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UBUNTU: Ubuntu-5.15.0-39.42
[mirror_ubuntu-jammy-kernel.git] / net / ipv4 / igmp.c
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(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(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 = prandom_u32() % max_delay;
217
218 im->tm_running = 1;
219 if (!mod_timer(&im->timer, jiffies+tv+2))
220 refcount_inc(&im->refcnt);
221 }
222
223 static void igmp_gq_start_timer(struct in_device *in_dev)
224 {
225 int tv = prandom_u32() % in_dev->mr_maxdelay;
226 unsigned long exp = jiffies + tv + 2;
227
228 if (in_dev->mr_gq_running &&
229 time_after_eq(exp, (in_dev->mr_gq_timer).expires))
230 return;
231
232 in_dev->mr_gq_running = 1;
233 if (!mod_timer(&in_dev->mr_gq_timer, exp))
234 in_dev_hold(in_dev);
235 }
236
237 static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
238 {
239 int tv = prandom_u32() % delay;
240
241 if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
242 in_dev_hold(in_dev);
243 }
244
245 static void igmp_mod_timer(struct ip_mc_list *im, int max_delay)
246 {
247 spin_lock_bh(&im->lock);
248 im->unsolicit_count = 0;
249 if (del_timer(&im->timer)) {
250 if ((long)(im->timer.expires-jiffies) < max_delay) {
251 add_timer(&im->timer);
252 im->tm_running = 1;
253 spin_unlock_bh(&im->lock);
254 return;
255 }
256 refcount_dec(&im->refcnt);
257 }
258 igmp_start_timer(im, max_delay);
259 spin_unlock_bh(&im->lock);
260 }
261
262
263 /*
264 * Send an IGMP report.
265 */
266
267 #define IGMP_SIZE (sizeof(struct igmphdr)+sizeof(struct iphdr)+4)
268
269
270 static int is_in(struct ip_mc_list *pmc, struct ip_sf_list *psf, int type,
271 int gdeleted, int sdeleted)
272 {
273 switch (type) {
274 case IGMPV3_MODE_IS_INCLUDE:
275 case IGMPV3_MODE_IS_EXCLUDE:
276 if (gdeleted || sdeleted)
277 return 0;
278 if (!(pmc->gsquery && !psf->sf_gsresp)) {
279 if (pmc->sfmode == MCAST_INCLUDE)
280 return 1;
281 /* don't include if this source is excluded
282 * in all filters
283 */
284 if (psf->sf_count[MCAST_INCLUDE])
285 return type == IGMPV3_MODE_IS_INCLUDE;
286 return pmc->sfcount[MCAST_EXCLUDE] ==
287 psf->sf_count[MCAST_EXCLUDE];
288 }
289 return 0;
290 case IGMPV3_CHANGE_TO_INCLUDE:
291 if (gdeleted || sdeleted)
292 return 0;
293 return psf->sf_count[MCAST_INCLUDE] != 0;
294 case IGMPV3_CHANGE_TO_EXCLUDE:
295 if (gdeleted || sdeleted)
296 return 0;
297 if (pmc->sfcount[MCAST_EXCLUDE] == 0 ||
298 psf->sf_count[MCAST_INCLUDE])
299 return 0;
300 return pmc->sfcount[MCAST_EXCLUDE] ==
301 psf->sf_count[MCAST_EXCLUDE];
302 case IGMPV3_ALLOW_NEW_SOURCES:
303 if (gdeleted || !psf->sf_crcount)
304 return 0;
305 return (pmc->sfmode == MCAST_INCLUDE) ^ sdeleted;
306 case IGMPV3_BLOCK_OLD_SOURCES:
307 if (pmc->sfmode == MCAST_INCLUDE)
308 return gdeleted || (psf->sf_crcount && sdeleted);
309 return psf->sf_crcount && !gdeleted && !sdeleted;
310 }
311 return 0;
312 }
313
314 static int
315 igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
316 {
317 struct ip_sf_list *psf;
318 int scount = 0;
319
320 for (psf = pmc->sources; psf; psf = psf->sf_next) {
321 if (!is_in(pmc, psf, type, gdeleted, sdeleted))
322 continue;
323 scount++;
324 }
325 return scount;
326 }
327
328 /* source address selection per RFC 3376 section 4.2.13 */
329 static __be32 igmpv3_get_srcaddr(struct net_device *dev,
330 const struct flowi4 *fl4)
331 {
332 struct in_device *in_dev = __in_dev_get_rcu(dev);
333 const struct in_ifaddr *ifa;
334
335 if (!in_dev)
336 return htonl(INADDR_ANY);
337
338 in_dev_for_each_ifa_rcu(ifa, in_dev) {
339 if (fl4->saddr == ifa->ifa_local)
340 return fl4->saddr;
341 }
342
343 return htonl(INADDR_ANY);
344 }
345
346 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
347 {
348 struct sk_buff *skb;
349 struct rtable *rt;
350 struct iphdr *pip;
351 struct igmpv3_report *pig;
352 struct net *net = dev_net(dev);
353 struct flowi4 fl4;
354 int hlen = LL_RESERVED_SPACE(dev);
355 int tlen = dev->needed_tailroom;
356 unsigned int size = mtu;
357
358 while (1) {
359 skb = alloc_skb(size + hlen + tlen,
360 GFP_ATOMIC | __GFP_NOWARN);
361 if (skb)
362 break;
363 size >>= 1;
364 if (size < 256)
365 return NULL;
366 }
367 skb->priority = TC_PRIO_CONTROL;
368
369 rt = ip_route_output_ports(net, &fl4, NULL, IGMPV3_ALL_MCR, 0,
370 0, 0,
371 IPPROTO_IGMP, 0, dev->ifindex);
372 if (IS_ERR(rt)) {
373 kfree_skb(skb);
374 return NULL;
375 }
376
377 skb_dst_set(skb, &rt->dst);
378 skb->dev = dev;
379
380 skb_reserve(skb, hlen);
381 skb_tailroom_reserve(skb, mtu, tlen);
382
383 skb_reset_network_header(skb);
384 pip = ip_hdr(skb);
385 skb_put(skb, sizeof(struct iphdr) + 4);
386
387 pip->version = 4;
388 pip->ihl = (sizeof(struct iphdr)+4)>>2;
389 pip->tos = 0xc0;
390 pip->frag_off = htons(IP_DF);
391 pip->ttl = 1;
392 pip->daddr = fl4.daddr;
393
394 rcu_read_lock();
395 pip->saddr = igmpv3_get_srcaddr(dev, &fl4);
396 rcu_read_unlock();
397
398 pip->protocol = IPPROTO_IGMP;
399 pip->tot_len = 0; /* filled in later */
400 ip_select_ident(net, skb, NULL);
401 ((u8 *)&pip[1])[0] = IPOPT_RA;
402 ((u8 *)&pip[1])[1] = 4;
403 ((u8 *)&pip[1])[2] = 0;
404 ((u8 *)&pip[1])[3] = 0;
405
406 skb->transport_header = skb->network_header + sizeof(struct iphdr) + 4;
407 skb_put(skb, sizeof(*pig));
408 pig = igmpv3_report_hdr(skb);
409 pig->type = IGMPV3_HOST_MEMBERSHIP_REPORT;
410 pig->resv1 = 0;
411 pig->csum = 0;
412 pig->resv2 = 0;
413 pig->ngrec = 0;
414 return skb;
415 }
416
417 static int igmpv3_sendpack(struct sk_buff *skb)
418 {
419 struct igmphdr *pig = igmp_hdr(skb);
420 const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
421
422 pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
423
424 return ip_local_out(dev_net(skb_dst(skb)->dev), skb->sk, skb);
425 }
426
427 static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
428 {
429 return sizeof(struct igmpv3_grec) + 4*igmp_scount(pmc, type, gdel, sdel);
430 }
431
432 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
433 int type, struct igmpv3_grec **ppgr, unsigned int mtu)
434 {
435 struct net_device *dev = pmc->interface->dev;
436 struct igmpv3_report *pih;
437 struct igmpv3_grec *pgr;
438
439 if (!skb) {
440 skb = igmpv3_newpack(dev, mtu);
441 if (!skb)
442 return NULL;
443 }
444 pgr = skb_put(skb, sizeof(struct igmpv3_grec));
445 pgr->grec_type = type;
446 pgr->grec_auxwords = 0;
447 pgr->grec_nsrcs = 0;
448 pgr->grec_mca = pmc->multiaddr;
449 pih = igmpv3_report_hdr(skb);
450 pih->ngrec = htons(ntohs(pih->ngrec)+1);
451 *ppgr = pgr;
452 return skb;
453 }
454
455 #define AVAILABLE(skb) ((skb) ? skb_availroom(skb) : 0)
456
457 static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
458 int type, int gdeleted, int sdeleted)
459 {
460 struct net_device *dev = pmc->interface->dev;
461 struct net *net = dev_net(dev);
462 struct igmpv3_report *pih;
463 struct igmpv3_grec *pgr = NULL;
464 struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
465 int scount, stotal, first, isquery, truncate;
466 unsigned int mtu;
467
468 if (pmc->multiaddr == IGMP_ALL_HOSTS)
469 return skb;
470 if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
471 return skb;
472
473 mtu = READ_ONCE(dev->mtu);
474 if (mtu < IPV4_MIN_MTU)
475 return skb;
476
477 isquery = type == IGMPV3_MODE_IS_INCLUDE ||
478 type == IGMPV3_MODE_IS_EXCLUDE;
479 truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
480 type == IGMPV3_CHANGE_TO_EXCLUDE;
481
482 stotal = scount = 0;
483
484 psf_list = sdeleted ? &pmc->tomb : &pmc->sources;
485
486 if (!*psf_list)
487 goto empty_source;
488
489 pih = skb ? igmpv3_report_hdr(skb) : NULL;
490
491 /* EX and TO_EX get a fresh packet, if needed */
492 if (truncate) {
493 if (pih && pih->ngrec &&
494 AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
495 if (skb)
496 igmpv3_sendpack(skb);
497 skb = igmpv3_newpack(dev, mtu);
498 }
499 }
500 first = 1;
501 psf_prev = NULL;
502 for (psf = *psf_list; psf; psf = psf_next) {
503 __be32 *psrc;
504
505 psf_next = psf->sf_next;
506
507 if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
508 psf_prev = psf;
509 continue;
510 }
511
512 /* Based on RFC3376 5.1. Should not send source-list change
513 * records when there is a filter mode change.
