1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Multicast support for IPv6
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *
9  *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
10  */
11 
12 /* Changes:
13  *
14  *	yoshfuji	: fix format of router-alert option
15  *	YOSHIFUJI Hideaki @USAGI:
16  *		Fixed source address for MLD message based on
17  *		<draft-ietf-magma-mld-source-05.txt>.
18  *	YOSHIFUJI Hideaki @USAGI:
19  *		- Ignore Queries for invalid addresses.
20  *		- MLD for link-local addresses.
21  *	David L Stevens <dlstevens@us.ibm.com>:
22  *		- MLDv2 support
23  */
24 
25 #include <linux/module.h>
26 #include <linux/errno.h>
27 #include <linux/types.h>
28 #include <linux/string.h>
29 #include <linux/socket.h>
30 #include <linux/sockios.h>
31 #include <linux/jiffies.h>
32 #include <linux/net.h>
33 #include <linux/in.h>
34 #include <linux/in6.h>
35 #include <linux/netdevice.h>
36 #include <linux/if_arp.h>
37 #include <linux/route.h>
38 #include <linux/init.h>
39 #include <linux/proc_fs.h>
40 #include <linux/seq_file.h>
41 #include <linux/slab.h>
42 #include <linux/pkt_sched.h>
43 #include <net/mld.h>
44 #include <linux/workqueue.h>
45 
46 #include <linux/netfilter.h>
47 #include <linux/netfilter_ipv6.h>
48 
49 #include <net/net_namespace.h>
50 #include <net/sock.h>
51 #include <net/snmp.h>
52 
53 #include <net/ipv6.h>
54 #include <net/protocol.h>
55 #include <net/if_inet6.h>
56 #include <net/ndisc.h>
57 #include <net/addrconf.h>
58 #include <net/ip6_route.h>
59 #include <net/inet_common.h>
60 
61 #include <net/ip6_checksum.h>
62 
63 /* Ensure that we have struct in6_addr aligned on 32bit word. */
64 static int __mld2_query_bugs[] __attribute__((__unused__)) = {
65 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_query, mld2q_srcs) % 4),
66 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_report, mld2r_grec) % 4),
67 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_grec, grec_mca) % 4)
68 };
69 
70 static struct workqueue_struct *mld_wq;
71 static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
72 
73 static void igmp6_join_group(struct ifmcaddr6 *ma);
74 static void igmp6_leave_group(struct ifmcaddr6 *ma);
75 static void mld_mca_work(struct work_struct *work);
76 
77 static void mld_ifc_event(struct inet6_dev *idev);
78 static bool mld_in_v1_mode(const struct inet6_dev *idev);
79 static int sf_setstate(struct ifmcaddr6 *pmc);
80 static void sf_markstate(struct ifmcaddr6 *pmc);
81 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
82 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
83 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
84 			  int delta);
85 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
86 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
87 			  int delta);
88 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
89 			    struct inet6_dev *idev);
90 static int __ipv6_dev_mc_inc(struct net_device *dev,
91 			     const struct in6_addr *addr, unsigned int mode);
92 
93 #define MLD_QRV_DEFAULT		2
94 /* RFC3810, 9.2. Query Interval */
95 #define MLD_QI_DEFAULT		(125 * HZ)
96 /* RFC3810, 9.3. Query Response Interval */
97 #define MLD_QRI_DEFAULT		(10 * HZ)
98 
99 /* RFC3810, 8.1 Query Version Distinctions */
100 #define MLD_V1_QUERY_LEN	24
101 #define MLD_V2_QUERY_LEN_MIN	28
102 
103 #define IPV6_MLD_MAX_MSF	64
104 
105 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
106 int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
107 
108 /*
109  *	socket join on multicast group
110  */
111 #define mc_dereference(e, idev) \
112 	rcu_dereference_protected(e, lockdep_is_held(&(idev)->mc_lock))
113 
114 #define sock_dereference(e, sk) \
115 	rcu_dereference_protected(e, lockdep_sock_is_held(sk))
116 
117 #define for_each_pmc_socklock(np, sk, pmc)			\
118 	for (pmc = sock_dereference((np)->ipv6_mc_list, sk);	\
119 	     pmc;						\
120 	     pmc = sock_dereference(pmc->next, sk))
121 
122 #define for_each_pmc_rcu(np, pmc)				\
123 	for (pmc = rcu_dereference((np)->ipv6_mc_list);		\
124 	     pmc;						\
125 	     pmc = rcu_dereference(pmc->next))
126 
127 #define for_each_psf_mclock(mc, psf)				\
128 	for (psf = mc_dereference((mc)->mca_sources, mc->idev);	\
129 	     psf;						\
130 	     psf = mc_dereference(psf->sf_next, mc->idev))
131 
132 #define for_each_psf_rcu(mc, psf)				\
133 	for (psf = rcu_dereference((mc)->mca_sources);		\
134 	     psf;						\
135 	     psf = rcu_dereference(psf->sf_next))
136 
137 #define for_each_psf_tomb(mc, psf)				\
138 	for (psf = mc_dereference((mc)->mca_tomb, mc->idev);	\
139 	     psf;						\
140 	     psf = mc_dereference(psf->sf_next, mc->idev))
141 
142 #define for_each_mc_mclock(idev, mc)				\
143 	for (mc = mc_dereference((idev)->mc_list, idev);	\
144 	     mc;						\
145 	     mc = mc_dereference(mc->next, idev))
146 
147 #define for_each_mc_rcu(idev, mc)				\
148 	for (mc = rcu_dereference((idev)->mc_list);             \
149 	     mc;                                                \
150 	     mc = rcu_dereference(mc->next))
151 
152 #define for_each_mc_tomb(idev, mc)				\
153 	for (mc = mc_dereference((idev)->mc_tomb, idev);	\
154 	     mc;						\
155 	     mc = mc_dereference(mc->next, idev))
156 
unsolicited_report_interval(struct inet6_dev * idev)157 static int unsolicited_report_interval(struct inet6_dev *idev)
158 {
159 	int iv;
160 
161 	if (mld_in_v1_mode(idev))
162 		iv = idev->cnf.mldv1_unsolicited_report_interval;
163 	else
164 		iv = idev->cnf.mldv2_unsolicited_report_interval;
165 
166 	return iv > 0 ? iv : 1;
167 }
168 
__ipv6_sock_mc_join(struct sock * sk,int ifindex,const struct in6_addr * addr,unsigned int mode)169 static int __ipv6_sock_mc_join(struct sock *sk, int ifindex,
170 			       const struct in6_addr *addr, unsigned int mode)
171 {
172 	struct net_device *dev = NULL;
173 	struct ipv6_mc_socklist *mc_lst;
174 	struct ipv6_pinfo *np = inet6_sk(sk);
175 	struct net *net = sock_net(sk);
176 	int err;
177 
178 	ASSERT_RTNL();
179 
180 	if (!ipv6_addr_is_multicast(addr))
181 		return -EINVAL;
182 
183 	for_each_pmc_socklock(np, sk, mc_lst) {
184 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
185 		    ipv6_addr_equal(&mc_lst->addr, addr))
186 			return -EADDRINUSE;
187 	}
188 
189 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
190 
191 	if (!mc_lst)
192 		return -ENOMEM;
193 
194 	mc_lst->next = NULL;
195 	mc_lst->addr = *addr;
196 
197 	if (ifindex == 0) {
198 		struct rt6_info *rt;
199 		rt = rt6_lookup(net, addr, NULL, 0, NULL, 0);
200 		if (rt) {
201 			dev = rt->dst.dev;
202 			ip6_rt_put(rt);
203 		}
204 	} else
205 		dev = __dev_get_by_index(net, ifindex);
206 
207 	if (!dev) {
208 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
209 		return -ENODEV;
210 	}
211 
212 	mc_lst->ifindex = dev->ifindex;
213 	mc_lst->sfmode = mode;
214 	RCU_INIT_POINTER(mc_lst->sflist, NULL);
215 
216 	/*
217 	 *	now add/increase the group membership on the device
218 	 */
219 
220 	err = __ipv6_dev_mc_inc(dev, addr, mode);
221 
222 	if (err) {
223 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
224 		return err;
225 	}
226 
227 	mc_lst->next = np->ipv6_mc_list;
228 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
229 
230 	return 0;
231 }
232 
ipv6_sock_mc_join(struct sock * sk,int ifindex,const struct in6_addr * addr)233 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
234 {
235 	return __ipv6_sock_mc_join(sk, ifindex, addr, MCAST_EXCLUDE);
236 }
237 EXPORT_SYMBOL(ipv6_sock_mc_join);
238 
ipv6_sock_mc_join_ssm(struct sock * sk,int ifindex,const struct in6_addr * addr,unsigned int mode)239 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
240 			  const struct in6_addr *addr, unsigned int mode)
241 {
242 	return __ipv6_sock_mc_join(sk, ifindex, addr, mode);
243 }
244 
245 /*
246  *	socket leave on multicast group
247  */
ipv6_sock_mc_drop(struct sock * sk,int ifindex,const struct in6_addr * addr)248 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
249 {
250 	struct ipv6_pinfo *np = inet6_sk(sk);
251 	struct ipv6_mc_socklist *mc_lst;
252 	struct ipv6_mc_socklist __rcu **lnk;
253 	struct net *net = sock_net(sk);
254 
255 	ASSERT_RTNL();
256 
257 	if (!ipv6_addr_is_multicast(addr))
258 		return -EINVAL;
259 
260 	for (lnk = &np->ipv6_mc_list;
261 	     (mc_lst = sock_dereference(*lnk, sk)) != NULL;
262 	      lnk = &mc_lst->next) {
263 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
264 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
265 			struct net_device *dev;
266 
267 			*lnk = mc_lst->next;
268 
269 			dev = __dev_get_by_index(net, mc_lst->ifindex);
270 			if (dev) {
271 				struct inet6_dev *idev = __in6_dev_get(dev);
272 
273 				ip6_mc_leave_src(sk, mc_lst, idev);
274 				if (idev)
275 					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
276 			} else {
277 				ip6_mc_leave_src(sk, mc_lst, NULL);
278 			}
279 
280 			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
281 			kfree_rcu(mc_lst, rcu);
282 			return 0;
283 		}
284 	}
285 
286 	return -EADDRNOTAVAIL;
287 }
288 EXPORT_SYMBOL(ipv6_sock_mc_drop);
289 
ip6_mc_find_dev_rtnl(struct net * net,const struct in6_addr * group,int ifindex)290 static struct inet6_dev *ip6_mc_find_dev_rtnl(struct net *net,
291 					      const struct in6_addr *group,
292 					      int ifindex)
293 {
294 	struct net_device *dev = NULL;
295 	struct inet6_dev *idev = NULL;
296 
297 	if (ifindex == 0) {
298 		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, NULL, 0);
299 
300 		if (rt) {
301 			dev = rt->dst.dev;
302 			ip6_rt_put(rt);
303 		}
304 	} else {
305 		dev = __dev_get_by_index(net, ifindex);
306 	}
307 
308 	if (!dev)
309 		return NULL;
310 	idev = __in6_dev_get(dev);
311 	if (!idev)
312 		return NULL;
313 	if (idev->dead)
314 		return NULL;
315 	return idev;
316 }
317 
__ipv6_sock_mc_close(struct sock * sk)318 void __ipv6_sock_mc_close(struct sock *sk)
319 {
320 	struct ipv6_pinfo *np = inet6_sk(sk);
321 	struct ipv6_mc_socklist *mc_lst;
322 	struct net *net = sock_net(sk);
323 
324 	ASSERT_RTNL();
325 
326 	while ((mc_lst = sock_dereference(np->ipv6_mc_list, sk)) != NULL) {
327 		struct net_device *dev;
328 
329 		np->ipv6_mc_list = mc_lst->next;
330 
331 		dev = __dev_get_by_index(net, mc_lst->ifindex);
332 		if (dev) {
333 			struct inet6_dev *idev = __in6_dev_get(dev);
334 
335 			ip6_mc_leave_src(sk, mc_lst, idev);
336 			if (idev)
337 				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
338 		} else {
339 			ip6_mc_leave_src(sk, mc_lst, NULL);
340 		}
341 
342 		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
343 		kfree_rcu(mc_lst, rcu);
344 	}
345 }
346 
ipv6_sock_mc_close(struct sock * sk)347 void ipv6_sock_mc_close(struct sock *sk)
348 {
349 	struct ipv6_pinfo *np = inet6_sk(sk);
350 
351 	if (!rcu_access_pointer(np->ipv6_mc_list))
352 		return;
353 
354 	rtnl_lock();
355 	lock_sock(sk);
356 	__ipv6_sock_mc_close(sk);
357 	release_sock(sk);
358 	rtnl_unlock();
359 }
360 
ip6_mc_source(int add,int omode,struct sock * sk,struct group_source_req * pgsr)361 int ip6_mc_source(int add, int omode, struct sock *sk,
362 	struct group_source_req *pgsr)
363 {
364 	struct in6_addr *source, *group;
365 	struct ipv6_mc_socklist *pmc;
366 	struct inet6_dev *idev;
