xref: /freebsd/contrib/bsnmp/snmp_mibII/mibII.c (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /*
2  * Copyright (c) 2001-2003
3  *	Fraunhofer Institute for Open Communication Systems (FhG Fokus).
4  *	All rights reserved.
5  *
6  * Author: Harti Brandt <harti@freebsd.org>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY AUTHOR 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 AUTHOR 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
27  * SUCH DAMAGE.
28  *
29  * $Begemot: bsnmp/snmp_mibII/mibII.c,v 1.24 2006/02/14 09:04:18 brandt_h Exp $
30  *
31  * Implementation of the standard interfaces and ip MIB.
32  */
33 #include "mibII.h"
34 #include "mibII_oid.h"
35 #include <net/if_types.h>
36 
37 
38 /*****************************/
39 
40 /* our module */
41 static struct lmodule *module;
42 
43 /* routing socket */
44 static int route;
45 static void *route_fd;
46 
47 /* if-index allocator */
48 static uint32_t next_if_index = 1;
49 
50 /* re-fetch arp table */
51 static int update_arp;
52 static int in_update_arp;
53 
54 /* OR registrations */
55 static u_int ifmib_reg;
56 static u_int ipmib_reg;
57 static u_int tcpmib_reg;
58 static u_int udpmib_reg;
59 static u_int ipForward_reg;
60 
61 /*****************************/
62 
63 /* list of all IP addresses */
64 struct mibifa_list mibifa_list = TAILQ_HEAD_INITIALIZER(mibifa_list);
65 
66 /* list of all interfaces */
67 struct mibif_list mibif_list = TAILQ_HEAD_INITIALIZER(mibif_list);
68 
69 /* list of dynamic interface names */
70 struct mibdynif_list mibdynif_list = SLIST_HEAD_INITIALIZER(mibdynif_list);
71 
72 /* list of all interface index mappings */
73 struct mibindexmap_list mibindexmap_list = STAILQ_HEAD_INITIALIZER(mibindexmap_list);
74 
75 /* list of all stacking entries */
76 struct mibifstack_list mibifstack_list = TAILQ_HEAD_INITIALIZER(mibifstack_list);
77 
78 /* list of all receive addresses */
79 struct mibrcvaddr_list mibrcvaddr_list = TAILQ_HEAD_INITIALIZER(mibrcvaddr_list);
80 
81 /* list of all NetToMedia entries */
82 struct mibarp_list mibarp_list = TAILQ_HEAD_INITIALIZER(mibarp_list);
83 
84 /* number of interfaces */
85 int32_t mib_if_number;
86 
87 /* last change of table */
88 uint64_t mib_iftable_last_change;
89 
90 /* last change of stack table */
91 uint64_t mib_ifstack_last_change;
92 
93 /* if this is set, one of our lists may be bad. refresh them when idle */
94 int mib_iflist_bad;
95 
96 /* network socket */
97 int mib_netsock;
98 
99 /* last time refreshed */
100 uint64_t mibarpticks;
101 
102 /* info on system clocks */
103 struct clockinfo clockinfo;
104 
105 /* list of all New if registrations */
106 static struct newifreg_list newifreg_list = TAILQ_HEAD_INITIALIZER(newifreg_list);
107 
108 /* baud rate of fastest interface */
109 uint64_t mibif_maxspeed;
110 
111 /* user-forced update interval */
112 u_int mibif_force_hc_update_interval;
113 
114 /* current update interval */
115 u_int mibif_hc_update_interval;
116 
117 /* HC update timer handle */
118 static void *hc_update_timer;
119 
120 /*****************************/
121 
122 static const struct asn_oid oid_ifMIB = OIDX_ifMIB;
123 static const struct asn_oid oid_ipMIB = OIDX_ipMIB;
124 static const struct asn_oid oid_tcpMIB = OIDX_tcpMIB;
125 static const struct asn_oid oid_udpMIB = OIDX_udpMIB;
126 static const struct asn_oid oid_ipForward = OIDX_ipForward;
127 static const struct asn_oid oid_linkDown = OIDX_linkDown;
128 static const struct asn_oid oid_linkUp = OIDX_linkUp;
129 static const struct asn_oid oid_ifIndex = OIDX_ifIndex;
130 
131 /*****************************/
132 
133 /*
134  * Find an interface
135  */
136 struct mibif *
137 mib_find_if(u_int idx)
138 {
139 	struct mibif *ifp;
140 
141 	TAILQ_FOREACH(ifp, &mibif_list, link)
142 		if (ifp->index == idx)
143 			return (ifp);
144 	return (NULL);
145 }
146 
147 struct mibif *
148 mib_find_if_sys(u_int sysindex)
149 {
150 	struct mibif *ifp;
151 
152 	TAILQ_FOREACH(ifp, &mibif_list, link)
153 		if (ifp->sysindex == sysindex)
154 			return (ifp);
155 	return (NULL);
156 }
157 
158 struct mibif *
159 mib_find_if_name(const char *name)
160 {
161 	struct mibif *ifp;
162 
163 	TAILQ_FOREACH(ifp, &mibif_list, link)
164 		if (strcmp(ifp->name, name) == 0)
165 			return (ifp);
166 	return (NULL);
167 }
168 
169 /*
170  * Check whether an interface is dynamic. The argument may include the
171  * unit number. This assumes, that the name part does NOT contain digits.
172  */
173 int
174 mib_if_is_dyn(const char *name)
175 {
176 	size_t len;
177 	struct mibdynif *d;
178 
179 	for (len = 0; name[len] != '\0' && isalpha(name[len]) ; len++)
180 		;
181 	SLIST_FOREACH(d, &mibdynif_list, link)
182 		if (strlen(d->name) == len && strncmp(d->name, name, len) == 0)
183 			return (1);
184 	return (0);
185 }
186 
187 /* set an interface name to dynamic mode */
188 void
189 mib_if_set_dyn(const char *name)
190 {
191 	struct mibdynif *d;
192 
193 	SLIST_FOREACH(d, &mibdynif_list, link)
194 		if (strcmp(name, d->name) == 0)
195 			return;
196 	if ((d = malloc(sizeof(*d))) == NULL)
197 		err(1, NULL);
198 	strcpy(d->name, name);
199 	SLIST_INSERT_HEAD(&mibdynif_list, d, link);
200 }
201 
202 /*
203  * register for interface creations
204  */
205 int
206 mib_register_newif(int (*func)(struct mibif *), const struct lmodule *mod)
207 {
208 	struct newifreg *reg;
209 
210 	TAILQ_FOREACH(reg, &newifreg_list, link)
