xref: /freebsd/contrib/bsnmp/snmp_mibII/mibII.c (revision 7431dfd4580e850375fe5478d92ec770344db098)
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 /* currently fetching the arp table */
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 /* Idle poll timer */
121 static void *mibII_poll_timer;
122 
123 /* interfaces' data poll interval */
124 u_int mibII_poll_ticks;
125 
126 /* Idle poll hook */
127 static void mibII_idle(void *arg __unused);
128 
129 /*****************************/
130 
131 static const struct asn_oid oid_ifMIB = OIDX_ifMIB;
132 static const struct asn_oid oid_ipMIB = OIDX_ipMIB;
133 static const struct asn_oid oid_tcpMIB = OIDX_tcpMIB;
134 static const struct asn_oid oid_udpMIB = OIDX_udpMIB;
135 static const struct asn_oid oid_ipForward = OIDX_ipForward;
136 static const struct asn_oid oid_linkDown = OIDX_linkDown;
137 static const struct asn_oid oid_linkUp = OIDX_linkUp;
138 static const struct asn_oid oid_ifIndex = OIDX_ifIndex;
139 
140 /*****************************/
141 
142 /*
143  * Find an interface
144  */
145 struct mibif *
146 mib_find_if(u_int idx)
147 {
148 	struct mibif *ifp;
149 
150 	TAILQ_FOREACH(ifp, &mibif_list, link)
151 		if (ifp->index == idx)
152 			return (ifp);
153 	return (NULL);
154 }
155 
156 struct mibif *
157 mib_find_if_sys(u_int sysindex)
158 {
159 	struct mibif *ifp;
160 
161 	TAILQ_FOREACH(ifp, &mibif_list, link)
162 		if (ifp->sysindex == sysindex)
163 			return (ifp);
164 	return (NULL);
165 }
166 
167 struct mibif *
168 mib_find_if_name(const char *name)
169 {
170 	struct mibif *ifp;
171 
172 	TAILQ_FOREACH(ifp, &mibif_list, link)
173 		if (strcmp(ifp->name, name) == 0)
174 			return (ifp);
175 	return (NULL);
176 }
177 
178 /*
179  * Check whether an interface is dynamic. The argument may include the
180  * unit number. This assumes, that the name part does NOT contain digits.
181  */
182 int
183 mib_if_is_dyn(const char *name)
184 {
185 	size_t len;
186 	struct mibdynif *d;
187 
188 	for (len = 0; name[len] != '\0' && isalpha(name[len]) ; len++)
189 		;
190 	SLIST_FOREACH(d, &mibdynif_list, link)
191 		if (strlen(d->name) == len && strncmp(d->name, name, len) == 0)
192 			return (1);
193 	return (0);
194 }
195 
196 /* set an interface name to dynamic mode */
197 void
198 mib_if_set_dyn(const char *name)
199 {
200 	struct mibdynif *d;
201 
202 	SLIST_FOREACH(d, &mibdynif_list, link)
203 		if (strcmp(name, d->name) == 0)
204 			return;
205 	if ((d = malloc(sizeof(*d))) == NULL)
206 		err(1, NULL);
207 	strcpy(d->name, name);
208 	SLIST_INSERT_HEAD(&mibdynif_list, d, link);
209 }
210 
211 /*
212  * register for interface creations
213  */
214 int
215 mib_register_newif(int (*func)(struct mibif *), const struct lmodule *mod)
216 {
217 	struct newifreg *reg;
218 
219 	TAILQ_FOREACH(reg, &newifreg_list, link)
220 		if (reg->mod == mod) {
221 			reg->func = func;
222 			return (0);
223 		}
224 	if ((reg = malloc(sizeof(*reg))) == NULL) {
225 		syslog(LOG_ERR, "newifreg: %m");
226 		return (-1);
227 	}
228 	reg->mod = mod;
229 	reg->func = func;
230 	TAILQ_INSERT_TAIL(&newifreg_list, reg, link);
231 
232 	return (0);
233 }
234 
235 void
236 mib_unregister_newif(const struct lmodule *mod)
237 {
238 	struct newifreg *reg;
239 
240 	TAILQ_FOREACH(reg, &newifreg_list, link)
241 		if (reg->mod == mod) {
242 			TAILQ_REMOVE(&newifreg_list, reg, link);
243 			free(reg);
244 			return;
245 		}
246 
247 }
248 
249 struct mibif *
250 mib_first_if(void)
251 {
252 	return (TAILQ_FIRST(&mibif_list));
253 }
254 struct mibif *
255 mib_next_if(const struct mibif *ifp)
256 {
257 	return (TAILQ_NEXT(ifp, link));
258 }
259 
260 /*
261  * Change the admin status of an interface
262  */
263 int
264 mib_if_admin(struct mibif *ifp, int up)
265 {
266 	struct ifreq ifr;
267 
268 	strncpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
269 	if (ioctl(mib_netsock, SIOCGIFFLAGS, &ifr) == -1) {
270 		syslog(LOG_ERR, "SIOCGIFFLAGS(%s): %m", ifp->name);
271 		return (-1);
272 	}
273 	if (up)
274 		ifr.ifr_flags |= IFF_UP;
275 	else
276 		ifr.ifr_flags &= ~IFF_UP;
277 	if (ioctl(mib_netsock, SIOCSIFFLAGS, &ifr) == -1) {
278 		syslog(LOG_ERR, "SIOCSIFFLAGS(%s): %m", ifp->name);
279 		return (-1);
280 	}
281 
282 	(void)mib_fetch_ifmib(ifp);
283 
284 	return (0);
285 }
286 
287 /*
288  * Generate a link up/down trap
289  */
290 static void
291 link_trap(struct mibif *ifp, int up)
292 {
293 	struct snmp_value ifindex;
294 
295 	ifindex.var = oid_ifIndex;
296 	ifindex.var.subs[ifindex.var.len++] = ifp->index;
297 	ifindex.syntax = SNMP_SYNTAX_INTEGER;
298 	ifindex.v.integer = ifp->index;
299 
300 	snmp_send_trap(up ? &oid_linkUp : &oid_linkDown, &ifindex,
301 	    (struct snmp_value *)NULL);
302 }
303 
304 /**
305  * Fetch the GENERIC IFMIB and update the HC counters
306  */
307 static int
308 fetch_generic_mib(struct mibif *ifp, const struct ifmibdata *old)
309 {
310 	int name[6];
311 	size_t len;
312 	struct mibif_private *p = ifp->private;
313 
314 	name[0] = CTL_NET;
315 	name[1] = PF_LINK;
316 	name[2] = NETLINK_GENERIC;
317 	name[3] = IFMIB_IFDATA;
318 	name[4] = ifp->sysindex;
319 	name[5] = IFDATA_GENERAL;
320 
321 	len = sizeof(ifp->mib);
322 	if (sysctl(name, 6, &ifp->mib, &len, NULL, 0) == -1) {
323 		if (errno != ENOENT)
324 			syslog(LOG_WARNING, "sysctl(ifmib, %s) failed %m",
325 			    ifp->name);
326 		return (-1);
327 	}
328 
329 	/*
330 	 * Assume that one of the two following compounds is optimized away
331 	 */
332 	if (ULONG_MAX >= 0xffffffffffffffffULL) {
333 		p->hc_inoctets = ifp->mib.ifmd_data.ifi_ibytes;
334 		p->hc_outoctets = ifp->mib.ifmd_data.ifi_obytes;
335 		p->hc_omcasts = ifp->mib.ifmd_data.ifi_omcasts;