367 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
368 	struct ip6_sf_socklist *psl;
369 	struct net *net = sock_net(sk);
370 	int i, j, rv;
371 	int leavegroup = 0;
372 	int err;
373 
374 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
375 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
376 
377 	if (!ipv6_addr_is_multicast(group))
378 		return -EINVAL;
379 
380 	idev = ip6_mc_find_dev_rtnl(net, group, pgsr->gsr_interface);
381 	if (!idev)
382 		return -ENODEV;
383 
384 	err = -EADDRNOTAVAIL;
385 
386 	mutex_lock(&idev->mc_lock);
387 	for_each_pmc_socklock(inet6, sk, pmc) {
388 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
389 			continue;
390 		if (ipv6_addr_equal(&pmc->addr, group))
391 			break;
392 	}
393 	if (!pmc) {		/* must have a prior join */
394 		err = -EINVAL;
395 		goto done;
396 	}
397 	/* if a source filter was set, must be the same mode as before */
398 	if (rcu_access_pointer(pmc->sflist)) {
399 		if (pmc->sfmode != omode) {
400 			err = -EINVAL;
401 			goto done;
402 		}
403 	} else if (pmc->sfmode != omode) {
404 		/* allow mode switches for empty-set filters */
405 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
406 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
407 		pmc->sfmode = omode;
408 	}
409 
410 	psl = sock_dereference(pmc->sflist, sk);
411 	if (!add) {
412 		if (!psl)
413 			goto done;	/* err = -EADDRNOTAVAIL */
414 		rv = !0;
415 		for (i = 0; i < psl->sl_count; i++) {
416 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
417 			if (rv == 0)
418 				break;
419 		}
420 		if (rv)		/* source not found */
421 			goto done;	/* err = -EADDRNOTAVAIL */
422 
423 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
424 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
425 			leavegroup = 1;
426 			goto done;
427 		}
428 
429 		/* update the interface filter */
430 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
431 
432 		for (j = i+1; j < psl->sl_count; j++)
433 			psl->sl_addr[j-1] = psl->sl_addr[j];
434 		psl->sl_count--;
435 		err = 0;
436 		goto done;
437 	}
438 	/* else, add a new source to the filter */
439 
440 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
441 		err = -ENOBUFS;
442 		goto done;
443 	}
444 	if (!psl || psl->sl_count == psl->sl_max) {
445 		struct ip6_sf_socklist *newpsl;
446 		int count = IP6_SFBLOCK;
447 
448 		if (psl)
449 			count += psl->sl_max;
450 		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count),
451 				      GFP_KERNEL);
452 		if (!newpsl) {
453 			err = -ENOBUFS;
454 			goto done;
455 		}
456 		newpsl->sl_max = count;
457 		newpsl->sl_count = count - IP6_SFBLOCK;
458 		if (psl) {
459 			for (i = 0; i < psl->sl_count; i++)
460 				newpsl->sl_addr[i] = psl->sl_addr[i];
461 			atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
462 				   &sk->sk_omem_alloc);
463 		}
464 		rcu_assign_pointer(pmc->sflist, newpsl);
465 		kfree_rcu(psl, rcu);
466 		psl = newpsl;
467 	}
468 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
469 	for (i = 0; i < psl->sl_count; i++) {
470 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
471 		if (rv == 0) /* There is an error in the address. */
472 			goto done;
473 	}
474 	for (j = psl->sl_count-1; j >= i; j--)
475 		psl->sl_addr[j+1] = psl->sl_addr[j];
476 	psl->sl_addr[i] = *source;
477 	psl->sl_count++;
478 	err = 0;
479 	/* update the interface list */
480 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
481 done:
482 	mutex_unlock(&idev->mc_lock);
483 	if (leavegroup)
484 		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
485 	return err;
486 }
487 
ip6_mc_msfilter(struct sock * sk,struct group_filter * gsf,struct sockaddr_storage * list)488 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
489 		    struct sockaddr_storage *list)
490 {
491 	const struct in6_addr *group;
492 	struct ipv6_mc_socklist *pmc;
493 	struct inet6_dev *idev;
494 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
495 	struct ip6_sf_socklist *newpsl, *psl;
496 	struct net *net = sock_net(sk);
497 	int leavegroup = 0;
498 	int i, err;
499 
500 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
501 
502 	if (!ipv6_addr_is_multicast(group))
503 		return -EINVAL;
504 	if (gsf->gf_fmode != MCAST_INCLUDE &&
505 	    gsf->gf_fmode != MCAST_EXCLUDE)
506 		return -EINVAL;
507 
508 	idev = ip6_mc_find_dev_rtnl(net, group, gsf->gf_interface);
509 	if (!idev)
510 		return -ENODEV;
511 
512 	err = 0;
513 
514 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
515 		leavegroup = 1;
516 		goto done;
517 	}
518 
519 	for_each_pmc_socklock(inet6, sk, pmc) {
520 		if (pmc->ifindex != gsf->gf_interface)
521 			continue;
522 		if (ipv6_addr_equal(&pmc->addr, group))
523 			break;
524 	}
525 	if (!pmc) {		/* must have a prior join */
526 		err = -EINVAL;
527 		goto done;
528 	}
529 	if (gsf->gf_numsrc) {
530 		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr,
531 						      gsf->gf_numsrc),
532 				      GFP_KERNEL);
533 		if (!newpsl) {
534 			err = -ENOBUFS;
535 			goto done;
536 		}
537 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
538 		for (i = 0; i < newpsl->sl_count; ++i, ++list) {
539 			struct sockaddr_in6 *psin6;
540 
541 			psin6 = (struct sockaddr_in6 *)list;
542 			newpsl->sl_addr[i] = psin6->sin6_addr;
543 		}
544 		mutex_lock(&idev->mc_lock);
545 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
546 				     newpsl->sl_count, newpsl->sl_addr, 0);
547 		if (err) {
548 			mutex_unlock(&idev->mc_lock);
549 			sock_kfree_s(sk, newpsl, struct_size(newpsl, sl_addr,
550 							     newpsl->sl_max));
551 			goto done;
552 		}
553 		mutex_unlock(&idev->mc_lock);
554 	} else {
555 		newpsl = NULL;
556 		mutex_lock(&idev->mc_lock);
557 		ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
558 		mutex_unlock(&idev->mc_lock);
559 	}
560 
561 	mutex_lock(&idev->mc_lock);
562 	psl = sock_dereference(pmc->sflist, sk);
563 	if (psl) {
564 		ip6_mc_del_src(idev, group, pmc->sfmode,
565 			       psl->sl_count, psl->sl_addr, 0);
566 		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
567 			   &sk->sk_omem_alloc);
568 	} else {
569 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
570 	}
571 	rcu_assign_pointer(pmc->sflist, newpsl);
572 	mutex_unlock(&idev->mc_lock);
573 	kfree_rcu(psl, rcu);
574 	pmc->sfmode = gsf->gf_fmode;
575 	err = 0;
576 done:
577 	if (leavegroup)
578 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
579 	return err;
580 }
581 
ip6_mc_msfget(struct sock * sk,struct group_filter * gsf,sockptr_t optval,size_t ss_offset)582 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
583 		  sockptr_t optval, size_t ss_offset)
584 {
585 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
586 	const struct in6_addr *group;
587 	struct ipv6_mc_socklist *pmc;
588 	struct ip6_sf_socklist *psl;
589 	int i, count, copycount;
590 
591 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
592 
593 	if (!ipv6_addr_is_multicast(group))
594 		return -EINVAL;
595 
596 	/* changes to the ipv6_mc_list require the socket lock and
597 	 * rtnl lock. We have the socket lock, so reading the list is safe.
598 	 */
599 
600 	for_each_pmc_socklock(inet6, sk, pmc) {
601 		if (pmc->ifindex != gsf->gf_interface)
602 			continue;
603 		if (ipv6_addr_equal(group, &pmc->addr))
604 			break;
605 	}
606 	if (!pmc)		/* must have a prior join */
607 		return -EADDRNOTAVAIL;
608 
609 	gsf->gf_fmode = pmc->sfmode;
610 	psl = sock_dereference(pmc->sflist, sk);
611 	count = psl ? psl->sl_count : 0;
612 
613 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
614 	gsf->gf_numsrc = count;
615 	for (i = 0; i < copycount; i++) {
616 		struct sockaddr_in6 *psin6;
617 		struct sockaddr_storage ss;
618 
619 		psin6 = (struct sockaddr_in6 *)&ss;
620 		memset(&ss, 0, sizeof(ss));
621 		psin6->sin6_family = AF_INET6;
622 		psin6->sin6_addr = psl->sl_addr[i];
623 		if (copy_to_sockptr_offset(optval, ss_offset, &ss, sizeof(ss)))
624 			return -EFAULT;
625 		ss_offset += sizeof(ss);
626 	}
627 	return 0;
628 }
629 
inet6_mc_check(struct sock * sk,const struct in6_addr * mc_addr,const struct in6_addr * src_addr)630 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
631 		    const struct in6_addr *src_addr)
632 {
633 	struct ipv6_pinfo *np = inet6_sk(sk);
634 	struct ipv6_mc_socklist *mc;
635 	struct ip6_sf_socklist *psl;
636 	bool rv = true;
637 
638 	rcu_read_lock();
639 	for_each_pmc_rcu(np, mc) {
640 		if (ipv6_addr_equal(&mc->addr, mc_addr))
641 			break;
642 	}
643 	if (!mc) {
644 		rcu_read_unlock();
645 		return np->mc_all;
646 	}
647 	psl = rcu_dereference(mc->sflist);
648 	if (!psl) {
649 		rv = mc->sfmode == MCAST_EXCLUDE;
650 	} else {
651 		int i;
652 
653 		for (i = 0; i < psl->sl_count; i++) {
654 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
655 				break;
656 		}
657 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
658 			rv = false;
659 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
660 			rv = false;
661 	}
662 	rcu_read_unlock();
663 
664 	return rv;
665 }
666 
667 /* called with mc_lock */
igmp6_group_added(struct ifmcaddr6 * mc)668 static void igmp6_group_added(struct ifmcaddr6 *mc)
669 {
670 	struct net_device *dev = mc->idev->dev;
671 	char buf[MAX_ADDR_LEN];
672 
673 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
674 	    IPV6_ADDR_SCOPE_LINKLOCAL)
675 		return;
676 
677 	if (!(mc->mca_flags&MAF_LOADED)) {
678 		mc->mca_flags |= MAF_LOADED;
679 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
680 			dev_mc_add(dev, buf);
681 	}
682 
683 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
684 		return;
685 
686 	if (mld_in_v1_mode(mc->idev)) {
687 		igmp6_join_group(mc);
688 		return;
689 	}
690 	/* else v2 */
691 
692 	/* Based on RFC3810 6.1, for newly added INCLUDE SSM, we
693 	 * should not send filter-mode change record as the mode
694 	 * should be from IN() to IN(A).
695 	 */
696 	if (mc->mca_sfmode == MCAST_EXCLUDE)
697 		mc->mca_crcount = mc->idev->mc_qrv;
698 
699 	mld_ifc_event(mc->idev);
700 }
701 
702 /* called with mc_lock */
igmp6_group_dropped(struct ifmcaddr6 * mc)703 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
704 {
705 	struct net_device *dev = mc->idev->dev;
706 	char buf[MAX_ADDR_LEN];
707 
708 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
709 	    IPV6_ADDR_SCOPE_LINKLOCAL)
710 		return;
711 
712 	if (mc->mca_flags&MAF_LOADED) {
713 		mc->mca_flags &= ~MAF_LOADED;
714 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
715 			dev_mc_del(dev, buf);
716 	}
717 
718 	if (mc->mca_flags & MAF_NOREPORT)
719 		return;
720 
721 	if (!mc->idev->dead)
722 		igmp6_leave_group(mc);
723 
724 	if (cancel_delayed_work(&mc->mca_work))
725 		refcount_dec(&mc->mca_refcnt);
726 }
727 
728 /*
729  * deleted ifmcaddr6 manipulation
730  * called with mc_lock
731  */
mld_add_delrec(struct inet6_dev * idev,struct ifmcaddr6 * im)732 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
733 {
734 	struct ifmcaddr6 *pmc;
735 
736 	/* this is an "ifmcaddr6" for convenience; only the fields below
737 	 * are actually used. In particular, the refcnt and users are not
738 	 * used for management of the delete list. Using the same structure
739 	 * for deleted items allows change reports to use common code with
740 	 * non-deleted or query-response MCA's.
