1519 kern_ioctl(k, RTM_DELETE, 0);
1525 if (k->k_state & KS_DEL_ADD)
1526 kern_ioctl(k, RTM_DELETE, 0);
1528 if (k->k_state & KS_ADD) {
1529 kern_ioctl(k, RTM_ADD,
1530 ((0 != (k->k_state & (KS_GATEWAY
1532 ? RTF_GATEWAY : 0));
1533 } else if (k->k_state & KS_CHANGE) {
1534 kern_ioctl(k, RTM_CHANGE,
1535 ((0 != (k->k_state & (KS_GATEWAY
1537 ? RTF_GATEWAY : 0));
1539 k->k_state &= ~(KS_ADD|KS_CHANGE|KS_DEL_ADD);
1541 /* Mark this route to be deleted in the next cycle.
1542 * This deletes routes that disappear from the
1543 * daemon table, since the normal aging code
1544 * will clear the bit for routes that have not
1545 * disappeared from the daemon table.
1547 k->k_state |= KS_DELETE;
1554 /* Delete a static route in the image of the kernel table.
1557 del_static(naddr dst,
1563 struct rt_entry *rt;
1565 /* Just mark it in the table to be deleted next time the kernel
1567 * If it has already been deleted, mark it as such, and set its
1568 * keep-timer so that it will not be deleted again for a while.
1569 * This lets the operator delete a route added by the daemon
1570 * and add a replacement.
1572 k = kern_find(dst, mask, 0);
1573 if (k != 0 && (gate == 0 || k->k_gate == gate)) {
1574 k->k_state &= ~(KS_STATIC | KS_DYNAMIC | KS_CHECK);
1575 k->k_state |= KS_DELETE;
1577 k->k_state |= KS_DELETED;
1578 k->k_keep = now.tv_sec + K_KEEP_LIM;
1582 rt = rtget(dst, mask);
1583 if (rt != 0 && (rt->rt_state & RS_STATIC))
1588 /* Delete all routes generated from ICMP Redirects that use a given gateway,
1589 * as well as old redirected routes.
1592 del_redirects(naddr bad_gate,
1599 for (i = 0; i < KHASH_SIZE; i++) {
1600 for (k = khash_bins[i]; k != 0; k = k->k_next) {
1601 if (!(k->k_state & KS_DYNAMIC)
1602 || (k->k_state & KS_STATIC))
1605 if (k->k_gate != bad_gate
1606 && k->k_redirect_time > old
1610 k->k_state |= KS_DELETE;
1611 k->k_state &= ~KS_DYNAMIC;
1612 need_kern.tv_sec = now.tv_sec;
1613 trace_act("mark redirected %s --> %s for deletion",
1614 addrname(k->k_dst, k->k_mask, 0),
1615 naddr_ntoa(k->k_gate));
1621 /* Start the daemon tables.
1623 extern int max_keylen;
1631 /* Initialize the radix trees */
1632 max_keylen = sizeof(struct sockaddr_in);
1634 rn_inithead((void**)&rhead, 32);
1636 /* mark all of the slots in the table free */
1637 ag_avail = ag_slots;
1638 for (ag = ag_slots, i = 1; i < NUM_AG_SLOTS; i++) {
1645 #ifdef _HAVE_SIN_LEN
1646 static struct sockaddr_in dst_sock = {sizeof(dst_sock), AF_INET, 0, {0}, {0}};
1647 static struct sockaddr_in mask_sock = {sizeof(mask_sock), AF_INET, 0, {0}, {0}};
1649 static struct sockaddr_in_new dst_sock = {_SIN_ADDR_SIZE, AF_INET};
1650 static struct sockaddr_in_new mask_sock = {_SIN_ADDR_SIZE, AF_INET};
1655 set_need_flash(void)
1659 /* Do not send the flash update immediately. Wait a little
1660 * while to hear from other routers.
