xref: /linux/net/ipv6/ip6mr.c (revision d195c39052d1da278a00a6744ce59c383b67b191)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Linux IPv6 multicast routing support for BSD pim6sd
4  *	Based on net/ipv4/ipmr.c.
5  *
6  *	(c) 2004 Mickael Hoerdt, <hoerdt@clarinet.u-strasbg.fr>
7  *		LSIIT Laboratory, Strasbourg, France
8  *	(c) 2004 Jean-Philippe Andriot, <jean-philippe.andriot@6WIND.com>
9  *		6WIND, Paris, France
10  *	Copyright (C)2007,2008 USAGI/WIDE Project
11  *		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
12  */
13 
14 #include <linux/uaccess.h>
15 #include <linux/types.h>
16 #include <linux/sched.h>
17 #include <linux/errno.h>
18 #include <linux/mm.h>
19 #include <linux/kernel.h>
20 #include <linux/fcntl.h>
21 #include <linux/stat.h>
22 #include <linux/socket.h>
23 #include <linux/inet.h>
24 #include <linux/netdevice.h>
25 #include <linux/inetdevice.h>
26 #include <linux/proc_fs.h>
27 #include <linux/seq_file.h>
28 #include <linux/init.h>
29 #include <linux/compat.h>
30 #include <linux/rhashtable.h>
31 #include <net/protocol.h>
32 #include <linux/skbuff.h>
33 #include <net/raw.h>
34 #include <linux/notifier.h>
35 #include <linux/if_arp.h>
36 #include <net/checksum.h>
37 #include <net/netlink.h>
38 #include <net/fib_rules.h>
39 
40 #include <net/ipv6.h>
41 #include <net/ip6_route.h>
42 #include <linux/mroute6.h>
43 #include <linux/pim.h>
44 #include <net/addrconf.h>
45 #include <linux/netfilter_ipv6.h>
46 #include <linux/export.h>
47 #include <net/ip6_checksum.h>
48 #include <linux/netconf.h>
49 #include <net/ip_tunnels.h>
50 
51 #include <linux/nospec.h>
52 
53 struct ip6mr_rule {
54 	struct fib_rule		common;
55 };
56 
57 struct ip6mr_result {
58 	struct mr_table	*mrt;
59 };
60 
61 /* Big lock, protecting vif table, mrt cache and mroute socket state.
62    Note that the changes are semaphored via rtnl_lock.
63  */
64 
65 static DEFINE_RWLOCK(mrt_lock);
66 
67 /* Multicast router control variables */
68 
69 /* Special spinlock for queue of unresolved entries */
70 static DEFINE_SPINLOCK(mfc_unres_lock);
71 
72 /* We return to original Alan's scheme. Hash table of resolved
73    entries is changed only in process context and protected
74    with weak lock mrt_lock. Queue of unresolved entries is protected
75    with strong spinlock mfc_unres_lock.
76 
77    In this case data path is free of exclusive locks at all.
78  */
79 
80 static struct kmem_cache *mrt_cachep __read_mostly;
81 
82 static struct mr_table *ip6mr_new_table(struct net *net, u32 id);
83 static void ip6mr_free_table(struct mr_table *mrt);
84 
85 static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
86 			   struct net_device *dev, struct sk_buff *skb,
87 			   struct mfc6_cache *cache);
88 static int ip6mr_cache_report(struct mr_table *mrt, struct sk_buff *pkt,
89 			      mifi_t mifi, int assert);
90 static void mr6_netlink_event(struct mr_table *mrt, struct mfc6_cache *mfc,
91 			      int cmd);
92 static void mrt6msg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
93 static int ip6mr_rtm_dumproute(struct sk_buff *skb,
94 			       struct netlink_callback *cb);
95 static void mroute_clean_tables(struct mr_table *mrt, int flags);
96 static void ipmr_expire_process(struct timer_list *t);
97 
98 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
99 #define ip6mr_for_each_table(mrt, net) \
100 	list_for_each_entry_rcu(mrt, &net->ipv6.mr6_tables, list, \
101 				lockdep_rtnl_is_held())
102 
103 static struct mr_table *ip6mr_mr_table_iter(struct net *net,
104 					    struct mr_table *mrt)
105 {
106 	struct mr_table *ret;
107 
108 	if (!mrt)
109 		ret = list_entry_rcu(net->ipv6.mr6_tables.next,
110 				     struct mr_table, list);
111 	else
112 		ret = list_entry_rcu(mrt->list.next,
113 				     struct mr_table, list);
114 
115 	if (&ret->list == &net->ipv6.mr6_tables)
116 		return NULL;
117 	return ret;
118 }
119 
120 static struct mr_table *ip6mr_get_table(struct net *net, u32 id)
121 {
122 	struct mr_table *mrt;
123 
124 	ip6mr_for_each_table(mrt, net) {
125 		if (mrt->id == id)
126 			return mrt;
127 	}
128 	return NULL;
129 }
130 
131 static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
132 			    struct mr_table **mrt)
133 {
134 	int err;
135 	struct ip6mr_result res;
136 	struct fib_lookup_arg arg = {
137 		.result = &res,
138 		.flags = FIB_LOOKUP_NOREF,
139 	};
140 
141 	/* update flow if oif or iif point to device enslaved to l3mdev */
142 	l3mdev_update_flow(net, flowi6_to_flowi(flp6));
143 
144 	err = fib_rules_lookup(net->ipv6.mr6_rules_ops,
145 			       flowi6_to_flowi(flp6), 0, &arg);
146 	if (err < 0)
147 		return err;
148 	*mrt = res.mrt;
149 	return 0;
150 }
151 
152 static int ip6mr_rule_action(struct fib_rule *rule, struct flowi *flp,
153 			     int flags, struct fib_lookup_arg *arg)
154 {
155 	struct ip6mr_result *res = arg->result;
156 	struct mr_table *mrt;
157 
158 	switch (rule->action) {
159 	case FR_ACT_TO_TBL:
160 		break;
161 	case FR_ACT_UNREACHABLE:
162 		return -ENETUNREACH;
163 	case FR_ACT_PROHIBIT:
164 		return -EACCES;
165 	case FR_ACT_BLACKHOLE:
166 	default:
167 		return -EINVAL;
168 	}
169 
170 	arg->table = fib_rule_get_table(rule, arg);
171 
172 	mrt = ip6mr_get_table(rule->fr_net, arg->table);
173 	if (!mrt)
174 		return -EAGAIN;
175 	res->mrt = mrt;
176 	return 0;
177 }
178 
179 static int ip6mr_rule_match(struct fib_rule *rule, struct flowi *flp, int flags)
180 {
181 	return 1;
182 }
183 
184 static const struct nla_policy ip6mr_rule_policy[FRA_MAX + 1] = {
185 	FRA_GENERIC_POLICY,
186 };
187 
188 static int ip6mr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
189 				struct fib_rule_hdr *frh, struct nlattr **tb,
190 				struct netlink_ext_ack *extack)
191 {
192 	return 0;
193 }
194 
195 static int ip6mr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
196 			      struct nlattr **tb)
197 {
198 	return 1;
199 }
200 
201 static int ip6mr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
202 			   struct fib_rule_hdr *frh)
203 {
204 	frh->dst_len = 0;
205 	frh->src_len = 0;
206 	frh->tos     = 0;
207 	return 0;
208 }
209 
210 static const struct fib_rules_ops __net_initconst ip6mr_rules_ops_template = {
211 	.family		= RTNL_FAMILY_IP6MR,
212 	.rule_size	= sizeof(struct ip6mr_rule),
213 	.addr_size	= sizeof(struct in6_addr),
214 	.action		= ip6mr_rule_action,
215 	.match		= ip6mr_rule_match,
216 	.configure	= ip6mr_rule_configure,
217 	.compare	= ip6mr_rule_compare,
218 	.fill		= ip6mr_rule_fill,
219 	.nlgroup	= RTNLGRP_IPV6_RULE,
220 	.policy		= ip6mr_rule_policy,
221 	.owner		= THIS_MODULE,
222 };
223 
224 static int __net_init ip6mr_rules_init(struct net *net)
225 {
226 	struct fib_rules_ops *ops;
227 	struct mr_table *mrt;
228 	int err;
229 
230 	ops = fib_rules_register(&ip6mr_rules_ops_template, net);
231 	if (IS_ERR(ops))
232 		return PTR_ERR(ops);
233 
234 	INIT_LIST_HEAD(&net->ipv6.mr6_tables);
235 
236 	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
237 	if (IS_ERR(mrt)) {
238 		err = PTR_ERR(mrt);
239 		goto err1;
240 	}
241 
242 	err = fib_default_rule_add(ops, 0x7fff, RT6_TABLE_DFLT, 0);
243 	if (err < 0)
244 		goto err2;
245 
246 	net->ipv6.mr6_rules_ops = ops;
247 	return 0;
248 
249 err2:
250 	ip6mr_free_table(mrt);
251 err1:
252 	fib_rules_unregister(ops);
253 	return err;
254 }
255 
256 static void __net_exit ip6mr_rules_exit(struct net *net)
257 {
258 	struct mr_table *mrt, *next;
259 
260 	rtnl_lock();
261 	list_for_each_entry_safe(mrt, next, &net->ipv6.mr6_tables, list) {
262 		list_del(&mrt->list);
263 		ip6mr_free_table(mrt);
264 	}
265 	fib_rules_unregister(net->ipv6.mr6_rules_ops);
266 	rtnl_unlock();
267 }
268 
269 static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
270 			    struct netlink_ext_ack *extack)
271 {
272 	return fib_rules_dump(net, nb, RTNL_FAMILY_IP6MR, extack);
273 }
274 
275 static unsigned int ip6mr_rules_seq_read(struct net *net)
276 {
277 	return fib_rules_seq_read(net, RTNL_FAMILY_IP6MR);
278 }
279 
280 bool ip6mr_rule_default(const struct fib_rule *rule)
281 {
282 	return fib_rule_matchall(rule) && rule->action == FR_ACT_TO_TBL &&
283 	       rule->table == RT6_TABLE_DFLT && !rule->l3mdev;
284 }
285 EXPORT_SYMBOL(ip6mr_rule_default);
286 #else
287 #define ip6mr_for_each_table(mrt, net) \
288 	for (mrt = net->ipv6.mrt6; mrt; mrt = NULL)
289 
290 static struct mr_table *ip6mr_mr_table_iter(struct net *net,
291 					    struct mr_table *mrt)
292 {
293 	if (!mrt)
294 		return net->ipv6.mrt6;
295 	return NULL;
296 }
297 
298 static struct mr_table *ip6mr_get_table(struct net *net, u32 id)
299 {
300 	return net->ipv6.mrt6;
301 }
302 
303 static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
304 			    struct mr_table **mrt)
305 {
306 	*mrt = net->ipv6.mrt6;
307 	return 0;
308 }
309 
310 static int __net_init ip6mr_rules_init(struct net *net)
311 {
312 	struct mr_table *mrt;
313 
314 	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
315 	if (IS_ERR(mrt))
316 		return PTR_ERR(mrt);
317 	net->ipv6.mrt6 = mrt;
318 	return 0;
319 }
320 
321 static void __net_exit ip6mr_rules_exit(struct net *net)
322 {
323 	rtnl_lock();
324 	ip6mr_free_table(net->ipv6.mrt6);
325 	net->ipv6.mrt6 = NULL;
326 	rtnl_unlock();
327 }
328 
329 static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
330 			    struct netlink_ext_ack *extack)
331 {
332 	return 0;
333 }
334 
335 static unsigned int ip6mr_rules_seq_read(struct net *net)
336 {
337 	return 0;
338 }
339 #endif
340 
341 static int ip6mr_hash_cmp(struct rhashtable_compare_arg *arg,
342 			  const void *ptr)
343 {
344 	const struct mfc6_cache_cmp_arg *cmparg = arg->key;
345 	struct mfc6_cache *c = (struct mfc6_cache *)ptr;
346 
347 	return !ipv6_addr_equal(&c->mf6c_mcastgrp, &cmparg->mf6c_mcastgrp) ||