336 		p->hc_opackets = ifp->mib.ifmd_data.ifi_opackets;
337 		p->hc_imcasts = ifp->mib.ifmd_data.ifi_imcasts;
338 		p->hc_ipackets = ifp->mib.ifmd_data.ifi_ipackets;
339 
340 	} else if (ULONG_MAX >= 0xffffffff) {
341 
342 #define	UPDATE(HC, MIB)							\
343 		if (old->ifmd_data.MIB > ifp->mib.ifmd_data.MIB)	\
344 			p->HC += (0x100000000ULL +			\
345 			    ifp->mib.ifmd_data.MIB) -			\
346 			    old->ifmd_data.MIB;				\
347 		else							\
348 			p->HC += ifp->mib.ifmd_data.MIB -		\
349 			    old->ifmd_data.MIB;
350 
351 		UPDATE(hc_inoctets, ifi_ibytes)
352 		UPDATE(hc_outoctets, ifi_obytes)
353 		UPDATE(hc_omcasts, ifi_omcasts)
354 		UPDATE(hc_opackets, ifi_opackets)
355 		UPDATE(hc_imcasts, ifi_imcasts)
356 		UPDATE(hc_ipackets, ifi_ipackets)
357 
358 #undef	UPDATE
359 	} else
360 		abort();
361 	return (0);
362 }
363 
364 /**
365  * Update the 64-bit interface counters
366  */
367 static void
368 update_hc_counters(void *arg __unused)
369 {
370 	struct mibif *ifp;
371 	struct ifmibdata oldmib;
372 
373 	TAILQ_FOREACH(ifp, &mibif_list, link) {
374 		oldmib = ifp->mib;
375 		(void)fetch_generic_mib(ifp, &oldmib);
376 	}
377 }
378 
379 /**
380  * Recompute the poll timer for the HC counters
381  */
382 void
383 mibif_reset_hc_timer(void)
384 {
385 	u_int ticks;
386 
387 	if ((ticks = mibif_force_hc_update_interval) == 0) {
388 		if (mibif_maxspeed <= IF_Mbps(10)) {
389 			/* at 10Mbps overflow needs 3436 seconds */
390 			ticks = 3000 * 100;	/* 50 minutes */
391 		} else if (mibif_maxspeed <= IF_Mbps(100)) {
392 			/* at 100Mbps overflow needs 343 seconds */
393 			ticks = 300 * 100;	/* 5 minutes */
394 		} else if (mibif_maxspeed < IF_Mbps(622)) {
395 			/* at 622Mbps overflow needs 53 seconds */
396 			ticks = 40 * 100;	/* 40 seconds */
397 		} else if (mibif_maxspeed <= IF_Mbps(1000)) {
398 			/* at 1Gbps overflow needs  34 seconds */
399 			ticks = 20 * 100;	/* 20 seconds */
400 		} else {
401 			/* at 10Gbps overflow needs 3.4 seconds */
402 			ticks = 100;		/* 1 seconds */
403 		}
404 	}
405 
406 	if (ticks == mibif_hc_update_interval)
407 		return;
408 
409 	if (hc_update_timer != NULL) {
410 		timer_stop(hc_update_timer);
411 		hc_update_timer = NULL;
412 	}
413 	update_hc_counters(NULL);
414 	if ((hc_update_timer = timer_start_repeat(ticks * 10, ticks * 10,
415 	    update_hc_counters, NULL, module)) == NULL) {
416 		syslog(LOG_ERR, "timer_start(%u): %m", ticks);
417 		return;
418 	}
419 	mibif_hc_update_interval = ticks;
420 }
421 
422 /**
423  * Restart the idle poll timer.
424  */
425 void
426 mibif_restart_mibII_poll_timer(void)
427 {
428 	if (mibII_poll_timer != NULL)
429 		timer_stop(mibII_poll_timer);
430 
431 	if ((mibII_poll_timer = timer_start_repeat(mibII_poll_ticks * 10,
432 	    mibII_poll_ticks * 10, mibII_idle, NULL, module)) == NULL)
433 		syslog(LOG_ERR, "timer_start(%u): %m", mibII_poll_ticks);
434 }
435 
436 /*
437  * Fetch new MIB data.
438  */
439 int
440 mib_fetch_ifmib(struct mibif *ifp)
441 {
442 	int name[6];
443 	size_t len;
444 	void *newmib;
445 	struct ifmibdata oldmib = ifp->mib;
446 
447 	if (fetch_generic_mib(ifp, &oldmib) == -1)
448 		return (-1);
449 
450 	/*
451 	 * Quoting RFC2863, 3.1.15: "... LinkUp and linkDown traps are
452 	 * generated just after ifOperStatus leaves, or just before it
453 	 * enters, the down state, respectively;"
454 	 */
455 	if (ifp->trap_enable && ifp->mib.ifmd_data.ifi_link_state !=
456 	    oldmib.ifmd_data.ifi_link_state &&
457 	    (ifp->mib.ifmd_data.ifi_link_state == LINK_STATE_DOWN ||
458 	    oldmib.ifmd_data.ifi_link_state == LINK_STATE_DOWN))
459 		link_trap(ifp, ifp->mib.ifmd_data.ifi_link_state ==
460 		    LINK_STATE_UP ? 1 : 0);
461 
462 	ifp->flags &= ~(MIBIF_HIGHSPEED | MIBIF_VERYHIGHSPEED);
463 	if (ifp->mib.ifmd_data.ifi_baudrate > 20000000) {
464 		ifp->flags |= MIBIF_HIGHSPEED;
465 		if (ifp->mib.ifmd_data.ifi_baudrate > 650000000)
466 			ifp->flags |= MIBIF_VERYHIGHSPEED;
467 	}
468 	if (ifp->mib.ifmd_data.ifi_baudrate > mibif_maxspeed) {
469 		mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
470 		mibif_reset_hc_timer();
471 	}
472 
473 	/*
474 	 * linkspecific MIB
475 	 */
476 	name[0] = CTL_NET;
477 	name[1] = PF_LINK;
478 	name[2] = NETLINK_GENERIC;
479 	name[3] = IFMIB_IFDATA;
480 	name[4] = ifp->sysindex;
481 	name[5] = IFDATA_LINKSPECIFIC;
482 	if (sysctl(name, 6, NULL, &len, NULL, 0) == -1) {
483 		syslog(LOG_WARNING, "sysctl linkmib estimate (%s): %m",
484 		    ifp->name);
485 		if (ifp->specmib != NULL) {
486 			ifp->specmib = NULL;
487 			ifp->specmiblen = 0;
488 		}
489 		goto out;
490 	}
491 	if (len == 0) {
492 		if (ifp->specmib != NULL) {
493 			ifp->specmib = NULL;
494 			ifp->specmiblen = 0;
495 		}
496 		goto out;
497 	}
498 
499 	if (ifp->specmiblen != len) {
500 		if ((newmib = realloc(ifp->specmib, len)) == NULL) {
501 			ifp->specmib = NULL;
502 			ifp->specmiblen = 0;
503 			goto out;
504 		}
505 		ifp->specmib = newmib;
506 		ifp->specmiblen = len;
507 	}
508 	if (sysctl(name, 6, ifp->specmib, &len, NULL, 0) == -1) {
509 		syslog(LOG_WARNING, "sysctl linkmib (%s): %m", ifp->name);
510 		if (ifp->specmib != NULL) {
511 			ifp->specmib = NULL;
512 			ifp->specmiblen = 0;
513 		}
514 	}
515 
516   out:
517 	ifp->mibtick = get_ticks();
518 	return (0);
519 }
520 
521 /* find first/next address for a given interface */
522 struct mibifa *
523 mib_first_ififa(const struct mibif *ifp)
524 {
525 	struct mibifa *ifa;
526 
527 	TAILQ_FOREACH(ifa, &mibifa_list, link)
528 		if (ifp->index == ifa->ifindex)
529 			return (ifa);
530 	return (NULL);
531 }
532 
533 struct mibifa *
534 mib_next_ififa(struct mibifa *ifa0)
