1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux NET3: Internet Group Management Protocol [IGMP]
4 *
5 * This code implements the IGMP protocol as defined in RFC1112. There has
6 * been a further revision of this protocol since which is now supported.
7 *
8 * If you have trouble with this module be careful what gcc you have used,
9 * the older version didn't come out right using gcc 2.5.8, the newer one
10 * seems to fall out with gcc 2.6.2.
11 *
12 * Authors:
13 * Alan Cox <alan@lxorguk.ukuu.org.uk>
14 *
15 * Fixes:
16 *
17 * Alan Cox : Added lots of __inline__ to optimise
18 * the memory usage of all the tiny little
19 * functions.
20 * Alan Cox : Dumped the header building experiment.
21 * Alan Cox : Minor tweaks ready for multicast routing
22 * and extended IGMP protocol.
23 * Alan Cox : Removed a load of inline directives. Gcc 2.5.8
24 * writes utterly bogus code otherwise (sigh)
25 * fixed IGMP loopback to behave in the manner
26 * desired by mrouted, fixed the fact it has been
27 * broken since 1.3.6 and cleaned up a few minor
28 * points.
29 *
30 * Chih-Jen Chang : Tried to revise IGMP to Version 2
31 * Tsu-Sheng Tsao E-mail: chihjenc@scf.usc.edu and tsusheng@scf.usc.edu
32 * The enhancements are mainly based on Steve Deering's
33 * ipmulti-3.5 source code.
34 * Chih-Jen Chang : Added the igmp_get_mrouter_info and
35 * Tsu-Sheng Tsao igmp_set_mrouter_info to keep track of
36 * the mrouted version on that device.
37 * Chih-Jen Chang : Added the max_resp_time parameter to
38 * Tsu-Sheng Tsao igmp_heard_query(). Using this parameter
39 * to identify the multicast router version
40 * and do what the IGMP version 2 specified.
41 * Chih-Jen Chang : Added a timer to revert to IGMP V2 router
42 * Tsu-Sheng Tsao if the specified time expired.
43 * Alan Cox : Stop IGMP from 0.0.0.0 being accepted.
44 * Alan Cox : Use GFP_ATOMIC in the right places.
45 * Christian Daudt : igmp timer wasn't set for local group
46 * memberships but was being deleted,
47 * which caused a "del_timer() called
48 * from %p with timer not initialized\n"
49 * message (960131).
50 * Christian Daudt : removed del_timer from
51 * igmp_timer_expire function (960205).
52 * Christian Daudt : igmp_heard_report now only calls
53 * igmp_timer_expire if tm->running is
54 * true (960216).
55 * Malcolm Beattie : ttl comparison wrong in igmp_rcv made
56 * igmp_heard_query never trigger. Expiry
57 * miscalculation fixed in igmp_heard_query
58 * and random() made to return unsigned to
59 * prevent negative expiry times.
60 * Alexey Kuznetsov: Wrong group leaving behaviour, backport
61 * fix from pending 2.1.x patches.
62 * Alan Cox: Forget to enable FDDI support earlier.
63 * Alexey Kuznetsov: Fixed leaving groups on device down.
64 * Alexey Kuznetsov: Accordance to igmp-v2-06 draft.
65 * David L Stevens: IGMPv3 support, with help from
66 * Vinay Kulkarni
67 */
68
69 #include <linux/module.h>
70 #include <linux/slab.h>
71 #include <linux/uaccess.h>
72 #include <linux/types.h>
73 #include <linux/kernel.h>
74 #include <linux/jiffies.h>
75 #include <linux/string.h>
76 #include <linux/socket.h>
77 #include <linux/sockios.h>
78 #include <linux/in.h>
79 #include <linux/inet.h>
80 #include <linux/netdevice.h>
81 #include <linux/skbuff.h>
82 #include <linux/inetdevice.h>
83 #include <linux/igmp.h>
84 #include <linux/if_arp.h>
85 #include <linux/rtnetlink.h>
86 #include <linux/times.h>
87 #include <linux/pkt_sched.h>
88 #include <linux/byteorder/generic.h>
89
90 #include <net/net_namespace.h>
91 #include <net/arp.h>
92 #include <net/ip.h>
93 #include <net/protocol.h>
94 #include <net/route.h>
95 #include <net/sock.h>
96 #include <net/checksum.h>
97 #include <net/inet_common.h>
98 #include <linux/netfilter_ipv4.h>
99 #ifdef CONFIG_IP_MROUTE
100 #include <linux/mroute.h>
101 #endif
102 #ifdef CONFIG_PROC_FS
103 #include <linux/proc_fs.h>
104 #include <linux/seq_file.h>
105 #endif
106
107 #ifdef CONFIG_IP_MULTICAST
108 /* Parameter names and values are taken from igmp-v2-06 draft */
109
110 #define IGMP_QUERY_INTERVAL (125*HZ)
111 #define IGMP_QUERY_RESPONSE_INTERVAL (10*HZ)
112
113 #define IGMP_INITIAL_REPORT_DELAY (1)
114
115 /* IGMP_INITIAL_REPORT_DELAY is not from IGMP specs!
116 * IGMP specs require to report membership immediately after
117 * joining a group, but we delay the first report by a
118 * small interval. It seems more natural and still does not
119 * contradict to specs provided this delay is small enough.
120 */
121
122 #define IGMP_V1_SEEN(in_dev) \
123 (IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
124 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
125 ((in_dev)->mr_v1_seen && \
126 time_before(jiffies, (in_dev)->mr_v1_seen)))
127 #define IGMP_V2_SEEN(in_dev) \
128 (IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
129 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
130 ((in_dev)->mr_v2_seen && \
131 time_before(jiffies, (in_dev)->mr_v2_seen)))
132
133 static int unsolicited_report_interval(struct in_device *in_dev)
134 {
135 int interval_ms, interval_jiffies;
136
137 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
138 interval_ms = IN_DEV_CONF_GET(
139 in_dev,
140 IGMPV2_UNSOLICITED_REPORT_INTERVAL);
141 else /* v3 */
142 interval_ms = IN_DEV_CONF_GET(
143 in_dev,
144 IGMPV3_UNSOLICITED_REPORT_INTERVAL);
145
146 interval_jiffies = msecs_to_jiffies(interval_ms);
147
148 /* _timer functions can't handle a delay of 0 jiffies so ensure
149 * we always return a positive value.
150 */
151 if (interval_jiffies <= 0)
152 interval_jiffies = 1;
153 return interval_jiffies;
154 }
155
156 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
157 gfp_t gfp);
158 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
159 static void igmpv3_clear_delrec(struct in_device *in_dev);
160 static int sf_setstate(struct ip_mc_list *pmc);
161 static void sf_markstate(struct ip_mc_list *pmc);
162 #endif
163 static void ip_mc_clear_src(struct ip_mc_list *pmc);
164 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
165 int sfcount, __be32 *psfsrc, int delta);
166
167 static void ip_ma_put(struct ip_mc_list *im)
168 {
169 if (refcount_dec_and_test(&im->refcnt)) {
170 in_dev_put(im->interface);
171 kfree_rcu(im, rcu);
172 }
173 }
174
175 #define for_each_pmc_rcu(in_dev, pmc) \
176 for (pmc = rcu_dereference(in_dev->mc_list); \
177 pmc != NULL; \
178 pmc = rcu_dereference(pmc->next_rcu))
179
180 #define for_each_pmc_rtnl(in_dev, pmc) \
181 for (pmc = rtnl_dereference(in_dev->mc_list); \
182 pmc != NULL; \
183 pmc = rtnl_dereference(pmc->next_rcu))
184
185 static void ip_sf_list_clear_all(struct ip_sf_list *psf)
186 {
187 struct ip_sf_list *next;
188
189 while (psf) {
190 next = psf->sf_next;
191 kfree(psf);
192 psf = next;
193 }
194 }
195
196 #ifdef CONFIG_IP_MULTICAST
197
198 /*
199 * Timer management
200 */
201
202 static void igmp_stop_timer(struct ip_mc_list *im)
203 {
204 spin_lock_bh(&im->lock);
205 if (del_timer(&im->timer))
206 refcount_dec(&im->refcnt);
207 im->tm_running = 0;
208 im->reporter = 0;
209 im->unsolicit_count = 0;
210 spin_unlock_bh(&im->lock);
211 }
212
213 /* It must be called with locked im->lock */
214 static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
215 {
216 int tv = get_random_u32_below(max_delay);
217
218 im->tm_running = 1;
219 if (refcount_inc_not_zero(&im->refcnt)) {
220 if (mod_timer(&im->timer, jiffies + tv + 2))
221 ip_ma_put(im);
222 }
223 }
224
225 static void igmp_gq_start_timer(struct in_device *in_dev)
226 {
227 int tv = get_random_u32_below(in_dev->mr_maxdelay);
228 unsigned long exp = jiffies + tv + 2;
229
230 if (in_dev->mr_gq_running &&
231 time_after_eq(exp, (in_dev->mr_gq_timer).expires))
232 return;
233
234 in_dev->mr_gq_running = 1;
235 if (!mod_timer(&in_dev->mr_gq_timer, exp))
236 in_dev_hold(in_dev);
237 }
238
239 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
240 {
241 int tv = get_random_u32_below(delay);
242
243 if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
244 in_dev_hold(in_dev);
245 }
246
247 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
248 {
249 spin_lock_bh(&im->lock);
250 im->unsolicit_count = 0;
251 if (del_timer(&im->timer)) {
252 if ((long)(im->timer.expires-jiffies) < max_delay) {
253 add_timer(&im->timer);
254 im->tm_running = 1;
255 spin_unlock_bh(&im->lock);
256 return;
257 }
258 refcount_dec(&im->refcnt);
259 }
260 igmp_start_timer(im, max_delay);
261 spin_unlock_bh(&im->lock);
262 }
263
264
265 /*
266 * Send an IGMP report.