348 	       !ipv6_addr_equal(&c->mf6c_origin, &cmparg->mf6c_origin);
349 }
350 
351 static const struct rhashtable_params ip6mr_rht_params = {
352 	.head_offset = offsetof(struct mr_mfc, mnode),
353 	.key_offset = offsetof(struct mfc6_cache, cmparg),
354 	.key_len = sizeof(struct mfc6_cache_cmp_arg),
355 	.nelem_hint = 3,
356 	.obj_cmpfn = ip6mr_hash_cmp,
357 	.automatic_shrinking = true,
358 };
359 
360 static void ip6mr_new_table_set(struct mr_table *mrt,
361 				struct net *net)
362 {
363 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
364 	list_add_tail_rcu(&mrt->list, &net->ipv6.mr6_tables);
365 #endif
366 }
367 
368 static struct mfc6_cache_cmp_arg ip6mr_mr_table_ops_cmparg_any = {
369 	.mf6c_origin = IN6ADDR_ANY_INIT,
370 	.mf6c_mcastgrp = IN6ADDR_ANY_INIT,
371 };
372 
373 static struct mr_table_ops ip6mr_mr_table_ops = {
374 	.rht_params = &ip6mr_rht_params,
375 	.cmparg_any = &ip6mr_mr_table_ops_cmparg_any,
376 };
377 
378 static struct mr_table *ip6mr_new_table(struct net *net, u32 id)
379 {
380 	struct mr_table *mrt;
381 
382 	mrt = ip6mr_get_table(net, id);
383 	if (mrt)
384 		return mrt;
385 
386 	return mr_table_alloc(net, id, &ip6mr_mr_table_ops,
387 			      ipmr_expire_process, ip6mr_new_table_set);
388 }
389 
390 static void ip6mr_free_table(struct mr_table *mrt)
391 {
392 	del_timer_sync(&mrt->ipmr_expire_timer);
393 	mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC |
394 				 MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC);
395 	rhltable_destroy(&mrt->mfc_hash);
396 	kfree(mrt);
397 }
398 
399 #ifdef CONFIG_PROC_FS
400 /* The /proc interfaces to multicast routing
401  * /proc/ip6_mr_cache /proc/ip6_mr_vif
402  */
403 
404 static void *ip6mr_vif_seq_start(struct seq_file *seq, loff_t *pos)
405 	__acquires(mrt_lock)
406 {
407 	struct mr_vif_iter *iter = seq->private;
408 	struct net *net = seq_file_net(seq);
409 	struct mr_table *mrt;
410 
411 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
412 	if (!mrt)
413 		return ERR_PTR(-ENOENT);
414 
415 	iter->mrt = mrt;
416 
417 	read_lock(&mrt_lock);
418 	return mr_vif_seq_start(seq, pos);
419 }
420 
421 static void ip6mr_vif_seq_stop(struct seq_file *seq, void *v)
422 	__releases(mrt_lock)
423 {
424 	read_unlock(&mrt_lock);
425 }
426 
427 static int ip6mr_vif_seq_show(struct seq_file *seq, void *v)
428 {
429 	struct mr_vif_iter *iter = seq->private;
430 	struct mr_table *mrt = iter->mrt;
431 
432 	if (v == SEQ_START_TOKEN) {
433 		seq_puts(seq,
434 			 "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags\n");
435 	} else {
436 		const struct vif_device *vif = v;
437 		const char *name = vif->dev ? vif->dev->name : "none";
438 
439 		seq_printf(seq,
440 			   "%2td %-10s %8ld %7ld  %8ld %7ld %05X\n",
441 			   vif - mrt->vif_table,
442 			   name, vif->bytes_in, vif->pkt_in,
443 			   vif->bytes_out, vif->pkt_out,
444 			   vif->flags);
445 	}
446 	return 0;
447 }
448 
449 static const struct seq_operations ip6mr_vif_seq_ops = {
450 	.start = ip6mr_vif_seq_start,
451 	.next  = mr_vif_seq_next,
452 	.stop  = ip6mr_vif_seq_stop,
453 	.show  = ip6mr_vif_seq_show,
454 };
455 
456 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
457 {
458 	struct net *net = seq_file_net(seq);
459 	struct mr_table *mrt;
460 
461 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
462 	if (!mrt)
463 		return ERR_PTR(-ENOENT);
464 
465 	return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
466 }
467 
468 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
469 {
470 	int n;
471 
472 	if (v == SEQ_START_TOKEN) {
473 		seq_puts(seq,
474 			 "Group                            "
475 			 "Origin                           "
476 			 "Iif      Pkts  Bytes     Wrong  Oifs\n");
477 	} else {
478 		const struct mfc6_cache *mfc = v;
479 		const struct mr_mfc_iter *it = seq->private;
480 		struct mr_table *mrt = it->mrt;
481 
482 		seq_printf(seq, "%pI6 %pI6 %-3hd",
483 			   &mfc->mf6c_mcastgrp, &mfc->mf6c_origin,
484 			   mfc->_c.mfc_parent);
485 
486 		if (it->cache != &mrt->mfc_unres_queue) {
487 			seq_printf(seq, " %8lu %8lu %8lu",
488 				   mfc->_c.mfc_un.res.pkt,
489 				   mfc->_c.mfc_un.res.bytes,
490 				   mfc->_c.mfc_un.res.wrong_if);
491 			for (n = mfc->_c.mfc_un.res.minvif;
492 			     n < mfc->_c.mfc_un.res.maxvif; n++) {
493 				if (VIF_EXISTS(mrt, n) &&
494 				    mfc->_c.mfc_un.res.ttls[n] < 255)
495 					seq_printf(seq,
496 						   " %2d:%-3d", n,
497 						   mfc->_c.mfc_un.res.ttls[n]);
498 			}
499 		} else {
500 			/* unresolved mfc_caches don't contain
501 			 * pkt, bytes and wrong_if values
502 			 */
503 			seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
504 		}
505 		seq_putc(seq, '\n');
506 	}
507 	return 0;
508 }
509 
510 static const struct seq_operations ipmr_mfc_seq_ops = {
511 	.start = ipmr_mfc_seq_start,
512 	.next  = mr_mfc_seq_next,
513 	.stop  = mr_mfc_seq_stop,
514 	.show  = ipmr_mfc_seq_show,
515 };
516 #endif
517 
518 #ifdef CONFIG_IPV6_PIMSM_V2
519 
520 static int pim6_rcv(struct sk_buff *skb)
521 {
522 	struct pimreghdr *pim;
523 	struct ipv6hdr   *encap;
524 	struct net_device  *reg_dev = NULL;
525 	struct net *net = dev_net(skb->dev);
526 	struct mr_table *mrt;
527 	struct flowi6 fl6 = {
528 		.flowi6_iif	= skb->dev->ifindex,
529 		.flowi6_mark	= skb->mark,
530 	};
531 	int reg_vif_num;
532 
533 	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
534 		goto drop;
535 
536 	pim = (struct pimreghdr *)skb_transport_header(skb);
537 	if (pim->type != ((PIM_VERSION << 4) | PIM_TYPE_REGISTER) ||
538 	    (pim->flags & PIM_NULL_REGISTER) ||
539 	    (csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
540 			     sizeof(*pim), IPPROTO_PIM,
541 			     csum_partial((void *)pim, sizeof(*pim), 0)) &&
542 	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
543 		goto drop;
544 
545 	/* check if the inner packet is destined to mcast group */
546 	encap = (struct ipv6hdr *)(skb_transport_header(skb) +
547 				   sizeof(*pim));
548 
549 	if (!ipv6_addr_is_multicast(&encap->daddr) ||
550 	    encap->payload_len == 0 ||
551 	    ntohs(encap->payload_len) + sizeof(*pim) > skb->len)
552 		goto drop;
553 
554 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
555 		goto drop;
556 	reg_vif_num = mrt->mroute_reg_vif_num;
557 
558 	read_lock(&mrt_lock);
559 	if (reg_vif_num >= 0)
560 		reg_dev = mrt->vif_table[reg_vif_num].dev;
561 	if (reg_dev)
562 		dev_hold(reg_dev);
563 	read_unlock(&mrt_lock);
564 
565 	if (!reg_dev)
566 		goto drop;
567 
568 	skb->mac_header = skb->network_header;
569 	skb_pull(skb, (u8 *)encap - skb->data);
570 	skb_reset_network_header(skb);
571 	skb->protocol = htons(ETH_P_IPV6);
572 	skb->ip_summed = CHECKSUM_NONE;
573 
574 	skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
575 
576 	netif_rx(skb);
577 
578 	dev_put(reg_dev);
579 	return 0;
580  drop:
581 	kfree_skb(skb);
582 	return 0;
583 }
584 
585 static const struct inet6_protocol pim6_protocol = {
586 	.handler	=	pim6_rcv,
587 };
588 
589 /* Service routines creating virtual interfaces: PIMREG */
590 
591 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb,
592 				      struct net_device *dev)
593 {
594 	struct net *net = dev_net(dev);
595 	struct mr_table *mrt;
596 	struct flowi6 fl6 = {
597 		.flowi6_oif	= dev->ifindex,
598 		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
599 		.flowi6_mark	= skb->mark,
600 	};
601 
602 	if (!pskb_inet_may_pull(skb))
603 		goto tx_err;
604 
605 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
606 		goto tx_err;
607 
608 	read_lock(&mrt_lock);
609 	dev->stats.tx_bytes += skb->len;
610 	dev->stats.tx_packets++;
611 	ip6mr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, MRT6MSG_WHOLEPKT);
612 	read_unlock(&mrt_lock);
613 	kfree_skb(skb);
614 	return NETDEV_TX_OK;
615 
616 tx_err:
617 	dev->stats.tx_errors++;
618 	kfree_skb(skb);
619 	return NETDEV_TX_OK;
620 }
621 
622 static int reg_vif_get_iflink(const struct net_device *dev)
623 {
624 	return 0;
625 }
626 
627 static const struct net_device_ops reg_vif_netdev_ops = {
628 	.ndo_start_xmit	= reg_vif_xmit,
629 	.ndo_get_iflink = reg_vif_get_iflink,
630 };
631 
632 static void reg_vif_setup(struct net_device *dev)
633 {
634 	dev->type		= ARPHRD_PIMREG;
635 	dev->mtu		= 1500 - sizeof(struct ipv6hdr) - 8;
636 	dev->flags		= IFF_NOARP;
637 	dev->netdev_ops		= &reg_vif_netdev_ops;
638 	dev->needs_free_netdev	= true;
639 	dev->features		|= NETIF_F_NETNS_LOCAL;
640 }
641 
642 static struct net_device *ip6mr_reg_vif(struct net *net, struct mr_table *mrt)
643 {
644 	struct net_device *dev;
645 	char name[IFNAMSIZ];
646 
647 	if (mrt->id == RT6_TABLE_DFLT)
648 		sprintf(name, "pim6reg");
649 	else
650 		sprintf(name, "pim6reg%u", mrt->id);
651 
652 	dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
653 	if (!dev)
654 		return NULL;
655 
656 	dev_net_set(dev, net);
657 
658 	if (register_netdevice(dev)) {
659 		free_netdev(dev);
660 		return NULL;
661 	}
662 
663 	if (dev_open(dev, NULL))
664 		goto failure;
665 
666 	dev_hold(dev);
667 	return dev;
668 
669 failure:
670 	unregister_netdevice(dev);
671 	return NULL;
672 }
673 #endif
674 
675 static int call_ip6mr_vif_entry_notifiers(struct net *net,
676 					  enum fib_event_type event_type,
677 					  struct vif_device *vif,
678 					  mifi_t vif_index, u32 tb_id)
679 {
680 	return mr_call_vif_notifiers(net, RTNL_FAMILY_IP6MR, event_type,
681 				     vif, vif_index, tb_id,
682 				     &net->ipv6.ipmr_seq);
683 }
684 
685 static int call_ip6mr_mfc_entry_notifiers(struct net *net,
686 					  enum fib_event_type event_type,
687 					  struct mfc6_cache *mfc, u32 tb_id)
688 {
689 	return mr_call_mfc_notifiers(net, RTNL_FAMILY_IP6MR, event_type,
690 				     &mfc->_c, tb_id, &net->ipv6.ipmr_seq);
