1 /*
2 * Copyright (c) 2001-2003
3 * Fraunhofer Institute for Open Communication Systems (FhG Fokus).
4 * All rights reserved.
5 *
6 * Author: Harti Brandt <[email protected]>
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 * 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
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 unsigned 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 /*
524 * Find sysctl mib for net.ifdescr_maxlen (one time).
525 * kmib[0] == -1 at first call to mib_fetch_ifmib().
526 * Then kmib[0] > 0 if we found sysctl mib for net.ifdescr_maxlen.
527 * Else, kmib[0] == 0 (unexpected error from a kernel).
528 */
529 if (kmib[0] < 0 &&
530 sysctlnametomib("net.ifdescr_maxlen", kmib, &kmiblen) < 0) {
531 kmib[0] = 0;
532 syslog(LOG_WARNING, "sysctlnametomib net.ifdescr_maxlen: %m");
533 }
534
535 /*
536 * Fetch net.ifdescr_maxlen value every time to catch up with changes.
537 */
538 len = sizeof(alias_maxlen);
539 if (kmib[0] > 0 && sysctl(kmib, 2, &alias_maxlen, &len, NULL, 0) < 0) {
540 /* unexpected error from the kernel, use default value */
541 alias_maxlen = MIBIF_ALIAS_SIZE_MAX;
542 syslog(LOG_WARNING, "sysctl net.ifdescr_maxlen: %m");
543 }
544
545 /*
546 * Kernel limit might be decreased after interfaces got
547 * their descriptions assigned. Try to obtain them anyway.
548 */
549 if (alias_maxlen == 0)
550 alias_maxlen = MIBIF_ALIAS_SIZE_MAX;
551
552 /*
553 * Allocate maximum memory for a buffer and later reallocate
554 * to free extra memory.
555 */
556 if ((ifp->alias = malloc(alias_maxlen)) == NULL) {
557 syslog(LOG_WARNING, "malloc(%d) failed: %m", (int)alias_maxlen);
558 goto fin;
559 }
560
561 strlcpy(irr.ifr_name, ifp->name, sizeof(irr.ifr_name));
562 irr.ifr_buffer.buffer = ifp->alias;
563 irr.ifr_buffer.length = alias_maxlen;
564 if (ioctl(mib_netsock, SIOCGIFDESCR, &irr) == -1) {
565 free(ifp->alias);
566 ifp->alias = NULL;
567 if (errno != ENOMSG)
568 syslog(LOG_WARNING, "SIOCGIFDESCR (%s): %m", ifp->name);
569 } else if (irr.ifr_buffer.buffer == NULL) {
570 free(ifp->alias);
571 ifp->alias = NULL;
572 syslog(LOG_WARNING, "SIOCGIFDESCR (%s): too long (%zu)",
573 ifp->name, irr.ifr_buffer.length);
574 } else {
575 ifp->alias_size = strnlen(ifp->alias, alias_maxlen) + 1;
576
577 if (ifp->alias_size > MIBIF_ALIAS_SIZE)
578 ifp->alias_size = MIBIF_ALIAS_SIZE;
579
580 if (ifp->alias_size < alias_maxlen)
581 ifp->alias = realloc(ifp->alias, ifp->alias_size);
582 }
583
584 fin:
585 ifp->mibtick = get_ticks();
586 return (0);
587 }
588
589 /* find first/next address for a given interface */
590 struct mibifa *
mib_first_ififa(const struct mibif * ifp)591 mib_first_ififa(const struct mibif *ifp)
592 {
593 struct mibifa *ifa;
594
595 TAILQ_FOREACH(ifa, &mibifa_list, link)
596 if (ifp->index == ifa->ifindex)
597 return (ifa);
598 return (NULL);
599 }
600
601 struct mibifa *
mib_next_ififa(struct mibifa * ifa0)602 mib_next_ififa(struct mibifa *ifa0)
603 {
604 struct mibifa *ifa;
605
606 ifa = ifa0;
607 while ((ifa = TAILQ_NEXT(ifa, link)) != NULL)
608 if (ifa->ifindex == ifa0->ifindex)
609 return (ifa);
610 return (NULL);
611 }
612
613 /*
614 * Allocate a new IFA
615 */
616 static struct mibifa *
alloc_ifa(u_int ifindex,struct in_addr addr)617 alloc_ifa(u_int ifindex, struct in_addr addr)
618 {
619 struct mibifa *ifa;
620 uint32_t ha;
621
622 if ((ifa = malloc(sizeof(struct mibifa))) == NULL) {
623 syslog(LOG_ERR, "ifa: %m");
624 return (NULL);
625 }
626 ifa->inaddr = addr;
627 ifa->ifindex = ifindex;
628
629 ha = ntohl(ifa->inaddr.s_addr);
630 ifa->index.len = 4;
631 ifa->index.subs[0] = (ha >> 24) & 0xff;
632 ifa->index.subs[1] = (ha >> 16) & 0xff;
633 ifa->index.subs[2] = (ha >> 8) & 0xff;
634 ifa->index.subs[3] = (ha >> 0) & 0xff;
635
636 ifa->flags = 0;
637 ifa->inbcast.s_addr = 0;
638 ifa->inmask.s_addr = 0xffffffff;
639
640 INSERT_OBJECT_OID(ifa, &mibifa_list);
641
642 return (ifa);
643 }
644
645 /*
646 * Delete an interface address
647 */
648 static void
destroy_ifa(struct mibifa * ifa)649 destroy_ifa(struct mibifa *ifa)
650 {
651 TAILQ_REMOVE(&mibifa_list, ifa, link);
652 free(ifa);
653 }
654
655
656 /*
657 * Helper routine to extract the sockaddr structures from a routing
658 * socket message.
659 */
660 void
mib_extract_addrs(int addrs,u_char * info,struct sockaddr ** out)661 mib_extract_addrs(int addrs, u_char *info, struct sockaddr **out)
662 {
663 u_int i;
664
665 for (i = 0; i < RTAX_MAX; i++) {
666 if ((addrs & (1 << i)) != 0) {
667 *out = (struct sockaddr *)(void *)info;
668 info += roundup((*out)->sa_len, sizeof(long));
669 } else
670 *out = NULL;
671 out++;
672 }
673 }
674
675 /*
676 * save the phys address of an interface. Handle receive address entries here.