535 {
536 	struct mibifa *ifa;
537 
538 	ifa = ifa0;
539 	while ((ifa = TAILQ_NEXT(ifa, link)) != NULL)
540 		if (ifa->ifindex == ifa0->ifindex)
541 			return (ifa);
542 	return (NULL);
543 }
544 
545 /*
546  * Allocate a new IFA
547  */
548 static struct mibifa *
549 alloc_ifa(u_int ifindex, struct in_addr addr)
550 {
551 	struct mibifa *ifa;
552 	uint32_t ha;
553 
554 	if ((ifa = malloc(sizeof(struct mibifa))) == NULL) {
555 		syslog(LOG_ERR, "ifa: %m");
556 		return (NULL);
557 	}
558 	ifa->inaddr = addr;
559 	ifa->ifindex = ifindex;
560 
561 	ha = ntohl(ifa->inaddr.s_addr);
562 	ifa->index.len = 4;
563 	ifa->index.subs[0] = (ha >> 24) & 0xff;
564 	ifa->index.subs[1] = (ha >> 16) & 0xff;
565 	ifa->index.subs[2] = (ha >>  8) & 0xff;
566 	ifa->index.subs[3] = (ha >>  0) & 0xff;
567 
568 	ifa->flags = 0;
569 	ifa->inbcast.s_addr = 0;
570 	ifa->inmask.s_addr = 0xffffffff;
571 
572 	INSERT_OBJECT_OID(ifa, &mibifa_list);
573 
574 	return (ifa);
575 }
576 
577 /*
578  * Delete an interface address
579  */
580 static void
581 destroy_ifa(struct mibifa *ifa)
582 {
583 	TAILQ_REMOVE(&mibifa_list, ifa, link);
584 	free(ifa);
585 }
586 
587 
588 /*
589  * Helper routine to extract the sockaddr structures from a routing
590  * socket message.
591  */
592 void
593 mib_extract_addrs(int addrs, u_char *info, struct sockaddr **out)
594 {
595 	u_int i;
596 
597 	for (i = 0; i < RTAX_MAX; i++) {
598 		if ((addrs & (1 << i)) != 0) {
599 			*out = (struct sockaddr *)(void *)info;
600 			info += roundup((*out)->sa_len, sizeof(long));
601 		} else
602 			*out = NULL;
603 		out++;
604 	}
605 }
606 
607 /*
608  * save the phys address of an interface. Handle receive address entries here.
609  */
610 static void
611 get_physaddr(struct mibif *ifp, struct sockaddr_dl *sdl, u_char *ptr)
612 {
613 	u_char *np;
614 	struct mibrcvaddr *rcv;
615 
616 	if (sdl->sdl_alen == 0) {
617 		/* no address */
618 		if (ifp->physaddrlen != 0) {
619 			if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
620 			    ifp->physaddrlen)) != NULL)
621 				mib_rcvaddr_delete(rcv);
622 			free(ifp->physaddr);
623 			ifp->physaddr = NULL;
624 			ifp->physaddrlen = 0;
625 		}
626 		return;
627 	}
628 
629 	if (ifp->physaddrlen != sdl->sdl_alen) {
630 		/* length changed */
631 		if (ifp->physaddrlen) {
632 			/* delete olf receive address */
633 			if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
634 			    ifp->physaddrlen)) != NULL)
635 				mib_rcvaddr_delete(rcv);
636 		}
637 		if ((np = realloc(ifp->physaddr, sdl->sdl_alen)) == NULL) {
638 			free(ifp->physaddr);
639 			ifp->physaddr = NULL;
640 			ifp->physaddrlen = 0;
641 			return;
642 		}
643 		ifp->physaddr = np;
644 		ifp->physaddrlen = sdl->sdl_alen;
645 
646 	} else if (memcmp(ifp->physaddr, ptr, ifp->physaddrlen) == 0) {
647 		/* no change */
648 		return;
649 
650 	} else {
651 		/* address changed */
652 
653 		/* delete olf receive address */
654 		if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
655 		    ifp->physaddrlen)) != NULL)
656 			mib_rcvaddr_delete(rcv);
657 	}
658 
659 	memcpy(ifp->physaddr, ptr, ifp->physaddrlen);
660 
661 	/* make new receive address */
662 	if ((rcv = mib_rcvaddr_create(ifp, ifp->physaddr, ifp->physaddrlen)) != NULL)
663 		rcv->flags |= MIBRCVADDR_HW;
664 }
665 
666 /*
667  * Free an interface
668  */
669 static void
670 mibif_free(struct mibif *ifp)
671 {
672 	struct mibif *ifp1;
673 	struct mibindexmap *map;
674 	struct mibifa *ifa, *ifa1;
675 	struct mibrcvaddr *rcv, *rcv1;
676 	struct mibarp *at, *at1;
677 
678 	if (ifp->xnotify != NULL)
679 		(*ifp->xnotify)(ifp, MIBIF_NOTIFY_DESTROY, ifp->xnotify_data);
680 
681 	(void)mib_ifstack_delete(ifp, NULL);
682 	(void)mib_ifstack_delete(NULL, ifp);
683 
684 	TAILQ_REMOVE(&mibif_list, ifp, link);
685 
686 	/* if this was the fastest interface - recompute this */
687 	if (ifp->mib.ifmd_data.ifi_baudrate == mibif_maxspeed) {
688 		mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
689 		TAILQ_FOREACH(ifp1, &mibif_list, link)
690 			if (ifp1->mib.ifmd_data.ifi_baudrate > mibif_maxspeed)
691 				mibif_maxspeed =
692 				    ifp1->mib.ifmd_data.ifi_baudrate;
693 		mibif_reset_hc_timer();
694 	}
695 
696 	free(ifp->private);
697 	if (ifp->physaddr != NULL)
698 		free(ifp->physaddr);
699 	if (ifp->specmib != NULL)
700 		free(ifp->specmib);
701 
702 	STAILQ_FOREACH(map, &mibindexmap_list, link)
703 		if (map->mibif == ifp) {
704 			map->mibif = NULL;
705 			break;
706 		}
707 
708 	/* purge interface addresses */
709 	ifa = TAILQ_FIRST(&mibifa_list);
710 	while (ifa != NULL) {
711 		ifa1 = TAILQ_NEXT(ifa, link);
712 		if (ifa->ifindex == ifp->index)
713 			destroy_ifa(ifa);
714 		ifa = ifa1;
715 	}
716 
717 	/* purge receive addresses */
718 	rcv = TAILQ_FIRST(&mibrcvaddr_list);
719 	while (rcv != NULL) {
720 		rcv1 = TAILQ_NEXT(rcv, link);
721 		if (rcv->ifindex == ifp->index)
722 			mib_rcvaddr_delete(rcv);
723 		rcv = rcv1;
724 	}
725 
726 	/* purge ARP entries */
727 	at = TAILQ_FIRST(&mibarp_list);
728 	while (at != NULL) {
729 		at1 = TAILQ_NEXT(at, link);
730 		if (at->index.subs[0] == ifp->index)
731 			mib_arp_delete(at);
732 		at = at1;
733 	}
734 
735 
736 	free(ifp);
737 	mib_if_number--;
738 	mib_iftable_last_change = this_tick;
739 }
740 
741 /*
742  * Create a new interface
743  */
744 static struct mibif *
745 mibif_create(u_int sysindex, const char *name)
746 {
747 	struct mibif *ifp;
748 	struct mibindexmap *map;
749 
750 	if ((ifp = malloc(sizeof(*ifp))) == NULL) {
751 		syslog(LOG_WARNING, "%s: %m", __func__);
752 		return (NULL);
753 	}
754 	memset(ifp, 0, sizeof(*ifp));
755 	if ((ifp->private = malloc(sizeof(struct mibif_private))) == NULL) {
