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

Provided by KDAB

Privacy Policy
Improve your Profiling and Debugging skills
Find out more

source code of linux/net/ipv4/igmp.c