741 	 */
742 	pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
743 	if (!pmc)
744 		return;
745 
746 	pmc->idev = im->idev;
747 	in6_dev_hold(idev);
748 	pmc->mca_addr = im->mca_addr;
749 	pmc->mca_crcount = idev->mc_qrv;
750 	pmc->mca_sfmode = im->mca_sfmode;
751 	if (pmc->mca_sfmode == MCAST_INCLUDE) {
752 		struct ip6_sf_list *psf;
753 
754 		rcu_assign_pointer(pmc->mca_tomb,
755 				   mc_dereference(im->mca_tomb, idev));
756 		rcu_assign_pointer(pmc->mca_sources,
757 				   mc_dereference(im->mca_sources, idev));
758 		RCU_INIT_POINTER(im->mca_tomb, NULL);
759 		RCU_INIT_POINTER(im->mca_sources, NULL);
760 
761 		for_each_psf_mclock(pmc, psf)
762 			psf->sf_crcount = pmc->mca_crcount;
763 	}
764 
765 	rcu_assign_pointer(pmc->next, idev->mc_tomb);
766 	rcu_assign_pointer(idev->mc_tomb, pmc);
767 }
768 
769 /* called with mc_lock */
mld_del_delrec(struct inet6_dev * idev,struct ifmcaddr6 * im)770 static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
771 {
772 	struct ip6_sf_list *psf, *sources, *tomb;
773 	struct in6_addr *pmca = &im->mca_addr;
774 	struct ifmcaddr6 *pmc, *pmc_prev;
775 
776 	pmc_prev = NULL;
777 	for_each_mc_tomb(idev, pmc) {
778 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
779 			break;
780 		pmc_prev = pmc;
781 	}
782 	if (pmc) {
783 		if (pmc_prev)
784 			rcu_assign_pointer(pmc_prev->next, pmc->next);
785 		else
786 			rcu_assign_pointer(idev->mc_tomb, pmc->next);
787 	}
788 
789 	if (pmc) {
790 		im->idev = pmc->idev;
791 		if (im->mca_sfmode == MCAST_INCLUDE) {
792 			tomb = rcu_replace_pointer(im->mca_tomb,
793 						   mc_dereference(pmc->mca_tomb, pmc->idev),
794 						   lockdep_is_held(&im->idev->mc_lock));
795 			rcu_assign_pointer(pmc->mca_tomb, tomb);
796 
797 			sources = rcu_replace_pointer(im->mca_sources,
798 						      mc_dereference(pmc->mca_sources, pmc->idev),
799 						      lockdep_is_held(&im->idev->mc_lock));
800 			rcu_assign_pointer(pmc->mca_sources, sources);
801 			for_each_psf_mclock(im, psf)
802 				psf->sf_crcount = idev->mc_qrv;
803 		} else {
804 			im->mca_crcount = idev->mc_qrv;
805 		}
806 		in6_dev_put(pmc->idev);
807 		ip6_mc_clear_src(pmc);
808 		kfree_rcu(pmc, rcu);
809 	}
810 }
811 
812 /* called with mc_lock */
mld_clear_delrec(struct inet6_dev * idev)813 static void mld_clear_delrec(struct inet6_dev *idev)
814 {
815 	struct ifmcaddr6 *pmc, *nextpmc;
816 
817 	pmc = mc_dereference(idev->mc_tomb, idev);
818 	RCU_INIT_POINTER(idev->mc_tomb, NULL);
819 
820 	for (; pmc; pmc = nextpmc) {
821 		nextpmc = mc_dereference(pmc->next, idev);
822 		ip6_mc_clear_src(pmc);
823 		in6_dev_put(pmc->idev);
824 		kfree_rcu(pmc, rcu);
825 	}
826 
827 	/* clear dead sources, too */
828 	for_each_mc_mclock(idev, pmc) {
829 		struct ip6_sf_list *psf, *psf_next;
830 
831 		psf = mc_dereference(pmc->mca_tomb, idev);
832 		RCU_INIT_POINTER(pmc->mca_tomb, NULL);
833 		for (; psf; psf = psf_next) {
834 			psf_next = mc_dereference(psf->sf_next, idev);
835 			kfree_rcu(psf, rcu);
836 		}
837 	}
838 }
839 
mld_clear_query(struct inet6_dev * idev)840 static void mld_clear_query(struct inet6_dev *idev)
841 {
842 	struct sk_buff *skb;
843 
844 	spin_lock_bh(&idev->mc_query_lock);
845 	while ((skb = __skb_dequeue(&idev->mc_query_queue)))
846 		kfree_skb(skb);
847 	spin_unlock_bh(&idev->mc_query_lock);
848 }
849 
mld_clear_report(struct inet6_dev * idev)850 static void mld_clear_report(struct inet6_dev *idev)
851 {
852 	struct sk_buff *skb;
853 
854 	spin_lock_bh(&idev->mc_report_lock);
855 	while ((skb = __skb_dequeue(&idev->mc_report_queue)))
856 		kfree_skb(skb);
857 	spin_unlock_bh(&idev->mc_report_lock);
858 }
859 
mca_get(struct ifmcaddr6 * mc)860 static void mca_get(struct ifmcaddr6 *mc)
861 {
862 	refcount_inc(&mc->mca_refcnt);
863 }
864 
ma_put(struct ifmcaddr6 * mc)865 static void ma_put(struct ifmcaddr6 *mc)
866 {
867 	if (refcount_dec_and_test(&mc->mca_refcnt)) {
868 		in6_dev_put(mc->idev);
869 		kfree_rcu(mc, rcu);
870 	}
871 }
872 
873 /* called with mc_lock */
mca_alloc(struct inet6_dev * idev,const struct in6_addr * addr,unsigned int mode)874 static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
875 				   const struct in6_addr *addr,
876 				   unsigned int mode)
877 {
878 	struct ifmcaddr6 *mc;
879 
880 	mc = kzalloc(sizeof(*mc), GFP_KERNEL);
881 	if (!mc)
882 		return NULL;
883 
884 	INIT_DELAYED_WORK(&mc->mca_work, mld_mca_work);
885 
886 	mc->mca_addr = *addr;
887 	mc->idev = idev; /* reference taken by caller */
888 	mc->mca_users = 1;
889 	/* mca_stamp should be updated upon changes */
890 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
891 	refcount_set(&mc->mca_refcnt, 1);
892 
893 	mc->mca_sfmode = mode;
894 	mc->mca_sfcount[mode] = 1;
895 
896 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
897 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
898 		mc->mca_flags |= MAF_NOREPORT;
899 
900 	return mc;
901 }
902 
903 /*
904  *	device multicast group inc (add if not found)
905  */
__ipv6_dev_mc_inc(struct net_device * dev,const struct in6_addr * addr,unsigned int mode)906 static int __ipv6_dev_mc_inc(struct net_device *dev,
907 			     const struct in6_addr *addr, unsigned int mode)
908 {
909 	struct ifmcaddr6 *mc;
910 	struct inet6_dev *idev;
911 
912 	ASSERT_RTNL();
913 
914 	/* we need to take a reference on idev */
915 	idev = in6_dev_get(dev);
916 
917 	if (!idev)
918 		return -EINVAL;
919 
920 	if (idev->dead) {
921 		in6_dev_put(idev);
922 		return -ENODEV;
923 	}
924 
925 	mutex_lock(&idev->mc_lock);
926 	for_each_mc_mclock(idev, mc) {
927 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
928 			mc->mca_users++;
929 			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
930 			mutex_unlock(&idev->mc_lock);
931 			in6_dev_put(idev);
932 			return 0;
933 		}
934 	}
935 
936 	mc = mca_alloc(idev, addr, mode);
937 	if (!mc) {
938 		mutex_unlock(&idev->mc_lock);
939 		in6_dev_put(idev);
940 		return -ENOMEM;
941 	}
942 
943 	rcu_assign_pointer(mc->next, idev->mc_list);
944 	rcu_assign_pointer(idev->mc_list, mc);
945 
946 	mca_get(mc);
947 
948 	mld_del_delrec(idev, mc);
949 	igmp6_group_added(mc);
950 	mutex_unlock(&idev->mc_lock);
951 	ma_put(mc);
952 	return 0;
953 }
954 
ipv6_dev_mc_inc(struct net_device * dev,const struct in6_addr * addr)955 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
956 {
957 	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
958 }
959 EXPORT_SYMBOL(ipv6_dev_mc_inc);
960 
961 /*
962  * device multicast group del
963  */
__ipv6_dev_mc_dec(struct inet6_dev * idev,const struct in6_addr * addr)964 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
965 {
966 	struct ifmcaddr6 *ma, __rcu **map;
967 
968 	ASSERT_RTNL();
969 
970 	mutex_lock(&idev->mc_lock);
971 	for (map = &idev->mc_list;
972 	     (ma = mc_dereference(*map, idev));
973 	     map = &ma->next) {
974 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
975 			if (--ma->mca_users == 0) {
976 				*map = ma->next;
977 
978 				igmp6_group_dropped(ma);
979 				ip6_mc_clear_src(ma);
980 				mutex_unlock(&idev->mc_lock);
981 
982 				ma_put(ma);
983 				return 0;
984 			}
985 			mutex_unlock(&idev->mc_lock);
986 			return 0;
987 		}
988 	}
989 
990 	mutex_unlock(&idev->mc_lock);
991 	return -ENOENT;
992 }
993 
ipv6_dev_mc_dec(struct net_device * dev,const struct in6_addr * addr)994 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
995 {
996 	struct inet6_dev *idev;
997 	int err;
998 
999 	ASSERT_RTNL();
1000 
1001 	idev = __in6_dev_get(dev);
1002 	if (!idev)
1003 		err = -ENODEV;
1004 	else
1005 		err = __ipv6_dev_mc_dec(idev, addr);
1006 
1007 	return err;
1008 }
1009 EXPORT_SYMBOL(ipv6_dev_mc_dec);
1010 
1011 /*
1012  *	check if the interface/address pair is valid
1013  */
ipv6_chk_mcast_addr(struct net_device * dev,const struct in6_addr * group,const struct in6_addr * src_addr)1014 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
1015 			 const struct in6_addr *src_addr)
1016 {
1017 	struct inet6_dev *idev;
1018 	struct ifmcaddr6 *mc;
1019 	bool rv = false;
1020 
1021 	rcu_read_lock();
1022 	idev = __in6_dev_get(dev);
1023 	if (idev) {
1024 		for_each_mc_rcu(idev, mc) {
1025 			if (ipv6_addr_equal(&mc->mca_addr, group))
1026 				break;
1027 		}
1028 		if (mc) {
1029 			if (src_addr && !ipv6_addr_any(src_addr)) {
1030 				struct ip6_sf_list *psf;
1031 
1032 				for_each_psf_rcu(mc, psf) {
1033 					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
1034 						break;
1035 				}
1036 				if (psf)
1037 					rv = psf->sf_count[MCAST_INCLUDE] ||
1038 						psf->sf_count[MCAST_EXCLUDE] !=
1039 						mc->mca_sfcount[MCAST_EXCLUDE];
1040 				else
1041 					rv = mc->mca_sfcount[MCAST_EXCLUDE] != 0;
1042 			} else
1043 				rv = true; /* don't filter unspecified source */
1044 		}
1045 	}
1046 	rcu_read_unlock();
1047 	return rv;
1048 }
1049 
1050 /* called with mc_lock */
mld_gq_start_work(struct inet6_dev * idev)1051 static void mld_gq_start_work(struct inet6_dev *idev)
1052 {
1053 	unsigned long tv = prandom_u32_max(idev->mc_maxdelay);
1054 
1055 	idev->mc_gq_running = 1;
1056 	if (!mod_delayed_work(mld_wq, &idev->mc_gq_work, tv + 2))
1057 		in6_dev_hold(idev);
1058 }
1059 
1060 /* called with mc_lock */
mld_gq_stop_work(struct inet6_dev * idev)1061 static void mld_gq_stop_work(struct inet6_dev *idev)
1062 {
1063 	idev->mc_gq_running = 0;
1064 	if (cancel_delayed_work(&idev->mc_gq_work))
1065 		__in6_dev_put(idev);
1066 }
1067 
1068 /* called with mc_lock */
mld_ifc_start_work(struct inet6_dev * idev,unsigned long delay)1069 static void mld_ifc_start_work(struct inet6_dev *idev, unsigned long delay)
1070 {
1071 	unsigned long tv = prandom_u32_max(delay);
1072 
1073 	if (!mod_delayed_work(mld_wq, &idev->mc_ifc_work, tv + 2))
1074 		in6_dev_hold(idev);
1075 }
1076 
1077 /* called with mc_lock */
mld_ifc_stop_work(struct inet6_dev * idev)1078 static void mld_ifc_stop_work(struct inet6_dev *idev)
1079 {
1080 	idev->mc_ifc_count = 0;
1081 	if (cancel_delayed_work(&idev->mc_ifc_work))
1082 		__in6_dev_put(idev);
1083 }
1084 
1085 /* called with mc_lock */
mld_dad_start_work(struct inet6_dev * idev,unsigned long delay)1086 static void mld_dad_start_work(struct inet6_dev *idev, unsigned long delay)
1087 {
1088 	unsigned long tv = prandom_u32_max(delay);
1089 
1090 	if (!mod_delayed_work(mld_wq, &idev->mc_dad_work, tv + 2))
1091 		in6_dev_hold(idev);
1092 }
1093 
mld_dad_stop_work(struct inet6_dev * idev)1094 static void mld_dad_stop_work(struct inet6_dev *idev)
1095 {
1096 	if (cancel_delayed_work(&idev->mc_dad_work))
1097 		__in6_dev_put(idev);
1098 }
1099 
mld_query_stop_work(struct inet6_dev * idev)1100 static void mld_query_stop_work(struct inet6_dev *idev)
1101 {
1102 	spin_lock_bh(&idev->mc_query_lock);
1103 	if (cancel_delayed_work(&idev->mc_query_work))
1104 		__in6_dev_put(idev);
1105 	spin_unlock_bh(&idev->mc_query_lock);
1106 }
1107 
mld_report_stop_work(struct inet6_dev * idev)1108 static void mld_report_stop_work(struct inet6_dev *idev)
1109 {
1110 	if (cancel_delayed_work_sync(&idev->mc_report_work))
1111 		__in6_dev_put(idev);
1112 }
1113 
1114 /*
1115  * IGMP handling (alias multicast ICMPv6 messages)
1116  * called with mc_lock
1117  */
igmp6_group_queried(struct ifmcaddr6 * ma,unsigned long resptime)1118 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1119 {
1120 	unsigned long delay = resptime;
1121 
1122 	/* Do not start work for these addresses */
1123 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1124 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1125 		return;
1126 
1127 	if (cancel_delayed_work(&ma->mca_work)) {
1128 		refcount_dec(&ma->mca_refcnt);
1129 		delay = ma->mca_work.timer.expires - jiffies;
1130 	}
1131 
1132 	if (delay >= resptime)
1133 		delay = prandom_u32_max(resptime);
1134 
1135 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
1136 		refcount_inc(&ma->mca_refcnt);
1137 	ma->mca_flags |= MAF_TIMER_RUNNING;
1138 }
1139 
1140 /* mark EXCLUDE-mode sources
1141  * called with mc_lock
1142  */
mld_xmarksources(struct ifmcaddr6 * pmc,int nsrcs,const struct in6_addr * srcs)1143 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1144 			     const struct in6_addr *srcs)
1145 {
1146 	struct ip6_sf_list *psf;
1147 	int i, scount;
1148 
1149 	scount = 0;
1150 	for_each_psf_mclock(pmc, psf) {
1151 		if (scount == nsrcs)
1152 			break;
1153 		for (i = 0; i < nsrcs; i++) {
1154 			/* skip inactive filters */
1155 			if (psf->sf_count[MCAST_INCLUDE] ||
1156 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1157 			    psf->sf_count[MCAST_EXCLUDE])
1158 				break;
1159 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1160 				scount++;
1161 				break;
1162 			}
1163 		}
1164 	}
1165 	pmc->mca_flags &= ~MAF_GSQUERY;
1166 	if (scount == nsrcs)	/* all sources excluded */
1167 		return false;
1168 	return true;
1169 }
1170 
1171 /* called with mc_lock */
mld_marksources(struct ifmcaddr6 * pmc,int nsrcs,const struct in6_addr * srcs)1172 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1173 			    const struct in6_addr *srcs)
1174 {
1175 	struct ip6_sf_list *psf;
1176 	int i, scount;
1177 
1178 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1179 		return mld_xmarksources(pmc, nsrcs, srcs);
1180 
1181 	/* mark INCLUDE-mode sources */
1182 
1183 	scount = 0;
1184 	for_each_psf_mclock(pmc, psf) {
1185 		if (scount == nsrcs)
1186 			break;
1187 		for (i = 0; i < nsrcs; i++) {
1188 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1189 				psf->sf_gsresp = 1;
1190 				scount++;
1191 				break;
1192 			}
1193 		}
1194 	}
1195 	if (!scount) {
1196 		pmc->mca_flags &= ~MAF_GSQUERY;
1197 		return false;
1198 	}
1199 	pmc->mca_flags |= MAF_GSQUERY;
1200 	return true;
1201 }
1202 
mld_force_mld_version(const struct inet6_dev * idev)1203 static int mld_force_mld_version(const struct inet6_dev *idev)
1204 {
1205 	/* Normally, both are 0 here. If enforcement to a particular is
1206 	 * being used, individual device enforcement will have a lower
1207 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1208 	 */
1209 
1210 	if (dev_net(idev->dev)->ipv6.devconf_all->force_mld_version != 0)
1211 		return dev_net(idev->dev)->ipv6.devconf_all->force_mld_version;
1212 	else
1213 		return idev->cnf.force_mld_version;
1214 }
1215 
mld_in_v2_mode_only(const struct inet6_dev * idev)1216 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1217 {
1218 	return mld_force_mld_version(idev) == 2;
1219 }
1220 
mld_in_v1_mode_only(const struct inet6_dev * idev)1221 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1222 {
1223 	return mld_force_mld_version(idev) == 1;
1224 }
1225 
mld_in_v1_mode(const struct inet6_dev * idev)1226 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1227 {
1228 	if (mld_in_v2_mode_only(idev))
1229 		return false;
1230 	if (mld_in_v1_mode_only(idev))
1231 		return true;
1232 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1233 		return true;
1234 
1235 	return false;
1236 }
1237 
mld_set_v1_mode(struct inet6_dev * idev)1238 static void mld_set_v1_mode(struct inet6_dev *idev)
1239 {
1240 	/* RFC3810, relevant sections:
1241 	 *  - 9.1. Robustness Variable
1242 	 *  - 9.2. Query Interval
1243 	 *  - 9.3. Query Response Interval
1244 	 *  - 9.12. Older Version Querier Present Timeout
1245 	 */
1246 	unsigned long switchback;
1247 
1248 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1249 
1250 	idev->mc_v1_seen = jiffies + switchback;
1251 }
1252 
mld_update_qrv(struct inet6_dev * idev,const struct mld2_query * mlh2)1253 static void mld_update_qrv(struct inet6_dev *idev,
1254 			   const struct mld2_query *mlh2)
1255 {
1256 	/* RFC3810, relevant sections:
1257 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1258 	 *  - 9.1. Robustness Variable
1259 	 */
1260 
1261 	/* The value of the Robustness Variable MUST NOT be zero,
1262 	 * and SHOULD NOT be one. Catch this here if we ever run
1263 	 * into such a case in future.
