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 *
mib_find_if(u_int idx)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 *
mib_find_if_sys(u_int sysindex)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 *
mib_find_if_name(const char * name)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
mib_if_is_dyn(const char * name)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
mib_if_set_dyn(const char * name)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 strlcpy(d->name, name, sizeof(d->name));
208 SLIST_INSERT_HEAD(&mibdynif_list, d, link);
209 }
210
211 /*
212 * register for interface creations
213 */
214 int
mib_register_newif(int (* func)(struct mibif *),const struct lmodule * mod)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
mib_unregister_newif(const struct lmodule * mod)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 *
mib_first_if(void)250 mib_first_if(void)
251 {
252 return (TAILQ_FIRST(&mibif_list));
253 }
254 struct mibif *
mib_next_if(const struct mibif * ifp)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
mib_if_admin(struct mibif * ifp,int up)264 mib_if_admin(struct mibif *ifp, int up)
265 {
266 struct ifreq ifr;
267
268 strlcpy(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
link_trap(struct mibif * ifp,int up)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
fetch_generic_mib(struct mibif * ifp,const struct ifmibdata * old)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, nitems(name), &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
update_hc_counters(void * arg __unused)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
mibif_reset_hc_timer(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, ticks,
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
mibif_restart_mibII_poll_timer(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
mib_fetch_ifmib(struct mibif * ifp)440 mib_fetch_ifmib(struct mibif *ifp)
441 {
442 static int kmib[2] = { -1, 0 }; /* for sysctl net.ifdescr_maxlen */
443
444 int name[6];
445 size_t kmiblen = nitems(kmib);
446 size_t len;
447 void *newmib;
448 struct ifmibdata oldmib = ifp->mib;
449 struct ifreq irr;
450 u_int alias_maxlen = MIBIF_ALIAS_SIZE_MAX;
451
452 if (fetch_generic_mib(ifp, &oldmib) == -1)
453 return (-1);
454
455 /*
456 * Quoting RFC2863, 3.1.15: "... LinkUp and linkDown traps are
457 * generated just after ifOperStatus leaves, or just before it
458 * enters, the down state, respectively;"
459 */
460 if (ifp->trap_enable && ifp->mib.ifmd_data.ifi_link_state !=
461 oldmib.ifmd_data.ifi_link_state &&
462 (ifp->mib.ifmd_data.ifi_link_state == LINK_STATE_DOWN ||
463 oldmib.ifmd_data.ifi_link_state == LINK_STATE_DOWN))
464 link_trap(ifp, ifp->mib.ifmd_data.ifi_link_state ==
465 LINK_STATE_UP ? 1 : 0);
466
467 ifp->flags &= ~(MIBIF_HIGHSPEED | MIBIF_VERYHIGHSPEED);
468 if (ifp->mib.ifmd_data.ifi_baudrate > 20000000) {
469 ifp->flags |= MIBIF_HIGHSPEED;
470 if (ifp->mib.ifmd_data.ifi_baudrate > 650000000)
471 ifp->flags |= MIBIF_VERYHIGHSPEED;
472 }
473 if (ifp->mib.ifmd_data.ifi_baudrate > mibif_maxspeed) {
474 mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
475 mibif_reset_hc_timer();
476 }
477
478 /*
479 * linkspecific MIB
480 */
481 name[0] = CTL_NET;
482 name[1] = PF_LINK;
483 name[2] = NETLINK_GENERIC;
484 name[3] = IFMIB_IFDATA;
485 name[4] = ifp->sysindex;
486 name[5] = IFDATA_LINKSPECIFIC;
487 if (sysctl(name, nitems(name), NULL, &len, NULL, 0) == -1) {
488 syslog(LOG_WARNING, "sysctl linkmib estimate (%s): %m",
489 ifp->name);
490 if (ifp->specmib != NULL) {
491 ifp->specmib = NULL;
492 ifp->specmiblen = 0;
493 }
494 goto out;
495 }
496 if (len == 0) {
497 if (ifp->specmib != NULL) {
498 ifp->specmib = NULL;
499 ifp->specmiblen = 0;
500 }
501 goto out;
502 }
503
504 if (ifp->specmiblen != len) {
505 if ((newmib = realloc(ifp->specmib, len)) == NULL) {
506 ifp->specmib = NULL;
507 ifp->specmiblen = 0;
508 goto out;
509 }
510 ifp->specmib = newmib;
511 ifp->specmiblen = len;
512 }
513 if (sysctl(name, nitems(name), ifp->specmib, &len, NULL, 0) == -1) {
514 syslog(LOG_WARNING, "sysctl linkmib (%s): %m", ifp->name);
515 if (ifp->specmib != NULL) {
516 ifp->specmib = NULL;
517 ifp->specmiblen = 0;
518 }
519 }
520
521 out:
522 /*
523 * Find sysctl mib for net.ifdescr_maxlen (one time).
524 * kmib[0] == -1 at first call to mib_fetch_ifmib().
525 * Then kmib[0] > 0 if we found sysctl mib for net.ifdescr_maxlen.
526 * Else, kmib[0] == 0 (unexpected error from a kernel).
527 */
528 if (kmib[0] < 0 &&
529 sysctlnametomib("net.ifdescr_maxlen", kmib, &kmiblen) < 0) {
530 kmib[0] = 0;
531 syslog(LOG_WARNING, "sysctlnametomib net.ifdescr_maxlen: %m");
532 }
533
534 /*
535 * Fetch net.ifdescr_maxlen value every time to catch up with changes.
536 */
537 len = sizeof(alias_maxlen);
538 if (kmib[0] > 0 && sysctl(kmib, 2, &alias_maxlen, &len, NULL, 0) < 0) {
539 /* unexpected error from the kernel, use default value */
540 alias_maxlen = MIBIF_ALIAS_SIZE_MAX;
541 syslog(LOG_WARNING, "sysctl net.ifdescr_maxlen: %m");
542 }
543
544 /*
545 * Kernel limit might be decreased after interfaces got
546 * their descriptions assigned. Try to obtain them anyway.
547 */
548 if (alias_maxlen == 0)
549 alias_maxlen = MIBIF_ALIAS_SIZE_MAX;
550
551 /*
552 * Allocate maximum memory for a buffer and later reallocate
553 * to free extra memory.
