1 /*-
2 * Copyright (c) 2007 Bruce M. Simpson.
3 * Copyright (c) 2005 Robert N. M. Watson.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote
15 * products derived from this software without specific prior written
16 * permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 /*
32 * IPv4 multicast socket, group, and socket option processing module.
33 * Until further notice, this file requires INET to compile.
34 * TODO: Make this infrastructure independent of address family.
35 * TODO: Teach netinet6 to use this code.
36 * TODO: Hook up SSM logic to IGMPv3/MLDv2.
37 */
38
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/kernel.h>
45 #include <sys/malloc.h>
46 #include <sys/mbuf.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/sysctl.h>
51
52 #include <net/if.h>
53 #include <net/if_dl.h>
54 #include <net/route.h>
55
56 #include <netinet/in.h>
57 #include <netinet/in_systm.h>
58 #include <netinet/in_pcb.h>
59 #include <netinet/in_var.h>
60 #include <netinet/ip_var.h>
61 #include <netinet/igmp_var.h>
62
63 #ifndef __SOCKUNION_DECLARED
64 union sockunion {
65 struct sockaddr_storage ss;
66 struct sockaddr sa;
67 struct sockaddr_dl sdl;
68 struct sockaddr_in sin;
69 #ifdef INET6
70 struct sockaddr_in6 sin6;
71 #endif
72 };
73 typedef union sockunion sockunion_t;
74 #define __SOCKUNION_DECLARED
75 #endif /* __SOCKUNION_DECLARED */
76
77 static MALLOC_DEFINE(M_IPMADDR, "in_multi", "IPv4 multicast group");
78 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "IPv4 multicast options");
79 static MALLOC_DEFINE(M_IPMSOURCE, "in_msource", "IPv4 multicast source filter");
80
81 /*
82 * The IPv4 multicast list (in_multihead and associated structures) are
83 * protected by the global in_multi_mtx. See in_var.h for more details. For
84 * now, in_multi_mtx is marked as recursible due to IGMP's calling back into
85 * ip_output() to send IGMP packets while holding the lock; this probably is
86 * not quite desirable.
87 */
88 struct in_multihead in_multihead; /* XXX BSS initialization */
89 struct mtx in_multi_mtx;
90 MTX_SYSINIT(in_multi_mtx, &in_multi_mtx, "in_multi_mtx", MTX_DEF | MTX_RECURSE);
91
92 /*
93 * Functions with non-static linkage defined in this file should be
94 * declared in in_var.h:
95 * imo_match_group()
96 * imo_match_source()
97 * in_addmulti()
98 * in_delmulti()
99 * in_delmulti_locked()
100 * and ip_var.h:
101 * inp_freemoptions()
102 * inp_getmoptions()
103 * inp_setmoptions()
104 */
105 static int imo_grow(struct ip_moptions *);
106 static int imo_join_source(struct ip_moptions *, size_t, sockunion_t *);
107 static int imo_leave_source(struct ip_moptions *, size_t, sockunion_t *);
108 static int inp_change_source_filter(struct inpcb *, struct sockopt *);
109 static struct ip_moptions *
110 inp_findmoptions(struct inpcb *);
111 static int inp_get_source_filters(struct inpcb *, struct sockopt *);
112 static int inp_join_group(struct inpcb *, struct sockopt *);
113 static int inp_leave_group(struct inpcb *, struct sockopt *);
114 static int inp_set_multicast_if(struct inpcb *, struct sockopt *);
115 static int inp_set_source_filters(struct inpcb *, struct sockopt *);
116 static struct ifnet *
117 ip_multicast_if(struct in_addr *a);
118
119 /*
120 * Resize the ip_moptions vector to the next power-of-two minus 1.
121 * May be called with locks held; do not sleep.
122 */
123 static int
124 imo_grow(struct ip_moptions *imo)
125 {
126 struct in_multi **nmships;
127 struct in_multi **omships;
128 struct in_mfilter *nmfilters;
129 struct in_mfilter *omfilters;
130 size_t idx;
131 size_t newmax;
132 size_t oldmax;
133
134 nmships = NULL;
135 nmfilters = NULL;
136 omships = imo->imo_membership;
137 omfilters = imo->imo_mfilters;
138 oldmax = imo->imo_max_memberships;
139 newmax = ((oldmax + 1) * 2) - 1;
140
141 if (newmax <= IP_MAX_MEMBERSHIPS) {
142 nmships = (struct in_multi **)realloc(omships,
143 sizeof(struct in_multi *) * newmax, M_IPMOPTS, M_NOWAIT);
144 nmfilters = (struct in_mfilter *)realloc(omfilters,
145 sizeof(struct in_mfilter) * newmax, M_IPMSOURCE, M_NOWAIT);
146 if (nmships != NULL && nmfilters != NULL) {
147 /* Initialize newly allocated source filter heads. */
148 for (idx = oldmax; idx < newmax; idx++) {
149 nmfilters[idx].imf_fmode = MCAST_EXCLUDE;
150 nmfilters[idx].imf_nsources = 0;
151 TAILQ_INIT(&nmfilters[idx].imf_sources);
152 }
153 imo->imo_max_memberships = newmax;
154 imo->imo_membership = nmships;
155 imo->imo_mfilters = nmfilters;
156 }
157 }
158
159 if (nmships == NULL || nmfilters == NULL) {
160 if (nmships != NULL)
161 free(nmships, M_IPMOPTS);
162 if (nmfilters != NULL)
163 free(nmfilters, M_IPMSOURCE);
164 return (ETOOMANYREFS);
165 }
166
167 return (0);
168 }
169
170 /*
171 * Add a source to a multicast filter list.
172 * Assumes the associated inpcb is locked.
173 */
174 static int
175 imo_join_source(struct ip_moptions *imo, size_t gidx, sockunion_t *src)
176 {
177 struct in_msource *ims, *nims;
178 struct in_mfilter *imf;
179
180 KASSERT(src->ss.ss_family == AF_INET, ("%s: !AF_INET", __func__));
181 KASSERT(imo->imo_mfilters != NULL,
182 ("%s: imo_mfilters vector not allocated", __func__));
183
184 imf = &imo->imo_mfilters[gidx];
185 if (imf->imf_nsources == IP_MAX_SOURCE_FILTER)
186 return (ENOBUFS);
187
188 ims = imo_match_source(imo, gidx, &src->sa);
189 if (ims != NULL)
190 return (EADDRNOTAVAIL);
191
192 /* Do not sleep with inp lock held. */
193 MALLOC(nims, struct in_msource *, sizeof(struct in_msource),
194 M_IPMSOURCE, M_NOWAIT | M_ZERO);
195 if (nims == NULL)
196 return (ENOBUFS);
197
198 nims->ims_addr = src->ss;
199 TAILQ_INSERT_TAIL(&imf->imf_sources, nims, ims_next);
200 imf->imf_nsources++;
201
202 return (0);
203 }
204
205 static int
206 imo_leave_source(struct ip_moptions *imo, size_t gidx, sockunion_t *src)
207 {
208 struct in_msource *ims;
209 struct in_mfilter *imf;
210
211 KASSERT(src->ss.ss_family == AF_INET, ("%s: !AF_INET", __func__));
212 KASSERT(imo->imo_mfilters != NULL,
213 ("%s: imo_mfilters vector not allocated", __func__));
214
215 imf = &imo->imo_mfilters[gidx];
216 if (imf->imf_nsources == IP_MAX_SOURCE_FILTER)
217 return (ENOBUFS);
218
219 ims = imo_match_source(imo, gidx, &src->sa);
220 if (ims == NULL)
221 return (EADDRNOTAVAIL);
222
223 TAILQ_REMOVE(&imf->imf_sources, ims, ims_next);
224 FREE(ims, M_IPMSOURCE);
225 imf->imf_nsources--;
226
227 return (0);
228 }
229
230 /*
231 * Find an IPv4 multicast group entry for this ip_moptions instance
232 * which matches the specified group, and optionally an interface.
233 * Return its index into the array, or -1 if not found.
