xref: /freebsd/contrib/bsnmp/snmp_mibII/mibII.c (revision 2be1a816)
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: mibII.c 516 2006-10-27 15:54:02Z brandt_h $
30  *
31  * Implementation of the standard interfaces and ip MIB.
32  */
33 #include "mibII.h"
34 #include "mibII_oid.h"
35 #include <net/if.h>
36 #include <net/if_types.h>
37 
38 
39 /*****************************/
40 
41 /* our module */
42 static struct lmodule *module;
43 
44 /* routing socket */
45 static int route;
46 static void *route_fd;
47 
48 /* if-index allocator */
49 static uint32_t next_if_index = 1;
50 
51 /* re-fetch arp table */
52 static int update_arp;
53 static int in_update_arp;
54 
55 /* OR registrations */
56 static u_int ifmib_reg;
57 static u_int ipmib_reg;
58 static u_int tcpmib_reg;
59 static u_int udpmib_reg;
60 static u_int ipForward_reg;
61 
62 /*****************************/
63 
64 /* list of all IP addresses */
65 struct mibifa_list mibifa_list = TAILQ_HEAD_INITIALIZER(mibifa_list);
66 
67 /* list of all interfaces */
68 struct mibif_list mibif_list = TAILQ_HEAD_INITIALIZER(mibif_list);
69 
70 /* list of dynamic interface names */
71 struct mibdynif_list mibdynif_list = SLIST_HEAD_INITIALIZER(mibdynif_list);
72 
73 /* list of all interface index mappings */
74 struct mibindexmap_list mibindexmap_list = STAILQ_HEAD_INITIALIZER(mibindexmap_list);
75 
76 /* list of all stacking entries */
77 struct mibifstack_list mibifstack_list = TAILQ_HEAD_INITIALIZER(mibifstack_list);
78 
79 /* list of all receive addresses */
80 struct mibrcvaddr_list mibrcvaddr_list = TAILQ_HEAD_INITIALIZER(mibrcvaddr_list);
81 
82 /* list of all NetToMedia entries */
83 struct mibarp_list mibarp_list = TAILQ_HEAD_INITIALIZER(mibarp_list);
84 
85 /* number of interfaces */
86 int32_t mib_if_number;
87 
88 /* last change of table */
89 uint64_t mib_iftable_last_change;
90 
91 /* last change of stack table */
92 uint64_t mib_ifstack_last_change;
93 
94 /* if this is set, one of our lists may be bad. refresh them when idle */
95 int mib_iflist_bad;
96 
97 /* network socket */
98 int mib_netsock;
99 
100 /* last time refreshed */
101 uint64_t mibarpticks;
102 
103 /* info on system clocks */
104 struct clockinfo clockinfo;
105 
106 /* list of all New if registrations */
107 static struct newifreg_list newifreg_list = TAILQ_HEAD_INITIALIZER(newifreg_list);
108 
109 /* baud rate of fastest interface */
110 uint64_t mibif_maxspeed;
111 
112 /* user-forced update interval */
113 u_int mibif_force_hc_update_interval;
114 
115 /* current update interval */
116 u_int mibif_hc_update_interval;
117 
118 /* HC update timer handle */
119 static void *hc_update_timer;
120 
121 /*****************************/
122 
123 static const struct asn_oid oid_ifMIB = OIDX_ifMIB;
124 static const struct asn_oid oid_ipMIB = OIDX_ipMIB;
125 static const struct asn_oid oid_tcpMIB = OIDX_tcpMIB;
126 static const struct asn_oid oid_udpMIB = OIDX_udpMIB;
127 static const struct asn_oid oid_ipForward = OIDX_ipForward;
128 static const struct asn_oid oid_linkDown = OIDX_linkDown;
129 static const struct asn_oid oid_linkUp = OIDX_linkUp;
130 static const struct asn_oid oid_ifIndex = OIDX_ifIndex;
131 
132 /*****************************/
133 
134 /*
135  * Find an interface
136  */
137 struct mibif *
138 mib_find_if(u_int idx)
139 {
140 	struct mibif *ifp;
141 
142 	TAILQ_FOREACH(ifp, &mibif_list, link)
143 		if (ifp->index == idx)
144 			return (ifp);
145 	return (NULL);
146 }
147 
148 struct mibif *
149 mib_find_if_sys(u_int sysindex)
150 {
151 	struct mibif *ifp;
152 
153 	TAILQ_FOREACH(ifp, &mibif_list, link)
154 		if (ifp->sysindex == sysindex)
155 			return (ifp);
156 	return (NULL);
157 }
158 
159 struct mibif *
160 mib_find_if_name(const char *name)
161 {
162 	struct mibif *ifp;
163 
164 	TAILQ_FOREACH(ifp, &mibif_list, link)
165 		if (strcmp(ifp->name, name) == 0)
166 			return (ifp);
167 	return (NULL);
168 }
169 
170 /*
171  * Check whether an interface is dynamic. The argument may include the
172  * unit number. This assumes, that the name part does NOT contain digits.
173  */
174 int
175 mib_if_is_dyn(const char *name)
176 {
177 	size_t len;
178 	struct mibdynif *d;
179 
180 	for (len = 0; name[len] != '\0' && isalpha(name[len]) ; len++)
181 		;
182 	SLIST_FOREACH(d, &mibdynif_list, link)
183 		if (strlen(d->name) == len && strncmp(d->name, name, len) == 0)
184 			return (1);
185 	return (0);
186 }
187 
188 /* set an interface name to dynamic mode */
189 void
190 mib_if_set_dyn(const char *name)
191 {
192 	struct mibdynif *d;
193 
194 	SLIST_FOREACH(d, &mibdynif_list, link)
195 		if (strcmp(name, d->name) == 0)
196 			return;
197 	if ((d = malloc(sizeof(*d))) == NULL)
198 		err(1, NULL);
199 	strcpy(d->name, name);
200 	SLIST_INSERT_HEAD(&mibdynif_list, d, link);
201 }
202 
203 /*
204  * register for interface creations
205  */
206 int
207 mib_register_newif(int (*func)(struct mibif *), const struct lmodule *mod)
208 {
209 	struct newifreg *reg;
210 
211 	TAILQ_FOREACH(reg, &newifreg_list, link)
212 		if (reg->mod == mod) {
213 			reg->func = func;
214 			return (0);
215 		}
216 	if ((reg = malloc(sizeof(*reg))) == NULL) {
217 		syslog(LOG_ERR, "newifreg: %m");