267 */
268
269 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
270
271
272 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
273 int gdeleted, int sdeleted)
274 {
275 switch (type) {
276 case IGMPV3_MODE_IS_INCLUDE:
277 case IGMPV3_MODE_IS_EXCLUDE:
278 if (gdeleted || sdeleted)
279 return 0;
280 if (!(pmc->gsquery && !psf->sf_gsresp)) {
281 if (pmc->sfmode == MCAST_INCLUDE)
282 return 1;
283 /* don't include if this source is excluded
284 * in all filters
285 */
286 if (psf->sf_count[MCAST_INCLUDE])
287 return type == IGMPV3_MODE_IS_INCLUDE;
288 return pmc->sfcount[MCAST_EXCLUDE] ==
289 psf->sf_count[MCAST_EXCLUDE];
290 }
291 return 0;
292 case IGMPV3_CHANGE_TO_INCLUDE:
293 if (gdeleted || sdeleted)
294 return 0;
295 return psf->sf_count[MCAST_INCLUDE] != 0;
296 case IGMPV3_CHANGE_TO_EXCLUDE:
297 if (gdeleted || sdeleted)
298 return 0;
299 if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
300 psf->sf_count[MCAST_INCLUDE])
301 return 0;
302 return pmc->sfcount[MCAST_EXCLUDE] ==
303 psf->sf_count[MCAST_EXCLUDE];
304 case IGMPV3_ALLOW_NEW_SOURCES:
305 if (gdeleted || !psf->sf_crcount)
306 return 0;
307 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
308 case IGMPV3_BLOCK_OLD_SOURCES:
309 if (pmc->sfmode == MCAST_INCLUDE)
310 return gdeleted || (psf->sf_crcount && sdeleted);
311 return psf->sf_crcount && !gdeleted && !sdeleted;
312 }
313 return 0;
314 }
315
316 static int
317 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
318 {
319 struct ip_sf_list *psf;
320 int scount = 0;
321
322 for (psf = pmc->sources; psf; psf = psf->sf_next) {
323 if (!is_in(pmc, psf, type, gdeleted, sdeleted))
324 continue;
325 scount++;
326 }
327 return scount;
328 }
329
330 /* source address selection per RFC 3376 section 4.2.13 */
331 static __be32 igmpv3_get_srcaddr(struct net_device *dev,
332 const struct flowi4 *fl4)
333 {
334 struct in_device *in_dev = __in_dev_get_rcu(dev);
335 const struct in_ifaddr *ifa;
336
337 if (!in_dev)
338 return htonl(INADDR_ANY);
339
340 in_dev_for_each_ifa_rcu(ifa, in_dev) {
341 if (fl4->saddr == ifa->ifa_local)
342 return fl4->saddr;
343 }
344
345 return htonl(INADDR_ANY);
346 }
347
348 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
349 {
350 struct sk_buff *skb;
351 struct rtable *rt;
352 struct iphdr *pip;
353 struct igmpv3_report *pig;
354 struct net *net = dev_net(dev);
355 struct flowi4 fl4;
356 int hlen = LL_RESERVED_SPACE(dev);
357 int tlen = dev->needed_tailroom;
358 unsigned int size;
359
360 size = min(mtu, IP_MAX_MTU);
361 while (1) {
362 skb = alloc_skb(size + hlen + tlen,
363 GFP_ATOMIC | __GFP_NOWARN);
364 if (skb)
365 break;
366 size >>= 1;
367 if (size < 256)
368 return NULL;
369 }
370 skb->priority = TC_PRIO_CONTROL;
371
372 rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
373 0, 0,
374 IPPROTO_IGMP, 0, dev->ifindex);
375 if (IS_ERR(rt)) {
376 kfree_skb(skb);
377 return NULL;
378 }
379
380 skb_dst_set(skb, &rt->dst);
381 skb->dev = dev;
382
383 skb_reserve(skb, hlen);
384 skb_tailroom_reserve(skb, mtu, tlen);
385
386 skb_reset_network_header(skb);
387 pip = ip_hdr(skb);
388 skb_put(skb, sizeof(struct iphdr) + 4);
389
390 pip->version = 4;
391 pip->ihl = (sizeof(struct iphdr)+4)>>2;
392 pip->tos = 0xc0;
393 pip->frag_off = htons(IP_DF);
394 pip->ttl = 1;
395 pip->daddr = fl4.daddr;
396
397 rcu_read_lock();
398 pip->saddr = igmpv3_get_srcaddr(dev, &fl4);
399 rcu_read_unlock();
400
401 pip->protocol = IPPROTO_IGMP;
402 pip->tot_len = 0; /* filled in later */
403 ip_select_ident(net, skb, NULL);
404 ((u8 *)&pip[1])[0] = IPOPT_RA;
405 ((u8 *)&pip[1])[1] = 4;
406 ((u8 *)&pip[1])[2] = 0;
407 ((u8 *)&pip[1])[3] = 0;
408
409 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
410 skb_put(skb, sizeof(*pig));
411 pig = igmpv3_report_hdr(skb);
412 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
413 pig->resv1 = 0;
414 pig->csum = 0;
415 pig->resv2 = 0;
416 pig->ngrec = 0;
417 return skb;
418 }
419
420 static int igmpv3_sendpack(struct sk_buff *skb)
421 {
422 struct igmphdr *pig = igmp_hdr(skb);
423 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
424
425 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
426
427 return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
428 }
429
430 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
431 {
432 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
433 }
434
435 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
436 int type, struct igmpv3_grec **ppgr, unsigned int mtu)
437 {
438 struct net_device *dev = pmc->interface->dev;
439 struct igmpv3_report *pih;
440 struct igmpv3_grec *pgr;
441
442 if (!skb) {
443 skb = igmpv3_newpack(dev, mtu);
444 if (!skb)
445 return NULL;
446 }
447 pgr = skb_put(skb, sizeof(struct igmpv3_grec));
448 pgr->grec_type = type;
449 pgr->grec_auxwords = 0;
450 pgr->grec_nsrcs = 0;
451 pgr->grec_mca = pmc->multiaddr;
452 pih = igmpv3_report_hdr(skb);
453 pih->ngrec = htons(ntohs(pih->ngrec)+1);
454 *ppgr = pgr;
455 return skb;
456 }
457
458 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0)
459
460 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
461 int type, int gdeleted, int sdeleted)
462 {
463 struct net_device *dev = pmc->interface->dev;
464 struct net *net = dev_net(dev);
465 struct igmpv3_report *pih;
466 struct igmpv3_grec *pgr = NULL;
467 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
468 int scount, stotal, first, isquery, truncate;
469 unsigned int mtu;
470
471 if (pmc->multiaddr == IGMP_ALL_HOSTS)
472 return skb;
473 if (ipv4_is_local_multicast(pmc->multiaddr) &&
474 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
475 return skb;
476
477 mtu = READ_ONCE(dev->mtu);
478 if (mtu < IPV4_MIN_MTU)
479 return skb;
480
481 isquery = type == IGMPV3_MODE_IS_INCLUDE ||
482 type == IGMPV3_MODE_IS_EXCLUDE;
483 truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
484 type == IGMPV3_CHANGE_TO_EXCLUDE;
485
486 stotal = scount = 0;
487
488 psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
489
490 if (!*psf_list)
491 goto empty_source;
492
493 pih = skb ? igmpv3_report_hdr(skb) : NULL;
494
495 /* EX and TO_EX get a fresh packet, if needed */
496 if (truncate) {
497 if (pih && pih->ngrec &&
498 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
499 if (skb)
500 igmpv3_sendpack(skb);
501 skb = igmpv3_newpack(dev, mtu);
502 }
503 }
504 first = 1;
505 psf_prev = NULL;
506 for (psf = *psf_list; psf; psf = psf_next) {
507 __be32 *psrc;
508
509 psf_next = psf->sf_next;
510
511 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
512 psf_prev = psf;
513 continue;
514 }
515
516 /* Based on RFC3376 5.1. Should not send source-list change
517 * records when there is a filter mode change.
518 */
519 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
520 (!gdeleted && pmc->crcount)) &&
521 (type == IGMPV3_ALLOW_NEW_SOURCES ||
522 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
523 goto decrease_sf_crcount;
524
525 /* clear marks on query responses */
526 if (isquery)
527 psf->sf_gsresp = 0;
528
529 if (AVAILABLE(skb) < sizeof(__be32) +
530 first*sizeof(struct igmpv3_grec)) {
531 if (truncate && !first)
532 break; /* truncate these */
533 if (pgr)
534 pgr->grec_nsrcs = htons(scount);
535 if (skb)
536 igmpv3_sendpack(skb);
537 skb = igmpv3_newpack(dev, mtu);
538 first = 1;
539 scount = 0;
540 }
541 if (first) {
542 skb = add_grhead(skb, pmc, type, &pgr, mtu);
543 first = 0;
544 }
545 if (!skb)
546 return NULL;
547 psrc = skb_put(skb, sizeof(__be32));
548 *psrc = psf->sf_inaddr;
549 scount++; stotal++;
550 if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
551 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
552 decrease_sf_crcount:
553 psf->sf_crcount--;
554 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
555 if (psf_prev)
556 psf_prev->sf_next = psf->sf_next;
557 else
558 *psf_list = psf->sf_next;
559 kfree(psf);
560 continue;
561 }
562 }
563 psf_prev = psf;
564 }
565
566 empty_source:
567 if (!stotal) {
568 if (type == IGMPV3_ALLOW_NEW_SOURCES ||
569 type == IGMPV3_BLOCK_OLD_SOURCES)
570 return skb;
571 if (pmc->crcount || isquery) {
572 /* make sure we have room for group header */
573 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
574 igmpv3_sendpack(skb);
575 skb = NULL; /* add_grhead will get a new one */
576 }
577 skb = add_grhead(skb, pmc, type, &pgr, mtu);
578 }
579 }
580 if (pgr)
581 pgr->grec_nsrcs = htons(scount);
582
583 if (isquery)
584 pmc->gsquery = 0; /* clear query state on report */
585 return skb;
586 }
587
588 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
589 {
590 struct sk_buff *skb = NULL;
591 struct net *net = dev_net(in_dev->dev);
592 int type;
593
594 if (!pmc) {
595 rcu_read_lock();
596 for_each_pmc_rcu(in_dev, pmc) {
597 if (pmc->multiaddr == IGMP_ALL_HOSTS)
598 continue;
599 if (ipv4_is_local_multicast(pmc->multiaddr) &&
600 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
601 continue;
602 spin_lock_bh(&pmc->lock);
603 if (pmc->sfcount[MCAST_EXCLUDE])
604 type = IGMPV3_MODE_IS_EXCLUDE;
605 else
606 type = IGMPV3_MODE_IS_INCLUDE;
607 skb = add_grec(skb, pmc, type, 0, 0);
608 spin_unlock_bh(&pmc->lock);
609 }
610 rcu_read_unlock();
611 } else {
612 spin_lock_bh(&pmc->lock);
613 if (pmc->sfcount[MCAST_EXCLUDE])
614 type = IGMPV3_MODE_IS_EXCLUDE;
615 else
616 type = IGMPV3_MODE_IS_INCLUDE;
617 skb = add_grec(skb, pmc, type, 0, 0);
618 spin_unlock_bh(&pmc->lock);
619 }
620 if (!skb)
621 return 0;
622 return igmpv3_sendpack(skb);
623 }
624
625 /*
626 * remove zero-count source records from a source filter list
627 */
628 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
629 {
630 struct ip_sf_list *psf_prev, *psf_next, *psf;
631
632 psf_prev = NULL;
633 for (psf = *ppsf; psf; psf = psf_next) {
634 psf_next = psf->sf_next;
635 if (psf->sf_crcount == 0) {
636 if (psf_prev)
637 psf_prev->sf_next = psf->sf_next;
638 else
639 *ppsf = psf->sf_next;
640 kfree(psf);
641 } else
642 psf_prev = psf;
643 }
644 }
645
646 static void kfree_pmc(struct ip_mc_list *pmc)
647 {
648 ip_sf_list_clear_all(pmc->sources);
649 ip_sf_list_clear_all(pmc->tomb);
650 kfree(pmc);
651 }
652
653 static void igmpv3_send_cr(struct in_device *in_dev)
654 {
655 struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
656 struct sk_buff *skb = NULL;
657 int type, dtype;
658
659 rcu_read_lock();
660 spin_lock_bh(&in_dev->mc_tomb_lock);
661
662 /* deleted MCA's */
663 pmc_prev = NULL;
664 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
665 pmc_next = pmc->next;
666 if (pmc->sfmode == MCAST_INCLUDE) {
667 type = IGMPV3_BLOCK_OLD_SOURCES;
668 dtype = IGMPV3_BLOCK_OLD_SOURCES;
669 skb = add_grec(skb, pmc, type, 1, 0);
670 skb = add_grec(skb, pmc, dtype, 1, 1);
671 }
672 if (pmc->crcount) {
673 if (pmc->sfmode == MCAST_EXCLUDE) {
674 type = IGMPV3_CHANGE_TO_INCLUDE;
675 skb = add_grec(skb, pmc, type, 1, 0);
676 }
677 pmc->crcount--;
678 if (pmc->crcount == 0) {
679 igmpv3_clear_zeros(&pmc->tomb);
680 igmpv3_clear_zeros(&pmc->sources);
681 }
682 }
683 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
684 if (pmc_prev)
685 pmc_prev->next = pmc_next;
686 else
687 in_dev->mc_tomb = pmc_next;
688 in_dev_put(pmc->interface);
689 kfree_pmc(pmc);
690 } else
691 pmc_prev = pmc;
692 }
693 spin_unlock_bh(&in_dev->mc_tomb_lock);
694
695 /* change recs */
696 for_each_pmc_rcu(in_dev, pmc) {
697 spin_lock_bh(&pmc->lock);
698 if (pmc->sfcount[MCAST_EXCLUDE]) {
699 type = IGMPV3_BLOCK_OLD_SOURCES;
700 dtype = IGMPV3_ALLOW_NEW_SOURCES;
701 } else {
702 type = IGMPV3_ALLOW_NEW_SOURCES;
703 dtype = IGMPV3_BLOCK_OLD_SOURCES;
704 }
705 skb = add_grec(skb, pmc, type, 0, 0);
706 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */
707
708 /* filter mode changes */
709 if (pmc->crcount) {
710 if (pmc->sfmode == MCAST_EXCLUDE)
711 type = IGMPV3_CHANGE_TO_EXCLUDE;
712 else
713 type = IGMPV3_CHANGE_TO_INCLUDE;
714 skb = add_grec(skb, pmc, type, 0, 0);
715 pmc->crcount--;
716 }
717 spin_unlock_bh(&pmc->lock);
718 }
719 rcu_read_unlock();
720
721 if (!skb)
722 return;
723 (void) igmpv3_sendpack(skb);
724 }
725
726 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
727 int type)
728 {
729 struct sk_buff *skb;
730 struct iphdr *iph;
731 struct igmphdr *ih;
732 struct rtable *rt;
733 struct net_device *dev = in_dev->dev;
734 struct net *net = dev_net(dev);
735 __be32 group = pmc ? pmc->multiaddr : 0;
736 struct flowi4 fl4;