1264 	 */
1265 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1266 	WARN_ON(idev->mc_qrv == 0);
1267 
1268 	if (mlh2->mld2q_qrv > 0)
1269 		idev->mc_qrv = mlh2->mld2q_qrv;
1270 
1271 	if (unlikely(idev->mc_qrv < min_qrv)) {
1272 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1273 				     idev->mc_qrv, min_qrv);
1274 		idev->mc_qrv = min_qrv;
1275 	}
1276 }
1277 
mld_update_qi(struct inet6_dev * idev,const struct mld2_query * mlh2)1278 static void mld_update_qi(struct inet6_dev *idev,
1279 			  const struct mld2_query *mlh2)
1280 {
1281 	/* RFC3810, relevant sections:
1282 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1283 	 *  - 9.2. Query Interval
1284 	 *  - 9.12. Older Version Querier Present Timeout
1285 	 *    (the [Query Interval] in the last Query received)
1286 	 */
1287 	unsigned long mc_qqi;
1288 
1289 	if (mlh2->mld2q_qqic < 128) {
1290 		mc_qqi = mlh2->mld2q_qqic;
1291 	} else {
1292 		unsigned long mc_man, mc_exp;
1293 
1294 		mc_exp = MLDV2_QQIC_EXP(mlh2->mld2q_qqic);
1295 		mc_man = MLDV2_QQIC_MAN(mlh2->mld2q_qqic);
1296 
1297 		mc_qqi = (mc_man | 0x10) << (mc_exp + 3);
1298 	}
1299 
1300 	idev->mc_qi = mc_qqi * HZ;
1301 }
1302 
mld_update_qri(struct inet6_dev * idev,const struct mld2_query * mlh2)1303 static void mld_update_qri(struct inet6_dev *idev,
1304 			   const struct mld2_query *mlh2)
1305 {
1306 	/* RFC3810, relevant sections:
1307 	 *  - 5.1.3. Maximum Response Code
1308 	 *  - 9.3. Query Response Interval
1309 	 */
1310 	idev->mc_qri = msecs_to_jiffies(mldv2_mrc(mlh2));
1311 }
1312 
mld_process_v1(struct inet6_dev * idev,struct mld_msg * mld,unsigned long * max_delay,bool v1_query)1313 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1314 			  unsigned long *max_delay, bool v1_query)
1315 {
1316 	unsigned long mldv1_md;
1317 
1318 	/* Ignore v1 queries */
1319 	if (mld_in_v2_mode_only(idev))
1320 		return -EINVAL;
1321 
1322 	mldv1_md = ntohs(mld->mld_maxdelay);
1323 
1324 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1325 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1326 	 * only works when the exponential algorithm is not being
1327 	 * used (as MLDv1 is unaware of such things).
1328 	 *
1329 	 * According to the RFC author, the MLDv2 implementations
1330 	 * he's aware of all use a MRC < 32768 on start up queries.
1331 	 *
1332 	 * Thus, should we *ever* encounter something else larger
1333 	 * than that, just assume the maximum possible within our
1334 	 * reach.
1335 	 */
1336 	if (!v1_query)
1337 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1338 
1339 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1340 
1341 	/* MLDv1 router present: we need to go into v1 mode *only*
1342 	 * when an MLDv1 query is received as per section 9.12. of
1343 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1344 	 * queries MUST be of exactly 24 octets.
1345 	 */
1346 	if (v1_query)
1347 		mld_set_v1_mode(idev);
1348 
1349 	/* cancel MLDv2 report work */
1350 	mld_gq_stop_work(idev);
1351 	/* cancel the interface change work */
1352 	mld_ifc_stop_work(idev);
1353 	/* clear deleted report items */
1354 	mld_clear_delrec(idev);
1355 
1356 	return 0;
1357 }
1358 
mld_process_v2(struct inet6_dev * idev,struct mld2_query * mld,unsigned long * max_delay)1359 static void mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1360 			   unsigned long *max_delay)
1361 {
1362 	*max_delay = max(msecs_to_jiffies(mldv2_mrc(mld)), 1UL);
1363 
1364 	mld_update_qrv(idev, mld);
1365 	mld_update_qi(idev, mld);
1366 	mld_update_qri(idev, mld);
1367 
1368 	idev->mc_maxdelay = *max_delay;
1369 
1370 	return;
1371 }
1372 
1373 /* called with rcu_read_lock() */
igmp6_event_query(struct sk_buff * skb)1374 void igmp6_event_query(struct sk_buff *skb)
1375 {
1376 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1377 
1378 	if (!idev || idev->dead)
1379 		goto out;
1380 
1381 	spin_lock_bh(&idev->mc_query_lock);
1382 	if (skb_queue_len(&idev->mc_query_queue) < MLD_MAX_SKBS) {
1383 		__skb_queue_tail(&idev->mc_query_queue, skb);
1384 		if (!mod_delayed_work(mld_wq, &idev->mc_query_work, 0))
1385 			in6_dev_hold(idev);
1386 		skb = NULL;
1387 	}
1388 	spin_unlock_bh(&idev->mc_query_lock);
1389 out:
1390 	kfree_skb(skb);
1391 }
1392 
__mld_query_work(struct sk_buff * skb)1393 static void __mld_query_work(struct sk_buff *skb)
1394 {
1395 	struct mld2_query *mlh2 = NULL;
1396 	const struct in6_addr *group;
1397 	unsigned long max_delay;
1398 	struct inet6_dev *idev;
1399 	struct ifmcaddr6 *ma;
1400 	struct mld_msg *mld;
1401 	int group_type;
1402 	int mark = 0;
1403 	int len, err;
1404 
1405 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1406 		goto kfree_skb;
1407 
1408 	/* compute payload length excluding extension headers */
1409 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1410 	len -= skb_network_header_len(skb);
1411 
1412 	/* RFC3810 6.2
1413 	 * Upon reception of an MLD message that contains a Query, the node
1414 	 * checks if the source address of the message is a valid link-local
1415 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1416 	 * option is present in the Hop-By-Hop Options header of the IPv6
1417 	 * packet.  If any of these checks fails, the packet is dropped.
1418 	 */
1419 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1420 	    ipv6_hdr(skb)->hop_limit != 1 ||
1421 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1422 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1423 		goto kfree_skb;
1424 
1425 	idev = in6_dev_get(skb->dev);
1426 	if (!idev)
1427 		goto kfree_skb;
1428 
1429 	mld = (struct mld_msg *)icmp6_hdr(skb);
1430 	group = &mld->mld_mca;
1431 	group_type = ipv6_addr_type(group);
1432 
1433 	if (group_type != IPV6_ADDR_ANY &&
1434 	    !(group_type&IPV6_ADDR_MULTICAST))
1435 		goto out;
1436 
1437 	if (len < MLD_V1_QUERY_LEN) {
1438 		goto out;
1439 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1440 		err = mld_process_v1(idev, mld, &max_delay,
1441 				     len == MLD_V1_QUERY_LEN);
1442 		if (err < 0)
1443 			goto out;
1444 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1445 		int srcs_offset = sizeof(struct mld2_query) -
1446 				  sizeof(struct icmp6hdr);
1447 
1448 		if (!pskb_may_pull(skb, srcs_offset))
1449 			goto out;
1450 
1451 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1452 
1453 		mld_process_v2(idev, mlh2, &max_delay);
1454 
1455 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1456 			if (mlh2->mld2q_nsrcs)
1457 				goto out; /* no sources allowed */
1458 
1459 			mld_gq_start_work(idev);
1460 			goto out;
1461 		}
1462 		/* mark sources to include, if group & source-specific */
1463 		if (mlh2->mld2q_nsrcs != 0) {
1464 			if (!pskb_may_pull(skb, srcs_offset +
1465 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1466 				goto out;
1467 
1468 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1469 			mark = 1;
1470 		}
1471 	} else {
1472 		goto out;
1473 	}
1474 
1475 	if (group_type == IPV6_ADDR_ANY) {
1476 		for_each_mc_mclock(idev, ma) {
1477 			igmp6_group_queried(ma, max_delay);
1478 		}
1479 	} else {
1480 		for_each_mc_mclock(idev, ma) {
1481 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1482 				continue;
1483 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1484 				/* gsquery <- gsquery && mark */
1485 				if (!mark)
1486 					ma->mca_flags &= ~MAF_GSQUERY;
1487 			} else {
1488 				/* gsquery <- mark */
1489 				if (mark)
1490 					ma->mca_flags |= MAF_GSQUERY;
1491 				else
1492 					ma->mca_flags &= ~MAF_GSQUERY;
1493 			}
1494 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1495 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1496 				igmp6_group_queried(ma, max_delay);
1497 			break;
1498 		}
1499 	}
1500 
1501 out:
1502 	in6_dev_put(idev);
1503 kfree_skb:
1504 	consume_skb(skb);
1505 }
1506 
mld_query_work(struct work_struct * work)1507 static void mld_query_work(struct work_struct *work)
1508 {
1509 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1510 					      struct inet6_dev,
1511 					      mc_query_work);
1512 	struct sk_buff_head q;
1513 	struct sk_buff *skb;
1514 	bool rework = false;
1515 	int cnt = 0;
1516 
1517 	skb_queue_head_init(&q);
1518 
1519 	spin_lock_bh(&idev->mc_query_lock);
1520 	while ((skb = __skb_dequeue(&idev->mc_query_queue))) {
1521 		__skb_queue_tail(&q, skb);
1522 
1523 		if (++cnt >= MLD_MAX_QUEUE) {
1524 			rework = true;
1525 			break;
1526 		}
1527 	}
1528 	spin_unlock_bh(&idev->mc_query_lock);
1529 
1530 	mutex_lock(&idev->mc_lock);
1531 	while ((skb = __skb_dequeue(&q)))
1532 		__mld_query_work(skb);
1533 	mutex_unlock(&idev->mc_lock);
1534 
1535 	if (rework && queue_delayed_work(mld_wq, &idev->mc_query_work, 0))
1536 		return;
1537 
1538 	in6_dev_put(idev);
1539 }
1540 
1541 /* called with rcu_read_lock() */
igmp6_event_report(struct sk_buff * skb)1542 void igmp6_event_report(struct sk_buff *skb)
1543 {
1544 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1545 
1546 	if (!idev || idev->dead)
1547 		goto out;
1548 
1549 	spin_lock_bh(&idev->mc_report_lock);
1550 	if (skb_queue_len(&idev->mc_report_queue) < MLD_MAX_SKBS) {
1551 		__skb_queue_tail(&idev->mc_report_queue, skb);
1552 		if (!mod_delayed_work(mld_wq, &idev->mc_report_work, 0))
1553 			in6_dev_hold(idev);
1554 		skb = NULL;
1555 	}
1556 	spin_unlock_bh(&idev->mc_report_lock);
1557 out:
1558 	kfree_skb(skb);
1559 }
1560 
__mld_report_work(struct sk_buff * skb)1561 static void __mld_report_work(struct sk_buff *skb)
1562 {
1563 	struct inet6_dev *idev;
1564 	struct ifmcaddr6 *ma;
1565 	struct mld_msg *mld;
1566 	int addr_type;
1567 
1568 	/* Our own report looped back. Ignore it. */
1569 	if (skb->pkt_type == PACKET_LOOPBACK)
1570 		goto kfree_skb;
1571 
1572 	/* send our report if the MC router may not have heard this report */
1573 	if (skb->pkt_type != PACKET_MULTICAST &&
1574 	    skb->pkt_type != PACKET_BROADCAST)
1575 		goto kfree_skb;
1576 
1577 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1578 		goto kfree_skb;
1579 
1580 	mld = (struct mld_msg *)icmp6_hdr(skb);
1581 
1582 	/* Drop reports with not link local source */
1583 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1584 	if (addr_type != IPV6_ADDR_ANY &&
1585 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1586 		goto kfree_skb;
1587 
1588 	idev = in6_dev_get(skb->dev);
1589 	if (!idev)
1590 		goto kfree_skb;
1591 
1592 	/*
1593 	 *	Cancel the work for this group
1594 	 */
1595 
1596 	for_each_mc_mclock(idev, ma) {
1597 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1598 			if (cancel_delayed_work(&ma->mca_work))