218 		return (-1);
219 	}
220 	reg->mod = mod;
221 	reg->func = func;
222 	TAILQ_INSERT_TAIL(&newifreg_list, reg, link);
223 
224 	return (0);
225 }
226 
227 void
228 mib_unregister_newif(const struct lmodule *mod)
229 {
230 	struct newifreg *reg;
231 
232 	TAILQ_FOREACH(reg, &newifreg_list, link)
233 		if (reg->mod == mod) {
234 			TAILQ_REMOVE(&newifreg_list, reg, link);
235 			free(reg);
236 			return;
237 		}
238 
239 }
240 
241 struct mibif *
242 mib_first_if(void)
243 {
244 	return (TAILQ_FIRST(&mibif_list));
245 }
246 struct mibif *
247 mib_next_if(const struct mibif *ifp)
248 {
249 	return (TAILQ_NEXT(ifp, link));
250 }
251 
252 /*
253  * Change the admin status of an interface
254  */
255 int
256 mib_if_admin(struct mibif *ifp, int up)
257 {
258 	struct ifreq ifr;
259 
260 	strncpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
261 	if (ioctl(mib_netsock, SIOCGIFFLAGS, &ifr) == -1) {
262 		syslog(LOG_ERR, "SIOCGIFFLAGS(%s): %m", ifp->name);
263 		return (-1);
264 	}
265 	if (up)
266 		ifr.ifr_flags |= IFF_UP;
267 	else
268 		ifr.ifr_flags &= ~IFF_UP;
269 	if (ioctl(mib_netsock, SIOCSIFFLAGS, &ifr) == -1) {
270 		syslog(LOG_ERR, "SIOCSIFFLAGS(%s): %m", ifp->name);
271 		return (-1);
272 	}
273 
274 	(void)mib_fetch_ifmib(ifp);
275 
276 	return (0);
277 }
278 
279 /*
280  * Generate a link up/down trap
281  */
282 static void
283 link_trap(struct mibif *ifp, int up)
284 {
285 	struct snmp_value ifindex;
286 
287 	ifindex.var = oid_ifIndex;
288 	ifindex.var.subs[ifindex.var.len++] = ifp->index;
289 	ifindex.syntax = SNMP_SYNTAX_INTEGER;
290 	ifindex.v.integer = ifp->index;
291 
292 	snmp_send_trap(up ? &oid_linkUp : &oid_linkDown, &ifindex,
293 	    (struct snmp_value *)NULL);
294 }
295 
296 /**
297  * Fetch the GENERIC IFMIB and update the HC counters
298  */
299 static int
300 fetch_generic_mib(struct mibif *ifp, const struct ifmibdata *old)
301 {
302 	int name[6];
303 	size_t len;
304 	struct mibif_private *p = ifp->private;
305 
306 	name[0] = CTL_NET;
307 	name[1] = PF_LINK;
308 	name[2] = NETLINK_GENERIC;
309 	name[3] = IFMIB_IFDATA;
310 	name[4] = ifp->sysindex;
311 	name[5] = IFDATA_GENERAL;
312 
313 	len = sizeof(ifp->mib);
314 	if (sysctl(name, 6, &ifp->mib, &len, NULL, 0) == -1) {
315 		if (errno != ENOENT)
316 			syslog(LOG_WARNING, "sysctl(ifmib, %s) failed %m",
317 			    ifp->name);
318 		return (-1);
319 	}
320 
321 	/*
322 	 * Assume that one of the two following compounds is optimized away
323 	 */
324 	if (ULONG_MAX >= 0xffffffffffffffffULL) {
325 		p->hc_inoctets = ifp->mib.ifmd_data.ifi_ibytes;
326 		p->hc_outoctets = ifp->mib.ifmd_data.ifi_obytes;
327 		p->hc_omcasts = ifp->mib.ifmd_data.ifi_omcasts;
328 		p->hc_opackets = ifp->mib.ifmd_data.ifi_opackets;
329 		p->hc_imcasts = ifp->mib.ifmd_data.ifi_imcasts;
330 		p->hc_ipackets = ifp->mib.ifmd_data.ifi_ipackets;
331 
332 	} else if (ULONG_MAX >= 0xffffffff) {
333 
334 #define	UPDATE(HC, MIB)							\
335 		if (old->ifmd_data.MIB > ifp->mib.ifmd_data.MIB)	\
336 			p->HC += (0x100000000ULL +			\
337 			    ifp->mib.ifmd_data.MIB) -			\
338 			    old->ifmd_data.MIB;				\
339 		else							\
340 			p->HC += ifp->mib.ifmd_data.MIB -		\
341 			    old->ifmd_data.MIB;
342 
343 		UPDATE(hc_inoctets, ifi_ibytes)
344 		UPDATE(hc_outoctets, ifi_obytes)
345 		UPDATE(hc_omcasts, ifi_omcasts)
346 		UPDATE(hc_opackets, ifi_opackets)
347 		UPDATE(hc_imcasts, ifi_imcasts)
348 		UPDATE(hc_ipackets, ifi_ipackets)
349 
350 #undef	UPDATE
351 	} else
352 		abort();
353 	return (0);
354 }
355 
356 /**
357  * Update the 64-bit interface counters
358  */
359 static void
360 update_hc_counters(void *arg __unused)
361 {
362 	struct mibif *ifp;
363 	struct ifmibdata oldmib;
364 
365 	TAILQ_FOREACH(ifp, &mibif_list, link) {
366 		oldmib = ifp->mib;
367 		(void)fetch_generic_mib(ifp, &oldmib);
368 	}
369 }
370 
371 /**
372  * Recompute the poll timer for the HC counters
373  */
374 void
375 mibif_reset_hc_timer(void)
376 {
377 	u_int ticks;
378 
379 	if ((ticks = mibif_force_hc_update_interval) == 0) {
380 		if (mibif_maxspeed <= IF_Mbps(10)) {
381 			/* at 10Mbps overflow needs 3436 seconds */
382 			ticks = 3000 * 100;	/* 50 minutes */
383 		} else if (mibif_maxspeed <= IF_Mbps(100)) {
384 			/* at 100Mbps overflow needs 343 seconds */
385 			ticks = 300 * 100;	/* 5 minutes */
386 		} else if (mibif_maxspeed < IF_Mbps(622)) {
387 			/* at 622Mbps overflow needs 53 seconds */
388 			ticks = 40 * 100;	/* 40 seconds */
389 		} else if (mibif_maxspeed <= IF_Mbps(1000)) {
390 			/* at 1Gbps overflow needs  34 seconds */
391 			ticks = 20 * 100;	/* 20 seconds */
392 		} else {
393 			/* at 10Gbps overflow needs 3.4 seconds */
394 			ticks = 100;		/* 1 seconds */
395 		}
396 	}
397 
398 	if (ticks == mibif_hc_update_interval)
399 		return;
400 
401 	if (hc_update_timer != NULL) {
402 		timer_stop(hc_update_timer);
403 		hc_update_timer = NULL;
404 	}
405 	update_hc_counters(NULL);
406 	if ((hc_update_timer = timer_start_repeat(ticks * 10, ticks * 10,
407 	    update_hc_counters, NULL, module)) == NULL) {
408 		syslog(LOG_ERR, "timer_start(%u): %m", ticks);
409 		return;
410 	}
411 	mibif_hc_update_interval = ticks;
412 }
413 
414 /*
415  * Fetch new MIB data.
