xref: /dragonfly/contrib/dhcpcd/src/route.c (revision f984587a)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * dhcpcd - route management
4  * Copyright (c) 2006-2023 Roy Marples <roy@marples.name>
5  * All rights reserved
6 
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <assert.h>
30 #include <ctype.h>
31 #include <errno.h>
32 #include <stdbool.h>
33 #include <stddef.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <unistd.h>
37 
38 #include "config.h"
39 #include "common.h"
40 #include "dhcpcd.h"
41 #include "if.h"
42 #include "if-options.h"
43 #include "ipv4.h"
44 #include "ipv4ll.h"
45 #include "ipv6.h"
46 #include "logerr.h"
47 #include "route.h"
48 #include "sa.h"
49 
50 /* Needed for NetBSD-6, 7 and 8. */
51 #ifndef RB_TREE_FOREACH_SAFE
52 #ifndef RB_TREE_PREV
53 #define RB_TREE_NEXT(T, N) rb_tree_iterate((T), (N), RB_DIR_RIGHT)
54 #define RB_TREE_PREV(T, N) rb_tree_iterate((T), (N), RB_DIR_LEFT)
55 #endif
56 #define RB_TREE_FOREACH_SAFE(N, T, S) \
57     for ((N) = RB_TREE_MIN(T); \
58         (N) && ((S) = RB_TREE_NEXT((T), (N)), 1); \
59         (N) = (S))
60 #define RB_TREE_FOREACH_REVERSE_SAFE(N, T, S) \
61     for ((N) = RB_TREE_MAX(T); \
62         (N) && ((S) = RB_TREE_PREV((T), (N)), 1); \
63         (N) = (S))
64 #endif
65 
66 #ifdef RT_FREE_ROUTE_TABLE_STATS
67 static size_t croutes;
68 static size_t nroutes;
69 static size_t froutes;
70 static size_t mroutes;
71 #endif
72 
73 static void
74 rt_maskedaddr(struct sockaddr *dst,
75 	const struct sockaddr *addr, const struct sockaddr *netmask)
76 {
77 	const char *addrp = addr->sa_data, *netmaskp = netmask->sa_data;
78 	char *dstp = dst->sa_data;
79 	const char *addre = (char *)dst + sa_len(addr);
80 	const char *netmaske = (char *)dst + MIN(sa_len(addr), sa_len(netmask));
81 
82 	dst->sa_family = addr->sa_family;
83 #ifdef HAVE_SA_LEN
84 	dst->sa_len = addr->sa_len;
85 #endif
86 
87 	if (sa_is_unspecified(netmask)) {
88 		if (addre > dstp)
89 			memcpy(dstp, addrp, (size_t)(addre - dstp));
90 		return;
91 	}
92 
93 	while (dstp < netmaske)
94 		*dstp++ = *addrp++ & *netmaskp++;
95 	if (dstp < addre)
96 		memset(dstp, 0, (size_t)(addre - dstp));
97 }
98 
99 /*
100  * On some systems, host routes have no need for a netmask.
101  * However DHCP specifies host routes using an all-ones netmask.
102  * This handy function allows easy comparison when the two
103  * differ.