677 */
678 static void
get_physaddr(struct mibif * ifp,struct sockaddr_dl * sdl,u_char * ptr)679 get_physaddr(struct mibif *ifp, struct sockaddr_dl *sdl, u_char *ptr)
680 {
681 u_char *np;
682 struct mibrcvaddr *rcv;
683
684 if (sdl->sdl_alen == 0) {
685 /* no address */
686 if (ifp->physaddrlen != 0) {
687 if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
688 ifp->physaddrlen)) != NULL)
689 mib_rcvaddr_delete(rcv);
690 free(ifp->physaddr);
691 ifp->physaddr = NULL;
692 ifp->physaddrlen = 0;
693 }
694 return;
695 }
696
697 if (ifp->physaddrlen != sdl->sdl_alen) {
698 /* length changed */
699 if (ifp->physaddrlen) {
700 /* delete olf receive address */
701 if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
702 ifp->physaddrlen)) != NULL)
703 mib_rcvaddr_delete(rcv);
704 }
705 if ((np = realloc(ifp->physaddr, sdl->sdl_alen)) == NULL) {
706 free(ifp->physaddr);
707 ifp->physaddr = NULL;
708 ifp->physaddrlen = 0;
709 return;
710 }
711 ifp->physaddr = np;
712 ifp->physaddrlen = sdl->sdl_alen;
713
714 } else if (memcmp(ifp->physaddr, ptr, ifp->physaddrlen) == 0) {
715 /* no change */
716 return;
717
718 } else {
719 /* address changed */
720
721 /* delete olf receive address */
722 if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
723 ifp->physaddrlen)) != NULL)
724 mib_rcvaddr_delete(rcv);
725 }
726
727 memcpy(ifp->physaddr, ptr, ifp->physaddrlen);
728
729 /* make new receive address */
730 if ((rcv = mib_rcvaddr_create(ifp, ifp->physaddr, ifp->physaddrlen)) != NULL)
731 rcv->flags |= MIBRCVADDR_HW;
732 }
733
734 /*
735 * Free an interface
736 */
737 static void
mibif_free(struct mibif * ifp)738 mibif_free(struct mibif *ifp)
739 {
740 struct mibif *ifp1;
741 struct mibindexmap *map;
742 struct mibifa *ifa, *ifa1;
743 struct mibrcvaddr *rcv, *rcv1;
744 struct mibarp *at, *at1;
745
746 if (ifp->xnotify != NULL)
747 (*ifp->xnotify)(ifp, MIBIF_NOTIFY_DESTROY, ifp->xnotify_data);
748
749 (void)mib_ifstack_delete(ifp, NULL);
750 (void)mib_ifstack_delete(NULL, ifp);
751
752 TAILQ_REMOVE(&mibif_list, ifp, link);
753
754 /* if this was the fastest interface - recompute this */
755 if (ifp->mib.ifmd_data.ifi_baudrate == mibif_maxspeed) {
756 mibif_maxspeed = ifp->mib.ifmd_data.ifi_baudrate;
757 TAILQ_FOREACH(ifp1, &mibif_list, link)
758 if (ifp1->mib.ifmd_data.ifi_baudrate > mibif_maxspeed)
759 mibif_maxspeed =
760 ifp1->mib.ifmd_data.ifi_baudrate;
761 mibif_reset_hc_timer();
762 }
763
764 if (ifp->alias != NULL) {
765 free(ifp->alias);
766 ifp->alias = NULL;
767 }
768 free(ifp->private);
769 ifp->private = NULL;
770 free(ifp->physaddr);
771 ifp->physaddr = NULL;
772 free(ifp->specmib);
773 ifp->specmib = NULL;
774
775 STAILQ_FOREACH(map, &mibindexmap_list, link)
776 if (map->mibif == ifp) {
777 map->mibif = NULL;
778 break;
779 }
780
781 /* purge interface addresses */
782 ifa = TAILQ_FIRST(&mibifa_list);
783 while (ifa != NULL) {
784 ifa1 = TAILQ_NEXT(ifa, link);
785 if (ifa->ifindex == ifp->index)
786 destroy_ifa(ifa);
787 ifa = ifa1;
788 }
789
790 /* purge receive addresses */
791 rcv = TAILQ_FIRST(&mibrcvaddr_list);
792 while (rcv != NULL) {
793 rcv1 = TAILQ_NEXT(rcv, link);
794 if (rcv->ifindex == ifp->index)
795 mib_rcvaddr_delete(rcv);
796 rcv = rcv1;
797 }
798
799 /* purge ARP entries */
800 at = TAILQ_FIRST(&mibarp_list);
801 while (at != NULL) {
802 at1 = TAILQ_NEXT(at, link);
803 if (at->index.subs[0] == ifp->index)
804 mib_arp_delete(at);
805 at = at1;
806 }
807
808 free(ifp);
809 ifp = NULL;
810 mib_if_number--;
811 mib_iftable_last_change = this_tick;
812 }
813
814 /*
815 * Create a new interface
816 */
817 static struct mibif *
mibif_create(u_int sysindex,const char * name)818 mibif_create(u_int sysindex, const char *name)
819 {
820 struct mibif *ifp;
821 struct mibindexmap *map;
822
823 if ((ifp = malloc(sizeof(*ifp))) == NULL) {
824 syslog(LOG_WARNING, "%s: %m", __func__);
825 return (NULL);
826 }
827 memset(ifp, 0, sizeof(*ifp));
828 if ((ifp->private = malloc(sizeof(struct mibif_private))) == NULL) {
829 syslog(LOG_WARNING, "%s: %m", __func__);
830 free(ifp);
831 return (NULL);
832 }
833 memset(ifp->private, 0, sizeof(struct mibif_private));
834
835 ifp->sysindex = sysindex;
836 strlcpy(ifp->name, name, sizeof(ifp->name));
837 strlcpy(ifp->descr, name, sizeof(ifp->descr));
838 ifp->spec_oid = oid_zeroDotZero;
839
840 map = NULL;
841 if (!mib_if_is_dyn(ifp->name)) {
842 /* non-dynamic. look whether we know the interface */
843 STAILQ_FOREACH(map, &mibindexmap_list, link)
844 if (strcmp(map->name, ifp->name) == 0) {
845 ifp->index = map->ifindex;
846 map->mibif = ifp;
847 break;
848 }
849 /* assume it has a connector if it is not dynamic */
850 ifp->has_connector = 1;