514 */
515 if (((gdeleted && pmc->sfmode == MCAST_EXCLUDE) ||
516 (!gdeleted && pmc->crcount)) &&
517 (type == IGMPV3_ALLOW_NEW_SOURCES ||
518 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount)
519 goto decrease_sf_crcount;
520
521 /* clear marks on query responses */
522 if (isquery)
523 psf->sf_gsresp = 0;
524
525 if (AVAILABLE(skb) < sizeof(__be32) +
526 first*sizeof(struct igmpv3_grec)) {
527 if (truncate && !first)
528 break; /* truncate these */
529 if (pgr)
530 pgr->grec_nsrcs = htons(scount);
531 if (skb)
532 igmpv3_sendpack(skb);
533 skb = igmpv3_newpack(dev, mtu);
534 first = 1;
535 scount = 0;
536 }
537 if (first) {
538 skb = add_grhead(skb, pmc, type, &pgr, mtu);
539 first = 0;
540 }
541 if (!skb)
542 return NULL;
543 psrc = skb_put(skb, sizeof(__be32));
544 *psrc = psf->sf_inaddr;
545 scount++; stotal++;
546 if ((type == IGMPV3_ALLOW_NEW_SOURCES ||
547 type == IGMPV3_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
548 decrease_sf_crcount:
549 psf->sf_crcount--;
550 if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
551 if (psf_prev)
552 psf_prev->sf_next = psf->sf_next;
553 else
554 *psf_list = psf->sf_next;
555 kfree(psf);
556 continue;
557 }
558 }
559 psf_prev = psf;
560 }
561
562 empty_source:
563 if (!stotal) {
564 if (type == IGMPV3_ALLOW_NEW_SOURCES ||
565 type == IGMPV3_BLOCK_OLD_SOURCES)
566 return skb;
567 if (pmc->crcount || isquery) {
568 /* make sure we have room for group header */
569 if (skb && AVAILABLE(skb) < sizeof(struct igmpv3_grec)) {
570 igmpv3_sendpack(skb);
571 skb = NULL; /* add_grhead will get a new one */
572 }
573 skb = add_grhead(skb, pmc, type, &pgr, mtu);
574 }
575 }
576 if (pgr)
577 pgr->grec_nsrcs = htons(scount);
578
579 if (isquery)
580 pmc->gsquery = 0; /* clear query state on report */
581 return skb;
582 }
583
584 static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
585 {
586 struct sk_buff *skb = NULL;
587 struct net *net = dev_net(in_dev->dev);
588 int type;
589
590 if (!pmc) {
591 rcu_read_lock();
592 for_each_pmc_rcu(in_dev, pmc) {
593 if (pmc->multiaddr == IGMP_ALL_HOSTS)
594 continue;
595 if (ipv4_is_local_multicast(pmc->multiaddr) &&
596 !net->ipv4.sysctl_igmp_llm_reports)
597 continue;
598 spin_lock_bh(&pmc->lock);
599 if (pmc->sfcount[MCAST_EXCLUDE])
600 type = IGMPV3_MODE_IS_EXCLUDE;
601 else
602 type = IGMPV3_MODE_IS_INCLUDE;
603 skb = add_grec(skb, pmc, type, 0, 0);
604 spin_unlock_bh(&pmc->lock);
605 }
606 rcu_read_unlock();
607 } else {
608 spin_lock_bh(&pmc->lock);
609 if (pmc->sfcount[MCAST_EXCLUDE])
610 type = IGMPV3_MODE_IS_EXCLUDE;
611 else
612 type = IGMPV3_MODE_IS_INCLUDE;
613 skb = add_grec(skb, pmc, type, 0, 0);
614 spin_unlock_bh(&pmc->lock);
615 }
616 if (!skb)
617 return 0;
618 return igmpv3_sendpack(skb);
619 }
620
621 /*
622 * remove zero-count source records from a source filter list
623 */
624 static void igmpv3_clear_zeros(struct ip_sf_list **ppsf)
625 {
626 struct ip_sf_list *psf_prev, *psf_next, *psf;
627
628 psf_prev = NULL;
629 for (psf = *ppsf; psf; psf = psf_next) {
630 psf_next = psf->sf_next;
631 if (psf->sf_crcount == 0) {
632 if (psf_prev)
633 psf_prev->sf_next = psf->sf_next;
634 else
635 *ppsf = psf->sf_next;
636 kfree(psf);
637 } else
638 psf_prev = psf;
639 }
640 }
641
642 static void kfree_pmc(struct ip_mc_list *pmc)
643 {
644 ip_sf_list_clear_all(pmc->sources);
645 ip_sf_list_clear_all(pmc->tomb);
646 kfree(pmc);
647 }
648
649 static void igmpv3_send_cr(struct in_device *in_dev)
650 {
651 struct ip_mc_list *pmc, *pmc_prev, *pmc_next;
652 struct sk_buff *skb = NULL;
653 int type, dtype;
654
655 rcu_read_lock();
656 spin_lock_bh(&in_dev->mc_tomb_lock);
657
658 /* deleted MCA's */
659 pmc_prev = NULL;
660 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc_next) {
661 pmc_next = pmc->next;
662 if (pmc->sfmode == MCAST_INCLUDE) {
663 type = IGMPV3_BLOCK_OLD_SOURCES;
664 dtype = IGMPV3_BLOCK_OLD_SOURCES;
665 skb = add_grec(skb, pmc, type, 1, 0);
666 skb = add_grec(skb, pmc, dtype, 1, 1);
667 }
668 if (pmc->crcount) {
669 if (pmc->sfmode == MCAST_EXCLUDE) {
670 type = IGMPV3_CHANGE_TO_INCLUDE;
671 skb = add_grec(skb, pmc, type, 1, 0);
672 }
673 pmc->crcount--;
674 if (pmc->crcount == 0) {
675 igmpv3_clear_zeros(&pmc->tomb);
676 igmpv3_clear_zeros(&pmc->sources);
677 }
678 }
679 if (pmc->crcount == 0 && !pmc->tomb && !pmc->sources) {
680 if (pmc_prev)
681 pmc_prev->next = pmc_next;
682 else
683 in_dev->mc_tomb = pmc_next;
684 in_dev_put(pmc->interface);
685 kfree_pmc(pmc);
686 } else
687 pmc_prev = pmc;
688 }
689 spin_unlock_bh(&in_dev->mc_tomb_lock);
690
691 /* change recs */
692 for_each_pmc_rcu(in_dev, pmc) {
693 spin_lock_bh(&pmc->lock);
694 if (pmc->sfcount[MCAST_EXCLUDE]) {
695 type = IGMPV3_BLOCK_OLD_SOURCES;
696 dtype = IGMPV3_ALLOW_NEW_SOURCES;
697 } else {
698 type = IGMPV3_ALLOW_NEW_SOURCES;
699 dtype = IGMPV3_BLOCK_OLD_SOURCES;
700 }
701 skb = add_grec(skb, pmc, type, 0, 0);
702 skb = add_grec(skb, pmc, dtype, 0, 1); /* deleted sources */
703
704 /* filter mode changes */
705 if (pmc->crcount) {
706 if (pmc->sfmode == MCAST_EXCLUDE)
707 type = IGMPV3_CHANGE_TO_EXCLUDE;
708 else
709 type = IGMPV3_CHANGE_TO_INCLUDE;
710 skb = add_grec(skb, pmc, type, 0, 0);
711 pmc->crcount--;
712 }
713 spin_unlock_bh(&pmc->lock);
714 }
715 rcu_read_unlock();
716
717 if (!skb)
718 return;
719 (void) igmpv3_sendpack(skb);
720 }
721
722 static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
723 int type)
724 {
725 struct sk_buff *skb;
726 struct iphdr *iph;
727 struct igmphdr *ih;
728 struct rtable *rt;
729 struct net_device *dev = in_dev->dev;
730 struct net *net = dev_net(dev);
731 __be32 group = pmc ? pmc->multiaddr : 0;
732 struct flowi4 fl4;
733 __be32 dst;
734 int hlen, tlen;
735
736 if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
737 return igmpv3_send_report(in_dev, pmc);
738
739 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
740 return 0;
741
742 if (type == IGMP_HOST_LEAVE_MESSAGE)
743 dst = IGMP_ALL_ROUTER;
744 else
745 dst = group;
746
747 rt = ip_route_output_ports(net, &fl4, NULL, dst, 0,
748 0, 0,
749 IPPROTO_IGMP, 0, dev->ifindex);
750 if (IS_ERR(rt))
751 return -1;
752
753 hlen = LL_RESERVED_SPACE(dev);
754 tlen = dev->needed_tailroom;
755 skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
756 if (!skb) {
757 ip_rt_put(rt);
758 return -1;
759 }
760 skb->priority = TC_PRIO_CONTROL;
761
762 skb_dst_set(skb, &rt->dst);
763
764 skb_reserve(skb, hlen);
765
766 skb_reset_network_header(skb);
767 iph = ip_hdr(skb);
768 skb_put(skb, sizeof(struct iphdr) + 4);
769
770 iph->version = 4;
771 iph->ihl = (sizeof(struct iphdr)+4)>>2;
772 iph->tos = 0xc0;
773 iph->frag_off = htons(IP_DF);
774 iph->ttl = 1;
775 iph->daddr = dst;
776 iph->saddr = fl4.saddr;
777 iph->protocol = IPPROTO_IGMP;
778 ip_select_ident(net, skb, NULL);
779 ((u8 *)&iph[1])[0] = IPOPT_RA;
780 ((u8 *)&iph[1])[1] = 4;
781 ((u8 *)&iph[1])[2] = 0;
782 ((u8 *)&iph[1])[3] = 0;
783
784 ih = skb_put(skb, sizeof(struct igmphdr));
785 ih->type = type;
786 ih->code = 0;
787 ih->csum = 0;
788 ih->group = group;
789 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
790
791 return ip_local_out(net, skb->sk, skb);
792 }
793
794 static void igmp_gq_timer_expire(struct timer_list *t)
795 {
796 struct in_device *in_dev = from_timer(in_dev, t, mr_gq_timer);
797
798 in_dev->mr_gq_running = 0;
799 igmpv3_send_report(in_dev, NULL);
800 in_dev_put(in_dev);
801 }
802
803 static void igmp_ifc_timer_expire(struct timer_list *t)
804 {
805 struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
806 u32 mr_ifc_count;
807
808 igmpv3_send_cr(in_dev);
809 restart:
810 mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count);
811
812 if (mr_ifc_count) {
813 if (cmpxchg(&in_dev->mr_ifc_count,
814 mr_ifc_count,
815 mr_ifc_count - 1) != mr_ifc_count)
816 goto restart;
817 igmp_ifc_start_timer(in_dev,
818 unsolicited_report_interval(in_dev));
819 }
820 in_dev_put(in_dev);
821 }
822
823 static void igmp_ifc_event(struct in_device *in_dev)
824 {
825 struct net *net = dev_net(in_dev->dev);
826 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
827 return;
828 WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv);
829 igmp_ifc_start_timer(in_dev, 1);
830 }
831
832
833 static void igmp_timer_expire(struct timer_list *t)
834 {
835 struct ip_mc_list *im = from_timer(im, t, timer);
836 struct in_device *in_dev = im->interface;
837
838 spin_lock(&im->lock);
839 im->tm_running = 0;
840
841 if (im->unsolicit_count && --im->unsolicit_count)
842 igmp_start_timer(im, unsolicited_report_interval(in_dev));
843
844 im->reporter = 1;
845 spin_unlock(&im->lock);
846
847 if (IGMP_V1_SEEN(in_dev))
848 igmp_send_report(in_dev, im, IGMP_HOST_MEMBERSHIP_REPORT);
849 else if (IGMP_V2_SEEN(in_dev))
850 igmp_send_report(in_dev, im, IGMPV2_HOST_MEMBERSHIP_REPORT);
851 else
852 igmp_send_report(in_dev, im, IGMPV3_HOST_MEMBERSHIP_REPORT);
853
854 ip_ma_put(im);
855 }
856
857 /* mark EXCLUDE-mode sources */
858 static int igmp_xmarksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
859 {
860 struct ip_sf_list *psf;
861 int i, scount;
862
863 scount = 0;
864 for (psf = pmc->sources; psf; psf = psf->sf_next) {
865 if (scount == nsrcs)
866 break;
867 for (i = 0; i < nsrcs; i++) {
868 /* skip inactive filters */
869 if (psf->sf_count[MCAST_INCLUDE] ||
870 pmc->sfcount[MCAST_EXCLUDE] !=
871 psf->sf_count[MCAST_EXCLUDE])
872 break;
873 if (srcs[i] == psf->sf_inaddr) {
874 scount++;
875 break;
876 }
877 }
878 }
879 pmc->gsquery = 0;
880 if (scount == nsrcs) /* all sources excluded */
881 return 0;
882 return 1;
883 }
884
885 static int igmp_marksources(struct ip_mc_list *pmc, int nsrcs, __be32 *srcs)
886 {
887 struct ip_sf_list *psf;
888 int i, scount;
889
890 if (pmc->sfmode == MCAST_EXCLUDE)
891 return igmp_xmarksources(pmc, nsrcs, srcs);
892
893 /* mark INCLUDE-mode sources */
894 scount = 0;
895 for (psf = pmc->sources; psf; psf = psf->sf_next) {
896 if (scount == nsrcs)
897 break;
898 for (i = 0; i < nsrcs; i++)
899 if (srcs[i] == psf->sf_inaddr) {
900 psf->sf_gsresp = 1;
901 scount++;
902 break;
903 }
904 }
905 if (!scount) {
906 pmc->gsquery = 0;
907 return 0;
908 }
909 pmc->gsquery = 1;
910 return 1;
911 }
912
913 /* return true if packet was dropped */
914 static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
915 {
916 struct ip_mc_list *im;
917 struct net *net = dev_net(in_dev->dev);
918
919 /* Timers are only set for non-local groups */
920
921 if (group == IGMP_ALL_HOSTS)
922 return false;
923 if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
924 return false;
925
926 rcu_read_lock();
927 for_each_pmc_rcu(in_dev, im) {
928 if (im->multiaddr == group) {
929 igmp_stop_timer(im);
930 break;
931 }
932 }
933 rcu_read_unlock();
934 return false;
935 }
936
937 /* return true if packet was dropped */
938 static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
939 int len)
940 {
941 struct igmphdr *ih = igmp_hdr(skb);
942 struct igmpv3_query *ih3 = igmpv3_query_hdr(skb);
943 struct ip_mc_list *im;
944 __be32 group = ih->group;
945 int max_delay;
946 int mark = 0;
947 struct net *net = dev_net(in_dev->dev);
948
949
950 if (len == 8) {
951 if (ih->code == 0) {
952 /* Alas, old v1 router presents here. */
953
954 max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
955 in_dev->mr_v1_seen = jiffies +
956 (in_dev->mr_qrv * in_dev->mr_qi) +
957 in_dev->mr_qri;
958 group = 0;
959 } else {
960 /* v2 router present */
961 max_delay = ih->code*(HZ/IGMP_TIMER_SCALE);
962 in_dev->mr_v2_seen = jiffies +
963 (in_dev->mr_qrv * in_dev->mr_qi) +
964 in_dev->mr_qri;
965 }
966 /* cancel the interface change timer */
967 WRITE_ONCE(in_dev->mr_ifc_count, 0);
968 if (del_timer(&in_dev->mr_ifc_timer))
969 __in_dev_put(in_dev);
970 /* clear deleted report items */
971 igmpv3_clear_delrec(in_dev);
972 } else if (len < 12) {
973 return true; /* ignore bogus packet; freed by caller */
974 } else if (IGMP_V1_SEEN(in_dev)) {
975 /* This is a v3 query with v1 queriers present */
976 max_delay = IGMP_QUERY_RESPONSE_INTERVAL;
977 group = 0;
978 } else if (IGMP_V2_SEEN(in_dev)) {
979 /* this is a v3 query with v2 queriers present;
980 * Interpretation of the max_delay code is problematic here.