104  */
105 static int
106 rt_cmp_netmask(const struct rt *rt1, const struct rt *rt2)
107 {
108 
109 	if (rt1->rt_flags & RTF_HOST && rt2->rt_flags & RTF_HOST)
110 		return 0;
111 	return sa_cmp(&rt1->rt_netmask, &rt2->rt_netmask);
112 }
113 
114 int
115 rt_cmp_dest(const struct rt *rt1, const struct rt *rt2)
116 {
117 	union sa_ss ma1 = { .sa.sa_family = AF_UNSPEC };
118 	union sa_ss ma2 = { .sa.sa_family = AF_UNSPEC };
119 	int c;
120 
121 	rt_maskedaddr(&ma1.sa, &rt1->rt_dest, &rt1->rt_netmask);
122 	rt_maskedaddr(&ma2.sa, &rt2->rt_dest, &rt2->rt_netmask);
123 	c = sa_cmp(&ma1.sa, &ma2.sa);
124 	if (c != 0)
125 		return c;
126 
127 	return rt_cmp_netmask(rt1, rt2);
128 }
129 
130 static int
131 rt_compare_os(__unused void *context, const void *node1, const void *node2)
132 {
133 	const struct rt *rt1 = node1, *rt2 = node2;
134 	int c;
135 
136 	/* Sort by masked destination. */
137 	c = rt_cmp_dest(rt1, rt2);
138 	if (c != 0)
139 		return c;
140 
141 #ifdef HAVE_ROUTE_METRIC
142 	c = (int)(rt1->rt_ifp->metric - rt2->rt_ifp->metric);
143 #endif
144 	return c;
145 }
146 
147 static int
148 rt_compare_list(__unused void *context, const void *node1, const void *node2)
149 {
150 	const struct rt *rt1 = node1, *rt2 = node2;
151 
152 	if (rt1->rt_order > rt2->rt_order)
153 		return 1;
154 	if (rt1->rt_order < rt2->rt_order)
155 		return -1;
156 	return 0;
157 }
158 
159 static int
160 rt_compare_proto(void *context, const void *node1, const void *node2)
161 {
162 	const struct rt *rt1 = node1, *rt2 = node2;
163 	int c;
164 	struct interface *ifp1, *ifp2;
165 
166 	assert(rt1->rt_ifp != NULL);
167 	assert(rt2->rt_ifp != NULL);
168 	ifp1 = rt1->rt_ifp;
169 	ifp2 = rt2->rt_ifp;
170 
171 	/* Prefer interfaces with a carrier. */
172 	c = ifp1->carrier - ifp2->carrier;
173 	if (c != 0)
174 		return -c;
175 
176 	/* Prefer roaming over non roaming if both carriers are down. */
177 	if (ifp1->carrier == LINK_DOWN && ifp2->carrier == LINK_DOWN) {
178 		bool roam1 = if_roaming(ifp1);
179 		bool roam2 = if_roaming(ifp2);
180 
181 		if (roam1 != roam2)
182 			return roam1 ? 1 : -1;
183 	}
184 
185 #ifdef INET
186 	/* IPv4LL routes always come last */
187 	if (rt1->rt_dflags & RTDF_IPV4LL && !(rt2->rt_dflags & RTDF_IPV4LL))
188 		return -1;
189 	else if (!(rt1->rt_dflags & RTDF_IPV4LL) && rt2->rt_dflags & RTDF_IPV4LL)
190 		return 1;
191 #endif
192 
193 	/* Lower metric interfaces come first. */
194 	c = (int)(ifp1->metric - ifp2->metric);
195 	if (c != 0)
196 		return c;
197 
198 	/* Finally the order in which the route was given to us. */
199 	return rt_compare_list(context, rt1, rt2);
200 }
201 
202 static const rb_tree_ops_t rt_compare_os_ops = {
203 	.rbto_compare_nodes = rt_compare_os,
204 	.rbto_compare_key = rt_compare_os,
205 	.rbto_node_offset = offsetof(struct rt, rt_tree),
206 	.rbto_context = NULL
207 };
208 
209 const rb_tree_ops_t rt_compare_list_ops = {
210 	.rbto_compare_nodes = rt_compare_list,
211 	.rbto_compare_key = rt_compare_list,
212 	.rbto_node_offset = offsetof(struct rt, rt_tree),
213 	.rbto_context = NULL
214 };
215 
216 const rb_tree_ops_t rt_compare_proto_ops = {
217 	.rbto_compare_nodes = rt_compare_proto,
218 	.rbto_compare_key = rt_compare_proto,
219 	.rbto_node_offset = offsetof(struct rt, rt_tree),
220 	.rbto_context = NULL
221 };
222 
223 #ifdef RT_FREE_ROUTE_TABLE
224 static int
225 rt_compare_free(__unused void *context, const void *node1, const void *node2)