416  */
417 int
418 mib_fetch_ifmib(struct mibif *ifp)
419 {
420 	int name[6];
421 	size_t len;
422 	void *newmib;
423 	struct ifmibdata oldmib = ifp->mib;
424 
425 	if (fetch_generic_mib(ifp, &oldmib) == -1)
426 		return (-1);
427 
428 	/*
429 	 * Quoting RFC2863, 3.1.15: "... LinkUp and linkDown traps are
430 	 * generated just after ifOperStatus leaves, or just before it
431 	 * enters, the down state, respectively;"
432 	 */
433 	if (ifp->trap_enable && ifp->mib.ifmd_data.ifi_link_state !=
434 	    oldmib.ifmd_data.ifi_link_state &&
435 	    (ifp->mib.ifmd_data.ifi_link_state == LINK_STATE_DOWN ||
436 	    oldmib.ifmd_data.ifi_link_state == LINK_STATE_DOWN))
437 		link_trap(ifp, ifp->mib.ifmd_data.ifi_link_state ==
438 		    LINK_STATE_UP ? 1 : 0);
439 
440 	ifp->flags &= ~(MIBIF_HIGHSPEED | MIBIF_VERYHIGHSPEED);
441 	if (ifp->mib.ifmd_data.ifi_baudrate > 20000000) {
442 		ifp->flags |= MIBIF_HIGHSPEED;
443 		if (ifp->mib.ifmd_data.ifi_baudrate > 650000000)
444 			ifp->flags |= MIBIF_VERYHIGHSPEED;
445 	}
446 	if (ifp->mib.ifmd_data.ifi_baudrate > mibif_maxspeed) {
447 		mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
448 		mibif_reset_hc_timer();
449 	}
450 
451 	/*
452 	 * linkspecific MIB
453 	 */
454 	name[0] = CTL_NET;
455 	name[1] = PF_LINK;
456 	name[2] = NETLINK_GENERIC;
457 	name[3] = IFMIB_IFDATA;
458 	name[4] = ifp->sysindex;
459 	name[5] = IFDATA_LINKSPECIFIC;
460 	if (sysctl(name, 6, NULL, &len, NULL, 0) == -1) {
461 		syslog(LOG_WARNING, "sysctl linkmib estimate (%s): %m",
462 		    ifp->name);
463 		if (ifp->specmib != NULL) {
464 			ifp->specmib = NULL;
465 			ifp->specmiblen = 0;
466 		}
467 		goto out;
468 	}
469 	if (len == 0) {
470 		if (ifp->specmib != NULL) {
471 			ifp->specmib = NULL;
472 			ifp->specmiblen = 0;
473 		}
474 		goto out;
475 	}
476 
477 	if (ifp->specmiblen != len) {
478 		if ((newmib = realloc(ifp->specmib, len)) == NULL) {
479 			ifp->specmib = NULL;
480 			ifp->specmiblen = 0;
481 			goto out;
482 		}
483 		ifp->specmib = newmib;
484 		ifp->specmiblen = len;
485 	}
486 	if (sysctl(name, 6, ifp->specmib, &len, NULL, 0) == -1) {
487 		syslog(LOG_WARNING, "sysctl linkmib (%s): %m", ifp->name);
488 		if (ifp->specmib != NULL) {
489 			ifp->specmib = NULL;
490 			ifp->specmiblen = 0;
491 		}
492 	}
493 
494   out:
495 	ifp->mibtick = get_ticks();
496 	return (0);
497 }
498 
499 /* find first/next address for a given interface */
500 struct mibifa *
501 mib_first_ififa(const struct mibif *ifp)
502 {
503 	struct mibifa *ifa;
504 
505 	TAILQ_FOREACH(ifa, &mibifa_list, link)
506 		if (ifp->index == ifa->ifindex)
507 			return (ifa);
508 	return (NULL);
509 }
510 
511 struct mibifa *
512 mib_next_ififa(struct mibifa *ifa0)
513 {
514 	struct mibifa *ifa;
515 
516 	ifa = ifa0;
517 	while ((ifa = TAILQ_NEXT(ifa, link)) != NULL)
518 		if (ifa->ifindex == ifa0->ifindex)
519 			return (ifa);
520 	return (NULL);
521 }
522 
523 /*
524  * Allocate a new IFA
525  */
526 static struct mibifa *
527 alloc_ifa(u_int ifindex, struct in_addr addr)
528 {
529 	struct mibifa *ifa;
530 	uint32_t ha;
531 
532 	if ((ifa = malloc(sizeof(struct mibifa))) == NULL) {
533 		syslog(LOG_ERR, "ifa: %m");
534 		return (NULL);
535 	}
536 	ifa->inaddr = addr;
537 	ifa->ifindex = ifindex;
538 
539 	ha = ntohl(ifa->inaddr.s_addr);
540 	ifa->index.len = 4;
541 	ifa->index.subs[0] = (ha >> 24) & 0xff;
542 	ifa->index.subs[1] = (ha >> 16) & 0xff;
543 	ifa->index.subs[2] = (ha >>  8) & 0xff;
544 	ifa->index.subs[3] = (ha >>  0) & 0xff;
545 
546 	ifa->flags = 0;
547 	ifa->inbcast.s_addr = 0;
548 	ifa->inmask.s_addr = 0xffffffff;
549 
550 	INSERT_OBJECT_OID(ifa, &mibifa_list);
551 
552 	return (ifa);
553 }
554 
555 /*
556  * Delete an interface address
557  */
558 static void
559 destroy_ifa(struct mibifa *ifa)
560 {
561 	TAILQ_REMOVE(&mibifa_list, ifa, link);
562 	free(ifa);
563 }
564 
565 
566 /*
567  * Helper routine to extract the sockaddr structures from a routing
568  * socket message.
569  */
570 void
571 mib_extract_addrs(int addrs, u_char *info, struct sockaddr **out)
572 {
573 	u_int i;
574 
575 	for (i = 0; i < RTAX_MAX; i++) {
576 		if ((addrs & (1 << i)) != 0) {
577 			*out = (struct sockaddr *)(void *)info;
578 			info += roundup((*out)->sa_len, sizeof(long));
579 		} else
580 			*out = NULL;
581 		out++;
582 	}
583 }
584 
585 /*
586  * save the phys address of an interface. Handle receive address entries here.
587  */
588 static void
589 get_physaddr(struct mibif *ifp, struct sockaddr_dl *sdl, u_char *ptr)
590 {
591 	u_char *np;
592 	struct mibrcvaddr *rcv;
593 
594 	if (sdl->sdl_alen == 0) {
595 		/* no address */
596 		if (ifp->physaddrlen != 0) {
597 			if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
598 			    ifp->physaddrlen)) != NULL)
599 				mib_rcvaddr_delete(rcv);
600 			free(ifp->physaddr);
601 			ifp->physaddr = NULL;
602 			ifp->physaddrlen = 0;
603 		}
604 		return;
605 	}
606 
607 	if (ifp->physaddrlen != sdl->sdl_alen) {
608 		/* length changed */
609 		if (ifp->physaddrlen) {
610 			/* delete olf receive address */
611 			if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
612 			    ifp->physaddrlen)) != NULL)
613 				mib_rcvaddr_delete(rcv);
614 		}
615 		if ((np = realloc(ifp->physaddr, sdl->sdl_alen)) == NULL) {
616 			free(ifp->physaddr);
617 			ifp->physaddr = NULL;
618 			ifp->physaddrlen = 0;
619 			return;
620 		}
621 		ifp->physaddr = np;
622 		ifp->physaddrlen = sdl->sdl_alen;
623 
624 	} else if (memcmp(ifp->physaddr, ptr, ifp->physaddrlen) == 0) {
625 		/* no change */
626 		return;
627 
628 	} else {
629 		/* address changed */
630 
631 		/* delete olf receive address */
632 		if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
633 		    ifp->physaddrlen)) != NULL)
634 			mib_rcvaddr_delete(rcv);
635 	}
636 
637 	memcpy(ifp->physaddr, ptr, ifp->physaddrlen);
638 
639 	/* make new receive address */
640 	if ((rcv = mib_rcvaddr_create(ifp, ifp->physaddr, ifp->physaddrlen)) != NULL)
641 		rcv->flags |= MIBRCVADDR_HW;
642 }
643 
644 /*
645  * Free an interface
646  */
647 static void
648 mibif_free(struct mibif *ifp)
649 {
650 	struct mibif *ifp1;
651 	struct mibindexmap *map;
652 	struct mibifa *ifa, *ifa1;
653 	struct mibrcvaddr *rcv, *rcv1;
654 	struct mibarp *at, *at1;
655 
656 	if (ifp->xnotify != NULL)
657 		(*ifp->xnotify)(ifp, MIBIF_NOTIFY_DESTROY, ifp->xnotify_data);
658 
659 	(void)mib_ifstack_delete(ifp, NULL);
660 	(void)mib_ifstack_delete(NULL, ifp);
661 
662 	TAILQ_REMOVE(&mibif_list, ifp, link);
663 
664 	/* if this was the fastest interface - recompute this */
665 	if (ifp->mib.ifmd_data.ifi_baudrate == mibif_maxspeed) {
666 		mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
667 		TAILQ_FOREACH(ifp1, &mibif_list, link)
668 			if (ifp1->mib.ifmd_data.ifi_baudrate > mibif_maxspeed)
669 				mibif_maxspeed =
670 				    ifp1->mib.ifmd_data.ifi_baudrate;
671 		mibif_reset_hc_timer();
672 	}
673 
674 	free(ifp->private);
675 	if (ifp->physaddr != NULL)
676 		free(ifp->physaddr);
677 	if (ifp->specmib != NULL)