756 		syslog(LOG_WARNING, "%s: %m", __func__);
757 		free(ifp);
758 		return (NULL);
759 	}
760 	memset(ifp->private, 0, sizeof(struct mibif_private));
761 
762 	ifp->sysindex = sysindex;
763 	strcpy(ifp->name, name);
764 	strcpy(ifp->descr, name);
765 	ifp->spec_oid = oid_zeroDotZero;
766 
767 	map = NULL;
768 	if (!mib_if_is_dyn(ifp->name)) {
769 		/* non-dynamic. look whether we know the interface */
770 		STAILQ_FOREACH(map, &mibindexmap_list, link)
771 			if (strcmp(map->name, ifp->name) == 0) {
772 				ifp->index = map->ifindex;
773 				map->mibif = ifp;
774 				break;
775 			}
776 		/* assume it has a connector if it is not dynamic */
777 		ifp->has_connector = 1;
778 		ifp->trap_enable = 1;
779 	}
780 	if (map == NULL) {
781 		/* new interface - get new index */
782 		if (next_if_index > 0x7fffffff)
783 			errx(1, "ifindex wrap");
784 
785 		if ((map = malloc(sizeof(*map))) == NULL) {
786 			syslog(LOG_ERR, "ifmap: %m");
787 			free(ifp);
788 			return (NULL);
789 		}
790 		map->ifindex = next_if_index++;
791 		map->sysindex = ifp->sysindex;
792 		strcpy(map->name, ifp->name);
793 		map->mibif = ifp;
794 		STAILQ_INSERT_TAIL(&mibindexmap_list, map, link);
795 	} else {
796 		/* re-instantiate. Introduce a counter discontinuity */
797 		ifp->counter_disc = get_ticks();
798 	}
799 	ifp->index = map->ifindex;
800 	ifp->mib.ifmd_data.ifi_link_state = LINK_STATE_UNKNOWN;
801 
802 	INSERT_OBJECT_INT(ifp, &mibif_list);
803 	mib_if_number++;
804 	mib_iftable_last_change = this_tick;
805 
806 	/* instantiate default ifStack entries */
807 	(void)mib_ifstack_create(ifp, NULL);
808 	(void)mib_ifstack_create(NULL, ifp);
809 
810 	return (ifp);
811 }
812 
813 /*
814  * Inform all interested parties about a new interface
815  */
816 static void
817 notify_newif(struct mibif *ifp)
818 {
819 	struct newifreg *reg;
820 
821 	TAILQ_FOREACH(reg, &newifreg_list, link)
822 		if ((*reg->func)(ifp))
823 			return;
824 }
825 
826 /*
827  * This is called for new interfaces after we have fetched the interface
828  * MIB. If this is a broadcast interface try to guess the broadcast address
829  * depending on the interface type.
830  */
831 static void
832 check_llbcast(struct mibif *ifp)
833 {
834 	static u_char ether_bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
835 	static u_char arcnet_bcast = 0;
836 	struct mibrcvaddr *rcv;
837 
838 	if (!(ifp->mib.ifmd_flags & IFF_BROADCAST))
839 		return;
840 
841 	switch (ifp->mib.ifmd_data.ifi_type) {
842 
843 	  case IFT_ETHER:
844 	  case IFT_FDDI:
845 	  case IFT_ISO88025:
846 	  case IFT_L2VLAN:
847 		if (mib_find_rcvaddr(ifp->index, ether_bcast, 6) == NULL &&
848 		    (rcv = mib_rcvaddr_create(ifp, ether_bcast, 6)) != NULL)
849 			rcv->flags |= MIBRCVADDR_BCAST;
850 		break;
851 
852 	  case IFT_ARCNET:
853 		if (mib_find_rcvaddr(ifp->index, &arcnet_bcast, 1) == NULL &&
854 		    (rcv = mib_rcvaddr_create(ifp, &arcnet_bcast, 1)) != NULL)
855 			rcv->flags |= MIBRCVADDR_BCAST;
856 		break;
857 	}
858 }
859 
860 
861 /*
862  * Retrieve the current interface list from the system.
863  */
864 void
865 mib_refresh_iflist(void)
866 {
867 	struct mibif *ifp, *ifp1;
868 	size_t len;
869 	u_short idx;
870 	int name[6];
871 	int count;
872 	struct ifmibdata mib;
873 
874 	TAILQ_FOREACH(ifp, &mibif_list, link)
875 		ifp->flags &= ~MIBIF_FOUND;
876 
877 	len = sizeof(count);
878 	if (sysctlbyname("net.link.generic.system.ifcount", &count, &len,
879 	    NULL, 0) == -1) {
880 		syslog(LOG_ERR, "ifcount: %m");
881 		return;
882 	}
883 	name[0] = CTL_NET;
884 	name[1] = PF_LINK;
885 	name[2] = NETLINK_GENERIC;
886 	name[3] = IFMIB_IFDATA;
887 	name[5] = IFDATA_GENERAL;
888 	for (idx = 1; idx <= count; idx++) {
889 		name[4] = idx;
890 		len = sizeof(mib);
891 		if (sysctl(name, 6, &mib, &len, NULL, 0) == -1) {
892 			if (errno == ENOENT)
893 				continue;
894 			syslog(LOG_ERR, "ifmib(%u): %m", idx);
895 			return;
896 		}
897 		if ((ifp = mib_find_if_sys(idx)) != NULL) {
898 			ifp->flags |= MIBIF_FOUND;
899 			continue;
900 		}
901 		/* Unknown interface - create */
902 		if ((ifp = mibif_create(idx, mib.ifmd_name)) != NULL) {
903 			ifp->flags |= MIBIF_FOUND;
904 			(void)mib_fetch_ifmib(ifp);
905 			check_llbcast(ifp);
906 			notify_newif(ifp);
907 		}
908 	}
909 
910 	/*
911 	 * Purge interfaces that disappeared
912 	 */
913 	ifp = TAILQ_FIRST(&mibif_list);
914 	while (ifp != NULL) {
915 		ifp1 = TAILQ_NEXT(ifp, link);
916 		if (!(ifp->flags & MIBIF_FOUND))
917 			mibif_free(ifp);
918 		ifp = ifp1;
919 	}
920 }
921 
922 /*
923  * Find an interface address
924  */
925 struct mibifa *
926 mib_find_ifa(struct in_addr addr)
927 {
928 	struct mibifa *ifa;
929 
930 	TAILQ_FOREACH(ifa, &mibifa_list, link)
931 		if (ifa->inaddr.s_addr == addr.s_addr)
932 			return (ifa);
933 	return (NULL);
934 }
935 
936 /*
937  * Process a new ARP entry
938  */
939 static void
940 process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl,
941     const struct sockaddr_in *sa)
942 {
943 	struct mibif *ifp;
944 	struct mibarp *at;
945 
946 	/* IP arp table entry */
947 	if (sdl->sdl_alen == 0)
948 		return;
949 	if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL)
950 		return;
951 	/* have a valid entry */
952 	if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL &&
953 	    (at = mib_arp_create(ifp, sa->sin_addr,
954 	    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
955 		return;
956 
957 	if (rtm->rtm_rmx.rmx_expire == 0)
958 		at->flags |= MIBARP_PERM;
959 	else
960 		at->flags &= ~MIBARP_PERM;
961 	at->flags |= MIBARP_FOUND;
962 }
963 
964 /*
965  * Handle a routing socket message.