1599 				refcount_dec(&ma->mca_refcnt);
1600 			ma->mca_flags &= ~(MAF_LAST_REPORTER |
1601 					   MAF_TIMER_RUNNING);
1602 			break;
1603 		}
1604 	}
1605 
1606 	in6_dev_put(idev);
1607 kfree_skb:
1608 	consume_skb(skb);
1609 }
1610 
mld_report_work(struct work_struct * work)1611 static void mld_report_work(struct work_struct *work)
1612 {
1613 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1614 					      struct inet6_dev,
1615 					      mc_report_work);
1616 	struct sk_buff_head q;
1617 	struct sk_buff *skb;
1618 	bool rework = false;
1619 	int cnt = 0;
1620 
1621 	skb_queue_head_init(&q);
1622 	spin_lock_bh(&idev->mc_report_lock);
1623 	while ((skb = __skb_dequeue(&idev->mc_report_queue))) {
1624 		__skb_queue_tail(&q, skb);
1625 
1626 		if (++cnt >= MLD_MAX_QUEUE) {
1627 			rework = true;
1628 			break;
1629 		}
1630 	}
1631 	spin_unlock_bh(&idev->mc_report_lock);
1632 
1633 	mutex_lock(&idev->mc_lock);
1634 	while ((skb = __skb_dequeue(&q)))
1635 		__mld_report_work(skb);
1636 	mutex_unlock(&idev->mc_lock);
1637 
1638 	if (rework && queue_delayed_work(mld_wq, &idev->mc_report_work, 0))
1639 		return;
1640 
1641 	in6_dev_put(idev);
1642 }
1643 
is_in(struct ifmcaddr6 * pmc,struct ip6_sf_list * psf,int type,int gdeleted,int sdeleted)1644 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1645 		  int gdeleted, int sdeleted)
1646 {
1647 	switch (type) {
1648 	case MLD2_MODE_IS_INCLUDE:
1649 	case MLD2_MODE_IS_EXCLUDE:
1650 		if (gdeleted || sdeleted)
1651 			return false;
1652 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1653 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1654 				return true;
1655 			/* don't include if this source is excluded
1656 			 * in all filters
1657 			 */
1658 			if (psf->sf_count[MCAST_INCLUDE])
1659 				return type == MLD2_MODE_IS_INCLUDE;
1660 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1661 				psf->sf_count[MCAST_EXCLUDE];
1662 		}
1663 		return false;
1664 	case MLD2_CHANGE_TO_INCLUDE:
1665 		if (gdeleted || sdeleted)
1666 			return false;
1667 		return psf->sf_count[MCAST_INCLUDE] != 0;
1668 	case MLD2_CHANGE_TO_EXCLUDE:
1669 		if (gdeleted || sdeleted)
1670 			return false;
1671 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1672 		    psf->sf_count[MCAST_INCLUDE])
1673 			return false;
1674 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1675 			psf->sf_count[MCAST_EXCLUDE];
1676 	case MLD2_ALLOW_NEW_SOURCES:
1677 		if (gdeleted || !psf->sf_crcount)
1678 			return false;
1679 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1680 	case MLD2_BLOCK_OLD_SOURCES:
1681 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1682 			return gdeleted || (psf->sf_crcount && sdeleted);
1683 		return psf->sf_crcount && !gdeleted && !sdeleted;
1684 	}
1685 	return false;
1686 }
1687 
1688 static int
mld_scount(struct ifmcaddr6 * pmc,int type,int gdeleted,int sdeleted)1689 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1690 {
1691 	struct ip6_sf_list *psf;
1692 	int scount = 0;
1693 
1694 	for_each_psf_mclock(pmc, psf) {
1695 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1696 			continue;
1697 		scount++;
1698 	}
1699 	return scount;
1700 }
1701 
ip6_mc_hdr(struct sock * sk,struct sk_buff * skb,struct net_device * dev,const struct in6_addr * saddr,const struct in6_addr * daddr,int proto,int len)1702 static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
1703 		       struct net_device *dev,
1704 		       const struct in6_addr *saddr,
1705 		       const struct in6_addr *daddr,
1706 		       int proto, int len)
1707 {
1708 	struct ipv6hdr *hdr;
1709 
1710 	skb->protocol = htons(ETH_P_IPV6);
1711 	skb->dev = dev;
1712 
1713 	skb_reset_network_header(skb);
1714 	skb_put(skb, sizeof(struct ipv6hdr));
1715 	hdr = ipv6_hdr(skb);
1716 
1717 	ip6_flow_hdr(hdr, 0, 0);
1718 
1719 	hdr->payload_len = htons(len);
1720 	hdr->nexthdr = proto;
1721 	hdr->hop_limit = inet6_sk(sk)->hop_limit;
1722 
1723 	hdr->saddr = *saddr;
1724 	hdr->daddr = *daddr;
1725 }
1726 
mld_newpack(struct inet6_dev * idev,unsigned int mtu)1727 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1728 {
1729 	u8 ra[8] = { IPPROTO_ICMPV6, 0, IPV6_TLV_ROUTERALERT,
1730 		     2, 0, 0, IPV6_TLV_PADN, 0 };
1731 	struct net_device *dev = idev->dev;
1732 	int hlen = LL_RESERVED_SPACE(dev);
1733 	int tlen = dev->needed_tailroom;
1734 	struct net *net = dev_net(dev);
1735 	const struct in6_addr *saddr;
1736 	struct in6_addr addr_buf;
1737 	struct mld2_report *pmr;
1738 	struct sk_buff *skb;
1739 	unsigned int size;
1740 	struct sock *sk;
1741 	int err;
1742 
1743 	sk = net->ipv6.igmp_sk;
1744 	/* we assume size > sizeof(ra) here
1745 	 * Also try to not allocate high-order pages for big MTU
1746 	 */
1747 	size = min_t(int, mtu, PAGE_SIZE / 2) + hlen + tlen;
1748 	skb = sock_alloc_send_skb(sk, size, 1, &err);
1749 	if (!skb)
1750 		return NULL;
1751 
1752 	skb->priority = TC_PRIO_CONTROL;
1753 	skb_reserve(skb, hlen);
1754 	skb_tailroom_reserve(skb, mtu, tlen);
1755 
1756 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
1757 		/* <draft-ietf-magma-mld-source-05.txt>:
1758 		 * use unspecified address as the source address
1759 		 * when a valid link-local address is not available.
1760 		 */
1761 		saddr = &in6addr_any;
1762 	} else
1763 		saddr = &addr_buf;
1764 
1765 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1766 
1767 	skb_put_data(skb, ra, sizeof(ra));
1768 
1769 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1770 	skb_put(skb, sizeof(*pmr));
1771 	pmr = (struct mld2_report *)skb_transport_header(skb);
1772 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1773 	pmr->mld2r_resv1 = 0;
1774 	pmr->mld2r_cksum = 0;
1775 	pmr->mld2r_resv2 = 0;
1776 	pmr->mld2r_ngrec = 0;
1777 	return skb;
1778 }
1779 
mld_sendpack(struct sk_buff * skb)1780 static void mld_sendpack(struct sk_buff *skb)
1781 {
1782 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1783 	struct mld2_report *pmr =
1784 			      (struct mld2_report *)skb_transport_header(skb);
1785 	int payload_len, mldlen;
1786 	struct inet6_dev *idev;
1787 	struct net *net = dev_net(skb->dev);
1788 	int err;
1789 	struct flowi6 fl6;
1790 	struct dst_entry *dst;
1791 
1792 	rcu_read_lock();
1793 	idev = __in6_dev_get(skb->dev);
1794 	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1795 
1796 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1797 		sizeof(*pip6);
1798 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1799 	pip6->payload_len = htons(payload_len);
1800 
1801 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1802 					   IPPROTO_ICMPV6,
1803 					   csum_partial(skb_transport_header(skb),
1804 							mldlen, 0));
1805 
1806 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1807 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1808 			 skb->dev->ifindex);
1809 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1810 
1811 	err = 0;
1812 	if (IS_ERR(dst)) {
1813 		err = PTR_ERR(dst);
1814 		dst = NULL;
1815 	}
1816 	skb_dst_set(skb, dst);
1817 	if (err)
1818 		goto err_out;
1819 
1820 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1821 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1822 		      dst_output);
1823 out:
1824 	if (!err) {
1825 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1826 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1827 	} else {
1828 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1829 	}
1830 
1831 	rcu_read_unlock();
1832 	return;
1833 
1834 err_out:
1835 	kfree_skb(skb);
1836 	goto out;
1837 }
1838 
grec_size(struct ifmcaddr6 * pmc,int type,int gdel,int sdel)1839 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1840 {
1841 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1842 }
1843 
add_grhead(struct sk_buff * skb,struct ifmcaddr6 * pmc,int type,struct mld2_grec ** ppgr,unsigned int mtu)1844 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1845 	int type, struct mld2_grec **ppgr, unsigned int mtu)
1846 {
1847 	struct mld2_report *pmr;
1848 	struct mld2_grec *pgr;
1849 
1850 	if (!skb) {
1851 		skb = mld_newpack(pmc->idev, mtu);
1852 		if (!skb)
1853 			return NULL;
1854 	}
1855 	pgr = skb_put(skb, sizeof(struct mld2_grec));
1856 	pgr->grec_type = type;
1857 	pgr->grec_auxwords = 0;
1858 	pgr->grec_nsrcs = 0;
1859 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1860 	pmr = (struct mld2_report *)skb_transport_header(skb);
1861 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1862 	*ppgr = pgr;
1863 	return skb;
1864 }
1865 
1866 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1867 
1868 /* called with mc_lock */
add_grec(struct sk_buff * skb,struct ifmcaddr6 * pmc,int type,int gdeleted,int sdeleted,int crsend)1869 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1870 				int type, int gdeleted, int sdeleted,
1871 				int crsend)
1872 {
1873 	struct ip6_sf_list *psf, *psf_prev, *psf_next;
1874 	int scount, stotal, first, isquery, truncate;
1875 	struct ip6_sf_list __rcu **psf_list;
1876 	struct inet6_dev *idev = pmc->idev;
1877 	struct net_device *dev = idev->dev;
1878 	struct mld2_grec *pgr = NULL;
1879 	struct mld2_report *pmr;
1880 	unsigned int mtu;
1881 
1882 	if (pmc->mca_flags & MAF_NOREPORT)
1883 		return skb;
1884 
1885 	mtu = READ_ONCE(dev->mtu);
1886 	if (mtu < IPV6_MIN_MTU)
1887 		return skb;
1888 
1889 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1890 		  type == MLD2_MODE_IS_EXCLUDE;
1891 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1892 		    type == MLD2_CHANGE_TO_EXCLUDE;
1893 
1894 	stotal = scount = 0;
1895 
1896 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1897 
1898 	if (!rcu_access_pointer(*psf_list))
1899 		goto empty_source;
1900 
1901 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1902 
1903 	/* EX and TO_EX get a fresh packet, if needed */
1904 	if (truncate) {
1905 		if (pmr && pmr->mld2r_ngrec &&
1906 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1907 			if (skb)
1908 				mld_sendpack(skb);
1909 			skb = mld_newpack(idev, mtu);
1910 		}
1911 	}
1912 	first = 1;
1913 	psf_prev = NULL;
1914 	for (psf = mc_dereference(*psf_list, idev);
1915 	     psf;
1916 	     psf = psf_next) {
1917 		struct in6_addr *psrc;
1918 
1919 		psf_next = mc_dereference(psf->sf_next, idev);
1920 
1921 		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
1922 			psf_prev = psf;
1923 			continue;
1924 		}
1925 
1926 		/* Based on RFC3810 6.1. Should not send source-list change
1927 		 * records when there is a filter mode change.