678 		free(ifp->specmib);
679 
680 	STAILQ_FOREACH(map, &mibindexmap_list, link)
681 		if (map->mibif == ifp) {
682 			map->mibif = NULL;
683 			break;
684 		}
685 
686 	/* purge interface addresses */
687 	ifa = TAILQ_FIRST(&mibifa_list);
688 	while (ifa != NULL) {
689 		ifa1 = TAILQ_NEXT(ifa, link);
690 		if (ifa->ifindex == ifp->index)
691 			destroy_ifa(ifa);
692 		ifa = ifa1;
693 	}
694 
695 	/* purge receive addresses */
696 	rcv = TAILQ_FIRST(&mibrcvaddr_list);
697 	while (rcv != NULL) {
698 		rcv1 = TAILQ_NEXT(rcv, link);
699 		if (rcv->ifindex == ifp->index)
700 			mib_rcvaddr_delete(rcv);
701 		rcv = rcv1;
702 	}
703 
704 	/* purge ARP entries */
705 	at = TAILQ_FIRST(&mibarp_list);
706 	while (at != NULL) {
707 		at1 = TAILQ_NEXT(at, link);
708 		if (at->index.subs[0] == ifp->index)
709 			mib_arp_delete(at);
710 		at = at1;
711 	}
712 
713 
714 	free(ifp);
715 	mib_if_number--;
716 	mib_iftable_last_change = this_tick;
717 }
718 
719 /*
720  * Create a new interface
721  */
722 static struct mibif *
723 mibif_create(u_int sysindex, const char *name)
724 {
725 	struct mibif *ifp;
726 	struct mibindexmap *map;
727 
728 	if ((ifp = malloc(sizeof(*ifp))) == NULL) {
729 		syslog(LOG_WARNING, "%s: %m", __func__);
730 		return (NULL);
731 	}
732 	memset(ifp, 0, sizeof(*ifp));
733 	if ((ifp->private = malloc(sizeof(struct mibif_private))) == NULL) {
734 		syslog(LOG_WARNING, "%s: %m", __func__);
735 		free(ifp);
736 		return (NULL);
737 	}
738 	memset(ifp->private, 0, sizeof(struct mibif_private));
739 
740 	ifp->sysindex = sysindex;
741 	strcpy(ifp->name, name);
742 	strcpy(ifp->descr, name);
743 	ifp->spec_oid = oid_zeroDotZero;
744 
745 	map = NULL;
746 	if (!mib_if_is_dyn(ifp->name)) {
747 		/* non-dynamic. look whether we know the interface */
748 		STAILQ_FOREACH(map, &mibindexmap_list, link)
749 			if (strcmp(map->name, ifp->name) == 0) {
750 				ifp->index = map->ifindex;
751 				map->mibif = ifp;
752 				break;
753 			}
754 		/* assume it has a connector if it is not dynamic */
755 		ifp->has_connector = 1;
756 		ifp->trap_enable = 1;
757 	}
758 	if (map == NULL) {
759 		/* new interface - get new index */
760 		if (next_if_index > 0x7fffffff)
761 			errx(1, "ifindex wrap");
762 
763 		if ((map = malloc(sizeof(*map))) == NULL) {
764 			syslog(LOG_ERR, "ifmap: %m");
765 			free(ifp);
766 			return (NULL);
767 		}
768 		map->ifindex = next_if_index++;
769 		map->sysindex = ifp->sysindex;
770 		strcpy(map->name, ifp->name);
771 		map->mibif = ifp;
772 		STAILQ_INSERT_TAIL(&mibindexmap_list, map, link);
773 	} else {
774 		/* re-instantiate. Introduce a counter discontinuity */
775 		ifp->counter_disc = get_ticks();
776 	}
777 	ifp->index = map->ifindex;
778 	ifp->mib.ifmd_data.ifi_link_state = LINK_STATE_UNKNOWN;
779 
780 	INSERT_OBJECT_INT(ifp, &mibif_list);
781 	mib_if_number++;
782 	mib_iftable_last_change = this_tick;
783 
784 	/* instantiate default ifStack entries */
785 	(void)mib_ifstack_create(ifp, NULL);
786 	(void)mib_ifstack_create(NULL, ifp);
787 
788 	return (ifp);
789 }
790 
791 /*
792  * Inform all interested parties about a new interface
793  */
794 static void
795 notify_newif(struct mibif *ifp)
796 {
797 	struct newifreg *reg;
798 
799 	TAILQ_FOREACH(reg, &newifreg_list, link)
800 		if ((*reg->func)(ifp))
801 			return;
802 }
803 
804 /*
805  * This is called for new interfaces after we have fetched the interface
806  * MIB. If this is a broadcast interface try to guess the broadcast address
807  * depending on the interface type.
808  */
809 static void
810 check_llbcast(struct mibif *ifp)
811 {
812 	static u_char ether_bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
813 	static u_char arcnet_bcast = 0;
814 	struct mibrcvaddr *rcv;
815 
816 	if (!(ifp->mib.ifmd_flags & IFF_BROADCAST))
817 		return;
818 
819 	switch (ifp->mib.ifmd_data.ifi_type) {
820 
821 	  case IFT_ETHER:
822 	  case IFT_FDDI:
823 	  case IFT_ISO88025:
824 		if (mib_find_rcvaddr(ifp->index, ether_bcast, 6) == NULL &&
825 		    (rcv = mib_rcvaddr_create(ifp, ether_bcast, 6)) != NULL)
826 			rcv->flags |= MIBRCVADDR_BCAST;
827 		break;
828 
829 	  case IFT_ARCNET:
830 		if (mib_find_rcvaddr(ifp->index, &arcnet_bcast, 1) == NULL &&
831 		    (rcv = mib_rcvaddr_create(ifp, &arcnet_bcast, 1)) != NULL)
832 			rcv->flags |= MIBRCVADDR_BCAST;
833 		break;
834 	}
835 }
836 
837 
838 /*
839  * Retrieve the current interface list from the system.
840  */
841 void
842 mib_refresh_iflist(void)
843 {
844 	struct mibif *ifp, *ifp1;
845 	size_t len;
846 	u_short idx;
847 	int name[6];
848 	int count;
849 	struct ifmibdata mib;
850 
851 	TAILQ_FOREACH(ifp, &mibif_list, link)
852 		ifp->flags &= ~MIBIF_FOUND;
853 
854 	len = sizeof(count);
855 	if (sysctlbyname("net.link.generic.system.ifcount", &count, &len,
856 	    NULL, 0) == -1) {
857 		syslog(LOG_ERR, "ifcount: %m");
858 		return;
859 	}
860 	name[0] = CTL_NET;
861 	name[1] = PF_LINK;
862 	name[2] = NETLINK_GENERIC;
863 	name[3] = IFMIB_IFDATA;
864 	name[5] = IFDATA_GENERAL;
865 	for (idx = 1; idx <= count; idx++) {
866 		name[4] = idx;
867 		len = sizeof(mib);
868 		if (sysctl(name, 6, &mib, &len, NULL, 0) == -1) {
869 			if (errno == ENOENT)
870 				continue;
871 			syslog(LOG_ERR, "ifmib(%u): %m", idx);
872 			return;
873 		}
874 		if ((ifp = mib_find_if_sys(idx)) != NULL) {
875 			ifp->flags |= MIBIF_FOUND;
876 			continue;
877 		}
878 		/* Unknown interface - create */
879 		if ((ifp = mibif_create(idx, mib.ifmd_name)) != NULL) {
880 			ifp->flags |= MIBIF_FOUND;
881 			(void)mib_fetch_ifmib(ifp);
882 			check_llbcast(ifp);
883 			notify_newif(ifp);
884 		}
885 	}
886 
887 	/*
888 	 * Purge interfaces that disappeared
889 	 */
890 	ifp = TAILQ_FIRST(&mibif_list);
891 	while (ifp != NULL) {
892 		ifp1 = TAILQ_NEXT(ifp, link);
893 		if (!(ifp->flags & MIBIF_FOUND))
894 			mibif_free(ifp);
895 		ifp = ifp1;
896 	}
897 }
898 
899 /*
900  * Find an interface address
901  */
902 struct mibifa *
903 mib_find_ifa(struct in_addr addr)
904 {
905 	struct mibifa *ifa;
906 
907 	TAILQ_FOREACH(ifa, &mibifa_list, link)
908 		if (ifa->inaddr.s_addr == addr.s_addr)
909 			return (ifa);
910 	return (NULL);
911 }
912 
913 /*
914  * Process a new ARP entry
915  */
916 static void
917 process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl,
918     const struct sockaddr_in *sa)
919 {
920 	struct mibif *ifp;
921 	struct mibarp *at;
922 
923 	/* IP arp table entry */
924 	if (sdl->sdl_alen == 0) {
925 		update_arp = 1;
926 		return;
927 	}
928 	if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL)
929 		return;
930 	/* have a valid entry */
931 	if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL &&
932 	    (at = mib_arp_create(ifp, sa->sin_addr,
933 	    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
934 		return;
935 
936 	if (rtm->rtm_rmx.rmx_expire == 0)
937 		at->flags |= MIBARP_PERM;
938 	else
939 		at->flags &= ~MIBARP_PERM;
940 	at->flags |= MIBARP_FOUND;
941 }
942 
943 /*
944  * Handle a routing socket message.