554 */
555 if ((ifp->alias = malloc(alias_maxlen)) == NULL) {
556 syslog(LOG_WARNING, "malloc(%d) failed: %m", (int)alias_maxlen);
557 goto fin;
558 }
559
560 strlcpy(irr.ifr_name, ifp->name, sizeof(irr.ifr_name));
561 irr.ifr_buffer.buffer = ifp->alias;
562 irr.ifr_buffer.length = alias_maxlen;
563 if (ioctl(mib_netsock, SIOCGIFDESCR, &irr) == -1) {
564 free(ifp->alias);
565 ifp->alias = NULL;
566 if (errno != ENOMSG)
567 syslog(LOG_WARNING, "SIOCGIFDESCR (%s): %m", ifp->name);
568 } else if (irr.ifr_buffer.buffer == NULL) {
569 free(ifp->alias);
570 ifp->alias = NULL;
571 syslog(LOG_WARNING, "SIOCGIFDESCR (%s): too long (%zu)",
572 ifp->name, irr.ifr_buffer.length);
573 } else {
574 ifp->alias_size = strnlen(ifp->alias, alias_maxlen) + 1;
575
576 if (ifp->alias_size > MIBIF_ALIAS_SIZE)
577 ifp->alias_size = MIBIF_ALIAS_SIZE;
578
579 if (ifp->alias_size < alias_maxlen)
580 ifp->alias = realloc(ifp->alias, ifp->alias_size);
581 }
582
583 fin:
584 ifp->mibtick = get_ticks();
585 return (0);
586 }
587
588 /* find first/next address for a given interface */
589 struct mibifa *
mib_first_ififa(const struct mibif * ifp)590 mib_first_ififa(const struct mibif *ifp)
591 {
592 struct mibifa *ifa;
593
594 TAILQ_FOREACH(ifa, &mibifa_list, link)
595 if (ifp->index == ifa->ifindex)
596 return (ifa);
597 return (NULL);
598 }
599
600 struct mibifa *
mib_next_ififa(struct mibifa * ifa0)601 mib_next_ififa(struct mibifa *ifa0)
602 {
603 struct mibifa *ifa;
604
605 ifa = ifa0;
606 while ((ifa = TAILQ_NEXT(ifa, link)) != NULL)
607 if (ifa->ifindex == ifa0->ifindex)
608 return (ifa);
609 return (NULL);
610 }
611
612 /*
613 * Allocate a new IFA
614 */
615 static struct mibifa *
alloc_ifa(u_int ifindex,struct in_addr addr)616 alloc_ifa(u_int ifindex, struct in_addr addr)
617 {
618 struct mibifa *ifa;
619 uint32_t ha;
620
621 if ((ifa = malloc(sizeof(struct mibifa))) == NULL) {
622 syslog(LOG_ERR, "ifa: %m");
623 return (NULL);
624 }
625 ifa->inaddr = addr;
626 ifa->ifindex = ifindex;
627
628 ha = ntohl(ifa->inaddr.s_addr);
629 ifa->index.len = 4;
630 ifa->index.subs[0] = (ha >> 24) & 0xff;
631 ifa->index.subs[1] = (ha >> 16) & 0xff;
632 ifa->index.subs[2] = (ha >> 8) & 0xff;
633 ifa->index.subs[3] = (ha >> 0) & 0xff;
634
635 ifa->flags = 0;
636 ifa->inbcast.s_addr = 0;
637 ifa->inmask.s_addr = 0xffffffff;
638
639 INSERT_OBJECT_OID(ifa, &mibifa_list);
640
641 return (ifa);
642 }
643
644 /*
645 * Delete an interface address
646 */
647 static void
destroy_ifa(struct mibifa * ifa)648 destroy_ifa(struct mibifa *ifa)
649 {
650 TAILQ_REMOVE(&mibifa_list, ifa, link);
651 free(ifa);
652 }
653
654
655 /*
656 * Helper routine to extract the sockaddr structures from a routing
657 * socket message.
658 */
659 void
mib_extract_addrs(int addrs,u_char * info,struct sockaddr ** out)660 mib_extract_addrs(int addrs, u_char *info, struct sockaddr **out)
661 {
662 u_int i;
663
664 for (i = 0; i < RTAX_MAX; i++) {
665 if ((addrs & (1 << i)) != 0) {
666 *out = (struct sockaddr *)(void *)info;
667 info += roundup((*out)->sa_len, sizeof(long));
668 } else
669 *out = NULL;
670 out++;
671 }
672 }
673
674 /*
675 * save the phys address of an interface. Handle receive address entries here.
676 */
677 static void
get_physaddr(struct mibif * ifp,struct sockaddr_dl * sdl,u_char * ptr)678 get_physaddr(struct mibif *ifp, struct sockaddr_dl *sdl, u_char *ptr)
679 {
680 u_char *np;
681 struct mibrcvaddr *rcv;
682
683 if (sdl->sdl_alen == 0) {
684 /* no address */
685 if (ifp->physaddrlen != 0) {
686 if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
687 ifp->physaddrlen)) != NULL)
688 mib_rcvaddr_delete(rcv);
689 free(ifp->physaddr);
690 ifp->physaddr = NULL;
691 ifp->physaddrlen = 0;
692 }
693 return;
694 }
695
696 if (ifp->physaddrlen != sdl->sdl_alen) {
697 /* length changed */
698 if (ifp->physaddrlen) {
699 /* delete olf receive address */
700 if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
701 ifp->physaddrlen)) != NULL)
702 mib_rcvaddr_delete(rcv);
703 }
704 if ((np = realloc(ifp->physaddr, sdl->sdl_alen)) == NULL) {
705 free(ifp->physaddr);
706 ifp->physaddr = NULL;
707 ifp->physaddrlen = 0;
708 return;
709 }
710 ifp->physaddr = np;
711 ifp->physaddrlen = sdl->sdl_alen;
712
713 } else if (memcmp(ifp->physaddr, ptr, ifp->physaddrlen) == 0) {
714 /* no change */
715 return;
716
717 } else {
718 /* address changed */
719
720 /* delete olf receive address */
721 if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
722 ifp->physaddrlen)) != NULL)
723 mib_rcvaddr_delete(rcv);
724 }
725
726 memcpy(ifp->physaddr, ptr, ifp->physaddrlen);
727
728 /* make new receive address */
729 if ((rcv = mib_rcvaddr_create(ifp, ifp->physaddr, ifp->physaddrlen)) != NULL)
730 rcv->flags |= MIBRCVADDR_HW;
731 }
732
733 /*
734 * Free an interface
735 */
736 static void
mibif_free(struct mibif * ifp)737 mibif_free(struct mibif *ifp)
738 {
739 struct mibif *ifp1;
740 struct mibindexmap *map;
741 struct mibifa *ifa, *ifa1;
742 struct mibrcvaddr *rcv, *rcv1;