1662 no_flash.tv_sec = now.tv_sec + MIN_WAITTIME;
1667 /* Get a particular routing table entry
1670 rtget(naddr dst, naddr mask)
1672 struct rt_entry *rt;
1674 dst_sock.sin_addr.s_addr = dst;
1675 mask_sock.sin_addr.s_addr = htonl(mask);
1676 masktrim(&mask_sock);
1677 rt = (struct rt_entry *)rhead->rnh_lookup(&dst_sock,&mask_sock,rhead);
1679 || rt->rt_dst != dst
1680 || rt->rt_mask != mask)
1687 /* Find a route to dst as the kernel would.
1692 dst_sock.sin_addr.s_addr = dst;
1693 return (struct rt_entry *)rhead->rnh_matchaddr(&dst_sock, rhead);
1697 /* add a route to the table
1702 u_int state, /* rt_state for the entry */
1703 struct rt_spare *new)
1705 struct rt_entry *rt;
1708 struct rt_spare *rts;
1710 rt = (struct rt_entry *)rtmalloc(sizeof (*rt), "rtadd");
1711 memset(rt, 0, sizeof(*rt));
1712 for (rts = rt->rt_spares, i = NUM_SPARES; i != 0; i--, rts++)
1713 rts->rts_metric = HOPCNT_INFINITY;
1715 rt->rt_nodes->rn_key = (caddr_t)&rt->rt_dst_sock;
1717 rt->rt_dst_sock.sin_family = AF_INET;
1718 #ifdef _HAVE_SIN_LEN
1719 rt->rt_dst_sock.sin_len = dst_sock.sin_len;
1721 if (mask != HOST_MASK) {
1722 smask = std_mask(dst);
1723 if ((smask & ~mask) == 0 && mask > smask)
1726 mask_sock.sin_addr.s_addr = htonl(mask);
1727 masktrim(&mask_sock);
1729 rt->rt_state = state;
1730 rt->rt_spares[0] = *new;
1731 rt->rt_time = now.tv_sec;
1732 rt->rt_poison_metric = HOPCNT_INFINITY;
1733 rt->rt_seqno = update_seqno;
1735 if (++total_routes == MAX_ROUTES)
1736 msglog("have maximum (%d) routes", total_routes);
1738 trace_add_del("Add", rt);
1740 need_kern.tv_sec = now.tv_sec;
1743 if (0 == rhead->rnh_addaddr(&rt->rt_dst_sock, &mask_sock,
1744 rhead, rt->rt_nodes)) {
1745 msglog("rnh_addaddr() failed for %s mask=%#lx",
1746 naddr_ntoa(dst), (u_long)mask);
1752 /* notice a changed route
1755 rtchange(struct rt_entry *rt,
1756 u_int state, /* new state bits */
1757 struct rt_spare *new,
1760 if (rt->rt_metric != new->rts_metric) {
1761 /* Fix the kernel immediately if it seems the route
1762 * has gone bad, since there may be a working route that
1763 * aggregates this route.
1765 if (new->rts_metric == HOPCNT_INFINITY) {
1766 need_kern.tv_sec = now.tv_sec;
1767 if (new->rts_time >= now.tv_sec - EXPIRE_TIME)
1768 new->rts_time = now.tv_sec - EXPIRE_TIME;
1770 rt->rt_seqno = update_seqno;
1774 if (rt->rt_gate != new->rts_gate) {
1775 need_kern.tv_sec = now.tv_sec;
1776 rt->rt_seqno = update_seqno;
1780 state |= (rt->rt_state & RS_SUBNET);
1782 /* Keep various things from deciding ageless routes are stale.
1784 if (!AGE_RT(state, new->rts_ifp))
1785 new->rts_time = now.tv_sec;
1788 trace_change(rt, state, new,
1789 label ? label : "Chg ");
1791 rt->rt_state = state;
1792 rt->rt_spares[0] = *new;
1796 /* check for a better route among the spares
1798 static struct rt_spare *
1799 rts_better(struct rt_entry *rt)
1801 struct rt_spare *rts, *rts1;
1804 /* find the best alternative among the spares */
1805 rts = rt->rt_spares+1;
1806 for (i = NUM_SPARES, rts1 = rts+1; i > 2; i--, rts1++) {
1807 if (BETTER_LINK(rt,rts1,rts))
1815 /* switch to a backup route
1818 rtswitch(struct rt_entry *rt,
1819 struct rt_spare *rts)
1821 struct rt_spare swap;
1825 /* Do not change permanent routes */
1826 if (0 != (rt->rt_state & (RS_MHOME | RS_STATIC | RS_RDISC
1827 | RS_NET_SYN | RS_IF)))
1830 /* find the best alternative among the spares */
1832 rts = rts_better(rt);
1834 /* Do not bother if it is not worthwhile.