945  */
946 static void
947 handle_rtmsg(struct rt_msghdr *rtm)
948 {
949 	struct sockaddr *addrs[RTAX_MAX];
950 	struct if_msghdr *ifm;
951 	struct ifa_msghdr *ifam;
952 	struct ifma_msghdr *ifmam;
953 #ifdef RTM_IFANNOUNCE
954 	struct if_announcemsghdr *ifan;
955 #endif
956 	struct mibif *ifp;
957 	struct sockaddr_dl *sdl;
958 	struct sockaddr_in *sa;
959 	struct mibifa *ifa;
960 	struct mibrcvaddr *rcv;
961 	u_char *ptr;
962 
963 	if (rtm->rtm_version != RTM_VERSION) {
964 		syslog(LOG_ERR, "Bogus RTM version %u", rtm->rtm_version);
965 		return;
966 	}
967 
968 	switch (rtm->rtm_type) {
969 
970 	  case RTM_NEWADDR:
971 		ifam = (struct ifa_msghdr *)rtm;
972 		mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs);
973 		if (addrs[RTAX_IFA] == NULL || addrs[RTAX_NETMASK] == NULL)
974 			break;
975 
976 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
977 		if ((ifa = mib_find_ifa(sa->sin_addr)) == NULL) {
978 			/* unknown address */
979 		    	if ((ifp = mib_find_if_sys(ifam->ifam_index)) == NULL) {
980 				syslog(LOG_WARNING, "RTM_NEWADDR for unknown "
981 				    "interface %u", ifam->ifam_index);
982 				break;
983 			}
984 		     	if ((ifa = alloc_ifa(ifp->index, sa->sin_addr)) == NULL)
985 				break;
986 		}
987 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_NETMASK];
988 		ifa->inmask = sa->sin_addr;
989 
990 		if (addrs[RTAX_BRD] != NULL) {
991 			sa = (struct sockaddr_in *)(void *)addrs[RTAX_BRD];
992 			ifa->inbcast = sa->sin_addr;
993 		}
994 		ifa->flags |= MIBIFA_FOUND;
995 		break;
996 
997 	  case RTM_DELADDR:
998 		ifam = (struct ifa_msghdr *)rtm;
999 		mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs);
1000 		if (addrs[RTAX_IFA] == NULL)
1001 			break;
1002 
1003 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
1004 		if ((ifa = mib_find_ifa(sa->sin_addr)) != NULL) {
1005 			ifa->flags |= MIBIFA_FOUND;
1006 			if (!(ifa->flags & MIBIFA_DESTROYED))
1007 				destroy_ifa(ifa);
1008 		}
1009 		break;
1010 
1011 	  case RTM_NEWMADDR:
1012 		ifmam = (struct ifma_msghdr *)rtm;
1013 		mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1014 		if (addrs[RTAX_IFA] == NULL ||
1015 		    addrs[RTAX_IFA]->sa_family != AF_LINK)
1016 			break;
1017 		sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1018 		if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1019 		    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) {
1020 			/* unknown address */
1021 		    	if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) {
1022 				syslog(LOG_WARNING, "RTM_NEWMADDR for unknown "
1023 				    "interface %u", sdl->sdl_index);
1024 				break;
1025 			}
1026 		     	if ((rcv = mib_rcvaddr_create(ifp,
1027 			    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
1028 				break;
1029 			rcv->flags |= MIBRCVADDR_VOLATILE;
1030 		}
1031 		rcv->flags |= MIBRCVADDR_FOUND;
1032 		break;
1033 
1034 	  case RTM_DELMADDR:
1035 		ifmam = (struct ifma_msghdr *)rtm;
1036 		mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1037 		if (addrs[RTAX_IFA] == NULL ||
1038 		    addrs[RTAX_IFA]->sa_family != AF_LINK)
1039 			break;
1040 		sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1041 		if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1042 		    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) != NULL)
1043 			mib_rcvaddr_delete(rcv);
1044 		break;
1045 
1046 	  case RTM_IFINFO:
1047 		ifm = (struct if_msghdr *)rtm;
1048 		mib_extract_addrs(ifm->ifm_addrs, (u_char *)(ifm + 1), addrs);
1049 		if ((ifp = mib_find_if_sys(ifm->ifm_index)) == NULL)
1050 			break;
1051 		if (addrs[RTAX_IFP] != NULL &&
1052 		    addrs[RTAX_IFP]->sa_family == AF_LINK) {
1053 			sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFP];
1054 			ptr = sdl->sdl_data + sdl->sdl_nlen;
1055 			get_physaddr(ifp, sdl, ptr);
1056 		}
1057 		(void)mib_fetch_ifmib(ifp);
1058 		break;
1059 
1060 #ifdef RTM_IFANNOUNCE
1061 	  case RTM_IFANNOUNCE:
1062 		ifan = (struct if_announcemsghdr *)rtm;
1063 		ifp = mib_find_if_sys(ifan->ifan_index);
1064 
1065 		switch (ifan->ifan_what) {
1066 
1067 		  case IFAN_ARRIVAL:
1068 			if (ifp == NULL && (ifp = mibif_create(ifan->ifan_index,
1069 			    ifan->ifan_name)) != NULL) {
1070 				(void)mib_fetch_ifmib(ifp);
1071 				check_llbcast(ifp);
1072 				notify_newif(ifp);
1073 			}
1074 			break;
1075 
1076 		  case IFAN_DEPARTURE:
1077 			if (ifp != NULL)
1078 				mibif_free(ifp);
1079 			break;
1080 		}
1081 		break;
1082 #endif
1083 
1084 	  case RTM_GET:
1085 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1086 		if (rtm->rtm_flags & RTF_LLINFO) {
1087 			if (addrs[RTAX_DST] == NULL ||
1088 			    addrs[RTAX_GATEWAY] == NULL ||
1089 			    addrs[RTAX_DST]->sa_family != AF_INET ||
1090 			    addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
1091 				break;
1092 			process_arp(rtm,
1093 			    (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
1094 			    (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
1095 		} else {
1096 			if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1097 				mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1098 				    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1099 		}
1100 		break;
1101 
1102 	  case RTM_ADD:
1103 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1104 		if (rtm->rtm_flags & RTF_LLINFO) {
1105 			if (addrs[RTAX_DST] == NULL ||
1106 			    addrs[RTAX_GATEWAY] == NULL ||
1107 			    addrs[RTAX_DST]->sa_family != AF_INET ||
1108 			    addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
1109 				break;
1110 			process_arp(rtm,
1111 			    (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
1112 			    (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
1113 		} else {