737 __be32 dst;
738 int hlen, tlen;
739
740 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
741 return igmpv3_send_report(in_dev, pmc);
742
743 if (ipv4_is_local_multicast(group) &&
744 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
745 return 0;
746
747 if (type == IGMP_HOST_LEAVE_MESSAGE)
748 dst = IGMP_ALL_ROUTER;
749 else
750 dst = group;
751
752 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
753 0, 0,
754 IPPROTO_IGMP, 0, dev->ifindex);
755 if (IS_ERR(rt))
756 return -1;
757
758 hlen = LL_RESERVED_SPACE(dev);
759 tlen = dev->needed_tailroom;
760 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
761 if (!skb) {
762 ip_rt_put(rt);
763 return -1;
764 }
765 skb->priority = TC_PRIO_CONTROL;
766
767 skb_dst_set(skb, &rt->dst);
768
769 skb_reserve(skb, hlen);
770
771 skb_reset_network_header(skb);
772 iph = ip_hdr(skb);
773 skb_put(skb, sizeof(struct iphdr) + 4);
774
775 iph->version = 4;
776 iph->ihl = (sizeof(struct iphdr)+4)>>2;
777 iph->tos = 0xc0;
778 iph->frag_off = htons(IP_DF);
779 iph->ttl = 1;
780 iph->daddr = dst;
781 iph->saddr = fl4.saddr;
782 iph->protocol = IPPROTO_IGMP;
783 ip_select_ident(net, skb, NULL);
784 ((u8 *)&iph[1])[0] = IPOPT_RA;
785 ((u8 *)&iph[1])[1] = 4;
786 ((u8 *)&iph[1])[2] = 0;
787 ((u8 *)&iph[1])[3] = 0;
788
789 ih = skb_put(skb, sizeof(struct igmphdr));
790 ih->type = type;
791 ih->code = 0;
792 ih->csum = 0;
793 ih->group = group;
794 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
795
796 return ip_local_out(net, skb->sk, skb);
797 }
798
799 static void igmp_gq_timer_expire(struct timer_list *t)
800 {
801 struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer);
802
803 in_dev->mr_gq_running = 0;
804 igmpv3_send_report(in_dev, NULL);
805 in_dev_put(in_dev);
806 }
807
808 static void igmp_ifc_timer_expire(struct timer_list *t)
809 {
810 struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
811 u32 mr_ifc_count;
812
813 igmpv3_send_cr(in_dev);
814 restart:
815 mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count);
816
817 if (mr_ifc_count) {
818 if (cmpxchg(&in_dev->mr_ifc_count,
819 mr_ifc_count,
820 mr_ifc_count - 1) != mr_ifc_count)
821 goto restart;
822 igmp_ifc_start_timer(in_dev,
823 unsolicited_report_interval(in_dev));
824 }
825 in_dev_put(in_dev);
826 }
827
828 static void igmp_ifc_event(struct in_device *in_dev)
829 {
830 struct net *net = dev_net(in_dev->dev);
831 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
832 return;
833 WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv));
834 igmp_ifc_start_timer(in_dev, 1);
835 }
836
837
838 static void igmp_timer_expire(struct timer_list *t)
839 {
840 struct ip_mc_list *im = from_timer(im, t, timer);
841 struct in_device *in_dev = im->interface;
842
843 spin_lock(&im->lock);
844 im->tm_running = 0;
845
846 if (im->unsolicit_count && --im->unsolicit_count)
847 igmp_start_timer(im, unsolicited_report_interval(in_dev));
848
849 im->reporter = 1;
850 spin_unlock(&im->lock);
851
852 if (IGMP_V1_SEEN(in_dev))
853 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
854 else if (IGMP_V2_SEEN(in_dev))
855 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
856 else
857 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
858
859 ip_ma_put(im);
860 }
861
862 /* mark EXCLUDE-mode sources */
863 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
864 {
865 struct ip_sf_list *psf;
866 int i, scount;
867
868 scount = 0;
869 for (psf = pmc->sources; psf; psf = psf->sf_next) {
870 if (scount == nsrcs)
871 break;
872 for (i = 0; i < nsrcs; i++) {
873 /* skip inactive filters */
874 if (psf->sf_count[MCAST_INCLUDE] ||
875 pmc->sfcount[MCAST_EXCLUDE] !=
876 psf->sf_count[MCAST_EXCLUDE])
877 break;
878 if (srcs[i] == psf->sf_inaddr) {
879 scount++;
880 break;
881 }
882 }
883 }
884 pmc->gsquery = 0;
885 if (scount == nsrcs) /* all sources excluded */
886 return 0;
887 return 1;
888 }
889
890 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
891 {
892 struct ip_sf_list *psf;
893 int i, scount;
894
895 if (pmc->sfmode == MCAST_EXCLUDE)
896 return igmp_xmarksources(pmc, nsrcs, srcs);
897
898 /* mark INCLUDE-mode sources */
899 scount = 0;
900 for (psf = pmc->sources; psf; psf = psf->sf_next) {
901 if (scount == nsrcs)
902 break;
903 for (i = 0; i < nsrcs; i++)
904 if (srcs[i] == psf->sf_inaddr) {
905 psf->sf_gsresp = 1;
906 scount++;
907 break;
908 }
909 }
910 if (!scount) {
911 pmc->gsquery = 0;
912 return 0;
913 }
914 pmc->gsquery = 1;
915 return 1;
916 }
917
918 /* return true if packet was dropped */
919 static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
920 {
921 struct ip_mc_list *im;
922 struct net *net = dev_net(in_dev->dev);
923
924 /* Timers are only set for non-local groups */
925
926 if (group == IGMP_ALL_HOSTS)
927 return false;
928 if (ipv4_is_local_multicast(group) &&
929 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
930 return false;
931
932 rcu_read_lock();
933 for_each_pmc_rcu(in_dev, im) {
934 if (im->multiaddr == group) {
935 igmp_stop_timer(im);
936 break;
937 }
938 }
939 rcu_read_unlock();
940 return false;
941 }
942
943 /* return true if packet was dropped */
944 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
945 int len)
946 {
947 struct igmphdr *ih = igmp_hdr(skb);
948 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
949 struct ip_mc_list *im;
950 __be32 group = ih->group;
951 int max_delay;
952 int mark = 0;
953 struct net *net = dev_net(in_dev->dev);
954
955
956 if (len == 8) {
957 if (ih->code == 0) {
958 /* Alas, old v1 router presents here. */
959
960 max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
961 in_dev->mr_v1_seen = jiffies +
962 (in_dev->mr_qrv * in_dev->mr_qi) +
963 in_dev->mr_qri;
964 group = 0;
965 } else {
966 /* v2 router present */
967 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
968 in_dev->mr_v2_seen = jiffies +
969 (in_dev->mr_qrv * in_dev->mr_qi) +
970 in_dev->mr_qri;
971 }
972 /* cancel the interface change timer */
973 WRITE_ONCE(in_dev->mr_ifc_count, 0);
974 if (del_timer(&in_dev->mr_ifc_timer))
975 __in_dev_put(in_dev);
976 /* clear deleted report items */
977 igmpv3_clear_delrec(in_dev);
978 } else if (len < 12) {
979 return true; /* ignore bogus packet; freed by caller */
980 } else if (IGMP_V1_SEEN(in_dev)) {
981 /* This is a v3 query with v1 queriers present */
982 max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
983 group = 0;
984 } else if (IGMP_V2_SEEN(in_dev)) {
985 /* this is a v3 query with v2 queriers present;
986 * Interpretation of the max_delay code is problematic here.
987 * A real v2 host would use ih_code directly, while v3 has a
988 * different encoding. We use the v3 encoding as more likely
989 * to be intended in a v3 query.
990 */
991 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
992 if (!max_delay)
993 max_delay = 1; /* can't mod w/ 0 */
994 } else { /* v3 */
995 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
996 return true;
997
998 ih3 = igmpv3_query_hdr(skb);
999 if (ih3->nsrcs) {
1000 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
1001 + ntohs(ih3->nsrcs)*sizeof(__be32)))
1002 return true;
1003 ih3 = igmpv3_query_hdr(skb);
1004 }
1005
1006 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
1007 if (!max_delay)
1008 max_delay = 1; /* can't mod w/ 0 */
1009 in_dev->mr_maxdelay = max_delay;
1010
1011 /* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently
1012 * received value was zero, use the default or statically
1013 * configured value.
1014 */
1015 in_dev->mr_qrv = ih3->qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1016 in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
1017
1018 /* RFC3376, 8.3. Query Response Interval:
1019 * The number of seconds represented by the [Query Response
1020 * Interval] must be less than the [Query Interval].
1021 */
1022 if (in_dev->mr_qri >= in_dev->mr_qi)
1023 in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ;
1024
1025 if (!group) { /* general query */
1026 if (ih3->nsrcs)
1027 return true; /* no sources allowed */
1028 igmp_gq_start_timer(in_dev);
1029 return false;
1030 }
1031 /* mark sources to include, if group & source-specific */
1032 mark = ih3->nsrcs != 0;
1033 }
1034
1035 /*
1036 * - Start the timers in all of our membership records
1037 * that the query applies to for the interface on
1038 * which the query arrived excl. those that belong
1039 * to a "local" group (224.0.0.X)
1040 * - For timers already running check if they need to
1041 * be reset.
1042 * - Use the igmp->igmp_code field as the maximum
1043 * delay possible
1044 */
1045 rcu_read_lock();
1046 for_each_pmc_rcu(in_dev, im) {
1047 int changed;
1048
1049 if (group && group != im->multiaddr)
1050 continue;
1051 if (im->multiaddr == IGMP_ALL_HOSTS)
1052 continue;
1053 if (ipv4_is_local_multicast(im->multiaddr) &&
1054 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1055 continue;
1056 spin_lock_bh(&im->lock);
1057 if (im->tm_running)
1058 im->gsquery = im->gsquery && mark;
1059 else
1060 im->gsquery = mark;
1061 changed = !im->gsquery ||
1062 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1063 spin_unlock_bh(&im->lock);
1064 if (changed)
1065 igmp_mod_timer(im, max_delay);
1066 }
1067 rcu_read_unlock();
1068 return false;
1069 }
1070
1071 /* called in rcu_read_lock() section */
1072 int igmp_rcv(struct sk_buff *skb)
1073 {
1074 /* This basically follows the spec line by line -- see RFC1112 */
1075 struct igmphdr *ih;
1076 struct net_device *dev = skb->dev;
1077 struct in_device *in_dev;
1078 int len = skb->len;
1079 bool dropped = true;
1080
1081 if (netif_is_l3_master(dev)) {
1082 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1083 if (!dev)
1084 goto drop;
1085 }
1086
1087 in_dev = __in_dev_get_rcu(dev);
1088 if (!in_dev)
1089 goto drop;
1090
1091 if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1092 goto drop;
1093
1094 if (skb_checksum_simple_validate(skb))
1095 goto drop;
1096
1097 ih = igmp_hdr(skb);
1098 switch (ih->type) {
1099 case IGMP_HOST_MEMBERSHIP_QUERY:
1100 dropped = igmp_heard_query(in_dev, skb, len);
1101 break;
1102 case IGMP_HOST_MEMBERSHIP_REPORT:
1103 case IGMPV2_HOST_MEMBERSHIP_REPORT:
1104 /* Is it our report looped back? */
1105 if (rt_is_output_route(skb_rtable(skb)))
1106 break;
1107 /* don't rely on MC router hearing unicast reports */
1108 if (skb->pkt_type == PACKET_MULTICAST ||
1109 skb->pkt_type == PACKET_BROADCAST)
1110 dropped = igmp_heard_report(in_dev, ih->group);
1111 break;
1112 case IGMP_PIM:
1113 #ifdef CONFIG_IP_PIMSM_V1
1114 return pim_rcv_v1(skb);
1115 #endif
1116 case IGMPV3_HOST_MEMBERSHIP_REPORT:
1117 case IGMP_DVMRP:
1118 case IGMP_TRACE:
1119 case IGMP_HOST_LEAVE_MESSAGE:
1120 case IGMP_MTRACE:
1121 case IGMP_MTRACE_RESP:
1122 break;
1123 default:
1124 break;
1125 }
1126
1127 drop:
1128 if (dropped)
1129 kfree_skb(skb);
1130 else
1131 consume_skb(skb);
1132 return 0;
1133 }
1134
1135 #endif
1136
1137
1138 /*
1139 * Add a filter to a device
1140 */
1141
1142 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1143 {
1144 char buf[MAX_ADDR_LEN];
1145 struct net_device *dev = in_dev->dev;
1146
1147 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1148 We will get multicast token leakage, when IFF_MULTICAST
1149 is changed. This check should be done in ndo_set_rx_mode
1150 routine. Something sort of:
1151 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1152 --ANK
1153 */
1154 if (arp_mc_map(addr, buf, dev, 0) == 0)
1155 dev_mc_add(dev, buf);
1156 }
1157
1158 /*
1159 * Remove a filter from a device
1160 */
1161
1162 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1163 {
1164 char buf[MAX_ADDR_LEN];
1165 struct net_device *dev = in_dev->dev;
1166
1167 if (arp_mc_map(addr, buf, dev, 0) == 0)
1168 dev_mc_del(dev, buf);
1169 }
1170
1171 #ifdef CONFIG_IP_MULTICAST
1172 /*
1173 * deleted ip_mc_list manipulation
1174 */
1175 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
1176 gfp_t gfp)
1177 {
1178 struct ip_mc_list *pmc;
1179 struct net *net = dev_net(in_dev->dev);
1180
1181 /* this is an "ip_mc_list" for convenience; only the fields below
1182 * are actually used. In particular, the refcnt and users are not
1183 * used for management of the delete list. Using the same structure
1184 * for deleted items allows change reports to use common code with
1185 * non-deleted or query-response MCA's.