743 struct mibarp *at, *at1;
744
745 if (ifp->xnotify != NULL)
746 (*ifp->xnotify)(ifp, MIBIF_NOTIFY_DESTROY, ifp->xnotify_data);
747
748 (void)mib_ifstack_delete(ifp, NULL);
749 (void)mib_ifstack_delete(NULL, ifp);
750
751 TAILQ_REMOVE(&mibif_list, ifp, link);
752
753 /* if this was the fastest interface - recompute this */
754 if (ifp->mib.ifmd_data.ifi_baudrate == mibif_maxspeed) {
755 mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
756 TAILQ_FOREACH(ifp1, &mibif_list, link)
757 if (ifp1->mib.ifmd_data.ifi_baudrate > mibif_maxspeed)
758 mibif_maxspeed =
759 ifp1->mib.ifmd_data.ifi_baudrate;
760 mibif_reset_hc_timer();
761 }
762
763 if (ifp->alias != NULL) {
764 free(ifp->alias);
765 ifp->alias = NULL;
766 }
767 free(ifp->private);
768 ifp->private = NULL;
769 free(ifp->physaddr);
770 ifp->physaddr = NULL;
771 free(ifp->specmib);
772 ifp->specmib = NULL;
773
774 STAILQ_FOREACH(map, &mibindexmap_list, link)
775 if (map->mibif == ifp) {
776 map->mibif = NULL;
777 break;
778 }
779
780 /* purge interface addresses */
781 ifa = TAILQ_FIRST(&mibifa_list);
782 while (ifa != NULL) {
783 ifa1 = TAILQ_NEXT(ifa, link);
784 if (ifa->ifindex == ifp->index)
785 destroy_ifa(ifa);
786 ifa = ifa1;
787 }
788
789 /* purge receive addresses */
790 rcv = TAILQ_FIRST(&mibrcvaddr_list);
791 while (rcv != NULL) {
792 rcv1 = TAILQ_NEXT(rcv, link);
793 if (rcv->ifindex == ifp->index)
794 mib_rcvaddr_delete(rcv);
795 rcv = rcv1;
796 }
797
798 /* purge ARP entries */
799 at = TAILQ_FIRST(&mibarp_list);
800 while (at != NULL) {
801 at1 = TAILQ_NEXT(at, link);
802 if (at->index.subs[0] == ifp->index)
803 mib_arp_delete(at);
804 at = at1;
805 }
806
807 free(ifp);
808 ifp = NULL;
809 mib_if_number--;
810 mib_iftable_last_change = this_tick;
811 }
812
813 /*
814 * Create a new interface
815 */
816 static struct mibif *
mibif_create(u_int sysindex,const char * name)817 mibif_create(u_int sysindex, const char *name)
818 {
819 struct mibif *ifp;
820 struct mibindexmap *map;
821
822 if ((ifp = malloc(sizeof(*ifp))) == NULL) {
823 syslog(LOG_WARNING, "%s: %m", __func__);
824 return (NULL);
825 }
826 memset(ifp, 0, sizeof(*ifp));
827 if ((ifp->private = malloc(sizeof(struct mibif_private))) == NULL) {
828 syslog(LOG_WARNING, "%s: %m", __func__);
829 free(ifp);
830 return (NULL);
831 }
832 memset(ifp->private, 0, sizeof(struct mibif_private));
833
834 ifp->sysindex = sysindex;
835 strlcpy(ifp->name, name, sizeof(ifp->name));
836 strlcpy(ifp->descr, name, sizeof(ifp->descr));
837 ifp->spec_oid = oid_zeroDotZero;
838
839 map = NULL;
840 if (!mib_if_is_dyn(ifp->name)) {
841 /* non-dynamic. look whether we know the interface */
842 STAILQ_FOREACH(map, &mibindexmap_list, link)
843 if (strcmp(map->name, ifp->name) == 0) {
844 ifp->index = map->ifindex;
845 map->mibif = ifp;
846 break;
847 }
848 /* assume it has a connector if it is not dynamic */
849 ifp->has_connector = 1;
850 ifp->trap_enable = 1;
851 }
852 if (map == NULL) {
853 /* new interface - get new index */
854 if (next_if_index > 0x7fffffff)
855 errx(1, "ifindex wrap");
856
857 if ((map = malloc(sizeof(*map))) == NULL) {
858 syslog(LOG_ERR, "ifmap: %m");
859 free(ifp);
860 return (NULL);
861 }
862 map->ifindex = next_if_index++;
863 map->sysindex = ifp->sysindex;
864 strcpy(map->name, ifp->name);
865 map->mibif = ifp;
866 STAILQ_INSERT_TAIL(&mibindexmap_list, map, link);
867 } else {
868 /* re-instantiate. Introduce a counter discontinuity */
869 ifp->counter_disc = get_ticks();
870 }
871 ifp->index = map->ifindex;
872 ifp->mib.ifmd_data.ifi_link_state = LINK_STATE_UNKNOWN;
873
874 INSERT_OBJECT_INT(ifp, &mibif_list);
875 mib_if_number++;
876 mib_iftable_last_change = this_tick;
877
878 /* instantiate default ifStack entries */
879 (void)mib_ifstack_create(ifp, NULL);
880 (void)mib_ifstack_create(NULL, ifp);
881
882 return (ifp);
883 }
884
885 /*
886 * Inform all interested parties about a new interface
887 */
888 static void
notify_newif(struct mibif * ifp)889 notify_newif(struct mibif *ifp)
890 {
891 struct newifreg *reg;
892
893 TAILQ_FOREACH(reg, &newifreg_list, link)
894 if ((*reg->func)(ifp))
895 return;
896 }
897
898 /*
899 * This is called for new interfaces after we have fetched the interface
900 * MIB. If this is a broadcast interface try to guess the broadcast address
901 * depending on the interface type.
902 */
903 static void
check_llbcast(struct mibif * ifp)904 check_llbcast(struct mibif *ifp)
905 {
906 static u_char ether_bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
907 struct mibrcvaddr *rcv;
908
909 if (!(ifp->mib.ifmd_flags & IFF_BROADCAST))
910 return;
911
912 switch (ifp->mib.ifmd_data.ifi_type) {
913
914 case IFT_ETHER:
915 case IFT_FDDI:
916 case IFT_ISO88025:
917 case IFT_L2VLAN:
918 if (mib_find_rcvaddr(ifp->index, ether_bcast, 6) == NULL &&
919 (rcv = mib_rcvaddr_create(ifp, ether_bcast, 6)) != NULL)
920 rcv->flags |= MIBRCVADDR_BCAST;
921 break;
922 }
923 }
924
925
926 /*
927 * Retrieve the current interface list from the system.