851 ifp->trap_enable = 1;
852 }
853 if (map == NULL) {
854 /* new interface - get new index */
855 if (next_if_index > 0x7fffffff)
856 errx(1, "ifindex wrap");
857
858 if ((map = malloc(sizeof(*map))) == NULL) {
859 syslog(LOG_ERR, "ifmap: %m");
860 free(ifp);
861 return (NULL);
862 }
863 map->ifindex = next_if_index++;
864 map->sysindex = ifp->sysindex;
865 strcpy(map->name, ifp->name);
866 map->mibif = ifp;
867 STAILQ_INSERT_TAIL(&mibindexmap_list, map, link);
868 } else {
869 /* re-instantiate. Introduce a counter discontinuity */
870 ifp->counter_disc = get_ticks();
871 }
872 ifp->index = map->ifindex;
873 ifp->mib.ifmd_data.ifi_link_state = LINK_STATE_UNKNOWN;
874
875 INSERT_OBJECT_INT(ifp, &mibif_list);
876 mib_if_number++;
877 mib_iftable_last_change = this_tick;
878
879 /* instantiate default ifStack entries */
880 (void)mib_ifstack_create(ifp, NULL);
881 (void)mib_ifstack_create(NULL, ifp);
882
883 return (ifp);
884 }
885
886 /*
887 * Inform all interested parties about a new interface
888 */
889 static void
notify_newif(struct mibif * ifp)890 notify_newif(struct mibif *ifp)
891 {
892 struct newifreg *reg;
893
894 TAILQ_FOREACH(reg, &newifreg_list, link)
895 if ((*reg->func)(ifp))
896 return;
897 }
898
899 /*
900 * This is called for new interfaces after we have fetched the interface
901 * MIB. If this is a broadcast interface try to guess the broadcast address
902 * depending on the interface type.
903 */
904 static void
check_llbcast(struct mibif * ifp)905 check_llbcast(struct mibif *ifp)
906 {
907 static u_char ether_bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
908 struct mibrcvaddr *rcv;
909
910 if (!(ifp->mib.ifmd_flags & IFF_BROADCAST))
911 return;
912
913 switch (ifp->mib.ifmd_data.ifi_type) {
914
915 case IFT_ETHER:
916 case IFT_FDDI:
917 case IFT_ISO88025:
918 case IFT_L2VLAN:
919 if (mib_find_rcvaddr(ifp->index, ether_bcast, 6) == NULL &&
920 (rcv = mib_rcvaddr_create(ifp, ether_bcast, 6)) != NULL)
921 rcv->flags |= MIBRCVADDR_BCAST;
922 break;
923 }
924 }
925
926
927 /*
928 * Retrieve the current interface list from the system.
929 */
930 void
mib_refresh_iflist(void)931 mib_refresh_iflist(void)
932 {
933 struct mibif *ifp, *ifp1;
934 size_t len;
935 u_short idx;
936 int name[6];
937 int count;
938 struct ifmibdata mib;
939
940 TAILQ_FOREACH(ifp, &mibif_list, link)
941 ifp->flags &= ~MIBIF_FOUND;
942
943 len = sizeof(count);
944 if (sysctlbyname("net.link.generic.system.ifcount", &count, &len,
945 NULL, 0) == -1) {
946 syslog(LOG_ERR, "ifcount: %m");
947 return;
948 }
949 name[0] = CTL_NET;
950 name[1] = PF_LINK;
951 name[2] = NETLINK_GENERIC;
952 name[3] = IFMIB_IFDATA;
953 name[5] = IFDATA_GENERAL;
954 for (idx = 1; idx <= count; idx++) {
955 name[4] = idx;
956 len = sizeof(mib);
957 if (sysctl(name, nitems(name), &mib, &len, NULL, 0) == -1) {
958 if (errno == ENOENT)
959 continue;
960 syslog(LOG_ERR, "ifmib(%u): %m", idx);
961 return;
962 }
963 if ((ifp = mib_find_if_sys(idx)) != NULL) {
964 ifp->flags |= MIBIF_FOUND;
965 continue;
966 }
967 /* Unknown interface - create */
968 if ((ifp = mibif_create(idx, mib.ifmd_name)) != NULL) {
969 ifp->flags |= MIBIF_FOUND;
970 (void)mib_fetch_ifmib(ifp);
971 check_llbcast(ifp);
972 notify_newif(ifp);
973 }
974 }
975
976 /*
977 * Purge interfaces that disappeared
978 */
979 ifp = TAILQ_FIRST(&mibif_list);
980 while (ifp != NULL) {
981 ifp1 = TAILQ_NEXT(ifp, link);
982 if (!(ifp->flags & MIBIF_FOUND))
983 mibif_free(ifp);
984 ifp = ifp1;
985 }
986 }
987
988 /*
989 * Find an interface address
990 */
991 struct mibifa *
mib_find_ifa(struct in_addr addr)992 mib_find_ifa(struct in_addr addr)
993 {
994 struct mibifa *ifa;
995
996 TAILQ_FOREACH(ifa, &mibifa_list, link)
997 if (ifa->inaddr.s_addr == addr.s_addr)
998 return (ifa);
999 return (NULL);
1000 }
1001
1002 /*
1003 * Process a new ARP entry
1004 */
1005 static void
process_arp(const struct rt_msghdr * rtm,const struct sockaddr_dl * sdl,const struct sockaddr_in * sa)1006 process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl,
1007 const struct sockaddr_in *sa)
1008 {
1009 struct mibif *ifp;
1010 struct mibarp *at;
1011
1012 /* IP arp table entry */
1013 if (sdl->sdl_alen == 0)
1014 return;
1015 if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL)
1016 return;
1017 /* have a valid entry */
1018 if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL &&
1019 (at = mib_arp_create(ifp, sa->sin_addr,
1020 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
1021 return;
1022
1023 if (rtm->rtm_rmx.rmx_expire == 0)
1024 at->flags |= MIBARP_PERM;
1025 else
1026 at->flags &= ~MIBARP_PERM;
1027 at->flags |= MIBARP_FOUND;
1028 }
1029
1030 /*
1031 * Handle a routing socket message.