981 * A real v2 host would use ih_code directly, while v3 has a
982 * different encoding. We use the v3 encoding as more likely
983 * to be intended in a v3 query.
984 */
985 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
986 if (!max_delay)
987 max_delay = 1; /* can't mod w/ 0 */
988 } else { /* v3 */
989 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)))
990 return true;
991
992 ih3 = igmpv3_query_hdr(skb);
993 if (ih3->nsrcs) {
994 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query)
995 + ntohs(ih3->nsrcs)*sizeof(__be32)))
996 return true;
997 ih3 = igmpv3_query_hdr(skb);
998 }
999
1000 max_delay = IGMPV3_MRC(ih3->code)*(HZ/IGMP_TIMER_SCALE);
1001 if (!max_delay)
1002 max_delay = 1; /* can't mod w/ 0 */
1003 in_dev->mr_maxdelay = max_delay;
1004
1005 /* RFC3376, 4.1.6. QRV and 4.1.7. QQIC, when the most recently
1006 * received value was zero, use the default or statically
1007 * configured value.
1008 */
1009 in_dev->mr_qrv = ih3->qrv ?: net->ipv4.sysctl_igmp_qrv;
1010 in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
1011
1012 /* RFC3376, 8.3. Query Response Interval:
1013 * The number of seconds represented by the [Query Response
1014 * Interval] must be less than the [Query Interval].
1015 */
1016 if (in_dev->mr_qri >= in_dev->mr_qi)
1017 in_dev->mr_qri = (in_dev->mr_qi/HZ - 1)*HZ;
1018
1019 if (!group) { /* general query */
1020 if (ih3->nsrcs)
1021 return true; /* no sources allowed */
1022 igmp_gq_start_timer(in_dev);
1023 return false;
1024 }
1025 /* mark sources to include, if group & source-specific */
1026 mark = ih3->nsrcs != 0;
1027 }
1028
1029 /*
1030 * - Start the timers in all of our membership records
1031 * that the query applies to for the interface on
1032 * which the query arrived excl. those that belong
1033 * to a "local" group (224.0.0.X)
1034 * - For timers already running check if they need to
1035 * be reset.
1036 * - Use the igmp->igmp_code field as the maximum
1037 * delay possible
1038 */
1039 rcu_read_lock();
1040 for_each_pmc_rcu(in_dev, im) {
1041 int changed;
1042
1043 if (group && group != im->multiaddr)
1044 continue;
1045 if (im->multiaddr == IGMP_ALL_HOSTS)
1046 continue;
1047 if (ipv4_is_local_multicast(im->multiaddr) &&
1048 !net->ipv4.sysctl_igmp_llm_reports)
1049 continue;
1050 spin_lock_bh(&im->lock);
1051 if (im->tm_running)
1052 im->gsquery = im->gsquery && mark;
1053 else
1054 im->gsquery = mark;
1055 changed = !im->gsquery ||
1056 igmp_marksources(im, ntohs(ih3->nsrcs), ih3->srcs);
1057 spin_unlock_bh(&im->lock);
1058 if (changed)
1059 igmp_mod_timer(im, max_delay);
1060 }
1061 rcu_read_unlock();
1062 return false;
1063 }
1064
1065 /* called in rcu_read_lock() section */
1066 int igmp_rcv(struct sk_buff *skb)
1067 {
1068 /* This basically follows the spec line by line -- see RFC1112 */
1069 struct igmphdr *ih;
1070 struct net_device *dev = skb->dev;
1071 struct in_device *in_dev;
1072 int len = skb->len;
1073 bool dropped = true;
1074
1075 if (netif_is_l3_master(dev)) {
1076 dev = dev_get_by_index_rcu(dev_net(dev), IPCB(skb)->iif);
1077 if (!dev)
1078 goto drop;
1079 }
1080
1081 in_dev = __in_dev_get_rcu(dev);
1082 if (!in_dev)
1083 goto drop;
1084
1085 if (!pskb_may_pull(skb, sizeof(struct igmphdr)))
1086 goto drop;
1087
1088 if (skb_checksum_simple_validate(skb))
1089 goto drop;
1090
1091 ih = igmp_hdr(skb);
1092 switch (ih->type) {
1093 case IGMP_HOST_MEMBERSHIP_QUERY:
1094 dropped = igmp_heard_query(in_dev, skb, len);
1095 break;
1096 case IGMP_HOST_MEMBERSHIP_REPORT:
1097 case IGMPV2_HOST_MEMBERSHIP_REPORT:
1098 /* Is it our report looped back? */
1099 if (rt_is_output_route(skb_rtable(skb)))
1100 break;
1101 /* don't rely on MC router hearing unicast reports */
1102 if (skb->pkt_type == PACKET_MULTICAST ||
1103 skb->pkt_type == PACKET_BROADCAST)
1104 dropped = igmp_heard_report(in_dev, ih->group);
1105 break;
1106 case IGMP_PIM:
1107 #ifdef CONFIG_IP_PIMSM_V1
1108 return pim_rcv_v1(skb);
1109 #endif
1110 case IGMPV3_HOST_MEMBERSHIP_REPORT:
1111 case IGMP_DVMRP:
1112 case IGMP_TRACE:
1113 case IGMP_HOST_LEAVE_MESSAGE:
1114 case IGMP_MTRACE:
1115 case IGMP_MTRACE_RESP:
1116 break;
1117 default:
1118 break;
1119 }
1120
1121 drop:
1122 if (dropped)
1123 kfree_skb(skb);
1124 else
1125 consume_skb(skb);
1126 return 0;
1127 }
1128
1129 #endif
1130
1131
1132 /*
1133 * Add a filter to a device
1134 */
1135
1136 static void ip_mc_filter_add(struct in_device *in_dev, __be32 addr)
1137 {
1138 char buf[MAX_ADDR_LEN];
1139 struct net_device *dev = in_dev->dev;
1140
1141 /* Checking for IFF_MULTICAST here is WRONG-WRONG-WRONG.
1142 We will get multicast token leakage, when IFF_MULTICAST
1143 is changed. This check should be done in ndo_set_rx_mode
1144 routine. Something sort of:
1145 if (dev->mc_list && dev->flags&IFF_MULTICAST) { do it; }
1146 --ANK
1147 */
1148 if (arp_mc_map(addr, buf, dev, 0) == 0)
1149 dev_mc_add(dev, buf);
1150 }
1151
1152 /*
1153 * Remove a filter from a device
1154 */
1155
1156 static void ip_mc_filter_del(struct in_device *in_dev, __be32 addr)
1157 {
1158 char buf[MAX_ADDR_LEN];
1159 struct net_device *dev = in_dev->dev;
1160
1161 if (arp_mc_map(addr, buf, dev, 0) == 0)
1162 dev_mc_del(dev, buf);
1163 }
1164
1165 #ifdef CONFIG_IP_MULTICAST
1166 /*
1167 * deleted ip_mc_list manipulation
1168 */
1169 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
1170 gfp_t gfp)
1171 {
1172 struct ip_mc_list *pmc;
1173 struct net *net = dev_net(in_dev->dev);
1174
1175 /* this is an "ip_mc_list" for convenience; only the fields below
1176 * are actually used. In particular, the refcnt and users are not
1177 * used for management of the delete list. Using the same structure
1178 * for deleted items allows change reports to use common code with
1179 * non-deleted or query-response MCA's.