691 }
692 
693 /* Delete a VIF entry */
694 static int mif6_delete(struct mr_table *mrt, int vifi, int notify,
695 		       struct list_head *head)
696 {
697 	struct vif_device *v;
698 	struct net_device *dev;
699 	struct inet6_dev *in6_dev;
700 
701 	if (vifi < 0 || vifi >= mrt->maxvif)
702 		return -EADDRNOTAVAIL;
703 
704 	v = &mrt->vif_table[vifi];
705 
706 	if (VIF_EXISTS(mrt, vifi))
707 		call_ip6mr_vif_entry_notifiers(read_pnet(&mrt->net),
708 					       FIB_EVENT_VIF_DEL, v, vifi,
709 					       mrt->id);
710 
711 	write_lock_bh(&mrt_lock);
712 	dev = v->dev;
713 	v->dev = NULL;
714 
715 	if (!dev) {
716 		write_unlock_bh(&mrt_lock);
717 		return -EADDRNOTAVAIL;
718 	}
719 
720 #ifdef CONFIG_IPV6_PIMSM_V2
721 	if (vifi == mrt->mroute_reg_vif_num)
722 		mrt->mroute_reg_vif_num = -1;
723 #endif
724 
725 	if (vifi + 1 == mrt->maxvif) {
726 		int tmp;
727 		for (tmp = vifi - 1; tmp >= 0; tmp--) {
728 			if (VIF_EXISTS(mrt, tmp))
729 				break;
730 		}
731 		mrt->maxvif = tmp + 1;
732 	}
733 
734 	write_unlock_bh(&mrt_lock);
735 
736 	dev_set_allmulti(dev, -1);
737 
738 	in6_dev = __in6_dev_get(dev);
739 	if (in6_dev) {
740 		in6_dev->cnf.mc_forwarding--;
741 		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
742 					     NETCONFA_MC_FORWARDING,
743 					     dev->ifindex, &in6_dev->cnf);
744 	}
745 
746 	if ((v->flags & MIFF_REGISTER) && !notify)
747 		unregister_netdevice_queue(dev, head);
748 
749 	dev_put(dev);
750 	return 0;
751 }
752 
753 static inline void ip6mr_cache_free_rcu(struct rcu_head *head)
754 {
755 	struct mr_mfc *c = container_of(head, struct mr_mfc, rcu);
756 
757 	kmem_cache_free(mrt_cachep, (struct mfc6_cache *)c);
758 }
759 
760 static inline void ip6mr_cache_free(struct mfc6_cache *c)
761 {
762 	call_rcu(&c->_c.rcu, ip6mr_cache_free_rcu);
763 }
764 
765 /* Destroy an unresolved cache entry, killing queued skbs
766    and reporting error to netlink readers.
767  */
768 
769 static void ip6mr_destroy_unres(struct mr_table *mrt, struct mfc6_cache *c)
770 {
771 	struct net *net = read_pnet(&mrt->net);
772 	struct sk_buff *skb;
773 
774 	atomic_dec(&mrt->cache_resolve_queue_len);
775 
776 	while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved)) != NULL) {
777 		if (ipv6_hdr(skb)->version == 0) {
778 			struct nlmsghdr *nlh = skb_pull(skb,
779 							sizeof(struct ipv6hdr));
780 			nlh->nlmsg_type = NLMSG_ERROR;
781 			nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
782 			skb_trim(skb, nlh->nlmsg_len);
783 			((struct nlmsgerr *)nlmsg_data(nlh))->error = -ETIMEDOUT;
784 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
785 		} else
786 			kfree_skb(skb);
787 	}
788 
789 	ip6mr_cache_free(c);
790 }
791 
792 
793 /* Timer process for all the unresolved queue. */
794 
795 static void ipmr_do_expire_process(struct mr_table *mrt)
796 {
797 	unsigned long now = jiffies;
798 	unsigned long expires = 10 * HZ;
799 	struct mr_mfc *c, *next;
800 
801 	list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
802 		if (time_after(c->mfc_un.unres.expires, now)) {
803 			/* not yet... */
804 			unsigned long interval = c->mfc_un.unres.expires - now;
805 			if (interval < expires)
806 				expires = interval;
807 			continue;
808 		}
809 
810 		list_del(&c->list);
811 		mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
812 		ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
813 	}
814 
815 	if (!list_empty(&mrt->mfc_unres_queue))
816 		mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
817 }
818 
819 static void ipmr_expire_process(struct timer_list *t)
820 {
821 	struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
822 
823 	if (!spin_trylock(&mfc_unres_lock)) {
824 		mod_timer(&mrt->ipmr_expire_timer, jiffies + 1);
825 		return;
826 	}
827 
828 	if (!list_empty(&mrt->mfc_unres_queue))
829 		ipmr_do_expire_process(mrt);
830 
831 	spin_unlock(&mfc_unres_lock);
832 }
833 
834 /* Fill oifs list. It is called under write locked mrt_lock. */
835 
836 static void ip6mr_update_thresholds(struct mr_table *mrt,
837 				    struct mr_mfc *cache,
838 				    unsigned char *ttls)
839 {
840 	int vifi;
841 
842 	cache->mfc_un.res.minvif = MAXMIFS;
843 	cache->mfc_un.res.maxvif = 0;
844 	memset(cache->mfc_un.res.ttls, 255, MAXMIFS);
845 
846 	for (vifi = 0; vifi < mrt->maxvif; vifi++) {
847 		if (VIF_EXISTS(mrt, vifi) &&
848 		    ttls[vifi] && ttls[vifi] < 255) {
849 			cache->mfc_un.res.ttls[vifi] = ttls[vifi];
850 			if (cache->mfc_un.res.minvif > vifi)
851 				cache->mfc_un.res.minvif = vifi;
852 			if (cache->mfc_un.res.maxvif <= vifi)
853 				cache->mfc_un.res.maxvif = vifi + 1;
854 		}
855 	}
856 	cache->mfc_un.res.lastuse = jiffies;
857 }
858 
859 static int mif6_add(struct net *net, struct mr_table *mrt,
860 		    struct mif6ctl *vifc, int mrtsock)
861 {
862 	int vifi = vifc->mif6c_mifi;
863 	struct vif_device *v = &mrt->vif_table[vifi];
864 	struct net_device *dev;
865 	struct inet6_dev *in6_dev;
866 	int err;
867 
868 	/* Is vif busy ? */
869 	if (VIF_EXISTS(mrt, vifi))
870 		return -EADDRINUSE;
871 
872 	switch (vifc->mif6c_flags) {
873 #ifdef CONFIG_IPV6_PIMSM_V2
874 	case MIFF_REGISTER:
875 		/*
876 		 * Special Purpose VIF in PIM
877 		 * All the packets will be sent to the daemon
878 		 */
879 		if (mrt->mroute_reg_vif_num >= 0)
880 			return -EADDRINUSE;
881 		dev = ip6mr_reg_vif(net, mrt);
882 		if (!dev)
883 			return -ENOBUFS;
884 		err = dev_set_allmulti(dev, 1);
885 		if (err) {
886 			unregister_netdevice(dev);
887 			dev_put(dev);
888 			return err;
889 		}
890 		break;
891 #endif
892 	case 0:
893 		dev = dev_get_by_index(net, vifc->mif6c_pifi);
894 		if (!dev)
895 			return -EADDRNOTAVAIL;
896 		err = dev_set_allmulti(dev, 1);
897 		if (err) {
898 			dev_put(dev);
899 			return err;
900 		}
901 		break;
902 	default:
903 		return -EINVAL;
904 	}
905 
906 	in6_dev = __in6_dev_get(dev);
907 	if (in6_dev) {
908 		in6_dev->cnf.mc_forwarding++;
909 		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
910 					     NETCONFA_MC_FORWARDING,
911 					     dev->ifindex, &in6_dev->cnf);
912 	}
913 
914 	/* Fill in the VIF structures */
915 	vif_device_init(v, dev, vifc->vifc_rate_limit, vifc->vifc_threshold,
916 			vifc->mif6c_flags | (!mrtsock ? VIFF_STATIC : 0),
917 			MIFF_REGISTER);
918 
919 	/* And finish update writing critical data */
920 	write_lock_bh(&mrt_lock);
921 	v->dev = dev;
922 #ifdef CONFIG_IPV6_PIMSM_V2
923 	if (v->flags & MIFF_REGISTER)
924 		mrt->mroute_reg_vif_num = vifi;
925 #endif
926 	if (vifi + 1 > mrt->maxvif)
927 		mrt->maxvif = vifi + 1;
928 	write_unlock_bh(&mrt_lock);
929 	call_ip6mr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD,
930 				       v, vifi, mrt->id);
931 	return 0;
932 }
933 
934 static struct mfc6_cache *ip6mr_cache_find(struct mr_table *mrt,
935 					   const struct in6_addr *origin,
936 					   const struct in6_addr *mcastgrp)
937 {
938 	struct mfc6_cache_cmp_arg arg = {
939 		.mf6c_origin = *origin,
940 		.mf6c_mcastgrp = *mcastgrp,
941 	};
942 
943 	return mr_mfc_find(mrt, &arg);
944 }
945 
946 /* Look for a (*,G) entry */
947 static struct mfc6_cache *ip6mr_cache_find_any(struct mr_table *mrt,
948 					       struct in6_addr *mcastgrp,
949 					       mifi_t mifi)
950 {
951 	struct mfc6_cache_cmp_arg arg = {
952 		.mf6c_origin = in6addr_any,
953 		.mf6c_mcastgrp = *mcastgrp,
954 	};
955 
956 	if (ipv6_addr_any(mcastgrp))
957 		return mr_mfc_find_any_parent(mrt, mifi);
958 	return mr_mfc_find_any(mrt, mifi, &arg);
959 }
960 
961 /* Look for a (S,G,iif) entry if parent != -1 */
962 static struct mfc6_cache *
963 ip6mr_cache_find_parent(struct mr_table *mrt,
964 			const struct in6_addr *origin,
965 			const struct in6_addr *mcastgrp,
966 			int parent)
967 {
968 	struct mfc6_cache_cmp_arg arg = {
969 		.mf6c_origin = *origin,
970 		.mf6c_mcastgrp = *mcastgrp,
971 	};
972 
973 	return mr_mfc_find_parent(mrt, &arg, parent);
974 }
975 
976 /* Allocate a multicast cache entry */
977 static struct mfc6_cache *ip6mr_cache_alloc(void)
978 {
979 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
980 	if (!c)
981 		return NULL;
982 	c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
983 	c->_c.mfc_un.res.minvif = MAXMIFS;
984 	c->_c.free = ip6mr_cache_free_rcu;
985 	refcount_set(&c->_c.mfc_un.res.refcount, 1);
986 	return c;
987 }
988 
989 static struct mfc6_cache *ip6mr_cache_alloc_unres(void)
990 {
991 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
992 	if (!c)
993 		return NULL;
994 	skb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
995 	c->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
996 	return c;
997 }
998 
999 /*
1000  *	A cache entry has gone into a resolved state from queued
1001  */
1002 
1003 static void ip6mr_cache_resolve(struct net *net, struct mr_table *mrt,
1004 				struct mfc6_cache *uc, struct mfc6_cache *c)
1005 {
1006 	struct sk_buff *skb;
1007 
1008 	/*
1009 	 *	Play the pending entries through our router
1010 	 */
1011 
1012 	while ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
1013 		if (ipv6_hdr(skb)->version == 0) {
1014 			struct nlmsghdr *nlh = skb_pull(skb,
1015 							sizeof(struct ipv6hdr));
1016 
1017 			if (mr_fill_mroute(mrt, skb, &c->_c,
1018 					   nlmsg_data(nlh)) > 0) {
1019 				nlh->nlmsg_len = skb_tail_pointer(skb) - (u8 *)nlh;
1020 			} else {
1021 				nlh->nlmsg_type = NLMSG_ERROR;
1022 				nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
1023 				skb_trim(skb, nlh->nlmsg_len);
1024 				((struct nlmsgerr *)nlmsg_data(nlh))->error = -EMSGSIZE;
1025 			}
1026 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
1027 		} else
1028 			ip6_mr_forward(net, mrt, skb->dev, skb, c);
1029 	}
1030 }
1031 
1032 /*
1033  *	Bounce a cache query up to pim6sd and netlink.