1114 			if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1115 				mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1116 				    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1117 		}
1118 		break;
1119 
1120 	  case RTM_DELETE:
1121 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1122 		if (rtm->rtm_errno == 0 && !(rtm->rtm_flags & RTF_LLINFO))
1123 			mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1124 			    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1125 		break;
1126 	}
1127 }
1128 
1129 /*
1130  * send a routing message
1131  */
1132 void
1133 mib_send_rtmsg(struct rt_msghdr *rtm, struct sockaddr *gw,
1134     struct sockaddr *dst, struct sockaddr *mask)
1135 {
1136 	size_t len;
1137 	struct rt_msghdr *msg;
1138 	char *cp;
1139 	ssize_t sent;
1140 
1141 	len = sizeof(*rtm) + SA_SIZE(gw) + SA_SIZE(dst) + SA_SIZE(mask);
1142 	if ((msg = malloc(len)) == NULL) {
1143 		syslog(LOG_ERR, "%s: %m", __func__);
1144 		return;
1145 	}
1146 	cp = (char *)(msg + 1);
1147 
1148 	memset(msg, 0, sizeof(*msg));
1149 	msg->rtm_flags = 0;
1150 	msg->rtm_version = RTM_VERSION;
1151 	msg->rtm_addrs = RTA_DST | RTA_GATEWAY;
1152 
1153 	memcpy(cp, dst, SA_SIZE(dst));
1154 	cp += SA_SIZE(dst);
1155 	memcpy(cp, gw, SA_SIZE(gw));
1156 	cp += SA_SIZE(gw);
1157 	if (mask != NULL) {
1158 		memcpy(cp, mask, SA_SIZE(mask));
1159 		cp += SA_SIZE(mask);
1160 		msg->rtm_addrs |= RTA_NETMASK;
1161 	}
1162 	msg->rtm_msglen = cp - (char *)msg;
1163 	msg->rtm_type = RTM_GET;
1164 	if ((sent = write(route, msg, msg->rtm_msglen)) == -1) {
1165 		syslog(LOG_ERR, "%s: write: %m", __func__);
1166 		free(msg);
1167 		return;
1168 	}
1169 	if (sent != msg->rtm_msglen) {
1170 		syslog(LOG_ERR, "%s: short write", __func__);
1171 		free(msg);
1172 		return;
1173 	}
1174 	free(msg);
1175 }
1176 
1177 /*
1178  * Fetch the routing table via sysctl
1179  */
1180 u_char *
1181 mib_fetch_rtab(int af, int info, int arg, size_t *lenp)
1182 {
1183 	int name[6];
1184 	u_char *buf, *newbuf;
1185 
1186 	name[0] = CTL_NET;
1187 	name[1] = PF_ROUTE;
1188 	name[2] = 0;
1189 	name[3] = af;
1190 	name[4] = info;
1191 	name[5] = arg;
1192 
1193 	*lenp = 0;
1194 
1195 	/* initial estimate */
1196 	if (sysctl(name, 6, NULL, lenp, NULL, 0) == -1) {
1197 		syslog(LOG_ERR, "sysctl estimate (%d,%d,%d,%d,%d,%d): %m",
1198 		    name[0], name[1], name[2], name[3], name[4], name[5]);
1199 		return (NULL);
1200 	}
1201 	if (*lenp == 0)
1202 		return (NULL);
1203 
1204 	buf = NULL;
1205 	for (;;) {
1206 		if ((newbuf = realloc(buf, *lenp)) == NULL) {
1207 			syslog(LOG_ERR, "sysctl buffer: %m");
1208 			free(buf);
1209 			return (NULL);
1210 		}
1211 		buf = newbuf;
1212 
1213 		if (sysctl(name, 6, buf, lenp, NULL, 0) == 0)
1214 			break;
1215 
1216 		if (errno != ENOMEM) {
1217 			syslog(LOG_ERR, "sysctl get: %m");
1218 			free(buf);
1219 			return (NULL);
1220 		}
1221 		*lenp += *lenp / 8 + 1;
1222 	}
1223 
1224 	return (buf);
1225 }
1226 
1227 /*
1228  * Update the following info: interface, interface addresses, interface
1229  * receive addresses, arp-table.
1230  * This does not change the interface list itself.
1231  */
1232 static void
1233 update_ifa_info(void)
1234 {
1235 	u_char *buf, *next;
1236 	struct rt_msghdr *rtm;
1237 	struct mibifa *ifa, *ifa1;
1238 	struct mibrcvaddr *rcv, *rcv1;
1239 	size_t needed;
1240 	static const int infos[][3] = {
1241 		{ 0, NET_RT_IFLIST, 0 },
1242 #ifdef NET_RT_IFMALIST
1243 		{ AF_LINK, NET_RT_IFMALIST, 0 },
1244 #endif
1245 	};
1246 	u_int i;
1247 
1248 	TAILQ_FOREACH(ifa, &mibifa_list, link)
1249 		ifa->flags &= ~MIBIFA_FOUND;
1250 	TAILQ_FOREACH(rcv, &mibrcvaddr_list, link)
1251 		rcv->flags &= ~MIBRCVADDR_FOUND;
1252 
1253 	for (i = 0; i < sizeof(infos) / sizeof(infos[0]); i++) {
1254 		if ((buf = mib_fetch_rtab(infos[i][0], infos[i][1], infos[i][2],
1255 		   &needed)) == NULL)
1256 			continue;
1257 
1258 		next = buf;
1259 		while (next < buf + needed) {
1260 			rtm = (struct rt_msghdr *)(void *)next;
1261 			next += rtm->rtm_msglen;
1262 			handle_rtmsg(rtm);
1263 		}
1264 		free(buf);
1265 	}
1266 
1267 	/*
1268 	 * Purge the address list of unused entries. These may happen for
1269 	 * interface aliases that are on the same subnet. We don't receive
1270 	 * routing socket messages for them.
1271 	 */
1272 	ifa = TAILQ_FIRST(&mibifa_list);
1273 	while (ifa != NULL) {
1274 		ifa1 = TAILQ_NEXT(ifa, link);
1275 		if (!(ifa->flags & MIBIFA_FOUND))
1276 			destroy_ifa(ifa);
1277 		ifa = ifa1;
1278 	}
1279 
1280 	rcv = TAILQ_FIRST(&mibrcvaddr_list);
1281 	while (rcv != NULL) {
1282 		rcv1 = TAILQ_NEXT(rcv, link);
1283 		if (!(rcv->flags & (MIBRCVADDR_FOUND | MIBRCVADDR_BCAST |
1284 		    MIBRCVADDR_HW)))
1285 			mib_rcvaddr_delete(rcv);
1286 		rcv = rcv1;
1287 	}
1288 }
1289 
1290 /*
1291  * Update arp table
1292  */
1293 void
1294 mib_arp_update(void)
1295 {
1296 	struct mibarp *at, *at1;
1297 	size_t needed;
1298 	u_char *buf, *next;
1299 	struct rt_msghdr *rtm;
1300 
1301 	if (in_update_arp)
1302 		return;		/* Aaargh */
1303 	in_update_arp = 1;
1304 
1305 	TAILQ_FOREACH(at, &mibarp_list, link)
1306 		at->flags &= ~MIBARP_FOUND;
1307 
1308 	if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, RTF_LLINFO, &needed)) == NULL) {
1309 		in_update_arp = 0;
1310 		return;
1311 	}
1312 
1313 	next = buf;
1314 	while (next < buf + needed) {
1315 		rtm = (struct rt_msghdr *)(void *)next;
1316 		next += rtm->rtm_msglen;
1317 		handle_rtmsg(rtm);
1318 	}
1319 	free(buf);
1320 
1321 	at = TAILQ_FIRST(&mibarp_list);
1322 	while (at != NULL) {
1323 		at1 = TAILQ_NEXT(at, link);
1324 		if (!(at->flags & MIBARP_FOUND))
1325 			mib_arp_delete(at);
1326 		at = at1;
1327 	}
1328 	mibarpticks = get_ticks();
1329 	update_arp = 0;
1330 	in_update_arp = 0;
1331 }
1332 
1333 
1334 /*
1335  * Intput on the routing socket.