1836 if (!BETTER_LINK(rt, rts, rt->rt_spares))
1839 swap = rt->rt_spares[0];
1840 (void)sprintf(label, "Use #%d", (int)(rts - rt->rt_spares));
1841 rtchange(rt, rt->rt_state & ~(RS_NET_SYN | RS_RDISC), rts, label);
1842 if (swap.rts_metric == HOPCNT_INFINITY) {
1851 rtdelete(struct rt_entry *rt)
1857 trace_add_del("Del", rt);
1859 k = kern_find(rt->rt_dst, rt->rt_mask, 0);
1861 k->k_state |= KS_DELETE;
1862 need_kern.tv_sec = now.tv_sec;
1865 dst_sock.sin_addr.s_addr = rt->rt_dst;
1866 mask_sock.sin_addr.s_addr = htonl(rt->rt_mask);
1867 masktrim(&mask_sock);
1868 if (rt != (struct rt_entry *)rhead->rnh_deladdr(&dst_sock, &mask_sock,
1870 msglog("rnh_deladdr() failed");
1879 rts_delete(struct rt_entry *rt,
1880 struct rt_spare *rts)
1882 trace_upslot(rt, rts, &rts_empty);
1887 /* Get rid of a bad route, and try to switch to a replacement.
1890 rtbad(struct rt_entry *rt)
1892 struct rt_spare new;
1894 /* Poison the route */
1895 new = rt->rt_spares[0];
1896 new.rts_metric = HOPCNT_INFINITY;
1897 rtchange(rt, rt->rt_state & ~(RS_IF | RS_LOCAL | RS_STATIC), &new, 0);
1902 /* Junk a RS_NET_SYN or RS_LOCAL route,
1903 * unless it is needed by another interface.
1906 rtbad_sub(struct rt_entry *rt)
1908 struct interface *ifp, *ifp1;
1909 struct intnet *intnetp;
1916 if (rt->rt_state & RS_LOCAL) {
1917 /* Is this the route through loopback for the interface?
1918 * If so, see if it is used by any other interfaces, such
1919 * as a point-to-point interface with the same local address.
1921 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
1922 /* Retain it if another interface needs it.
1924 if (ifp->int_addr == rt->rt_ifp->int_addr) {
1933 if (!(state & RS_LOCAL)) {
1934 /* Retain RIPv1 logical network route if there is another
1935 * interface that justifies it.
1937 if (rt->rt_state & RS_NET_SYN) {
1938 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
1939 if ((ifp->int_state & IS_NEED_NET_SYN)
1940 && rt->rt_mask == ifp->int_std_mask
1941 && rt->rt_dst == ifp->int_std_addr) {
1942 state |= RS_NET_SYN;
1949 /* or if there is an authority route that needs it. */
1950 for (intnetp = intnets;
1952 intnetp = intnetp->intnet_next) {
1953 if (intnetp->intnet_addr == rt->rt_dst
1954 && intnetp->intnet_mask == rt->rt_mask) {
1955 state |= (RS_NET_SYN | RS_NET_INT);
1961 if (ifp1 != 0 || (state & RS_NET_SYN)) {
1962 struct rt_spare new = rt->rt_spares[0];
1964 rtchange(rt, ((rt->rt_state & ~(RS_NET_SYN|RS_LOCAL)) | state),
1972 /* Called while walking the table looking for sick interfaces
1973 * or after a time change.
