xref: /linux/net/ipv6/ip6mr.c (revision a1c3be890440a1769ed6f822376a3e3ab0d42994)
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 				list_empty(&net->ipv6.mr6_tables))
103 
104 static struct mr_table *ip6mr_mr_table_iter(struct net *net,
105 					    struct mr_table *mrt)
106 {
107 	struct mr_table *ret;
108 
109 	if (!mrt)
110 		ret = list_entry_rcu(net->ipv6.mr6_tables.next,
111 				     struct mr_table, list);
112 	else
113 		ret = list_entry_rcu(mrt->list.next,
114 				     struct mr_table, list);
115 
116 	if (&ret->list == &net->ipv6.mr6_tables)
117 		return NULL;
118 	return ret;
119 }
120 
121 static struct mr_table *ip6mr_get_table(struct net *net, u32 id)
122 {
123 	struct mr_table *mrt;
124 
125 	ip6mr_for_each_table(mrt, net) {
126 		if (mrt->id == id)
127 			return mrt;
128 	}
129 	return NULL;
130 }
131 
132 static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
133 			    struct mr_table **mrt)
134 {
135 	int err;
136 	struct ip6mr_result res;
137 	struct fib_lookup_arg arg = {
138 		.result = &res,
139 		.flags = FIB_LOOKUP_NOREF,
140 	};
141 
142 	/* update flow if oif or iif point to device enslaved to l3mdev */
143 	l3mdev_update_flow(net, flowi6_to_flowi(flp6));
144 
145 	err = fib_rules_lookup(net->ipv6.mr6_rules_ops,
146 			       flowi6_to_flowi(flp6), 0, &arg);
147 	if (err < 0)
148 		return err;
149 	*mrt = res.mrt;
150 	return 0;
151 }
152 
153 static int ip6mr_rule_action(struct fib_rule *rule, struct flowi *flp,
154 			     int flags, struct fib_lookup_arg *arg)
155 {
156 	struct ip6mr_result *res = arg->result;
157 	struct mr_table *mrt;
158 
159 	switch (rule->action) {
160 	case FR_ACT_TO_TBL:
161 		break;
162 	case FR_ACT_UNREACHABLE:
163 		return -ENETUNREACH;
164 	case FR_ACT_PROHIBIT:
165 		return -EACCES;
166 	case FR_ACT_BLACKHOLE:
167 	default:
168 		return -EINVAL;
169 	}
170 
171 	arg->table = fib_rule_get_table(rule, arg);
172 
173 	mrt = ip6mr_get_table(rule->fr_net, arg->table);
174 	if (!mrt)
175 		return -EAGAIN;
176 	res->mrt = mrt;
177 	return 0;
178 }
179 
180 static int ip6mr_rule_match(struct fib_rule *rule, struct flowi *flp, int flags)
181 {
182 	return 1;
183 }
184 
185 static const struct nla_policy ip6mr_rule_policy[FRA_MAX + 1] = {
186 	FRA_GENERIC_POLICY,
187 };
188 
189 static int ip6mr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
190 				struct fib_rule_hdr *frh, struct nlattr **tb,
191 				struct netlink_ext_ack *extack)
192 {
193 	return 0;
194 }
195 
196 static int ip6mr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
197 			      struct nlattr **tb)
198 {
199 	return 1;
200 }
201 
202 static int ip6mr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
203 			   struct fib_rule_hdr *frh)
204 {
205 	frh->dst_len = 0;
206 	frh->src_len = 0;
207 	frh->tos     = 0;
208 	return 0;
209 }
210 
211 static const struct fib_rules_ops __net_initconst ip6mr_rules_ops_template = {
212 	.family		= RTNL_FAMILY_IP6MR,
213 	.rule_size	= sizeof(struct ip6mr_rule),
214 	.addr_size	= sizeof(struct in6_addr),
215 	.action		= ip6mr_rule_action,
216 	.match		= ip6mr_rule_match,
217 	.configure	= ip6mr_rule_configure,
218 	.compare	= ip6mr_rule_compare,
219 	.fill		= ip6mr_rule_fill,
220 	.nlgroup	= RTNLGRP_IPV6_RULE,
221 	.policy		= ip6mr_rule_policy,
222 	.owner		= THIS_MODULE,