928 */
929 void
mib_refresh_iflist(void)930 mib_refresh_iflist(void)
931 {
932 struct mibif *ifp, *ifp1;
933 size_t len;
934 u_short idx;
935 int name[6];
936 int count;
937 struct ifmibdata mib;
938
939 TAILQ_FOREACH(ifp, &mibif_list, link)
940 ifp->flags &= ~MIBIF_FOUND;
941
942 len = sizeof(count);
943 if (sysctlbyname("net.link.generic.system.ifcount", &count, &len,
944 NULL, 0) == -1) {
945 syslog(LOG_ERR, "ifcount: %m");
946 return;
947 }
948 name[0] = CTL_NET;
949 name[1] = PF_LINK;
950 name[2] = NETLINK_GENERIC;
951 name[3] = IFMIB_IFDATA;
952 name[5] = IFDATA_GENERAL;
953 for (idx = 1; idx <= count; idx++) {
954 name[4] = idx;
955 len = sizeof(mib);
956 if (sysctl(name, nitems(name), &mib, &len, NULL, 0) == -1) {
957 if (errno == ENOENT)
958 continue;
959 syslog(LOG_ERR, "ifmib(%u): %m", idx);
960 return;
961 }
962 if ((ifp = mib_find_if_sys(idx)) != NULL) {
963 ifp->flags |= MIBIF_FOUND;
964 continue;
965 }
966 /* Unknown interface - create */
967 if ((ifp = mibif_create(idx, mib.ifmd_name)) != NULL) {
968 ifp->flags |= MIBIF_FOUND;
969 (void)mib_fetch_ifmib(ifp);
970 check_llbcast(ifp);
971 notify_newif(ifp);
972 }
973 }
974
975 /*
976 * Purge interfaces that disappeared
977 */
978 ifp = TAILQ_FIRST(&mibif_list);
979 while (ifp != NULL) {
980 ifp1 = TAILQ_NEXT(ifp, link);
981 if (!(ifp->flags & MIBIF_FOUND))
982 mibif_free(ifp);
983 ifp = ifp1;
984 }
985 }
986
987 /*
988 * Find an interface address
989 */
990 struct mibifa *
mib_find_ifa(struct in_addr addr)991 mib_find_ifa(struct in_addr addr)
992 {
993 struct mibifa *ifa;
994
995 TAILQ_FOREACH(ifa, &mibifa_list, link)
996 if (ifa->inaddr.s_addr == addr.s_addr)
997 return (ifa);
998 return (NULL);
999 }
1000
1001 /*
1002 * Process a new ARP entry
1003 */
1004 static void
process_arp(const struct rt_msghdr * rtm,const struct sockaddr_dl * sdl,const struct sockaddr_in * sa)1005 process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl,
1006 const struct sockaddr_in *sa)
1007 {
1008 struct mibif *ifp;
1009 struct mibarp *at;
1010
1011 /* IP arp table entry */
1012 if (sdl->sdl_alen == 0)
1013 return;
1014 if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL)
1015 return;
1016 /* have a valid entry */
1017 if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL &&
1018 (at = mib_arp_create(ifp, sa->sin_addr,
1019 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
1020 return;
1021
1022 if (rtm->rtm_rmx.rmx_expire == 0)
1023 at->flags |= MIBARP_PERM;
1024 else
1025 at->flags &= ~MIBARP_PERM;
1026 at->flags |= MIBARP_FOUND;
1027 }
1028
1029 /*
1030 * Handle a routing socket message.
1031 */
1032 static void
handle_rtmsg(struct rt_msghdr * rtm)1033 handle_rtmsg(struct rt_msghdr *rtm)
1034 {
1035 struct sockaddr *addrs[RTAX_MAX];
1036 struct if_msghdr *ifm;
1037 struct ifa_msghdr ifam, *ifamp;
1038 struct ifma_msghdr *ifmam;
1039 #ifdef RTM_IFANNOUNCE
1040 struct if_announcemsghdr *ifan;
1041 #endif
1042 struct mibif *ifp;
1043 struct sockaddr_dl *sdl;
1044 struct sockaddr_in *sa;
1045 struct mibifa *ifa;
1046 struct mibrcvaddr *rcv;
1047 u_char *ptr;
1048
1049 if (rtm->rtm_version != RTM_VERSION) {
1050 syslog(LOG_ERR, "Bogus RTM version %u", rtm->rtm_version);
1051 return;
1052 }
1053
1054 switch (rtm->rtm_type) {
1055
1056 case RTM_NEWADDR:
1057 ifamp = (struct ifa_msghdr *)rtm;
1058 memcpy(&ifam, ifamp, sizeof(ifam));
1059 mib_extract_addrs(ifam.ifam_addrs, (u_char *)(ifamp + 1), addrs);
1060 if (addrs[RTAX_IFA] == NULL || addrs[RTAX_NETMASK] == NULL)
1061 break;
1062
1063 sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
1064 if ((ifa = mib_find_ifa(sa->sin_addr)) == NULL) {
1065 /* unknown address */
1066 if ((ifp = mib_find_if_sys(ifam.ifam_index)) == NULL) {
1067 syslog(LOG_WARNING, "RTM_NEWADDR for unknown "
1068 "interface %u", ifam.ifam_index);
1069 break;
1070 }
1071 if ((ifa = alloc_ifa(ifp->index, sa->sin_addr)) == NULL)
1072 break;
1073 }
1074 sa = (struct sockaddr_in *)(void *)addrs[RTAX_NETMASK];
1075 ifa->inmask = sa->sin_addr;
1076
1077 if (addrs[RTAX_BRD] != NULL) {
1078 sa = (struct sockaddr_in *)(void *)addrs[RTAX_BRD];
1079 ifa->inbcast = sa->sin_addr;
1080 }
1081 ifa->flags |= MIBIFA_FOUND;
1082 break;
1083
1084 case RTM_DELADDR:
1085 ifamp = (struct ifa_msghdr *)rtm;
1086 memcpy(&ifam, ifamp, sizeof(ifam));
1087 mib_extract_addrs(ifam.ifam_addrs, (u_char *)(ifamp + 1), addrs);
1088 if (addrs[RTAX_IFA] == NULL)
1089 break;
1090
1091 sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
1092 if ((ifa = mib_find_ifa(sa->sin_addr)) != NULL) {
1093 ifa->flags |= MIBIFA_FOUND;
1094 if (!(ifa->flags & MIBIFA_DESTROYED))
1095 destroy_ifa(ifa);
1096 }
1097 break;
1098
1099 case RTM_NEWMADDR:
1100 ifmam = (struct ifma_msghdr *)rtm;
1101 mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1102 if (addrs[RTAX_IFA] == NULL ||
1103 addrs[RTAX_IFA]->sa_family != AF_LINK)
1104 break;
1105 sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1106 if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1107 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) {
1108 /* unknown address */
1109 if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) {
1110 syslog(LOG_WARNING, "RTM_NEWMADDR for unknown "
1111 "interface %u", sdl->sdl_index);
1112 break;
1113 }