1928 		 */
1929 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1930 		     (!gdeleted && pmc->mca_crcount)) &&
1931 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1932 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1933 			goto decrease_sf_crcount;
1934 
1935 		/* clear marks on query responses */
1936 		if (isquery)
1937 			psf->sf_gsresp = 0;
1938 
1939 		if (AVAILABLE(skb) < sizeof(*psrc) +
1940 		    first*sizeof(struct mld2_grec)) {
1941 			if (truncate && !first)
1942 				break;	 /* truncate these */
1943 			if (pgr)
1944 				pgr->grec_nsrcs = htons(scount);
1945 			if (skb)
1946 				mld_sendpack(skb);
1947 			skb = mld_newpack(idev, mtu);
1948 			first = 1;
1949 			scount = 0;
1950 		}
1951 		if (first) {
1952 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1953 			first = 0;
1954 		}
1955 		if (!skb)
1956 			return NULL;
1957 		psrc = skb_put(skb, sizeof(*psrc));
1958 		*psrc = psf->sf_addr;
1959 		scount++; stotal++;
1960 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1961 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1962 decrease_sf_crcount:
1963 			psf->sf_crcount--;
1964 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1965 				if (psf_prev)
1966 					rcu_assign_pointer(psf_prev->sf_next,
1967 							   mc_dereference(psf->sf_next, idev));
1968 				else
1969 					rcu_assign_pointer(*psf_list,
1970 							   mc_dereference(psf->sf_next, idev));
1971 				kfree_rcu(psf, rcu);
1972 				continue;
1973 			}
1974 		}
1975 		psf_prev = psf;
1976 	}
1977 
1978 empty_source:
1979 	if (!stotal) {
1980 		if (type == MLD2_ALLOW_NEW_SOURCES ||
1981 		    type == MLD2_BLOCK_OLD_SOURCES)
1982 			return skb;
1983 		if (pmc->mca_crcount || isquery || crsend) {
1984 			/* make sure we have room for group header */
1985 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
1986 				mld_sendpack(skb);
1987 				skb = NULL; /* add_grhead will get a new one */
1988 			}
1989 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1990 		}
1991 	}
1992 	if (pgr)
1993 		pgr->grec_nsrcs = htons(scount);
1994 
1995 	if (isquery)
1996 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
1997 	return skb;
1998 }
1999 
2000 /* called with mc_lock */
mld_send_report(struct inet6_dev * idev,struct ifmcaddr6 * pmc)2001 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
2002 {
2003 	struct sk_buff *skb = NULL;
2004 	int type;
2005 
2006 	if (!pmc) {
2007 		for_each_mc_mclock(idev, pmc) {
2008 			if (pmc->mca_flags & MAF_NOREPORT)
2009 				continue;
2010 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
2011 				type = MLD2_MODE_IS_EXCLUDE;
2012 			else
2013 				type = MLD2_MODE_IS_INCLUDE;
2014 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2015 		}
2016 	} else {
2017 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2018 			type = MLD2_MODE_IS_EXCLUDE;
2019 		else
2020 			type = MLD2_MODE_IS_INCLUDE;
2021 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2022 	}
2023 	if (skb)
2024 		mld_sendpack(skb);
2025 }
2026 
2027 /*
2028  * remove zero-count source records from a source filter list
2029  * called with mc_lock
2030  */
mld_clear_zeros(struct ip6_sf_list __rcu ** ppsf,struct inet6_dev * idev)2031 static void mld_clear_zeros(struct ip6_sf_list __rcu **ppsf, struct inet6_dev *idev)
2032 {
2033 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
2034 
2035 	psf_prev = NULL;
2036 	for (psf = mc_dereference(*ppsf, idev);
2037 	     psf;
2038 	     psf = psf_next) {
2039 		psf_next = mc_dereference(psf->sf_next, idev);
2040 		if (psf->sf_crcount == 0) {
2041 			if (psf_prev)
2042 				rcu_assign_pointer(psf_prev->sf_next,
2043 						   mc_dereference(psf->sf_next, idev));
2044 			else
2045 				rcu_assign_pointer(*ppsf,
2046 						   mc_dereference(psf->sf_next, idev));
2047 			kfree_rcu(psf, rcu);
2048 		} else {
2049 			psf_prev = psf;
2050 		}
2051 	}
2052 }
2053 
2054 /* called with mc_lock */
mld_send_cr(struct inet6_dev * idev)2055 static void mld_send_cr(struct inet6_dev *idev)
2056 {
2057 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
2058 	struct sk_buff *skb = NULL;
2059 	int type, dtype;
2060 
2061 	/* deleted MCA's */
2062 	pmc_prev = NULL;
2063 	for (pmc = mc_dereference(idev->mc_tomb, idev);
2064 	     pmc;
2065 	     pmc = pmc_next) {
2066 		pmc_next = mc_dereference(pmc->next, idev);
2067 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
2068 			type = MLD2_BLOCK_OLD_SOURCES;
2069 			dtype = MLD2_BLOCK_OLD_SOURCES;
2070 			skb = add_grec(skb, pmc, type, 1, 0, 0);
2071 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
2072 		}
2073 		if (pmc->mca_crcount) {
2074 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
2075 				type = MLD2_CHANGE_TO_INCLUDE;
2076 				skb = add_grec(skb, pmc, type, 1, 0, 0);
2077 			}
2078 			pmc->mca_crcount--;
2079 			if (pmc->mca_crcount == 0) {
2080 				mld_clear_zeros(&pmc->mca_tomb, idev);
2081 				mld_clear_zeros(&pmc->mca_sources, idev);
2082 			}
2083 		}
2084 		if (pmc->mca_crcount == 0 &&
2085 		    !rcu_access_pointer(pmc->mca_tomb) &&
2086 		    !rcu_access_pointer(pmc->mca_sources)) {
2087 			if (pmc_prev)
2088 				rcu_assign_pointer(pmc_prev->next, pmc_next);
2089 			else
2090 				rcu_assign_pointer(idev->mc_tomb, pmc_next);
2091 			in6_dev_put(pmc->idev);
2092 			kfree_rcu(pmc, rcu);
2093 		} else
2094 			pmc_prev = pmc;
2095 	}
2096 
2097 	/* change recs */
2098 	for_each_mc_mclock(idev, pmc) {
2099 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2100 			type = MLD2_BLOCK_OLD_SOURCES;
2101 			dtype = MLD2_ALLOW_NEW_SOURCES;
2102 		} else {
2103 			type = MLD2_ALLOW_NEW_SOURCES;
2104 			dtype = MLD2_BLOCK_OLD_SOURCES;
2105 		}
2106 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2107 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
2108 
2109 		/* filter mode changes */
2110 		if (pmc->mca_crcount) {
2111 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
2112 				type = MLD2_CHANGE_TO_EXCLUDE;
2113 			else
2114 				type = MLD2_CHANGE_TO_INCLUDE;
2115 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2116 			pmc->mca_crcount--;
2117 		}
2118 	}
2119 	if (!skb)
2120 		return;
2121 	(void) mld_sendpack(skb);
2122 }
2123 
igmp6_send(struct in6_addr * addr,struct net_device * dev,int type)2124 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
2125 {
2126 	struct net *net = dev_net(dev);
2127 	struct sock *sk = net->ipv6.igmp_sk;
2128 	struct inet6_dev *idev;
2129 	struct sk_buff *skb;
2130 	struct mld_msg *hdr;
2131 	const struct in6_addr *snd_addr, *saddr;
2132 	struct in6_addr addr_buf;
2133 	int hlen = LL_RESERVED_SPACE(dev);
2134 	int tlen = dev->needed_tailroom;
2135 	int err, len, payload_len, full_len;
2136 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
2137 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
2138 		     IPV6_TLV_PADN, 0 };
2139 	struct flowi6 fl6;
2140 	struct dst_entry *dst;
2141 
2142 	if (type == ICMPV6_MGM_REDUCTION)
2143 		snd_addr = &in6addr_linklocal_allrouters;
2144 	else
2145 		snd_addr = addr;
2146 
2147 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
2148 	payload_len = len + sizeof(ra);
2149 	full_len = sizeof(struct ipv6hdr) + payload_len;
2150 
2151 	rcu_read_lock();
2152 	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
2153 		      IPSTATS_MIB_OUT, full_len);
2154 	rcu_read_unlock();
2155 
2156 	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
2157 
2158 	if (!skb) {
2159 		rcu_read_lock();
2160 		IP6_INC_STATS(net, __in6_dev_get(dev),
2161 			      IPSTATS_MIB_OUTDISCARDS);
2162 		rcu_read_unlock();
2163 		return;
2164 	}
2165 	skb->priority = TC_PRIO_CONTROL;
2166 	skb_reserve(skb, hlen);
2167 
2168 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
2169 		/* <draft-ietf-magma-mld-source-05.txt>:
2170 		 * use unspecified address as the source address
2171 		 * when a valid link-local address is not available.
2172 		 */
2173 		saddr = &in6addr_any;
2174 	} else
2175 		saddr = &addr_buf;
2176 
2177 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2178 
2179 	skb_put_data(skb, ra, sizeof(ra));
2180 
2181 	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
2182 	hdr->mld_type = type;
2183 	hdr->mld_mca = *addr;
2184 
2185 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2186 					 IPPROTO_ICMPV6,
2187 					 csum_partial(hdr, len, 0));
2188 
2189 	rcu_read_lock();
2190 	idev = __in6_dev_get(skb->dev);
2191 
2192 	icmpv6_flow_init(sk, &fl6, type,
2193 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2194 			 skb->dev->ifindex);
2195 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2196 	if (IS_ERR(dst)) {
2197 		err = PTR_ERR(dst);
2198 		goto err_out;
2199 	}
2200 
2201 	skb_dst_set(skb, dst);
2202 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2203 		      net, sk, skb, NULL, skb->dev,
2204 		      dst_output);
2205 out:
2206 	if (!err) {
2207 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2208 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2209 	} else
2210 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2211 
2212 	rcu_read_unlock();
2213 	return;
2214 
2215 err_out:
2216 	kfree_skb(skb);
2217 	goto out;
2218 }
2219 
2220 /* called with mc_lock */
mld_send_initial_cr(struct inet6_dev * idev)2221 static void mld_send_initial_cr(struct inet6_dev *idev)
2222 {
2223 	struct sk_buff *skb;
2224 	struct ifmcaddr6 *pmc;
2225 	int type;
2226 
2227 	if (mld_in_v1_mode(idev))
2228 		return;
2229 
2230 	skb = NULL;
2231 	for_each_mc_mclock(idev, pmc) {
2232 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2233 			type = MLD2_CHANGE_TO_EXCLUDE;
2234 		else
2235 			type = MLD2_ALLOW_NEW_SOURCES;
2236 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2237 	}
2238 	if (skb)
2239 		mld_sendpack(skb);
2240 }
2241 
ipv6_mc_dad_complete(struct inet6_dev * idev)2242 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2243 {
2244 	mutex_lock(&idev->mc_lock);
2245 	idev->mc_dad_count = idev->mc_qrv;
2246 	if (idev->mc_dad_count) {
2247 		mld_send_initial_cr(idev);
2248 		idev->mc_dad_count--;
2249 		if (idev->mc_dad_count)
2250 			mld_dad_start_work(idev,
2251 					   unsolicited_report_interval(idev));
2252 	}
2253 	mutex_unlock(&idev->mc_lock);
2254 }
2255 
mld_dad_work(struct work_struct * work)2256 static void mld_dad_work(struct work_struct *work)
2257 {
2258 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2259 					      struct inet6_dev,
2260 					      mc_dad_work);
2261 	mutex_lock(&idev->mc_lock);
2262 	mld_send_initial_cr(idev);
2263 	if (idev->mc_dad_count) {
2264 		idev->mc_dad_count--;
2265 		if (idev->mc_dad_count)
2266 			mld_dad_start_work(idev,
2267 					   unsolicited_report_interval(idev));
2268 	}
2269 	mutex_unlock(&idev->mc_lock);
2270 	in6_dev_put(idev);
2271 }
2272 
2273 /* called with mc_lock */
ip6_mc_del1_src(struct ifmcaddr6 * pmc,int sfmode,const struct in6_addr * psfsrc)2274 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2275 	const struct in6_addr *psfsrc)
2276 {
2277 	struct ip6_sf_list *psf, *psf_prev;
2278 	int rv = 0;
2279 
2280 	psf_prev = NULL;
2281 	for_each_psf_mclock(pmc, psf) {
2282 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2283 			break;
2284 		psf_prev = psf;
2285 	}
2286 	if (!psf || psf->sf_count[sfmode] == 0) {
2287 		/* source filter not found, or count wrong =>  bug */
2288 		return -ESRCH;
2289 	}
2290 	psf->sf_count[sfmode]--;
2291 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2292 		struct inet6_dev *idev = pmc->idev;
2293 
2294 		/* no more filters for this source */
2295 		if (psf_prev)
2296 			rcu_assign_pointer(psf_prev->sf_next,
2297 					   mc_dereference(psf->sf_next, idev));
2298 		else
2299 			rcu_assign_pointer(pmc->mca_sources,
2300 					   mc_dereference(psf->sf_next, idev));
2301 
2302 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2303 		    !mld_in_v1_mode(idev)) {
2304 			psf->sf_crcount = idev->mc_qrv;
2305 			rcu_assign_pointer(psf->sf_next,
2306 					   mc_dereference(pmc->mca_tomb, idev));
2307 			rcu_assign_pointer(pmc->mca_tomb, psf);
2308 			rv = 1;
2309 		} else {
2310 			kfree_rcu(psf, rcu);
2311 		}
2312 	}
2313 	return rv;
2314 }
2315 
2316 /* called with mc_lock */
ip6_mc_del_src(struct inet6_dev * idev,const struct in6_addr * pmca,int sfmode,int sfcount,const struct in6_addr * psfsrc,int delta)2317 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2318 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2319 			  int delta)
2320 {
2321 	struct ifmcaddr6 *pmc;
2322 	int	changerec = 0;
2323 	int	i, err;
2324 
2325 	if (!idev)
2326 		return -ENODEV;
2327 
2328 	for_each_mc_mclock(idev, pmc) {
2329 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2330 			break;
2331 	}
2332 	if (!pmc)
2333 		return -ESRCH;
2334 
2335 	sf_markstate(pmc);
2336 	if (!delta) {
2337 		if (!pmc->mca_sfcount[sfmode])
2338 			return -EINVAL;
2339 
2340 		pmc->mca_sfcount[sfmode]--;
2341 	}
2342 	err = 0;
2343 	for (i = 0; i < sfcount; i++) {
2344 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2345 
2346 		changerec |= rv > 0;
2347 		if (!err && rv < 0)
2348 			err = rv;
2349 	}