234 */
235 size_t
236 imo_match_group(struct ip_moptions *imo, struct ifnet *ifp,
237 struct sockaddr *group)
238 {
239 sockunion_t *gsa;
240 struct in_multi **pinm;
241 int idx;
242 int nmships;
243
244 gsa = (sockunion_t *)group;
245
246 /* The imo_membership array may be lazy allocated. */
247 if (imo->imo_membership == NULL || imo->imo_num_memberships == 0)
248 return (-1);
249
250 nmships = imo->imo_num_memberships;
251 pinm = &imo->imo_membership[0];
252 for (idx = 0; idx < nmships; idx++, pinm++) {
253 if (*pinm == NULL)
254 continue;
255 #if 0
256 printf("%s: trying ifp = %p, inaddr = %s ", __func__,
257 ifp, inet_ntoa(gsa->sin.sin_addr));
258 printf("against %p, %s\n",
259 (*pinm)->inm_ifp, inet_ntoa((*pinm)->inm_addr));
260 #endif
261 if ((ifp == NULL || ((*pinm)->inm_ifp == ifp)) &&
262 (*pinm)->inm_addr.s_addr == gsa->sin.sin_addr.s_addr) {
263 break;
264 }
265 }
266 if (idx >= nmships)
267 idx = -1;
268
269 return (idx);
270 }
271
272 /*
273 * Find a multicast source entry for this imo which matches
274 * the given group index for this socket, and source address.
275 */
276 struct in_msource *
277 imo_match_source(struct ip_moptions *imo, size_t gidx, struct sockaddr *src)
278 {
279 struct in_mfilter *imf;
280 struct in_msource *ims, *pims;
281
282 KASSERT(src->sa_family == AF_INET, ("%s: !AF_INET", __func__));
283 KASSERT(gidx != -1 && gidx < imo->imo_num_memberships,
284 ("%s: invalid index %d\n", __func__, (int)gidx));
285
286 /* The imo_mfilters array may be lazy allocated. */
287 if (imo->imo_mfilters == NULL)
288 return (NULL);
289
290 pims = NULL;
291 imf = &imo->imo_mfilters[gidx];
292 TAILQ_FOREACH(ims, &imf->imf_sources, ims_next) {
293 /*
294 * Perform bitwise comparison of two IPv4 addresses.
295 * TODO: Do the same for IPv6.
296 * Do not use sa_equal() for this as it is not aware of
297 * deeper structure in sockaddr_in or sockaddr_in6.
298 */
299 if (((struct sockaddr_in *)&ims->ims_addr)->sin_addr.s_addr ==
300 ((struct sockaddr_in *)src)->sin_addr.s_addr) {
301 pims = ims;
302 break;
303 }
304 }
305
306 return (pims);
307 }
308
309 /*
310 * Join an IPv4 multicast group.
311 */
312 struct in_multi *
313 in_addmulti(struct in_addr *ap, struct ifnet *ifp)
314 {
315 struct in_multi *inm;
316
317 inm = NULL;
318
319 IFF_LOCKGIANT(ifp);
320 IN_MULTI_LOCK();
321
322 IN_LOOKUP_MULTI(*ap, ifp, inm);
323 if (inm != NULL) {
324 /*
325 * If we already joined this group, just bump the
326 * refcount and return it.
327 */
328 KASSERT(inm->inm_refcount >= 1,
329 ("%s: bad refcount %d", __func__, inm->inm_refcount));
330 ++inm->inm_refcount;
331 } else do {
332 sockunion_t gsa;
333 struct ifmultiaddr *ifma;
334 struct in_multi *ninm;
335 int error;
336
337 memset(&gsa, 0, sizeof(gsa));
338 gsa.sin.sin_family = AF_INET;
339 gsa.sin.sin_len = sizeof(struct sockaddr_in);
340 gsa.sin.sin_addr = *ap;
341
342 /*
343 * Check if a link-layer group is already associated
344 * with this network-layer group on the given ifnet.
345 * If so, bump the refcount on the existing network-layer
346 * group association and return it.
347 */
348 error = if_addmulti(ifp, &gsa.sa, &ifma);
349 if (error)
350 break;
351 if (ifma->ifma_protospec != NULL) {
352 inm = (struct in_multi *)ifma->ifma_protospec;
353 #ifdef INVARIANTS
354 if (inm->inm_ifma != ifma || inm->inm_ifp != ifp ||
355 inm->inm_addr.s_addr != ap->s_addr)
356 panic("%s: ifma is inconsistent", __func__);
357 #endif
358 ++inm->inm_refcount;
359 break;
360 }
361
362 /*
363 * A new membership is needed; construct it and
364 * perform the IGMP join.
365 */
366 ninm = malloc(sizeof(*ninm), M_IPMADDR, M_NOWAIT | M_ZERO);
367 if (ninm == NULL) {
368 if_delmulti_ifma(ifma);
369 break;
370 }
371 ninm->inm_addr = *ap;
372 ninm->inm_ifp = ifp;
373 ninm->inm_ifma = ifma;
374 ninm->inm_refcount = 1;
375 ifma->ifma_protospec = ninm;
376 LIST_INSERT_HEAD(&in_multihead, ninm, inm_link);
377
378 igmp_joingroup(ninm);
379
380 inm = ninm;
381 } while (0);
382
383 IN_MULTI_UNLOCK();
384 IFF_UNLOCKGIANT(ifp);
385
386 return (inm);
387 }
388
389 /*
390 * Leave an IPv4 multicast group.
391 * It is OK to call this routine if the underlying ifnet went away.
392 *
393 * XXX: To deal with the ifp going away, we cheat; the link-layer code in net
394 * will set ifma_ifp to NULL when the associated ifnet instance is detached
395 * from the system.
396 *
397 * The only reason we need to violate layers and check ifma_ifp here at all
398 * is because certain hardware drivers still require Giant to be held,
399 * and it must always be taken before other locks.
400 */
401 void
402 in_delmulti(struct in_multi *inm)
403 {
404 struct ifnet *ifp;
405
406 KASSERT(inm != NULL, ("%s: inm is NULL", __func__));
407 KASSERT(inm->inm_ifma != NULL, ("%s: no ifma", __func__));
408 ifp = inm->inm_ifma->ifma_ifp;
409
410 if (ifp != NULL) {
411 /*
412 * Sanity check that netinet's notion of ifp is the
413 * same as net's.
414 */
415 KASSERT(inm->inm_ifp == ifp, ("%s: bad ifp", __func__));
416 IFF_LOCKGIANT(ifp);
417 }
418
419 IN_MULTI_LOCK();
420 in_delmulti_locked(inm);
421 IN_MULTI_UNLOCK();
422
423 if (ifp != NULL)
424 IFF_UNLOCKGIANT(ifp);
425 }
426
427 /*
428 * Delete a multicast address record, with locks held.
429 *
430 * It is OK to call this routine if the ifp went away.
431 * Assumes that caller holds the IN_MULTI lock, and that
432 * Giant was taken before other locks if required by the hardware.
433 */
434 void
435 in_delmulti_locked(struct in_multi *inm)
436 {
437 struct ifmultiaddr *ifma;
438
439 IN_MULTI_LOCK_ASSERT();
440 KASSERT(inm->inm_refcount >= 1, ("%s: freeing freed inm", __func__));
441
442 if (--inm->inm_refcount == 0) {
443 igmp_leavegroup(inm);
444
445 ifma = inm->inm_ifma;
446 #ifdef DIAGNOSTIC
447 if (bootverbose)
448 printf("%s: purging ifma %p\n", __func__, ifma);
449 #endif
450 KASSERT(ifma->ifma_protospec == inm,
451 ("%s: ifma_protospec != inm", __func__));
452 ifma->ifma_protospec = NULL;
453
454 LIST_REMOVE(inm, inm_link);
455 free(inm, M_IPMADDR);
456
457 if_delmulti_ifma(ifma);
458 }
459 }
460
461 /*
462 * Block or unblock an ASM/SSM multicast source on an inpcb.