1114 if ((rcv = mib_rcvaddr_create(ifp,
1115 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
1116 break;
1117 rcv->flags |= MIBRCVADDR_VOLATILE;
1118 }
1119 rcv->flags |= MIBRCVADDR_FOUND;
1120 break;
1121
1122 case RTM_DELMADDR:
1123 ifmam = (struct ifma_msghdr *)rtm;
1124 mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1125 if (addrs[RTAX_IFA] == NULL ||
1126 addrs[RTAX_IFA]->sa_family != AF_LINK)
1127 break;
1128 sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1129 if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1130 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) != NULL)
1131 mib_rcvaddr_delete(rcv);
1132 break;
1133
1134 case RTM_IFINFO:
1135 ifm = (struct if_msghdr *)(void *)rtm;
1136 mib_extract_addrs(ifm->ifm_addrs, (u_char *)(ifm + 1), addrs);
1137 if ((ifp = mib_find_if_sys(ifm->ifm_index)) == NULL)
1138 break;
1139 if (addrs[RTAX_IFP] != NULL &&
1140 addrs[RTAX_IFP]->sa_family == AF_LINK) {
1141 sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFP];
1142 ptr = sdl->sdl_data + sdl->sdl_nlen;
1143 get_physaddr(ifp, sdl, ptr);
1144 }
1145 (void)mib_fetch_ifmib(ifp);
1146 break;
1147
1148 #ifdef RTM_IFANNOUNCE
1149 case RTM_IFANNOUNCE:
1150 ifan = (struct if_announcemsghdr *)rtm;
1151 ifp = mib_find_if_sys(ifan->ifan_index);
1152
1153 switch (ifan->ifan_what) {
1154
1155 case IFAN_ARRIVAL:
1156 if (ifp == NULL && (ifp = mibif_create(ifan->ifan_index,
1157 ifan->ifan_name)) != NULL) {
1158 (void)mib_fetch_ifmib(ifp);
1159 check_llbcast(ifp);
1160 notify_newif(ifp);
1161 }
1162 break;
1163
1164 case IFAN_DEPARTURE:
1165 if (ifp != NULL)
1166 mibif_free(ifp);
1167 break;
1168 }
1169 break;
1170 #endif
1171 case RTM_GET:
1172 case RTM_ADD:
1173 mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1174 if (rtm->rtm_flags & RTF_LLINFO) {
1175 if (addrs[RTAX_DST] == NULL ||
1176 addrs[RTAX_GATEWAY] == NULL ||
1177 addrs[RTAX_DST]->sa_family != AF_INET ||
1178 addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
1179 break;
1180 process_arp(rtm,
1181 (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
1182 (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
1183 } else {
1184 if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1185 mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1186 addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1187 }
1188 break;
1189
1190 case RTM_DELETE:
1191 mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1192
1193 if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1194 mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1195 addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1196 break;
1197 }
1198 }
1199
1200 /*
1201 * send a routing message
1202 */
1203 void
mib_send_rtmsg(struct rt_msghdr * rtm,struct sockaddr * gw,struct sockaddr * dst,struct sockaddr * mask)1204 mib_send_rtmsg(struct rt_msghdr *rtm, struct sockaddr *gw,
1205 struct sockaddr *dst, struct sockaddr *mask)
1206 {
1207 size_t len;
1208 struct rt_msghdr *msg;
1209 char *cp;
1210 ssize_t sent;
1211
1212 len = sizeof(*rtm) + SA_SIZE(gw) + SA_SIZE(dst) + SA_SIZE(mask);
1213 if ((msg = malloc(len)) == NULL) {
1214 syslog(LOG_ERR, "%s: %m", __func__);
1215 return;
1216 }
1217 cp = (char *)(msg + 1);
1218
1219 memset(msg, 0, sizeof(*msg));
1220 msg->rtm_flags = 0;
1221 msg->rtm_version = RTM_VERSION;
1222 msg->rtm_addrs = RTA_DST | RTA_GATEWAY;
1223
1224 memcpy(cp, dst, SA_SIZE(dst));
1225 cp += SA_SIZE(dst);
1226 memcpy(cp, gw, SA_SIZE(gw));
1227 cp += SA_SIZE(gw);
1228 if (mask != NULL) {
1229 memcpy(cp, mask, SA_SIZE(mask));
1230 cp += SA_SIZE(mask);
1231 msg->rtm_addrs |= RTA_NETMASK;
1232 }
1233 msg->rtm_msglen = cp - (char *)msg;
1234 msg->rtm_type = RTM_GET;
1235 if ((sent = write(route, msg, msg->rtm_msglen)) == -1) {
1236 syslog(LOG_ERR, "%s: write: %m", __func__);
1237 free(msg);
1238 return;
1239 }
1240 if (sent != msg->rtm_msglen) {
1241 syslog(LOG_ERR, "%s: short write", __func__);
1242 free(msg);
1243 return;
1244 }
1245 free(msg);
1246 }
1247
1248 /*
1249 * Fetch the routing table via sysctl
1250 */
1251 u_char *
mib_fetch_rtab(int af,int info,int arg,size_t * lenp)1252 mib_fetch_rtab(int af, int info, int arg, size_t *lenp)
1253 {
1254 int name[6];
1255 u_char *buf, *newbuf;
1256
1257 name[0] = CTL_NET;
1258 name[1] = PF_ROUTE;
1259 name[2] = 0;
1260 name[3] = af;
1261 name[4] = info;
1262 name[5] = arg;
1263
1264 *lenp = 0;
1265
1266 /* initial estimate */
1267 if (sysctl(name, nitems(name), NULL, lenp, NULL, 0) == -1) {
1268 syslog(LOG_ERR, "sysctl estimate (%d,%d,%d,%d,%d,%d): %m",
1269 name[0], name[1], name[2], name[3], name[4], name[5]);
1270 return (NULL);
1271 }
1272 if (*lenp == 0)
1273 return (NULL);
1274
1275 buf = NULL;
1276 for (;;) {
1277 if ((newbuf = realloc(buf, *lenp)) == NULL) {
1278 syslog(LOG_ERR, "sysctl buffer: %m");
1279 free(buf);
1280 return (NULL);
1281 }
1282 buf = newbuf;
1283
1284 if (sysctl(name, nitems(name), buf, lenp, NULL, 0) == 0)
1285 break;
1286
1287 if (errno != ENOMEM) {
1288 syslog(LOG_ERR, "sysctl get: %m");
1289 free(buf);
1290 return (NULL);
1291 }
1292 *lenp += *lenp / 8 + 1;
1293 }
1294
1295 return (buf);
1296 }
1297
1298 /*
1299 * Update the following info: interface, interface addresses, interface
1300 * receive addresses, arp-table.