2350 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2351 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2352 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2353 		struct ip6_sf_list *psf;
2354 
2355 		/* filter mode change */
2356 		pmc->mca_sfmode = MCAST_INCLUDE;
2357 		pmc->mca_crcount = idev->mc_qrv;
2358 		idev->mc_ifc_count = pmc->mca_crcount;
2359 		for_each_psf_mclock(pmc, psf)
2360 			psf->sf_crcount = 0;
2361 		mld_ifc_event(pmc->idev);
2362 	} else if (sf_setstate(pmc) || changerec) {
2363 		mld_ifc_event(pmc->idev);
2364 	}
2365 
2366 	return err;
2367 }
2368 
2369 /*
2370  * Add multicast single-source filter to the interface list
2371  * called with mc_lock
2372  */
ip6_mc_add1_src(struct ifmcaddr6 * pmc,int sfmode,const struct in6_addr * psfsrc)2373 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2374 	const struct in6_addr *psfsrc)
2375 {
2376 	struct ip6_sf_list *psf, *psf_prev;
2377 
2378 	psf_prev = NULL;
2379 	for_each_psf_mclock(pmc, psf) {
2380 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2381 			break;
2382 		psf_prev = psf;
2383 	}
2384 	if (!psf) {
2385 		psf = kzalloc(sizeof(*psf), GFP_KERNEL);
2386 		if (!psf)
2387 			return -ENOBUFS;
2388 
2389 		psf->sf_addr = *psfsrc;
2390 		if (psf_prev) {
2391 			rcu_assign_pointer(psf_prev->sf_next, psf);
2392 		} else {
2393 			rcu_assign_pointer(pmc->mca_sources, psf);
2394 		}
2395 	}
2396 	psf->sf_count[sfmode]++;
2397 	return 0;
2398 }
2399 
2400 /* called with mc_lock */
sf_markstate(struct ifmcaddr6 * pmc)2401 static void sf_markstate(struct ifmcaddr6 *pmc)
2402 {
2403 	struct ip6_sf_list *psf;
2404 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2405 
2406 	for_each_psf_mclock(pmc, psf) {
2407 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2408 			psf->sf_oldin = mca_xcount ==
2409 				psf->sf_count[MCAST_EXCLUDE] &&
2410 				!psf->sf_count[MCAST_INCLUDE];
2411 		} else {
2412 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2413 		}
2414 	}
2415 }
2416 
2417 /* called with mc_lock */
sf_setstate(struct ifmcaddr6 * pmc)2418 static int sf_setstate(struct ifmcaddr6 *pmc)
2419 {
2420 	struct ip6_sf_list *psf, *dpsf;
2421 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2422 	int qrv = pmc->idev->mc_qrv;
2423 	int new_in, rv;
2424 
2425 	rv = 0;
2426 	for_each_psf_mclock(pmc, psf) {
2427 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2428 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2429 				!psf->sf_count[MCAST_INCLUDE];
2430 		} else
2431 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2432 		if (new_in) {
2433 			if (!psf->sf_oldin) {
2434 				struct ip6_sf_list *prev = NULL;
2435 
2436 				for_each_psf_tomb(pmc, dpsf) {
2437 					if (ipv6_addr_equal(&dpsf->sf_addr,
2438 					    &psf->sf_addr))
2439 						break;
2440 					prev = dpsf;
2441 				}
2442 				if (dpsf) {
2443 					if (prev)
2444 						rcu_assign_pointer(prev->sf_next,
2445 								   mc_dereference(dpsf->sf_next,
2446 										  pmc->idev));
2447 					else
2448 						rcu_assign_pointer(pmc->mca_tomb,
2449 								   mc_dereference(dpsf->sf_next,
2450 										  pmc->idev));
2451 					kfree_rcu(dpsf, rcu);
2452 				}
2453 				psf->sf_crcount = qrv;
2454 				rv++;
2455 			}
2456 		} else if (psf->sf_oldin) {
2457 			psf->sf_crcount = 0;
2458 			/*
2459 			 * add or update "delete" records if an active filter
2460 			 * is now inactive
2461 			 */
2462 
2463 			for_each_psf_tomb(pmc, dpsf)
2464 				if (ipv6_addr_equal(&dpsf->sf_addr,
2465 				    &psf->sf_addr))
2466 					break;
2467 			if (!dpsf) {
2468 				dpsf = kmalloc(sizeof(*dpsf), GFP_KERNEL);
2469 				if (!dpsf)
2470 					continue;
2471 				*dpsf = *psf;
2472 				rcu_assign_pointer(dpsf->sf_next,
2473 						   mc_dereference(pmc->mca_tomb, pmc->idev));
2474 				rcu_assign_pointer(pmc->mca_tomb, dpsf);
2475 			}
2476 			dpsf->sf_crcount = qrv;
2477 			rv++;
2478 		}
2479 	}
2480 	return rv;
2481 }
2482 
2483 /*
2484  * Add multicast source filter list to the interface list
2485  * called with mc_lock
2486  */
ip6_mc_add_src(struct inet6_dev * idev,const struct in6_addr * pmca,int sfmode,int sfcount,const struct in6_addr * psfsrc,int delta)2487 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2488 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2489 			  int delta)
2490 {
2491 	struct ifmcaddr6 *pmc;
2492 	int	isexclude;
2493 	int	i, err;
2494 
2495 	if (!idev)
2496 		return -ENODEV;
2497 
2498 	for_each_mc_mclock(idev, pmc) {
2499 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2500 			break;
2501 	}
2502 	if (!pmc)
2503 		return -ESRCH;
2504 
2505 	sf_markstate(pmc);
2506 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2507 	if (!delta)
2508 		pmc->mca_sfcount[sfmode]++;
2509 	err = 0;
2510 	for (i = 0; i < sfcount; i++) {
2511 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2512 		if (err)
2513 			break;
2514 	}
2515 	if (err) {
2516 		int j;
2517 
2518 		if (!delta)
2519 			pmc->mca_sfcount[sfmode]--;
2520 		for (j = 0; j < i; j++)
2521 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2522 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2523 		struct ip6_sf_list *psf;
2524 
2525 		/* filter mode change */
2526 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2527 			pmc->mca_sfmode = MCAST_EXCLUDE;
2528 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2529 			pmc->mca_sfmode = MCAST_INCLUDE;
2530 		/* else no filters; keep old mode for reports */
2531 
2532 		pmc->mca_crcount = idev->mc_qrv;
2533 		idev->mc_ifc_count = pmc->mca_crcount;
2534 		for_each_psf_mclock(pmc, psf)
2535 			psf->sf_crcount = 0;
2536 		mld_ifc_event(idev);
2537 	} else if (sf_setstate(pmc)) {
2538 		mld_ifc_event(idev);
2539 	}
2540 	return err;
2541 }
2542 
2543 /* called with mc_lock */
ip6_mc_clear_src(struct ifmcaddr6 * pmc)2544 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2545 {
2546 	struct ip6_sf_list *psf, *nextpsf;
2547 
2548 	for (psf = mc_dereference(pmc->mca_tomb, pmc->idev);
2549 	     psf;
2550 	     psf = nextpsf) {
2551 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2552 		kfree_rcu(psf, rcu);
2553 	}
2554 	RCU_INIT_POINTER(pmc->mca_tomb, NULL);
2555 	for (psf = mc_dereference(pmc->mca_sources, pmc->idev);
2556 	     psf;
2557 	     psf = nextpsf) {
2558 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2559 		kfree_rcu(psf, rcu);
2560 	}
2561 	RCU_INIT_POINTER(pmc->mca_sources, NULL);
2562 	pmc->mca_sfmode = MCAST_EXCLUDE;
2563 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2564 	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
2565 }
2566 
2567 /* called with mc_lock */
igmp6_join_group(struct ifmcaddr6 * ma)2568 static void igmp6_join_group(struct ifmcaddr6 *ma)
2569 {
2570 	unsigned long delay;
2571 
2572 	if (ma->mca_flags & MAF_NOREPORT)
2573 		return;
2574 
2575 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2576 
2577 	delay = prandom_u32_max(unsolicited_report_interval(ma->idev));
2578 
2579 	if (cancel_delayed_work(&ma->mca_work)) {
2580 		refcount_dec(&ma->mca_refcnt);
2581 		delay = ma->mca_work.timer.expires - jiffies;
2582 	}
2583 
2584 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
2585 		refcount_inc(&ma->mca_refcnt);
2586 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2587 }
2588 
ip6_mc_leave_src(struct sock * sk,struct ipv6_mc_socklist * iml,struct inet6_dev * idev)2589 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2590 			    struct inet6_dev *idev)
2591 {
2592 	struct ip6_sf_socklist *psl;
2593 	int err;
2594 
2595 	psl = sock_dereference(iml->sflist, sk);
2596 
2597 	if (idev)
2598 		mutex_lock(&idev->mc_lock);
2599 
2600 	if (!psl) {
2601 		/* any-source empty exclude case */
2602 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2603 	} else {
2604 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2605 				     psl->sl_count, psl->sl_addr, 0);
2606 		RCU_INIT_POINTER(iml->sflist, NULL);
2607 		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2608 			   &sk->sk_omem_alloc);
2609 		kfree_rcu(psl, rcu);
2610 	}
2611 
2612 	if (idev)
2613 		mutex_unlock(&idev->mc_lock);
2614 
2615 	return err;
2616 }
2617 
2618 /* called with mc_lock */
igmp6_leave_group(struct ifmcaddr6 * ma)2619 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2620 {
2621 	if (mld_in_v1_mode(ma->idev)) {
2622 		if (ma->mca_flags & MAF_LAST_REPORTER) {
2623 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2624 				ICMPV6_MGM_REDUCTION);
2625 		}
2626 	} else {
2627 		mld_add_delrec(ma->idev, ma);
2628 		mld_ifc_event(ma->idev);
2629 	}
2630 }
2631 
mld_gq_work(struct work_struct * work)2632 static void mld_gq_work(struct work_struct *work)
2633 {
2634 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2635 					      struct inet6_dev,
2636 					      mc_gq_work);
2637 
2638 	mutex_lock(&idev->mc_lock);
2639 	mld_send_report(idev, NULL);
2640 	idev->mc_gq_running = 0;
2641 	mutex_unlock(&idev->mc_lock);
2642 
2643 	in6_dev_put(idev);
2644 }
2645 
mld_ifc_work(struct work_struct * work)2646 static void mld_ifc_work(struct work_struct *work)
2647 {
2648 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2649 					      struct inet6_dev,
2650 					      mc_ifc_work);
2651 
2652 	mutex_lock(&idev->mc_lock);
2653 	mld_send_cr(idev);
2654 
2655 	if (idev->mc_ifc_count) {
2656 		idev->mc_ifc_count--;
2657 		if (idev->mc_ifc_count)
2658 			mld_ifc_start_work(idev,
2659 					   unsolicited_report_interval(idev));
2660 	}
2661 	mutex_unlock(&idev->mc_lock);
2662 	in6_dev_put(idev);
2663 }
2664 
2665 /* called with mc_lock */
mld_ifc_event(struct inet6_dev * idev)2666 static void mld_ifc_event(struct inet6_dev *idev)
2667 {
2668 	if (mld_in_v1_mode(idev))
2669 		return;
2670 
2671 	idev->mc_ifc_count = idev->mc_qrv;
2672 	mld_ifc_start_work(idev, 1);
2673 }
2674 
mld_mca_work(struct work_struct * work)2675 static void mld_mca_work(struct work_struct *work)
2676 {
2677 	struct ifmcaddr6 *ma = container_of(to_delayed_work(work),
2678 					    struct ifmcaddr6, mca_work);
2679 
2680 	mutex_lock(&ma->idev->mc_lock);
2681 	if (mld_in_v1_mode(ma->idev))
2682 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2683 	else
2684 		mld_send_report(ma->idev, ma);
2685 	ma->mca_flags |=  MAF_LAST_REPORTER;
2686 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2687 	mutex_unlock(&ma->idev->mc_lock);
2688 
2689 	ma_put(ma);
2690 }
2691 
2692 /* Device changing type */
2693 
ipv6_mc_unmap(struct inet6_dev * idev)2694 void ipv6_mc_unmap(struct inet6_dev *idev)
2695 {
2696 	struct ifmcaddr6 *i;
2697 
2698 	/* Install multicast list, except for all-nodes (already installed) */
2699 
2700 	mutex_lock(&idev->mc_lock);
2701 	for_each_mc_mclock(idev, i)
2702 		igmp6_group_dropped(i);
2703 	mutex_unlock(&idev->mc_lock);
2704 }
2705 
ipv6_mc_remap(struct inet6_dev * idev)2706 void ipv6_mc_remap(struct inet6_dev *idev)
2707 {
2708 	ipv6_mc_up(idev);
2709 }
2710 
2711 /* Device going down */
ipv6_mc_down(struct inet6_dev * idev)2712 void ipv6_mc_down(struct inet6_dev *idev)
2713 {
2714 	struct ifmcaddr6 *i;
2715 
2716 	mutex_lock(&idev->mc_lock);
2717 	/* Withdraw multicast list */
2718 	for_each_mc_mclock(idev, i)
2719 		igmp6_group_dropped(i);
2720 	mutex_unlock(&idev->mc_lock);
2721 
2722 	/* Should stop work after group drop. or we will
2723 	 * start work again in mld_ifc_event()
2724 	 */
2725 	synchronize_net();
2726 	mld_query_stop_work(idev);
2727 	mld_report_stop_work(idev);
2728 	mld_ifc_stop_work(idev);
2729 	mld_gq_stop_work(idev);
2730 	mld_dad_stop_work(idev);
2731 }
2732 
ipv6_mc_reset(struct inet6_dev * idev)2733 static void ipv6_mc_reset(struct inet6_dev *idev)
2734 {
2735 	idev->mc_qrv = sysctl_mld_qrv;
2736 	idev->mc_qi = MLD_QI_DEFAULT;
2737 	idev->mc_qri = MLD_QRI_DEFAULT;
2738 	idev->mc_v1_seen = 0;
2739 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2740 }
2741 
2742 /* Device going up */
2743 
ipv6_mc_up(struct inet6_dev * idev)2744 void ipv6_mc_up(struct inet6_dev *idev)
2745 {
2746 	struct ifmcaddr6 *i;
2747 
2748 	/* Install multicast list, except for all-nodes (already installed) */
2749 
2750 	ipv6_mc_reset(idev);
2751 	mutex_lock(&idev->mc_lock);
2752 	for_each_mc_mclock(idev, i) {
2753 		mld_del_delrec(idev, i);
2754 		igmp6_group_added(i);
2755 	}
2756 	mutex_unlock(&idev->mc_lock);
2757 }
2758 
2759 /* IPv6 device initialization. */
2760 
ipv6_mc_init_dev(struct inet6_dev * idev)2761 void ipv6_mc_init_dev(struct inet6_dev *idev)
2762 {
2763 	idev->mc_gq_running = 0;
2764 	INIT_DELAYED_WORK(&idev->mc_gq_work, mld_gq_work);
2765 	RCU_INIT_POINTER(idev->mc_tomb, NULL);
2766 	idev->mc_ifc_count = 0;
2767 	INIT_DELAYED_WORK(&idev->mc_ifc_work, mld_ifc_work);
2768 	INIT_DELAYED_WORK(&idev->mc_dad_work, mld_dad_work);
2769 	INIT_DELAYED_WORK(&idev->mc_query_work, mld_query_work);
2770 	INIT_DELAYED_WORK(&idev->mc_report_work, mld_report_work);
2771 	skb_queue_head_init(&idev->mc_query_queue);
2772 	skb_queue_head_init(&idev->mc_report_queue);
2773 	spin_lock_init(&idev->mc_query_lock);
2774 	spin_lock_init(&idev->mc_report_lock);
2775 	mutex_init(&idev->mc_lock);
2776 	ipv6_mc_reset(idev);
2777 }
2778 
2779 /*
2780  *	Device is about to be destroyed: clean up.