1977 walk_bad(struct radix_node *rn,
1978 struct walkarg *argp UNUSED)
1980 #define RT ((struct rt_entry *)rn)
1981 struct rt_spare *rts;
1985 /* fix any spare routes through the interface
1987 rts = RT->rt_spares;
1988 for (i = NUM_SPARES; i != 1; i--) {
1990 if (rts->rts_metric < HOPCNT_INFINITY
1991 && (rts->rts_ifp == 0
1992 || (rts->rts_ifp->int_state & IS_BROKE)))
1993 rts_delete(RT, rts);
1996 /* Deal with the main route
1998 /* finished if it has been handled before or if its interface is ok
2000 if (RT->rt_ifp == 0 || !(RT->rt_ifp->int_state & IS_BROKE))
2003 /* Bad routes for other than interfaces are easy.
2005 if (0 == (RT->rt_state & (RS_IF | RS_NET_SYN | RS_LOCAL))) {
2016 /* Check the age of an individual route.
2020 walk_age(struct radix_node *rn,
2021 struct walkarg *argp UNUSED)
2023 #define RT ((struct rt_entry *)rn)
2024 struct interface *ifp;
2025 struct rt_spare *rts;
2029 /* age all of the spare routes, including the primary route
2032 rts = RT->rt_spares;
2033 for (i = NUM_SPARES; i != 0; i--, rts++) {
2036 if (i == NUM_SPARES) {
2037 if (!AGE_RT(RT->rt_state, ifp)) {
2038 /* Keep various things from deciding ageless
2041 rts->rts_time = now.tv_sec;
2045 /* forget RIP routes after RIP has been turned off.
2053 /* age failing routes
2055 if (age_bad_gate == rts->rts_gate
2056 && rts->rts_time >= now_stale) {
2057 rts->rts_time -= SUPPLY_INTERVAL;
2060 /* trash the spare routes when they go bad */
2061 if (rts->rts_metric < HOPCNT_INFINITY
2062 && now_garbage > rts->rts_time
2064 rts_delete(RT, rts);
2068 /* finished if the active route is still fresh */
2069 if (now_stale <= RT->rt_time)
2072 /* try to switch to an alternative */
2075 /* Delete a dead route after it has been publically mourned. */
2076 if (now_garbage > RT->rt_time) {
2081 /* Start poisoning a bad route before deleting it. */
2082 if (now.tv_sec - RT->rt_time > EXPIRE_TIME) {
2083 struct rt_spare new = RT->rt_spares[0];
2084 new.rts_metric = HOPCNT_INFINITY;
2085 rtchange(RT, RT->rt_state, &new, 0);
2091 /* Watch for dead routes and interfaces.
2096 struct interface *ifp;
2099 /* If not listening to RIP, there is no need to age the routes in
2102 age_timer.tv_sec = (now.tv_sec
2103 + ((rip_sock < 0) ? NEVER : SUPPLY_INTERVAL));
2105 /* Check for dead IS_REMOTE interfaces by timing their
2108 for (ifp = ifnet; ifp; ifp = ifp->int_next) {
2109 if (!(ifp->int_state & IS_REMOTE))
2112 /* ignore unreachable remote interfaces */
2113 if (!check_remote(ifp))
2116 /* Restore remote interface that has become reachable
2118 if (ifp->int_state & IS_BROKE)
2119 if_ok(ifp, "remote ");
2121 if (ifp->int_act_time != NEVER
2122 && now.tv_sec - ifp->int_act_time > EXPIRE_TIME) {
2123 msglog("remote interface %s to %s timed out after"
2126 naddr_ntoa(ifp->int_dstaddr),
2127 (now.tv_sec - ifp->int_act_time)/60,
2128 (now.tv_sec - ifp->int_act_time)%60);
2132 /* If we have not heard from the other router
2135 if (now.tv_sec >= ifp->int_query_time) {
2136 ifp->int_query_time = NEVER;
2142 age_bad_gate = bad_gate;
2143 (void)rn_walktree(rhead, walk_age, 0);
2145 /* delete old redirected routes to keep the kernel table small
2146 * and prevent blackholes
2148 del_redirects(bad_gate, now.tv_sec-STALE_TIME);
2150 /* Update the kernel routing table. */
2153 /* poke reticent remote gateways */