1186 */
1187 pmc = kzalloc(sizeof(*pmc), gfp);
1188 if (!pmc)
1189 return;
1190 spin_lock_init(&pmc->lock);
1191 spin_lock_bh(&im->lock);
1192 pmc->interface = im->interface;
1193 in_dev_hold(in_dev);
1194 pmc->multiaddr = im->multiaddr;
1195 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1196 pmc->sfmode = im->sfmode;
1197 if (pmc->sfmode == MCAST_INCLUDE) {
1198 struct ip_sf_list *psf;
1199
1200 pmc->tomb = im->tomb;
1201 pmc->sources = im->sources;
1202 im->tomb = im->sources = NULL;
1203 for (psf = pmc->sources; psf; psf = psf->sf_next)
1204 psf->sf_crcount = pmc->crcount;
1205 }
1206 spin_unlock_bh(&im->lock);
1207
1208 spin_lock_bh(&in_dev->mc_tomb_lock);
1209 pmc->next = in_dev->mc_tomb;
1210 in_dev->mc_tomb = pmc;
1211 spin_unlock_bh(&in_dev->mc_tomb_lock);
1212 }
1213
1214 /*
1215 * restore ip_mc_list deleted records
1216 */
1217 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1218 {
1219 struct ip_mc_list *pmc, *pmc_prev;
1220 struct ip_sf_list *psf;
1221 struct net *net = dev_net(in_dev->dev);
1222 __be32 multiaddr = im->multiaddr;
1223
1224 spin_lock_bh(&in_dev->mc_tomb_lock);
1225 pmc_prev = NULL;
1226 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1227 if (pmc->multiaddr == multiaddr)
1228 break;
1229 pmc_prev = pmc;
1230 }
1231 if (pmc) {
1232 if (pmc_prev)
1233 pmc_prev->next = pmc->next;
1234 else
1235 in_dev->mc_tomb = pmc->next;
1236 }
1237 spin_unlock_bh(&in_dev->mc_tomb_lock);
1238
1239 spin_lock_bh(&im->lock);
1240 if (pmc) {
1241 im->interface = pmc->interface;
1242 if (im->sfmode == MCAST_INCLUDE) {
1243 swap(im->tomb, pmc->tomb);
1244 swap(im->sources, pmc->sources);
1245 for (psf = im->sources; psf; psf = psf->sf_next)
1246 psf->sf_crcount = in_dev->mr_qrv ?:
1247 READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1248 } else {
1249 im->crcount = in_dev->mr_qrv ?:
1250 READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1251 }
1252 in_dev_put(pmc->interface);
1253 kfree_pmc(pmc);
1254 }
1255 spin_unlock_bh(&im->lock);
1256 }
1257
1258 /*
1259 * flush ip_mc_list deleted records
1260 */
1261 static void igmpv3_clear_delrec(struct in_device *in_dev)
1262 {
1263 struct ip_mc_list *pmc, *nextpmc;
1264
1265 spin_lock_bh(&in_dev->mc_tomb_lock);
1266 pmc = in_dev->mc_tomb;
1267 in_dev->mc_tomb = NULL;
1268 spin_unlock_bh(&in_dev->mc_tomb_lock);
1269
1270 for (; pmc; pmc = nextpmc) {
1271 nextpmc = pmc->next;
1272 ip_mc_clear_src(pmc);
1273 in_dev_put(pmc->interface);
1274 kfree_pmc(pmc);
1275 }
1276 /* clear dead sources, too */
1277 rcu_read_lock();
1278 for_each_pmc_rcu(in_dev, pmc) {
1279 struct ip_sf_list *psf;
1280
1281 spin_lock_bh(&pmc->lock);
1282 psf = pmc->tomb;
1283 pmc->tomb = NULL;
1284 spin_unlock_bh(&pmc->lock);
1285 ip_sf_list_clear_all(psf);
1286 }
1287 rcu_read_unlock();
1288 }
1289 #endif
1290
1291 static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
1292 {
1293 struct in_device *in_dev = im->interface;
1294 #ifdef CONFIG_IP_MULTICAST
1295 struct net *net = dev_net(in_dev->dev);
1296 int reporter;
1297 #endif
1298
1299 if (im->loaded) {
1300 im->loaded = 0;
1301 ip_mc_filter_del(in_dev, im->multiaddr);
1302 }
1303
1304 #ifdef CONFIG_IP_MULTICAST
1305 if (im->multiaddr == IGMP_ALL_HOSTS)
1306 return;
1307 if (ipv4_is_local_multicast(im->multiaddr) &&
1308 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1309 return;
1310
1311 reporter = im->reporter;
1312 igmp_stop_timer(im);
1313
1314 if (!in_dev->dead) {
1315 if (IGMP_V1_SEEN(in_dev))
1316 return;
1317 if (IGMP_V2_SEEN(in_dev)) {
1318 if (reporter)
1319 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1320 return;
1321 }
1322 /* IGMPv3 */
1323 igmpv3_add_delrec(in_dev, im, gfp);
1324
1325 igmp_ifc_event(in_dev);
1326 }
1327 #endif
1328 }
1329
1330 static void igmp_group_dropped(struct ip_mc_list *im)
1331 {
1332 __igmp_group_dropped(im, GFP_KERNEL);
1333 }
1334
1335 static void igmp_group_added(struct ip_mc_list *im)
1336 {
1337 struct in_device *in_dev = im->interface;
1338 #ifdef CONFIG_IP_MULTICAST
1339 struct net *net = dev_net(in_dev->dev);
1340 #endif
1341
1342 if (im->loaded == 0) {
1343 im->loaded = 1;
1344 ip_mc_filter_add(in_dev, im->multiaddr);
1345 }
1346
1347 #ifdef CONFIG_IP_MULTICAST
1348 if (im->multiaddr == IGMP_ALL_HOSTS)
1349 return;
1350 if (ipv4_is_local_multicast(im->multiaddr) &&
1351 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1352 return;
1353
1354 if (in_dev->dead)
1355 return;
1356
1357 im->unsolicit_count = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1358 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1359 spin_lock_bh(&im->lock);
1360 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1361 spin_unlock_bh(&im->lock);
1362 return;
1363 }
1364 /* else, v3 */
1365
1366 /* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should
1367 * not send filter-mode change record as the mode should be from
1368 * IN() to IN(A).
1369 */
1370 if (im->sfmode == MCAST_EXCLUDE)
1371 im->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1372
1373 igmp_ifc_event(in_dev);
1374 #endif
1375 }
1376
1377
1378 /*
1379 * Multicast list managers
1380 */
1381
1382 static u32 ip_mc_hash(const struct ip_mc_list *im)
1383 {
1384 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1385 }
1386
1387 static void ip_mc_hash_add(struct in_device *in_dev,
1388 struct ip_mc_list *im)
1389 {
1390 struct ip_mc_list __rcu **mc_hash;
1391 u32 hash;
1392
1393 mc_hash = rtnl_dereference(in_dev->mc_hash);
1394 if (mc_hash) {
1395 hash = ip_mc_hash(im);
1396 im->next_hash = mc_hash[hash];
1397 rcu_assign_pointer(mc_hash[hash], im);
1398 return;
1399 }
1400
1401 /* do not use a hash table for small number of items */
1402 if (in_dev->mc_count < 4)
1403 return;
1404
1405 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1406 GFP_KERNEL);
1407 if (!mc_hash)
1408 return;
1409
1410 for_each_pmc_rtnl(in_dev, im) {
1411 hash = ip_mc_hash(im);
1412 im->next_hash = mc_hash[hash];
1413 RCU_INIT_POINTER(mc_hash[hash], im);
1414 }
1415
1416 rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1417 }
1418
1419 static void ip_mc_hash_remove(struct in_device *in_dev,
1420 struct ip_mc_list *im)
1421 {
1422 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1423 struct ip_mc_list *aux;
1424
1425 if (!mc_hash)
1426 return;
1427 mc_hash += ip_mc_hash(im);
1428 while ((aux = rtnl_dereference(*mc_hash)) != im)
1429 mc_hash = &aux->next_hash;
1430 *mc_hash = im->next_hash;
1431 }
1432
1433
1434 /*
1435 * A socket has joined a multicast group on device dev.