1180 */
1181 pmc = kzalloc(sizeof(*pmc), gfp);
1182 if (!pmc)
1183 return;
1184 spin_lock_init(&pmc->lock);
1185 spin_lock_bh(&im->lock);
1186 pmc->interface = im->interface;
1187 in_dev_hold(in_dev);
1188 pmc->multiaddr = im->multiaddr;
1189 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1190 pmc->sfmode = im->sfmode;
1191 if (pmc->sfmode == MCAST_INCLUDE) {
1192 struct ip_sf_list *psf;
1193
1194 pmc->tomb = im->tomb;
1195 pmc->sources = im->sources;
1196 im->tomb = im->sources = NULL;
1197 for (psf = pmc->sources; psf; psf = psf->sf_next)
1198 psf->sf_crcount = pmc->crcount;
1199 }
1200 spin_unlock_bh(&im->lock);
1201
1202 spin_lock_bh(&in_dev->mc_tomb_lock);
1203 pmc->next = in_dev->mc_tomb;
1204 in_dev->mc_tomb = pmc;
1205 spin_unlock_bh(&in_dev->mc_tomb_lock);
1206 }
1207
1208 /*
1209 * restore ip_mc_list deleted records
1210 */
1211 static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
1212 {
1213 struct ip_mc_list *pmc, *pmc_prev;
1214 struct ip_sf_list *psf;
1215 struct net *net = dev_net(in_dev->dev);
1216 __be32 multiaddr = im->multiaddr;
1217
1218 spin_lock_bh(&in_dev->mc_tomb_lock);
1219 pmc_prev = NULL;
1220 for (pmc = in_dev->mc_tomb; pmc; pmc = pmc->next) {
1221 if (pmc->multiaddr == multiaddr)
1222 break;
1223 pmc_prev = pmc;
1224 }
1225 if (pmc) {
1226 if (pmc_prev)
1227 pmc_prev->next = pmc->next;
1228 else
1229 in_dev->mc_tomb = pmc->next;
1230 }
1231 spin_unlock_bh(&in_dev->mc_tomb_lock);
1232
1233 spin_lock_bh(&im->lock);
1234 if (pmc) {
1235 im->interface = pmc->interface;
1236 if (im->sfmode == MCAST_INCLUDE) {
1237 swap(im->tomb, pmc->tomb);
1238 swap(im->sources, pmc->sources);
1239 for (psf = im->sources; psf; psf = psf->sf_next)
1240 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1241 } else {
1242 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1243 }
1244 in_dev_put(pmc->interface);
1245 kfree_pmc(pmc);
1246 }
1247 spin_unlock_bh(&im->lock);
1248 }
1249
1250 /*
1251 * flush ip_mc_list deleted records
1252 */
1253 static void igmpv3_clear_delrec(struct in_device *in_dev)
1254 {
1255 struct ip_mc_list *pmc, *nextpmc;
1256
1257 spin_lock_bh(&in_dev->mc_tomb_lock);
1258 pmc = in_dev->mc_tomb;
1259 in_dev->mc_tomb = NULL;
1260 spin_unlock_bh(&in_dev->mc_tomb_lock);
1261
1262 for (; pmc; pmc = nextpmc) {
1263 nextpmc = pmc->next;
1264 ip_mc_clear_src(pmc);
1265 in_dev_put(pmc->interface);
1266 kfree_pmc(pmc);
1267 }
1268 /* clear dead sources, too */
1269 rcu_read_lock();
1270 for_each_pmc_rcu(in_dev, pmc) {
1271 struct ip_sf_list *psf;
1272
1273 spin_lock_bh(&pmc->lock);
1274 psf = pmc->tomb;
1275 pmc->tomb = NULL;
1276 spin_unlock_bh(&pmc->lock);
1277 ip_sf_list_clear_all(psf);
1278 }
1279 rcu_read_unlock();
1280 }
1281 #endif
1282
1283 static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
1284 {
1285 struct in_device *in_dev = im->interface;
1286 #ifdef CONFIG_IP_MULTICAST
1287 struct net *net = dev_net(in_dev->dev);
1288 int reporter;
1289 #endif
1290
1291 if (im->loaded) {
1292 im->loaded = 0;
1293 ip_mc_filter_del(in_dev, im->multiaddr);
1294 }
1295
1296 #ifdef CONFIG_IP_MULTICAST
1297 if (im->multiaddr == IGMP_ALL_HOSTS)
1298 return;
1299 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1300 return;
1301
1302 reporter = im->reporter;
1303 igmp_stop_timer(im);
1304
1305 if (!in_dev->dead) {
1306 if (IGMP_V1_SEEN(in_dev))
1307 return;
1308 if (IGMP_V2_SEEN(in_dev)) {
1309 if (reporter)
1310 igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
1311 return;
1312 }
1313 /* IGMPv3 */
1314 igmpv3_add_delrec(in_dev, im, gfp);
1315
1316 igmp_ifc_event(in_dev);
1317 }
1318 #endif
1319 }
1320
1321 static void igmp_group_dropped(struct ip_mc_list *im)
1322 {
1323 __igmp_group_dropped(im, GFP_KERNEL);
1324 }
1325
1326 static void igmp_group_added(struct ip_mc_list *im)
1327 {
1328 struct in_device *in_dev = im->interface;
1329 #ifdef CONFIG_IP_MULTICAST
1330 struct net *net = dev_net(in_dev->dev);
1331 #endif
1332
1333 if (im->loaded == 0) {
1334 im->loaded = 1;
1335 ip_mc_filter_add(in_dev, im->multiaddr);
1336 }
1337
1338 #ifdef CONFIG_IP_MULTICAST
1339 if (im->multiaddr == IGMP_ALL_HOSTS)
1340 return;
1341 if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
1342 return;
1343
1344 if (in_dev->dead)
1345 return;
1346
1347 im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
1348 if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
1349 spin_lock_bh(&im->lock);
1350 igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
1351 spin_unlock_bh(&im->lock);
1352 return;
1353 }
1354 /* else, v3 */
1355
1356 /* Based on RFC3376 5.1, for newly added INCLUDE SSM, we should
1357 * not send filter-mode change record as the mode should be from
1358 * IN() to IN(A).
1359 */
1360 if (im->sfmode == MCAST_EXCLUDE)
1361 im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1362
1363 igmp_ifc_event(in_dev);
1364 #endif
1365 }
1366
1367
1368 /*
1369 * Multicast list managers
1370 */
1371
1372 static u32 ip_mc_hash(const struct ip_mc_list *im)
1373 {
1374 return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
1375 }
1376
1377 static void ip_mc_hash_add(struct in_device *in_dev,
1378 struct ip_mc_list *im)
1379 {
1380 struct ip_mc_list __rcu **mc_hash;
1381 u32 hash;
1382
1383 mc_hash = rtnl_dereference(in_dev->mc_hash);
1384 if (mc_hash) {
1385 hash = ip_mc_hash(im);
1386 im->next_hash = mc_hash[hash];
1387 rcu_assign_pointer(mc_hash[hash], im);
1388 return;
1389 }
1390
1391 /* do not use a hash table for small number of items */
1392 if (in_dev->mc_count < 4)
1393 return;
1394
1395 mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
1396 GFP_KERNEL);
1397 if (!mc_hash)
1398 return;
1399
1400 for_each_pmc_rtnl(in_dev, im) {
1401 hash = ip_mc_hash(im);
1402 im->next_hash = mc_hash[hash];
1403 RCU_INIT_POINTER(mc_hash[hash], im);
1404 }
1405
1406 rcu_assign_pointer(in_dev->mc_hash, mc_hash);
1407 }
1408
1409 static void ip_mc_hash_remove(struct in_device *in_dev,
1410 struct ip_mc_list *im)
1411 {
1412 struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
1413 struct ip_mc_list *aux;
1414
1415 if (!mc_hash)
1416 return;
1417 mc_hash += ip_mc_hash(im);
1418 while ((aux = rtnl_dereference(*mc_hash)) != im)
1419 mc_hash = &aux->next_hash;
1420 *mc_hash = im->next_hash;
1421 }
1422
1423
1424 /*
1425 * A socket has joined a multicast group on device dev.
1426 */
1427 static void ____ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
1428 unsigned int mode, gfp_t gfp)
1429 {
1430 struct ip_mc_list *im;
1431
1432 ASSERT_RTNL();
1433
1434 for_each_pmc_rtnl(in_dev, im) {
1435 if (im->multiaddr == addr) {
1436 im->users++;
1437 ip_mc_add_src(in_dev, &addr, mode, 0, NULL, 0);
1438 goto out;
1439 }
1440 }
1441
1442 im = kzalloc(sizeof(*im), gfp);
1443 if (!im)
1444 goto out;
1445
1446 im->users = 1;
1447 im->interface = in_dev;
1448 in_dev_hold(in_dev);
1449 im->multiaddr = addr;
1450 /* initial mode is (EX, empty) */
1451 im->sfmode = mode;
1452 im->sfcount[mode] = 1;
1453 refcount_set(&im->refcnt, 1);
1454 spin_lock_init(&im->lock);
1455 #ifdef CONFIG_IP_MULTICAST
1456 timer_setup(&im->timer, igmp_timer_expire, 0);
1457 #endif
1458
1459 im->next_rcu = in_dev->mc_list;
1460 in_dev->mc_count++;
1461 rcu_assign_pointer(in_dev->mc_list, im);
1462
1463 ip_mc_hash_add(in_dev, im);
1464
1465 #ifdef CONFIG_IP_MULTICAST
1466 igmpv3_del_delrec(in_dev, im);
1467 #endif
1468 igmp_group_added(im);
1469 if (!in_dev->dead)
1470 ip_rt_multicast_event(in_dev);
1471 out:
1472 return;
1473 }
1474
1475 void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1476 {
1477 ____ip_mc_inc_group(in_dev, addr, MCAST_EXCLUDE, gfp);
1478 }
1479 EXPORT_SYMBOL(__ip_mc_inc_group);
1480
1481 void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
1482 {
1483 __ip_mc_inc_group(in_dev, addr, GFP_KERNEL);
1484 }
1485 EXPORT_SYMBOL(ip_mc_inc_group);
1486
1487 static int ip_mc_check_iphdr(struct sk_buff *skb)
1488 {
1489 const struct iphdr *iph;
1490 unsigned int len;
1491 unsigned int offset = skb_network_offset(skb) + sizeof(*iph);
1492
1493 if (!pskb_may_pull(skb, offset))
1494 return -EINVAL;
1495
1496 iph = ip_hdr(skb);
1497
1498 if (iph->version != 4 || ip_hdrlen(skb) < sizeof(*iph))
1499 return -EINVAL;
1500
1501 offset += ip_hdrlen(skb) - sizeof(*iph);
1502
1503 if (!pskb_may_pull(skb, offset))
1504 return -EINVAL;
1505
1506 iph = ip_hdr(skb);
1507
1508 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1509 return -EINVAL;
1510
1511 len = skb_network_offset(skb) + ntohs(iph->tot_len);
1512 if (skb->len < len || len < offset)
1513 return -EINVAL;
1514
1515 skb_set_transport_header(skb, offset);
1516
1517 return 0;
1518 }
1519
1520 static int ip_mc_check_igmp_reportv3(struct sk_buff *skb)
1521 {
1522 unsigned int len = skb_transport_offset(skb);
1523
1524 len += sizeof(struct igmpv3_report);
1525
1526 return ip_mc_may_pull(skb, len) ? 0 : -EINVAL;
1527 }
1528
1529 static int ip_mc_check_igmp_query(struct sk_buff *skb)
1530 {
1531 unsigned int transport_len = ip_transport_len(skb);
1532 unsigned int len;
1533
1534 /* IGMPv{1,2}? */
1535 if (transport_len != sizeof(struct igmphdr)) {
1536 /* or IGMPv3? */
1537 if (transport_len < sizeof(struct igmpv3_query))
1538 return -EINVAL;
1539
1540 len = skb_transport_offset(skb) + sizeof(struct igmpv3_query);
1541 if (!ip_mc_may_pull(skb, len))
1542 return -EINVAL;
1543 }
1544
1545 /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1546 * all-systems destination addresses (224.0.0.1) for general queries
1547 */
1548 if (!igmp_hdr(skb)->group &&
1549 ip_hdr(skb)->daddr != htonl(INADDR_ALLHOSTS_GROUP))
1550 return -EINVAL;
1551
1552 return 0;
1553 }
1554
1555 static int ip_mc_check_igmp_msg(struct sk_buff *skb)
1556 {
1557 switch (igmp_hdr(skb)->type) {
1558 case IGMP_HOST_LEAVE_MESSAGE:
1559 case IGMP_HOST_MEMBERSHIP_REPORT:
1560 case IGMPV2_HOST_MEMBERSHIP_REPORT:
1561 return 0;
1562 case IGMPV3_HOST_MEMBERSHIP_REPORT:
1563 return ip_mc_check_igmp_reportv3(skb);
1564 case IGMP_HOST_MEMBERSHIP_QUERY:
1565 return ip_mc_check_igmp_query(skb);
1566 default:
1567 return -ENOMSG;
1568 }
1569 }
1570
1571 static __sum16 ip_mc_validate_checksum(struct sk_buff *skb)
1572 {
1573 return skb_checksum_simple_validate(skb);
1574 }
1575
1576 static int ip_mc_check_igmp_csum(struct sk_buff *skb)
1577 {
1578 unsigned int len = skb_transport_offset(skb) + sizeof(struct igmphdr);
1579 unsigned int transport_len = ip_transport_len(skb);
1580 struct sk_buff *skb_chk;
1581
1582 if (!ip_mc_may_pull(skb, len))
1583 return -EINVAL;
1584
1585 skb_chk = skb_checksum_trimmed(skb, transport_len,
1586 ip_mc_validate_checksum);
1587 if (!skb_chk)
1588 return -EINVAL;
1589
1590 if (skb_chk != skb)
1591 kfree_skb(skb_chk);
1592
1593 return 0;
1594 }
1595
1596 /**
1597 * ip_mc_check_igmp - checks whether this is a sane IGMP packet
1598 * @skb: the skb to validate
1599 *
1600 * Checks whether an IPv4 packet is a valid IGMP packet. If so sets
1601 * skb transport header accordingly and returns zero.
1602 *
1603 * -EINVAL: A broken packet was detected, i.e. it violates some internet
1604 * standard
1605 * -ENOMSG: IP header validation succeeded but it is not an IGMP packet.
1606 * -ENOMEM: A memory allocation failure happened.
1607 *
1608 * Caller needs to set the skb network header and free any returned skb if it
1609 * differs from the provided skb.