223 };
224 
225 static int __net_init ip6mr_rules_init(struct net *net)
226 {
227 	struct fib_rules_ops *ops;
228 	struct mr_table *mrt;
229 	int err;
230 
231 	ops = fib_rules_register(&ip6mr_rules_ops_template, net);
232 	if (IS_ERR(ops))
233 		return PTR_ERR(ops);
234 
235 	INIT_LIST_HEAD(&net->ipv6.mr6_tables);
236 
237 	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
238 	if (IS_ERR(mrt)) {
239 		err = PTR_ERR(mrt);
240 		goto err1;
241 	}
242 
243 	err = fib_default_rule_add(ops, 0x7fff, RT6_TABLE_DFLT, 0);
244 	if (err < 0)
245 		goto err2;
246 
247 	net->ipv6.mr6_rules_ops = ops;
248 	return 0;
249 
250 err2:
251 	ip6mr_free_table(mrt);
252 err1:
253 	fib_rules_unregister(ops);
254 	return err;
255 }
256 
257 static void __net_exit ip6mr_rules_exit(struct net *net)
258 {
259 	struct mr_table *mrt, *next;
260 
261 	rtnl_lock();
262 	list_for_each_entry_safe(mrt, next, &net->ipv6.mr6_tables, list) {
263 		list_del(&mrt->list);
264 		ip6mr_free_table(mrt);
265 	}
266 	fib_rules_unregister(net->ipv6.mr6_rules_ops);
267 	rtnl_unlock();
268 }
269 
270 static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
271 			    struct netlink_ext_ack *extack)
272 {
273 	return fib_rules_dump(net, nb, RTNL_FAMILY_IP6MR, extack);
274 }
275 
276 static unsigned int ip6mr_rules_seq_read(struct net *net)
277 {
278 	return fib_rules_seq_read(net, RTNL_FAMILY_IP6MR);
279 }
280 
281 bool ip6mr_rule_default(const struct fib_rule *rule)
282 {
283 	return fib_rule_matchall(rule) && rule->action == FR_ACT_TO_TBL &&
284 	       rule->table == RT6_TABLE_DFLT && !rule->l3mdev;
285 }
286 EXPORT_SYMBOL(ip6mr_rule_default);
287 #else
288 #define ip6mr_for_each_table(mrt, net) \
289 	for (mrt = net->ipv6.mrt6; mrt; mrt = NULL)
290 
291 static struct mr_table *ip6mr_mr_table_iter(struct net *net,
292 					    struct mr_table *mrt)
293 {
294 	if (!mrt)
295 		return net->ipv6.mrt6;
296 	return NULL;
297 }
298 
299 static struct mr_table *ip6mr_get_table(struct net *net, u32 id)
300 {
301 	return net->ipv6.mrt6;
302 }
303 
304 static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
305 			    struct mr_table **mrt)
306 {
307 	*mrt = net->ipv6.mrt6;
308 	return 0;
309 }
310 
311 static int __net_init ip6mr_rules_init(struct net *net)
312 {
313 	struct mr_table *mrt;
314 
315 	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
316 	if (IS_ERR(mrt))
317 		return PTR_ERR(mrt);
318 	net->ipv6.mrt6 = mrt;
319 	return 0;
320 }
321 
322 static void __net_exit ip6mr_rules_exit(struct net *net)
323 {
324 	rtnl_lock();
325 	ip6mr_free_table(net->ipv6.mrt6);
326 	net->ipv6.mrt6 = NULL;
327 	rtnl_unlock();
328 }
329 
330 static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
331 			    struct netlink_ext_ack *extack)
332 {
333 	return 0;
334 }
335 
336 static unsigned int ip6mr_rules_seq_read(struct net *net)
337 {
338 	return 0;
339 }
340 #endif
341 
342 static int ip6mr_hash_cmp(struct rhashtable_compare_arg *arg,
343 			  const void *ptr)
344 {
345 	const struct mfc6_cache_cmp_arg *cmparg = arg->key;
346 	struct mfc6_cache *c = (struct mfc6_cache *)ptr;
347 
348 	return !ipv6_addr_equal(&c->mf6c_mcastgrp, &cmparg->mf6c_mcastgrp) ||
349 	       !ipv6_addr_equal(&c->mf6c_origin, &cmparg->mf6c_origin);
350 }
351 
352 static const struct rhashtable_params ip6mr_rht_params = {