211 		if (reg->mod == mod) {
212 			reg->func = func;
213 			return (0);
214 		}
215 	if ((reg = malloc(sizeof(*reg))) == NULL) {
216 		syslog(LOG_ERR, "newifreg: %m");
217 		return (-1);
218 	}
219 	reg->mod = mod;
220 	reg->func = func;
221 	TAILQ_INSERT_TAIL(&newifreg_list, reg, link);
222 
223 	return (0);
224 }
225 
226 void
227 mib_unregister_newif(const struct lmodule *mod)
228 {
229 	struct newifreg *reg;
230 
231 	TAILQ_FOREACH(reg, &newifreg_list, link)
232 		if (reg->mod == mod) {
233 			TAILQ_REMOVE(&newifreg_list, reg, link);
234 			free(reg);
235 			return;
236 		}
237 
238 }
239 
240 struct mibif *
241 mib_first_if(void)
242 {
243 	return (TAILQ_FIRST(&mibif_list));
244 }
245 struct mibif *
246 mib_next_if(const struct mibif *ifp)
247 {
248 	return (TAILQ_NEXT(ifp, link));
249 }
250 
251 /*
252  * Change the admin status of an interface
253  */
254 int
255 mib_if_admin(struct mibif *ifp, int up)
256 {
257 	struct ifreq ifr;
258 
259 	strncpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
260 	if (ioctl(mib_netsock, SIOCGIFFLAGS, &ifr) == -1) {
261 		syslog(LOG_ERR, "SIOCGIFFLAGS(%s): %m", ifp->name);
262 		return (-1);
263 	}
264 	if (up)
265 		ifr.ifr_flags |= IFF_UP;
266 	else
267 		ifr.ifr_flags &= ~IFF_UP;
268 	if (ioctl(mib_netsock, SIOCSIFFLAGS, &ifr) == -1) {
269 		syslog(LOG_ERR, "SIOCSIFFLAGS(%s): %m", ifp->name);
270 		return (-1);
271 	}
272 
273 	(void)mib_fetch_ifmib(ifp);
274 
275 	return (0);
276 }
277 
278 /*
279  * Generate a link up/down trap
280  */
281 static void
282 link_trap(struct mibif *ifp, int up)
283 {
284 	struct snmp_value ifindex;
285 
286 	ifindex.var = oid_ifIndex;
287 	ifindex.var.subs[ifindex.var.len++] = ifp->index;
288 	ifindex.syntax = SNMP_SYNTAX_INTEGER;
289 	ifindex.v.integer = ifp->index;
290 
291 	snmp_send_trap(up ? &oid_linkUp : &oid_linkDown, &ifindex,
292 	    (struct snmp_value *)NULL);
293 }
294 
295 /**
296  * Fetch the GENERIC IFMIB and update the HC counters
297  */
298 static int
299 fetch_generic_mib(struct mibif *ifp, const struct ifmibdata *old)
300 {
301 	int name[6];
302 	size_t len;
303 	struct mibif_private *p = ifp->private;
304 
305 	name[0] = CTL_NET;
306 	name[1] = PF_LINK;
307 	name[2] = NETLINK_GENERIC;
308 	name[3] = IFMIB_IFDATA;
309 	name[4] = ifp->sysindex;
310 	name[5] = IFDATA_GENERAL;
311 
312 	len = sizeof(ifp->mib);
313 	if (sysctl(name, 6, &ifp->mib, &len, NULL, 0) == -1) {
314 		if (errno != ENOENT)
315 			syslog(LOG_WARNING, "sysctl(ifmib, %s) failed %m",
316 			    ifp->name);
317 		return (-1);
318 	}
319 
320 	/*
321 	 * Assume that one of the two following compounds is optimized away
322 	 */
323 	if (ULONG_MAX >= 0xffffffffffffffffULL) {
324 		p->hc_inoctets = ifp->mib.ifmd_data.ifi_ibytes;
325 		p->hc_outoctets = ifp->mib.ifmd_data.ifi_obytes;
326 		p->hc_omcasts = ifp->mib.ifmd_data.ifi_omcasts;
327 		p->hc_opackets = ifp->mib.ifmd_data.ifi_opackets;
328 		p->hc_imcasts = ifp->mib.ifmd_data.ifi_imcasts;
329 		p->hc_ipackets = ifp->mib.ifmd_data.ifi_ipackets;
330 
331 	} else if (ULONG_MAX >= 0xffffffff) {
332 
333 #define	UPDATE(HC, MIB)							\
334 		if (old->ifmd_data.MIB > ifp->mib.ifmd_data.MIB)	\
335 			p->HC += (0x100000000ULL +			\
336 			    ifp->mib.ifmd_data.MIB) -			\
337 			    old->ifmd_data.MIB;				\
338 		else							\
339 			p->HC += ifp->mib.ifmd_data.MIB -		\
340 			    old->ifmd_data.MIB;
341 
342 		UPDATE(hc_inoctets, ifi_ibytes)
343 		UPDATE(hc_outoctets, ifi_obytes)
344 		UPDATE(hc_omcasts, ifi_omcasts)
345 		UPDATE(hc_opackets, ifi_opackets)
346 		UPDATE(hc_imcasts, ifi_imcasts)
347 		UPDATE(hc_ipackets, ifi_ipackets)
348 
349 #undef	UPDATE
350 	} else
351 		abort();
352 	return (0);
353 }
354 
355 /**
356  * Update the 64-bit interface counters
357  */
358 static void
359 update_hc_counters(void *arg __unused)
360 {
361 	struct mibif *ifp;
362 	struct ifmibdata oldmib;
363 
364 	TAILQ_FOREACH(ifp, &mibif_list, link) {
365 		oldmib = ifp->mib;
366 		(void)fetch_generic_mib(ifp, &oldmib);
367 	}
368 }
369 
370 /**
371  * Recompute the poll timer for the HC counters
372  */
373 void
374 mibif_reset_hc_timer(void)
375 {
376 	u_int ticks;
377 
378 	if ((ticks = mibif_force_hc_update_interval) == 0) {
379 		if (mibif_maxspeed <= 10000000) {
380 			/* at 10Mbps overflow needs 3436 seconds */
381 			ticks = 3000 * 100;	/* 50 minutes */
382 		} else if (mibif_maxspeed <= 100000000) {
383 			/* at 100Mbps overflow needs 343 seconds */
384 			ticks = 300 * 100;	/* 5 minutes */
385 		} else if (mibif_maxspeed < 650000000) {
386 			/* at 622Mbps overflow needs 53 seconds */
387 			ticks = 40 * 100;	/* 40 seconds */
388 		} else if (mibif_maxspeed <= 1000000000) {
389 			/* at 1Gbps overflow needs  34 seconds */
390 			ticks = 20 * 100;	/* 20 seconds */
391 		} else {
392 			/* at 10Gbps overflow needs 3.4 seconds */
393 			ticks = 100;		/* 1 seconds */
394 		}
395 	}
396 
397 	if (ticks == mibif_hc_update_interval)
398 		return;
399 
400 	if (hc_update_timer != NULL) {
401 		timer_stop(hc_update_timer);
402 		hc_update_timer = NULL;
403 	}
404 	update_hc_counters(NULL);
405 	if ((hc_update_timer = timer_start_repeat(ticks * 10, ticks * 10,
406 	    update_hc_counters, NULL, module)) == NULL) {
407 		syslog(LOG_ERR, "timer_start(%u): %m", ticks);
408 		return;
409 	}
410 	mibif_hc_update_interval = ticks;
411 }
412 
413 /*
414  * Fetch new MIB data.