1032 */
1033 static void
handle_rtmsg(struct rt_msghdr * rtm)1034 handle_rtmsg(struct rt_msghdr *rtm)
1035 {
1036 struct sockaddr *addrs[RTAX_MAX];
1037 struct if_msghdr *ifm;
1038 struct ifa_msghdr ifam, *ifamp;
1039 struct ifma_msghdr *ifmam;
1040 #ifdef RTM_IFANNOUNCE
1041 struct if_announcemsghdr *ifan;
1042 #endif
1043 struct mibif *ifp;
1044 struct sockaddr_dl *sdl;
1045 struct sockaddr_in *sa;
1046 struct mibifa *ifa;
1047 struct mibrcvaddr *rcv;
1048 u_char *ptr;
1049
1050 if (rtm->rtm_version != RTM_VERSION) {
1051 syslog(LOG_ERR, "Bogus RTM version %u", rtm->rtm_version);
1052 return;
1053 }
1054
1055 switch (rtm->rtm_type) {
1056
1057 case RTM_NEWADDR:
1058 ifamp = (struct ifa_msghdr *)rtm;
1059 memcpy(&ifam, ifamp, sizeof(ifam));
1060 mib_extract_addrs(ifam.ifam_addrs, (u_char *)(ifamp + 1), addrs);
1061 if (addrs[RTAX_IFA] == NULL || addrs[RTAX_NETMASK] == NULL)
1062 break;
1063
1064 sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
1065 if ((ifa = mib_find_ifa(sa->sin_addr)) == NULL) {
1066 /* unknown address */
1067 if ((ifp = mib_find_if_sys(ifam.ifam_index)) == NULL) {
1068 syslog(LOG_WARNING, "RTM_NEWADDR for unknown "
1069 "interface %u", ifam.ifam_index);
1070 break;
1071 }
1072 if ((ifa = alloc_ifa(ifp->index, sa->sin_addr)) == NULL)
1073 break;
1074 }
1075 sa = (struct sockaddr_in *)(void *)addrs[RTAX_NETMASK];
1076 ifa->inmask = sa->sin_addr;
1077
1078 if (addrs[RTAX_BRD] != NULL) {
1079 sa = (struct sockaddr_in *)(void *)addrs[RTAX_BRD];
1080 ifa->inbcast = sa->sin_addr;
1081 }
1082 ifa->flags |= MIBIFA_FOUND;
1083 break;
1084
1085 case RTM_DELADDR:
1086 ifamp = (struct ifa_msghdr *)rtm;
1087 memcpy(&ifam, ifamp, sizeof(ifam));
1088 mib_extract_addrs(ifam.ifam_addrs, (u_char *)(ifamp + 1), addrs);
1089 if (addrs[RTAX_IFA] == NULL)
1090 break;
1091
1092 sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
1093 if ((ifa = mib_find_ifa(sa->sin_addr)) != NULL) {
1094 ifa->flags |= MIBIFA_FOUND;
1095 if (!(ifa->flags & MIBIFA_DESTROYED))
1096 destroy_ifa(ifa);
1097 }
1098 break;
1099
1100 case RTM_NEWMADDR:
1101 ifmam = (struct ifma_msghdr *)rtm;
1102 mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1103 if (addrs[RTAX_IFA] == NULL ||
1104 addrs[RTAX_IFA]->sa_family != AF_LINK)
1105 break;
1106 sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1107 if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1108 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) {
1109 /* unknown address */
1110 if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) {
1111 syslog(LOG_WARNING, "RTM_NEWMADDR for unknown "
1112 "interface %u", sdl->sdl_index);
1113 break;
1114 }
1115 if ((rcv = mib_rcvaddr_create(ifp,
1116 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
1117 break;
1118 rcv->flags |= MIBRCVADDR_VOLATILE;
1119 }
1120 rcv->flags |= MIBRCVADDR_FOUND;
1121 break;
1122
1123 case RTM_DELMADDR:
1124 ifmam = (struct ifma_msghdr *)rtm;
1125 mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
1126 if (addrs[RTAX_IFA] == NULL ||
1127 addrs[RTAX_IFA]->sa_family != AF_LINK)
1128 break;
1129 sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
1130 if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
1131 sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) != NULL)
1132 mib_rcvaddr_delete(rcv);
1133 break;
1134
1135 case RTM_IFINFO:
1136 ifm = (struct if_msghdr *)(void *)rtm;
1137 mib_extract_addrs(ifm->ifm_addrs, (u_char *)(ifm + 1), addrs);
1138 if ((ifp = mib_find_if_sys(ifm->ifm_index)) == NULL)
1139 break;
1140 if (addrs[RTAX_IFP] != NULL &&
1141 addrs[RTAX_IFP]->sa_family == AF_LINK) {
1142 sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFP];
1143 ptr = sdl->sdl_data + sdl->sdl_nlen;
1144 get_physaddr(ifp, sdl, ptr);
1145 }
1146 (void)mib_fetch_ifmib(ifp);
1147 break;
1148
1149 #ifdef RTM_IFANNOUNCE
1150 case RTM_IFANNOUNCE:
1151 ifan = (struct if_announcemsghdr *)rtm;
1152 ifp = mib_find_if_sys(ifan->ifan_index);
1153
1154 switch (ifan->ifan_what) {
1155
1156 case IFAN_ARRIVAL:
1157 if (ifp == NULL && (ifp = mibif_create(ifan->ifan_index,
1158 ifan->ifan_name)) != NULL) {
1159 (void)mib_fetch_ifmib(ifp);
1160 check_llbcast(ifp);
1161 notify_newif(ifp);
1162 }
1163 break;
1164
1165 case IFAN_DEPARTURE:
1166 if (ifp != NULL)
1167 mibif_free(ifp);
1168 break;
1169 }
1170 break;
1171 #endif
1172 case RTM_GET:
1173 case RTM_ADD:
1174 mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1175 if (rtm->rtm_flags & RTF_LLINFO) {
1176 if (addrs[RTAX_DST] == NULL ||
1177 addrs[RTAX_GATEWAY] == NULL ||