463 */
464 static int
465 inp_change_source_filter(struct inpcb *inp, struct sockopt *sopt)
466 {
467 struct group_source_req gsr;
468 sockunion_t *gsa, *ssa;
469 struct ifnet *ifp;
470 struct in_mfilter *imf;
471 struct ip_moptions *imo;
472 struct in_msource *ims;
473 size_t idx;
474 int error;
475 int block;
476
477 ifp = NULL;
478 error = 0;
479 block = 0;
480
481 memset(&gsr, 0, sizeof(struct group_source_req));
482 gsa = (sockunion_t *)&gsr.gsr_group;
483 ssa = (sockunion_t *)&gsr.gsr_source;
484
485 switch (sopt->sopt_name) {
486 case IP_BLOCK_SOURCE:
487 case IP_UNBLOCK_SOURCE: {
488 struct ip_mreq_source mreqs;
489
490 error = sooptcopyin(sopt, &mreqs,
491 sizeof(struct ip_mreq_source),
492 sizeof(struct ip_mreq_source));
493 if (error)
494 return (error);
495
496 gsa->sin.sin_family = AF_INET;
497 gsa->sin.sin_len = sizeof(struct sockaddr_in);
498 gsa->sin.sin_addr = mreqs.imr_multiaddr;
499
500 ssa->sin.sin_family = AF_INET;
501 ssa->sin.sin_len = sizeof(struct sockaddr_in);
502 ssa->sin.sin_addr = mreqs.imr_sourceaddr;
503
504 if (mreqs.imr_interface.s_addr != INADDR_ANY)
505 INADDR_TO_IFP(mreqs.imr_interface, ifp);
506
507 if (sopt->sopt_name == IP_BLOCK_SOURCE)
508 block = 1;
509
510 #ifdef DIAGNOSTIC
511 if (bootverbose) {
512 printf("%s: imr_interface = %s, ifp = %p\n",
513 __func__, inet_ntoa(mreqs.imr_interface), ifp);
514 }
515 #endif
516 break;
517 }
518
519 case MCAST_BLOCK_SOURCE:
520 case MCAST_UNBLOCK_SOURCE:
521 error = sooptcopyin(sopt, &gsr,
522 sizeof(struct group_source_req),
523 sizeof(struct group_source_req));
524 if (error)
525 return (error);
526
527 if (gsa->sin.sin_family != AF_INET ||
528 gsa->sin.sin_len != sizeof(struct sockaddr_in))
529 return (EINVAL);
530
531 if (ssa->sin.sin_family != AF_INET ||
532 ssa->sin.sin_len != sizeof(struct sockaddr_in))
533 return (EINVAL);
534
535 if (gsr.gsr_interface == 0 || if_index < gsr.gsr_interface)
536 return (EADDRNOTAVAIL);
537
538 ifp = ifnet_byindex(gsr.gsr_interface);
539
540 if (sopt->sopt_name == MCAST_BLOCK_SOURCE)
541 block = 1;
542 break;
543
544 default:
545 #ifdef DIAGNOSTIC
546 if (bootverbose) {
547 printf("%s: unknown sopt_name %d\n", __func__,
548 sopt->sopt_name);
549 }
550 #endif
551 return (EOPNOTSUPP);
552 break;
553 }
554
555 /* XXX INET6 */
556 if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
557 return (EINVAL);
558
559 /*
560 * Check if we are actually a member of this group.
561 */
562 imo = inp_findmoptions(inp);
563 idx = imo_match_group(imo, ifp, &gsa->sa);
564 if (idx == -1 || imo->imo_mfilters == NULL) {
565 error = EADDRNOTAVAIL;
566 goto out_locked;
567 }
568
569 KASSERT(imo->imo_mfilters != NULL,
570 ("%s: imo_mfilters not allocated", __func__));
571 imf = &imo->imo_mfilters[idx];
572
573 /*
574 * SSM multicast truth table for block/unblock operations.
575 *
576 * Operation Filter Mode Entry exists? Action
577 *
578 * block exclude no add source to filter
579 * unblock include no add source to filter
580 * block include no EINVAL
581 * unblock exclude no EINVAL
582 * block exclude yes EADDRNOTAVAIL
583 * unblock include yes EADDRNOTAVAIL
584 * block include yes remove source from filter
585 * unblock exclude yes remove source from filter
586 *
587 * FreeBSD does not explicitly distinguish between ASM and SSM
588 * mode sockets; all sockets are assumed to have a filter list.
589 */
590 #ifdef DIAGNOSTIC
591 if (bootverbose) {
592 printf("%s: imf_fmode is %s\n", __func__,
593 imf->imf_fmode == MCAST_INCLUDE ? "include" : "exclude");
594 }
595 #endif
596 ims = imo_match_source(imo, idx, &ssa->sa);
597 if (ims == NULL) {
598 if ((block == 1 && imf->imf_fmode == MCAST_EXCLUDE) ||
599 (block == 0 && imf->imf_fmode == MCAST_INCLUDE)) {
600 #ifdef DIAGNOSTIC
601 if (bootverbose) {
602 printf("%s: adding %s to filter list\n",
603 __func__, inet_ntoa(ssa->sin.sin_addr));
604 }
605 #endif
606 error = imo_join_source(imo, idx, ssa);
607 }
608 if ((block == 1 && imf->imf_fmode == MCAST_INCLUDE) ||
609 (block == 0 && imf->imf_fmode == MCAST_EXCLUDE)) {
610 /*
611 * If the socket is in inclusive mode:
612 * the source is already blocked as it has no entry.
613 * If the socket is in exclusive mode:
614 * the source is already unblocked as it has no entry.
615 */
616 #ifdef DIAGNOSTIC
617 if (bootverbose) {
618 printf("%s: ims %p; %s already [un]blocked\n",
619 __func__, ims,
620 inet_ntoa(ssa->sin.sin_addr));
621 }
622 #endif
623 error = EINVAL;
624 }
625 } else {
626 if ((block == 1 && imf->imf_fmode == MCAST_EXCLUDE) ||
627 (block == 0 && imf->imf_fmode == MCAST_INCLUDE)) {
628 /*
629 * If the socket is in exclusive mode:
630 * the source is already blocked as it has an entry.
631 * If the socket is in inclusive mode:
632 * the source is already unblocked as it has an entry.
633 */
634 #ifdef DIAGNOSTIC
635 if (bootverbose) {
636 printf("%s: ims %p; %s already [un]blocked\n",
637 __func__, ims,
638 inet_ntoa(ssa->sin.sin_addr));
639 }
640 #endif
641 error = EADDRNOTAVAIL;
642 }
643 if ((block == 1 && imf->imf_fmode == MCAST_INCLUDE) ||
644 (block == 0 && imf->imf_fmode == MCAST_EXCLUDE)) {
645 #ifdef DIAGNOSTIC
646 if (bootverbose) {
647 printf("%s: removing %s from filter list\n",
648 __func__, inet_ntoa(ssa->sin.sin_addr));
649 }
650 #endif
651 error = imo_leave_source(imo, idx, ssa);
652 }
653 }
654
655 out_locked:
656 INP_UNLOCK(inp);
657 return (error);
658 }
659
660 /*
661 * Given an inpcb, return its multicast options structure pointer. Accepts
662 * an unlocked inpcb pointer, but will return it locked. May sleep.
663 */
664 static struct ip_moptions *
665 inp_findmoptions(struct inpcb *inp)
666 {
667 struct ip_moptions *imo;
668 struct in_multi **immp;
669 struct in_mfilter *imfp;
670 size_t idx;
671
672 INP_LOCK(inp);
673 if (inp->inp_moptions != NULL)
674 return (inp->inp_moptions);
675
676 INP_UNLOCK(inp);
677
678 imo = (struct ip_moptions *)malloc(sizeof(*imo), M_IPMOPTS,
679 M_WAITOK);
680 immp = (struct in_multi **)malloc(sizeof(*immp) * IP_MIN_MEMBERSHIPS,
681 M_IPMOPTS, M_WAITOK | M_ZERO);
682 imfp = (struct in_mfilter *)malloc(
683 sizeof(struct in_mfilter) * IP_MIN_MEMBERSHIPS,
684 M_IPMSOURCE, M_WAITOK);
685
686 imo->imo_multicast_ifp = NULL;
687 imo->imo_multicast_addr.s_addr = INADDR_ANY;
688 imo->imo_multicast_vif = -1;
689 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
690 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
691 imo->imo_num_memberships = 0;
692 imo->imo_max_memberships = IP_MIN_MEMBERSHIPS;
693 imo->imo_membership = immp;
694
695 /* Initialize per-group source filters. */
696 for (idx = 0; idx < IP_MIN_MEMBERSHIPS; idx++) {
697 imfp[idx].imf_fmode = MCAST_EXCLUDE;
698 imfp[idx].imf_nsources = 0;
699 TAILQ_INIT(&imfp[idx].imf_sources);
700 }
701 imo->imo_mfilters = imfp;
702
703 INP_LOCK(inp);
704 if (inp->inp_moptions != NULL) {
705 free(imfp, M_IPMSOURCE);
706 free(immp, M_IPMOPTS);
707 free(imo, M_IPMOPTS);
708 return (inp->inp_moptions);
709 }
710 inp->inp_moptions = imo;
711 return (imo);
712 }
713
714 /*
715 * Discard the IP multicast options (and source filters).