966  */
967 static void
968 handle_rtmsg(struct rt_msghdr *rtm)
969 {
970 	struct sockaddr *addrs[RTAX_MAX];
971 	struct if_msghdr *ifm;
972 	struct ifa_msghdr ifam;
973 	struct ifma_msghdr *ifmam;
974 #ifdef RTM_IFANNOUNCE
975 	struct if_announcemsghdr *ifan;
976 #endif
977 	struct mibif *ifp;
978 	struct sockaddr_dl *sdl;
979 	struct sockaddr_in *sa;
980 	struct mibifa *ifa;
981 	struct mibrcvaddr *rcv;
982 	u_char *ptr;
983 
984 	if (rtm->rtm_version != RTM_VERSION) {
985 		syslog(LOG_ERR, "Bogus RTM version %u", rtm->rtm_version);
986 		return;
987 	}
988 
989 	switch (rtm->rtm_type) {
990 
991 	  case RTM_NEWADDR:
992 		memcpy(&ifam, rtm, sizeof(ifam));
993 		mib_extract_addrs(ifam.ifam_addrs, (u_char *)(&ifam + 1), addrs);
994 		if (addrs[RTAX_IFA] == NULL || addrs[RTAX_NETMASK] == NULL)
995 			break;
996 
997 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
998 		if ((ifa = mib_find_ifa(sa->sin_addr)) == NULL) {
999 			/* unknown address */
1000 		    	if ((ifp = mib_find_if_sys(ifam.ifam_index)) == NULL) {
1001 				syslog(LOG_WARNING, "RTM_NEWADDR for unknown "
1002 				    "interface %u", ifam.ifam_index);
1003 				break;
1004 			}
1005 		     	if ((ifa = alloc_ifa(ifp->index, sa->sin_addr)) == NULL)
1006 				break;
1007 		}
1008 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_NETMASK];
1009 		ifa->inmask = sa->sin_addr;
1010 
1011 		if (addrs[RTAX_BRD] != NULL) {
1012 			sa = (struct sockaddr_in *)(void *)addrs[RTAX_BRD];
1013 			ifa->inbcast = sa->sin_addr;
1014 		}
1015 		ifa->flags |= MIBIFA_FOUND;
1016 		break;
1017 
1018 	  case RTM_DELADDR:
1019 		memcpy(&ifam, rtm, sizeof(ifam));
1020 		mib_extract_addrs(ifam.ifam_addrs, (u_char *)(&ifam + 1), addrs);
1021 		if (addrs[RTAX_IFA] == NULL)
1022 			break;
1023 
1024 		sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
1025 		if ((ifa = mib_find_ifa(sa->sin_addr)) != NULL) {
1026 			ifa->flags |= MIBIFA_FOUND;
1027 			if (!(ifa->flags & MIBIFA_DESTROYED))
1028 				destroy_ifa(ifa);
1029 		}
1030 		break;
1031 
1032 	  case RTM_NEWMADDR:
1033 		ifmam = (struct ifma_msghdr *)rtm;
1034 		mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1035 		if (addrs[RTAX_IFA] == NULL ||
1036 		    addrs[RTAX_IFA]->sa_family != AF_LINK)
1037 			break;
1038 		sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1039 		if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1040 		    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) {
1041 			/* unknown address */
1042 		    	if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) {
1043 				syslog(LOG_WARNING, "RTM_NEWMADDR for unknown "
1044 				    "interface %u", sdl->sdl_index);
1045 				break;
1046 			}
1047 		     	if ((rcv = mib_rcvaddr_create(ifp,
1048 			    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
1049 				break;
1050 			rcv->flags |= MIBRCVADDR_VOLATILE;
1051 		}
1052 		rcv->flags |= MIBRCVADDR_FOUND;
1053 		break;
1054 
1055 	  case RTM_DELMADDR:
1056 		ifmam = (struct ifma_msghdr *)rtm;
1057 		mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1058 		if (addrs[RTAX_IFA] == NULL ||
1059 		    addrs[RTAX_IFA]->sa_family != AF_LINK)
1060 			break;
1061 		sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1062 		if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1063 		    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) != NULL)
1064 			mib_rcvaddr_delete(rcv);
1065 		break;
1066 
1067 	  case RTM_IFINFO:
1068 		ifm = (struct if_msghdr *)(void *)rtm;
1069 		mib_extract_addrs(ifm->ifm_addrs, (u_char *)(ifm + 1), addrs);
1070 		if ((ifp = mib_find_if_sys(ifm->ifm_index)) == NULL)
1071 			break;
1072 		if (addrs[RTAX_IFP] != NULL &&
1073 		    addrs[RTAX_IFP]->sa_family == AF_LINK) {
1074 			sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFP];
1075 			ptr = sdl->sdl_data + sdl->sdl_nlen;
1076 			get_physaddr(ifp, sdl, ptr);
1077 		}
1078 		(void)mib_fetch_ifmib(ifp);
1079 		break;
1080 
1081 #ifdef RTM_IFANNOUNCE
1082 	  case RTM_IFANNOUNCE:
1083 		ifan = (struct if_announcemsghdr *)rtm;
1084 		ifp = mib_find_if_sys(ifan->ifan_index);
1085 
1086 		switch (ifan->ifan_what) {
1087 
1088 		  case IFAN_ARRIVAL:
1089 			if (ifp == NULL && (ifp = mibif_create(ifan->ifan_index,
1090 			    ifan->ifan_name)) != NULL) {
1091 				(void)mib_fetch_ifmib(ifp);
1092 				check_llbcast(ifp);
1093 				notify_newif(ifp);
1094 			}
1095 			break;
1096 
1097 		  case IFAN_DEPARTURE:
1098 			if (ifp != NULL)
1099 				mibif_free(ifp);
1100 			break;
1101 		}
1102 		break;
1103 #endif
1104 	  case RTM_GET:
1105 	  case RTM_ADD:
1106 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1107 		if (rtm->rtm_flags & RTF_LLINFO) {
1108 			if (addrs[RTAX_DST] == NULL ||
1109 			    addrs[RTAX_GATEWAY] == NULL ||
1110 			    addrs[RTAX_DST]->sa_family != AF_INET ||
1111 			    addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
1112 				break;
1113 			process_arp(rtm,
1114 			    (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
1115 			    (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
1116 		} else {
1117 			if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1118 				mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1119 				    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1120 		}
1121 		break;
1122 
1123 	  case RTM_DELETE:
1124 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1125 