2781  */
2782 
ipv6_mc_destroy_dev(struct inet6_dev * idev)2783 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2784 {
2785 	struct ifmcaddr6 *i;
2786 
2787 	/* Deactivate works */
2788 	ipv6_mc_down(idev);
2789 	mutex_lock(&idev->mc_lock);
2790 	mld_clear_delrec(idev);
2791 	mutex_unlock(&idev->mc_lock);
2792 	mld_clear_query(idev);
2793 	mld_clear_report(idev);
2794 
2795 	/* Delete all-nodes address. */
2796 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2797 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2798 	 * fail.
2799 	 */
2800 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2801 
2802 	if (idev->cnf.forwarding)
2803 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2804 
2805 	mutex_lock(&idev->mc_lock);
2806 	while ((i = mc_dereference(idev->mc_list, idev))) {
2807 		rcu_assign_pointer(idev->mc_list, mc_dereference(i->next, idev));
2808 
2809 		ip6_mc_clear_src(i);
2810 		ma_put(i);
2811 	}
2812 	mutex_unlock(&idev->mc_lock);
2813 }
2814 
ipv6_mc_rejoin_groups(struct inet6_dev * idev)2815 static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
2816 {
2817 	struct ifmcaddr6 *pmc;
2818 
2819 	ASSERT_RTNL();
2820 
2821 	mutex_lock(&idev->mc_lock);
2822 	if (mld_in_v1_mode(idev)) {
2823 		for_each_mc_mclock(idev, pmc)
2824 			igmp6_join_group(pmc);
2825 	} else {
2826 		mld_send_report(idev, NULL);
2827 	}
2828 	mutex_unlock(&idev->mc_lock);
2829 }
2830 
ipv6_mc_netdev_event(struct notifier_block * this,unsigned long event,void * ptr)2831 static int ipv6_mc_netdev_event(struct notifier_block *this,
2832 				unsigned long event,
2833 				void *ptr)
2834 {
2835 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2836 	struct inet6_dev *idev = __in6_dev_get(dev);
2837 
2838 	switch (event) {
2839 	case NETDEV_RESEND_IGMP:
2840 		if (idev)
2841 			ipv6_mc_rejoin_groups(idev);
2842 		break;
2843 	default:
2844 		break;
2845 	}
2846 
2847 	return NOTIFY_DONE;
2848 }
2849 
2850 static struct notifier_block igmp6_netdev_notifier = {
2851 	.notifier_call = ipv6_mc_netdev_event,
2852 };
2853 
2854 #ifdef CONFIG_PROC_FS
2855 struct igmp6_mc_iter_state {
2856 	struct seq_net_private p;
2857 	struct net_device *dev;
2858 	struct inet6_dev *idev;
2859 };
2860 
2861 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2862 
igmp6_mc_get_first(struct seq_file * seq)2863 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2864 {
2865 	struct ifmcaddr6 *im = NULL;
2866 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2867 	struct net *net = seq_file_net(seq);
2868 
2869 	state->idev = NULL;
2870 	for_each_netdev_rcu(net, state->dev) {
2871 		struct inet6_dev *idev;
2872 		idev = __in6_dev_get(state->dev);
2873 		if (!idev)
2874 			continue;
2875 
2876 		im = rcu_dereference(idev->mc_list);
2877 		if (im) {
2878 			state->idev = idev;
2879 			break;
2880 		}
2881 	}
2882 	return im;
2883 }
2884 
igmp6_mc_get_next(struct seq_file * seq,struct ifmcaddr6 * im)2885 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2886 {
2887 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2888 
2889 	im = rcu_dereference(im->next);
2890 	while (!im) {
2891 		state->dev = next_net_device_rcu(state->dev);
2892 		if (!state->dev) {
2893 			state->idev = NULL;
2894 			break;
2895 		}
2896 		state->idev = __in6_dev_get(state->dev);
2897 		if (!state->idev)
2898 			continue;
2899 		im = rcu_dereference(state->idev->mc_list);
2900 	}
2901 	return im;
2902 }
2903 
igmp6_mc_get_idx(struct seq_file * seq,loff_t pos)2904 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2905 {
2906 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2907 	if (im)
2908 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2909 			--pos;
2910 	return pos ? NULL : im;
2911 }
2912 
igmp6_mc_seq_start(struct seq_file * seq,loff_t * pos)2913 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2914 	__acquires(RCU)
2915 {
2916 	rcu_read_lock();
2917 	return igmp6_mc_get_idx(seq, *pos);
2918 }
2919 
igmp6_mc_seq_next(struct seq_file * seq,void * v,loff_t * pos)2920 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2921 {
2922 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2923 
2924 	++*pos;
2925 	return im;
2926 }
2927 
igmp6_mc_seq_stop(struct seq_file * seq,void * v)2928 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2929 	__releases(RCU)
2930 {
2931 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2932 
2933 	if (likely(state->idev))
2934 		state->idev = NULL;
2935 	state->dev = NULL;
2936 	rcu_read_unlock();
2937 }
2938 
igmp6_mc_seq_show(struct seq_file * seq,void * v)2939 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2940 {
2941 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2942 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2943 
2944 	seq_printf(seq,
2945 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2946 		   state->dev->ifindex, state->dev->name,
2947 		   &im->mca_addr,
2948 		   im->mca_users, im->mca_flags,
2949 		   (im->mca_flags & MAF_TIMER_RUNNING) ?
2950 		   jiffies_to_clock_t(im->mca_work.timer.expires - jiffies) : 0);
2951 	return 0;
2952 }
2953 
2954 static const struct seq_operations igmp6_mc_seq_ops = {
2955 	.start	=	igmp6_mc_seq_start,
2956 	.next	=	igmp6_mc_seq_next,
2957 	.stop	=	igmp6_mc_seq_stop,
2958 	.show	=	igmp6_mc_seq_show,
2959 };
2960 
2961 struct igmp6_mcf_iter_state {
2962 	struct seq_net_private p;
2963 	struct net_device *dev;
2964 	struct inet6_dev *idev;
2965 	struct ifmcaddr6 *im;
2966 };
2967 
2968 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2969 
igmp6_mcf_get_first(struct seq_file * seq)2970 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
2971 {
2972 	struct ip6_sf_list *psf = NULL;
2973 	struct ifmcaddr6 *im = NULL;
2974 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2975 	struct net *net = seq_file_net(seq);
2976 
2977 	state->idev = NULL;
2978 	state->im = NULL;
2979 	for_each_netdev_rcu(net, state->dev) {
2980 		struct inet6_dev *idev;
2981 		idev = __in6_dev_get(state->dev);
2982 		if (unlikely(idev == NULL))
2983 			continue;
2984 
2985 		im = rcu_dereference(idev->mc_list);
2986 		if (likely(im)) {
2987 			psf = rcu_dereference(im->mca_sources);
2988 			if (likely(psf)) {
2989 				state->im = im;
2990 				state->idev = idev;
2991 				break;
2992 			}
2993 		}
2994 	}
2995 	return psf;
2996 }
2997 
igmp6_mcf_get_next(struct seq_file * seq,struct ip6_sf_list * psf)2998 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
2999 {
3000 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3001 
3002 	psf = rcu_dereference(psf->sf_next);
3003 	while (!psf) {
3004 		state->im = rcu_dereference(state->im->next);
3005 		while (!state->im) {
3006 			state->dev = next_net_device_rcu(state->dev);
3007 			if (!state->dev) {
3008 				state->idev = NULL;
3009 				goto out;
3010 			}
3011 			state->idev = __in6_dev_get(state->dev);
3012 			if (!state->idev)
3013 				continue;
3014 			state->im = rcu_dereference(state->idev->mc_list);
3015 		}
3016 		if (!state->im)
3017 			break;
3018 		psf = rcu_dereference(state->im->mca_sources);
3019 	}
3020 out:
3021 	return psf;
3022 }
3023 
igmp6_mcf_get_idx(struct seq_file * seq,loff_t pos)3024 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
3025 {
3026 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
3027 	if (psf)
3028 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
3029 			--pos;
3030 	return pos ? NULL : psf;
3031 }
3032 
igmp6_mcf_seq_start(struct seq_file * seq,loff_t * pos)3033 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
3034 	__acquires(RCU)
3035 {
3036 	rcu_read_lock();
3037 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
3038 }
3039 
igmp6_mcf_seq_next(struct seq_file * seq,void * v,loff_t * pos)3040 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3041 {
3042 	struct ip6_sf_list *psf;
3043 	if (v == SEQ_START_TOKEN)
3044 		psf = igmp6_mcf_get_first(seq);
3045 	else
3046 		psf = igmp6_mcf_get_next(seq, v);
3047 	++*pos;
3048 	return psf;
3049 }
3050 
igmp6_mcf_seq_stop(struct seq_file * seq,void * v)3051 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
3052 	__releases(RCU)
3053 {
3054 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3055 
3056 	if (likely(state->im))
3057 		state->im = NULL;
3058 	if (likely(state->idev))
3059 		state->idev = NULL;
3060 
3061 	state->dev = NULL;
3062 	rcu_read_unlock();
3063 }
3064 
igmp6_mcf_seq_show(struct seq_file * seq,void * v)3065 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
3066 {
3067 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
3068 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3069 
3070 	if (v == SEQ_START_TOKEN) {
3071 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
3072 	} else {
3073 		seq_printf(seq,
3074 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
3075 			   state->dev->ifindex, state->dev->name,
3076 			   &state->im->mca_addr,
3077 			   &psf->sf_addr,
3078 			   psf->sf_count[MCAST_INCLUDE],
3079 			   psf->sf_count[MCAST_EXCLUDE]);
3080 	}
3081 	return 0;
3082 }
3083 
3084 static const struct seq_operations igmp6_mcf_seq_ops = {
3085 	.start	=	igmp6_mcf_seq_start,
3086 	.next	=	igmp6_mcf_seq_next,
3087 	.stop	=	igmp6_mcf_seq_stop,
3088 	.show	=	igmp6_mcf_seq_show,
3089 };
3090 
igmp6_proc_init(struct net * net)3091 static int __net_init igmp6_proc_init(struct net *net)
3092 {
3093 	int err;
3094 
3095 	err = -ENOMEM;
3096 	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
3097 			sizeof(struct igmp6_mc_iter_state)))
3098 		goto out;
3099 	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
3100 			&igmp6_mcf_seq_ops,
3101 			sizeof(struct igmp6_mcf_iter_state)))
3102 		goto out_proc_net_igmp6;
3103 
3104 	err = 0;
3105 out:
3106 	return err;
3107 
3108 out_proc_net_igmp6:
3109 	remove_proc_entry("igmp6", net->proc_net);
3110 	goto out;
3111 }
3112 
igmp6_proc_exit(struct net * net)3113 static void __net_exit igmp6_proc_exit(struct net *net)
3114 {
3115 	remove_proc_entry("mcfilter6", net->proc_net);
3116 	remove_proc_entry("igmp6", net->proc_net);
3117 }
3118 #else
igmp6_proc_init(struct net * net)3119 static inline int igmp6_proc_init(struct net *net)
3120 {
3121 	return 0;
3122 }
igmp6_proc_exit(struct net * net)3123 static inline void igmp6_proc_exit(struct net *net)
3124 {
3125 }
3126 #endif
3127 
igmp6_net_init(struct net * net)3128 static int __net_init igmp6_net_init(struct net *net)
3129 {
3130 	int err;
3131 
3132 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
3133 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3134 	if (err < 0) {
3135 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
3136 		       err);
3137 		goto out;
3138 	}
3139 
3140 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
3141 	net->ipv6.igmp_sk->sk_allocation = GFP_KERNEL;
3142 
3143 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
3144 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3145 	if (err < 0) {
3146 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
3147 		       err);
3148 		goto out_sock_create;
3149 	}
3150 
3151 	err = igmp6_proc_init(net);
3152 	if (err)
3153 		goto out_sock_create_autojoin;
3154 
3155 	return 0;
3156 
3157 out_sock_create_autojoin:
3158 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3159 out_sock_create:
3160 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3161 out:
3162 	return err;
3163 }
3164 
igmp6_net_exit(struct net * net)3165 static void __net_exit igmp6_net_exit(struct net *net)
3166 {
3167 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3168 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3169 	igmp6_proc_exit(net);
3170 }
3171 
3172 static struct pernet_operations igmp6_net_ops = {
3173 	.init = igmp6_net_init,
3174 	.exit = igmp6_net_exit,
3175 };
3176 
igmp6_init(void)3177 int __init igmp6_init(void)
3178 {
3179 	int err;
3180 
3181 	err = register_pernet_subsys(&igmp6_net_ops);
3182 	if (err)
3183 		return err;
3184 
3185 	mld_wq = create_workqueue("mld");
3186 	if (!mld_wq) {
3187 		unregister_pernet_subsys(&igmp6_net_ops);
3188 		return -ENOMEM;
3189 	}
3190 
3191 	return err;
3192 }
3193 
igmp6_late_init(void)3194 int __init igmp6_late_init(void)
3195 {
3196 	return register_netdevice_notifier(&igmp6_netdev_notifier);
3197 }
3198 
igmp6_cleanup(void)3199 void igmp6_cleanup(void)
3200 {
3201 	unregister_pernet_subsys(&igmp6_net_ops);
3202 	destroy_workqueue(mld_wq);
3203 }
3204 
igmp6_late_cleanup(void)3205 void igmp6_late_cleanup(void)
3206 {
3207 	unregister_netdevice_notifier(&igmp6_netdev_notifier);
3208 }
3209