1301 * This does not change the interface list itself.
1302 */
1303 static void
update_ifa_info(void)1304 update_ifa_info(void)
1305 {
1306 u_char *buf, *next;
1307 struct rt_msghdr *rtm;
1308 struct mibifa *ifa, *ifa1;
1309 struct mibrcvaddr *rcv, *rcv1;
1310 size_t needed;
1311 static const int infos[][3] = {
1312 { 0, NET_RT_IFLIST, 0 },
1313 #ifdef NET_RT_IFMALIST
1314 { AF_LINK, NET_RT_IFMALIST, 0 },
1315 #endif
1316 };
1317 u_int i;
1318
1319 TAILQ_FOREACH(ifa, &mibifa_list, link)
1320 ifa->flags &= ~MIBIFA_FOUND;
1321 TAILQ_FOREACH(rcv, &mibrcvaddr_list, link)
1322 rcv->flags &= ~MIBRCVADDR_FOUND;
1323
1324 for (i = 0; i < sizeof(infos) / sizeof(infos[0]); i++) {
1325 if ((buf = mib_fetch_rtab(infos[i][0], infos[i][1], infos[i][2],
1326 &needed)) == NULL)
1327 continue;
1328
1329 next = buf;
1330 while (next < buf + needed) {
1331 rtm = (struct rt_msghdr *)(void *)next;
1332 next += rtm->rtm_msglen;
1333 handle_rtmsg(rtm);
1334 }
1335 free(buf);
1336 }
1337
1338 /*
1339 * Purge the address list of unused entries. These may happen for
1340 * interface aliases that are on the same subnet. We don't receive
1341 * routing socket messages for them.
1342 */
1343 ifa = TAILQ_FIRST(&mibifa_list);
1344 while (ifa != NULL) {
1345 ifa1 = TAILQ_NEXT(ifa, link);
1346 if (!(ifa->flags & MIBIFA_FOUND))
1347 destroy_ifa(ifa);
1348 ifa = ifa1;
1349 }
1350
1351 rcv = TAILQ_FIRST(&mibrcvaddr_list);
1352 while (rcv != NULL) {
1353 rcv1 = TAILQ_NEXT(rcv, link);
1354 if (!(rcv->flags & (MIBRCVADDR_FOUND | MIBRCVADDR_BCAST |
1355 MIBRCVADDR_HW)))
1356 mib_rcvaddr_delete(rcv);
1357 rcv = rcv1;
1358 }
1359 }
1360
1361 /*
1362 * Update arp table
1363 */
1364 void
mib_arp_update(void)1365 mib_arp_update(void)
1366 {
1367 struct mibarp *at, *at1;
1368 size_t needed;
1369 u_char *buf, *next;
1370 struct rt_msghdr *rtm;
1371
1372 if (in_update_arp)
1373 return; /* Aaargh */
1374 in_update_arp = 1;
1375
1376 TAILQ_FOREACH(at, &mibarp_list, link)
1377 at->flags &= ~MIBARP_FOUND;
1378
1379 if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, 0, &needed)) == NULL) {
1380 in_update_arp = 0;
1381 return;
1382 }
1383
1384 next = buf;
1385 while (next < buf + needed) {
1386 rtm = (struct rt_msghdr *)(void *)next;
1387 next += rtm->rtm_msglen;
1388 handle_rtmsg(rtm);
1389 }
1390 free(buf);
1391
1392 at = TAILQ_FIRST(&mibarp_list);
1393 while (at != NULL) {
1394 at1 = TAILQ_NEXT(at, link);
1395 if (!(at->flags & MIBARP_FOUND))
1396 mib_arp_delete(at);
1397 at = at1;
1398 }
1399 mibarpticks = get_ticks();
1400 in_update_arp = 0;
1401 }
1402
1403
1404 /*
1405 * Input on the routing socket.
1406 */
1407 static void
route_input(int fd,void * udata __unused)1408 route_input(int fd, void *udata __unused)
1409 {
1410 u_char buf[1024 * 16];
1411 ssize_t n;
1412 struct rt_msghdr *rtm;
1413
1414 if ((n = read(fd, buf, sizeof(buf))) == -1)
1415 err(1, "read(rt_socket)");
1416
1417 if (n == 0)
1418 errx(1, "EOF on rt_socket");
1419
1420 rtm = (struct rt_msghdr *)(void *)buf;
1421 if ((size_t)n != rtm->rtm_msglen)
1422 errx(1, "n=%zu, rtm_msglen=%u", (size_t)n, rtm->rtm_msglen);
1423
1424 handle_rtmsg(rtm);
1425 }
1426
1427 /*
1428 * execute and SIOCAIFADDR
1429 */
1430 static int
siocaifaddr(char * ifname,struct in_addr addr,struct in_addr mask,struct in_addr bcast)1431 siocaifaddr(char *ifname, struct in_addr addr, struct in_addr mask,
1432 struct in_addr bcast)
1433 {
1434 struct ifaliasreq addreq;
1435 struct sockaddr_in *sa;
1436
1437 memset(&addreq, 0, sizeof(addreq));
1438 strlcpy(addreq.ifra_name, ifname, sizeof(addreq.ifra_name));
1439
1440 sa = (struct sockaddr_in *)(void *)&addreq.ifra_addr;
1441 sa->sin_family = AF_INET;
1442 sa->sin_len = sizeof(*sa);
1443 sa->sin_addr = addr;
1444
1445 sa = (struct sockaddr_in *)(void *)&addreq.ifra_mask;
1446 sa->sin_family = AF_INET;
1447 sa->sin_len = sizeof(*sa);
1448 sa->sin_addr = mask;
1449
1450 sa = (struct sockaddr_in *)(void *)&addreq.ifra_broadaddr;
1451 sa->sin_family = AF_INET;
1452 sa->sin_len = sizeof(*sa);
1453 sa->sin_addr = bcast;
1454
1455 return (ioctl(mib_netsock, SIOCAIFADDR, &addreq));
1456 }
1457
1458 /*
1459 * Exececute a SIOCDIFADDR
1460 */
1461 static int
siocdifaddr(const char * ifname,struct in_addr addr)1462 siocdifaddr(const char *ifname, struct in_addr addr)
1463 {
1464 struct ifreq delreq;
1465 struct sockaddr_in *sa;
1466
1467 memset(&delreq, 0, sizeof(delreq));
1468 strlcpy(delreq.ifr_name, ifname, sizeof(delreq.ifr_name));
1469 sa = (struct sockaddr_in *)(void *)&delreq.ifr_addr;
1470 sa->sin_family = AF_INET;
1471 sa->sin_len = sizeof(*sa);
1472 sa->sin_addr = addr;
1473
1474 return (ioctl(mib_netsock, SIOCDIFADDR, &delreq));
1475 }
1476
1477 /*
1478 * Verify an interface address without fetching the entire list
1479 */
1480 static int
verify_ifa(const char * name,struct mibifa * ifa)1481 verify_ifa(const char *name, struct mibifa *ifa)
1482 {
1483 struct ifreq req;
1484 struct sockaddr_in *sa;
1485
1486 memset(&req, 0, sizeof(req));
1487 strlcpy(req.ifr_name, name, sizeof(req.ifr_name));
1488 sa = (struct sockaddr_in *)(void *)&req.ifr_addr;
1489 sa->sin_family = AF_INET;
1490 sa->sin_len = sizeof(*sa);
1491 sa->sin_addr = ifa->inaddr;
1492
1493 if (ioctl(mib_netsock, SIOCGIFADDR, &req) == -1)
1494 return (-1);
1495 if (ifa->inaddr.s_addr != sa->sin_addr.s_addr) {
1496 syslog(LOG_ERR, "%s: address mismatch", __func__);
1497 return (-1);
1498 }
1499
1500 if (ioctl(mib_netsock, SIOCGIFNETMASK, &req) == -1)
1501 return (-1);
1502 if (ifa->inmask.s_addr != sa->sin_addr.s_addr) {
1503 syslog(LOG_ERR, "%s: netmask mismatch", __func__);
1504 return (-1);
1505 }
1506 return (0);
1507 }
1508
1509 /*
1510 * Restore a deleted interface address. Don't wait for the routing socket
1511 * to update us.