1178 addrs[RTAX_DST]->sa_family != AF_INET ||
1179 addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
1180 break;
1181 process_arp(rtm,
1182 (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
1183 (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
1184 } else {
1185 if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1186 mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1187 addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1188 }
1189 break;
1190
1191 case RTM_DELETE:
1192 mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
1193
1194 if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
1195 mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
1196 addrs[RTAX_DST], addrs[RTAX_NETMASK]);
1197 break;
1198 }
1199 }
1200
1201 /*
1202 * send a routing message
1203 */
1204 void
mib_send_rtmsg(struct rt_msghdr * rtm,struct sockaddr * gw,struct sockaddr * dst,struct sockaddr * mask)1205 mib_send_rtmsg(struct rt_msghdr *rtm, struct sockaddr *gw,
1206 struct sockaddr *dst, struct sockaddr *mask)
1207 {
1208 size_t len;
1209 struct rt_msghdr *msg;
1210 char *cp;
1211 ssize_t sent;
1212
1213 len = sizeof(*rtm) + SA_SIZE(gw) + SA_SIZE(dst) + SA_SIZE(mask);
1214 if ((msg = malloc(len)) == NULL) {
1215 syslog(LOG_ERR, "%s: %m", __func__);
1216 return;
1217 }
1218 cp = (char *)(msg + 1);
1219
1220 memset(msg, 0, sizeof(*msg));
1221 msg->rtm_flags = 0;
1222 msg->rtm_version = RTM_VERSION;
1223 msg->rtm_addrs = RTA_DST | RTA_GATEWAY;
1224
1225 memcpy(cp, dst, SA_SIZE(dst));
1226 cp += SA_SIZE(dst);
1227 memcpy(cp, gw, SA_SIZE(gw));
1228 cp += SA_SIZE(gw);
1229 if (mask != NULL) {
1230 memcpy(cp, mask, SA_SIZE(mask));
1231 cp += SA_SIZE(mask);
1232 msg->rtm_addrs |= RTA_NETMASK;
1233 }
1234 msg->rtm_msglen = cp - (char *)msg;
1235 msg->rtm_type = RTM_GET;
1236 if ((sent = write(route, msg, msg->rtm_msglen)) == -1) {
1237 syslog(LOG_ERR, "%s: write: %m", __func__);
1238 free(msg);
1239 return;
1240 }
1241 if (sent != msg->rtm_msglen) {
1242 syslog(LOG_ERR, "%s: short write", __func__);
1243 free(msg);
1244 return;
1245 }
1246 free(msg);
1247 }
1248
1249 /*
1250 * Fetch the routing table via sysctl
1251 */
1252 u_char *
mib_fetch_rtab(int af,int info,int arg,size_t * lenp)1253 mib_fetch_rtab(int af, int info, int arg, size_t *lenp)
1254 {
1255 int name[6];
1256 u_char *buf, *newbuf;
1257
1258 name[0] = CTL_NET;
1259 name[1] = PF_ROUTE;
1260 name[2] = 0;
1261 name[3] = af;
1262 name[4] = info;
1263 name[5] = arg;
1264
1265 *lenp = 0;
1266
1267 /* initial estimate */
1268 if (sysctl(name, nitems(name), NULL, lenp, NULL, 0) == -1) {
1269 syslog(LOG_ERR, "sysctl estimate (%d,%d,%d,%d,%d,%d): %m",
1270 name[0], name[1], name[2], name[3], name[4], name[5]);
1271 return (NULL);
1272 }
1273 if (*lenp == 0)
1274 return (NULL);
1275
1276 buf = NULL;
1277 for (;;) {
1278 if ((newbuf = realloc(buf, *lenp)) == NULL) {
1279 syslog(LOG_ERR, "sysctl buffer: %m");
1280 free(buf);
1281 return (NULL);
1282 }
1283 buf = newbuf;
1284
1285 if (sysctl(name, nitems(name), buf, lenp, NULL, 0) == 0)
1286 break;
1287
1288 if (errno != ENOMEM) {
1289 syslog(LOG_ERR, "sysctl get: %m");
1290 free(buf);
1291 return (NULL);
1292 }
1293 *lenp += *lenp / 8 + 1;
1294 }
1295
1296 return (buf);
1297 }
1298
1299 /*
1300 * Update the following info: interface, interface addresses, interface
1301 * receive addresses, arp-table.
1302 * This does not change the interface list itself.
1303 */
1304 static void
update_ifa_info(void)1305 update_ifa_info(void)
1306 {
1307 u_char *buf, *next;
1308 struct rt_msghdr *rtm;
1309 struct mibifa *ifa, *ifa1;
1310 struct mibrcvaddr *rcv, *rcv1;
1311 size_t needed;
1312 static const int infos[][3] = {
1313 { 0, NET_RT_IFLIST, 0 },
1314 #ifdef NET_RT_IFMALIST
1315 { AF_LINK, NET_RT_IFMALIST, 0 },
1316 #endif
1317 };
1318 u_int i;
1319
1320 TAILQ_FOREACH(ifa, &mibifa_list, link)
1321 ifa->flags &= ~MIBIFA_FOUND;
1322 TAILQ_FOREACH(rcv, &mibrcvaddr_list, link)
1323 rcv->flags &= ~MIBRCVADDR_FOUND;
1324
1325 for (i = 0; i < sizeof(infos) / sizeof(infos[0]); i++) {
1326 if ((buf = mib_fetch_rtab(infos[i][0], infos[i][1], infos[i][2],
1327 &needed)) == NULL)
1328 continue;
1329
1330 next = buf;
1331 while (next < buf + needed) {
1332 rtm = (struct rt_msghdr *)(void *)next;
1333 next += rtm->rtm_msglen;
1334 handle_rtmsg(rtm);
1335 }
1336 free(buf);
1337 }
1338
1339 /*
1340 * Purge the address list of unused entries. These may happen for
1341 * interface aliases that are on the same subnet. We don't receive
1342 * routing socket messages for them.