226 {
227 
228 	return node1 == node2 ? 0 : node1 < node2 ? -1 : 1;
229 }
230 
231 static const rb_tree_ops_t rt_compare_free_ops = {
232 	.rbto_compare_nodes = rt_compare_free,
233 	.rbto_compare_key = rt_compare_free,
234 	.rbto_node_offset = offsetof(struct rt, rt_tree),
235 	.rbto_context = NULL
236 };
237 #endif
238 
239 void
240 rt_init(struct dhcpcd_ctx *ctx)
241 {
242 
243 	rb_tree_init(&ctx->routes, &rt_compare_os_ops);
244 #ifdef RT_FREE_ROUTE_TABLE
245 	rb_tree_init(&ctx->froutes, &rt_compare_free_ops);
246 #endif
247 }
248 
249 bool
250 rt_is_default(const struct rt *rt)
251 {
252 
253 	return sa_is_unspecified(&rt->rt_dest) &&
254 	    sa_is_unspecified(&rt->rt_netmask);
255 }
256 
257 static void
258 rt_desc(const char *cmd, const struct rt *rt)
259 {
260 	char dest[INET_MAX_ADDRSTRLEN], gateway[INET_MAX_ADDRSTRLEN];
261 	int prefix;
262 	const char *ifname;
263 	bool gateway_unspec;
264 
265 	assert(cmd != NULL);
266 	assert(rt != NULL);
267 
268 	sa_addrtop(&rt->rt_dest, dest, sizeof(dest));
269 	prefix = sa_toprefix(&rt->rt_netmask);
270 	sa_addrtop(&rt->rt_gateway, gateway, sizeof(gateway));
271 	gateway_unspec = sa_is_unspecified(&rt->rt_gateway);
272 	ifname = rt->rt_ifp == NULL ? "(null)" : rt->rt_ifp->name;
273 
274 	if (rt->rt_flags & RTF_HOST) {
275 		if (gateway_unspec)
276 			loginfox("%s: %s host route to %s",
277 			    ifname, cmd, dest);
278 		else
279 			loginfox("%s: %s host route to %s via %s",
280 			    ifname, cmd, dest, gateway);
281 	} else if (rt_is_default(rt)) {
282 		if (gateway_unspec)
283 			loginfox("%s: %s default route",
284 			    ifname, cmd);
285 		else
286 			loginfox("%s: %s default route via %s",
287 			    ifname, cmd, gateway);
288 	} else if (gateway_unspec)
289 		loginfox("%s: %s%s route to %s/%d",
290 		    ifname, cmd,
291 		    rt->rt_flags & RTF_REJECT ? " reject" : "",
292 		    dest, prefix);
293 	else
294 		loginfox("%s: %s%s route to %s/%d via %s",
295 		    ifname, cmd,
296 		    rt->rt_flags & RTF_REJECT ? " reject" : "",
297 		    dest, prefix, gateway);
298 }
299 
300 void
301 rt_headclear0(struct dhcpcd_ctx *ctx, rb_tree_t *rts, int af)
302 {
303 	struct rt *rt, *rtn;
304 
305 	if (rts == NULL)
306 		return;
307 	assert(ctx != NULL);
308 #ifdef RT_FREE_ROUTE_TABLE
309 	assert(&ctx->froutes != rts);
310 #endif
311 
312 	RB_TREE_FOREACH_SAFE(rt, rts, rtn) {
313 		if (af != AF_UNSPEC &&
314 		    rt->rt_dest.sa_family != af &&
315 		    rt->rt_gateway.sa_family != af)
316 			continue;
317 		rb_tree_remove_node(rts, rt);
318 		rt_free(rt);
319 	}
320 }
321 
322 void
323 rt_headclear(rb_tree_t *rts, int af)
324 {
325 	struct rt *rt;
326 
327 	if (rts == NULL || (rt = RB_TREE_MIN(rts)) == NULL)
328 		return;
329 	rt_headclear0(rt->rt_ifp->ctx, rts, af);
330 }
331 
332 static void
333 rt_headfree(rb_tree_t *rts)
334 {
335 	struct rt *rt;
336 
337 	while ((rt = RB_TREE_MIN(rts)) != NULL) {
338 		rb_tree_remove_node(rts, rt);
339 		free(rt);
340 	}
341 }
342 
343 void
344 rt_dispose(struct dhcpcd_ctx *ctx)
345 {
346 
347 	assert(ctx != NULL);
348 	rt_headfree(&ctx->routes);
349 #ifdef RT_FREE_ROUTE_TABLE
350 	rt_headfree(&ctx->froutes);
351 #ifdef RT_FREE_ROUTE_TABLE_STATS
352 	logdebugx("free route list used %zu times", froutes);
353 	logdebugx("new routes from route free list %zu", nroutes);
354 	logdebugx("maximum route free list size %zu", mroutes);