1034  *
1035  *	Called under mrt_lock.
1036  */
1037 
1038 static int ip6mr_cache_report(struct mr_table *mrt, struct sk_buff *pkt,
1039 			      mifi_t mifi, int assert)
1040 {
1041 	struct sock *mroute6_sk;
1042 	struct sk_buff *skb;
1043 	struct mrt6msg *msg;
1044 	int ret;
1045 
1046 #ifdef CONFIG_IPV6_PIMSM_V2
1047 	if (assert == MRT6MSG_WHOLEPKT)
1048 		skb = skb_realloc_headroom(pkt, -skb_network_offset(pkt)
1049 						+sizeof(*msg));
1050 	else
1051 #endif
1052 		skb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(*msg), GFP_ATOMIC);
1053 
1054 	if (!skb)
1055 		return -ENOBUFS;
1056 
1057 	/* I suppose that internal messages
1058 	 * do not require checksums */
1059 
1060 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1061 
1062 #ifdef CONFIG_IPV6_PIMSM_V2
1063 	if (assert == MRT6MSG_WHOLEPKT) {
1064 		/* Ugly, but we have no choice with this interface.
1065 		   Duplicate old header, fix length etc.
1066 		   And all this only to mangle msg->im6_msgtype and
1067 		   to set msg->im6_mbz to "mbz" :-)
1068 		 */
1069 		skb_push(skb, -skb_network_offset(pkt));
1070 
1071 		skb_push(skb, sizeof(*msg));
1072 		skb_reset_transport_header(skb);
1073 		msg = (struct mrt6msg *)skb_transport_header(skb);
1074 		msg->im6_mbz = 0;
1075 		msg->im6_msgtype = MRT6MSG_WHOLEPKT;
1076 		msg->im6_mif = mrt->mroute_reg_vif_num;
1077 		msg->im6_pad = 0;
1078 		msg->im6_src = ipv6_hdr(pkt)->saddr;
1079 		msg->im6_dst = ipv6_hdr(pkt)->daddr;
1080 
1081 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1082 	} else
1083 #endif
1084 	{
1085 	/*
1086 	 *	Copy the IP header
1087 	 */
1088 
1089 	skb_put(skb, sizeof(struct ipv6hdr));
1090 	skb_reset_network_header(skb);
1091 	skb_copy_to_linear_data(skb, ipv6_hdr(pkt), sizeof(struct ipv6hdr));
1092 
1093 	/*
1094 	 *	Add our header
1095 	 */
1096 	skb_put(skb, sizeof(*msg));
1097 	skb_reset_transport_header(skb);
1098 	msg = (struct mrt6msg *)skb_transport_header(skb);
1099 
1100 	msg->im6_mbz = 0;
1101 	msg->im6_msgtype = assert;
1102 	msg->im6_mif = mifi;
1103 	msg->im6_pad = 0;
1104 	msg->im6_src = ipv6_hdr(pkt)->saddr;
1105 	msg->im6_dst = ipv6_hdr(pkt)->daddr;
1106 
1107 	skb_dst_set(skb, dst_clone(skb_dst(pkt)));
1108 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1109 	}
1110 
1111 	rcu_read_lock();
1112 	mroute6_sk = rcu_dereference(mrt->mroute_sk);
1113 	if (!mroute6_sk) {
1114 		rcu_read_unlock();
1115 		kfree_skb(skb);
1116 		return -EINVAL;
1117 	}
1118 
1119 	mrt6msg_netlink_event(mrt, skb);
1120 
1121 	/* Deliver to user space multicast routing algorithms */
1122 	ret = sock_queue_rcv_skb(mroute6_sk, skb);
1123 	rcu_read_unlock();
1124 	if (ret < 0) {
1125 		net_warn_ratelimited("mroute6: pending queue full, dropping entries\n");
1126 		kfree_skb(skb);
1127 	}
1128 
1129 	return ret;
1130 }
1131 
1132 /* Queue a packet for resolution. It gets locked cache entry! */
1133 static int ip6mr_cache_unresolved(struct mr_table *mrt, mifi_t mifi,
1134 				  struct sk_buff *skb, struct net_device *dev)
1135 {
1136 	struct mfc6_cache *c;
1137 	bool found = false;
1138 	int err;
1139 
1140 	spin_lock_bh(&mfc_unres_lock);
1141 	list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
1142 		if (ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&
1143 		    ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr)) {
1144 			found = true;
1145 			break;
1146 		}
1147 	}
1148 
1149 	if (!found) {
1150 		/*
1151 		 *	Create a new entry if allowable
1152 		 */
1153 
1154 		c = ip6mr_cache_alloc_unres();
1155 		if (!c) {
1156 			spin_unlock_bh(&mfc_unres_lock);
1157 
1158 			kfree_skb(skb);
1159 			return -ENOBUFS;
1160 		}
1161 
1162 		/* Fill in the new cache entry */
1163 		c->_c.mfc_parent = -1;
1164 		c->mf6c_origin = ipv6_hdr(skb)->saddr;
1165 		c->mf6c_mcastgrp = ipv6_hdr(skb)->daddr;
1166 
1167 		/*
1168 		 *	Reflect first query at pim6sd
1169 		 */
1170 		err = ip6mr_cache_report(mrt, skb, mifi, MRT6MSG_NOCACHE);
1171 		if (err < 0) {
1172 			/* If the report failed throw the cache entry
1173 			   out - Brad Parker
1174 			 */
1175 			spin_unlock_bh(&mfc_unres_lock);
1176 
1177 			ip6mr_cache_free(c);
1178 			kfree_skb(skb);
1179 			return err;
1180 		}
1181 
1182 		atomic_inc(&mrt->cache_resolve_queue_len);
1183 		list_add(&c->_c.list, &mrt->mfc_unres_queue);
1184 		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1185 
1186 		ipmr_do_expire_process(mrt);
1187 	}
1188 
1189 	/* See if we can append the packet */
1190 	if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
1191 		kfree_skb(skb);
1192 		err = -ENOBUFS;
1193 	} else {
1194 		if (dev) {
1195 			skb->dev = dev;
1196 			skb->skb_iif = dev->ifindex;
1197 		}
1198 		skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
1199 		err = 0;
1200 	}
1201 
1202 	spin_unlock_bh(&mfc_unres_lock);
1203 	return err;
1204 }
1205 
1206 /*
1207  *	MFC6 cache manipulation by user space
1208  */
1209 
1210 static int ip6mr_mfc_delete(struct mr_table *mrt, struct mf6cctl *mfc,
1211 			    int parent)
1212 {
1213 	struct mfc6_cache *c;
1214 
1215 	/* The entries are added/deleted only under RTNL */
1216 	rcu_read_lock();
1217 	c = ip6mr_cache_find_parent(mrt, &mfc->mf6cc_origin.sin6_addr,
1218 				    &mfc->mf6cc_mcastgrp.sin6_addr, parent);
1219 	rcu_read_unlock();
1220 	if (!c)
1221 		return -ENOENT;
1222 	rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ip6mr_rht_params);
1223 	list_del_rcu(&c->_c.list);
1224 
1225 	call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
1226 				       FIB_EVENT_ENTRY_DEL, c, mrt->id);
1227 	mr6_netlink_event(mrt, c, RTM_DELROUTE);
1228 	mr_cache_put(&c->_c);
1229 	return 0;
1230 }
1231 
1232 static int ip6mr_device_event(struct notifier_block *this,
1233 			      unsigned long event, void *ptr)
1234 {
1235 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1236 	struct net *net = dev_net(dev);
1237 	struct mr_table *mrt;
1238 	struct vif_device *v;
1239 	int ct;
1240 
1241 	if (event != NETDEV_UNREGISTER)
1242 		return NOTIFY_DONE;
1243 
1244 	ip6mr_for_each_table(mrt, net) {
1245 		v = &mrt->vif_table[0];
1246 		for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1247 			if (v->dev == dev)
1248 				mif6_delete(mrt, ct, 1, NULL);
1249 		}
1250 	}
1251 
1252 	return NOTIFY_DONE;
1253 }
1254 
1255 static unsigned int ip6mr_seq_read(struct net *net)
1256 {
1257 	ASSERT_RTNL();
1258 
1259 	return net->ipv6.ipmr_seq + ip6mr_rules_seq_read(net);
1260 }
1261 
1262 static int ip6mr_dump(struct net *net, struct notifier_block *nb,
1263 		      struct netlink_ext_ack *extack)
1264 {
1265 	return mr_dump(net, nb, RTNL_FAMILY_IP6MR, ip6mr_rules_dump,
1266 		       ip6mr_mr_table_iter, &mrt_lock, extack);
1267 }
1268 
1269 static struct notifier_block ip6_mr_notifier = {
1270 	.notifier_call = ip6mr_device_event
1271 };
1272 
1273 static const struct fib_notifier_ops ip6mr_notifier_ops_template = {
1274 	.family		= RTNL_FAMILY_IP6MR,
1275 	.fib_seq_read	= ip6mr_seq_read,
1276 	.fib_dump	= ip6mr_dump,
1277 	.owner		= THIS_MODULE,
1278 };
1279 
1280 static int __net_init ip6mr_notifier_init(struct net *net)
1281 {
1282 	struct fib_notifier_ops *ops;
1283 
1284 	net->ipv6.ipmr_seq = 0;
1285 
1286 	ops = fib_notifier_ops_register(&ip6mr_notifier_ops_template, net);
1287 	if (IS_ERR(ops))
1288 		return PTR_ERR(ops);
1289 
1290 	net->ipv6.ip6mr_notifier_ops = ops;
1291 
1292 	return 0;
1293 }
1294 
1295 static void __net_exit ip6mr_notifier_exit(struct net *net)
1296 {
1297 	fib_notifier_ops_unregister(net->ipv6.ip6mr_notifier_ops);
1298 	net->ipv6.ip6mr_notifier_ops = NULL;
1299 }
1300 
1301 /* Setup for IP multicast routing */
1302 static int __net_init ip6mr_net_init(struct net *net)
1303 {
1304 	int err;
1305 
1306 	err = ip6mr_notifier_init(net);
1307 	if (err)
1308 		return err;
1309 
1310 	err = ip6mr_rules_init(net);
1311 	if (err < 0)
1312 		goto ip6mr_rules_fail;
1313 
1314 #ifdef CONFIG_PROC_FS
1315 	err = -ENOMEM;
1316 	if (!proc_create_net("ip6_mr_vif", 0, net->proc_net, &ip6mr_vif_seq_ops,
1317 			sizeof(struct mr_vif_iter)))
1318 		goto proc_vif_fail;
1319 	if (!proc_create_net("ip6_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
1320 			sizeof(struct mr_mfc_iter)))
1321 		goto proc_cache_fail;
1322 #endif
1323 
1324 	return 0;
1325 
1326 #ifdef CONFIG_PROC_FS
1327 proc_cache_fail:
1328 	remove_proc_entry("ip6_mr_vif", net->proc_net);
1329 proc_vif_fail:
1330 	ip6mr_rules_exit(net);
1331 #endif
1332 ip6mr_rules_fail:
1333 	ip6mr_notifier_exit(net);
1334 	return err;
1335 }
1336 
1337 static void __net_exit ip6mr_net_exit(struct net *net)
1338 {
1339 #ifdef CONFIG_PROC_FS
1340 	remove_proc_entry("ip6_mr_cache", net->proc_net);
1341 	remove_proc_entry("ip6_mr_vif", net->proc_net);
1342 #endif
1343 	ip6mr_rules_exit(net);
1344 	ip6mr_notifier_exit(net);
1345 }
1346 
1347 static struct pernet_operations ip6mr_net_ops = {
1348 	.init = ip6mr_net_init,
1349 	.exit = ip6mr_net_exit,
1350 };