1512 */
1513 void
mib_undestroy_ifa(struct mibifa * ifa)1514 mib_undestroy_ifa(struct mibifa *ifa)
1515 {
1516 struct mibif *ifp;
1517
1518 if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
1519 /* keep it destroyed */
1520 return;
1521
1522 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast))
1523 /* keep it destroyed */
1524 return;
1525
1526 ifa->flags &= ~MIBIFA_DESTROYED;
1527 }
1528
1529 /*
1530 * Destroy an interface address
1531 */
1532 int
mib_destroy_ifa(struct mibifa * ifa)1533 mib_destroy_ifa(struct mibifa *ifa)
1534 {
1535 struct mibif *ifp;
1536
1537 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1538 /* ups. */
1539 mib_iflist_bad = 1;
1540 return (-1);
1541 }
1542 if (siocdifaddr(ifp->name, ifa->inaddr)) {
1543 /* ups. */
1544 syslog(LOG_ERR, "SIOCDIFADDR: %m");
1545 mib_iflist_bad = 1;
1546 return (-1);
1547 }
1548 ifa->flags |= MIBIFA_DESTROYED;
1549 return (0);
1550 }
1551
1552 /*
1553 * Rollback the modification of an address. Don't bother to wait for
1554 * the routing socket.
1555 */
1556 void
mib_unmodify_ifa(struct mibifa * ifa)1557 mib_unmodify_ifa(struct mibifa *ifa)
1558 {
1559 struct mibif *ifp;
1560
1561 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1562 /* ups. */
1563 mib_iflist_bad = 1;
1564 return;
1565 }
1566
1567 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1568 /* ups. */
1569 mib_iflist_bad = 1;
1570 return;
1571 }
1572 }
1573
1574 /*
1575 * Modify an IFA.
1576 */
1577 int
mib_modify_ifa(struct mibifa * ifa)1578 mib_modify_ifa(struct mibifa *ifa)
1579 {
1580 struct mibif *ifp;
1581
1582 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1583 /* ups. */
1584 mib_iflist_bad = 1;
1585 return (-1);
1586 }
1587
1588 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1589 /* ups. */
1590 mib_iflist_bad = 1;
1591 return (-1);
1592 }
1593
1594 if (verify_ifa(ifp->name, ifa)) {
1595 /* ups. */
1596 mib_iflist_bad = 1;
1597 return (-1);
1598 }
1599
1600 return (0);
1601 }
1602
1603 /*
1604 * Destroy a freshly created interface address. Don't bother to wait for
1605 * the routing socket.
1606 */
1607 void
mib_uncreate_ifa(struct mibifa * ifa)1608 mib_uncreate_ifa(struct mibifa *ifa)
1609 {
1610 struct mibif *ifp;
1611
1612 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1613 /* ups. */
1614 mib_iflist_bad = 1;
1615 return;
1616 }
1617 if (siocdifaddr(ifp->name, ifa->inaddr)) {
1618 /* ups. */
1619 mib_iflist_bad = 1;
1620 return;
1621 }
1622
1623 destroy_ifa(ifa);
1624 }
1625
1626 /*
1627 * Create a new ifa and verify it
1628 */
1629 struct mibifa *
mib_create_ifa(u_int ifindex,struct in_addr addr,struct in_addr mask,struct in_addr bcast)1630 mib_create_ifa(u_int ifindex, struct in_addr addr, struct in_addr mask,
1631 struct in_addr bcast)
1632 {
1633 struct mibif *ifp;
1634 struct mibifa *ifa;
1635
1636 if ((ifp = mib_find_if(ifindex)) == NULL)
1637 return (NULL);
1638 if ((ifa = alloc_ifa(ifindex, addr)) == NULL)
1639 return (NULL);
1640 ifa->inmask = mask;
1641 ifa->inbcast = bcast;
1642
1643 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1644 syslog(LOG_ERR, "%s: %m", __func__);
1645 destroy_ifa(ifa);
1646 return (NULL);
1647 }
1648 if (verify_ifa(ifp->name, ifa)) {
1649 destroy_ifa(ifa);
1650 return (NULL);
1651 }
1652 return (ifa);
1653 }
1654
1655 /*
1656 * Get all cloning interfaces and make them dynamic.
1657 * Hah! Whe should probably do this on a periodic basis (XXX).