716 */
717 void
718 inp_freemoptions(struct ip_moptions *imo)
719 {
720 struct in_mfilter *imf;
721 struct in_msource *ims, *tims;
722 size_t idx, nmships;
723
724 KASSERT(imo != NULL, ("%s: ip_moptions is NULL", __func__));
725
726 nmships = imo->imo_num_memberships;
727 for (idx = 0; idx < nmships; ++idx) {
728 in_delmulti(imo->imo_membership[idx]);
729
730 if (imo->imo_mfilters != NULL) {
731 imf = &imo->imo_mfilters[idx];
732 TAILQ_FOREACH_SAFE(ims, &imf->imf_sources,
733 ims_next, tims) {
734 TAILQ_REMOVE(&imf->imf_sources, ims, ims_next);
735 FREE(ims, M_IPMSOURCE);
736 imf->imf_nsources--;
737 }
738 KASSERT(imf->imf_nsources == 0,
739 ("%s: did not free all imf_nsources", __func__));
740 }
741 }
742
743 if (imo->imo_mfilters != NULL)
744 free(imo->imo_mfilters, M_IPMSOURCE);
745 free(imo->imo_membership, M_IPMOPTS);
746 free(imo, M_IPMOPTS);
747 }
748
749 /*
750 * Atomically get source filters on a socket for an IPv4 multicast group.
751 * Called with INP lock held; returns with lock released.
752 */
753 static int
754 inp_get_source_filters(struct inpcb *inp, struct sockopt *sopt)
755 {
756 struct __msfilterreq msfr;
757 sockunion_t *gsa;
758 struct ifnet *ifp;
759 struct ip_moptions *imo;
760 struct in_mfilter *imf;
761 struct in_msource *ims;
762 struct sockaddr_storage *ptss;
763 struct sockaddr_storage *tss;
764 int error;
765 size_t idx;
766
767 INP_LOCK_ASSERT(inp);
768
769 imo = inp->inp_moptions;
770 KASSERT(imo != NULL, ("%s: null ip_moptions", __func__));
771
772 INP_UNLOCK(inp);
773
774 error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
775 sizeof(struct __msfilterreq));
776 if (error)
777 return (error);
778
779 if (msfr.msfr_ifindex == 0 || if_index < msfr.msfr_ifindex)
780 return (EINVAL);
781
782 ifp = ifnet_byindex(msfr.msfr_ifindex);
783 if (ifp == NULL)
784 return (EINVAL);
785
786 INP_LOCK(inp);
787
788 /*
789 * Lookup group on the socket.
790 */
791 gsa = (sockunion_t *)&msfr.msfr_group;
792 idx = imo_match_group(imo, ifp, &gsa->sa);
793 if (idx == -1 || imo->imo_mfilters == NULL) {
794 INP_UNLOCK(inp);
795 return (EADDRNOTAVAIL);
796 }
797
798 imf = &imo->imo_mfilters[idx];
799 msfr.msfr_fmode = imf->imf_fmode;
800 msfr.msfr_nsrcs = imf->imf_nsources;
801
802 /*
803 * If the user specified a buffer, copy out the source filter
804 * entries to userland gracefully.
805 * msfr.msfr_nsrcs is always set to the total number of filter
806 * entries which the kernel currently has for this group.
807 */
808 tss = NULL;
809 if (msfr.msfr_srcs != NULL && msfr.msfr_nsrcs > 0) {
810 /*
811 * Make a copy of the source vector so that we do not
812 * thrash the inpcb lock whilst copying it out.
813 * We only copy out the number of entries which userland
814 * has asked for, but we always tell userland how big the
815 * buffer really needs to be.
816 */
817 MALLOC(tss, struct sockaddr_storage *,
818 sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
819 M_TEMP, M_NOWAIT);
820 if (tss == NULL) {
821 error = ENOBUFS;
822 } else {
823 ptss = tss;
824 TAILQ_FOREACH(ims, &imf->imf_sources, ims_next) {
825 memcpy(ptss++, &ims->ims_addr,
826 sizeof(struct sockaddr_storage));
827 }
828 }
829 }
830
831 INP_UNLOCK(inp);
832
833 if (tss != NULL) {
834 error = copyout(tss, msfr.msfr_srcs,
835 sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
836 FREE(tss, M_TEMP);
837 }
838
839 if (error)
840 return (error);
841
842 error = sooptcopyout(sopt, &msfr, sizeof(struct __msfilterreq));
843
844 return (error);
845 }
846
847 /*
848 * Return the IP multicast options in response to user getsockopt().
849 */
850 int
851 inp_getmoptions(struct inpcb *inp, struct sockopt *sopt)
852 {
853 struct ip_mreqn mreqn;
854 struct ip_moptions *imo;
855 struct ifnet *ifp;
856 struct in_ifaddr *ia;
857 int error, optval;
858 u_char coptval;
859
860 INP_LOCK(inp);
861 imo = inp->inp_moptions;
862 /*
863 * If socket is neither of type SOCK_RAW or SOCK_DGRAM,
864 * or is a divert socket, reject it.
865 */
866 if (inp->inp_socket->so_proto->pr_protocol == IPPROTO_DIVERT ||
867 (inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
868 inp->inp_socket->so_proto->pr_type != SOCK_DGRAM)) {
869 INP_UNLOCK(inp);
870 return (EOPNOTSUPP);
871 }
872
873 error = 0;
874 switch (sopt->sopt_name) {
875 case IP_MULTICAST_VIF:
876 if (imo != NULL)
877 optval = imo->imo_multicast_vif;
878 else
879 optval = -1;
880 INP_UNLOCK(inp);
881 error = sooptcopyout(sopt, &optval, sizeof(int));
882 break;
883
884 case IP_MULTICAST_IF:
885 memset(&mreqn, 0, sizeof(struct ip_mreqn));
886 if (imo != NULL) {
887 ifp = imo->imo_multicast_ifp;
888 if (imo->imo_multicast_addr.s_addr != INADDR_ANY) {
889 mreqn.imr_address = imo->imo_multicast_addr;
890 } else if (ifp != NULL) {
891 mreqn.imr_ifindex = ifp->if_index;
892 IFP_TO_IA(ifp, ia);
893 if (ia != NULL) {
894 mreqn.imr_address =
895 IA_SIN(ia)->sin_addr;
896 }
897 }
898 }
899 INP_UNLOCK(inp);
900 if (sopt->sopt_valsize == sizeof(struct ip_mreqn)) {
901 error = sooptcopyout(sopt, &mreqn,
902 sizeof(struct ip_mreqn));
903 } else {
904 error = sooptcopyout(sopt, &mreqn.imr_address,
905 sizeof(struct in_addr));
906 }
907 break;
908
909 case IP_MULTICAST_TTL:
910 if (imo == 0)
911 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
912 else
913 optval = coptval = imo->imo_multicast_ttl;
914 INP_UNLOCK(inp);
915 if (sopt->sopt_valsize == sizeof(u_char))
916 error = sooptcopyout(sopt, &coptval, sizeof(u_char));
917 else
918 error = sooptcopyout(sopt, &optval, sizeof(int));
919 break;
920
921 case IP_MULTICAST_LOOP:
922 if (imo == 0)
923 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
924 else
925 optval = coptval = imo->imo_multicast_loop;
926 INP_UNLOCK(inp);
927 if (sopt->sopt_valsize == sizeof(u_char))
928 error = sooptcopyout(sopt, &coptval, sizeof(u_char));
929 else
930 error = sooptcopyout(sopt, &optval, sizeof(int));
931 break;
932
933 case IP_MSFILTER:
934 if (imo == NULL) {
935 error = EADDRNOTAVAIL;
936 INP_UNLOCK(inp);
937 } else {
938 error = inp_get_source_filters(inp, sopt);
939 }
940 break;
941
942 default:
943 INP_UNLOCK(inp);
944 error = ENOPROTOOPT;
945 break;
946 }
947
948 INP_UNLOCK_ASSERT(inp);
949
950 return (error);
951 }
952
953 /*
954 * Join an IPv4 multicast group, possibly with a source.