1343 */
1344 ifa = TAILQ_FIRST(&mibifa_list);
1345 while (ifa != NULL) {
1346 ifa1 = TAILQ_NEXT(ifa, link);
1347 if (!(ifa->flags & MIBIFA_FOUND))
1348 destroy_ifa(ifa);
1349 ifa = ifa1;
1350 }
1351
1352 rcv = TAILQ_FIRST(&mibrcvaddr_list);
1353 while (rcv != NULL) {
1354 rcv1 = TAILQ_NEXT(rcv, link);
1355 if (!(rcv->flags & (MIBRCVADDR_FOUND | MIBRCVADDR_BCAST |
1356 MIBRCVADDR_HW)))
1357 mib_rcvaddr_delete(rcv);
1358 rcv = rcv1;
1359 }
1360 }
1361
1362 /*
1363 * Update arp table
1364 */
1365 void
mib_arp_update(void)1366 mib_arp_update(void)
1367 {
1368 struct mibarp *at, *at1;
1369 size_t needed;
1370 u_char *buf, *next;
1371 struct rt_msghdr *rtm;
1372
1373 if (in_update_arp)
1374 return; /* Aaargh */
1375 in_update_arp = 1;
1376
1377 TAILQ_FOREACH(at, &mibarp_list, link)
1378 at->flags &= ~MIBARP_FOUND;
1379
1380 if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, 0, &needed)) == NULL) {
1381 in_update_arp = 0;
1382 return;
1383 }
1384
1385 next = buf;
1386 while (next < buf + needed) {
1387 rtm = (struct rt_msghdr *)(void *)next;
1388 next += rtm->rtm_msglen;
1389 handle_rtmsg(rtm);
1390 }
1391 free(buf);
1392
1393 at = TAILQ_FIRST(&mibarp_list);
1394 while (at != NULL) {
1395 at1 = TAILQ_NEXT(at, link);
1396 if (!(at->flags & MIBARP_FOUND))
1397 mib_arp_delete(at);
1398 at = at1;
1399 }
1400 mibarpticks = get_ticks();
1401 in_update_arp = 0;
1402 }
1403
1404
1405 /*
1406 * Input on the routing socket.
1407 */
1408 static void
route_input(int fd,void * udata __unused)1409 route_input(int fd, void *udata __unused)
1410 {
1411 u_char buf[1024 * 16];
1412 ssize_t n;
1413 struct rt_msghdr *rtm;
1414
1415 if ((n = read(fd, buf, sizeof(buf))) == -1)
1416 err(1, "read(rt_socket)");
1417
1418 if (n == 0)
1419 errx(1, "EOF on rt_socket");
1420
1421 rtm = (struct rt_msghdr *)(void *)buf;
1422 if ((size_t)n != rtm->rtm_msglen)
1423 errx(1, "n=%zu, rtm_msglen=%u", (size_t)n, rtm->rtm_msglen);
1424
1425 handle_rtmsg(rtm);
1426 }
1427
1428 /*
1429 * execute and SIOCAIFADDR
1430 */
1431 static int
siocaifaddr(char * ifname,struct in_addr addr,struct in_addr mask,struct in_addr bcast)1432 siocaifaddr(char *ifname, struct in_addr addr, struct in_addr mask,
1433 struct in_addr bcast)
1434 {
1435 struct ifaliasreq addreq;
1436 struct sockaddr_in *sa;
1437
1438 memset(&addreq, 0, sizeof(addreq));
1439 strlcpy(addreq.ifra_name, ifname, sizeof(addreq.ifra_name));
1440
1441 sa = (struct sockaddr_in *)(void *)&addreq.ifra_addr;
1442 sa->sin_family = AF_INET;
1443 sa->sin_len = sizeof(*sa);
1444 sa->sin_addr = addr;
1445
1446 sa = (struct sockaddr_in *)(void *)&addreq.ifra_mask;
1447 sa->sin_family = AF_INET;
1448 sa->sin_len = sizeof(*sa);
1449 sa->sin_addr = mask;
1450
1451 sa = (struct sockaddr_in *)(void *)&addreq.ifra_broadaddr;
1452 sa->sin_family = AF_INET;
1453 sa->sin_len = sizeof(*sa);
1454 sa->sin_addr = bcast;
1455
1456 return (ioctl(mib_netsock, SIOCAIFADDR, &addreq));
1457 }
1458
1459 /*
1460 * Exececute a SIOCDIFADDR
1461 */
1462 static int
siocdifaddr(const char * ifname,struct in_addr addr)1463 siocdifaddr(const char *ifname, struct in_addr addr)
1464 {
1465 struct ifreq delreq;
1466 struct sockaddr_in *sa;
1467
1468 memset(&delreq, 0, sizeof(delreq));
1469 strlcpy(delreq.ifr_name, ifname, sizeof(delreq.ifr_name));
1470 sa = (struct sockaddr_in *)(void *)&delreq.ifr_addr;
1471 sa->sin_family = AF_INET;
1472 sa->sin_len = sizeof(*sa);
1473 sa->sin_addr = addr;
1474
1475 return (ioctl(mib_netsock, SIOCDIFADDR, &delreq));
1476 }
1477
1478 /*
1479 * Verify an interface address without fetching the entire list
1480 */
1481 static int
verify_ifa(const char * name,struct mibifa * ifa)1482 verify_ifa(const char *name, struct mibifa *ifa)
1483 {
1484 struct ifreq req;
1485 struct sockaddr_in *sa;
1486
1487 memset(&req, 0, sizeof(req));
1488 strlcpy(req.ifr_name, name, sizeof(req.ifr_name));
1489 sa = (struct sockaddr_in *)(void *)&req.ifr_addr;
1490 sa->sin_family = AF_INET;
1491 sa->sin_len = sizeof(*sa);
1492 sa->sin_addr = ifa->inaddr;
1493
1494 if (ioctl(mib_netsock, SIOCGIFADDR, &req) == -1)
1495 return (-1);
1496 if (ifa->inaddr.s_addr != sa->sin_addr.s_addr) {
1497 syslog(LOG_ERR, "%s: address mismatch", __func__);
1498 return (-1);
1499 }
1500
1501 if (ioctl(mib_netsock, SIOCGIFNETMASK, &req) == -1)
1502 return (-1);
1503 if (ifa->inmask.s_addr != sa->sin_addr.s_addr) {
1504 syslog(LOG_ERR, "%s: netmask mismatch", __func__);
1505 return (-1);
1506 }
1507 return (0);
1508 }
1509
1510 /*
1511 * Restore a deleted interface address. Don't wait for the routing socket
1512 * to update us.