1610 */
1611 int ip_mc_check_igmp(struct sk_buff *skb)
1612 {
1613 int ret = ip_mc_check_iphdr(skb);
1614
1615 if (ret < 0)
1616 return ret;
1617
1618 if (ip_hdr(skb)->protocol != IPPROTO_IGMP)
1619 return -ENOMSG;
1620
1621 ret = ip_mc_check_igmp_csum(skb);
1622 if (ret < 0)
1623 return ret;
1624
1625 return ip_mc_check_igmp_msg(skb);
1626 }
1627 EXPORT_SYMBOL(ip_mc_check_igmp);
1628
1629 /*
1630 * Resend IGMP JOIN report; used by netdev notifier.
1631 */
1632 static void ip_mc_rejoin_groups(struct in_device *in_dev)
1633 {
1634 #ifdef CONFIG_IP_MULTICAST
1635 struct ip_mc_list *im;
1636 int type;
1637 struct net *net = dev_net(in_dev->dev);
1638
1639 ASSERT_RTNL();
1640
1641 for_each_pmc_rtnl(in_dev, im) {
1642 if (im->multiaddr == IGMP_ALL_HOSTS)
1643 continue;
1644 if (ipv4_is_local_multicast(im->multiaddr) &&
1645 !net->ipv4.sysctl_igmp_llm_reports)
1646 continue;
1647
1648 /* a failover is happening and switches
1649 * must be notified immediately
1650 */
1651 if (IGMP_V1_SEEN(in_dev))
1652 type = IGMP_HOST_MEMBERSHIP_REPORT;
1653 else if (IGMP_V2_SEEN(in_dev))
1654 type = IGMPV2_HOST_MEMBERSHIP_REPORT;
1655 else
1656 type = IGMPV3_HOST_MEMBERSHIP_REPORT;
1657 igmp_send_report(in_dev, im, type);
1658 }
1659 #endif
1660 }
1661
1662 /*
1663 * A socket has left a multicast group on device dev
1664 */
1665
1666 void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp)
1667 {
1668 struct ip_mc_list *i;
1669 struct ip_mc_list __rcu **ip;
1670
1671 ASSERT_RTNL();
1672
1673 for (ip = &in_dev->mc_list;
1674 (i = rtnl_dereference(*ip)) != NULL;
1675 ip = &i->next_rcu) {
1676 if (i->multiaddr == addr) {
1677 if (--i->users == 0) {
1678 ip_mc_hash_remove(in_dev, i);
1679 *ip = i->next_rcu;
1680 in_dev->mc_count--;
1681 __igmp_group_dropped(i, gfp);
1682 ip_mc_clear_src(i);
1683
1684 if (!in_dev->dead)
1685 ip_rt_multicast_event(in_dev);
1686
1687 ip_ma_put(i);
1688 return;
1689 }
1690 break;
1691 }
1692 }
1693 }
1694 EXPORT_SYMBOL(__ip_mc_dec_group);
1695
1696 /* Device changing type */
1697
1698 void ip_mc_unmap(struct in_device *in_dev)
1699 {
1700 struct ip_mc_list *pmc;
1701
1702 ASSERT_RTNL();
1703
1704 for_each_pmc_rtnl(in_dev, pmc)
1705 igmp_group_dropped(pmc);
1706 }
1707
1708 void ip_mc_remap(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 #ifdef CONFIG_IP_MULTICAST
1716 igmpv3_del_delrec(in_dev, pmc);
1717 #endif
1718 igmp_group_added(pmc);
1719 }
1720 }
1721
1722 /* Device going down */
1723
1724 void ip_mc_down(struct in_device *in_dev)
1725 {
1726 struct ip_mc_list *pmc;
1727
1728 ASSERT_RTNL();
1729
1730 for_each_pmc_rtnl(in_dev, pmc)
1731 igmp_group_dropped(pmc);
1732
1733 #ifdef CONFIG_IP_MULTICAST
1734 WRITE_ONCE(in_dev->mr_ifc_count, 0);
1735 if (del_timer(&in_dev->mr_ifc_timer))
1736 __in_dev_put(in_dev);
1737 in_dev->mr_gq_running = 0;
1738 if (del_timer(&in_dev->mr_gq_timer))
1739 __in_dev_put(in_dev);
1740 #endif
1741
1742 ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
1743 }
1744
1745 #ifdef CONFIG_IP_MULTICAST
1746 static void ip_mc_reset(struct in_device *in_dev)
1747 {
1748 struct net *net = dev_net(in_dev->dev);
1749
1750 in_dev->mr_qi = IGMP_QUERY_INTERVAL;
1751 in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
1752 in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
1753 }
1754 #else
1755 static void ip_mc_reset(struct in_device *in_dev)
1756 {
1757 }
1758 #endif
1759
1760 void ip_mc_init_dev(struct in_device *in_dev)
1761 {
1762 ASSERT_RTNL();
1763
1764 #ifdef CONFIG_IP_MULTICAST
1765 timer_setup(&in_dev->mr_gq_timer, igmp_gq_timer_expire, 0);
1766 timer_setup(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire, 0);
1767 #endif
1768 ip_mc_reset(in_dev);
1769
1770 spin_lock_init(&in_dev->mc_tomb_lock);
1771 }
1772
1773 /* Device going up */
1774
1775 void ip_mc_up(struct in_device *in_dev)
1776 {
1777 struct ip_mc_list *pmc;
1778
1779 ASSERT_RTNL();
1780
1781 ip_mc_reset(in_dev);
1782 ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
1783
1784 for_each_pmc_rtnl(in_dev, pmc) {
1785 #ifdef CONFIG_IP_MULTICAST
1786 igmpv3_del_delrec(in_dev, pmc);
1787 #endif
1788 igmp_group_added(pmc);
1789 }
1790 }
1791
1792 /*
1793 * Device is about to be destroyed: clean up.
1794 */
1795
1796 void ip_mc_destroy_dev(struct in_device *in_dev)
1797 {
1798 struct ip_mc_list *i;
1799
1800 ASSERT_RTNL();
1801
1802 /* Deactivate timers */
1803 ip_mc_down(in_dev);
1804 #ifdef CONFIG_IP_MULTICAST
1805 igmpv3_clear_delrec(in_dev);
1806 #endif
1807
1808 while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
1809 in_dev->mc_list = i->next_rcu;
1810 in_dev->mc_count--;
1811 ip_mc_clear_src(i);
1812 ip_ma_put(i);
1813 }
1814 }
1815
1816 /* RTNL is locked */
1817 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
1818 {
1819 struct net_device *dev = NULL;
1820 struct in_device *idev = NULL;
1821
1822 if (imr->imr_ifindex) {
1823 idev = inetdev_by_index(net, imr->imr_ifindex);
1824 return idev;
1825 }
1826 if (imr->imr_address.s_addr) {
1827 dev = __ip_dev_find(net, imr->imr_address.s_addr, false);
1828 if (!dev)
1829 return NULL;
1830 }
1831
1832 if (!dev) {
1833 struct rtable *rt = ip_route_output(net,
1834 imr->imr_multiaddr.s_addr,
1835 0, 0, 0);
1836 if (!IS_ERR(rt)) {
1837 dev = rt->dst.dev;
1838 ip_rt_put(rt);
1839 }
1840 }
1841 if (dev) {
1842 imr->imr_ifindex = dev->ifindex;
1843 idev = __in_dev_get_rtnl(dev);
1844 }
1845 return idev;
1846 }
1847
1848 /*
1849 * Join a socket to a group
1850 */
1851
1852 static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
1853 __be32 *psfsrc)
1854 {
1855 struct ip_sf_list *psf, *psf_prev;
1856 int rv = 0;
1857
1858 psf_prev = NULL;
1859 for (psf = pmc->sources; psf; psf = psf->sf_next) {
1860 if (psf->sf_inaddr == *psfsrc)
1861 break;
1862 psf_prev = psf;
1863 }
1864 if (!psf || psf->sf_count[sfmode] == 0) {
1865 /* source filter not found, or count wrong => bug */
1866 return -ESRCH;
1867 }
1868 psf->sf_count[sfmode]--;
1869 if (psf->sf_count[sfmode] == 0) {
1870 ip_rt_multicast_event(pmc->interface);
1871 }
1872 if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1873 #ifdef CONFIG_IP_MULTICAST
1874 struct in_device *in_dev = pmc->interface;
1875 struct net *net = dev_net(in_dev->dev);
1876 #endif
1877
1878 /* no more filters for this source */
1879 if (psf_prev)
1880 psf_prev->sf_next = psf->sf_next;
1881 else
1882 pmc->sources = psf->sf_next;
1883 #ifdef CONFIG_IP_MULTICAST
1884 if (psf->sf_oldin &&
1885 !IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
1886 psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1887 psf->sf_next = pmc->tomb;
1888 pmc->tomb = psf;
1889 rv = 1;
1890 } else
1891 #endif
1892 kfree(psf);
1893 }
1894 return rv;
1895 }
1896
1897 #ifndef CONFIG_IP_MULTICAST
1898 #define igmp_ifc_event(x) do { } while (0)
1899 #endif
1900
1901 static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
1902 int sfcount, __be32 *psfsrc, int delta)
1903 {
1904 struct ip_mc_list *pmc;
1905 int changerec = 0;
1906 int i, err;
1907
1908 if (!in_dev)
1909 return -ENODEV;
1910 rcu_read_lock();
1911 for_each_pmc_rcu(in_dev, pmc) {
1912 if (*pmca == pmc->multiaddr)
1913 break;
1914 }
1915 if (!pmc) {
1916 /* MCA not found?? bug */
1917 rcu_read_unlock();
1918 return -ESRCH;
1919 }
1920 spin_lock_bh(&pmc->lock);
1921 rcu_read_unlock();
1922 #ifdef CONFIG_IP_MULTICAST
1923 sf_markstate(pmc);
1924 #endif
1925 if (!delta) {
1926 err = -EINVAL;
1927 if (!pmc->sfcount[sfmode])
1928 goto out_unlock;
1929 pmc->sfcount[sfmode]--;
1930 }
1931 err = 0;
1932 for (i = 0; i < sfcount; i++) {
1933 int rv = ip_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1934
1935 changerec |= rv > 0;
1936 if (!err && rv < 0)
1937 err = rv;
1938 }
1939 if (pmc->sfmode == MCAST_EXCLUDE &&
1940 pmc->sfcount[MCAST_EXCLUDE] == 0 &&
1941 pmc->sfcount[MCAST_INCLUDE]) {
1942 #ifdef CONFIG_IP_MULTICAST
1943 struct ip_sf_list *psf;
1944 struct net *net = dev_net(in_dev->dev);
1945 #endif
1946
1947 /* filter mode change */
1948 pmc->sfmode = MCAST_INCLUDE;
1949 #ifdef CONFIG_IP_MULTICAST
1950 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
1951 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
1952 for (psf = pmc->sources; psf; psf = psf->sf_next)
1953 psf->sf_crcount = 0;
1954 igmp_ifc_event(pmc->interface);
1955 } else if (sf_setstate(pmc) || changerec) {
1956 igmp_ifc_event(pmc->interface);
1957 #endif
1958 }
1959 out_unlock:
1960 spin_unlock_bh(&pmc->lock);
1961 return err;
1962 }
1963
1964 /*
1965 * Add multicast single-source filter to the interface list
1966 */
1967 static int ip_mc_add1_src(struct ip_mc_list *pmc, int sfmode,
1968 __be32 *psfsrc)
1969 {
1970 struct ip_sf_list *psf, *psf_prev;
1971
1972 psf_prev = NULL;
1973 for (psf = pmc->sources; psf; psf = psf->sf_next) {
1974 if (psf->sf_inaddr == *psfsrc)
1975 break;
1976 psf_prev = psf;
1977 }
1978 if (!psf) {
1979 psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1980 if (!psf)
1981 return -ENOBUFS;
1982 psf->sf_inaddr = *psfsrc;
1983 if (psf_prev) {
1984 psf_prev->sf_next = psf;
1985 } else
1986 pmc->sources = psf;
1987 }
1988 psf->sf_count[sfmode]++;
1989 if (psf->sf_count[sfmode] == 1) {
1990 ip_rt_multicast_event(pmc->interface);
1991 }
1992 return 0;
1993 }
1994
1995 #ifdef CONFIG_IP_MULTICAST
1996 static void sf_markstate(struct ip_mc_list *pmc)
1997 {
1998 struct ip_sf_list *psf;