1351 
1352 int __init ip6_mr_init(void)
1353 {
1354 	int err;
1355 
1356 	mrt_cachep = kmem_cache_create("ip6_mrt_cache",
1357 				       sizeof(struct mfc6_cache),
1358 				       0, SLAB_HWCACHE_ALIGN,
1359 				       NULL);
1360 	if (!mrt_cachep)
1361 		return -ENOMEM;
1362 
1363 	err = register_pernet_subsys(&ip6mr_net_ops);
1364 	if (err)
1365 		goto reg_pernet_fail;
1366 
1367 	err = register_netdevice_notifier(&ip6_mr_notifier);
1368 	if (err)
1369 		goto reg_notif_fail;
1370 #ifdef CONFIG_IPV6_PIMSM_V2
1371 	if (inet6_add_protocol(&pim6_protocol, IPPROTO_PIM) < 0) {
1372 		pr_err("%s: can't add PIM protocol\n", __func__);
1373 		err = -EAGAIN;
1374 		goto add_proto_fail;
1375 	}
1376 #endif
1377 	err = rtnl_register_module(THIS_MODULE, RTNL_FAMILY_IP6MR, RTM_GETROUTE,
1378 				   NULL, ip6mr_rtm_dumproute, 0);
1379 	if (err == 0)
1380 		return 0;
1381 
1382 #ifdef CONFIG_IPV6_PIMSM_V2
1383 	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
1384 add_proto_fail:
1385 	unregister_netdevice_notifier(&ip6_mr_notifier);
1386 #endif
1387 reg_notif_fail:
1388 	unregister_pernet_subsys(&ip6mr_net_ops);
1389 reg_pernet_fail:
1390 	kmem_cache_destroy(mrt_cachep);
1391 	return err;
1392 }
1393 
1394 void ip6_mr_cleanup(void)
1395 {
1396 	rtnl_unregister(RTNL_FAMILY_IP6MR, RTM_GETROUTE);
1397 #ifdef CONFIG_IPV6_PIMSM_V2
1398 	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
1399 #endif
1400 	unregister_netdevice_notifier(&ip6_mr_notifier);
1401 	unregister_pernet_subsys(&ip6mr_net_ops);
1402 	kmem_cache_destroy(mrt_cachep);
1403 }
1404 
1405 static int ip6mr_mfc_add(struct net *net, struct mr_table *mrt,
1406 			 struct mf6cctl *mfc, int mrtsock, int parent)
1407 {
1408 	unsigned char ttls[MAXMIFS];
1409 	struct mfc6_cache *uc, *c;
1410 	struct mr_mfc *_uc;
1411 	bool found;
1412 	int i, err;
1413 
1414 	if (mfc->mf6cc_parent >= MAXMIFS)
1415 		return -ENFILE;
1416 
1417 	memset(ttls, 255, MAXMIFS);
1418 	for (i = 0; i < MAXMIFS; i++) {
1419 		if (IF_ISSET(i, &mfc->mf6cc_ifset))
1420 			ttls[i] = 1;
1421 	}
1422 
1423 	/* The entries are added/deleted only under RTNL */
1424 	rcu_read_lock();
1425 	c = ip6mr_cache_find_parent(mrt, &mfc->mf6cc_origin.sin6_addr,
1426 				    &mfc->mf6cc_mcastgrp.sin6_addr, parent);
1427 	rcu_read_unlock();
1428 	if (c) {
1429 		write_lock_bh(&mrt_lock);
1430 		c->_c.mfc_parent = mfc->mf6cc_parent;
1431 		ip6mr_update_thresholds(mrt, &c->_c, ttls);
1432 		if (!mrtsock)
1433 			c->_c.mfc_flags |= MFC_STATIC;
1434 		write_unlock_bh(&mrt_lock);
1435 		call_ip6mr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE,
1436 					       c, mrt->id);
1437 		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1438 		return 0;
1439 	}
1440 
1441 	if (!ipv6_addr_any(&mfc->mf6cc_mcastgrp.sin6_addr) &&
1442 	    !ipv6_addr_is_multicast(&mfc->mf6cc_mcastgrp.sin6_addr))
1443 		return -EINVAL;
1444 
1445 	c = ip6mr_cache_alloc();
1446 	if (!c)
1447 		return -ENOMEM;
1448 
1449 	c->mf6c_origin = mfc->mf6cc_origin.sin6_addr;
1450 	c->mf6c_mcastgrp = mfc->mf6cc_mcastgrp.sin6_addr;
1451 	c->_c.mfc_parent = mfc->mf6cc_parent;
1452 	ip6mr_update_thresholds(mrt, &c->_c, ttls);
1453 	if (!mrtsock)
1454 		c->_c.mfc_flags |= MFC_STATIC;
1455 
1456 	err = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
1457 				  ip6mr_rht_params);
1458 	if (err) {
1459 		pr_err("ip6mr: rhtable insert error %d\n", err);
1460 		ip6mr_cache_free(c);
1461 		return err;
1462 	}
1463 	list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
1464 
1465 	/* Check to see if we resolved a queued list. If so we
1466 	 * need to send on the frames and tidy up.
1467 	 */
1468 	found = false;
1469 	spin_lock_bh(&mfc_unres_lock);
1470 	list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
1471 		uc = (struct mfc6_cache *)_uc;
1472 		if (ipv6_addr_equal(&uc->mf6c_origin, &c->mf6c_origin) &&
1473 		    ipv6_addr_equal(&uc->mf6c_mcastgrp, &c->mf6c_mcastgrp)) {
1474 			list_del(&_uc->list);
1475 			atomic_dec(&mrt->cache_resolve_queue_len);
1476 			found = true;
1477 			break;
1478 		}
1479 	}
1480 	if (list_empty(&mrt->mfc_unres_queue))
1481 		del_timer(&mrt->ipmr_expire_timer);
1482 	spin_unlock_bh(&mfc_unres_lock);
1483 
1484 	if (found) {
1485 		ip6mr_cache_resolve(net, mrt, uc, c);
1486 		ip6mr_cache_free(uc);
1487 	}
1488 	call_ip6mr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD,
1489 				       c, mrt->id);
1490 	mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1491 	return 0;
1492 }
1493 
1494 /*
1495  *	Close the multicast socket, and clear the vif tables etc
1496  */
1497 
1498 static void mroute_clean_tables(struct mr_table *mrt, int flags)
1499 {
1500 	struct mr_mfc *c, *tmp;
1501 	LIST_HEAD(list);
1502 	int i;
1503 
1504 	/* Shut down all active vif entries */
1505 	if (flags & (MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC)) {
1506 		for (i = 0; i < mrt->maxvif; i++) {
1507 			if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
1508 			     !(flags & MRT6_FLUSH_MIFS_STATIC)) ||
1509 			    (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT6_FLUSH_MIFS)))
1510 				continue;
1511 			mif6_delete(mrt, i, 0, &list);
1512 		}
1513 		unregister_netdevice_many(&list);
1514 	}
1515 
1516 	/* Wipe the cache */
1517 	if (flags & (MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC)) {
1518 		list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
1519 			if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT6_FLUSH_MFC_STATIC)) ||
1520 			    (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT6_FLUSH_MFC)))
1521 				continue;
1522 			rhltable_remove(&mrt->mfc_hash, &c->mnode, ip6mr_rht_params);
1523 			list_del_rcu(&c->list);
1524 			call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
1525 						       FIB_EVENT_ENTRY_DEL,
1526 						       (struct mfc6_cache *)c, mrt->id);
1527 			mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
1528 			mr_cache_put(c);
1529 		}
1530 	}
1531 
1532 	if (flags & MRT6_FLUSH_MFC) {
1533 		if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1534 			spin_lock_bh(&mfc_unres_lock);
1535 			list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
1536 				list_del(&c->list);
1537 				mr6_netlink_event(mrt, (struct mfc6_cache *)c,
1538 						  RTM_DELROUTE);
1539 				ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
1540 			}
1541 			spin_unlock_bh(&mfc_unres_lock);
1542 		}
1543 	}
1544 }
1545 
1546 static int ip6mr_sk_init(struct mr_table *mrt, struct sock *sk)
1547 {
1548 	int err = 0;
1549 	struct net *net = sock_net(sk);
1550 
1551 	rtnl_lock();
1552 	write_lock_bh(&mrt_lock);
1553 	if (rtnl_dereference(mrt->mroute_sk)) {
1554 		err = -EADDRINUSE;
1555 	} else {
1556 		rcu_assign_pointer(mrt->mroute_sk, sk);
1557 		sock_set_flag(sk, SOCK_RCU_FREE);
1558 		net->ipv6.devconf_all->mc_forwarding++;
1559 	}
1560 	write_unlock_bh(&mrt_lock);
1561 
1562 	if (!err)
1563 		inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
1564 					     NETCONFA_MC_FORWARDING,
1565 					     NETCONFA_IFINDEX_ALL,
1566 					     net->ipv6.devconf_all);
1567 	rtnl_unlock();
1568 
1569 	return err;
1570 }
1571 
1572 int ip6mr_sk_done(struct sock *sk)
1573 {
1574 	int err = -EACCES;
1575 	struct net *net = sock_net(sk);
1576 	struct mr_table *mrt;
1577 
1578 	if (sk->sk_type != SOCK_RAW ||
1579 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1580 		return err;
1581 
1582 	rtnl_lock();
1583 	ip6mr_for_each_table(mrt, net) {
1584 		if (sk == rtnl_dereference(mrt->mroute_sk)) {
1585 			write_lock_bh(&mrt_lock);
1586 			RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1587 			/* Note that mroute_sk had SOCK_RCU_FREE set,
1588 			 * so the RCU grace period before sk freeing
1589 			 * is guaranteed by sk_destruct()
1590 			 */
1591 			net->ipv6.devconf_all->mc_forwarding--;
1592 			write_unlock_bh(&mrt_lock);
1593 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
1594 						     NETCONFA_MC_FORWARDING,
1595 						     NETCONFA_IFINDEX_ALL,
1596 						     net->ipv6.devconf_all);
1597 
1598 			mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MFC);
1599 			err = 0;
1600 			break;
1601 		}
1602 	}
1603 	rtnl_unlock();
1604 
1605 	return err;
1606 }
1607 
1608 bool mroute6_is_socket(struct net *net, struct sk_buff *skb)
1609 {
1610 	struct mr_table *mrt;
1611 	struct flowi6 fl6 = {
1612 		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
1613 		.flowi6_oif	= skb->dev->ifindex,
1614 		.flowi6_mark	= skb->mark,
1615 	};
1616 
1617 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
1618 		return NULL;
1619 
1620 	return rcu_access_pointer(mrt->mroute_sk);
1621 }
1622 EXPORT_SYMBOL(mroute6_is_socket);
1623 
1624 /*
1625  *	Socket options and virtual interface manipulation. The whole
1626  *	virtual interface system is a complete heap, but unfortunately
1627  *	that's how BSD mrouted happens to think. Maybe one day with a proper
1628  *	MOSPF/PIM router set up we can clean this up.