415  */
416 int
417 mib_fetch_ifmib(struct mibif *ifp)
418 {
419 	int name[6];
420 	size_t len;
421 	void *newmib;
422 	struct ifmibdata oldmib = ifp->mib;
423 
424 	if (fetch_generic_mib(ifp, &oldmib) == -1)
425 		return (-1);
426 
427 	/*
428 	 * Quoting RFC2863, 3.1.15: "... LinkUp and linkDown traps are
429 	 * generated just after ifOperStatus leaves, or just before it
430 	 * enters, the down state, respectively;"
431 	 */
432 	if (ifp->trap_enable && ifp->mib.ifmd_data.ifi_link_state !=
433 	    oldmib.ifmd_data.ifi_link_state &&
434 	    (ifp->mib.ifmd_data.ifi_link_state == LINK_STATE_DOWN ||
435 	    oldmib.ifmd_data.ifi_link_state == LINK_STATE_DOWN))
436 		link_trap(ifp, ifp->mib.ifmd_data.ifi_link_state ==
437 		    LINK_STATE_UP ? 1 : 0);
438 
439 	ifp->flags &= ~(MIBIF_HIGHSPEED | MIBIF_VERYHIGHSPEED);
440 	if (ifp->mib.ifmd_data.ifi_baudrate > 20000000) {
441 		ifp->flags |= MIBIF_HIGHSPEED;
442 		if (ifp->mib.ifmd_data.ifi_baudrate > 650000000)
443 			ifp->flags |= MIBIF_VERYHIGHSPEED;
444 	}
445 	if (ifp->mib.ifmd_data.ifi_baudrate > mibif_maxspeed) {
446 		mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
447 		mibif_reset_hc_timer();
448 	}
449 
450 	/*
451 	 * linkspecific MIB
452 	 */
453 	name[0] = CTL_NET;
454 	name[1] = PF_LINK;
455 	name[2] = NETLINK_GENERIC;
456 	name[3] = IFMIB_IFDATA;
457 	name[4] = ifp->sysindex;
458 	name[5] = IFDATA_LINKSPECIFIC;
459 	if (sysctl(name, 6, NULL, &len, NULL, 0) == -1) {
460 		syslog(LOG_WARNING, "sysctl linkmib estimate (%s): %m",
461 		    ifp->name);
462 		if (ifp->specmib != NULL) {
463 			ifp->specmib = NULL;
464 			ifp->specmiblen = 0;
465 		}
466 		goto out;
467 	}
468 	if (len == 0) {
469 		if (ifp->specmib != NULL) {
470 			ifp->specmib = NULL;
471 			ifp->specmiblen = 0;
472 		}
473 		goto out;
474 	}
475 
476 	if (ifp->specmiblen != len) {
477 		if ((newmib = realloc(ifp->specmib, len)) == NULL) {
478 			ifp->specmib = NULL;
479 			ifp->specmiblen = 0;
480 			goto out;
481 		}
482 		ifp->specmib = newmib;
483 		ifp->specmiblen = len;
484 	}
485 	if (sysctl(name, 6, ifp->specmib, &len, NULL, 0) == -1) {
486 		syslog(LOG_WARNING, "sysctl linkmib (%s): %m", ifp->name);
487 		if (ifp->specmib != NULL) {
488 			ifp->specmib = NULL;
489 			ifp->specmiblen = 0;
490 		}
491 	}
492 
493   out:
494 	ifp->mibtick = get_ticks();
495 	return (0);
496 }
497 
498 /* find first/next address for a given interface */
499 struct mibifa *
500 mib_first_ififa(const struct mibif *ifp)
501 {
502 	struct mibifa *ifa;
503 
504 	TAILQ_FOREACH(ifa, &mibifa_list, link)
505 		if (ifp->index == ifa->ifindex)
506 			return (ifa);
507 	return (NULL);
508 }
509 
510 struct mibifa *
511 mib_next_ififa(struct mibifa *ifa0)
512 {
513 	struct mibifa *ifa;
514 
515 	ifa = ifa0;
516 	while ((ifa = TAILQ_NEXT(ifa, link)) != NULL)
517 		if (ifa->ifindex == ifa0->ifindex)
518 			return (ifa);
519 	return (NULL);
520 }
521 
522 /*
523  * Allocate a new IFA
524  */
525 static struct mibifa *
526 alloc_ifa(u_int ifindex, struct in_addr addr)
527 {
528 	struct mibifa *ifa;
529 	uint32_t ha;
530 
531 	if ((ifa = malloc(sizeof(struct mibifa))) == NULL) {
532 		syslog(LOG_ERR, "ifa: %m");
533 		return (NULL);
534 	}
535 	ifa->inaddr = addr;
536 	ifa->ifindex = ifindex;
537 
538 	ha = ntohl(ifa->inaddr.s_addr);
539 	ifa->index.len = 4;
540 	ifa->index.subs[0] = (ha >> 24) & 0xff;
541 	ifa->index.subs[1] = (ha >> 16) & 0xff;
542 	ifa->index.subs[2] = (ha >>  8) & 0xff;
543 	ifa->index.subs[3] = (ha >>  0) & 0xff;
544 
545 	ifa->flags = 0;
546 	ifa->inbcast.s_addr = 0;
547 	ifa->inmask.s_addr = 0xffffffff;
548 
549 	INSERT_OBJECT_OID(ifa, &mibifa_list);
550 
551 	return (ifa);
552 }
553 
554 /*
555  * Delete an interface address
556  */
557 static void
558 destroy_ifa(struct mibifa *ifa)
559 {
560 	TAILQ_REMOVE(&mibifa_list, ifa, link);
561 	free(ifa);
562 }
563 
564 
565 /*
566  * Helper routine to extract the sockaddr structures from a routing
567  * socket message.
568  */
569 void
570 mib_extract_addrs(int addrs, u_char *info, struct sockaddr **out)
571 {
572 	u_int i;
573 
574 	for (i = 0; i < RTAX_MAX; i++) {
575 		if ((addrs & (1 << i)) != 0) {
576 			*out = (struct sockaddr *)(void *)info;
577 			info += roundup((*out)->sa_len, sizeof(long));
578 		} else
579 			*out = NULL;
580 		out++;
581 	}
582 }
583 
584 /*
585  * save the phys address of an interface. Handle receive address entries here.
586  */
587 static void
588 get_physaddr(struct mibif *ifp, struct sockaddr_dl *sdl, u_char *ptr)
589 {
590 	u_char *np;
591 	struct mibrcvaddr *rcv;
592 
593 	if (sdl->sdl_alen == 0) {
594 		/* no address */
595 		if (ifp->physaddrlen != 0) {
596 			if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
597 			    ifp->physaddrlen)) != NULL)
598 				mib_rcvaddr_delete(rcv);
599 			free(ifp->physaddr);
600 			ifp->physaddr = NULL;
601 			ifp->physaddrlen = 0;
602 		}
603 		return;
604 	}
605 
606 	if (ifp->physaddrlen != sdl->sdl_alen) {
607 		/* length changed */
608 		if (ifp->physaddrlen) {
609 			/* delete olf receive address */
610 			if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
611 			    ifp->physaddrlen)) != NULL)
612 				mib_rcvaddr_delete(rcv);
613 		}
614 		if ((np = realloc(ifp->physaddr, sdl->sdl_alen)) == NULL) {
615 			free(ifp->physaddr);
616 			ifp->physaddr = NULL;
617 			ifp->physaddrlen = 0;
618 			return;
619 		}
620 		ifp->physaddr = np;
621 		ifp->physaddrlen = sdl->sdl_alen;
622 
623 	} else if (memcmp(ifp->physaddr, ptr, ifp->physaddrlen) == 0) {
624 		/* no change */
625 		return;
626 
627 	} else {
628 		/* address changed */
629 
630 		/* delete olf receive address */
631 		if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
632 		    ifp->physaddrlen)) != NULL)