955 */
956 static int
957 inp_join_group(struct inpcb *inp, struct sockopt *sopt)
958 {
959 struct group_source_req gsr;
960 sockunion_t *gsa, *ssa;
961 struct ifnet *ifp;
962 struct in_mfilter *imf;
963 struct ip_moptions *imo;
964 struct in_multi *inm;
965 size_t idx;
966 int error;
967
968 ifp = NULL;
969 error = 0;
970
971 memset(&gsr, 0, sizeof(struct group_source_req));
972 gsa = (sockunion_t *)&gsr.gsr_group;
973 gsa->ss.ss_family = AF_UNSPEC;
974 ssa = (sockunion_t *)&gsr.gsr_source;
975 ssa->ss.ss_family = AF_UNSPEC;
976
977 switch (sopt->sopt_name) {
978 case IP_ADD_MEMBERSHIP:
979 case IP_ADD_SOURCE_MEMBERSHIP: {
980 struct ip_mreq_source mreqs;
981
982 if (sopt->sopt_name == IP_ADD_MEMBERSHIP) {
983 error = sooptcopyin(sopt, &mreqs,
984 sizeof(struct ip_mreq),
985 sizeof(struct ip_mreq));
986 /*
987 * Do argument switcharoo from ip_mreq into
988 * ip_mreq_source to avoid using two instances.
989 */
990 mreqs.imr_interface = mreqs.imr_sourceaddr;
991 mreqs.imr_sourceaddr.s_addr = INADDR_ANY;
992 } else if (sopt->sopt_name == IP_ADD_SOURCE_MEMBERSHIP) {
993 error = sooptcopyin(sopt, &mreqs,
994 sizeof(struct ip_mreq_source),
995 sizeof(struct ip_mreq_source));
996 }
997 if (error)
998 return (error);
999
1000 gsa->sin.sin_family = AF_INET;
1001 gsa->sin.sin_len = sizeof(struct sockaddr_in);
1002 gsa->sin.sin_addr = mreqs.imr_multiaddr;
1003
1004 if (sopt->sopt_name == IP_ADD_SOURCE_MEMBERSHIP) {
1005 ssa->sin.sin_family = AF_INET;
1006 ssa->sin.sin_len = sizeof(struct sockaddr_in);
1007 ssa->sin.sin_addr = mreqs.imr_sourceaddr;
1008 }
1009
1010 /*
1011 * Obtain ifp. If no interface address was provided,
1012 * use the interface of the route in the unicast FIB for
1013 * the given multicast destination; usually, this is the
1014 * default route.
1015 * If this lookup fails, attempt to use the first non-loopback
1016 * interface with multicast capability in the system as a
1017 * last resort. The legacy IPv4 ASM API requires that we do
1018 * this in order to allow groups to be joined when the routing
1019 * table has not yet been populated during boot.
1020 * If all of these conditions fail, return EADDRNOTAVAIL, and
1021 * reject the IPv4 multicast join.
1022 */
1023 if (mreqs.imr_interface.s_addr != INADDR_ANY) {
1024 ifp = ip_multicast_if(&mreqs.imr_interface);
1025 } else {
1026 struct route ro;
1027
1028 ro.ro_rt = NULL;
1029 *(struct sockaddr_in *)&ro.ro_dst = gsa->sin;
1030 rtalloc_ign(&ro, RTF_CLONING);
1031 if (ro.ro_rt != NULL) {
1032 ifp = ro.ro_rt->rt_ifp;
1033 KASSERT(ifp != NULL, ("%s: null ifp",
1034 __func__));
1035 RTFREE(ro.ro_rt);
1036 } else {
1037 struct in_ifaddr *ia;
1038 struct ifnet *mfp = NULL;
1039 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) {
1040 mfp = ia->ia_ifp;
1041 if (!(mfp->if_flags & IFF_LOOPBACK) &&
1042 (mfp->if_flags & IFF_MULTICAST)) {
1043 ifp = mfp;
1044 break;
1045 }
1046 }
1047 }
1048 }
1049 #ifdef DIAGNOSTIC
1050 if (bootverbose) {
1051 printf("%s: imr_interface = %s, ifp = %p\n",
1052 __func__, inet_ntoa(mreqs.imr_interface), ifp);
1053 }
1054 #endif
1055 break;
1056 }
1057
1058 case MCAST_JOIN_GROUP:
1059 case MCAST_JOIN_SOURCE_GROUP:
1060 if (sopt->sopt_name == MCAST_JOIN_GROUP) {
1061 error = sooptcopyin(sopt, &gsr,
1062 sizeof(struct group_req),
1063 sizeof(struct group_req));
1064 } else if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
1065 error = sooptcopyin(sopt, &gsr,
1066 sizeof(struct group_source_req),
1067 sizeof(struct group_source_req));
1068 }
1069 if (error)
1070 return (error);
1071
1072 if (gsa->sin.sin_family != AF_INET ||
1073 gsa->sin.sin_len != sizeof(struct sockaddr_in))
1074 return (EINVAL);
1075
1076 /*
1077 * Overwrite the port field if present, as the sockaddr
1078 * being copied in may be matched with a binary comparison.
1079 * XXX INET6
1080 */
1081 gsa->sin.sin_port = 0;
1082 if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
1083 if (ssa->sin.sin_family != AF_INET ||
1084 ssa->sin.sin_len != sizeof(struct sockaddr_in))
1085 return (EINVAL);
1086 ssa->sin.sin_port = 0;
1087 }
1088
1089 /*
1090 * Obtain the ifp.
1091 */
1092 if (gsr.gsr_interface == 0 || if_index < gsr.gsr_interface)
1093 return (EADDRNOTAVAIL);
1094 ifp = ifnet_byindex(gsr.gsr_interface);
1095
1096 break;
1097
1098 default:
1099 #ifdef DIAGNOSTIC
1100 if (bootverbose) {
1101 printf("%s: unknown sopt_name %d\n", __func__,
1102 sopt->sopt_name);
1103 }
1104 #endif
1105 return (EOPNOTSUPP);
1106 break;
1107 }
1108
1109 if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1110 return (EINVAL);
1111
1112 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0)
1113 return (EADDRNOTAVAIL);
1114
1115 /*
1116 * Check if we already hold membership of this group for this inpcb.
1117 * If so, we do not need to perform the initial join.
1118 */
1119 imo = inp_findmoptions(inp);
1120 idx = imo_match_group(imo, ifp, &gsa->sa);
1121 if (idx != -1) {
1122 if (ssa->ss.ss_family != AF_UNSPEC) {
1123 /*
1124 * Attempting to join an ASM group (when already
1125 * an ASM or SSM member) is an error.
1126 */
1127 error = EADDRNOTAVAIL;
1128 } else {
1129 imf = &imo->imo_mfilters[idx];
1130 if (imf->imf_nsources == 0) {
1131 /*
1132 * Attempting to join an SSM group (when
1133 * already an ASM member) is an error.
1134 */
1135 error = EINVAL;
1136 } else {
1137 /*
1138 * Attempting to join an SSM group (when
1139 * already an SSM member) means "add this
1140 * source to the inclusive filter list".
1141 */
1142 error = imo_join_source(imo, idx, ssa);
1143 }
1144 }
1145 goto out_locked;
1146 }
1147
1148 /*
1149 * Call imo_grow() to reallocate the membership and source filter
1150 * vectors if they are full. If the size would exceed the hard limit,
1151 * then we know we've really run out of entries. We keep the INP
1152 * lock held to avoid introducing a race condition.
1153 */
1154 if (imo->imo_num_memberships == imo->imo_max_memberships) {
1155 error = imo_grow(imo);
1156 if (error)
1157 goto out_locked;
1158 }
1159
1160 /*
1161 * So far, so good: perform the layer 3 join, layer 2 join,
1162 * and make an IGMP announcement if needed.