1126 		if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1127 			mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1128 			    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1129 		break;
1130 	}
1131 }
1132 
1133 /*
1134  * send a routing message
1135  */
1136 void
1137 mib_send_rtmsg(struct rt_msghdr *rtm, struct sockaddr *gw,
1138     struct sockaddr *dst, struct sockaddr *mask)
1139 {
1140 	size_t len;
1141 	struct rt_msghdr *msg;
1142 	char *cp;
1143 	ssize_t sent;
1144 
1145 	len = sizeof(*rtm) + SA_SIZE(gw) + SA_SIZE(dst) + SA_SIZE(mask);
1146 	if ((msg = malloc(len)) == NULL) {
1147 		syslog(LOG_ERR, "%s: %m", __func__);
1148 		return;
1149 	}
1150 	cp = (char *)(msg + 1);
1151 
1152 	memset(msg, 0, sizeof(*msg));
1153 	msg->rtm_flags = 0;
1154 	msg->rtm_version = RTM_VERSION;
1155 	msg->rtm_addrs = RTA_DST | RTA_GATEWAY;
1156 
1157 	memcpy(cp, dst, SA_SIZE(dst));
1158 	cp += SA_SIZE(dst);
1159 	memcpy(cp, gw, SA_SIZE(gw));
1160 	cp += SA_SIZE(gw);
1161 	if (mask != NULL) {
1162 		memcpy(cp, mask, SA_SIZE(mask));
1163 		cp += SA_SIZE(mask);
1164 		msg->rtm_addrs |= RTA_NETMASK;
1165 	}
1166 	msg->rtm_msglen = cp - (char *)msg;
1167 	msg->rtm_type = RTM_GET;
1168 	if ((sent = write(route, msg, msg->rtm_msglen)) == -1) {
1169 		syslog(LOG_ERR, "%s: write: %m", __func__);
1170 		free(msg);
1171 		return;
1172 	}
1173 	if (sent != msg->rtm_msglen) {
1174 		syslog(LOG_ERR, "%s: short write", __func__);
1175 		free(msg);
1176 		return;
1177 	}
1178 	free(msg);
1179 }
1180 
1181 /*
1182  * Fetch the routing table via sysctl
1183  */
1184 u_char *
1185 mib_fetch_rtab(int af, int info, int arg, size_t *lenp)
1186 {
1187 	int name[6];
1188 	u_char *buf, *newbuf;
1189 
1190 	name[0] = CTL_NET;
1191 	name[1] = PF_ROUTE;
1192 	name[2] = 0;
1193 	name[3] = af;
1194 	name[4] = info;
1195 	name[5] = arg;
1196 
1197 	*lenp = 0;
1198 
1199 	/* initial estimate */
1200 	if (sysctl(name, 6, NULL, lenp, NULL, 0) == -1) {
1201 		syslog(LOG_ERR, "sysctl estimate (%d,%d,%d,%d,%d,%d): %m",
1202 		    name[0], name[1], name[2], name[3], name[4], name[5]);
1203 		return (NULL);
1204 	}
1205 	if (*lenp == 0)
1206 		return (NULL);
1207 
1208 	buf = NULL;
1209 	for (;;) {
1210 		if ((newbuf = realloc(buf, *lenp)) == NULL) {
1211 			syslog(LOG_ERR, "sysctl buffer: %m");
1212 			free(buf);
1213 			return (NULL);
1214 		}
1215 		buf = newbuf;
1216 
1217 		if (sysctl(name, 6, buf, lenp, NULL, 0) == 0)
1218 			break;
1219 
1220 		if (errno != ENOMEM) {
1221 			syslog(LOG_ERR, "sysctl get: %m");
1222 			free(buf);
1223 			return (NULL);
1224 		}
1225 		*lenp += *lenp / 8 + 1;
1226 	}
1227 
1228 	return (buf);
1229 }
1230 
1231 /*
1232  * Update the following info: interface, interface addresses, interface
1233  * receive addresses, arp-table.
1234  * This does not change the interface list itself.
1235  */
1236 static void
1237 update_ifa_info(void)
1238 {
1239 	u_char *buf, *next;
1240 	struct rt_msghdr *rtm;
1241 	struct mibifa *ifa, *ifa1;
1242 	struct mibrcvaddr *rcv, *rcv1;
1243 	size_t needed;
1244 	static const int infos[][3] = {
1245 		{ 0, NET_RT_IFLIST, 0 },
1246 #ifdef NET_RT_IFMALIST
1247 		{ AF_LINK, NET_RT_IFMALIST, 0 },
1248 #endif
1249 	};
1250 	u_int i;
1251 
1252 	TAILQ_FOREACH(ifa, &mibifa_list, link)
1253 		ifa->flags &= ~MIBIFA_FOUND;
1254 	TAILQ_FOREACH(rcv, &mibrcvaddr_list, link)
1255 		rcv->flags &= ~MIBRCVADDR_FOUND;
1256 
1257 	for (i = 0; i < sizeof(infos) / sizeof(infos[0]); i++) {
1258 		if ((buf = mib_fetch_rtab(infos[i][0], infos[i][1], infos[i][2],
1259 		   &needed)) == NULL)
1260 			continue;
1261 
1262 		next = buf;
1263 		while (next < buf + needed) {
1264 			rtm = (struct rt_msghdr *)(void *)next;
1265 			next += rtm->rtm_msglen;
1266 			handle_rtmsg(rtm);
1267 		}
1268 		free(buf);
1269 	}
1270 
1271 	/*
1272 	 * Purge the address list of unused entries. These may happen for
1273 	 * interface aliases that are on the same subnet. We don't receive
1274 	 * routing socket messages for them.
1275 	 */
1276 	ifa = TAILQ_FIRST(&mibifa_list);
1277 	while (ifa != NULL) {
1278 		ifa1 = TAILQ_NEXT(ifa, link);
1279 		if (!(ifa->flags & MIBIFA_FOUND))
1280 			destroy_ifa(ifa);
1281 		ifa = ifa1;
1282 	}
1283 
1284 	rcv = TAILQ_FIRST(&mibrcvaddr_list);
1285 	while (rcv != NULL) {
1286 		rcv1 = TAILQ_NEXT(rcv, link);
1287 		if (!(rcv->flags & (MIBRCVADDR_FOUND | MIBRCVADDR_BCAST |
1288 		    MIBRCVADDR_HW)))
1289 			mib_rcvaddr_delete(rcv);
1290 		rcv = rcv1;
1291 	}
1292 }
1293 
1294 /*
1295  * Update arp table
1296  *
1297 */
1298 void
1299 mib_arp_update(void)
1300 {
1301 	struct mibarp *at, *at1;
1302 	size_t needed;
1303 	u_char *buf, *next;
1304 	struct rt_msghdr *rtm;
1305 
1306 	if (in_update_arp)
1307 		return;		/* Aaargh */
1308 	in_update_arp = 1;
1309 
1310 	TAILQ_FOREACH(at, &mibarp_list, link)
1311 		at->flags &= ~MIBARP_FOUND;
1312 
1313 	if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, 0, &needed)) == NULL) {
1314 		in_update_arp = 0;
1315 		return;
1316 	}
1317 
1318 	next = buf;
1319 	while (next < buf + needed) {
1320 		rtm = (struct rt_msghdr *)(void *)next;
1321 		next += rtm->rtm_msglen;
1322 		handle_rtmsg(rtm);
1323 	}
1324 	free(buf);
1325 
1326 	at = TAILQ_FIRST(&mibarp_list);
1327 	while (at != NULL) {
1328 		at1 = TAILQ_NEXT(at, link);
1329 		if (!(at->flags & MIBARP_FOUND))
1330 			mib_arp_delete(at);
1331 		at = at1;
1332 	}
1333 	mibarpticks = get_ticks();
1334 	in_update_arp = 0;
1335 }
1336 
1337 
1338 /*
1339  * Intput on the routing socket.