1629  */
1630 
1631 int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsigned int optlen)
1632 {
1633 	int ret, parent = 0;
1634 	struct mif6ctl vif;
1635 	struct mf6cctl mfc;
1636 	mifi_t mifi;
1637 	struct net *net = sock_net(sk);
1638 	struct mr_table *mrt;
1639 
1640 	if (sk->sk_type != SOCK_RAW ||
1641 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1642 		return -EOPNOTSUPP;
1643 
1644 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1645 	if (!mrt)
1646 		return -ENOENT;
1647 
1648 	if (optname != MRT6_INIT) {
1649 		if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1650 		    !ns_capable(net->user_ns, CAP_NET_ADMIN))
1651 			return -EACCES;
1652 	}
1653 
1654 	switch (optname) {
1655 	case MRT6_INIT:
1656 		if (optlen < sizeof(int))
1657 			return -EINVAL;
1658 
1659 		return ip6mr_sk_init(mrt, sk);
1660 
1661 	case MRT6_DONE:
1662 		return ip6mr_sk_done(sk);
1663 
1664 	case MRT6_ADD_MIF:
1665 		if (optlen < sizeof(vif))
1666 			return -EINVAL;
1667 		if (copy_from_user(&vif, optval, sizeof(vif)))
1668 			return -EFAULT;
1669 		if (vif.mif6c_mifi >= MAXMIFS)
1670 			return -ENFILE;
1671 		rtnl_lock();
1672 		ret = mif6_add(net, mrt, &vif,
1673 			       sk == rtnl_dereference(mrt->mroute_sk));
1674 		rtnl_unlock();
1675 		return ret;
1676 
1677 	case MRT6_DEL_MIF:
1678 		if (optlen < sizeof(mifi_t))
1679 			return -EINVAL;
1680 		if (copy_from_user(&mifi, optval, sizeof(mifi_t)))
1681 			return -EFAULT;
1682 		rtnl_lock();
1683 		ret = mif6_delete(mrt, mifi, 0, NULL);
1684 		rtnl_unlock();
1685 		return ret;
1686 
1687 	/*
1688 	 *	Manipulate the forwarding caches. These live
1689 	 *	in a sort of kernel/user symbiosis.
1690 	 */
1691 	case MRT6_ADD_MFC:
1692 	case MRT6_DEL_MFC:
1693 		parent = -1;
1694 		fallthrough;
1695 	case MRT6_ADD_MFC_PROXY:
1696 	case MRT6_DEL_MFC_PROXY:
1697 		if (optlen < sizeof(mfc))
1698 			return -EINVAL;
1699 		if (copy_from_user(&mfc, optval, sizeof(mfc)))
1700 			return -EFAULT;
1701 		if (parent == 0)
1702 			parent = mfc.mf6cc_parent;
1703 		rtnl_lock();
1704 		if (optname == MRT6_DEL_MFC || optname == MRT6_DEL_MFC_PROXY)
1705 			ret = ip6mr_mfc_delete(mrt, &mfc, parent);
1706 		else
1707 			ret = ip6mr_mfc_add(net, mrt, &mfc,
1708 					    sk ==
1709 					    rtnl_dereference(mrt->mroute_sk),
1710 					    parent);
1711 		rtnl_unlock();
1712 		return ret;
1713 
1714 	case MRT6_FLUSH:
1715 	{
1716 		int flags;
1717 
1718 		if (optlen != sizeof(flags))
1719 			return -EINVAL;
1720 		if (get_user(flags, (int __user *)optval))
1721 			return -EFAULT;
1722 		rtnl_lock();
1723 		mroute_clean_tables(mrt, flags);
1724 		rtnl_unlock();
1725 		return 0;
1726 	}
1727 
1728 	/*
1729 	 *	Control PIM assert (to activate pim will activate assert)
1730 	 */
1731 	case MRT6_ASSERT:
1732 	{
1733 		int v;
1734 
1735 		if (optlen != sizeof(v))
1736 			return -EINVAL;
1737 		if (get_user(v, (int __user *)optval))
1738 			return -EFAULT;
1739 		mrt->mroute_do_assert = v;
1740 		return 0;
1741 	}
1742 
1743 #ifdef CONFIG_IPV6_PIMSM_V2
1744 	case MRT6_PIM:
1745 	{
1746 		int v;
1747 
1748 		if (optlen != sizeof(v))
1749 			return -EINVAL;
1750 		if (get_user(v, (int __user *)optval))
1751 			return -EFAULT;
1752 		v = !!v;
1753 		rtnl_lock();
1754 		ret = 0;
1755 		if (v != mrt->mroute_do_pim) {
1756 			mrt->mroute_do_pim = v;
1757 			mrt->mroute_do_assert = v;
1758 		}
1759 		rtnl_unlock();
1760 		return ret;
1761 	}
1762 
1763 #endif
1764 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
1765 	case MRT6_TABLE:
1766 	{
1767 		u32 v;
1768 
1769 		if (optlen != sizeof(u32))
1770 			return -EINVAL;
1771 		if (get_user(v, (u32 __user *)optval))
1772 			return -EFAULT;
1773 		/* "pim6reg%u" should not exceed 16 bytes (IFNAMSIZ) */
1774 		if (v != RT_TABLE_DEFAULT && v >= 100000000)
1775 			return -EINVAL;
1776 		if (sk == rcu_access_pointer(mrt->mroute_sk))
1777 			return -EBUSY;
1778 
1779 		rtnl_lock();
1780 		ret = 0;
1781 		mrt = ip6mr_new_table(net, v);
1782 		if (IS_ERR(mrt))
1783 			ret = PTR_ERR(mrt);
1784 		else
1785 			raw6_sk(sk)->ip6mr_table = v;
1786 		rtnl_unlock();
1787 		return ret;
1788 	}
1789 #endif
1790 	/*
1791 	 *	Spurious command, or MRT6_VERSION which you cannot
1792 	 *	set.
1793 	 */
1794 	default:
1795 		return -ENOPROTOOPT;
1796 	}
1797 }
1798 
1799 /*
1800  *	Getsock opt support for the multicast routing system.
1801  */
1802 
1803 int ip6_mroute_getsockopt(struct sock *sk, int optname, char __user *optval,
1804 			  int __user *optlen)
1805 {
1806 	int olr;
1807 	int val;
1808 	struct net *net = sock_net(sk);
1809 	struct mr_table *mrt;
1810 
1811 	if (sk->sk_type != SOCK_RAW ||
1812 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1813 		return -EOPNOTSUPP;
1814 
1815 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1816 	if (!mrt)
1817 		return -ENOENT;
1818 
1819 	switch (optname) {
1820 	case MRT6_VERSION:
1821 		val = 0x0305;
1822 		break;
1823 #ifdef CONFIG_IPV6_PIMSM_V2
1824 	case MRT6_PIM:
1825 		val = mrt->mroute_do_pim;
1826 		break;
1827 #endif
1828 	case MRT6_ASSERT:
1829 		val = mrt->mroute_do_assert;
1830 		break;
1831 	default:
1832 		return -ENOPROTOOPT;
1833 	}
1834 
1835 	if (get_user(olr, optlen))
1836 		return -EFAULT;
1837 
1838 	olr = min_t(int, olr, sizeof(int));
1839 	if (olr < 0)
1840 		return -EINVAL;
1841 
1842 	if (put_user(olr, optlen))
1843 		return -EFAULT;
1844 	if (copy_to_user(optval, &val, olr))
1845 		return -EFAULT;
1846 	return 0;
1847 }
1848 
1849 /*
1850  *	The IP multicast ioctl support routines.