1163 */
1164 inm = in_addmulti(&gsa->sin.sin_addr, ifp);
1165 if (inm == NULL) {
1166 error = ENOBUFS;
1167 goto out_locked;
1168 }
1169 idx = imo->imo_num_memberships;
1170 imo->imo_membership[idx] = inm;
1171 imo->imo_num_memberships++;
1172
1173 KASSERT(imo->imo_mfilters != NULL,
1174 ("%s: imf_mfilters vector was not allocated", __func__));
1175 imf = &imo->imo_mfilters[idx];
1176 KASSERT(TAILQ_EMPTY(&imf->imf_sources),
1177 ("%s: imf_sources not empty", __func__));
1178
1179 /*
1180 * If this is a new SSM group join (i.e. a source was specified
1181 * with this group), add this source to the filter list.
1182 */
1183 if (ssa->ss.ss_family != AF_UNSPEC) {
1184 /*
1185 * An initial SSM join implies that this socket's membership
1186 * of the multicast group is now in inclusive mode.
1187 */
1188 imf->imf_fmode = MCAST_INCLUDE;
1189
1190 error = imo_join_source(imo, idx, ssa);
1191 if (error) {
1192 /*
1193 * Drop inp lock before calling in_delmulti(),
1194 * to prevent a lock order reversal.
1195 */
1196 --imo->imo_num_memberships;
1197 INP_UNLOCK(inp);
1198 in_delmulti(inm);
1199 return (error);
1200 }
1201 }
1202
1203 out_locked:
1204 INP_UNLOCK(inp);
1205 return (error);
1206 }
1207
1208 /*
1209 * Leave an IPv4 multicast group on an inpcb, possibly with a source.
1210 */
1211 static int
1212 inp_leave_group(struct inpcb *inp, struct sockopt *sopt)
1213 {
1214 struct group_source_req gsr;
1215 struct ip_mreq_source mreqs;
1216 sockunion_t *gsa, *ssa;
1217 struct ifnet *ifp;
1218 struct in_mfilter *imf;
1219 struct ip_moptions *imo;
1220 struct in_msource *ims, *tims;
1221 struct in_multi *inm;
1222 size_t idx;
1223 int error;
1224
1225 ifp = NULL;
1226 error = 0;
1227
1228 memset(&gsr, 0, sizeof(struct group_source_req));
1229 gsa = (sockunion_t *)&gsr.gsr_group;
1230 gsa->ss.ss_family = AF_UNSPEC;
1231 ssa = (sockunion_t *)&gsr.gsr_source;
1232 ssa->ss.ss_family = AF_UNSPEC;
1233
1234 switch (sopt->sopt_name) {
1235 case IP_DROP_MEMBERSHIP:
1236 case IP_DROP_SOURCE_MEMBERSHIP:
1237 if (sopt->sopt_name == IP_DROP_MEMBERSHIP) {
1238 error = sooptcopyin(sopt, &mreqs,
1239 sizeof(struct ip_mreq),
1240 sizeof(struct ip_mreq));
1241 /*
1242 * Swap interface and sourceaddr arguments,
1243 * as ip_mreq and ip_mreq_source are laid
1244 * out differently.
1245 */
1246 mreqs.imr_interface = mreqs.imr_sourceaddr;
1247 mreqs.imr_sourceaddr.s_addr = INADDR_ANY;
1248 } else if (sopt->sopt_name == IP_DROP_SOURCE_MEMBERSHIP) {
1249 error = sooptcopyin(sopt, &mreqs,
1250 sizeof(struct ip_mreq_source),
1251 sizeof(struct ip_mreq_source));
1252 }
1253 if (error)
1254 return (error);
1255
1256 gsa->sin.sin_family = AF_INET;
1257 gsa->sin.sin_len = sizeof(struct sockaddr_in);
1258 gsa->sin.sin_addr = mreqs.imr_multiaddr;
1259
1260 if (sopt->sopt_name == IP_DROP_SOURCE_MEMBERSHIP) {
1261 ssa->sin.sin_family = AF_INET;
1262 ssa->sin.sin_len = sizeof(struct sockaddr_in);
1263 ssa->sin.sin_addr = mreqs.imr_sourceaddr;
1264 }
1265
1266 if (gsa->sin.sin_addr.s_addr != INADDR_ANY)
1267 INADDR_TO_IFP(mreqs.imr_interface, ifp);
1268
1269 #ifdef DIAGNOSTIC
1270 if (bootverbose) {
1271 printf("%s: imr_interface = %s, ifp = %p\n",
1272 __func__, inet_ntoa(mreqs.imr_interface), ifp);
1273 }
1274 #endif
1275 break;
1276
1277 case MCAST_LEAVE_GROUP:
1278 case MCAST_LEAVE_SOURCE_GROUP:
1279 if (sopt->sopt_name == MCAST_LEAVE_GROUP) {
1280 error = sooptcopyin(sopt, &gsr,
1281 sizeof(struct group_req),
1282 sizeof(struct group_req));
1283 } else if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
1284 error = sooptcopyin(sopt, &gsr,
1285 sizeof(struct group_source_req),
1286 sizeof(struct group_source_req));
1287 }
1288 if (error)
1289 return (error);
1290
1291 if (gsa->sin.sin_family != AF_INET ||
1292 gsa->sin.sin_len != sizeof(struct sockaddr_in))
1293 return (EINVAL);
1294
1295 if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
1296 if (ssa->sin.sin_family != AF_INET ||
1297 ssa->sin.sin_len != sizeof(struct sockaddr_in))
1298 return (EINVAL);
1299 }
1300
1301 if (gsr.gsr_interface == 0 || if_index < gsr.gsr_interface)
1302 return (EADDRNOTAVAIL);
1303
1304 ifp = ifnet_byindex(gsr.gsr_interface);
1305 break;
1306
1307 default:
1308 #ifdef DIAGNOSTIC
1309 if (bootverbose) {
1310 printf("%s: unknown sopt_name %d\n", __func__,
1311 sopt->sopt_name);
1312 }
1313 #endif
1314 return (EOPNOTSUPP);
1315 break;
1316 }
1317
1318 if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1319 return (EINVAL);
1320
1321 /*
1322 * Find the membership in the membership array.
1323 */
1324 imo = inp_findmoptions(inp);
1325 idx = imo_match_group(imo, ifp, &gsa->sa);
1326 if (idx == -1) {
1327 error = EADDRNOTAVAIL;
1328 goto out_locked;
1329 }
1330 imf = &imo->imo_mfilters[idx];
1331
1332 /*
1333 * If we were instructed only to leave a given source, do so.
1334 */
1335 if (ssa->ss.ss_family != AF_UNSPEC) {
1336 if (imf->imf_nsources == 0 ||
1337 imf->imf_fmode == MCAST_EXCLUDE) {
1338 /*
1339 * Attempting to SSM leave an ASM group
1340 * is an error; should use *_BLOCK_SOURCE instead.
1341 * Attempting to SSM leave a source in a group when
1342 * the socket is in 'exclude mode' is also an error.
1343 */
1344 error = EINVAL;
1345 } else {
1346 error = imo_leave_source(imo, idx, ssa);
1347 }
1348 /*
1349 * If an error occurred, or this source is not the last
1350 * source in the group, do not leave the whole group.
1351 */
1352 if (error || imf->imf_nsources > 0)
1353 goto out_locked;
1354 }
1355
1356 /*
1357 * Give up the multicast address record to which the membership points.
1358 */
1359 inm = imo->imo_membership[idx];
1360 in_delmulti(inm);
1361
1362 /*
1363 * Free any source filters for this group if they exist.
1364 * Revert inpcb to the default MCAST_EXCLUDE state.
1365 */
1366 if (imo->imo_mfilters != NULL) {
1367 TAILQ_FOREACH_SAFE(ims, &imf->imf_sources, ims_next, tims) {
1368 TAILQ_REMOVE(&imf->imf_sources, ims, ims_next);
1369 FREE(ims, M_IPMSOURCE);
1370 imf->imf_nsources--;
1371 }
1372 KASSERT(imf->imf_nsources == 0,
1373 ("%s: imf_nsources not 0", __func__));
1374 KASSERT(TAILQ_EMPTY(&imf->imf_sources),
1375 ("%s: imf_sources not empty", __func__));
1376 imf->imf_fmode = MCAST_EXCLUDE;
1377 }
1378
1379 /*
1380 * Remove the gap in the membership array.
