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