1436 */
1437 static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
1438 unsigned int mode, gfp_t gfp)
1439 {
1440 struct ip_mc_list *im;
1441
1442 ASSERT_RTNL();
1443
1444 for_each_pmc_rtnl(in_dev, im) {
1445 if (im->multiaddr == addr) {
1446 im->users++;
1447 ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0);
1448 goto out;
1449 }
1450 }
1451
1452 im = kzalloc(sizeof(*im), gfp);
1453 if (!im)
1454 goto out;
1455
1456 im->users = 1;
1457 im->interface = in_dev;
1458 in_dev_hold(in_dev);
1459 im->multiaddr = addr;
1460 /* initial mode is (EX, empty) */
1461 im->sfmode = mode;
1462 im->sfcount[mode] = 1;
1463 refcount_set(&im->refcnt, 1);
1464 spin_lock_init(&im->lock);
1465 #ifdef CONFIG_IP_MULTICAST
1466 timer_setup(&im->timer, igmp_timer_expire, 0);
1467 #endif
1468
1469 im->next_rcu = in_dev->mc_list;
1470 in_dev->mc_count++;
1471 rcu_assign_pointer(in_dev->mc_list, im);
1472
1473 ip_mc_hash_add(in_dev, im);
1474
1475 #ifdef CONFIG_IP_MULTICAST
1476 igmpv3_del_delrec(in_dev, im);
1477 #endif
1478 igmp_group_added(im);
1479 if (!in_dev->dead)
1480 ip_rt_multicast_event(in_dev);
1481 out:
1482 return;
1483 }
1484
1485 void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1486 {
1487 ____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp);
1488 }
1489 EXPORT_SYMBOL(__ip_mc_inc_group);
1490
1491 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1492 {
1493 __ip_mc_inc_group(in_dev, addr, GFP_KERNEL);
1494 }
1495 EXPORT_SYMBOL(ip_mc_inc_group);
1496
1497 static int ip_mc_check_iphdr(struct sk_buff *skb)
1498 {
1499 const struct iphdr *iph;
1500 unsigned int len;
1501 unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1502
1503 if (!pskb_may_pull(skb, offset))
1504 return -EINVAL;
1505
1506 iph = ip_hdr(skb);
1507
1508 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1509 return -EINVAL;
1510
1511 offset += ip_hdrlen(skb) - sizeof(*iph);
1512
1513 if (!pskb_may_pull(skb, offset))
1514 return -EINVAL;
1515
1516 iph = ip_hdr(skb);
1517
1518 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1519 return -EINVAL;
1520
1521 len = skb_network_offset(skb) + ntohs(iph->tot_len);
1522 if (skb->len < len || len < offset)
1523 return -EINVAL;
1524
1525 skb_set_transport_header(skb, offset);
1526
1527 return 0;
1528 }
1529
1530 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1531 {
1532 unsigned int len = skb_transport_offset(skb);
1533
1534 len += sizeof(struct igmpv3_report);
1535
1536 return ip_mc_may_pull(skb, len) ? 0 : -EINVAL;
1537 }
1538
1539 static int ip_mc_check_igmp_query(struct sk_buff *skb)
1540 {
1541 unsigned int transport_len = ip_transport_len(skb);
1542 unsigned int len;
1543
1544 /* IGMPv{1,2}? */
1545 if (transport_len != sizeof(struct igmphdr)) {
1546 /* or IGMPv3? */
1547 if (transport_len < sizeof(struct igmpv3_query))
1548 return -EINVAL;
1549
1550 len = skb_transport_offset(skb) + sizeof(struct igmpv3_query);
1551 if (!ip_mc_may_pull(skb, len))
1552 return -EINVAL;
1553 }
1554
1555 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1556 * all-systems destination addresses (224.0.0.1) for general queries
1557 */
1558 if (!igmp_hdr(skb)->group &&
1559 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1560 return -EINVAL;
1561
1562 return 0;
1563 }
1564
1565 static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1566 {
1567 switch (igmp_hdr(skb)->type) {
1568 case IGMP_HOST_LEAVE_MESSAGE:
1569 case IGMP_HOST_MEMBERSHIP_REPORT:
1570 case IGMPV2_HOST_MEMBERSHIP_REPORT:
1571 return 0;
1572 case IGMPV3_HOST_MEMBERSHIP_REPORT:
1573 return ip_mc_check_igmp_reportv3(skb);
1574 case IGMP_HOST_MEMBERSHIP_QUERY:
1575 return ip_mc_check_igmp_query(skb);
1576 default:
1577 return -ENOMSG;
1578 }
1579 }
1580
1581 static __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1582 {
1583 return skb_checksum_simple_validate(skb);
1584 }
1585
1586 static int ip_mc_check_igmp_csum(struct sk_buff *skb)
1587 {
1588 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1589 unsigned int transport_len = ip_transport_len(skb);
1590 struct sk_buff *skb_chk;
1591
1592 if (!ip_mc_may_pull(skb, len))
1593 return -EINVAL;
1594
1595 skb_chk = skb_checksum_trimmed(skb, transport_len,
1596 ip_mc_validate_checksum);
1597 if (!skb_chk)
1598 return -EINVAL;
1599
1600 if (skb_chk != skb)
1601 kfree_skb(skb_chk);
1602
1603 return 0;
1604 }
1605
1606 /**
1607 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1608 * @skb: the skb to validate
1609 *
1610 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1611 * skb transport header accordingly and returns zero.
1612 *
1613 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1614 * standard
1615 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1616 * -ENOMEM: A memory allocation failure happened.
1617 *
1618 * Caller needs to set the skb network header and free any returned skb if it
1619 * differs from the provided skb.
1620 */
1621 int ip_mc_check_igmp(struct sk_buff *skb)
1622 {
1623 int ret = ip_mc_check_iphdr(skb);
1624
1625 if (ret < 0)
1626 return ret;
1627
1628 if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1629 return -ENOMSG;
1630
1631 ret = ip_mc_check_igmp_csum(skb);
1632 if (ret < 0)
1633 return ret;
1634
1635 return ip_mc_check_igmp_msg(skb);
1636 }
1637 EXPORT_SYMBOL(ip_mc_check_igmp);
1638
1639 /*
1640 * Resend IGMP JOIN report; used by netdev notifier.
1641 */
1642 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1643 {
1644 #ifdef CONFIG_IP_MULTICAST
1645 struct ip_mc_list *im;
1646 int type;
1647 struct net *net = dev_net(in_dev->dev);
1648
1649 ASSERT_RTNL();
1650
1651 for_each_pmc_rtnl(in_dev, im) {
1652 if (im->multiaddr == IGMP_ALL_HOSTS)
1653 continue;
1654 if (ipv4_is_local_multicast(im->multiaddr) &&
1655 !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
1656 continue;
1657
1658 /* a failover is happening and switches
1659 * must be notified immediately
1660 */
1661 if (IGMP_V1_SEEN(in_dev))
1662 type = IGMP_HOST_MEMBERSHIP_REPORT;
1663 else if (IGMP_V2_SEEN(in_dev))
1664 type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1665 else
1666 type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1667 igmp_send_report(in_dev, im, type);
1668 }
1669 #endif
1670 }
1671
1672 /*
1673 * A socket has left a multicast group on device dev
1674 */
1675
1676 void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1677 {
1678 struct ip_mc_list *i;
1679 struct ip_mc_list __rcu **ip;
1680
1681 ASSERT_RTNL();
1682
1683 for (ip = &in_dev->mc_list;
1684 (i = rtnl_dereference(*ip)) != NULL;
1685 ip = &i->next_rcu) {
1686 if (i->multiaddr == addr) {
1687 if (--i->users == 0) {
1688 ip_mc_hash_remove(in_dev, i);
1689 *ip = i->next_rcu;
1690 in_dev->mc_count--;
1691 __igmp_group_dropped(i, gfp);
1692 ip_mc_clear_src(i);
1693
1694 if (!in_dev->dead)
1695 ip_rt_multicast_event(in_dev);
1696
1697 ip_ma_put(i);
1698 return;
1699 }
1700 break;
1701 }
1702 }
1703 }
1704 EXPORT_SYMBOL(__ip_mc_dec_group);
1705
1706 /* Device changing type */
1707
1708 void ip_mc_unmap(struct in_device *in_dev)
1709 {
1710 struct ip_mc_list *pmc;
1711
1712 ASSERT_RTNL();
1713
1714 for_each_pmc_rtnl(in_dev, pmc)
1715 igmp_group_dropped(pmc);
1716 }
1717
1718 void ip_mc_remap(struct in_device *in_dev)
1719 {
1720 struct ip_mc_list *pmc;
1721
1722 ASSERT_RTNL();
1723
1724 for_each_pmc_rtnl(in_dev, pmc) {
1725 #ifdef CONFIG_IP_MULTICAST
1726 igmpv3_del_delrec(in_dev, pmc);
1727 #endif
1728 igmp_group_added(pmc);
1729 }
1730 }
1731
1732 /* Device going down */
1733
1734 void ip_mc_down(struct in_device *in_dev)
1735 {
1736 struct ip_mc_list *pmc;
1737
1738 ASSERT_RTNL();
1739
1740 for_each_pmc_rtnl(in_dev, pmc)
1741 igmp_group_dropped(pmc);
1742
1743 #ifdef CONFIG_IP_MULTICAST
1744 WRITE_ONCE(in_dev->mr_ifc_count, 0);
1745 if (del_timer(&in_dev->mr_ifc_timer))
1746 __in_dev_put(in_dev);
1747 in_dev->mr_gq_running = 0;
1748 if (del_timer(&in_dev->mr_gq_timer))
1749 __in_dev_put(in_dev);
1750 #endif
1751
1752 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1753 }
1754
1755 #ifdef CONFIG_IP_MULTICAST
1756 static void ip_mc_reset(struct in_device *in_dev)
1757 {
1758 struct net *net = dev_net(in_dev->dev);
1759
1760 in_dev->mr_qi = IGMP_QUERY_INTERVAL;
1761 in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
1762 in_dev->mr_qrv = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1763 }
1764 #else
1765 static void ip_mc_reset(struct in_device *in_dev)
1766 {
1767 }
1768 #endif
1769
1770 void ip_mc_init_dev(struct in_device *in_dev)
1771 {
1772 ASSERT_RTNL();
1773
1774 #ifdef CONFIG_IP_MULTICAST
1775 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1776 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
1777 #endif
1778 ip_mc_reset(in_dev);
1779
1780 spin_lock_init(&in_dev->mc_tomb_lock);
1781 }
1782
1783 /* Device going up */
1784
1785 void ip_mc_up(struct in_device *in_dev)
1786 {
1787 struct ip_mc_list *pmc;
1788
1789 ASSERT_RTNL();
1790
1791 ip_mc_reset(in_dev);
1792 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1793
1794 for_each_pmc_rtnl(in_dev, pmc) {
1795 #ifdef CONFIG_IP_MULTICAST
1796 igmpv3_del_delrec(in_dev, pmc);
1797 #endif
1798 igmp_group_added(pmc);
1799 }
1800 }
1801
1802 /*
1803 * Device is about to be destroyed: clean up.