355 #endif
356 #endif
357 }
358 
359 struct rt *
360 rt_new0(struct dhcpcd_ctx *ctx)
361 {
362 	struct rt *rt;
363 
364 	assert(ctx != NULL);
365 #ifdef RT_FREE_ROUTE_TABLE
366 	if ((rt = RB_TREE_MIN(&ctx->froutes)) != NULL) {
367 		rb_tree_remove_node(&ctx->froutes, rt);
368 #ifdef RT_FREE_ROUTE_TABLE_STATS
369 		croutes--;
370 		nroutes++;
371 #endif
372 	} else
373 #endif
374 	if ((rt = malloc(sizeof(*rt))) == NULL) {
375 		logerr(__func__);
376 		return NULL;
377 	}
378 	memset(rt, 0, sizeof(*rt));
379 	return rt;
380 }
381 
382 void
383 rt_setif(struct rt *rt, struct interface *ifp)
384 {
385 
386 	assert(rt != NULL);
387 	assert(ifp != NULL);
388 	rt->rt_ifp = ifp;
389 #ifdef HAVE_ROUTE_METRIC
390 	rt->rt_metric = ifp->metric;
391 	if (if_roaming(ifp))
392 		rt->rt_metric += RTMETRIC_ROAM;
393 #endif
394 }
395 
396 struct rt *
397 rt_new(struct interface *ifp)
398 {
399 	struct rt *rt;
400 
401 	assert(ifp != NULL);
402 	if ((rt = rt_new0(ifp->ctx)) == NULL)
403 		return NULL;
404 	rt_setif(rt, ifp);
405 	return rt;
406 }
407 
408 struct rt *
409 rt_proto_add_ctx(rb_tree_t *tree, struct rt *rt, struct dhcpcd_ctx *ctx)
410 {
411 
412 	rt->rt_order = ctx->rt_order++;
413 	if (rb_tree_insert_node(tree, rt) == rt)
414 		return rt;
415 
416 	rt_free(rt);
417 	errno = EEXIST;
418 	return NULL;
419 }
420 
421 struct rt *
422 rt_proto_add(rb_tree_t *tree, struct rt *rt)
423 {
424 
425 	assert (rt->rt_ifp != NULL);
426 	return rt_proto_add_ctx(tree, rt, rt->rt_ifp->ctx);
427 }
428 
429 void
430 rt_free(struct rt *rt)
431 {
432 #ifdef RT_FREE_ROUTE_TABLE
433 	struct dhcpcd_ctx *ctx;
434 
435 	assert(rt != NULL);
436 	if (rt->rt_ifp == NULL) {
437 		free(rt);
438 		return;
439 	}
440 
441 	ctx = rt->rt_ifp->ctx;
442 	rb_tree_insert_node(&ctx->froutes, rt);
443 #ifdef RT_FREE_ROUTE_TABLE_STATS
444 	croutes++;
445 	froutes++;
446 	if (croutes > mroutes)
447 		mroutes = croutes;
448 #endif
449 #else
450 	free(rt);
451 #endif
452 }
453 
454 void
455 rt_freeif(struct interface *ifp)
456 {
457 	struct dhcpcd_ctx *ctx;
458 	struct rt *rt, *rtn;
459 
460 	if (ifp == NULL)
461 		return;
462 	ctx = ifp->ctx;
463 	RB_TREE_FOREACH_SAFE(rt, &ctx->routes, rtn) {
464 		if (rt->rt_ifp == ifp) {
465 			rb_tree_remove_node(&ctx->routes, rt);
466 			rt_free(rt);
467 		}
468 	}
469 }
470 
471 /* If something other than dhcpcd removes a route,
472  * we need to remove it from our internal table. */
473 void
474 rt_recvrt(int cmd, const struct rt *rt, pid_t pid)
475 {
476 	struct dhcpcd_ctx *ctx;
477 	struct rt *f;
478 
479 	assert(rt != NULL);
480 	assert(rt->rt_ifp != NULL);
481 	assert(rt->rt_ifp->ctx != NULL);
482 
483 	ctx = rt->rt_ifp->ctx;
484 
485 	switch(cmd) {
486 	case RTM_DELETE:
487 		f = rb_tree_find_node(&ctx->routes, rt);
488 		if (f != NULL) {
489 			char buf[32];
490 
491 			rb_tree_remove_node(&ctx->routes, f);
492 			snprintf(buf, sizeof(buf), "pid %d deleted", pid);
493 			rt_desc(buf, f);
494 			rt_free(f);
495 		}
496 		break;
497 	}
498 
499 #if defined(IPV4LL) && defined(HAVE_ROUTE_METRIC)
500 	if (rt->rt_dest.sa_family == AF_INET)
501 		ipv4ll_recvrt(cmd, rt);
502 #endif
503 }
504 
505 static bool
506 rt_add(rb_tree_t *kroutes, struct rt *nrt, struct rt *ort)
507 {
508 	struct dhcpcd_ctx *ctx;
509 	bool change, kroute, result;
510 
511 	assert(nrt != NULL);
512 	ctx = nrt->rt_ifp->ctx;
513 
514 	/*
515 	 * Don't install a gateway if not asked to.