1999 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2000
2001 for (psf = pmc->sources; psf; psf = psf->sf_next)
2002 if (pmc->sfcount[MCAST_EXCLUDE]) {
2003 psf->sf_oldin = mca_xcount ==
2004 psf->sf_count[MCAST_EXCLUDE] &&
2005 !psf->sf_count[MCAST_INCLUDE];
2006 } else
2007 psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2008 }
2009
2010 static int sf_setstate(struct ip_mc_list *pmc)
2011 {
2012 struct ip_sf_list *psf, *dpsf;
2013 int mca_xcount = pmc->sfcount[MCAST_EXCLUDE];
2014 int qrv = pmc->interface->mr_qrv;
2015 int new_in, rv;
2016
2017 rv = 0;
2018 for (psf = pmc->sources; psf; psf = psf->sf_next) {
2019 if (pmc->sfcount[MCAST_EXCLUDE]) {
2020 new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2021 !psf->sf_count[MCAST_INCLUDE];
2022 } else
2023 new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2024 if (new_in) {
2025 if (!psf->sf_oldin) {
2026 struct ip_sf_list *prev = NULL;
2027
2028 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next) {
2029 if (dpsf->sf_inaddr == psf->sf_inaddr)
2030 break;
2031 prev = dpsf;
2032 }
2033 if (dpsf) {
2034 if (prev)
2035 prev->sf_next = dpsf->sf_next;
2036 else
2037 pmc->tomb = dpsf->sf_next;
2038 kfree(dpsf);
2039 }
2040 psf->sf_crcount = qrv;
2041 rv++;
2042 }
2043 } else if (psf->sf_oldin) {
2044
2045 psf->sf_crcount = 0;
2046 /*
2047 * add or update "delete" records if an active filter
2048 * is now inactive
2049 */
2050 for (dpsf = pmc->tomb; dpsf; dpsf = dpsf->sf_next)
2051 if (dpsf->sf_inaddr == psf->sf_inaddr)
2052 break;
2053 if (!dpsf) {
2054 dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2055 if (!dpsf)
2056 continue;
2057 *dpsf = *psf;
2058 /* pmc->lock held by callers */
2059 dpsf->sf_next = pmc->tomb;
2060 pmc->tomb = dpsf;
2061 }
2062 dpsf->sf_crcount = qrv;
2063 rv++;
2064 }
2065 }
2066 return rv;
2067 }
2068 #endif
2069
2070 /*
2071 * Add multicast source filter list to the interface list
2072 */
2073 static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
2074 int sfcount, __be32 *psfsrc, int delta)
2075 {
2076 struct ip_mc_list *pmc;
2077 int isexclude;
2078 int i, err;
2079
2080 if (!in_dev)
2081 return -ENODEV;
2082 rcu_read_lock();
2083 for_each_pmc_rcu(in_dev, pmc) {
2084 if (*pmca == pmc->multiaddr)
2085 break;
2086 }
2087 if (!pmc) {
2088 /* MCA not found?? bug */
2089 rcu_read_unlock();
2090 return -ESRCH;
2091 }
2092 spin_lock_bh(&pmc->lock);
2093 rcu_read_unlock();
2094
2095 #ifdef CONFIG_IP_MULTICAST
2096 sf_markstate(pmc);
2097 #endif
2098 isexclude = pmc->sfmode == MCAST_EXCLUDE;
2099 if (!delta)
2100 pmc->sfcount[sfmode]++;
2101 err = 0;
2102 for (i = 0; i < sfcount; i++) {
2103 err = ip_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2104 if (err)
2105 break;
2106 }
2107 if (err) {
2108 int j;
2109
2110 if (!delta)
2111 pmc->sfcount[sfmode]--;
2112 for (j = 0; j < i; j++)
2113 (void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2114 } else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {
2115 #ifdef CONFIG_IP_MULTICAST
2116 struct ip_sf_list *psf;
2117 struct net *net = dev_net(pmc->interface->dev);
2118 in_dev = pmc->interface;
2119 #endif
2120
2121 /* filter mode change */
2122 if (pmc->sfcount[MCAST_EXCLUDE])
2123 pmc->sfmode = MCAST_EXCLUDE;
2124 else if (pmc->sfcount[MCAST_INCLUDE])
2125 pmc->sfmode = MCAST_INCLUDE;
2126 #ifdef CONFIG_IP_MULTICAST
2127 /* else no filters; keep old mode for reports */
2128
2129 pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
2130 WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
2131 for (psf = pmc->sources; psf; psf = psf->sf_next)
2132 psf->sf_crcount = 0;
2133 igmp_ifc_event(in_dev);
2134 } else if (sf_setstate(pmc)) {
2135 igmp_ifc_event(in_dev);
2136 #endif
2137 }
2138 spin_unlock_bh(&pmc->lock);
2139 return err;
2140 }
2141
2142 static void ip_mc_clear_src(struct ip_mc_list *pmc)
2143 {
2144 struct ip_sf_list *tomb, *sources;
2145
2146 spin_lock_bh(&pmc->lock);
2147 tomb = pmc->tomb;
2148 pmc->tomb = NULL;
2149 sources = pmc->sources;
2150 pmc->sources = NULL;
2151 pmc->sfmode = MCAST_EXCLUDE;
2152 pmc->sfcount[MCAST_INCLUDE] = 0;
2153 pmc->sfcount[MCAST_EXCLUDE] = 1;
2154 spin_unlock_bh(&pmc->lock);
2155
2156 ip_sf_list_clear_all(tomb);
2157 ip_sf_list_clear_all(sources);
2158 }
2159
2160 /* Join a multicast group
2161 */
2162 static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
2163 unsigned int mode)
2164 {
2165 __be32 addr = imr->imr_multiaddr.s_addr;
2166 struct ip_mc_socklist *iml, *i;
2167 struct in_device *in_dev;
2168 struct inet_sock *inet = inet_sk(sk);
2169 struct net *net = sock_net(sk);
2170 int ifindex;
2171 int count = 0;
2172 int err;
2173
2174 ASSERT_RTNL();
2175
2176 if (!ipv4_is_multicast(addr))
2177 return -EINVAL;
2178
2179 in_dev = ip_mc_find_dev(net, imr);
2180
2181 if (!in_dev) {
2182 err = -ENODEV;
2183 goto done;
2184 }
2185
2186 err = -EADDRINUSE;
2187 ifindex = imr->imr_ifindex;
2188 for_each_pmc_rtnl(inet, i) {
2189 if (i->multi.imr_multiaddr.s_addr == addr &&
2190 i->multi.imr_ifindex == ifindex)
2191 goto done;
2192 count++;
2193 }
2194 err = -ENOBUFS;
2195 if (count >= net->ipv4.sysctl_igmp_max_memberships)
2196 goto done;
2197 iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
2198 if (!iml)
2199 goto done;
2200
2201 memcpy(&iml->multi, imr, sizeof(*imr));
2202 iml->next_rcu = inet->mc_list;
2203 iml->sflist = NULL;
2204 iml->sfmode = mode;
2205 rcu_assign_pointer(inet->mc_list, iml);
2206 ____ip_mc_inc_group(in_dev, addr, mode, GFP_KERNEL);
2207 err = 0;
2208 done:
2209 return err;
2210 }
2211
2212 /* Join ASM (Any-Source Multicast) group
2213 */
2214 int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
2215 {
2216 return __ip_mc_join_group(sk, imr, MCAST_EXCLUDE);
2217 }
2218 EXPORT_SYMBOL(ip_mc_join_group);
2219
2220 /* Join SSM (Source-Specific Multicast) group
2221 */
2222 int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
2223 unsigned int mode)
2224 {
2225 return __ip_mc_join_group(sk, imr, mode);
2226 }
2227
2228 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
2229 struct in_device *in_dev)
2230 {
2231 struct ip_sf_socklist *psf = rtnl_dereference(iml->sflist);
2232 int err;
2233
2234 if (!psf) {
2235 /* any-source empty exclude case */
2236 return ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2237 iml->sfmode, 0, NULL, 0);
2238 }
2239 err = ip_mc_del_src(in_dev, &iml->multi.imr_multiaddr.s_addr,
2240 iml->sfmode, psf->sl_count, psf->sl_addr, 0);
2241 RCU_INIT_POINTER(iml->sflist, NULL);
2242 /* decrease mem now to avoid the memleak warning */
2243 atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc);
2244 kfree_rcu(psf, rcu);
2245 return err;
2246 }
2247
2248 int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
2249 {
2250 struct inet_sock *inet = inet_sk(sk);
2251 struct ip_mc_socklist *iml;
2252 struct ip_mc_socklist __rcu **imlp;
2253 struct in_device *in_dev;
2254 struct net *net = sock_net(sk);
2255 __be32 group = imr->imr_multiaddr.s_addr;
2256 u32 ifindex;
2257 int ret = -EADDRNOTAVAIL;
2258
2259 ASSERT_RTNL();
2260
2261 in_dev = ip_mc_find_dev(net, imr);
2262 if (!imr->imr_ifindex && !imr->imr_address.s_addr && !in_dev) {
2263 ret = -ENODEV;
2264 goto out;
2265 }
2266 ifindex = imr->imr_ifindex;
2267 for (imlp = &inet->mc_list;
2268 (iml = rtnl_dereference(*imlp)) != NULL;
2269 imlp = &iml->next_rcu) {
2270 if (iml->multi.imr_multiaddr.s_addr != group)
2271 continue;
2272 if (ifindex) {
2273 if (iml->multi.imr_ifindex != ifindex)
2274 continue;
2275 } else if (imr->imr_address.s_addr && imr->imr_address.s_addr !=
2276 iml->multi.imr_address.s_addr)
2277 continue;
2278
2279 (void) ip_mc_leave_src(sk, iml, in_dev);
2280
2281 *imlp = iml->next_rcu;
2282
2283 if (in_dev)
2284 ip_mc_dec_group(in_dev, group);
2285
2286 /* decrease mem now to avoid the memleak warning */
2287 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2288 kfree_rcu(iml, rcu);
2289 return 0;
2290 }
2291 out:
2292 return ret;
2293 }
2294 EXPORT_SYMBOL(ip_mc_leave_group);
2295
2296 int ip_mc_source(int add, int omode, struct sock *sk, struct
2297 ip_mreq_source *mreqs, int ifindex)
2298 {
2299 int err;
2300 struct ip_mreqn imr;
2301 __be32 addr = mreqs->imr_multiaddr;
2302 struct ip_mc_socklist *pmc;
2303 struct in_device *in_dev = NULL;
2304 struct inet_sock *inet = inet_sk(sk);
2305 struct ip_sf_socklist *psl;
2306 struct net *net = sock_net(sk);
2307 int leavegroup = 0;
2308 int i, j, rv;
2309
2310 if (!ipv4_is_multicast(addr))
2311 return -EINVAL;
2312
2313 ASSERT_RTNL();
2314
2315 imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
2316 imr.imr_address.s_addr = mreqs->imr_interface;
2317 imr.imr_ifindex = ifindex;
2318 in_dev = ip_mc_find_dev(net, &imr);
2319
2320 if (!in_dev) {
2321 err = -ENODEV;
2322 goto done;
2323 }
2324 err = -EADDRNOTAVAIL;
2325
2326 for_each_pmc_rtnl(inet, pmc) {
2327 if ((pmc->multi.imr_multiaddr.s_addr ==
2328 imr.imr_multiaddr.s_addr) &&
2329 (pmc->multi.imr_ifindex == imr.imr_ifindex))
2330 break;
2331 }
2332 if (!pmc) { /* must have a prior join */
2333 err = -EINVAL;
2334 goto done;
2335 }
2336 /* if a source filter was set, must be the same mode as before */
2337 if (pmc->sflist) {
2338 if (pmc->sfmode != omode) {
2339 err = -EINVAL;
2340 goto done;
2341 }
2342 } else if (pmc->sfmode != omode) {
2343 /* allow mode switches for empty-set filters */
2344 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 0, NULL, 0);