1513 */
1514 void
mib_undestroy_ifa(struct mibifa * ifa)1515 mib_undestroy_ifa(struct mibifa *ifa)
1516 {
1517 struct mibif *ifp;
1518
1519 if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
1520 /* keep it destroyed */
1521 return;
1522
1523 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast))
1524 /* keep it destroyed */
1525 return;
1526
1527 ifa->flags &= ~MIBIFA_DESTROYED;
1528 }
1529
1530 /*
1531 * Destroy an interface address
1532 */
1533 int
mib_destroy_ifa(struct mibifa * ifa)1534 mib_destroy_ifa(struct mibifa *ifa)
1535 {
1536 struct mibif *ifp;
1537
1538 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1539 /* ups. */
1540 mib_iflist_bad = 1;
1541 return (-1);
1542 }
1543 if (siocdifaddr(ifp->name, ifa->inaddr)) {
1544 /* ups. */
1545 syslog(LOG_ERR, "SIOCDIFADDR: %m");
1546 mib_iflist_bad = 1;
1547 return (-1);
1548 }
1549 ifa->flags |= MIBIFA_DESTROYED;
1550 return (0);
1551 }
1552
1553 /*
1554 * Rollback the modification of an address. Don't bother to wait for
1555 * the routing socket.
1556 */
1557 void
mib_unmodify_ifa(struct mibifa * ifa)1558 mib_unmodify_ifa(struct mibifa *ifa)
1559 {
1560 struct mibif *ifp;
1561
1562 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1563 /* ups. */
1564 mib_iflist_bad = 1;
1565 return;
1566 }
1567
1568 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1569 /* ups. */
1570 mib_iflist_bad = 1;
1571 return;
1572 }
1573 }
1574
1575 /*
1576 * Modify an IFA.
1577 */
1578 int
mib_modify_ifa(struct mibifa * ifa)1579 mib_modify_ifa(struct mibifa *ifa)
1580 {
1581 struct mibif *ifp;
1582
1583 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1584 /* ups. */
1585 mib_iflist_bad = 1;
1586 return (-1);
1587 }
1588
1589 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1590 /* ups. */
1591 mib_iflist_bad = 1;
1592 return (-1);
1593 }
1594
1595 if (verify_ifa(ifp->name, ifa)) {
1596 /* ups. */
1597 mib_iflist_bad = 1;
1598 return (-1);
1599 }
1600
1601 return (0);
1602 }
1603
1604 /*
1605 * Destroy a freshly created interface address. Don't bother to wait for
1606 * the routing socket.
1607 */
1608 void
mib_uncreate_ifa(struct mibifa * ifa)1609 mib_uncreate_ifa(struct mibifa *ifa)
1610 {
1611 struct mibif *ifp;
1612
1613 if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
1614 /* ups. */
1615 mib_iflist_bad = 1;
1616 return;
1617 }
1618 if (siocdifaddr(ifp->name, ifa->inaddr)) {
1619 /* ups. */
1620 mib_iflist_bad = 1;
1621 return;
1622 }
1623
1624 destroy_ifa(ifa);
1625 }
1626
1627 /*
1628 * Create a new ifa and verify it
1629 */
1630 struct mibifa *
mib_create_ifa(u_int ifindex,struct in_addr addr,struct in_addr mask,struct in_addr bcast)1631 mib_create_ifa(u_int ifindex, struct in_addr addr, struct in_addr mask,
1632 struct in_addr bcast)
1633 {
1634 struct mibif *ifp;
1635 struct mibifa *ifa;
1636
1637 if ((ifp = mib_find_if(ifindex)) == NULL)
1638 return (NULL);
1639 if ((ifa = alloc_ifa(ifindex, addr)) == NULL)
1640 return (NULL);
1641 ifa->inmask = mask;
1642 ifa->inbcast = bcast;
1643
1644 if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
1645 syslog(LOG_ERR, "%s: %m", __func__);
1646 destroy_ifa(ifa);
1647 return (NULL);
1648 }
1649 if (verify_ifa(ifp->name, ifa)) {
1650 destroy_ifa(ifa);
1651 return (NULL);
1652 }
1653 return (ifa);
1654 }
1655
1656 /*
1657 * Get all cloning interfaces and make them dynamic.
1658 * Hah! Whe should probably do this on a periodic basis (XXX).