1804 */
1805
1806 void ip_mc_destroy_dev(struct in_device *in_dev)
1807 {
1808 struct ip_mc_list *i;
1809
1810 ASSERT_RTNL();
1811
1812 /* Deactivate timers */
1813 ip_mc_down(in_dev);
1814 #ifdef CONFIG_IP_MULTICAST
1815 igmpv3_clear_delrec(in_dev);
1816 #endif
1817
1818 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1819 in_dev->mc_list = i->next_rcu;
1820 in_dev->mc_count--;
1821 ip_mc_clear_src(i);
1822 ip_ma_put(i);
1823 }
1824 }
1825
1826 /* RTNL is locked */
1827 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1828 {
1829 struct net_device *dev = NULL;
1830 struct in_device *idev = NULL;
1831
1832 if (imr->imr_ifindex) {
1833 idev = inetdev_by_index(net, imr->imr_ifindex);
1834 return idev;
1835 }
1836 if (imr->imr_address.s_addr) {
1837 dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1838 if (!dev)
1839 return NULL;
1840 }
1841
1842 if (!dev) {
1843 struct rtable *rt = ip_route_output(net,
1844 imr->imr_multiaddr.s_addr,
1845 0, 0, 0,
1846 RT_SCOPE_UNIVERSE);
1847 if (!IS_ERR(rt)) {
1848 dev = rt->dst.dev;
1849 ip_rt_put(rt);
1850 }
1851 }
1852 if (dev) {
1853 imr->imr_ifindex = dev->ifindex;
1854 idev = __in_dev_get_rtnl(dev);
1855 }
1856 return idev;
1857 }
1858
1859 /*
1860 * Join a socket to a group
1861 */
1862
1863 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1864 __be32 *psfsrc)
1865 {
1866 struct ip_sf_list *psf, *psf_prev;
1867 int rv = 0;
1868
1869 psf_prev = NULL;
1870 for (psf = pmc->sources; psf; psf = psf->sf_next) {
1871 if (psf->sf_inaddr == *psfsrc)
1872 break;
1873 psf_prev = psf;
1874 }
1875 if (!psf || psf->sf_count[sfmode] == 0) {
1876 /* source filter not found, or count wrong => bug */
1877 return -ESRCH;
1878 }
1879 psf->sf_count[sfmode]--;
1880 if (psf->sf_count[sfmode] == 0) {
1881 ip_rt_multicast_event(pmc->interface);
1882 }
1883 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1884 #ifdef CONFIG_IP_MULTICAST
1885 struct in_device *in_dev = pmc->interface;
1886 struct net *net = dev_net(in_dev->dev);
1887 #endif
1888
1889 /* no more filters for this source */
1890 if (psf_prev)
1891 psf_prev->sf_next = psf->sf_next;
1892 else
1893 pmc->sources = psf->sf_next;
1894 #ifdef CONFIG_IP_MULTICAST
1895 if (psf->sf_oldin &&
1896 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1897 psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1898 psf->sf_next = pmc->tomb;
1899 pmc->tomb = psf;
1900 rv = 1;
1901 } else
1902 #endif
1903 kfree(psf);
1904 }
1905 return rv;
1906 }
1907
1908 #ifndef CONFIG_IP_MULTICAST
1909 #define igmp_ifc_event(x) do { } while (0)
1910 #endif
1911
1912 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1913 int sfcount, __be32 *psfsrc, int delta)
1914 {
1915 struct ip_mc_list *pmc;
1916 int changerec = 0;
1917 int i, err;
1918
1919 if (!in_dev)
1920 return -ENODEV;
1921 rcu_read_lock();
1922 for_each_pmc_rcu(in_dev, pmc) {
1923 if (*pmca == pmc->multiaddr)
1924 break;
1925 }
1926 if (!pmc) {
1927 /* MCA not found?? bug */
1928 rcu_read_unlock();
1929 return -ESRCH;
1930 }
1931 spin_lock_bh(&pmc->lock);
1932 rcu_read_unlock();
1933 #ifdef CONFIG_IP_MULTICAST
1934 sf_markstate(pmc);
1935 #endif
1936 if (!delta) {
1937 err = -EINVAL;
1938 if (!pmc->sfcount[sfmode])
1939 goto out_unlock;
1940 pmc->sfcount[sfmode]--;
1941 }
1942 err = 0;
1943 for (i = 0; i < sfcount; i++) {
1944 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1945
1946 changerec |= rv > 0;
1947 if (!err && rv < 0)
1948 err = rv;
1949 }
1950 if (pmc->sfmode == MCAST_EXCLUDE &&
1951 pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1952 pmc->sfcount[MCAST_INCLUDE]) {
1953 #ifdef CONFIG_IP_MULTICAST
1954 struct ip_sf_list *psf;
1955 struct net *net = dev_net(in_dev->dev);
1956 #endif
1957
1958 /* filter mode change */
1959 pmc->sfmode = MCAST_INCLUDE;
1960 #ifdef CONFIG_IP_MULTICAST
1961 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
1962 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
1963 for (psf = pmc->sources; psf; psf = psf->sf_next)
1964 psf->sf_crcount = 0;
1965 igmp_ifc_event(pmc->interface);
1966 } else if (sf_setstate(pmc) || changerec) {
1967 igmp_ifc_event(pmc->interface);
1968 #endif
1969 }
1970 out_unlock:
1971 spin_unlock_bh(&pmc->lock);
1972 return err;
1973 }
1974
1975 /*
1976 * Add multicast single-source filter to the interface list
1977 */
1978 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1979 __be32 *psfsrc)
1980 {
1981 struct ip_sf_list *psf, *psf_prev;
1982
1983 psf_prev = NULL;
1984 for (psf = pmc->sources; psf; psf = psf->sf_next) {
1985 if (psf->sf_inaddr == *psfsrc)
1986 break;
1987 psf_prev = psf;
1988 }
1989 if (!psf) {
1990 psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1991 if (!psf)
1992 return -ENOBUFS;
1993 psf->sf_inaddr = *psfsrc;
1994 if (psf_prev) {
1995 psf_prev->sf_next = psf;
1996 } else
1997 pmc->sources = psf;
1998 }
1999 psf->sf_count[sfmode]++;
2000 if (psf->sf_count[sfmode] == 1) {
2001 ip_rt_multicast_event(pmc->interface);
2002 }
2003 return 0;
2004 }
2005
2006 #ifdef CONFIG_IP_MULTICAST
2007 static void sf_markstate(struct ip_mc_list *pmc)
2008 {
2009 struct ip_sf_list *psf;
2010 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2011
2012 for (psf = pmc->sources; psf; psf = psf->sf_next)
2013 if (pmc->sfcount[MCAST_EXCLUDE]) {
2014 psf->sf_oldin = mca_xcount ==
2015 psf->sf_count[MCAST_EXCLUDE] &&
2016 !psf->sf_count[MCAST_INCLUDE];
2017 } else
2018 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2019 }
2020
2021 static int sf_setstate(struct ip_mc_list *pmc)
2022 {
2023 struct ip_sf_list *psf, *dpsf;
2024 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2025 int qrv = pmc->interface->mr_qrv;
2026 int new_in, rv;
2027
2028 rv = 0;
2029 for (psf = pmc->sources; psf; psf = psf->sf_next) {
2030 if (pmc->sfcount[MCAST_EXCLUDE]) {
2031 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2032 !psf->sf_count[MCAST_INCLUDE];
2033 } else
2034 new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2035 if (new_in) {
2036 if (!psf->sf_oldin) {
2037 struct ip_sf_list *prev = NULL;
2038
2039 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
2040 if (dpsf->sf_inaddr == psf->sf_inaddr)
2041 break;
2042 prev = dpsf;
2043 }
2044 if (dpsf) {
2045 if (prev)
2046 prev->sf_next = dpsf->sf_next;
2047 else
2048 pmc->tomb = dpsf->sf_next;
2049 kfree(dpsf);
2050 }
2051 psf->sf_crcount = qrv;
2052 rv++;
2053 }
2054 } else if (psf->sf_oldin) {
2055
2056 psf->sf_crcount = 0;
2057 /*
2058 * add or update "delete" records if an active filter
2059 * is now inactive
2060 */
2061 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2062 if (dpsf->sf_inaddr == psf->sf_inaddr)
2063 break;
2064 if (!dpsf) {
2065 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2066 if (!dpsf)
2067 continue;
2068 *dpsf = *psf;
2069 /* pmc->lock held by callers */
2070 dpsf->sf_next = pmc->tomb;
2071 pmc->tomb = dpsf;
2072 }
2073 dpsf->sf_crcount = qrv;
2074 rv++;
2075 }
2076 }
2077 return rv;
2078 }
2079 #endif
2080
2081 /*
2082 * Add multicast source filter list to the interface list
2083 */
2084 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2085 int sfcount, __be32 *psfsrc, int delta)
2086 {
2087 struct ip_mc_list *pmc;
2088 int isexclude;
2089 int i, err;
2090
2091 if (!in_dev)
2092 return -ENODEV;
2093 rcu_read_lock();
2094 for_each_pmc_rcu(in_dev, pmc) {
2095 if (*pmca == pmc->multiaddr)
2096 break;
2097 }
2098 if (!pmc) {
2099 /* MCA not found?? bug */
2100 rcu_read_unlock();
2101 return -ESRCH;
2102 }
2103 spin_lock_bh(&pmc->lock);
2104 rcu_read_unlock();
2105
2106 #ifdef CONFIG_IP_MULTICAST
2107 sf_markstate(pmc);
2108 #endif
2109 isexclude = pmc->sfmode == MCAST_EXCLUDE;
2110 if (!delta)
2111 pmc->sfcount[sfmode]++;
2112 err = 0;
2113 for (i = 0; i < sfcount; i++) {
2114 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2115 if (err)
2116 break;
2117 }
2118 if (err) {
2119 int j;
2120
2121 if (!delta)
2122 pmc->sfcount[sfmode]--;
2123 for (j = 0; j < i; j++)
2124 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2125 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2126 #ifdef CONFIG_IP_MULTICAST
2127 struct ip_sf_list *psf;
2128 struct net *net = dev_net(pmc->interface->dev);
2129 in_dev = pmc->interface;
2130 #endif
2131
2132 /* filter mode change */
2133 if (pmc->sfcount[MCAST_EXCLUDE])
2134 pmc->sfmode = MCAST_EXCLUDE;
2135 else if (pmc->sfcount[MCAST_INCLUDE])
2136 pmc->sfmode = MCAST_INCLUDE;
2137 #ifdef CONFIG_IP_MULTICAST
2138 /* else no filters; keep old mode for reports */
2139
2140 pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
2141 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
2142 for (psf = pmc->sources; psf; psf = psf->sf_next)
2143 psf->sf_crcount = 0;
2144 igmp_ifc_event(in_dev);
2145 } else if (sf_setstate(pmc)) {
2146 igmp_ifc_event(in_dev);
2147 #endif
2148 }
2149 spin_unlock_bh(&pmc->lock);
2150 return err;
2151 }
2152
2153 static void ip_mc_clear_src(struct ip_mc_list *pmc)
2154 {
2155 struct ip_sf_list *tomb, *sources;
2156
2157 spin_lock_bh(&pmc->lock);
2158 tomb = pmc->tomb;
2159 pmc->tomb = NULL;
2160 sources = pmc->sources;
2161 pmc->sources = NULL;
2162 pmc->sfmode = MCAST_EXCLUDE;
2163 pmc->sfcount[MCAST_INCLUDE] = 0;
2164 pmc->sfcount[MCAST_EXCLUDE] = 1;
2165 spin_unlock_bh(&pmc->lock);
2166
2167 ip_sf_list_clear_all(tomb);
2168 ip_sf_list_clear_all(sources);
2169 }
2170
2171 /* Join a multicast group
2172 */
2173 static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
2174 unsigned int mode)
2175 {
2176 __be32 addr = imr->imr_multiaddr.s_addr;
2177 struct ip_mc_socklist *iml, *i;
2178 struct in_device *in_dev;
2179 struct inet_sock *inet = inet_sk(sk);
2180 struct net *net = sock_net(sk);
2181 int ifindex;
2182 int count = 0;
2183 int err;
2184
2185 ASSERT_RTNL();
2186
2187 if (!ipv4_is_multicast(addr))
2188 return -EINVAL;
2189
2190 in_dev = ip_mc_find_dev(net, imr);
2191
2192 if (!in_dev) {
2193 err = -ENODEV;
2194 goto done;
2195 }
2196
2197 err = -EADDRINUSE;
2198 ifindex = imr->imr_ifindex;
2199 for_each_pmc_rtnl(inet, i) {
2200 if (i->multi.imr_multiaddr.s_addr == addr &&
2201 i->multi.imr_ifindex == ifindex)
2202 goto done;
2203 count++;
2204 }
2205 err = -ENOBUFS;
2206 if (count >= READ_ONCE(net->ipv4.sysctl_igmp_max_memberships))
2207 goto done;
2208 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2209 if (!iml)
2210 goto done;
2211
2212 memcpy(&iml->multi, imr, sizeof(*imr));
2213 iml->next_rcu = inet->mc_list;
2214 iml->sflist = NULL;
2215 iml->sfmode = mode;
2216 rcu_assign_pointer(inet->mc_list, iml);
2217 ____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL);
2218 err = 0;
2219 done:
2220 return err;
2221 }
2222
2223 /* Join ASM (Any-Source Multicast) group
2224 */
2225 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2226 {
2227 return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE);
2228 }
2229 EXPORT_SYMBOL(ip_mc_join_group);
2230
2231 /* Join SSM (Source-Specific Multicast) group
2232 */
2233 int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
2234 unsigned int mode)
2235 {
2236 return __ip_mc_join_group(sk, imr, mode);
2237 }
2238
2239 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2240 struct in_device *in_dev)
2241 {
2242 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2243 int err;
2244
2245 if (!psf) {
2246 /* any-source empty exclude case */
2247 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2248 iml->sfmode, 0, NULL, 0);
2249 }
2250 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2251 iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2252 RCU_INIT_POINTER(iml->sflist, NULL);
2253 /* decrease mem now to avoid the memleak warning */
2254 atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc);
2255 kfree_rcu(psf, rcu);
2256 return err;
2257 }
2258
2259 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2260 {
2261 struct inet_sock *inet = inet_sk(sk);
2262 struct ip_mc_socklist *iml;
2263 struct ip_mc_socklist __rcu **imlp;