633 			mib_rcvaddr_delete(rcv);
634 	}
635 
636 	memcpy(ifp->physaddr, ptr, ifp->physaddrlen);
637 
638 	/* make new receive address */
639 	if ((rcv = mib_rcvaddr_create(ifp, ifp->physaddr, ifp->physaddrlen)) != NULL)
640 		rcv->flags |= MIBRCVADDR_HW;
641 }
642 
643 /*
644  * Free an interface
645  */
646 static void
647 mibif_free(struct mibif *ifp)
648 {
649 	struct mibif *ifp1;
650 	struct mibindexmap *map;
651 	struct mibifa *ifa, *ifa1;
652 	struct mibrcvaddr *rcv, *rcv1;
653 	struct mibarp *at, *at1;
654 
655 	if (ifp->xnotify != NULL)
656 		(*ifp->xnotify)(ifp, MIBIF_NOTIFY_DESTROY, ifp->xnotify_data);
657 
658 	(void)mib_ifstack_delete(ifp, NULL);
659 	(void)mib_ifstack_delete(NULL, ifp);
660 
661 	TAILQ_REMOVE(&mibif_list, ifp, link);
662 
663 	/* if this was the fastest interface - recompute this */
664 	if (ifp->mib.ifmd_data.ifi_baudrate == mibif_maxspeed) {
665 		mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
666 		TAILQ_FOREACH(ifp1, &mibif_list, link)
667 			if (ifp1->mib.ifmd_data.ifi_baudrate > mibif_maxspeed)
668 				mibif_maxspeed =
669 				    ifp1->mib.ifmd_data.ifi_baudrate;
670 		mibif_reset_hc_timer();
671 	}
672 
673 	free(ifp->private);
674 	if (ifp->physaddr != NULL)
675 		free(ifp->physaddr);
676 	if (ifp->specmib != NULL)
677 		free(ifp->specmib);
678 
679 	STAILQ_FOREACH(map, &mibindexmap_list, link)
680 		if (map->mibif == ifp) {
681 			map->mibif = NULL;
682 			break;
683 		}
684 
685 	/* purge interface addresses */
686 	ifa = TAILQ_FIRST(&mibifa_list);
687 	while (ifa != NULL) {
688 		ifa1 = TAILQ_NEXT(ifa, link);
689 		if (ifa->ifindex == ifp->index)
690 			destroy_ifa(ifa);
691 		ifa = ifa1;
692 	}
693 
694 	/* purge receive addresses */
695 	rcv = TAILQ_FIRST(&mibrcvaddr_list);
696 	while (rcv != NULL) {
697 		rcv1 = TAILQ_NEXT(rcv, link);
698 		if (rcv->ifindex == ifp->index)
699 			mib_rcvaddr_delete(rcv);
700 		rcv = rcv1;
701 	}
702 
703 	/* purge ARP entries */
704 	at = TAILQ_FIRST(&mibarp_list);
705 	while (at != NULL) {
706 		at1 = TAILQ_NEXT(at, link);
707 		if (at->index.subs[0] == ifp->index)
708 			mib_arp_delete(at);
709 		at = at1;
710 	}
711 
712 
713 	free(ifp);
714 	mib_if_number--;
715 	mib_iftable_last_change = this_tick;
716 }
717 
718 /*
719  * Create a new interface
720  */
721 static struct mibif *
722 mibif_create(u_int sysindex, const char *name)
723 {
724 	struct mibif *ifp;
725 	struct mibindexmap *map;
726 
727 	if ((ifp = malloc(sizeof(*ifp))) == NULL) {
728 		syslog(LOG_WARNING, "%s: %m", __func__);
729 		return (NULL);
730 	}
731 	memset(ifp, 0, sizeof(*ifp));
732 	if ((ifp->private = malloc(sizeof(struct mibif_private))) == NULL) {
733 		syslog(LOG_WARNING, "%s: %m", __func__);
734 		free(ifp);
735 		return (NULL);
736 	}
737 	memset(ifp->private, 0, sizeof(struct mibif_private));
738 
739 	ifp->sysindex = sysindex;
740 	strcpy(ifp->name, name);
741 	strcpy(ifp->descr, name);
742 	ifp->spec_oid = oid_zeroDotZero;
743 
744 	map = NULL;
745 	if (!mib_if_is_dyn(ifp->name)) {
746 		/* non-dynamic. look whether we know the interface */
747 		STAILQ_FOREACH(map, &mibindexmap_list, link)
748 			if (strcmp(map->name, ifp->name) == 0) {
749 				ifp->index = map->ifindex;
750 				map->mibif = ifp;
751 				break;
752 			}
753 		/* assume it has a connector if it is not dynamic */
754 		ifp->has_connector = 1;
755 		ifp->trap_enable = 1;
756 	}
757 	if (map == NULL) {
758 		/* new interface - get new index */
759 		if (next_if_index > 0x7fffffff)
760 			errx(1, "ifindex wrap");
761 
762 		if ((map = malloc(sizeof(*map))) == NULL) {
763 			syslog(LOG_ERR, "ifmap: %m");
764 			free(ifp);
765 			return (NULL);
766 		}
767 		map->ifindex = next_if_index++;
768 		map->sysindex = ifp->sysindex;
769 		strcpy(map->name, ifp->name);
770 		map->mibif = ifp;
771 		STAILQ_INSERT_TAIL(&mibindexmap_list, map, link);
772 	} else {
773 		/* re-instantiate. Introduce a counter discontinuity */
774 		ifp->counter_disc = get_ticks();
775 	}
776 	ifp->index = map->ifindex;
777 	ifp->mib.ifmd_data.ifi_link_state = LINK_STATE_UNKNOWN;
778 
779 	INSERT_OBJECT_INT(ifp, &mibif_list);
780 	mib_if_number++;
781 	mib_iftable_last_change = this_tick;
782 
783 	/* instantiate default ifStack entries */
784 	(void)mib_ifstack_create(ifp, NULL);
785 	(void)mib_ifstack_create(NULL, ifp);
786 
787 	return (ifp);
788 }
789 
790 /*
791  * Inform all interested parties about a new interface
792  */
793 static void
794 notify_newif(struct mibif *ifp)
795 {
796 	struct newifreg *reg;
797 
798 	TAILQ_FOREACH(reg, &newifreg_list, link)
799 		if ((*reg->func)(ifp))
800 			return;
801 }
802 
803 /*
804  * This is called for new interfaces after we have fetched the interface
805  * MIB. If this is a broadcast interface try to guess the broadcast address
806  * depending on the interface type.
807  */
808 static void
809 check_llbcast(struct mibif *ifp)
810 {
811 	static u_char ether_bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
812 	static u_char arcnet_bcast = 0;
813 	struct mibrcvaddr *rcv;
814 
815 	if (!(ifp->mib.ifmd_flags & IFF_BROADCAST))
816 		return;
817 
818 	switch (ifp->mib.ifmd_data.ifi_type) {
819 
820 	  case IFT_ETHER:
821 	  case IFT_FDDI:
822 	  case IFT_ISO88025:
823 		if (mib_find_rcvaddr(ifp->index, ether_bcast, 6) == NULL &&
824 		    (rcv = mib_rcvaddr_create(ifp, ether_bcast, 6)) != NULL)
825 			rcv->flags |= MIBRCVADDR_BCAST;
826 		break;
827 
828 	  case IFT_ARCNET:
829 		if (mib_find_rcvaddr(ifp->index, &arcnet_bcast, 1) == NULL &&
830 		    (rcv = mib_rcvaddr_create(ifp, &arcnet_bcast, 1)) != NULL)
831 			rcv->flags |= MIBRCVADDR_BCAST;
832 		break;
833 	}
834 }
835 
836 
837 /*
838  * Retrieve the current interface list from the system.