516 	 * This option is mainly for VPN users who want their VPN to be the
517 	 * default route.
518 	 * Because VPN's generally don't care about route management
519 	 * beyond their own, a longer term solution would be to remove this
520 	 * and get the VPN to inject the default route into dhcpcd somehow.
521 	 */
522 	if (((nrt->rt_ifp->active &&
523 	    !(nrt->rt_ifp->options->options & DHCPCD_GATEWAY)) ||
524 	    (!nrt->rt_ifp->active && !(ctx->options & DHCPCD_GATEWAY))) &&
525 	    sa_is_unspecified(&nrt->rt_dest) &&
526 	    sa_is_unspecified(&nrt->rt_netmask))
527 		return false;
528 
529 	rt_desc(ort == NULL ? "adding" : "changing", nrt);
530 
531 	change = kroute = result = false;
532 	if (ort == NULL) {
533 		ort = rb_tree_find_node(kroutes, nrt);
534 		if (ort != NULL &&
535 		    ((ort->rt_flags & RTF_REJECT &&
536 		      nrt->rt_flags & RTF_REJECT) ||
537 		     (ort->rt_ifp == nrt->rt_ifp &&
538 #ifdef HAVE_ROUTE_METRIC
539 		    ort->rt_metric == nrt->rt_metric &&
540 #endif
541 		    sa_cmp(&ort->rt_gateway, &nrt->rt_gateway) == 0)))
542 		{
543 			if (ort->rt_mtu == nrt->rt_mtu)
544 				return true;
545 			change = true;
546 			kroute = true;
547 		}
548 	} else if (ort->rt_dflags & RTDF_FAKE &&
549 	    !(nrt->rt_dflags & RTDF_FAKE) &&
550 	    ort->rt_ifp == nrt->rt_ifp &&
551 #ifdef HAVE_ROUTE_METRIC
552 	    ort->rt_metric == nrt->rt_metric &&
553 #endif
554 	    sa_cmp(&ort->rt_dest, &nrt->rt_dest) == 0 &&
555 	    rt_cmp_netmask(ort, nrt) == 0 &&
556 	    sa_cmp(&ort->rt_gateway, &nrt->rt_gateway) == 0)
557 	{
558 		if (ort->rt_mtu == nrt->rt_mtu)
559 			return true;
560 		change = true;
561 	}
562 
563 #ifdef RTF_CLONING
564 	/* BSD can set routes to be cloning routes.
565 	 * Cloned routes inherit the parent flags.