2345 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, pmc->sfmode, 0,
2346 NULL, 0);
2347 pmc->sfmode = omode;
2348 }
2349
2350 psl = rtnl_dereference(pmc->sflist);
2351 if (!add) {
2352 if (!psl)
2353 goto done; /* err = -EADDRNOTAVAIL */
2354 rv = !0;
2355 for (i = 0; i < psl->sl_count; i++) {
2356 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2357 sizeof(__be32));
2358 if (rv == 0)
2359 break;
2360 }
2361 if (rv) /* source not found */
2362 goto done; /* err = -EADDRNOTAVAIL */
2363
2364 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2365 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
2366 leavegroup = 1;
2367 goto done;
2368 }
2369
2370 /* update the interface filter */
2371 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2372 &mreqs->imr_sourceaddr, 1);
2373
2374 for (j = i+1; j < psl->sl_count; j++)
2375 psl->sl_addr[j-1] = psl->sl_addr[j];
2376 psl->sl_count--;
2377 err = 0;
2378 goto done;
2379 }
2380 /* else, add a new source to the filter */
2381
2382 if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
2383 err = -ENOBUFS;
2384 goto done;
2385 }
2386 if (!psl || psl->sl_count == psl->sl_max) {
2387 struct ip_sf_socklist *newpsl;
2388 int count = IP_SFBLOCK;
2389
2390 if (psl)
2391 count += psl->sl_max;
2392 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count),
2393 GFP_KERNEL);
2394 if (!newpsl) {
2395 err = -ENOBUFS;
2396 goto done;
2397 }
2398 newpsl->sl_max = count;
2399 newpsl->sl_count = count - IP_SFBLOCK;
2400 if (psl) {
2401 for (i = 0; i < psl->sl_count; i++)
2402 newpsl->sl_addr[i] = psl->sl_addr[i];
2403 /* decrease mem now to avoid the memleak warning */
2404 atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2405 &sk->sk_omem_alloc);
2406 kfree_rcu(psl, rcu);
2407 }
2408 rcu_assign_pointer(pmc->sflist, newpsl);
2409 psl = newpsl;
2410 }
2411 rv = 1; /* > 0 for insert logic below if sl_count is 0 */
2412 for (i = 0; i < psl->sl_count; i++) {
2413 rv = memcmp(&psl->sl_addr[i], &mreqs->imr_sourceaddr,
2414 sizeof(__be32));
2415 if (rv == 0)
2416 break;
2417 }
2418 if (rv == 0) /* address already there is an error */
2419 goto done;
2420 for (j = psl->sl_count-1; j >= i; j--)
2421 psl->sl_addr[j+1] = psl->sl_addr[j];
2422 psl->sl_addr[i] = mreqs->imr_sourceaddr;
2423 psl->sl_count++;
2424 err = 0;
2425 /* update the interface list */
2426 ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
2427 &mreqs->imr_sourceaddr, 1);
2428 done:
2429 if (leavegroup)
2430 err = ip_mc_leave_group(sk, &imr);
2431 return err;
2432 }
2433
2434 int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
2435 {
2436 int err = 0;
2437 struct ip_mreqn imr;
2438 __be32 addr = msf->imsf_multiaddr;
2439 struct ip_mc_socklist *pmc;
2440 struct in_device *in_dev;
2441 struct inet_sock *inet = inet_sk(sk);
2442 struct ip_sf_socklist *newpsl, *psl;
2443 struct net *net = sock_net(sk);
2444 int leavegroup = 0;
2445
2446 if (!ipv4_is_multicast(addr))
2447 return -EINVAL;
2448 if (msf->imsf_fmode != MCAST_INCLUDE &&
2449 msf->imsf_fmode != MCAST_EXCLUDE)
2450 return -EINVAL;
2451
2452 ASSERT_RTNL();
2453
2454 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2455 imr.imr_address.s_addr = msf->imsf_interface;
2456 imr.imr_ifindex = ifindex;
2457 in_dev = ip_mc_find_dev(net, &imr);
2458
2459 if (!in_dev) {
2460 err = -ENODEV;
2461 goto done;
2462 }
2463
2464 /* special case - (INCLUDE, empty) == LEAVE_GROUP */
2465 if (msf->imsf_fmode == MCAST_INCLUDE && msf->imsf_numsrc == 0) {
2466 leavegroup = 1;
2467 goto done;
2468 }
2469
2470 for_each_pmc_rtnl(inet, pmc) {
2471 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2472 pmc->multi.imr_ifindex == imr.imr_ifindex)
2473 break;
2474 }
2475 if (!pmc) { /* must have a prior join */
2476 err = -EINVAL;
2477 goto done;
2478 }
2479 if (msf->imsf_numsrc) {
2480 newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr,
2481 msf->imsf_numsrc),
2482 GFP_KERNEL);
2483 if (!newpsl) {
2484 err = -ENOBUFS;
2485 goto done;
2486 }
2487 newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
2488 memcpy(newpsl->sl_addr, msf->imsf_slist_flex,
2489 flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc));
2490 err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2491 msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
2492 if (err) {
2493 sock_kfree_s(sk, newpsl,
2494 struct_size(newpsl, sl_addr,
2495 newpsl->sl_max));
2496 goto done;
2497 }
2498 } else {
2499 newpsl = NULL;
2500 (void) ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
2501 msf->imsf_fmode, 0, NULL, 0);
2502 }
2503 psl = rtnl_dereference(pmc->sflist);
2504 if (psl) {
2505 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2506 psl->sl_count, psl->sl_addr, 0);
2507 /* decrease mem now to avoid the memleak warning */
2508 atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2509 &sk->sk_omem_alloc);
2510 kfree_rcu(psl, rcu);
2511 } else
2512 (void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
2513 0, NULL, 0);
2514 rcu_assign_pointer(pmc->sflist, newpsl);
2515 pmc->sfmode = msf->imsf_fmode;
2516 err = 0;
2517 done:
2518 if (leavegroup)
2519 err = ip_mc_leave_group(sk, &imr);
2520 return err;
2521 }
2522
2523 int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
2524 struct ip_msfilter __user *optval, int __user *optlen)
2525 {
2526 int err, len, count, copycount;
2527 struct ip_mreqn imr;
2528 __be32 addr = msf->imsf_multiaddr;
2529 struct ip_mc_socklist *pmc;
2530 struct in_device *in_dev;
2531 struct inet_sock *inet = inet_sk(sk);
2532 struct ip_sf_socklist *psl;
2533 struct net *net = sock_net(sk);
2534
2535 ASSERT_RTNL();
2536
2537 if (!ipv4_is_multicast(addr))
2538 return -EINVAL;
2539
2540 imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
2541 imr.imr_address.s_addr = msf->imsf_interface;
2542 imr.imr_ifindex = 0;
2543 in_dev = ip_mc_find_dev(net, &imr);
2544
2545 if (!in_dev) {
2546 err = -ENODEV;
2547 goto done;
2548 }
2549 err = -EADDRNOTAVAIL;
2550
2551 for_each_pmc_rtnl(inet, pmc) {
2552 if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
2553 pmc->multi.imr_ifindex == imr.imr_ifindex)
2554 break;
2555 }
2556 if (!pmc) /* must have a prior join */
2557 goto done;
2558 msf->imsf_fmode = pmc->sfmode;
2559 psl = rtnl_dereference(pmc->sflist);
2560 if (!psl) {
2561 len = 0;
2562 count = 0;
2563 } else {
2564 count = psl->sl_count;
2565 }
2566 copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
2567 len = flex_array_size(psl, sl_addr, copycount);
2568 msf->imsf_numsrc = count;
2569 if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
2570 copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
2571 return -EFAULT;
2572 }
2573 if (len &&
2574 copy_to_user(&optval->imsf_slist_flex[0], psl->sl_addr, len))
2575 return -EFAULT;
2576 return 0;
2577 done:
2578 return err;
2579 }
2580
2581 int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
2582 struct sockaddr_storage __user *p)
2583 {
2584 int i, count, copycount;
2585 struct sockaddr_in *psin;
2586 __be32 addr;
2587 struct ip_mc_socklist *pmc;
2588 struct inet_sock *inet = inet_sk(sk);
2589 struct ip_sf_socklist *psl;
2590
2591 ASSERT_RTNL();
2592
2593 psin = (struct sockaddr_in *)&gsf->gf_group;
2594 if (psin->sin_family != AF_INET)
2595 return -EINVAL;
2596 addr = psin->sin_addr.s_addr;
2597 if (!ipv4_is_multicast(addr))
2598 return -EINVAL;
2599
2600 for_each_pmc_rtnl(inet, pmc) {
2601 if (pmc->multi.imr_multiaddr.s_addr == addr &&
2602 pmc->multi.imr_ifindex == gsf->gf_interface)
2603 break;
2604 }
2605 if (!pmc) /* must have a prior join */
2606 return -EADDRNOTAVAIL;
2607 gsf->gf_fmode = pmc->sfmode;
2608 psl = rtnl_dereference(pmc->sflist);
2609 count = psl ? psl->sl_count : 0;
2610 copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
2611 gsf->gf_numsrc = count;
2612 for (i = 0; i < copycount; i++, p++) {
2613 struct sockaddr_storage ss;
2614
2615 psin = (struct sockaddr_in *)&ss;
2616 memset(&ss, 0, sizeof(ss));
2617 psin->sin_family = AF_INET;
2618 psin->sin_addr.s_addr = psl->sl_addr[i];
2619 if (copy_to_user(p, &ss, sizeof(ss)))
2620 return -EFAULT;
2621 }
2622 return 0;
2623 }
2624
2625 /*
2626 * check if a multicast source filter allows delivery for a given <src,dst,intf>
2627 */
2628 int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr,
2629 int dif, int sdif)
2630 {
2631 struct inet_sock *inet = inet_sk(sk);
2632 struct ip_mc_socklist *pmc;
2633 struct ip_sf_socklist *psl;
2634 int i;
2635 int ret;
2636
2637 ret = 1;
2638 if (!ipv4_is_multicast(loc_addr))
2639 goto out;
2640
2641 rcu_read_lock();
2642 for_each_pmc_rcu(inet, pmc) {
2643 if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
2644 (pmc->multi.imr_ifindex == dif ||
2645 (sdif && pmc->multi.imr_ifindex == sdif)))
2646 break;
2647 }
2648 ret = inet->mc_all;
2649 if (!pmc)
2650 goto unlock;
2651 psl = rcu_dereference(pmc->sflist);
2652 ret = (pmc->sfmode == MCAST_EXCLUDE);
2653 if (!psl)
2654 goto unlock;
2655
2656 for (i = 0; i < psl->sl_count; i++) {
2657 if (psl->sl_addr[i] == rmt_addr)
2658 break;
2659 }
2660 ret = 0;
2661 if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
2662 goto unlock;
2663 if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
2664 goto unlock;
2665 ret = 1;
2666 unlock:
2667 rcu_read_unlock();
2668 out:
2669 return ret;
2670 }
2671
2672 /*
2673 * A socket is closing.