839  */
840 void
841 mib_refresh_iflist(void)
842 {
843 	struct mibif *ifp, *ifp1;
844 	size_t len;
845 	u_short idx;
846 	int name[6];
847 	int count;
848 	struct ifmibdata mib;
849 
850 	TAILQ_FOREACH(ifp, &mibif_list, link)
851 		ifp->flags &= ~MIBIF_FOUND;
852 
853 	len = sizeof(count);
854 	if (sysctlbyname("net.link.generic.system.ifcount", &count, &len,
855 	    NULL, 0) == -1) {
856 		syslog(LOG_ERR, "ifcount: %m");
857 		return;
858 	}
859 	name[0] = CTL_NET;
860 	name[1] = PF_LINK;
861 	name[2] = NETLINK_GENERIC;
862 	name[3] = IFMIB_IFDATA;
863 	name[5] = IFDATA_GENERAL;
864 	for (idx = 1; idx <= count; idx++) {
865 		name[4] = idx;
866 		len = sizeof(mib);
867 		if (sysctl(name, 6, &mib, &len, NULL, 0) == -1) {
868 			if (errno == ENOENT)
869 				continue;
870 			syslog(LOG_ERR, "ifmib(%u): %m", idx);
871 			return;
872 		}
873 		if ((ifp = mib_find_if_sys(idx)) != NULL) {
874 			ifp->flags |= MIBIF_FOUND;
875 			continue;
876 		}
877 		/* Unknown interface - create */
878 		if ((ifp = mibif_create(idx, mib.ifmd_name)) != NULL) {
879 			ifp->flags |= MIBIF_FOUND;
880 			(void)mib_fetch_ifmib(ifp);
881 			check_llbcast(ifp);
882 			notify_newif(ifp);
883 		}
884 	}
885 
886 	/*
887 	 * Purge interfaces that disappeared
888 	 */
889 	ifp = TAILQ_FIRST(&mibif_list);
890 	while (ifp != NULL) {
891 		ifp1 = TAILQ_NEXT(ifp, link);
892 		if (!(ifp->flags & MIBIF_FOUND))
893 			mibif_free(ifp);
894 		ifp = ifp1;
895 	}
896 }
897 
898 /*
899  * Find an interface address
900  */
901 struct mibifa *
902 mib_find_ifa(struct in_addr addr)
903 {
904 	struct mibifa *ifa;
905 
906 	TAILQ_FOREACH(ifa, &mibifa_list, link)
907 		if (ifa->inaddr.s_addr == addr.s_addr)
908 			return (ifa);
909 	return (NULL);
910 }
911 
912 /*
913  * Process a new ARP entry
914  */
915 static void
916 process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl,
917     const struct sockaddr_in *sa)
918 {
919 	struct mibif *ifp;
920 	struct mibarp *at;
921 
922 	/* IP arp table entry */
923 	if (sdl->sdl_alen == 0) {
924 		update_arp = 1;
925 		return;
926 	}
927 	if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL)
928 		return;
929 	/* have a valid entry */
930 	if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL &&
931 	    (at = mib_arp_create(ifp, sa->sin_addr,
932 	    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
933 		return;
934 
935 	if (rtm->rtm_rmx.rmx_expire == 0)
936 		at->flags |= MIBARP_PERM;
937 	else
938 		at->flags &= ~MIBARP_PERM;
939 	at->flags |= MIBARP_FOUND;
940 }
941 
942 /*
943  * Handle a routing socket message.
944  */
945 static void
946 handle_rtmsg(struct rt_msghdr *rtm)
947 {
948 	struct sockaddr *addrs[RTAX_MAX];
949 	struct if_msghdr *ifm;
950 	struct ifa_msghdr *ifam;
951 	struct ifma_msghdr *ifmam;
952 #ifdef RTM_IFANNOUNCE
953 	struct if_announcemsghdr *ifan;
954 #endif
955 	struct mibif *ifp;
956 	struct sockaddr_dl *sdl;
957 	struct sockaddr_in *sa;
958 	struct mibifa *ifa;
959 	struct mibrcvaddr *rcv;
960 	u_char *ptr;
961 
962 	if (rtm->rtm_version != RTM_VERSION) {
963 		syslog(LOG_ERR, "Bogus RTM version %u", rtm->rtm_version);
964 		return;
965 	}
966 
967 	switch (rtm->rtm_type) {
968 
969 	  case RTM_NEWADDR:
970 		ifam = (struct ifa_msghdr *)rtm;
971 		mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs);
972 		if (addrs[RTAX_IFA] == NULL || addrs[RTAX_NETMASK] == NULL)
973 			break;
974 
975 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
976 		if ((ifa = mib_find_ifa(sa->sin_addr)) == NULL) {
977 			/* unknown address */
978 		    	if ((ifp = mib_find_if_sys(ifam->ifam_index)) == NULL) {
979 				syslog(LOG_WARNING, "RTM_NEWADDR for unknown "
980 				    "interface %u", ifam->ifam_index);
981 				break;
982 			}
983 		     	if ((ifa = alloc_ifa(ifp->index, sa->sin_addr)) == NULL)
984 				break;
985 		}
986 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_NETMASK];
987 		ifa->inmask = sa->sin_addr;
988 
989 		if (addrs[RTAX_BRD] != NULL) {
990 			sa = (struct sockaddr_in *)(void *)addrs[RTAX_BRD];
991 			ifa->inbcast = sa->sin_addr;
992 		}
993 		ifa->flags |= MIBIFA_FOUND;
994 		break;
995 
996 	  case RTM_DELADDR:
997 		ifam = (struct ifa_msghdr *)rtm;
998 		mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs);
999 		if (addrs[RTAX_IFA] == NULL)
1000 			break;
1001 
1002 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
1003 		if ((ifa = mib_find_ifa(sa->sin_addr)) != NULL) {
1004 			ifa->flags |= MIBIFA_FOUND;
1005 			if (!(ifa->flags & MIBIFA_DESTROYED))
1006 				destroy_ifa(ifa);
1007 		}
1008 		break;
1009 
1010 	  case RTM_NEWMADDR:
1011 		ifmam = (struct ifma_msghdr *)rtm;
1012 		mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1013 		if (addrs[RTAX_IFA] == NULL ||
1014 		    addrs[RTAX_IFA]->sa_family != AF_LINK)
1015 			break;
1016 		sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1017 		if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1018 		    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) {
1019 			/* unknown address */
1020 		    	if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) {
1021 				syslog(LOG_WARNING, "RTM_NEWMADDR for unknown "
1022 				    "interface %u", sdl->sdl_index);
1023 				break;
1024 			}
1025 		     	if ((rcv = mib_rcvaddr_create(ifp,
1026 			    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
1027 				break;
1028 			rcv->flags |= MIBRCVADDR_VOLATILE;
1029 		}
1030 		rcv->flags |= MIBRCVADDR_FOUND;
1031 		break;
1032 
1033 	  case RTM_DELMADDR:
1034 		ifmam = (struct ifma_msghdr *)rtm;
1035 		mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1036 		if (addrs[RTAX_IFA] == NULL ||
1037 		    addrs[RTAX_IFA]->sa_family != AF_LINK)
1038 			break;
1039 		sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1040 		if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1041 		    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) != NULL)
1042 			mib_rcvaddr_delete(rcv);
1043 		break;
1044 
1045 	  case RTM_IFINFO:
1046 		ifm = (struct if_msghdr *)rtm;
1047 		mib_extract_addrs(ifm->ifm_addrs, (u_char *)(ifm + 1), addrs);
1048 		if ((ifp = mib_find_if_sys(ifm->ifm_index)) == NULL)
1049 			break;
1050 		if (addrs[RTAX_IFP] != NULL &&
1051 		    addrs[RTAX_IFP]->sa_family == AF_LINK) {
1052 			sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFP];
1053 			ptr = sdl->sdl_data + sdl->sdl_nlen;
1054 			get_physaddr(ifp, sdl, ptr);
1055 		}
1056 		(void)mib_fetch_ifmib(ifp);
1057 		break;
1058 
1059 #ifdef RTM_IFANNOUNCE
1060 	  case RTM_IFANNOUNCE:
1061 		ifan = (struct if_announcemsghdr *)rtm;
1062 		ifp = mib_find_if_sys(ifan->ifan_index);
1063 
1064 		switch (ifan->ifan_what) {
1065 
1066 		  case IFAN_ARRIVAL:
1067 			if (ifp == NULL && (ifp = mibif_create(ifan->ifan_index,
1068 			    ifan->ifan_name)) != NULL) {
1069 				(void)mib_fetch_ifmib(ifp);
1070 				check_llbcast(ifp);
1071 				notify_newif(ifp);
1072 			}
1073 			break;
1074 
1075 		  case IFAN_DEPARTURE:
1076 			if (ifp != NULL)
1077 				mibif_free(ifp);
1078 			break;
1079 		}
1080 		break;
1081 #endif
1082 
1083 	  case RTM_GET:
1084 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1085 		if (rtm->rtm_flags & RTF_LLINFO) {
1086 			if (addrs[RTAX_DST] == NULL ||
1087 			    addrs[RTAX_GATEWAY] == NULL ||
1088 			    addrs[RTAX_DST]->sa_family != AF_INET ||
1089 			    addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
1090 				break;
1091 			process_arp(rtm,
1092 			    (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
1093 			    (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
1094 		} else {
1095 			if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1096 				mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1097 				    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1098 		}
1099 		break;
1100 
1101 	  case RTM_ADD:
1102 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1103 		if (rtm->rtm_flags & RTF_LLINFO) {
1104 			if (addrs[RTAX_DST] == NULL ||
1105 			    addrs[RTAX_GATEWAY] == NULL ||
1106 			    addrs[RTAX_DST]->sa_family != AF_INET ||
1107 			    addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
1108 				break;
1109 			process_arp(rtm,
1110 			    (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
1111 			    (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
1112 		} else {
1113 			if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1114 				mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1115 				    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1116 		}
1117 		break;
1118 
1119 	  case RTM_DELETE:
1120 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1121 		if (rtm->rtm_errno == 0 && !(rtm->rtm_flags & RTF_LLINFO))
1122 			mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1123 			    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1124 		break;
1125 	}
1126 }
1127 
1128 /*
1129  * send a routing message
1130  */
1131 void
1132 mib_send_rtmsg(struct rt_msghdr *rtm, struct sockaddr *gw,
1133     struct sockaddr *dst, struct sockaddr *mask)
1134 {
1135 	size_t len;
1136 	struct rt_msghdr *msg;
1137 	char *cp;
1138 	ssize_t sent;
1139 
1140 	len = sizeof(*rtm) + SA_SIZE(gw) + SA_SIZE(dst) + SA_SIZE(mask);
1141 	if ((msg = malloc(len)) == NULL) {
1142 		syslog(LOG_ERR, "%s: %m", __func__);
1143 		return;
1144 	}
1145 	cp = (char *)(msg + 1);
1146 
1147 	memset(msg, 0, sizeof(*msg));
1148 	msg->rtm_flags = 0;
1149 	msg->rtm_version = RTM_VERSION;
1150 	msg->rtm_addrs = RTA_DST | RTA_GATEWAY;
1151 
1152 	memcpy(cp, dst, SA_SIZE(dst));
1153 	cp += SA_SIZE(dst);
1154 	memcpy(cp, gw, SA_SIZE(gw));
1155 	cp += SA_SIZE(gw);
1156 	if (mask != NULL) {
1157 		memcpy(cp, mask, SA_SIZE(mask));
1158 		cp += SA_SIZE(mask);
1159 		msg->rtm_addrs |= RTA_NETMASK;
1160 	}
1161 	msg->rtm_msglen = cp - (char *)msg;
1162 	msg->rtm_type = RTM_GET;
1163 	if ((sent = write(route, msg, msg->rtm_msglen)) == -1) {
1164 		syslog(LOG_ERR, "%s: write: %m", __func__);
1165 		free(msg);
1166 		return;
1167 	}
1168 	if (sent != msg->rtm_msglen) {
1169 		syslog(LOG_ERR, "%s: short write", __func__);
1170 		free(msg);
1171 		return;
1172 	}
1173 	free(msg);
1174 }
1175 
1176 /*
1177  * Fetch the routing table via sysctl
1178  */
1179 u_char *
1180 mib_fetch_rtab(int af, int info, int arg, size_t *lenp)
1181 {
1182 	int name[6];
1183 	u_char *buf, *newbuf;
1184 
1185 	name[0] = CTL_NET;
1186 	name[1] = PF_ROUTE;
1187 	name[2] = 0;
1188 	name[3] = af;
1189 	name[4] = info;
1190 	name[5] = arg;
1191 
1192 	*lenp = 0;
1193 
1194 	/* initial estimate */
1195 	if (sysctl(name, 6, NULL, lenp, NULL, 0) == -1) {
1196 		syslog(LOG_ERR, "sysctl estimate (%d,%d,%d,%d,%d,%d): %m",
1197 		    name[0], name[1], name[2], name[3], name[4], name[5]);
1198 		return (NULL);
1199 	}
1200 	if (*lenp == 0)
1201 		return (NULL);
1202 
1203 	buf = NULL;
1204 	for (;;) {
1205 		if ((newbuf = realloc(buf, *lenp)) == NULL) {
1206 			syslog(LOG_ERR, "sysctl buffer: %m");
1207 			free(buf);
1208 			return (NULL);
1209 		}
1210 		buf = newbuf;
1211 
1212 		if (sysctl(name, 6, buf, lenp, NULL, 0) == 0)
1213 			break;
1214 
1215 		if (errno != ENOMEM) {
1216 			syslog(LOG_ERR, "sysctl get: %m");
1217 			free(buf);
1218 			return (NULL);
1219 		}
1220 		*lenp += *lenp / 8 + 1;
1221 	}
1222 
1223 	return (buf);
1224 }
1225 
1226 /*
1227  * Update the following info: interface, interface addresses, interface
1228  * receive addresses, arp-table.
1229  * This does not change the interface list itself.
1230  */
1231 static void
1232 update_ifa_info(void)
1233 {
1234 	u_char *buf, *next;
1235 	struct rt_msghdr *rtm;
1236 	struct mibifa *ifa, *ifa1;
1237 	struct mibrcvaddr *rcv, *rcv1;
1238 	size_t needed;
1239 	static const int infos[][3] = {
1240 		{ 0, NET_RT_IFLIST, 0 },
1241 #ifdef NET_RT_IFMALIST
1242 		{ AF_LINK, NET_RT_IFMALIST, 0 },
1243 #endif
1244 	};
1245 	u_int i;
1246 
1247 	TAILQ_FOREACH(ifa, &mibifa_list, link)
1248 		ifa->flags &= ~MIBIFA_FOUND;
1249 	TAILQ_FOREACH(rcv, &mibrcvaddr_list, link)
1250 		rcv->flags &= ~MIBRCVADDR_FOUND;
1251 
1252 	for (i = 0; i < sizeof(infos) / sizeof(infos[0]); i++) {
1253 		if ((buf = mib_fetch_rtab(infos[i][0], infos[i][1], infos[i][2],
1254 		   &needed)) == NULL)
1255 			continue;
1256 
1257 		next = buf;
1258 		while (next < buf + needed) {
1259 			rtm = (struct rt_msghdr *)(void *)next;
1260 			next += rtm->rtm_msglen;
1261 			handle_rtmsg(rtm);
1262 		}
1263 		free(buf);
1264 	}
1265 
1266 	/*
1267 	 * Purge the address list of unused entries. These may happen for
1268 	 * interface aliases that are on the same subnet. We don't receive
1269 	 * routing socket messages for them.
1270 	 */
1271 	ifa = TAILQ_FIRST(&mibifa_list);
1272 	while (ifa != NULL) {
1273 		ifa1 = TAILQ_NEXT(ifa, link);
1274 		if (!(ifa->flags & MIBIFA_FOUND))
1275 			destroy_ifa(ifa);
1276 		ifa = ifa1;
1277 	}
1278 
1279 	rcv = TAILQ_FIRST(&mibrcvaddr_list);
1280 	while (rcv != NULL) {
1281 		rcv1 = TAILQ_NEXT(rcv, link);
1282 		if (!(rcv->flags & (MIBRCVADDR_FOUND | MIBRCVADDR_BCAST |
1283 		    MIBRCVADDR_HW)))
1284 			mib_rcvaddr_delete(rcv);
1285 		rcv = rcv1;
1286 	}
1287 }
1288 
1289 /*
1290  * Update arp table
1291  */
1292 void
1293 mib_arp_update(void)
1294 {
1295 	struct mibarp *at, *at1;
1296 	size_t needed;
1297 	u_char *buf, *next;
1298 	struct rt_msghdr *rtm;
1299 
1300 	if (in_update_arp)
1301 		return;		/* Aaargh */
1302 	in_update_arp = 1;
1303 
1304 	TAILQ_FOREACH(at, &mibarp_list, link)
1305 		at->flags &= ~MIBARP_FOUND;
1306 
1307 	if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, RTF_LLINFO, &needed)) == NULL) {
1308 		in_update_arp = 0;
1309 		return;
1310 	}
1311 
1312 	next = buf;
1313 	while (next < buf + needed) {
1314 		rtm = (struct rt_msghdr *)(void *)next;
1315 		next += rtm->rtm_msglen;
1316 		handle_rtmsg(rtm);
1317 	}
1318 	free(buf);
1319 
1320 	at = TAILQ_FIRST(&mibarp_list);
1321 	while (at != NULL) {
1322 		at1 = TAILQ_NEXT(at, link);
1323 		if (!(at->flags & MIBARP_FOUND))
1324 			mib_arp_delete(at);
1325 		at = at1;
1326 	}
1327 	mibarpticks = get_ticks();
1328 	update_arp = 0;
1329 	in_update_arp = 0;
1330 }
1331 
1332 
1333 /*
1334  * Intput on the routing socket.