1659 */
1660 static void
get_cloners(void)1661 get_cloners(void)
1662 {
1663 struct if_clonereq req;
1664 char *buf, *cp;
1665 int i;
1666
1667 memset(&req, 0, sizeof(req));
1668 if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1669 syslog(LOG_ERR, "get cloners: %m");
1670 return;
1671 }
1672 if ((buf = malloc(req.ifcr_total * IFNAMSIZ)) == NULL) {
1673 syslog(LOG_ERR, "%m");
1674 return;
1675 }
1676 req.ifcr_count = req.ifcr_total;
1677 req.ifcr_buffer = buf;
1678 if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
1679 syslog(LOG_ERR, "get cloners: %m");
1680 free(buf);
1681 return;
1682 }
1683 for (cp = buf, i = 0; i < req.ifcr_total; i++, cp += IFNAMSIZ)
1684 mib_if_set_dyn(cp);
1685 free(buf);
1686 }
1687
1688 /*
1689 * Idle function
1690 */
1691 static void
mibII_idle(void * arg __unused)1692 mibII_idle(void *arg __unused)
1693 {
1694 struct mibifa *ifa;
1695
1696 if (mib_iflist_bad) {
1697 TAILQ_FOREACH(ifa, &mibifa_list, link)
1698 ifa->flags &= ~MIBIFA_DESTROYED;
1699
1700 /* assume, that all cloning interfaces are dynamic */
1701 get_cloners();
1702
1703 mib_refresh_iflist();
1704 update_ifa_info();
1705 mib_arp_update();
1706 mib_iflist_bad = 0;
1707 }
1708
1709 mib_arp_update();
1710 }
1711
1712
1713 /*
1714 * Start the module
1715 */
1716 static void
mibII_start(void)1717 mibII_start(void)
1718 {
1719 if ((route_fd = fd_select(route, route_input, NULL, module)) == NULL) {
1720 syslog(LOG_ERR, "fd_select(route): %m");
1721 return;
1722 }
1723 mib_refresh_iflist();
1724 update_ifa_info();
1725 mib_arp_update();
1726 (void)mib_fetch_route();
1727 mib_iftable_last_change = 0;
1728 mib_ifstack_last_change = 0;
1729
1730 ifmib_reg = or_register(&oid_ifMIB,
1731 "The MIB module to describe generic objects for network interface"
1732 " sub-layers.", module);
1733
1734 ipmib_reg = or_register(&oid_ipMIB,
1735 "The MIB module for managing IP and ICMP implementations, but "
1736 "excluding their management of IP routes.", module);
1737
1738 tcpmib_reg = or_register(&oid_tcpMIB,
1739 "The MIB module for managing TCP implementations.", module);
1740
1741 udpmib_reg = or_register(&oid_udpMIB,
1742 "The MIB module for managing UDP implementations.", module);
1743
1744 ipForward_reg = or_register(&oid_ipForward,
1745 "The MIB module for the display of CIDR multipath IP Routes.",
1746 module);
1747
1748 mibII_poll_timer = NULL;
1749 mibII_poll_ticks = MIBII_POLL_TICKS;
1750 mibif_restart_mibII_poll_timer();
1751 }
1752
1753 /*
1754 * Initialize the module
1755 */
1756 static int
mibII_init(struct lmodule * mod,int argc __unused,char * argv[]__unused)1757 mibII_init(struct lmodule *mod, int argc __unused, char *argv[] __unused)
1758 {
1759 size_t len;
1760
1761 module = mod;
1762
1763 len = sizeof(clockinfo);
1764 if (sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0) == -1) {
1765 syslog(LOG_ERR, "kern.clockrate: %m");
1766 return (-1);
1767 }
1768 if (len != sizeof(clockinfo)) {
1769 syslog(LOG_ERR, "kern.clockrate: wrong size");
1770 return (-1);
1771 }
1772
1773 if ((route = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) == -1) {
1774 syslog(LOG_ERR, "PF_ROUTE: %m");
1775 return (-1);
1776 }
1777
1778 if ((mib_netsock = socket(PF_INET, SOCK_DGRAM, 0)) == -1) {
1779 syslog(LOG_ERR, "PF_INET: %m");
1780 (void)close(route);
1781 return (-1);
1782 }
1783 (void)shutdown(mib_netsock, SHUT_RDWR);
1784
1785 /* assume, that all cloning interfaces are dynamic */
1786 get_cloners();
1787
1788 return (0);
1789 }
1790
1791 static int
mibII_fini(void)1792 mibII_fini(void)
1793 {
1794 if (mibII_poll_timer != NULL ) {
1795 timer_stop(mibII_poll_timer);
1796 mibII_poll_timer = NULL;
1797 }
1798
1799 if (route_fd != NULL)
1800 fd_deselect(route_fd);
1801 if (route != -1)
1802 (void)close(route);
1803 if (mib_netsock != -1)
1804 (void)close(mib_netsock);
1805 /* XXX free memory */
1806
1807 or_unregister(ipForward_reg);
1808 or_unregister(udpmib_reg);
1809 or_unregister(tcpmib_reg);
1810 or_unregister(ipmib_reg);
1811 or_unregister(ifmib_reg);
1812
1813 return (0);
1814 }
1815
1816 static void
mibII_loading(const struct lmodule * mod,int loaded)1817 mibII_loading(const struct lmodule *mod, int loaded)
1818 {
1819 struct mibif *ifp;
1820
1821 if (loaded == 1)
1822 return;
1823
1824 TAILQ_FOREACH(ifp, &mibif_list, link)
1825 if (ifp->xnotify_mod == mod) {
1826 ifp->xnotify_mod = NULL;
1827 ifp->xnotify_data = NULL;
1828 ifp->xnotify = NULL;
1829 }
1830
1831 mib_unregister_newif(mod);
1832 }
1833
1834 extern const struct snmp_module config;
1835 const struct snmp_module config = {
1836 "This module implements the interface and ip groups.",
1837 mibII_init,
1838 mibII_fini,
1839 NULL, /* idle */
1840 NULL, /* dump */
1841 NULL, /* config */
1842 mibII_start,
1843 NULL,
1844 mibII_ctree,
1845 mibII_CTREE_SIZE,
1846 mibII_loading
1847 };
1848
1849 /*
1850 * Should have a list of these attached to each interface.
1851 */
1852 void *
mibif_notify(struct mibif * ifp,const struct lmodule * mod,mibif_notify_f func,void * data)1853 mibif_notify(struct mibif *ifp, const struct lmodule *mod,
1854 mibif_notify_f func, void *data)
1855 {
1856 ifp->xnotify = func;
1857 ifp->xnotify_data = data;
1858 ifp->xnotify_mod = mod;
1859
1860 return (ifp);
1861 }
1862
1863 void
mibif_unnotify(void * arg)1864 mibif_unnotify(void *arg)
1865 {
1866 struct mibif *ifp = arg;
1867
1868 ifp->xnotify = NULL;
1869 ifp->xnotify_data = NULL;
1870 ifp->xnotify_mod = NULL;
1871 }
1872