1336  */
1337 static void
1338 route_input(int fd, void *udata __unused)
1339 {
1340 	u_char	buf[1024 * 16];
1341 	ssize_t n;
1342 	struct rt_msghdr *rtm;
1343 
1344 	if ((n = read(fd, buf, sizeof(buf))) == -1)
1345 		err(1, "read(rt_socket)");
1346 
1347 	if (n == 0)
1348 		errx(1, "EOF on rt_socket");
1349 
1350 	rtm = (struct rt_msghdr *)(void *)buf;
1351 	if ((size_t)n != rtm->rtm_msglen)
1352 		errx(1, "n=%zu, rtm_msglen=%u", (size_t)n, rtm->rtm_msglen);
1353 
1354 	handle_rtmsg(rtm);
1355 }
1356 
1357 /*
1358  * execute and SIOCAIFADDR
1359  */
1360 static int
1361 siocaifaddr(char *ifname, struct in_addr addr, struct in_addr mask,
1362     struct in_addr bcast)
1363 {
1364 	struct ifaliasreq addreq;
1365 	struct sockaddr_in *sa;
1366 
1367 	memset(&addreq, 0, sizeof(addreq));
1368 	strncpy(addreq.ifra_name, ifname, sizeof(addreq.ifra_name));
1369 
1370 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_addr;
1371 	sa->sin_family = AF_INET;
1372 	sa->sin_len = sizeof(*sa);
1373 	sa->sin_addr = addr;
1374 
1375 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_mask;
1376 	sa->sin_family = AF_INET;
1377 	sa->sin_len = sizeof(*sa);
1378 	sa->sin_addr = mask;
1379 
1380 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_broadaddr;
1381 	sa->sin_family = AF_INET;
1382 	sa->sin_len = sizeof(*sa);
1383 	sa->sin_addr = bcast;
1384 
1385 	return (ioctl(mib_netsock, SIOCAIFADDR, &addreq));
1386 }
1387 
1388 /*
1389  * Exececute a SIOCDIFADDR
1390  */
1391 static int
1392 siocdifaddr(const char *ifname, struct in_addr addr)
1393 {
1394 	struct ifreq delreq;
1395 	struct sockaddr_in *sa;
1396 
1397 	memset(&delreq, 0, sizeof(delreq));
1398 	strncpy(delreq.ifr_name, ifname, sizeof(delreq.ifr_name));
1399 	sa = (struct sockaddr_in *)(void *)&delreq.ifr_addr;
1400 	sa->sin_family = AF_INET;
1401 	sa->sin_len = sizeof(*sa);
1402 	sa->sin_addr = addr;
1403 
1404 	return (ioctl(mib_netsock, SIOCDIFADDR, &delreq));
1405 }
1406 
1407 /*
1408  * Verify an interface address without fetching the entire list
1409  */
1410 static int
1411 verify_ifa(const char *name, struct mibifa *ifa)
1412 {
1413 	struct ifreq req;
1414 	struct sockaddr_in *sa;
1415 
1416 	memset(&req, 0, sizeof(req));
1417 	strncpy(req.ifr_name, name, sizeof(req.ifr_name));
1418 	sa = (struct sockaddr_in *)(void *)&req.ifr_addr;
1419 	sa->sin_family = AF_INET;
1420 	sa->sin_len = sizeof(*sa);
1421 	sa->sin_addr = ifa->inaddr;
1422 
1423 	if (ioctl(mib_netsock, SIOCGIFADDR, &req) == -1)
1424 		return (-1);
1425 	if (ifa->inaddr.s_addr != sa->sin_addr.s_addr) {
1426 		syslog(LOG_ERR, "%s: address mismatch", __func__);
1427 		return (-1);
1428 	}
1429 
1430 	if (ioctl(mib_netsock, SIOCGIFNETMASK, &req) == -1)
1431 		return (-1);
1432 	if (ifa->inmask.s_addr != sa->sin_addr.s_addr) {
1433 		syslog(LOG_ERR, "%s: netmask mismatch", __func__);
1434 		return (-1);
1435 	}
1436 	return (0);
1437 }
1438 
1439 /*
1440  * Restore a deleted interface address. Don't wait for the routing socket
1441  * to update us.
1442  */
1443 void
1444 mib_undestroy_ifa(struct mibifa *ifa)
1445 {
1446 	struct mibif *ifp;
1447 
1448 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
1449 		/* keep it destroyed */
1450 		return;
1451 
1452 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast))
1453 		/* keep it destroyed */
1454 		return;
1455 
1456 	ifa->flags &= ~MIBIFA_DESTROYED;
1457 }
1458 
1459 /*
1460  * Destroy an interface address
1461  */
1462 int
1463 mib_destroy_ifa(struct mibifa *ifa)
1464 {
1465 	struct mibif *ifp;
1466 
1467 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1468 		/* ups. */
1469 		mib_iflist_bad = 1;
1470 		return (-1);
1471 	}
1472 	if (siocdifaddr(ifp->name, ifa->inaddr)) {
1473 		/* ups. */
1474 		syslog(LOG_ERR, "SIOCDIFADDR: %m");
1475 		mib_iflist_bad = 1;
1476 		return (-1);
1477 	}
1478 	ifa->flags |= MIBIFA_DESTROYED;
1479 	return (0);
1480 }
1481 
1482 /*
1483  * Rollback the modification of an address. Don't bother to wait for
1484  * the routing socket.
1485  */
1486 void
1487 mib_unmodify_ifa(struct mibifa *ifa)
1488 {
1489 	struct mibif *ifp;
1490 
1491 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1492 		/* ups. */
1493 		mib_iflist_bad = 1;
1494 		return;
1495 	}
1496 
1497 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1498 		/* ups. */
1499 		mib_iflist_bad = 1;
1500 		return;
1501 	}
1502 }
1503 
1504 /*
1505  * Modify an IFA.
1506  */
1507 int
1508 mib_modify_ifa(struct mibifa *ifa)
1509 {
1510 	struct mibif *ifp;
1511 
1512 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1513 		/* ups. */
1514 		mib_iflist_bad = 1;
1515 		return (-1);
1516 	}
1517 
1518 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1519 		/* ups. */
1520 		mib_iflist_bad = 1;
1521 		return (-1);
1522 	}
1523 
1524 	if (verify_ifa(ifp->name, ifa)) {
1525 		/* ups. */
1526 		mib_iflist_bad = 1;
1527 		return (-1);
1528 	}
1529 
1530 	return (0);
1531 }
1532 
1533 /*
1534  * Destroy a freshly created interface address. Don't bother to wait for
1535  * the routing socket.