2264 struct in_device *in_dev;
2265 struct net *net = sock_net(sk);
2266 __be32 group = imr->imr_multiaddr.s_addr;
2267 u32 ifindex;
2268 int ret = -EADDRNOTAVAIL;
2269
2270 ASSERT_RTNL();
2271
2272 in_dev = ip_mc_find_dev(net, imr);
2273 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2274 ret = -ENODEV;
2275 goto out;
2276 }
2277 ifindex = imr->imr_ifindex;
2278 for (imlp = &inet->mc_list;
2279 (iml = rtnl_dereference(*imlp)) != NULL;
2280 imlp = &iml->next_rcu) {
2281 if (iml->multi.imr_multiaddr.s_addr != group)
2282 continue;
2283 if (ifindex) {
2284 if (iml->multi.imr_ifindex != ifindex)
2285 continue;
2286 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2287 iml->multi.imr_address.s_addr)
2288 continue;
2289
2290 (void) ip_mc_leave_src(sk, iml, in_dev);
2291
2292 *imlp = iml->next_rcu;
2293
2294 if (in_dev)
2295 ip_mc_dec_group(in_dev, group);
2296
2297 /* decrease mem now to avoid the memleak warning */
2298 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2299 kfree_rcu(iml, rcu);
2300 return 0;
2301 }
2302 out:
2303 return ret;
2304 }
2305 EXPORT_SYMBOL(ip_mc_leave_group);
2306
2307 int ip_mc_source(int add, int omode, struct sock *sk, struct
2308 ip_mreq_source *mreqs, int ifindex)
2309 {
2310 int err;
2311 struct ip_mreqn imr;
2312 __be32 addr = mreqs->imr_multiaddr;
2313 struct ip_mc_socklist *pmc;
2314 struct in_device *in_dev = NULL;
2315 struct inet_sock *inet = inet_sk(sk);
2316 struct ip_sf_socklist *psl;
2317 struct net *net = sock_net(sk);
2318 int leavegroup = 0;
2319 int i, j, rv;
2320
2321 if (!ipv4_is_multicast(addr))
2322 return -EINVAL;
2323
2324 ASSERT_RTNL();
2325
2326 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2327 imr.imr_address.s_addr = mreqs->imr_interface;
2328 imr.imr_ifindex = ifindex;
2329 in_dev = ip_mc_find_dev(net, &imr);
2330
2331 if (!in_dev) {
2332 err = -ENODEV;
2333 goto done;
2334 }
2335 err = -EADDRNOTAVAIL;
2336
2337 for_each_pmc_rtnl(inet, pmc) {
2338 if ((pmc->multi.imr_multiaddr.s_addr ==
2339 imr.imr_multiaddr.s_addr) &&
2340 (pmc->multi.imr_ifindex == imr.imr_ifindex))
2341 break;
2342 }
2343 if (!pmc) { /* must have a prior join */
2344 err = -EINVAL;
2345 goto done;
2346 }
2347 /* if a source filter was set, must be the same mode as before */
2348 if (pmc->sflist) {
2349 if (pmc->sfmode != omode) {
2350 err = -EINVAL;
2351 goto done;
2352 }
2353 } else if (pmc->sfmode != omode) {
2354 /* allow mode switches for empty-set filters */
2355 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2356 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2357 NULL, 0);
2358 pmc->sfmode = omode;
2359 }
2360
2361 psl = rtnl_dereference(pmc->sflist);
2362 if (!add) {
2363 if (!psl)
2364 goto done; /* err = -EADDRNOTAVAIL */
2365 rv = !0;
2366 for (i = 0; i < psl->sl_count; i++) {
2367 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2368 sizeof(__be32));
2369 if (rv == 0)
2370 break;
2371 }
2372 if (rv) /* source not found */
2373 goto done; /* err = -EADDRNOTAVAIL */
2374
2375 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2376 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2377 leavegroup = 1;
2378 goto done;
2379 }
2380
2381 /* update the interface filter */
2382 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2383 &mreqs->imr_sourceaddr, 1);
2384
2385 for (j = i+1; j < psl->sl_count; j++)
2386 psl->sl_addr[j-1] = psl->sl_addr[j];
2387 psl->sl_count--;
2388 err = 0;
2389 goto done;
2390 }
2391 /* else, add a new source to the filter */
2392
2393 if (psl && psl->sl_count >= READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) {
2394 err = -ENOBUFS;
2395 goto done;
2396 }
2397 if (!psl || psl->sl_count == psl->sl_max) {
2398 struct ip_sf_socklist *newpsl;
2399 int count = IP_SFBLOCK;
2400
2401 if (psl)
2402 count += psl->sl_max;
2403 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count),
2404 GFP_KERNEL);
2405 if (!newpsl) {
2406 err = -ENOBUFS;
2407 goto done;
2408 }
2409 newpsl->sl_max = count;
2410 newpsl->sl_count = count - IP_SFBLOCK;
2411 if (psl) {
2412 for (i = 0; i < psl->sl_count; i++)
2413 newpsl->sl_addr[i] = psl->sl_addr[i];
2414 /* decrease mem now to avoid the memleak warning */
2415 atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2416 &sk->sk_omem_alloc);
2417 }
2418 rcu_assign_pointer(pmc->sflist, newpsl);
2419 if (psl)
2420 kfree_rcu(psl, rcu);
2421 psl = newpsl;
2422 }
2423 rv = 1; /* > 0 for insert logic below if sl_count is 0 */
2424 for (i = 0; i < psl->sl_count; i++) {
2425 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2426 sizeof(__be32));
2427 if (rv == 0)
2428 break;
2429 }
2430 if (rv == 0) /* address already there is an error */
2431 goto done;
2432 for (j = psl->sl_count-1; j >= i; j--)
2433 psl->sl_addr[j+1] = psl->sl_addr[j];
2434 psl->sl_addr[i] = mreqs->imr_sourceaddr;
2435 psl->sl_count++;
2436 err = 0;
2437 /* update the interface list */
2438 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2439 &mreqs->imr_sourceaddr, 1);
2440 done:
2441 if (leavegroup)
2442 err = ip_mc_leave_group(sk, &imr);
2443 return err;
2444 }
2445
2446 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2447 {
2448 int err = 0;
2449 struct ip_mreqn imr;
2450 __be32 addr = msf->imsf_multiaddr;
2451 struct ip_mc_socklist *pmc;
2452 struct in_device *in_dev;
2453 struct inet_sock *inet = inet_sk(sk);
2454 struct ip_sf_socklist *newpsl, *psl;
2455 struct net *net = sock_net(sk);
2456 int leavegroup = 0;
2457
2458 if (!ipv4_is_multicast(addr))
2459 return -EINVAL;
2460 if (msf->imsf_fmode != MCAST_INCLUDE &&
2461 msf->imsf_fmode != MCAST_EXCLUDE)
2462 return -EINVAL;
2463
2464 ASSERT_RTNL();
2465
2466 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2467 imr.imr_address.s_addr = msf->imsf_interface;
2468 imr.imr_ifindex = ifindex;
2469 in_dev = ip_mc_find_dev(net, &imr);
2470
2471 if (!in_dev) {
2472 err = -ENODEV;
2473 goto done;
2474 }
2475
2476 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2477 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2478 leavegroup = 1;
2479 goto done;
2480 }
2481
2482 for_each_pmc_rtnl(inet, pmc) {
2483 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2484 pmc->multi.imr_ifindex == imr.imr_ifindex)
2485 break;
2486 }
2487 if (!pmc) { /* must have a prior join */
2488 err = -EINVAL;
2489 goto done;
2490 }
2491 if (msf->imsf_numsrc) {
2492 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr,
2493 msf->imsf_numsrc),
2494 GFP_KERNEL);
2495 if (!newpsl) {
2496 err = -ENOBUFS;
2497 goto done;
2498 }
2499 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2500 memcpy(newpsl->sl_addr, msf->imsf_slist_flex,
2501 flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc));
2502 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2503 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2504 if (err) {
2505 sock_kfree_s(sk, newpsl,
2506 struct_size(newpsl, sl_addr,
2507 newpsl->sl_max));
2508 goto done;
2509 }
2510 } else {
2511 newpsl = NULL;
2512 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2513 msf->imsf_fmode, 0, NULL, 0);
2514 }
2515 psl = rtnl_dereference(pmc->sflist);
2516 if (psl) {
2517 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2518 psl->sl_count, psl->sl_addr, 0);
2519 /* decrease mem now to avoid the memleak warning */
2520 atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2521 &sk->sk_omem_alloc);
2522 } else {
2523 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2524 0, NULL, 0);
2525 }
2526 rcu_assign_pointer(pmc->sflist, newpsl);
2527 if (psl)
2528 kfree_rcu(psl, rcu);
2529 pmc->sfmode = msf->imsf_fmode;
2530 err = 0;
2531 done:
2532 if (leavegroup)
2533 err = ip_mc_leave_group(sk, &imr);
2534 return err;
2535 }
2536 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2537 sockptr_t optval, sockptr_t optlen)
2538 {
2539 int err, len, count, copycount, msf_size;
2540 struct ip_mreqn imr;
2541 __be32 addr = msf->imsf_multiaddr;
2542 struct ip_mc_socklist *pmc;
2543 struct in_device *in_dev;
2544 struct inet_sock *inet = inet_sk(sk);
2545 struct ip_sf_socklist *psl;
2546 struct net *net = sock_net(sk);
2547
2548 ASSERT_RTNL();
2549
2550 if (!ipv4_is_multicast(addr))
2551 return -EINVAL;
2552
2553 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2554 imr.imr_address.s_addr = msf->imsf_interface;
2555 imr.imr_ifindex = 0;
2556 in_dev = ip_mc_find_dev(net, &imr);
2557
2558 if (!in_dev) {
2559 err = -ENODEV;
2560 goto done;
2561 }
2562 err = -EADDRNOTAVAIL;
2563
2564 for_each_pmc_rtnl(inet, pmc) {
2565 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2566 pmc->multi.imr_ifindex == imr.imr_ifindex)
2567 break;
2568 }
2569 if (!pmc) /* must have a prior join */
2570 goto done;
2571 msf->imsf_fmode = pmc->sfmode;
2572 psl = rtnl_dereference(pmc->sflist);
2573 if (!psl) {
2574 count = 0;
2575 } else {
2576 count = psl->sl_count;
2577 }
2578 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2579 len = flex_array_size(psl, sl_addr, copycount);
2580 msf->imsf_numsrc = count;
2581 msf_size = IP_MSFILTER_SIZE(copycount);
2582 if (copy_to_sockptr(optlen, &msf_size, sizeof(int)) ||
2583 copy_to_sockptr(optval, msf, IP_MSFILTER_SIZE(0))) {
2584 return -EFAULT;
2585 }
2586 if (len &&
2587 copy_to_sockptr_offset(optval,
2588 offsetof(struct ip_msfilter, imsf_slist_flex),
2589 psl->sl_addr, len))
2590 return -EFAULT;
2591 return 0;
2592 done:
2593 return err;
2594 }
2595
2596 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2597 sockptr_t optval, size_t ss_offset)
2598 {
2599 int i, count, copycount;
2600 struct sockaddr_in *psin;
2601 __be32 addr;
2602 struct ip_mc_socklist *pmc;
2603 struct inet_sock *inet = inet_sk(sk);
2604 struct ip_sf_socklist *psl;
2605
2606 ASSERT_RTNL();
2607
2608 psin = (struct sockaddr_in *)&gsf->gf_group;
2609 if (psin->sin_family != AF_INET)
2610 return -EINVAL;
2611 addr = psin->sin_addr.s_addr;
2612 if (!ipv4_is_multicast(addr))
2613 return -EINVAL;
2614
2615 for_each_pmc_rtnl(inet, pmc) {
2616 if (pmc->multi.imr_multiaddr.s_addr == addr &&
2617 pmc->multi.imr_ifindex == gsf->gf_interface)
2618 break;
2619 }
2620 if (!pmc) /* must have a prior join */
2621 return -EADDRNOTAVAIL;
2622 gsf->gf_fmode = pmc->sfmode;
2623 psl = rtnl_dereference(pmc->sflist);
2624 count = psl ? psl->sl_count : 0;
2625 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2626 gsf->gf_numsrc = count;
2627 for (i = 0; i < copycount; i++) {
2628 struct sockaddr_storage ss;
2629
2630 psin = (struct sockaddr_in *)&ss;
2631 memset(&ss, 0, sizeof(ss));
2632 psin->sin_family = AF_INET;
2633 psin->sin_addr.s_addr = psl->sl_addr[i];
2634 if (copy_to_sockptr_offset(optval, ss_offset,
2635 &ss, sizeof(ss)))
2636 return -EFAULT;
2637 ss_offset += sizeof(ss);
2638 }
2639 return 0;
2640 }
2641
2642 /*
2643 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2644 */
2645 int ip_mc_sf_allow(const struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2646 int dif, int sdif)
2647 {
2648 const struct inet_sock *inet = inet_sk(sk);
2649 struct ip_mc_socklist *pmc;
2650 struct ip_sf_socklist *psl;
2651 int i;
2652 int ret;
2653
2654 ret = 1;
2655 if (!ipv4_is_multicast(loc_addr))
2656 goto out;
2657
2658 rcu_read_lock();
2659 for_each_pmc_rcu(inet, pmc) {
2660 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2661 (pmc->multi.imr_ifindex == dif ||
2662 (sdif && pmc->multi.imr_ifindex == sdif)))
2663 break;
2664 }
2665 ret = inet_test_bit(MC_ALL, sk);
2666 if (!pmc)
2667 goto unlock;
2668 psl = rcu_dereference(pmc->sflist);
2669 ret = (pmc->sfmode == MCAST_EXCLUDE);
2670 if (!psl)
2671 goto unlock;
2672
2673 for (i = 0; i < psl->sl_count; i++) {
2674 if (psl->sl_addr[i] == rmt_addr)
2675 break;
2676 }
2677 ret = 0;
2678 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2679 goto unlock;
2680 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2681 goto unlock;
2682 ret = 1;
2683 unlock:
2684 rcu_read_unlock();
2685 out:
2686 return ret;
2687 }
2688
2689 /*
2690 * A socket is closing.