1658 */
1659 static void
get_cloners(void)1660 get_cloners(void)
1661 {
1662 struct if_clonereq req;
1663 char *buf, *cp;
1664 int i;
1665
1666 memset(&req, 0, sizeof(req));
1667 if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1668 syslog(LOG_ERR, "get cloners: %m");
1669 return;
1670 }
1671 if ((buf = malloc(req.ifcr_total * IFNAMSIZ)) == NULL) {
1672 syslog(LOG_ERR, "%m");
1673 return;
1674 }
1675 req.ifcr_count = req.ifcr_total;
1676 req.ifcr_buffer = buf;
1677 if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1678 syslog(LOG_ERR, "get cloners: %m");
1679 free(buf);
1680 return;
1681 }
1682 for (cp = buf, i = 0; i < req.ifcr_total; i++, cp += IFNAMSIZ)
1683 mib_if_set_dyn(cp);
1684 free(buf);
1685 }
1686
1687 /*
1688 * Idle function
1689 */
1690 static void
mibII_idle(void * arg __unused)1691 mibII_idle(void *arg __unused)
1692 {
1693 struct mibifa *ifa;
1694
1695 if (mib_iflist_bad) {
1696 TAILQ_FOREACH(ifa, &mibifa_list, link)
1697 ifa->flags &= ~MIBIFA_DESTROYED;
1698
1699 /* assume, that all cloning interfaces are dynamic */
1700 get_cloners();
1701
1702 mib_refresh_iflist();
1703 update_ifa_info();
1704 mib_arp_update();
1705 mib_iflist_bad = 0;
1706 }
1707
1708 mib_arp_update();
1709 }
1710
1711
1712 /*
1713 * Start the module
1714 */
1715 static void
mibII_start(void)1716 mibII_start(void)
1717 {
1718 if ((route_fd = fd_select(route, route_input, NULL, module)) == NULL) {
1719 syslog(LOG_ERR, "fd_select(route): %m");
1720 return;
1721 }
1722 mib_refresh_iflist();
1723 update_ifa_info();
1724 mib_arp_update();
1725 (void)mib_fetch_route();
1726 mib_iftable_last_change = 0;
1727 mib_ifstack_last_change = 0;
1728
1729 ifmib_reg = or_register(&oid_ifMIB,
1730 "The MIB module to describe generic objects for network interface"
1731 " sub-layers.", module);
1732
1733 ipmib_reg = or_register(&oid_ipMIB,
1734 "The MIB module for managing IP and ICMP implementations, but "
1735 "excluding their management of IP routes.", module);
1736
1737 tcpmib_reg = or_register(&oid_tcpMIB,
1738 "The MIB module for managing TCP implementations.", module);
1739
1740 udpmib_reg = or_register(&oid_udpMIB,
1741 "The MIB module for managing UDP implementations.", module);
1742
1743 ipForward_reg = or_register(&oid_ipForward,
1744 "The MIB module for the display of CIDR multipath IP Routes.",
1745 module);
1746
1747 mibII_poll_timer = NULL;
1748 mibII_poll_ticks = MIBII_POLL_TICKS;
1749 mibif_restart_mibII_poll_timer();
1750 }
1751
1752 /*
1753 * Initialize the module
1754 */
1755 static int
mibII_init(struct lmodule * mod,int argc __unused,char * argv[]__unused)1756 mibII_init(struct lmodule *mod, int argc __unused, char *argv[] __unused)
1757 {
1758 size_t len;
1759
1760 module = mod;
1761
1762 len = sizeof(clockinfo);
1763 if (sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0) == -1) {
1764 syslog(LOG_ERR, "kern.clockrate: %m");
1765 return (-1);
1766 }
1767 if (len != sizeof(clockinfo)) {
1768 syslog(LOG_ERR, "kern.clockrate: wrong size");
1769 return (-1);
1770 }
1771
1772 if ((route = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) == -1) {
1773 syslog(LOG_ERR, "PF_ROUTE: %m");
1774 return (-1);
1775 }
1776
1777 if ((mib_netsock = socket(PF_INET, SOCK_DGRAM, 0)) == -1) {
1778 syslog(LOG_ERR, "PF_INET: %m");
1779 (void)close(route);
1780 return (-1);
1781 }
1782 (void)shutdown(mib_netsock, SHUT_RDWR);
1783
1784 /* assume, that all cloning interfaces are dynamic */
1785 get_cloners();
1786
1787 return (0);
1788 }
1789
1790 static int
mibII_fini(void)1791 mibII_fini(void)
1792 {
1793 if (mibII_poll_timer != NULL ) {
1794 timer_stop(mibII_poll_timer);
1795 mibII_poll_timer = NULL;
1796 }
1797
1798 if (route_fd != NULL)
1799 fd_deselect(route_fd);
1800 if (route != -1)
1801 (void)close(route);
1802 if (mib_netsock != -1)
1803 (void)close(mib_netsock);
1804 /* XXX free memory */
1805
1806 or_unregister(ipForward_reg);
1807 or_unregister(udpmib_reg);
1808 or_unregister(tcpmib_reg);
1809 or_unregister(ipmib_reg);
1810 or_unregister(ifmib_reg);
1811
1812 return (0);
1813 }
1814
1815 static void
mibII_loading(const struct lmodule * mod,int loaded)1816 mibII_loading(const struct lmodule *mod, int loaded)
1817 {
1818 struct mibif *ifp;
1819
1820 if (loaded == 1)
1821 return;
1822
1823 TAILQ_FOREACH(ifp, &mibif_list, link)
1824 if (ifp->xnotify_mod == mod) {
1825 ifp->xnotify_mod = NULL;
1826 ifp->xnotify_data = NULL;
1827 ifp->xnotify = NULL;
1828 }
1829
1830 mib_unregister_newif(mod);
1831 }
1832
1833 extern const struct snmp_module config;
1834 const struct snmp_module config = {
1835 "This module implements the interface and ip groups.",
1836 mibII_init,
1837 mibII_fini,
1838 NULL, /* idle */
1839 NULL, /* dump */
1840 NULL, /* config */
1841 mibII_start,
1842 NULL,
1843 mibII_ctree,
1844 mibII_CTREE_SIZE,
1845 mibII_loading
1846 };
1847
1848 /*
1849 * Should have a list of these attached to each interface.
1850 */
1851 void *
mibif_notify(struct mibif * ifp,const struct lmodule * mod,mibif_notify_f func,void * data)1852 mibif_notify(struct mibif *ifp, const struct lmodule *mod,
1853 mibif_notify_f func, void *data)
1854 {
1855 ifp->xnotify = func;
1856 ifp->xnotify_data = data;
1857 ifp->xnotify_mod = mod;
1858
1859 return (ifp);
1860 }
1861
1862 void
mibif_unnotify(void * arg)1863 mibif_unnotify(void *arg)
1864 {
1865 struct mibif *ifp = arg;
1866
1867 ifp->xnotify = NULL;
1868 ifp->xnotify_data = NULL;
1869 ifp->xnotify_mod = NULL;
1870 }
1871