1340  */
1341 static void
1342 route_input(int fd, void *udata __unused)
1343 {
1344 	u_char	buf[1024 * 16];
1345 	ssize_t n;
1346 	struct rt_msghdr *rtm;
1347 
1348 	if ((n = read(fd, buf, sizeof(buf))) == -1)
1349 		err(1, "read(rt_socket)");
1350 
1351 	if (n == 0)
1352 		errx(1, "EOF on rt_socket");
1353 
1354 	rtm = (struct rt_msghdr *)(void *)buf;
1355 	if ((size_t)n != rtm->rtm_msglen)
1356 		errx(1, "n=%zu, rtm_msglen=%u", (size_t)n, rtm->rtm_msglen);
1357 
1358 	handle_rtmsg(rtm);
1359 }
1360 
1361 /*
1362  * execute and SIOCAIFADDR
1363  */
1364 static int
1365 siocaifaddr(char *ifname, struct in_addr addr, struct in_addr mask,
1366     struct in_addr bcast)
1367 {
1368 	struct ifaliasreq addreq;
1369 	struct sockaddr_in *sa;
1370 
1371 	memset(&addreq, 0, sizeof(addreq));
1372 	strncpy(addreq.ifra_name, ifname, sizeof(addreq.ifra_name));
1373 
1374 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_addr;
1375 	sa->sin_family = AF_INET;
1376 	sa->sin_len = sizeof(*sa);
1377 	sa->sin_addr = addr;
1378 
1379 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_mask;
1380 	sa->sin_family = AF_INET;
1381 	sa->sin_len = sizeof(*sa);
1382 	sa->sin_addr = mask;
1383 
1384 	sa = (struct sockaddr_in *)(void *)&addreq.ifra_broadaddr;
1385 	sa->sin_family = AF_INET;
1386 	sa->sin_len = sizeof(*sa);
1387 	sa->sin_addr = bcast;
1388 
1389 	return (ioctl(mib_netsock, SIOCAIFADDR, &addreq));
1390 }
1391 
1392 /*
1393  * Exececute a SIOCDIFADDR
1394  */
1395 static int
1396 siocdifaddr(const char *ifname, struct in_addr addr)
1397 {
1398 	struct ifreq delreq;
1399 	struct sockaddr_in *sa;
1400 
1401 	memset(&delreq, 0, sizeof(delreq));
1402 	strncpy(delreq.ifr_name, ifname, sizeof(delreq.ifr_name));
1403 	sa = (struct sockaddr_in *)(void *)&delreq.ifr_addr;
1404 	sa->sin_family = AF_INET;
1405 	sa->sin_len = sizeof(*sa);
1406 	sa->sin_addr = addr;
1407 
1408 	return (ioctl(mib_netsock, SIOCDIFADDR, &delreq));
1409 }
1410 
1411 /*
1412  * Verify an interface address without fetching the entire list
1413  */
1414 static int
1415 verify_ifa(const char *name, struct mibifa *ifa)
1416 {
1417 	struct ifreq req;
1418 	struct sockaddr_in *sa;
1419 
1420 	memset(&req, 0, sizeof(req));
1421 	strncpy(req.ifr_name, name, sizeof(req.ifr_name));
1422 	sa = (struct sockaddr_in *)(void *)&req.ifr_addr;
1423 	sa->sin_family = AF_INET;
1424 	sa->sin_len = sizeof(*sa);
1425 	sa->sin_addr = ifa->inaddr;
1426 
1427 	if (ioctl(mib_netsock, SIOCGIFADDR, &req) == -1)
1428 		return (-1);
1429 	if (ifa->inaddr.s_addr != sa->sin_addr.s_addr) {
1430 		syslog(LOG_ERR, "%s: address mismatch", __func__);
1431 		return (-1);
1432 	}
1433 
1434 	if (ioctl(mib_netsock, SIOCGIFNETMASK, &req) == -1)
1435 		return (-1);
1436 	if (ifa->inmask.s_addr != sa->sin_addr.s_addr) {
1437 		syslog(LOG_ERR, "%s: netmask mismatch", __func__);
1438 		return (-1);
1439 	}
1440 	return (0);
1441 }
1442 
1443 /*
1444  * Restore a deleted interface address. Don't wait for the routing socket
1445  * to update us.
1446  */
1447 void
1448 mib_undestroy_ifa(struct mibifa *ifa)
1449 {
1450 	struct mibif *ifp;
1451 
1452 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
1453 		/* keep it destroyed */
1454 		return;
1455 
1456 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast))
1457 		/* keep it destroyed */
1458 		return;
1459 
1460 	ifa->flags &= ~MIBIFA_DESTROYED;
1461 }
1462 
1463 /*
1464  * Destroy an interface address
1465  */
1466 int
1467 mib_destroy_ifa(struct mibifa *ifa)
1468 {
1469 	struct mibif *ifp;
1470 
1471 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1472 		/* ups. */
1473 		mib_iflist_bad = 1;
1474 		return (-1);
1475 	}
1476 	if (siocdifaddr(ifp->name, ifa->inaddr)) {
1477 		/* ups. */
1478 		syslog(LOG_ERR, "SIOCDIFADDR: %m");
1479 		mib_iflist_bad = 1;
1480 		return (-1);
1481 	}
1482 	ifa->flags |= MIBIFA_DESTROYED;
1483 	return (0);
1484 }
1485 
1486 /*
1487  * Rollback the modification of an address. Don't bother to wait for
1488  * the routing socket.
1489  */
1490 void
1491 mib_unmodify_ifa(struct mibifa *ifa)
1492 {
1493 	struct mibif *ifp;
1494 
1495 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1496 		/* ups. */
1497 		mib_iflist_bad = 1;
1498 		return;
1499 	}
1500 
1501 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1502 		/* ups. */
1503 		mib_iflist_bad = 1;
1504 		return;
1505 	}
1506 }
1507 
1508 /*
1509  * Modify an IFA.
1510  */
1511 int
1512 mib_modify_ifa(struct mibifa *ifa)
1513 {
1514 	struct mibif *ifp;
1515 
1516 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1517 		/* ups. */
1518 		mib_iflist_bad = 1;
1519 		return (-1);
1520 	}
1521 
1522 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1523 		/* ups. */
1524 		mib_iflist_bad = 1;
1525 		return (-1);
1526 	}
1527 
1528 	if (verify_ifa(ifp->name, ifa)) {
1529 		/* ups. */
1530 		mib_iflist_bad = 1;
1531 		return (-1);
1532 	}
1533 
1534 	return (0);
1535 }
1536 
1537 /*
1538  * Destroy a freshly created interface address. Don't bother to wait for
1539  * the routing socket.
1540  */
1541 void
1542 mib_uncreate_ifa(struct mibifa *ifa)
1543 {
1544 	struct mibif *ifp;
1545 
1546 	if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1547 		/* ups. */
1548 		mib_iflist_bad = 1;
1549 		return;
1550 	}
1551 	if (siocdifaddr(ifp->name, ifa->inaddr)) {
1552 		/* ups. */
1553 		mib_iflist_bad = 1;
1554 		return;
1555 	}
1556 
1557 	destroy_ifa(ifa);
1558 }
1559 
1560 /*
1561  * Create a new ifa and verify it
1562  */
1563 struct mibifa *
1564 mib_create_ifa(u_int ifindex, struct in_addr addr, struct in_addr mask,
1565     struct in_addr bcast)
1566 {
1567 	struct mibif *ifp;
1568 	struct mibifa *ifa;
1569 
1570 	if ((ifp = mib_find_if(ifindex)) == NULL)
1571 		return (NULL);
1572 	if ((ifa = alloc_ifa(ifindex, addr)) == NULL)
1573 		return (NULL);
1574 	ifa->inmask = mask;
1575 	ifa->inbcast = bcast;
1576 
1577 	if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1578 		syslog(LOG_ERR, "%s: %m", __func__);
1579 		destroy_ifa(ifa);
1580 		return (NULL);
1581 	}
1582 	if (verify_ifa(ifp->name, ifa)) {
1583 		destroy_ifa(ifa);
1584 		return (NULL);
1585 	}
1586 	return (ifa);
1587 }
1588 
1589 /*
1590  * Get all cloning interfaces and make them dynamic.