1851  */
1852 
1853 int ip6mr_ioctl(struct sock *sk, int cmd, void __user *arg)
1854 {
1855 	struct sioc_sg_req6 sr;
1856 	struct sioc_mif_req6 vr;
1857 	struct vif_device *vif;
1858 	struct mfc6_cache *c;
1859 	struct net *net = sock_net(sk);
1860 	struct mr_table *mrt;
1861 
1862 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1863 	if (!mrt)
1864 		return -ENOENT;
1865 
1866 	switch (cmd) {
1867 	case SIOCGETMIFCNT_IN6:
1868 		if (copy_from_user(&vr, arg, sizeof(vr)))
1869 			return -EFAULT;
1870 		if (vr.mifi >= mrt->maxvif)
1871 			return -EINVAL;
1872 		vr.mifi = array_index_nospec(vr.mifi, mrt->maxvif);
1873 		read_lock(&mrt_lock);
1874 		vif = &mrt->vif_table[vr.mifi];
1875 		if (VIF_EXISTS(mrt, vr.mifi)) {
1876 			vr.icount = vif->pkt_in;
1877 			vr.ocount = vif->pkt_out;
1878 			vr.ibytes = vif->bytes_in;
1879 			vr.obytes = vif->bytes_out;
1880 			read_unlock(&mrt_lock);
1881 
1882 			if (copy_to_user(arg, &vr, sizeof(vr)))
1883 				return -EFAULT;
1884 			return 0;
1885 		}
1886 		read_unlock(&mrt_lock);
1887 		return -EADDRNOTAVAIL;
1888 	case SIOCGETSGCNT_IN6:
1889 		if (copy_from_user(&sr, arg, sizeof(sr)))
1890 			return -EFAULT;
1891 
1892 		rcu_read_lock();
1893 		c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
1894 		if (c) {
1895 			sr.pktcnt = c->_c.mfc_un.res.pkt;
1896 			sr.bytecnt = c->_c.mfc_un.res.bytes;
1897 			sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1898 			rcu_read_unlock();
1899 
1900 			if (copy_to_user(arg, &sr, sizeof(sr)))
1901 				return -EFAULT;
1902 			return 0;
1903 		}
1904 		rcu_read_unlock();
1905 		return -EADDRNOTAVAIL;
1906 	default:
1907 		return -ENOIOCTLCMD;
1908 	}
1909 }
1910 
1911 #ifdef CONFIG_COMPAT
1912 struct compat_sioc_sg_req6 {
1913 	struct sockaddr_in6 src;
1914 	struct sockaddr_in6 grp;
1915 	compat_ulong_t pktcnt;
1916 	compat_ulong_t bytecnt;
1917 	compat_ulong_t wrong_if;
1918 };
1919 
1920 struct compat_sioc_mif_req6 {
1921 	mifi_t	mifi;
1922 	compat_ulong_t icount;
1923 	compat_ulong_t ocount;
1924 	compat_ulong_t ibytes;
1925 	compat_ulong_t obytes;
1926 };
1927 
1928 int ip6mr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1929 {
1930 	struct compat_sioc_sg_req6 sr;
1931 	struct compat_sioc_mif_req6 vr;
1932 	struct vif_device *vif;
1933 	struct mfc6_cache *c;
1934 	struct net *net = sock_net(sk);
1935 	struct mr_table *mrt;
1936 
1937 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1938 	if (!mrt)
1939 		return -ENOENT;
1940 
1941 	switch (cmd) {
1942 	case SIOCGETMIFCNT_IN6:
1943 		if (copy_from_user(&vr, arg, sizeof(vr)))
1944 			return -EFAULT;
1945 		if (vr.mifi >= mrt->maxvif)
1946 			return -EINVAL;
1947 		vr.mifi = array_index_nospec(vr.mifi, mrt->maxvif);
1948 		read_lock(&mrt_lock);
1949 		vif = &mrt->vif_table[vr.mifi];
1950 		if (VIF_EXISTS(mrt, vr.mifi)) {
1951 			vr.icount = vif->pkt_in;
1952 			vr.ocount = vif->pkt_out;
1953 			vr.ibytes = vif->bytes_in;
1954 			vr.obytes = vif->bytes_out;
1955 			read_unlock(&mrt_lock);
1956 
1957 			if (copy_to_user(arg, &vr, sizeof(vr)))
1958 				return -EFAULT;
1959 			return 0;
1960 		}
1961 		read_unlock(&mrt_lock);
1962 		return -EADDRNOTAVAIL;
1963 	case SIOCGETSGCNT_IN6:
1964 		if (copy_from_user(&sr, arg, sizeof(sr)))
1965 			return -EFAULT;
1966 
1967 		rcu_read_lock();
1968 		c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
1969 		if (c) {
1970 			sr.pktcnt = c->_c.mfc_un.res.pkt;
1971 			sr.bytecnt = c->_c.mfc_un.res.bytes;
1972 			sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1973 			rcu_read_unlock();
1974 
1975 			if (copy_to_user(arg, &sr, sizeof(sr)))
1976 				return -EFAULT;
1977 			return 0;
1978 		}
1979 		rcu_read_unlock();
1980 		return -EADDRNOTAVAIL;
1981 	default:
1982 		return -ENOIOCTLCMD;
1983 	}
1984 }
1985 #endif
1986 
1987 static inline int ip6mr_forward2_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
1988 {
1989 	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
1990 		      IPSTATS_MIB_OUTFORWDATAGRAMS);
1991 	IP6_ADD_STATS(net, ip6_dst_idev(skb_dst(skb)),
1992 		      IPSTATS_MIB_OUTOCTETS, skb->len);
1993 	return dst_output(net, sk, skb);
1994 }
1995 
1996 /*
1997  *	Processing handlers for ip6mr_forward
1998  */
1999 
2000 static int ip6mr_forward2(struct net *net, struct mr_table *mrt,
2001 			  struct sk_buff *skb, int vifi)
2002 {
2003 	struct ipv6hdr *ipv6h;
2004 	struct vif_device *vif = &mrt->vif_table[vifi];
2005 	struct net_device *dev;
2006 	struct dst_entry *dst;
2007 	struct flowi6 fl6;
2008 
2009 	if (!vif->dev)
2010 		goto out_free;
2011 
2012 #ifdef CONFIG_IPV6_PIMSM_V2
2013 	if (vif->flags & MIFF_REGISTER) {
2014 		vif->pkt_out++;
2015 		vif->bytes_out += skb->len;
2016 		vif->dev->stats.tx_bytes += skb->len;
2017 		vif->dev->stats.tx_packets++;
2018 		ip6mr_cache_report(mrt, skb, vifi, MRT6MSG_WHOLEPKT);
2019 		goto out_free;
2020 	}
2021 #endif
2022 
2023 	ipv6h = ipv6_hdr(skb);
2024 
2025 	fl6 = (struct flowi6) {
2026 		.flowi6_oif = vif->link,
2027 		.daddr = ipv6h->daddr,
2028 	};
2029 
2030 	dst = ip6_route_output(net, NULL, &fl6);
2031 	if (dst->error) {
2032 		dst_release(dst);
2033 		goto out_free;
2034 	}
2035 
2036 	skb_dst_drop(skb);
2037 	skb_dst_set(skb, dst);
2038 
2039 	/*
2040 	 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
2041 	 * not only before forwarding, but after forwarding on all output
2042 	 * interfaces. It is clear, if mrouter runs a multicasting
2043 	 * program, it should receive packets not depending to what interface
2044 	 * program is joined.
2045 	 * If we will not make it, the program will have to join on all
2046 	 * interfaces. On the other hand, multihoming host (or router, but
2047 	 * not mrouter) cannot join to more than one interface - it will
2048 	 * result in receiving multiple packets.
2049 	 */
2050 	dev = vif->dev;
2051 	skb->dev = dev;
2052 	vif->pkt_out++;
2053 	vif->bytes_out += skb->len;
2054 
2055 	/* We are about to write */
2056 	/* XXX: extension headers? */
2057 	if (skb_cow(skb, sizeof(*ipv6h) + LL_RESERVED_SPACE(dev)))
2058 		goto out_free;
2059 
2060 	ipv6h = ipv6_hdr(skb);
2061 	ipv6h->hop_limit--;
2062 
2063 	IP6CB(skb)->flags |= IP6SKB_FORWARDED;
2064 
2065 	return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
2066 		       net, NULL, skb, skb->dev, dev,
2067 		       ip6mr_forward2_finish);
2068 
2069 out_free:
2070 	kfree_skb(skb);
2071 	return 0;
2072 }
2073 
2074 static int ip6mr_find_vif(struct mr_table *mrt, struct net_device *dev)
2075 {
2076 	int ct;
2077 
2078 	for (ct = mrt->maxvif - 1; ct >= 0; ct--) {
2079 		if (mrt->vif_table[ct].dev == dev)
2080 			break;
2081 	}
2082 	return ct;
2083 }
2084 
2085 static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
2086 			   struct net_device *dev, struct sk_buff *skb,
2087 			   struct mfc6_cache *c)
2088 {
2089 	int psend = -1;
2090 	int vif, ct;
2091 	int true_vifi = ip6mr_find_vif(mrt, dev);
2092 
2093 	vif = c->_c.mfc_parent;
2094 	c->_c.mfc_un.res.pkt++;
2095 	c->_c.mfc_un.res.bytes += skb->len;
2096 	c->_c.mfc_un.res.lastuse = jiffies;
2097 
2098 	if (ipv6_addr_any(&c->mf6c_origin) && true_vifi >= 0) {
2099 		struct mfc6_cache *cache_proxy;
2100 
2101 		/* For an (*,G) entry, we only check that the incoming
2102 		 * interface is part of the static tree.
2103 		 */
2104 		rcu_read_lock();
2105 		cache_proxy = mr_mfc_find_any_parent(mrt, vif);
2106 		if (cache_proxy &&
2107 		    cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255) {
2108 			rcu_read_unlock();
2109 			goto forward;
2110 		}
2111 		rcu_read_unlock();
2112 	}
2113 
2114 	/*
2115 	 * Wrong interface: drop packet and (maybe) send PIM assert.
2116 	 */
2117 	if (mrt->vif_table[vif].dev != dev) {
2118 		c->_c.mfc_un.res.wrong_if++;
2119 
2120 		if (true_vifi >= 0 && mrt->mroute_do_assert &&
2121 		    /* pimsm uses asserts, when switching from RPT to SPT,
2122 		       so that we cannot check that packet arrived on an oif.
2123 		       It is bad, but otherwise we would need to move pretty
2124 		       large chunk of pimd to kernel. Ough... --ANK
2125 		     */
2126 		    (mrt->mroute_do_pim ||
2127 		     c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
2128 		    time_after(jiffies,
2129 			       c->_c.mfc_un.res.last_assert +
2130 			       MFC_ASSERT_THRESH)) {
2131 			c->_c.mfc_un.res.last_assert = jiffies;
2132 			ip6mr_cache_report(mrt, skb, true_vifi, MRT6MSG_WRONGMIF);
2133 		}
2134 		goto dont_forward;
2135 	}
2136 
2137 forward:
2138 	mrt->vif_table[vif].pkt_in++;
2139 	mrt->vif_table[vif].bytes_in += skb->len;
2140 
2141 	/*
2142 	 *	Forward the frame
2143 	 */
2144 	if (ipv6_addr_any(&c->mf6c_origin) &&
2145 	    ipv6_addr_any(&c->mf6c_mcastgrp)) {
2146 		if (true_vifi >= 0 &&
2147 		    true_vifi != c->_c.mfc_parent &&
2148 		    ipv6_hdr(skb)->hop_limit >
2149 				c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
2150 			/* It's an (*,*) entry and the packet is not coming from
2151 			 * the upstream: forward the packet to the upstream
2152 			 * only.
2153 			 */
2154 			psend = c->_c.mfc_parent;
2155 			goto last_forward;
2156 		}
2157 		goto dont_forward;
2158 	}
2159 	for (ct = c->_c.mfc_un.res.maxvif - 1;
2160 	     ct >= c->_c.mfc_un.res.minvif; ct--) {
2161 		/* For (*,G) entry, don't forward to the incoming interface */
2162 		if ((!ipv6_addr_any(&c->mf6c_origin) || ct != true_vifi) &&
2163 		    ipv6_hdr(skb)->hop_limit > c->_c.mfc_un.res.ttls[ct]) {
2164 			if (psend != -1) {
2165 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2166 				if (skb2)
2167 					ip6mr_forward2(net, mrt, skb2, psend);
2168 			}
2169 			psend = ct;
2170 		}
2171 	}
2172 last_forward:
2173 	if (psend != -1) {
2174 		ip6mr_forward2(net, mrt, skb, psend);
2175 		return;
2176 	}
2177 
2178 dont_forward:
2179 	kfree_skb(skb);
2180 }
2181 
2182 
2183 /*
2184  *	Multicast packets for forwarding arrive here
2185  */
2186 
2187 int ip6_mr_input(struct sk_buff *skb)
2188 {
2189 	struct mfc6_cache *cache;
2190 	struct net *net = dev_net(skb->dev);
2191 	struct mr_table *mrt;
2192 	struct flowi6 fl6 = {
2193 		.flowi6_iif	= skb->dev->ifindex,
2194 		.flowi6_mark	= skb->mark,
2195 	};
2196 	int err;
2197 	struct net_device *dev;
2198 
2199 	/* skb->dev passed in is the master dev for vrfs.
2200 	 * Get the proper interface that does have a vif associated with it.