1381 */
1382 for (++idx; idx < imo->imo_num_memberships; ++idx)
1383 imo->imo_membership[idx-1] = imo->imo_membership[idx];
1384 imo->imo_num_memberships--;
1385
1386 out_locked:
1387 INP_UNLOCK(inp);
1388 return (error);
1389 }
1390
1391 /*
1392 * Select the interface for transmitting IPv4 multicast datagrams.
1393 *
1394 * Either an instance of struct in_addr or an instance of struct ip_mreqn
1395 * may be passed to this socket option. An address of INADDR_ANY or an
1396 * interface index of 0 is used to remove a previous selection.
1397 * When no interface is selected, one is chosen for every send.
1398 */
1399 static int
1400 inp_set_multicast_if(struct inpcb *inp, struct sockopt *sopt)
1401 {
1402 struct in_addr addr;
1403 struct ip_mreqn mreqn;
1404 struct ifnet *ifp;
1405 struct ip_moptions *imo;
1406 int error;
1407
1408 if (sopt->sopt_valsize == sizeof(struct ip_mreqn)) {
1409 /*
1410 * An interface index was specified using the
1411 * Linux-derived ip_mreqn structure.
1412 */
1413 error = sooptcopyin(sopt, &mreqn, sizeof(struct ip_mreqn),
1414 sizeof(struct ip_mreqn));
1415 if (error)
1416 return (error);
1417
1418 if (mreqn.imr_ifindex < 0 || if_index < mreqn.imr_ifindex)
1419 return (EINVAL);
1420
1421 if (mreqn.imr_ifindex == 0) {
1422 ifp = NULL;
1423 } else {
1424 ifp = ifnet_byindex(mreqn.imr_ifindex);
1425 if (ifp == NULL)
1426 return (EADDRNOTAVAIL);
1427 }
1428 } else {
1429 /*
1430 * An interface was specified by IPv4 address.
1431 * This is the traditional BSD usage.
1432 */
1433 error = sooptcopyin(sopt, &addr, sizeof(struct in_addr),
1434 sizeof(struct in_addr));
1435 if (error)
1436 return (error);
1437 if (addr.s_addr == INADDR_ANY) {
1438 ifp = NULL;
1439 } else {
1440 ifp = ip_multicast_if(&addr);
1441 if (ifp == NULL)
1442 return (EADDRNOTAVAIL);
1443 }
1444 #ifdef DIAGNOSTIC
1445 if (bootverbose) {
1446 printf("%s: ifp = %p, addr = %s\n",
1447 __func__, ifp, inet_ntoa(addr)); /* XXX INET6 */
1448 }
1449 #endif
1450 }
1451
1452 /* Reject interfaces which do not support multicast. */
1453 if (ifp != NULL && (ifp->if_flags & IFF_MULTICAST) == 0)
1454 return (EOPNOTSUPP);
1455
1456 imo = inp_findmoptions(inp);
1457 imo->imo_multicast_ifp = ifp;
1458 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1459 INP_UNLOCK(inp);
1460
1461 return (0);
1462 }
1463
1464 /*
1465 * Atomically set source filters on a socket for an IPv4 multicast group.
1466 */
1467 static int
1468 inp_set_source_filters(struct inpcb *inp, struct sockopt *sopt)
1469 {
1470 struct __msfilterreq msfr;
1471 sockunion_t *gsa;
1472 struct ifnet *ifp;
1473 struct in_mfilter *imf;
1474 struct ip_moptions *imo;
1475 struct in_msource *ims, *tims;
1476 size_t idx;
1477 int error;
1478
1479 error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
1480 sizeof(struct __msfilterreq));
1481 if (error)
1482 return (error);
1483
1484 if (msfr.msfr_nsrcs > IP_MAX_SOURCE_FILTER ||
1485 (msfr.msfr_fmode != MCAST_EXCLUDE &&
1486 msfr.msfr_fmode != MCAST_INCLUDE))
1487 return (EINVAL);
1488
1489 if (msfr.msfr_group.ss_family != AF_INET ||
1490 msfr.msfr_group.ss_len != sizeof(struct sockaddr_in))
1491 return (EINVAL);
1492
1493 gsa = (sockunion_t *)&msfr.msfr_group;
1494 if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1495 return (EINVAL);
1496
1497 gsa->sin.sin_port = 0; /* ignore port */
1498
1499 if (msfr.msfr_ifindex == 0 || if_index < msfr.msfr_ifindex)
1500 return (EADDRNOTAVAIL);
1501
1502 ifp = ifnet_byindex(msfr.msfr_ifindex);
1503 if (ifp == NULL)
1504 return (EADDRNOTAVAIL);
1505
1506 /*
1507 * Take the INP lock.
1508 * Check if this socket is a member of this group.
1509 */
1510 imo = inp_findmoptions(inp);
1511 idx = imo_match_group(imo, ifp, &gsa->sa);
1512 if (idx == -1 || imo->imo_mfilters == NULL) {
1513 error = EADDRNOTAVAIL;
1514 goto out_locked;
1515 }
1516 imf = &imo->imo_mfilters[idx];
1517
1518 #ifdef DIAGNOSTIC
1519 if (bootverbose)
1520 printf("%s: clearing source list\n", __func__);
1521 #endif
1522
1523 /*
1524 * Remove any existing source filters.
1525 */
1526 TAILQ_FOREACH_SAFE(ims, &imf->imf_sources, ims_next, tims) {
1527 TAILQ_REMOVE(&imf->imf_sources, ims, ims_next);
1528 FREE(ims, M_IPMSOURCE);
1529 imf->imf_nsources--;
1530 }
1531 KASSERT(imf->imf_nsources == 0,
1532 ("%s: source list not cleared", __func__));
1533
1534 /*
1535 * Apply any new source filters, if present.
1536 */
1537 if (msfr.msfr_nsrcs > 0) {
1538 struct in_msource **pnims;
1539 struct in_msource *nims;
1540 struct sockaddr_storage *kss;
1541 struct sockaddr_storage *pkss;
1542 sockunion_t *psu;
1543 int i, j;
1544
1545 /*
1546 * Drop the inp lock so we may sleep if we need to
1547 * in order to satisfy a malloc request.
1548 * We will re-take it before changing socket state.
1549 */
1550 INP_UNLOCK(inp);
1551 #ifdef DIAGNOSTIC
1552 if (bootverbose) {
1553 printf("%s: loading %lu source list entries\n",
1554 __func__, (unsigned long)msfr.msfr_nsrcs);
1555 }
1556 #endif
1557 /*
1558 * Make a copy of the user-space source vector so
1559 * that we may copy them with a single copyin. This
1560 * allows us to deal with page faults up-front.
1561 */
1562 MALLOC(kss, struct sockaddr_storage *,
1563 sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
1564 M_TEMP, M_WAITOK);
1565 error = copyin(msfr.msfr_srcs, kss,
1566 sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
1567 if (error) {
1568 FREE(kss, M_TEMP);
1569 return (error);
1570 }
1571
1572 /*
1573 * Perform argument checking on every sockaddr_storage
1574 * structure in the vector provided to us. Overwrite
1575 * fields which should not apply to source entries.
1576 * TODO: Check for duplicate sources on this pass.
1577 */
1578 psu = (sockunion_t *)kss;
1579 for (i = 0; i < msfr.msfr_nsrcs; i++, psu++) {
1580 switch (psu->ss.ss_family) {
1581 case AF_INET:
1582 if (psu->sin.sin_len !=
1583 sizeof(struct sockaddr_in)) {
1584 error = EINVAL;
1585 } else {
1586 psu->sin.sin_port = 0;
1587 }
1588 break;
1589 #ifdef notyet
1590 case AF_INET6;
1591 if (psu->sin6.sin6_len !=
1592 sizeof(struct sockaddr_in6)) {
1593 error = EINVAL;
1594 } else {
1595 psu->sin6.sin6_port = 0;
1596 psu->sin6.sin6_flowinfo = 0;
1597 }
1598 break;
1599 #endif
1600 default:
1601 error = EAFNOSUPPORT;
1602 break;
1603 }
1604 if (error)
1605 break;
1606 }
1607 if (error) {
1608 FREE(kss, M_TEMP);
1609 return (error);
1610 }
1611
1612 /*
1613 * Allocate a block to track all the in_msource
1614 * entries we are about to allocate, in case we
1615 * abruptly need to free them.