2691 */
2692
2693 void ip_mc_drop_socket(struct sock *sk)
2694 {
2695 struct inet_sock *inet = inet_sk(sk);
2696 struct ip_mc_socklist *iml;
2697 struct net *net = sock_net(sk);
2698
2699 if (!inet->mc_list)
2700 return;
2701
2702 rtnl_lock();
2703 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2704 struct in_device *in_dev;
2705
2706 inet->mc_list = iml->next_rcu;
2707 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2708 (void) ip_mc_leave_src(sk, iml, in_dev);
2709 if (in_dev)
2710 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2711 /* decrease mem now to avoid the memleak warning */
2712 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2713 kfree_rcu(iml, rcu);
2714 }
2715 rtnl_unlock();
2716 }
2717
2718 /* called with rcu_read_lock() */
2719 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2720 {
2721 struct ip_mc_list *im;
2722 struct ip_mc_list __rcu **mc_hash;
2723 struct ip_sf_list *psf;
2724 int rv = 0;
2725
2726 mc_hash = rcu_dereference(in_dev->mc_hash);
2727 if (mc_hash) {
2728 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2729
2730 for (im = rcu_dereference(mc_hash[hash]);
2731 im != NULL;
2732 im = rcu_dereference(im->next_hash)) {
2733 if (im->multiaddr == mc_addr)
2734 break;
2735 }
2736 } else {
2737 for_each_pmc_rcu(in_dev, im) {
2738 if (im->multiaddr == mc_addr)
2739 break;
2740 }
2741 }
2742 if (im && proto == IPPROTO_IGMP) {
2743 rv = 1;
2744 } else if (im) {
2745 if (src_addr) {
2746 spin_lock_bh(&im->lock);
2747 for (psf = im->sources; psf; psf = psf->sf_next) {
2748 if (psf->sf_inaddr == src_addr)
2749 break;
2750 }
2751 if (psf)
2752 rv = psf->sf_count[MCAST_INCLUDE] ||
2753 psf->sf_count[MCAST_EXCLUDE] !=
2754 im->sfcount[MCAST_EXCLUDE];
2755 else
2756 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2757 spin_unlock_bh(&im->lock);
2758 } else
2759 rv = 1; /* unspecified source; tentatively allow */
2760 }
2761 return rv;
2762 }
2763
2764 #if defined(CONFIG_PROC_FS)
2765 struct igmp_mc_iter_state {
2766 struct seq_net_private p;
2767 struct net_device *dev;
2768 struct in_device *in_dev;
2769 };
2770
2771 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private)
2772
2773 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2774 {
2775 struct net *net = seq_file_net(seq);
2776 struct ip_mc_list *im = NULL;
2777 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2778
2779 state->in_dev = NULL;
2780 for_each_netdev_rcu(net, state->dev) {
2781 struct in_device *in_dev;
2782
2783 in_dev = __in_dev_get_rcu(state->dev);
2784 if (!in_dev)
2785 continue;
2786 im = rcu_dereference(in_dev->mc_list);
2787 if (im) {
2788 state->in_dev = in_dev;
2789 break;
2790 }
2791 }
2792 return im;
2793 }
2794
2795 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2796 {
2797 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2798
2799 im = rcu_dereference(im->next_rcu);
2800 while (!im) {
2801 state->dev = next_net_device_rcu(state->dev);
2802 if (!state->dev) {
2803 state->in_dev = NULL;
2804 break;
2805 }
2806 state->in_dev = __in_dev_get_rcu(state->dev);
2807 if (!state->in_dev)
2808 continue;
2809 im = rcu_dereference(state->in_dev->mc_list);
2810 }
2811 return im;
2812 }
2813
2814 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2815 {
2816 struct ip_mc_list *im = igmp_mc_get_first(seq);
2817 if (im)
2818 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2819 --pos;
2820 return pos ? NULL : im;
2821 }
2822
2823 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2824 __acquires(rcu)
2825 {
2826 rcu_read_lock();
2827 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2828 }
2829
2830 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2831 {
2832 struct ip_mc_list *im;
2833 if (v == SEQ_START_TOKEN)
2834 im = igmp_mc_get_first(seq);
2835 else
2836 im = igmp_mc_get_next(seq, v);
2837 ++*pos;
2838 return im;
2839 }
2840
2841 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2842 __releases(rcu)
2843 {
2844 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2845
2846 state->in_dev = NULL;
2847 state->dev = NULL;
2848 rcu_read_unlock();
2849 }
2850
2851 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2852 {
2853 if (v == SEQ_START_TOKEN)
2854 seq_puts(seq,
2855 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n");
2856 else {
2857 struct ip_mc_list *im = v;
2858 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2859 char *querier;
2860 long delta;
2861
2862 #ifdef CONFIG_IP_MULTICAST
2863 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2864 IGMP_V2_SEEN(state->in_dev) ? "V2" :
2865 "V3";
2866 #else
2867 querier = "NONE";
2868 #endif
2869
2870 if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2871 seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2872 state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2873 }
2874
2875 delta = im->timer.expires - jiffies;
2876 seq_printf(seq,
2877 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2878 im->multiaddr, im->users,
2879 im->tm_running,
2880 im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2881 im->reporter);
2882 }
2883 return 0;
2884 }
2885
2886 static const struct seq_operations igmp_mc_seq_ops = {
2887 .start = igmp_mc_seq_start,
2888 .next = igmp_mc_seq_next,
2889 .stop = igmp_mc_seq_stop,
2890 .show = igmp_mc_seq_show,
2891 };
2892
2893 struct igmp_mcf_iter_state {
2894 struct seq_net_private p;
2895 struct net_device *dev;
2896 struct in_device *idev;
2897 struct ip_mc_list *im;
2898 };
2899
2900 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private)
2901
2902 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2903 {
2904 struct net *net = seq_file_net(seq);
2905 struct ip_sf_list *psf = NULL;
2906 struct ip_mc_list *im = NULL;
2907 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2908
2909 state->idev = NULL;
2910 state->im = NULL;
2911 for_each_netdev_rcu(net, state->dev) {
2912 struct in_device *idev;
2913 idev = __in_dev_get_rcu(state->dev);
2914 if (unlikely(!idev))
2915 continue;
2916 im = rcu_dereference(idev->mc_list);
2917 if (likely(im)) {
2918 spin_lock_bh(&im->lock);
2919 psf = im->sources;
2920 if (likely(psf)) {
2921 state->im = im;
2922 state->idev = idev;
2923 break;
2924 }
2925 spin_unlock_bh(&im->lock);
2926 }
2927 }
2928 return psf;
2929 }
2930
2931 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2932 {
2933 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2934
2935 psf = psf->sf_next;
2936 while (!psf) {
2937 spin_unlock_bh(&state->im->lock);
2938 state->im = state->im->next;
2939 while (!state->im) {
2940 state->dev = next_net_device_rcu(state->dev);
2941 if (!state->dev) {
2942 state->idev = NULL;
2943 goto out;
2944 }
2945 state->idev = __in_dev_get_rcu(state->dev);
2946 if (!state->idev)
2947 continue;
2948 state->im = rcu_dereference(state->idev->mc_list);
2949 }
2950 spin_lock_bh(&state->im->lock);
2951 psf = state->im->sources;
2952 }
2953 out:
2954 return psf;
2955 }
2956
2957 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2958 {
2959 struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2960 if (psf)
2961 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2962 --pos;
2963 return pos ? NULL : psf;
2964 }
2965
2966 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2967 __acquires(rcu)
2968 {
2969 rcu_read_lock();
2970 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2971 }
2972
2973 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2974 {
2975 struct ip_sf_list *psf;
2976 if (v == SEQ_START_TOKEN)
2977 psf = igmp_mcf_get_first(seq);
2978 else
2979 psf = igmp_mcf_get_next(seq, v);
2980 ++*pos;
2981 return psf;
2982 }
2983
2984 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2985 __releases(rcu)
2986 {
2987 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2988 if (likely(state->im)) {
2989 spin_unlock_bh(&state->im->lock);
2990 state->im = NULL;
2991 }
2992 state->idev = NULL;
2993 state->dev = NULL;
2994 rcu_read_unlock();
2995 }
2996
2997 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2998 {
2999 struct ip_sf_list *psf = v;
3000 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
3001
3002 if (v == SEQ_START_TOKEN) {
3003 seq_puts(seq, "Idx Device MCA SRC INC EXC\n");
3004 } else {
3005 seq_printf(seq,
3006 "%3d %6.6s 0x%08x "
3007 "0x%08x %6lu %6lu\n",
3008 state->dev->ifindex, state->dev->name,
3009 ntohl(state->im->multiaddr),
3010 ntohl(psf->sf_inaddr),
3011 psf->sf_count[MCAST_INCLUDE],
3012 psf->sf_count[MCAST_EXCLUDE]);
3013 }
3014 return 0;
3015 }
3016
3017 static const struct seq_operations igmp_mcf_seq_ops = {
3018 .start = igmp_mcf_seq_start,
3019 .next = igmp_mcf_seq_next,
3020 .stop = igmp_mcf_seq_stop,
3021 .show = igmp_mcf_seq_show,
3022 };
3023
3024 static int __net_init igmp_net_init(struct net *net)
3025 {
3026 struct proc_dir_entry *pde;
3027 int err;
3028
3029 pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops,
3030 sizeof(struct igmp_mc_iter_state));
3031 if (!pde)
3032 goto out_igmp;
3033 pde = proc_create_net("mcfilter", 0444, net->proc_net,
3034 &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state));
3035 if (!pde)
3036 goto out_mcfilter;
3037 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3038 SOCK_DGRAM, 0, net);
3039 if (err < 0) {
3040 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3041 err);
3042 goto out_sock;
3043 }
3044
3045 return 0;
3046
3047 out_sock:
3048 remove_proc_entry("mcfilter", net->proc_net);
3049 out_mcfilter:
3050 remove_proc_entry("igmp", net->proc_net);
3051 out_igmp:
3052 return -ENOMEM;
3053 }
3054
3055 static void __net_exit igmp_net_exit(struct net *net)
3056 {
3057 remove_proc_entry("mcfilter", net->proc_net);
3058 remove_proc_entry("igmp", net->proc_net);
3059 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3060 }
3061
3062 static struct pernet_operations igmp_net_ops = {
3063 .init = igmp_net_init,
3064 .exit = igmp_net_exit,
3065 };
3066 #endif
3067
3068 static int igmp_netdev_event(struct notifier_block *this,
3069 unsigned long event, void *ptr)
3070 {
3071 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3072 struct in_device *in_dev;
3073
3074 switch (event) {
3075 case NETDEV_RESEND_IGMP:
3076 in_dev = __in_dev_get_rtnl(dev);
3077 if (in_dev)
3078 ip_mc_rejoin_groups(in_dev);
3079 break;
3080 default:
3081 break;
3082 }
3083 return NOTIFY_DONE;
3084 }
3085
3086 static struct notifier_block igmp_notifier = {
3087 .notifier_call = igmp_netdev_event,
3088 };
3089
3090 int __init igmp_mc_init(void)
3091 {
3092 #if defined(CONFIG_PROC_FS)
3093 int err;
3094
3095 err = register_pernet_subsys(&igmp_net_ops);
3096 if (err)
3097 return err;
3098 err = register_netdevice_notifier(&igmp_notifier);
3099 if (err)
3100 goto reg_notif_fail;
3101 return 0;
3102
3103 reg_notif_fail:
3104 unregister_pernet_subsys(&igmp_net_ops);
3105 return err;
3106 #else
3107 return register_netdevice_notifier(&igmp_notifier);
3108 #endif
3109 }
3110
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