1536  */
1537 void
1538 mib_uncreate_ifa(struct mibifa *ifa)
1539 {
1540 	struct mibif *ifp;
1541 
1542 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1543 		/* ups. */
1544 		mib_iflist_bad = 1;
1545 		return;
1546 	}
1547 	if (siocdifaddr(ifp->name, ifa->inaddr)) {
1548 		/* ups. */
1549 		mib_iflist_bad = 1;
1550 		return;
1551 	}
1552 
1553 	destroy_ifa(ifa);
1554 }
1555 
1556 /*
1557  * Create a new ifa and verify it
1558  */
1559 struct mibifa *
1560 mib_create_ifa(u_int ifindex, struct in_addr addr, struct in_addr mask,
1561     struct in_addr bcast)
1562 {
1563 	struct mibif *ifp;
1564 	struct mibifa *ifa;
1565 
1566 	if ((ifp = mib_find_if(ifindex)) == NULL)
1567 		return (NULL);
1568 	if ((ifa = alloc_ifa(ifindex, addr)) == NULL)
1569 		return (NULL);
1570 	ifa->inmask = mask;
1571 	ifa->inbcast = bcast;
1572 
1573 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1574 		syslog(LOG_ERR, "%s: %m", __func__);
1575 		destroy_ifa(ifa);
1576 		return (NULL);
1577 	}
1578 	if (verify_ifa(ifp->name, ifa)) {
1579 		destroy_ifa(ifa);
1580 		return (NULL);
1581 	}
1582 	return (ifa);
1583 }
1584 
1585 /*
1586  * Get all cloning interfaces and make them dynamic.
1587  * Hah! Whe should probably do this on a periodic basis (XXX).
1588  */
1589 static void
1590 get_cloners(void)
1591 {
1592 	struct if_clonereq req;
1593 	char *buf, *cp;
1594 	int i;
1595 
1596 	memset(&req, 0, sizeof(req));
1597 	if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1598 		syslog(LOG_ERR, "get cloners: %m");
1599 		return;
1600 	}
1601 	if ((buf = malloc(req.ifcr_total * IFNAMSIZ)) == NULL) {
1602 		syslog(LOG_ERR, "%m");
1603 		return;
1604 	}
1605 	req.ifcr_count = req.ifcr_total;
1606 	req.ifcr_buffer = buf;
1607 	if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1608 		syslog(LOG_ERR, "get cloners: %m");
1609 		free(buf);
1610 		return;
1611 	}
1612 	for (cp = buf, i = 0; i < req.ifcr_total; i++, cp += IFNAMSIZ)
1613 		mib_if_set_dyn(cp);
1614 	free(buf);
1615 }
1616 
1617 /*
1618  * Idle function
1619  */
1620 static void
1621 mibII_idle(void)
1622 {
1623 	struct mibifa *ifa;
1624 
1625 	if (mib_iflist_bad) {
1626 		TAILQ_FOREACH(ifa, &mibifa_list, link)
1627 			ifa->flags &= ~MIBIFA_DESTROYED;
1628 
1629 		/* assume, that all cloning interfaces are dynamic */
1630 		get_cloners();
1631 
1632 		mib_refresh_iflist();
1633 		update_ifa_info();
1634 		mib_arp_update();
1635 		mib_iflist_bad = 0;
1636 	}
1637 	if (update_arp)
1638 		mib_arp_update();
1639 }
1640 
1641 
1642 /*
1643  * Start the module
1644  */
1645 static void
1646 mibII_start(void)
1647 {
1648 	if ((route_fd = fd_select(route, route_input, NULL, module)) == NULL) {
1649 		syslog(LOG_ERR, "fd_select(route): %m");
1650 		return;
1651 	}
1652 	mib_refresh_iflist();
1653 	update_ifa_info();
1654 	mib_arp_update();
1655 	(void)mib_fetch_route();
1656 	mib_iftable_last_change = 0;
1657 	mib_ifstack_last_change = 0;
1658 
1659 	ifmib_reg = or_register(&oid_ifMIB,
1660 	    "The MIB module to describe generic objects for network interface"
1661 	    " sub-layers.", module);
1662 
1663 	ipmib_reg = or_register(&oid_ipMIB,
1664 	   "The MIB module for managing IP and ICMP implementations, but "
1665 	   "excluding their management of IP routes.", module);
1666 
1667 	tcpmib_reg = or_register(&oid_tcpMIB,
1668 	   "The MIB module for managing TCP implementations.", module);
1669 
1670 	udpmib_reg = or_register(&oid_udpMIB,
1671 	   "The MIB module for managing UDP implementations.", module);
1672 
1673 	ipForward_reg = or_register(&oid_ipForward,
1674 	   "The MIB module for the display of CIDR multipath IP Routes.",
1675 	   module);
1676 }
1677 
1678 /*
1679  * Initialize the module
1680  */
1681 static int
1682 mibII_init(struct lmodule *mod, int argc __unused, char *argv[] __unused)
1683 {
1684 	size_t len;
1685 
1686 	module = mod;
1687 
1688 	len = sizeof(clockinfo);
1689 	if (sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0) == -1) {
1690 		syslog(LOG_ERR, "kern.clockrate: %m");
1691 		return (-1);
1692 	}
1693 	if (len != sizeof(clockinfo)) {
1694 		syslog(LOG_ERR, "kern.clockrate: wrong size");
1695 		return (-1);
1696 	}
1697 
1698 	if ((route = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) == -1) {
1699 		syslog(LOG_ERR, "PF_ROUTE: %m");
1700 		return (-1);
1701 	}
1702 
1703 	if ((mib_netsock = socket(PF_INET, SOCK_DGRAM, 0)) == -1) {
1704 		syslog(LOG_ERR, "PF_INET: %m");
1705 		(void)close(route);
1706 		return (-1);
1707 	}
1708 	(void)shutdown(mib_netsock, SHUT_RDWR);
1709 
1710 	/* assume, that all cloning interfaces are dynamic */
1711 	get_cloners();
1712 
1713 	return (0);
1714 }
1715 
1716 static int
1717 mibII_fini(void)
1718 {
1719 	if (route_fd != NULL)
1720 		fd_deselect(route_fd);
1721 	if (route != -1)
1722 		(void)close(route);
1723 	if (mib_netsock != -1)
1724 		(void)close(mib_netsock);
1725 	/* XXX free memory */
1726 
1727 	or_unregister(ipForward_reg);
1728 	or_unregister(udpmib_reg);
1729 	or_unregister(tcpmib_reg);
1730 	or_unregister(ipmib_reg);
1731 	or_unregister(ifmib_reg);
1732 
1733 	return (0);
1734 }
1735 
1736 static void
1737 mibII_loading(const struct lmodule *mod, int loaded)
1738 {
1739 	struct mibif *ifp;
1740 
1741 	if (loaded == 1)
1742 		return;
1743 
1744 	TAILQ_FOREACH(ifp, &mibif_list, link)
1745 		if (ifp->xnotify_mod == mod) {
1746 			ifp->xnotify_mod = NULL;
1747 			ifp->xnotify_data = NULL;
1748 			ifp->xnotify = NULL;
1749 		}
1750 
1751 	mib_unregister_newif(mod);
1752 }
1753 
1754 const struct snmp_module config = {
1755 	"This module implements the interface and ip groups.",
1756 	mibII_init,
1757 	mibII_fini,
1758 	mibII_idle,	/* idle */
1759 	NULL,		/* dump */
1760 	NULL,		/* config */
1761 	mibII_start,
1762 	NULL,
1763 	mibII_ctree,
1764 	mibII_CTREE_SIZE,
1765 	mibII_loading
1766 };
1767 
1768 /*
1769  * Should have a list of these attached to each interface.
1770  */
1771 void *
1772 mibif_notify(struct mibif *ifp, const struct lmodule *mod,
1773     mibif_notify_f func, void *data)
1774 {
1775 	ifp->xnotify = func;
1776 	ifp->xnotify_data = data;
1777 	ifp->xnotify_mod = mod;
1778 
1779 	return (ifp);
1780 }
1781 
1782 void
1783 mibif_unnotify(void *arg)
1784 {
1785 	struct mibif *ifp = arg;
1786 
1787 	ifp->xnotify = NULL;
1788 	ifp->xnotify_data = NULL;
1789 	ifp->xnotify_mod = NULL;
1790 }
1791