2201 	 */
2202 	dev = skb->dev;
2203 	if (netif_is_l3_master(skb->dev)) {
2204 		dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
2205 		if (!dev) {
2206 			kfree_skb(skb);
2207 			return -ENODEV;
2208 		}
2209 	}
2210 
2211 	err = ip6mr_fib_lookup(net, &fl6, &mrt);
2212 	if (err < 0) {
2213 		kfree_skb(skb);
2214 		return err;
2215 	}
2216 
2217 	read_lock(&mrt_lock);
2218 	cache = ip6mr_cache_find(mrt,
2219 				 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr);
2220 	if (!cache) {
2221 		int vif = ip6mr_find_vif(mrt, dev);
2222 
2223 		if (vif >= 0)
2224 			cache = ip6mr_cache_find_any(mrt,
2225 						     &ipv6_hdr(skb)->daddr,
2226 						     vif);
2227 	}
2228 
2229 	/*
2230 	 *	No usable cache entry
2231 	 */
2232 	if (!cache) {
2233 		int vif;
2234 
2235 		vif = ip6mr_find_vif(mrt, dev);
2236 		if (vif >= 0) {
2237 			int err = ip6mr_cache_unresolved(mrt, vif, skb, dev);
2238 			read_unlock(&mrt_lock);
2239 
2240 			return err;
2241 		}
2242 		read_unlock(&mrt_lock);
2243 		kfree_skb(skb);
2244 		return -ENODEV;
2245 	}
2246 
2247 	ip6_mr_forward(net, mrt, dev, skb, cache);
2248 
2249 	read_unlock(&mrt_lock);
2250 
2251 	return 0;
2252 }
2253 
2254 int ip6mr_get_route(struct net *net, struct sk_buff *skb, struct rtmsg *rtm,
2255 		    u32 portid)
2256 {
2257 	int err;
2258 	struct mr_table *mrt;
2259 	struct mfc6_cache *cache;
2260 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
2261 
2262 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
2263 	if (!mrt)
2264 		return -ENOENT;
2265 
2266 	read_lock(&mrt_lock);
2267 	cache = ip6mr_cache_find(mrt, &rt->rt6i_src.addr, &rt->rt6i_dst.addr);
2268 	if (!cache && skb->dev) {
2269 		int vif = ip6mr_find_vif(mrt, skb->dev);
2270 
2271 		if (vif >= 0)
2272 			cache = ip6mr_cache_find_any(mrt, &rt->rt6i_dst.addr,
2273 						     vif);
2274 	}
2275 
2276 	if (!cache) {
2277 		struct sk_buff *skb2;
2278 		struct ipv6hdr *iph;
2279 		struct net_device *dev;
2280 		int vif;
2281 
2282 		dev = skb->dev;
2283 		if (!dev || (vif = ip6mr_find_vif(mrt, dev)) < 0) {
2284 			read_unlock(&mrt_lock);
2285 			return -ENODEV;
2286 		}
2287 
2288 		/* really correct? */
2289 		skb2 = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
2290 		if (!skb2) {
2291 			read_unlock(&mrt_lock);
2292 			return -ENOMEM;
2293 		}
2294 
2295 		NETLINK_CB(skb2).portid = portid;
2296 		skb_reset_transport_header(skb2);
2297 
2298 		skb_put(skb2, sizeof(struct ipv6hdr));
2299 		skb_reset_network_header(skb2);
2300 
2301 		iph = ipv6_hdr(skb2);
2302 		iph->version = 0;
2303 		iph->priority = 0;
2304 		iph->flow_lbl[0] = 0;
2305 		iph->flow_lbl[1] = 0;
2306 		iph->flow_lbl[2] = 0;
2307 		iph->payload_len = 0;
2308 		iph->nexthdr = IPPROTO_NONE;
2309 		iph->hop_limit = 0;
2310 		iph->saddr = rt->rt6i_src.addr;
2311 		iph->daddr = rt->rt6i_dst.addr;
2312 
2313 		err = ip6mr_cache_unresolved(mrt, vif, skb2, dev);
2314 		read_unlock(&mrt_lock);
2315 
2316 		return err;
2317 	}
2318 
2319 	err = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
2320 	read_unlock(&mrt_lock);
2321 	return err;
2322 }
2323 
2324 static int ip6mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2325 			     u32 portid, u32 seq, struct mfc6_cache *c, int cmd,
2326 			     int flags)
2327 {
2328 	struct nlmsghdr *nlh;
2329 	struct rtmsg *rtm;
2330 	int err;
2331 
2332 	nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2333 	if (!nlh)
2334 		return -EMSGSIZE;
2335 
2336 	rtm = nlmsg_data(nlh);
2337 	rtm->rtm_family   = RTNL_FAMILY_IP6MR;
2338 	rtm->rtm_dst_len  = 128;
2339 	rtm->rtm_src_len  = 128;
2340 	rtm->rtm_tos      = 0;
2341 	rtm->rtm_table    = mrt->id;
2342 	if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2343 		goto nla_put_failure;
2344 	rtm->rtm_type = RTN_MULTICAST;
2345 	rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2346 	if (c->_c.mfc_flags & MFC_STATIC)
2347 		rtm->rtm_protocol = RTPROT_STATIC;
2348 	else
2349 		rtm->rtm_protocol = RTPROT_MROUTED;
2350 	rtm->rtm_flags    = 0;
2351 
2352 	if (nla_put_in6_addr(skb, RTA_SRC, &c->mf6c_origin) ||
2353 	    nla_put_in6_addr(skb, RTA_DST, &c->mf6c_mcastgrp))
2354 		goto nla_put_failure;
2355 	err = mr_fill_mroute(mrt, skb, &c->_c, rtm);
2356 	/* do not break the dump if cache is unresolved */
2357 	if (err < 0 && err != -ENOENT)
2358 		goto nla_put_failure;
2359 
2360 	nlmsg_end(skb, nlh);
2361 	return 0;
2362 
2363 nla_put_failure:
2364 	nlmsg_cancel(skb, nlh);
2365 	return -EMSGSIZE;
2366 }
2367 
2368 static int _ip6mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2369 			      u32 portid, u32 seq, struct mr_mfc *c,
2370 			      int cmd, int flags)
2371 {
2372 	return ip6mr_fill_mroute(mrt, skb, portid, seq, (struct mfc6_cache *)c,
2373 				 cmd, flags);
2374 }
2375 
2376 static int mr6_msgsize(bool unresolved, int maxvif)
2377 {
2378 	size_t len =
2379 		NLMSG_ALIGN(sizeof(struct rtmsg))
2380 		+ nla_total_size(4)	/* RTA_TABLE */
2381 		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_SRC */
2382 		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_DST */
2383 		;
2384 
2385 	if (!unresolved)
2386 		len = len
2387 		      + nla_total_size(4)	/* RTA_IIF */
2388 		      + nla_total_size(0)	/* RTA_MULTIPATH */
2389 		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2390 						/* RTA_MFC_STATS */
2391 		      + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
2392 		;
2393 
2394 	return len;
2395 }
2396 
2397 static void mr6_netlink_event(struct mr_table *mrt, struct mfc6_cache *mfc,
2398 			      int cmd)
2399 {
2400 	struct net *net = read_pnet(&mrt->net);
2401 	struct sk_buff *skb;
2402 	int err = -ENOBUFS;
2403 
2404 	skb = nlmsg_new(mr6_msgsize(mfc->_c.mfc_parent >= MAXMIFS, mrt->maxvif),
2405 			GFP_ATOMIC);
2406 	if (!skb)
2407 		goto errout;
2408 
2409 	err = ip6mr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2410 	if (err < 0)
2411 		goto errout;
2412 
2413 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE, NULL, GFP_ATOMIC);
2414 	return;
2415 
2416 errout:
2417 	kfree_skb(skb);
2418 	if (err < 0)
2419 		rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE, err);
2420 }
2421 
2422 static size_t mrt6msg_netlink_msgsize(size_t payloadlen)
2423 {
2424 	size_t len =
2425 		NLMSG_ALIGN(sizeof(struct rtgenmsg))
2426 		+ nla_total_size(1)	/* IP6MRA_CREPORT_MSGTYPE */
2427 		+ nla_total_size(4)	/* IP6MRA_CREPORT_MIF_ID */
2428 					/* IP6MRA_CREPORT_SRC_ADDR */
2429 		+ nla_total_size(sizeof(struct in6_addr))
2430 					/* IP6MRA_CREPORT_DST_ADDR */
2431 		+ nla_total_size(sizeof(struct in6_addr))
2432 					/* IP6MRA_CREPORT_PKT */
2433 		+ nla_total_size(payloadlen)
2434 		;
2435 
2436 	return len;
2437 }
2438 
2439 static void mrt6msg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
2440 {
2441 	struct net *net = read_pnet(&mrt->net);
2442 	struct nlmsghdr *nlh;
2443 	struct rtgenmsg *rtgenm;
2444 	struct mrt6msg *msg;
2445 	struct sk_buff *skb;
2446 	struct nlattr *nla;
2447 	int payloadlen;
2448 
2449 	payloadlen = pkt->len - sizeof(struct mrt6msg);
2450 	msg = (struct mrt6msg *)skb_transport_header(pkt);
2451 
2452 	skb = nlmsg_new(mrt6msg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2453 	if (!skb)
2454 		goto errout;
2455 
2456 	nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
2457 			sizeof(struct rtgenmsg), 0);
2458 	if (!nlh)
2459 		goto errout;
2460 	rtgenm = nlmsg_data(nlh);
2461 	rtgenm->rtgen_family = RTNL_FAMILY_IP6MR;
2462 	if (nla_put_u8(skb, IP6MRA_CREPORT_MSGTYPE, msg->im6_msgtype) ||
2463 	    nla_put_u32(skb, IP6MRA_CREPORT_MIF_ID, msg->im6_mif) ||
2464 	    nla_put_in6_addr(skb, IP6MRA_CREPORT_SRC_ADDR,
2465 			     &msg->im6_src) ||
2466 	    nla_put_in6_addr(skb, IP6MRA_CREPORT_DST_ADDR,
2467 			     &msg->im6_dst))
2468 		goto nla_put_failure;
2469 
2470 	nla = nla_reserve(skb, IP6MRA_CREPORT_PKT, payloadlen);
2471 	if (!nla || skb_copy_bits(pkt, sizeof(struct mrt6msg),
2472 				  nla_data(nla), payloadlen))
2473 		goto nla_put_failure;
2474 
2475 	nlmsg_end(skb, nlh);
2476 
2477 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE_R, NULL, GFP_ATOMIC);
2478 	return;
2479 
2480 nla_put_failure:
2481 	nlmsg_cancel(skb, nlh);
2482 errout:
2483 	kfree_skb(skb);
2484 	rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE_R, -ENOBUFS);
2485 }
2486 
2487 static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2488 {
2489 	const struct nlmsghdr *nlh = cb->nlh;
2490 	struct fib_dump_filter filter = {};
2491 	int err;
2492 
2493 	if (cb->strict_check) {
2494 		err = ip_valid_fib_dump_req(sock_net(skb->sk), nlh,
2495 					    &filter, cb);
2496 		if (err < 0)
2497 			return err;
2498 	}
2499 
2500 	if (filter.table_id) {
2501 		struct mr_table *mrt;
2502 
2503 		mrt = ip6mr_get_table(sock_net(skb->sk), filter.table_id);
2504 		if (!mrt) {
2505 			if (filter.dump_all_families)
2506 				return skb->len;
2507 
2508 			NL_SET_ERR_MSG_MOD(cb->extack, "MR table does not exist");
2509 			return -ENOENT;
2510 		}
2511 		err = mr_table_dump(mrt, skb, cb, _ip6mr_fill_mroute,
2512 				    &mfc_unres_lock, &filter);
2513 		return skb->len ? : err;
2514 	}
2515 
2516 	return mr_rtm_dumproute(skb, cb, ip6mr_mr_table_iter,
2517 				_ip6mr_fill_mroute, &mfc_unres_lock, &filter);
2518 }
2519