2674 */
2675
2676 void ip_mc_drop_socket(struct sock *sk)
2677 {
2678 struct inet_sock *inet = inet_sk(sk);
2679 struct ip_mc_socklist *iml;
2680 struct net *net = sock_net(sk);
2681
2682 if (!inet->mc_list)
2683 return;
2684
2685 rtnl_lock();
2686 while ((iml = rtnl_dereference(inet->mc_list)) != NULL) {
2687 struct in_device *in_dev;
2688
2689 inet->mc_list = iml->next_rcu;
2690 in_dev = inetdev_by_index(net, iml->multi.imr_ifindex);
2691 (void) ip_mc_leave_src(sk, iml, in_dev);
2692 if (in_dev)
2693 ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
2694 /* decrease mem now to avoid the memleak warning */
2695 atomic_sub(sizeof(*iml), &sk->sk_omem_alloc);
2696 kfree_rcu(iml, rcu);
2697 }
2698 rtnl_unlock();
2699 }
2700
2701 /* called with rcu_read_lock() */
2702 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u8 proto)
2703 {
2704 struct ip_mc_list *im;
2705 struct ip_mc_list __rcu **mc_hash;
2706 struct ip_sf_list *psf;
2707 int rv = 0;
2708
2709 mc_hash = rcu_dereference(in_dev->mc_hash);
2710 if (mc_hash) {
2711 u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
2712
2713 for (im = rcu_dereference(mc_hash[hash]);
2714 im != NULL;
2715 im = rcu_dereference(im->next_hash)) {
2716 if (im->multiaddr == mc_addr)
2717 break;
2718 }
2719 } else {
2720 for_each_pmc_rcu(in_dev, im) {
2721 if (im->multiaddr == mc_addr)
2722 break;
2723 }
2724 }
2725 if (im && proto == IPPROTO_IGMP) {
2726 rv = 1;
2727 } else if (im) {
2728 if (src_addr) {
2729 spin_lock_bh(&im->lock);
2730 for (psf = im->sources; psf; psf = psf->sf_next) {
2731 if (psf->sf_inaddr == src_addr)
2732 break;
2733 }
2734 if (psf)
2735 rv = psf->sf_count[MCAST_INCLUDE] ||
2736 psf->sf_count[MCAST_EXCLUDE] !=
2737 im->sfcount[MCAST_EXCLUDE];
2738 else
2739 rv = im->sfcount[MCAST_EXCLUDE] != 0;
2740 spin_unlock_bh(&im->lock);
2741 } else
2742 rv = 1; /* unspecified source; tentatively allow */
2743 }
2744 return rv;
2745 }
2746
2747 #if defined(CONFIG_PROC_FS)
2748 struct igmp_mc_iter_state {
2749 struct seq_net_private p;
2750 struct net_device *dev;
2751 struct in_device *in_dev;
2752 };
2753
2754 #define igmp_mc_seq_private(seq) ((struct igmp_mc_iter_state *)(seq)->private)
2755
2756 static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
2757 {
2758 struct net *net = seq_file_net(seq);
2759 struct ip_mc_list *im = NULL;
2760 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2761
2762 state->in_dev = NULL;
2763 for_each_netdev_rcu(net, state->dev) {
2764 struct in_device *in_dev;
2765
2766 in_dev = __in_dev_get_rcu(state->dev);
2767 if (!in_dev)
2768 continue;
2769 im = rcu_dereference(in_dev->mc_list);
2770 if (im) {
2771 state->in_dev = in_dev;
2772 break;
2773 }
2774 }
2775 return im;
2776 }
2777
2778 static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
2779 {
2780 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2781
2782 im = rcu_dereference(im->next_rcu);
2783 while (!im) {
2784 state->dev = next_net_device_rcu(state->dev);
2785 if (!state->dev) {
2786 state->in_dev = NULL;
2787 break;
2788 }
2789 state->in_dev = __in_dev_get_rcu(state->dev);
2790 if (!state->in_dev)
2791 continue;
2792 im = rcu_dereference(state->in_dev->mc_list);
2793 }
2794 return im;
2795 }
2796
2797 static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
2798 {
2799 struct ip_mc_list *im = igmp_mc_get_first(seq);
2800 if (im)
2801 while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
2802 --pos;
2803 return pos ? NULL : im;
2804 }
2805
2806 static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
2807 __acquires(rcu)
2808 {
2809 rcu_read_lock();
2810 return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2811 }
2812
2813 static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2814 {
2815 struct ip_mc_list *im;
2816 if (v == SEQ_START_TOKEN)
2817 im = igmp_mc_get_first(seq);
2818 else
2819 im = igmp_mc_get_next(seq, v);
2820 ++*pos;
2821 return im;
2822 }
2823
2824 static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
2825 __releases(rcu)
2826 {
2827 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2828
2829 state->in_dev = NULL;
2830 state->dev = NULL;
2831 rcu_read_unlock();
2832 }
2833
2834 static int igmp_mc_seq_show(struct seq_file *seq, void *v)
2835 {
2836 if (v == SEQ_START_TOKEN)
2837 seq_puts(seq,
2838 "Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n");
2839 else {
2840 struct ip_mc_list *im = (struct ip_mc_list *)v;
2841 struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
2842 char *querier;
2843 long delta;
2844
2845 #ifdef CONFIG_IP_MULTICAST
2846 querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
2847 IGMP_V2_SEEN(state->in_dev) ? "V2" :
2848 "V3";
2849 #else
2850 querier = "NONE";
2851 #endif
2852
2853 if (rcu_access_pointer(state->in_dev->mc_list) == im) {
2854 seq_printf(seq, "%d\t%-10s: %5d %7s\n",
2855 state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
2856 }
2857
2858 delta = im->timer.expires - jiffies;
2859 seq_printf(seq,
2860 "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
2861 im->multiaddr, im->users,
2862 im->tm_running,
2863 im->tm_running ? jiffies_delta_to_clock_t(delta) : 0,
2864 im->reporter);
2865 }
2866 return 0;
2867 }
2868
2869 static const struct seq_operations igmp_mc_seq_ops = {
2870 .start = igmp_mc_seq_start,
2871 .next = igmp_mc_seq_next,
2872 .stop = igmp_mc_seq_stop,
2873 .show = igmp_mc_seq_show,
2874 };
2875
2876 struct igmp_mcf_iter_state {
2877 struct seq_net_private p;
2878 struct net_device *dev;
2879 struct in_device *idev;
2880 struct ip_mc_list *im;
2881 };
2882
2883 #define igmp_mcf_seq_private(seq) ((struct igmp_mcf_iter_state *)(seq)->private)
2884
2885 static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
2886 {
2887 struct net *net = seq_file_net(seq);
2888 struct ip_sf_list *psf = NULL;
2889 struct ip_mc_list *im = NULL;
2890 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2891
2892 state->idev = NULL;
2893 state->im = NULL;
2894 for_each_netdev_rcu(net, state->dev) {
2895 struct in_device *idev;
2896 idev = __in_dev_get_rcu(state->dev);
2897 if (unlikely(!idev))
2898 continue;
2899 im = rcu_dereference(idev->mc_list);
2900 if (likely(im)) {
2901 spin_lock_bh(&im->lock);
2902 psf = im->sources;
2903 if (likely(psf)) {
2904 state->im = im;
2905 state->idev = idev;
2906 break;
2907 }
2908 spin_unlock_bh(&im->lock);
2909 }
2910 }
2911 return psf;
2912 }
2913
2914 static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
2915 {
2916 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2917
2918 psf = psf->sf_next;
2919 while (!psf) {
2920 spin_unlock_bh(&state->im->lock);
2921 state->im = state->im->next;
2922 while (!state->im) {
2923 state->dev = next_net_device_rcu(state->dev);
2924 if (!state->dev) {
2925 state->idev = NULL;
2926 goto out;
2927 }
2928 state->idev = __in_dev_get_rcu(state->dev);
2929 if (!state->idev)
2930 continue;
2931 state->im = rcu_dereference(state->idev->mc_list);
2932 }
2933 if (!state->im)
2934 break;
2935 spin_lock_bh(&state->im->lock);
2936 psf = state->im->sources;
2937 }
2938 out:
2939 return psf;
2940 }
2941
2942 static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
2943 {
2944 struct ip_sf_list *psf = igmp_mcf_get_first(seq);
2945 if (psf)
2946 while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
2947 --pos;
2948 return pos ? NULL : psf;
2949 }
2950
2951 static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2952 __acquires(rcu)
2953 {
2954 rcu_read_lock();
2955 return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2956 }
2957
2958 static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2959 {
2960 struct ip_sf_list *psf;
2961 if (v == SEQ_START_TOKEN)
2962 psf = igmp_mcf_get_first(seq);
2963 else
2964 psf = igmp_mcf_get_next(seq, v);
2965 ++*pos;
2966 return psf;
2967 }
2968
2969 static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
2970 __releases(rcu)
2971 {
2972 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2973 if (likely(state->im)) {
2974 spin_unlock_bh(&state->im->lock);
2975 state->im = NULL;
2976 }
2977 state->idev = NULL;
2978 state->dev = NULL;
2979 rcu_read_unlock();
2980 }
2981
2982 static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
2983 {
2984 struct ip_sf_list *psf = (struct ip_sf_list *)v;
2985 struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
2986
2987 if (v == SEQ_START_TOKEN) {
2988 seq_puts(seq, "Idx Device MCA SRC INC EXC\n");
2989 } else {
2990 seq_printf(seq,
2991 "%3d %6.6s 0x%08x "
2992 "0x%08x %6lu %6lu\n",
2993 state->dev->ifindex, state->dev->name,
2994 ntohl(state->im->multiaddr),
2995 ntohl(psf->sf_inaddr),
2996 psf->sf_count[MCAST_INCLUDE],
2997 psf->sf_count[MCAST_EXCLUDE]);
2998 }
2999 return 0;
3000 }
3001
3002 static const struct seq_operations igmp_mcf_seq_ops = {
3003 .start = igmp_mcf_seq_start,
3004 .next = igmp_mcf_seq_next,
3005 .stop = igmp_mcf_seq_stop,
3006 .show = igmp_mcf_seq_show,
3007 };
3008
3009 static int __net_init igmp_net_init(struct net *net)
3010 {
3011 struct proc_dir_entry *pde;
3012 int err;
3013
3014 pde = proc_create_net("igmp", 0444, net->proc_net, &igmp_mc_seq_ops,
3015 sizeof(struct igmp_mc_iter_state));
3016 if (!pde)
3017 goto out_igmp;
3018 pde = proc_create_net("mcfilter", 0444, net->proc_net,
3019 &igmp_mcf_seq_ops, sizeof(struct igmp_mcf_iter_state));
3020 if (!pde)
3021 goto out_mcfilter;
3022 err = inet_ctl_sock_create(&net->ipv4.mc_autojoin_sk, AF_INET,
3023 SOCK_DGRAM, 0, net);
3024 if (err < 0) {
3025 pr_err("Failed to initialize the IGMP autojoin socket (err %d)\n",
3026 err);
3027 goto out_sock;
3028 }
3029
3030 return 0;
3031
3032 out_sock:
3033 remove_proc_entry("mcfilter", net->proc_net);
3034 out_mcfilter:
3035 remove_proc_entry("igmp", net->proc_net);
3036 out_igmp:
3037 return -ENOMEM;
3038 }
3039
3040 static void __net_exit igmp_net_exit(struct net *net)
3041 {
3042 remove_proc_entry("mcfilter", net->proc_net);
3043 remove_proc_entry("igmp", net->proc_net);
3044 inet_ctl_sock_destroy(net->ipv4.mc_autojoin_sk);
3045 }
3046
3047 static struct pernet_operations igmp_net_ops = {
3048 .init = igmp_net_init,
3049 .exit = igmp_net_exit,
3050 };
3051 #endif
3052
3053 static int igmp_netdev_event(struct notifier_block *this,
3054 unsigned long event, void *ptr)
3055 {
3056 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3057 struct in_device *in_dev;
3058
3059 switch (event) {
3060 case NETDEV_RESEND_IGMP:
3061 in_dev = __in_dev_get_rtnl(dev);
3062 if (in_dev)
3063 ip_mc_rejoin_groups(in_dev);
3064 break;
3065 default:
3066 break;
3067 }
3068 return NOTIFY_DONE;
3069 }
3070
3071 static struct notifier_block igmp_notifier = {
3072 .notifier_call = igmp_netdev_event,
3073 };
3074
3075 int __init igmp_mc_init(void)
3076 {
3077 #if defined(CONFIG_PROC_FS)
3078 int err;
3079
3080 err = register_pernet_subsys(&igmp_net_ops);
3081 if (err)
3082 return err;
3083 err = register_netdevice_notifier(&igmp_notifier);
3084 if (err)
3085 goto reg_notif_fail;
3086 return 0;
3087
3088 reg_notif_fail:
3089 unregister_pernet_subsys(&igmp_net_ops);
3090 return err;
3091 #else
3092 return register_netdevice_notifier(&igmp_notifier);
3093 #endif
3094 }
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