1335  */
1336 static void
1337 route_input(int fd, void *udata __unused)
1338 {
1339 	u_char	buf[1024 * 16];
1340 	ssize_t n;
1341 	struct rt_msghdr *rtm;
1342 
1343 	if ((n = read(fd, buf, sizeof(buf))) == -1)
1344 		err(1, "read(rt_socket)");
1345 
1346 	if (n == 0)
1347 		errx(1, "EOF on rt_socket");
1348 
1349 	rtm = (struct rt_msghdr *)(void *)buf;
1350 	if ((size_t)n != rtm->rtm_msglen)
1351 		errx(1, "n=%zu, rtm_msglen=%u", (size_t)n, rtm->rtm_msglen);
1352 
1353 	handle_rtmsg(rtm);
1354 }
1355 
1356 /*
1357  * execute and SIOCAIFADDR
1358  */
1359 static int
1360 siocaifaddr(char *ifname, struct in_addr addr, struct in_addr mask,
1361     struct in_addr bcast)
1362 {
1363 	struct ifaliasreq addreq;
1364 	struct sockaddr_in *sa;
1365 
1366 	memset(&addreq, 0, sizeof(addreq));
1367 	strncpy(addreq.ifra_name, ifname, sizeof(addreq.ifra_name));
1368 
1369 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_addr;
1370 	sa->sin_family = AF_INET;
1371 	sa->sin_len = sizeof(*sa);
1372 	sa->sin_addr = addr;
1373 
1374 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_mask;
1375 	sa->sin_family = AF_INET;
1376 	sa->sin_len = sizeof(*sa);
1377 	sa->sin_addr = mask;
1378 
1379 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_broadaddr;
1380 	sa->sin_family = AF_INET;
1381 	sa->sin_len = sizeof(*sa);
1382 	sa->sin_addr = bcast;
1383 
1384 	return (ioctl(mib_netsock, SIOCAIFADDR, &addreq));
1385 }
1386 
1387 /*
1388  * Exececute a SIOCDIFADDR
1389  */
1390 static int
1391 siocdifaddr(const char *ifname, struct in_addr addr)
1392 {
1393 	struct ifreq delreq;
1394 	struct sockaddr_in *sa;
1395 
1396 	memset(&delreq, 0, sizeof(delreq));
1397 	strncpy(delreq.ifr_name, ifname, sizeof(delreq.ifr_name));
1398 	sa = (struct sockaddr_in *)(void *)&delreq.ifr_addr;
1399 	sa->sin_family = AF_INET;
1400 	sa->sin_len = sizeof(*sa);
1401 	sa->sin_addr = addr;
1402 
1403 	return (ioctl(mib_netsock, SIOCDIFADDR, &delreq));
1404 }
1405 
1406 /*
1407  * Verify an interface address without fetching the entire list
1408  */
1409 static int
1410 verify_ifa(const char *name, struct mibifa *ifa)
1411 {
1412 	struct ifreq req;
1413 	struct sockaddr_in *sa;
1414 
1415 	memset(&req, 0, sizeof(req));
1416 	strncpy(req.ifr_name, name, sizeof(req.ifr_name));
1417 	sa = (struct sockaddr_in *)(void *)&req.ifr_addr;
1418 	sa->sin_family = AF_INET;
1419 	sa->sin_len = sizeof(*sa);
1420 	sa->sin_addr = ifa->inaddr;
1421 
1422 	if (ioctl(mib_netsock, SIOCGIFADDR, &req) == -1)
1423 		return (-1);
1424 	if (ifa->inaddr.s_addr != sa->sin_addr.s_addr) {
1425 		syslog(LOG_ERR, "%s: address mismatch", __func__);
1426 		return (-1);
1427 	}
1428 
1429 	if (ioctl(mib_netsock, SIOCGIFNETMASK, &req) == -1)
1430 		return (-1);
1431 	if (ifa->inmask.s_addr != sa->sin_addr.s_addr) {
1432 		syslog(LOG_ERR, "%s: netmask mismatch", __func__);
1433 		return (-1);
1434 	}
1435 	return (0);
1436 }
1437 
1438 /*
1439  * Restore a deleted interface address. Don't wait for the routing socket
1440  * to update us.
1441  */
1442 void
1443 mib_undestroy_ifa(struct mibifa *ifa)
1444 {
1445 	struct mibif *ifp;
1446 
1447 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
1448 		/* keep it destroyed */
1449 		return;
1450 
1451 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast))
1452 		/* keep it destroyed */
1453 		return;
1454 
1455 	ifa->flags &= ~MIBIFA_DESTROYED;
1456 }
1457 
1458 /*
1459  * Destroy an interface address
1460  */
1461 int
1462 mib_destroy_ifa(struct mibifa *ifa)
1463 {
1464 	struct mibif *ifp;
1465 
1466 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1467 		/* ups. */
1468 		mib_iflist_bad = 1;
1469 		return (-1);
1470 	}
1471 	if (siocdifaddr(ifp->name, ifa->inaddr)) {
1472 		/* ups. */
1473 		syslog(LOG_ERR, "SIOCDIFADDR: %m");
1474 		mib_iflist_bad = 1;
1475 		return (-1);
1476 	}
1477 	ifa->flags |= MIBIFA_DESTROYED;
1478 	return (0);
1479 }
1480 
1481 /*
1482  * Rollback the modification of an address. Don't bother to wait for
1483  * the routing socket.
1484  */
1485 void
1486 mib_unmodify_ifa(struct mibifa *ifa)
1487 {
1488 	struct mibif *ifp;
1489 
1490 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1491 		/* ups. */
1492 		mib_iflist_bad = 1;
1493 		return;
1494 	}
1495 
1496 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1497 		/* ups. */
1498 		mib_iflist_bad = 1;
1499 		return;
1500 	}
1501 }
1502 
1503 /*
1504  * Modify an IFA.
1505  */
1506 int
1507 mib_modify_ifa(struct mibifa *ifa)
1508 {
1509 	struct mibif *ifp;
1510 
1511 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1512 		/* ups. */
1513 		mib_iflist_bad = 1;
1514 		return (-1);
1515 	}
1516 
1517 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1518 		/* ups. */
1519 		mib_iflist_bad = 1;
1520 		return (-1);
1521 	}
1522 
1523 	if (verify_ifa(ifp->name, ifa)) {
1524 		/* ups. */
1525 		mib_iflist_bad = 1;
1526 		return (-1);
1527 	}
1528 
1529 	return (0);
1530 }
1531 
1532 /*
1533  * Destroy a freshly created interface address. Don't bother to wait for
1534  * the routing socket.