566 	 * As such, we need to delete and re-add the route to flush children
567 	 * to correct the flags. */
568 	if (change && ort != NULL && ort->rt_flags & RTF_CLONING)
569 		change = false;
570 #endif
571 
572 	if (change) {
573 		if (if_route(RTM_CHANGE, nrt) != -1) {
574 			result = true;
575 			goto out;
576 		}
577 		if (errno != ESRCH)
578 			logerr("if_route (CHG)");
579 	}
580 
581 #ifdef HAVE_ROUTE_METRIC
582 	/* With route metrics, we can safely add the new route before
583 	 * deleting the old route. */
584 	if (if_route(RTM_ADD, nrt) != -1) {
585 		if (ort != NULL) {
586 			if (if_route(RTM_DELETE, ort) == -1 && errno != ESRCH)
587 				logerr("if_route (DEL)");
588 		}
589 		result = true;
590 		goto out;
591 	}
592 
593 	/* If the kernel claims the route exists we need to rip out the
594 	 * old one first. */
595 	if (errno != EEXIST || ort == NULL)
596 		goto logerr;
597 #endif
598 
599 	/* No route metrics, we need to delete the old route before
600 	 * adding the new one. */
601 #ifdef ROUTE_PER_GATEWAY
602 	errno = 0;
603 #endif
604 	if (ort != NULL) {
605 		if (if_route(RTM_DELETE, ort) == -1 && errno != ESRCH)
606 			logerr("if_route (DEL)");
607 		else
608 			kroute = false;
609 	}
610 #ifdef ROUTE_PER_GATEWAY
611 	/* The OS allows many routes to the same dest with different gateways.
612 	 * dhcpcd does not support this yet, so for the time being just keep on
613 	 * deleting the route until there is an error. */
614 	if (ort != NULL && errno == 0) {
615 		for (;;) {
616 			if (if_route(RTM_DELETE, ort) == -1)
617 				break;
618 		}
619 	}
620 #endif
621 
622 	/* Shouldn't need to check for EEXIST, but some kernels don't
623 	 * dump the subnet route just after we added the address. */
624 	if (if_route(RTM_ADD, nrt) != -1 || errno == EEXIST) {
625 		result = true;
626 		goto out;
627 	}
628 
629 #ifdef HAVE_ROUTE_METRIC
630 logerr:
631 #endif
632 	logerr("if_route (ADD)");
633 
634 out:
635 	if (kroute) {
636 		rb_tree_remove_node(kroutes, ort);
637 		rt_free(ort);
638 	}
639 	return result;
640 }
641 
642 static bool
643 rt_delete(struct rt *rt)
644 {
645 	int retval;
646 
647 	rt_desc("deleting", rt);
648 	retval = if_route(RTM_DELETE, rt) == -1 ? false : true;
649 	if (!retval && errno != ENOENT && errno != ESRCH)
650 		logerr(__func__);
651 	return retval;
652 }
653 
654 static bool
655 rt_cmp(const struct rt *r1, const struct rt *r2)
656 {
657 
658 	return (r1->rt_ifp == r2->rt_ifp &&
659 #ifdef HAVE_ROUTE_METRIC
660 	    r1->rt_metric == r2->rt_metric &&
661 #endif
662 	    sa_cmp(&r1->rt_gateway, &r2->rt_gateway) == 0);
663 }
664 
665 static bool
666 rt_doroute(rb_tree_t *kroutes, struct rt *rt)
667 {
668 	struct dhcpcd_ctx *ctx;
669 	struct rt *or;
670 
671 	ctx = rt->rt_ifp->ctx;
672 	/* Do we already manage it? */
673 	or = rb_tree_find_node(&ctx->routes, rt);
674 	if (or != NULL) {
675 		if (rt->rt_dflags & RTDF_FAKE)
676 			return true;
677 		if (or->rt_dflags & RTDF_FAKE ||
678 		    !rt_cmp(rt, or) ||
679 		    (rt->rt_ifa.sa_family != AF_UNSPEC &&
680 		    sa_cmp(&or->rt_ifa, &rt->rt_ifa) != 0) ||
681 		    or->rt_mtu != rt->rt_mtu)
682 		{
683 			if (!rt_add(kroutes, rt, or))
684 				return false;
685 		}