1591  * Hah! Whe should probably do this on a periodic basis (XXX).
1592  */
1593 static void
1594 get_cloners(void)
1595 {
1596 	struct if_clonereq req;
1597 	char *buf, *cp;
1598 	int i;
1599 
1600 	memset(&req, 0, sizeof(req));
1601 	if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1602 		syslog(LOG_ERR, "get cloners: %m");
1603 		return;
1604 	}
1605 	if ((buf = malloc(req.ifcr_total * IFNAMSIZ)) == NULL) {
1606 		syslog(LOG_ERR, "%m");
1607 		return;
1608 	}
1609 	req.ifcr_count = req.ifcr_total;
1610 	req.ifcr_buffer = buf;
1611 	if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1612 		syslog(LOG_ERR, "get cloners: %m");
1613 		free(buf);
1614 		return;
1615 	}
1616 	for (cp = buf, i = 0; i < req.ifcr_total; i++, cp += IFNAMSIZ)
1617 		mib_if_set_dyn(cp);
1618 	free(buf);
1619 }
1620 
1621 /*
1622  * Idle function
1623  */
1624 static void
1625 mibII_idle(void *arg __unused)
1626 {
1627 	struct mibifa *ifa;
1628 
1629 	if (mib_iflist_bad) {
1630 		TAILQ_FOREACH(ifa, &mibifa_list, link)
1631 			ifa->flags &= ~MIBIFA_DESTROYED;
1632 
1633 		/* assume, that all cloning interfaces are dynamic */
1634 		get_cloners();
1635 
1636 		mib_refresh_iflist();
1637 		update_ifa_info();
1638 		mib_arp_update();
1639 		mib_iflist_bad = 0;
1640 	}
1641 
1642 	mib_arp_update();
1643 }
1644 
1645 
1646 /*
1647  * Start the module
1648  */
1649 static void
1650 mibII_start(void)
1651 {
1652 	if ((route_fd = fd_select(route, route_input, NULL, module)) == NULL) {
1653 		syslog(LOG_ERR, "fd_select(route): %m");
1654 		return;
1655 	}
1656 	mib_refresh_iflist();
1657 	update_ifa_info();
1658 	mib_arp_update();
1659 	(void)mib_fetch_route();
1660 	mib_iftable_last_change = 0;
1661 	mib_ifstack_last_change = 0;
1662 
1663 	ifmib_reg = or_register(&oid_ifMIB,
1664 	    "The MIB module to describe generic objects for network interface"
1665 	    " sub-layers.", module);
1666 
1667 	ipmib_reg = or_register(&oid_ipMIB,
1668 	   "The MIB module for managing IP and ICMP implementations, but "
1669 	   "excluding their management of IP routes.", module);
1670 
1671 	tcpmib_reg = or_register(&oid_tcpMIB,
1672 	   "The MIB module for managing TCP implementations.", module);
1673 
1674 	udpmib_reg = or_register(&oid_udpMIB,
1675 	   "The MIB module for managing UDP implementations.", module);
1676 
1677 	ipForward_reg = or_register(&oid_ipForward,
1678 	   "The MIB module for the display of CIDR multipath IP Routes.",
1679 	   module);
1680 
1681 	mibII_poll_timer = NULL;
1682 	mibII_poll_ticks = MIBII_POLL_TICKS;
1683 	mibif_restart_mibII_poll_timer();
1684 }
1685 
1686 /*
1687  * Initialize the module
1688  */
1689 static int
1690 mibII_init(struct lmodule *mod, int argc __unused, char *argv[] __unused)
1691 {
1692 	size_t len;
1693 
1694 	module = mod;
1695 
1696 	len = sizeof(clockinfo);
1697 	if (sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0) == -1) {
1698 		syslog(LOG_ERR, "kern.clockrate: %m");
1699 		return (-1);
1700 	}
1701 	if (len != sizeof(clockinfo)) {
1702 		syslog(LOG_ERR, "kern.clockrate: wrong size");
1703 		return (-1);
1704 	}
1705 
1706 	if ((route = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) == -1) {
1707 		syslog(LOG_ERR, "PF_ROUTE: %m");
1708 		return (-1);
1709 	}
1710 
1711 	if ((mib_netsock = socket(PF_INET, SOCK_DGRAM, 0)) == -1) {
1712 		syslog(LOG_ERR, "PF_INET: %m");
1713 		(void)close(route);
1714 		return (-1);
1715 	}
1716 	(void)shutdown(mib_netsock, SHUT_RDWR);
1717 
1718 	/* assume, that all cloning interfaces are dynamic */
1719 	get_cloners();
1720 
1721 	return (0);
1722 }
1723 
1724 static int
1725 mibII_fini(void)
1726 {
1727 	if (mibII_poll_timer != NULL ) {
1728 		timer_stop(mibII_poll_timer);
1729 		mibII_poll_timer = NULL;
1730 	}
1731 
1732 	if (route_fd != NULL)
1733 		fd_deselect(route_fd);
1734 	if (route != -1)
1735 		(void)close(route);
1736 	if (mib_netsock != -1)
1737 		(void)close(mib_netsock);
1738 	/* XXX free memory */
1739 
1740 	or_unregister(ipForward_reg);
1741 	or_unregister(udpmib_reg);
1742 	or_unregister(tcpmib_reg);
1743 	or_unregister(ipmib_reg);
1744 	or_unregister(ifmib_reg);
1745 
1746 	return (0);
1747 }
1748 
1749 static void
1750 mibII_loading(const struct lmodule *mod, int loaded)
1751 {
1752 	struct mibif *ifp;
1753 
1754 	if (loaded == 1)
1755 		return;
1756 
1757 	TAILQ_FOREACH(ifp, &mibif_list, link)
1758 		if (ifp->xnotify_mod == mod) {
1759 			ifp->xnotify_mod = NULL;
1760 			ifp->xnotify_data = NULL;
1761 			ifp->xnotify = NULL;
1762 		}
1763 
1764 	mib_unregister_newif(mod);
1765 }
1766 
1767 const struct snmp_module config = {
1768 	"This module implements the interface and ip groups.",
1769 	mibII_init,
1770 	mibII_fini,
1771 	NULL,		/* idle */
1772 	NULL,		/* dump */
1773 	NULL,		/* config */
1774 	mibII_start,
1775 	NULL,
1776 	mibII_ctree,
1777 	mibII_CTREE_SIZE,
1778 	mibII_loading
1779 };
1780 
1781 /*
1782  * Should have a list of these attached to each interface.
1783  */
1784 void *
1785 mibif_notify(struct mibif *ifp, const struct lmodule *mod,
1786     mibif_notify_f func, void *data)
1787 {
1788 	ifp->xnotify = func;
1789 	ifp->xnotify_data = data;
1790 	ifp->xnotify_mod = mod;
1791 
1792 	return (ifp);
1793 }
1794 
1795 void
1796 mibif_unnotify(void *arg)
1797 {
1798 	struct mibif *ifp = arg;
1799 
1800 	ifp->xnotify = NULL;
1801 	ifp->xnotify_data = NULL;
1802 	ifp->xnotify_mod = NULL;
1803 }
1804