1535  */
1536 void
1537 mib_uncreate_ifa(struct mibifa *ifa)
1538 {
1539 	struct mibif *ifp;
1540 
1541 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1542 		/* ups. */
1543 		mib_iflist_bad = 1;
1544 		return;
1545 	}
1546 	if (siocdifaddr(ifp->name, ifa->inaddr)) {
1547 		/* ups. */
1548 		mib_iflist_bad = 1;
1549 		return;
1550 	}
1551 
1552 	destroy_ifa(ifa);
1553 }
1554 
1555 /*
1556  * Create a new ifa and verify it
1557  */
1558 struct mibifa *
1559 mib_create_ifa(u_int ifindex, struct in_addr addr, struct in_addr mask,
1560     struct in_addr bcast)
1561 {
1562 	struct mibif *ifp;
1563 	struct mibifa *ifa;
1564 
1565 	if ((ifp = mib_find_if(ifindex)) == NULL)
1566 		return (NULL);
1567 	if ((ifa = alloc_ifa(ifindex, addr)) == NULL)
1568 		return (NULL);
1569 	ifa->inmask = mask;
1570 	ifa->inbcast = bcast;
1571 
1572 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1573 		syslog(LOG_ERR, "%s: %m", __func__);
1574 		destroy_ifa(ifa);
1575 		return (NULL);
1576 	}
1577 	if (verify_ifa(ifp->name, ifa)) {
1578 		destroy_ifa(ifa);
1579 		return (NULL);
1580 	}
1581 	return (ifa);
1582 }
1583 
1584 /*
1585  * Get all cloning interfaces and make them dynamic.
1586  * Hah! Whe should probably do this on a periodic basis (XXX).
1587  */
1588 static void
1589 get_cloners(void)
1590 {
1591 	struct if_clonereq req;
1592 	char *buf, *cp;
1593 	int i;
1594 
1595 	memset(&req, 0, sizeof(req));
1596 	if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1597 		syslog(LOG_ERR, "get cloners: %m");
1598 		return;
1599 	}
1600 	if ((buf = malloc(req.ifcr_total * IFNAMSIZ)) == NULL) {
1601 		syslog(LOG_ERR, "%m");
1602 		return;
1603 	}
1604 	req.ifcr_count = req.ifcr_total;
1605 	req.ifcr_buffer = buf;
1606 	if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1607 		syslog(LOG_ERR, "get cloners: %m");
1608 		free(buf);
1609 		return;
1610 	}
1611 	for (cp = buf, i = 0; i < req.ifcr_total; i++, cp += IFNAMSIZ)
1612 		mib_if_set_dyn(cp);
1613 	free(buf);
1614 }
1615 
1616 /*
1617  * Idle function
1618  */
1619 static void
1620 mibII_idle(void)
1621 {
1622 	struct mibifa *ifa;
1623 
1624 	if (mib_iflist_bad) {
1625 		TAILQ_FOREACH(ifa, &mibifa_list, link)
1626 			ifa->flags &= ~MIBIFA_DESTROYED;
1627 
1628 		/* assume, that all cloning interfaces are dynamic */
1629 		get_cloners();
1630 
1631 		mib_refresh_iflist();
1632 		update_ifa_info();
1633 		mib_arp_update();
1634 		mib_iflist_bad = 0;
1635 	}
1636 	if (update_arp)
1637 		mib_arp_update();
1638 }
1639 
1640 
1641 /*
1642  * Start the module
1643  */
1644 static void
1645 mibII_start(void)
1646 {
1647 	if ((route_fd = fd_select(route, route_input, NULL, module)) == NULL) {
1648 		syslog(LOG_ERR, "fd_select(route): %m");
1649 		return;
1650 	}
1651 	mib_refresh_iflist();
1652 	update_ifa_info();
1653 	mib_arp_update();
1654 	(void)mib_fetch_route();
1655 	mib_iftable_last_change = 0;
1656 	mib_ifstack_last_change = 0;
1657 
1658 	ifmib_reg = or_register(&oid_ifMIB,
1659 	    "The MIB module to describe generic objects for network interface"
1660 	    " sub-layers.", module);
1661 
1662 	ipmib_reg = or_register(&oid_ipMIB,
1663 	   "The MIB module for managing IP and ICMP implementations, but "
1664 	   "excluding their management of IP routes.", module);
1665 
1666 	tcpmib_reg = or_register(&oid_tcpMIB,
1667 	   "The MIB module for managing TCP implementations.", module);
1668 
1669 	udpmib_reg = or_register(&oid_udpMIB,
1670 	   "The MIB module for managing UDP implementations.", module);
1671 
1672 	ipForward_reg = or_register(&oid_ipForward,
1673 	   "The MIB module for the display of CIDR multipath IP Routes.",
1674 	   module);
1675 }
1676 
1677 /*
1678  * Initialize the module
1679  */
1680 static int
1681 mibII_init(struct lmodule *mod, int argc __unused, char *argv[] __unused)
1682 {
1683 	size_t len;
1684 
1685 	module = mod;
1686 
1687 	len = sizeof(clockinfo);
1688 	if (sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0) == -1) {
1689 		syslog(LOG_ERR, "kern.clockrate: %m");
1690 		return (-1);
1691 	}
1692 	if (len != sizeof(clockinfo)) {
1693 		syslog(LOG_ERR, "kern.clockrate: wrong size");
1694 		return (-1);
1695 	}
1696 
1697 	if ((route = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) == -1) {
1698 		syslog(LOG_ERR, "PF_ROUTE: %m");
1699 		return (-1);
1700 	}
1701 
1702 	if ((mib_netsock = socket(PF_INET, SOCK_DGRAM, 0)) == -1) {
1703 		syslog(LOG_ERR, "PF_INET: %m");
1704 		(void)close(route);
1705 		return (-1);
1706 	}
1707 	(void)shutdown(mib_netsock, SHUT_RDWR);
1708 
1709 	/* assume, that all cloning interfaces are dynamic */
1710 	get_cloners();
1711 
1712 	return (0);
1713 }
1714 
1715 static int
1716 mibII_fini(void)
1717 {
1718 	if (route_fd != NULL)
1719 		fd_deselect(route_fd);
1720 	if (route != -1)
1721 		(void)close(route);
1722 	if (mib_netsock != -1)
1723 		(void)close(mib_netsock);
1724 	/* XXX free memory */
1725 
1726 	or_unregister(ipForward_reg);
1727 	or_unregister(udpmib_reg);
1728 	or_unregister(tcpmib_reg);
1729 	or_unregister(ipmib_reg);
1730 	or_unregister(ifmib_reg);
1731 
1732 	return (0);
1733 }
1734 
1735 static void
1736 mibII_loading(const struct lmodule *mod, int loaded)
1737 {
1738 	struct mibif *ifp;
1739 
1740 	if (loaded == 1)
1741 		return;
1742 
1743 	TAILQ_FOREACH(ifp, &mibif_list, link)
1744 		if (ifp->xnotify_mod == mod) {
1745 			ifp->xnotify_mod = NULL;
1746 			ifp->xnotify_data = NULL;
1747 			ifp->xnotify = NULL;
1748 		}
1749 
1750 	mib_unregister_newif(mod);
1751 }
1752 
1753 const struct snmp_module config = {
1754 	"This module implements the interface and ip groups.",
1755 	mibII_init,
1756 	mibII_fini,
1757 	mibII_idle,	/* idle */
1758 	NULL,		/* dump */
1759 	NULL,		/* config */
1760 	mibII_start,
1761 	NULL,
1762 	mibII_ctree,
1763 	mibII_CTREE_SIZE,
1764 	mibII_loading
1765 };
1766 
1767 /*
1768  * Should have a list of these attached to each interface.
1769  */
1770 void *
1771 mibif_notify(struct mibif *ifp, const struct lmodule *mod,
1772     mibif_notify_f func, void *data)
1773 {
1774 	ifp->xnotify = func;
1775 	ifp->xnotify_data = data;
1776 	ifp->xnotify_mod = mod;
1777 
1778 	return (ifp);
1779 }
1780 
1781 void
1782 mibif_unnotify(void *arg)
1783 {
1784 	struct mibif *ifp = arg;
1785 
1786 	ifp->xnotify = NULL;
1787 	ifp->xnotify_data = NULL;
1788 	ifp->xnotify_mod = NULL;
1789 }
1790