686 		rb_tree_remove_node(&ctx->routes, or);
687 		rt_free(or);
688 	} else {
689 		if (rt->rt_dflags & RTDF_FAKE) {
690 			or = rb_tree_find_node(kroutes, rt);
691 			if (or == NULL)
692 				return false;
693 			if (!rt_cmp(rt, or))
694 				return false;
695 		} else {
696 			if (!rt_add(kroutes, rt, NULL))
697 				return false;
698 		}
699 	}
700 
701 	return true;
702 }
703 
704 void
705 rt_build(struct dhcpcd_ctx *ctx, int af)
706 {
707 	rb_tree_t routes, added, kroutes;
708 	struct rt *rt, *rtn;
709 	unsigned long long o;
710 
711 	rb_tree_init(&routes, &rt_compare_proto_ops);
712 	rb_tree_init(&added, &rt_compare_os_ops);
713 	rb_tree_init(&kroutes, &rt_compare_os_ops);
714 	if (if_initrt(ctx, &kroutes, af) != 0)
715 		logerr("%s: if_initrt", __func__);
716 	ctx->rt_order = 0;
717 	ctx->options |= DHCPCD_RTBUILD;
718 
719 #ifdef INET
720 	if (!inet_getroutes(ctx, &routes))
721 		goto getfail;
722 #endif
723 #ifdef INET6
724 	if (!inet6_getroutes(ctx, &routes))
725 		goto getfail;
726 #endif
727 
728 #ifdef BSD
729 	/* Rewind the miss filter */
730 	ctx->rt_missfilterlen = 0;
731 #endif
732 
733 	RB_TREE_FOREACH_SAFE(rt, &routes, rtn) {
734 		if (rt->rt_ifp->active) {
735 			if (!(rt->rt_ifp->options->options & DHCPCD_CONFIGURE))
736 				continue;
737 		} else if (!(ctx->options & DHCPCD_CONFIGURE))
738 			continue;
739 #ifdef BSD
740 		if (rt_is_default(rt) &&
741 		    if_missfilter(rt->rt_ifp, &rt->rt_gateway) == -1)
742 			logerr("if_missfilter");
743 #endif
744 		if ((rt->rt_dest.sa_family != af &&
745 		    rt->rt_dest.sa_family != AF_UNSPEC) ||
746 		    (rt->rt_gateway.sa_family != af &&
747 		    rt->rt_gateway.sa_family != AF_UNSPEC))
748 			continue;
749 		/* Is this route already in our table? */
750 		if (rb_tree_find_node(&added, rt) != NULL)
751 			continue;
752 		if (rt_doroute(&kroutes, rt)) {
753 			rb_tree_remove_node(&routes, rt);
754 			if (rb_tree_insert_node(&added, rt) != rt) {
755 				errno = EEXIST;
756 				logerr(__func__);
757 				rt_free(rt);
758 			}
759 		}
760 	}
761 
762 #ifdef BSD
763 	if (if_missfilter_apply(ctx) == -1 && errno != ENOTSUP)
764 		logerr("if_missfilter_apply");
765 #endif
766 
767 	/* Remove old routes we used to manage. */
768 	RB_TREE_FOREACH_REVERSE_SAFE(rt, &ctx->routes, rtn) {
769 		if ((rt->rt_dest.sa_family != af &&
770 		    rt->rt_dest.sa_family != AF_UNSPEC) ||
771 		    (rt->rt_gateway.sa_family != af &&
772 		    rt->rt_gateway.sa_family != AF_UNSPEC))
773 			continue;
774 		rb_tree_remove_node(&ctx->routes, rt);
775 		if (rb_tree_find_node(&added, rt) == NULL) {
776 			o = rt->rt_ifp->options ?
777 			    rt->rt_ifp->options->options :
778 			    ctx->options;
779 			if ((o &
780 				(DHCPCD_EXITING | DHCPCD_PERSISTENT)) !=
781 				(DHCPCD_EXITING | DHCPCD_PERSISTENT))
782 				rt_delete(rt);
783 		}
784 		rt_free(rt);
785 	}
786 
787 	/* XXX This needs to be optimised. */
788 	while ((rt = RB_TREE_MIN(&added)) != NULL) {
789 		rb_tree_remove_node(&added, rt);
790 		if (rb_tree_insert_node(&ctx->routes, rt) != rt) {
791 			errno = EEXIST;
792 			logerr(__func__);
793 			rt_free(rt);
794 		}
795 	}
796 
797 getfail:
798 	rt_headclear(&routes, AF_UNSPEC);
799 	rt_headclear(&kroutes, AF_UNSPEC);
800 }
801