1616 */
1617 MALLOC(pnims, struct in_msource **,
1618 sizeof(struct in_msource *) * msfr.msfr_nsrcs,
1619 M_TEMP, M_WAITOK | M_ZERO);
1620
1621 /*
1622 * Allocate up to nsrcs individual chunks.
1623 * If we encounter an error, backtrack out of
1624 * all allocations cleanly; updates must be atomic.
1625 */
1626 pkss = kss;
1627 nims = NULL;
1628 for (i = 0; i < msfr.msfr_nsrcs; i++, pkss++) {
1629 MALLOC(nims, struct in_msource *,
1630 sizeof(struct in_msource) * msfr.msfr_nsrcs,
1631 M_IPMSOURCE, M_WAITOK | M_ZERO);
1632 pnims[i] = nims;
1633 }
1634 if (i < msfr.msfr_nsrcs) {
1635 for (j = 0; j < i; j++) {
1636 if (pnims[j] != NULL)
1637 FREE(pnims[j], M_IPMSOURCE);
1638 }
1639 FREE(pnims, M_TEMP);
1640 FREE(kss, M_TEMP);
1641 return (ENOBUFS);
1642 }
1643
1644 INP_UNLOCK_ASSERT(inp);
1645
1646 /*
1647 * Finally, apply the filters to the socket.
1648 * Re-take the inp lock; we are changing socket state.
1649 */
1650 pkss = kss;
1651 INP_LOCK(inp);
1652 for (i = 0; i < msfr.msfr_nsrcs; i++, pkss++) {
1653 memcpy(&(pnims[i]->ims_addr), pkss,
1654 sizeof(struct sockaddr_storage));
1655 TAILQ_INSERT_TAIL(&imf->imf_sources, pnims[i],
1656 ims_next);
1657 imf->imf_nsources++;
1658 }
1659 FREE(pnims, M_TEMP);
1660 FREE(kss, M_TEMP);
1661 }
1662
1663 /*
1664 * Update the filter mode on the socket before releasing the inpcb.
1665 */
1666 INP_LOCK_ASSERT(inp);
1667 imf->imf_fmode = msfr.msfr_fmode;
1668
1669 out_locked:
1670 INP_UNLOCK(inp);
1671 return (error);
1672 }
1673
1674 /*
1675 * Set the IP multicast options in response to user setsockopt().
1676 *
1677 * Many of the socket options handled in this function duplicate the
1678 * functionality of socket options in the regular unicast API. However,
1679 * it is not possible to merge the duplicate code, because the idempotence
1680 * of the IPv4 multicast part of the BSD Sockets API must be preserved;
1681 * the effects of these options must be treated as separate and distinct.
1682 */
1683 int
1684 inp_setmoptions(struct inpcb *inp, struct sockopt *sopt)
1685 {
1686 struct ip_moptions *imo;
1687 int error;
1688
1689 error = 0;
1690
1691 /*
1692 * If socket is neither of type SOCK_RAW or SOCK_DGRAM,
1693 * or is a divert socket, reject it.
1694 * XXX Unlocked read of inp_socket believed OK.
1695 */
1696 if (inp->inp_socket->so_proto->pr_protocol == IPPROTO_DIVERT ||
1697 (inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
1698 inp->inp_socket->so_proto->pr_type != SOCK_DGRAM))
1699 return (EOPNOTSUPP);
1700
1701 switch (sopt->sopt_name) {
1702 case IP_MULTICAST_VIF: {
1703 int vifi;
1704 /*
1705 * Select a multicast VIF for transmission.
1706 * Only useful if multicast forwarding is active.
1707 */
1708 if (legal_vif_num == NULL) {
1709 error = EOPNOTSUPP;
1710 break;
1711 }
1712 error = sooptcopyin(sopt, &vifi, sizeof(int), sizeof(int));
1713 if (error)
1714 break;
1715 if (!legal_vif_num(vifi) && (vifi != -1)) {
1716 error = EINVAL;
1717 break;
1718 }
1719 imo = inp_findmoptions(inp);
1720 imo->imo_multicast_vif = vifi;
1721 INP_UNLOCK(inp);
1722 break;
1723 }
1724
1725 case IP_MULTICAST_IF:
1726 error = inp_set_multicast_if(inp, sopt);
1727 break;
1728
1729 case IP_MULTICAST_TTL: {
1730 u_char ttl;
1731
1732 /*
1733 * Set the IP time-to-live for outgoing multicast packets.
1734 * The original multicast API required a char argument,
1735 * which is inconsistent with the rest of the socket API.
1736 * We allow either a char or an int.
1737 */
1738 if (sopt->sopt_valsize == sizeof(u_char)) {
1739 error = sooptcopyin(sopt, &ttl, sizeof(u_char),
1740 sizeof(u_char));
1741 if (error)
1742 break;
1743 } else {
1744 u_int ittl;
1745
1746 error = sooptcopyin(sopt, &ittl, sizeof(u_int),
1747 sizeof(u_int));
1748 if (error)
1749 break;
1750 if (ittl > 255) {
1751 error = EINVAL;
1752 break;
1753 }
1754 ttl = (u_char)ittl;
1755 }
1756 imo = inp_findmoptions(inp);
1757 imo->imo_multicast_ttl = ttl;
1758 INP_UNLOCK(inp);
1759 break;
1760 }
1761
1762 case IP_MULTICAST_LOOP: {
1763 u_char loop;
1764
1765 /*
1766 * Set the loopback flag for outgoing multicast packets.
1767 * Must be zero or one. The original multicast API required a
1768 * char argument, which is inconsistent with the rest
1769 * of the socket API. We allow either a char or an int.
1770 */
1771 if (sopt->sopt_valsize == sizeof(u_char)) {
1772 error = sooptcopyin(sopt, &loop, sizeof(u_char),
1773 sizeof(u_char));
1774 if (error)
1775 break;
1776 } else {
1777 u_int iloop;
1778
1779 error = sooptcopyin(sopt, &iloop, sizeof(u_int),
1780 sizeof(u_int));
1781 if (error)
1782 break;
1783 loop = (u_char)iloop;
1784 }
1785 imo = inp_findmoptions(inp);
1786 imo->imo_multicast_loop = !!loop;
1787 INP_UNLOCK(inp);
1788 break;
1789 }
1790
1791 case IP_ADD_MEMBERSHIP:
1792 case IP_ADD_SOURCE_MEMBERSHIP:
1793 case MCAST_JOIN_GROUP:
1794 case MCAST_JOIN_SOURCE_GROUP:
1795 error = inp_join_group(inp, sopt);
1796 break;
1797
1798 case IP_DROP_MEMBERSHIP:
1799 case IP_DROP_SOURCE_MEMBERSHIP:
1800 case MCAST_LEAVE_GROUP:
1801 case MCAST_LEAVE_SOURCE_GROUP:
1802 error = inp_leave_group(inp, sopt);
1803 break;
1804
1805 case IP_BLOCK_SOURCE:
1806 case IP_UNBLOCK_SOURCE:
1807 case MCAST_BLOCK_SOURCE:
1808 case MCAST_UNBLOCK_SOURCE:
1809 error = inp_change_source_filter(inp, sopt);
1810 break;
1811
1812 case IP_MSFILTER:
1813 error = inp_set_source_filters(inp, sopt);
1814 break;
1815
1816 default:
1817 error = EOPNOTSUPP;
1818 break;
1819 }
1820
1821 INP_UNLOCK_ASSERT(inp);
1822
1823 return (error);
1824 }
1825
1826 /*
1827 * Following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1828 */
1829 static struct ifnet *
1830 ip_multicast_if(struct in_addr *a)
1831 {
1832 int ifindex;
1833 struct ifnet *ifp;
1834
1835 if (ntohl(a->s_addr) >> 24 == 0) {
1836 ifindex = ntohl(a->s_addr) & 0xffffff;
1837 if (ifindex < 0 || if_index < ifindex)
1838 return (NULL);
1839 ifp = ifnet_byindex(ifindex);
1840 } else
1841 INADDR_TO_IFP(*a, ifp);
1842 return (ifp);
1843 }
1844
Cache object: cc274f2e26a18e17e9211974aafdad57
|