353 	.head_offset = offsetof(struct mr_mfc, mnode),
354 	.key_offset = offsetof(struct mfc6_cache, cmparg),
355 	.key_len = sizeof(struct mfc6_cache_cmp_arg),
356 	.nelem_hint = 3,
357 	.obj_cmpfn = ip6mr_hash_cmp,
358 	.automatic_shrinking = true,
359 };
360 
361 static void ip6mr_new_table_set(struct mr_table *mrt,
362 				struct net *net)
363 {
364 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
365 	list_add_tail_rcu(&mrt->list, &net->ipv6.mr6_tables);
366 #endif
367 }
368 
369 static struct mfc6_cache_cmp_arg ip6mr_mr_table_ops_cmparg_any = {
370 	.mf6c_origin = IN6ADDR_ANY_INIT,
371 	.mf6c_mcastgrp = IN6ADDR_ANY_INIT,
372 };
373 
374 static struct mr_table_ops ip6mr_mr_table_ops = {
375 	.rht_params = &ip6mr_rht_params,
376 	.cmparg_any = &ip6mr_mr_table_ops_cmparg_any,
377 };
378 
379 static struct mr_table *ip6mr_new_table(struct net *net, u32 id)
380 {
381 	struct mr_table *mrt;
382 
383 	mrt = ip6mr_get_table(net, id);
384 	if (mrt)
385 		return mrt;
386 
387 	return mr_table_alloc(net, id, &ip6mr_mr_table_ops,
388 			      ipmr_expire_process, ip6mr_new_table_set);
389 }
390 
391 static void ip6mr_free_table(struct mr_table *mrt)
392 {
393 	del_timer_sync(&mrt->ipmr_expire_timer);
394 	mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC |
395 				 MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC);
396 	rhltable_destroy(&mrt->mfc_hash);
397 	kfree(mrt);
398 }
399 
400 #ifdef CONFIG_PROC_FS
401 /* The /proc interfaces to multicast routing
402  * /proc/ip6_mr_cache /proc/ip6_mr_vif
403  */
404 
405 static void *ip6mr_vif_seq_start(struct seq_file *seq, loff_t *pos)
406 	__acquires(mrt_lock)
407 {
408 	struct mr_vif_iter *iter = seq->private;
409 	struct net *net = seq_file_net(seq);
410 	struct mr_table *mrt;
411 
412 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
413 	if (!mrt)
414 		return ERR_PTR(-ENOENT);
415 
416 	iter->mrt = mrt;
417 
418 	read_lock(&mrt_lock);
419 	return mr_vif_seq_start(seq, pos);
420 }
421 
422 static void ip6mr_vif_seq_stop(struct seq_file *seq, void *v)
423 	__releases(mrt_lock)
424 {
425 	read_unlock(&mrt_lock);
426 }
427 
428 static int ip6mr_vif_seq_show(struct seq_file *seq, void *v)
429 {
430 	struct mr_vif_iter *iter = seq->private;
431 	struct mr_table *mrt = iter->mrt;
432 
433 	if (v == SEQ_START_TOKEN) {
434 		seq_puts(seq,
435 			 "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags\n");
436 	} else {
437 		const struct vif_device *vif = v;
438 		const char *name = vif->dev ? vif->dev->name : "none";
439 
440 		seq_printf(seq,
441 			   "%2td %-10s %8ld %7ld  %8ld %7ld %05X\n",
442 			   vif - mrt->vif_table,
443 			   name, vif->bytes_in, vif->pkt_in,
444 			   vif->bytes_out, vif->pkt_out,
445 			   vif->flags);
446 	}
447 	return 0;
448 }
449 
450 static const struct seq_operations ip6mr_vif_seq_ops = {
451 	.start = ip6mr_vif_seq_start,
452 	.next  = mr_vif_seq_next,
453 	.stop  = ip6mr_vif_seq_stop,
454 	.show  = ip6mr_vif_seq_show,
455 };
456 
457 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
458 {
459 	struct net *net = seq_file_net(seq);
460 	struct mr_table *mrt;
461 
462 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
463 	if (!mrt)
464 		return ERR_PTR(-ENOENT);
465 
466 	return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
467 }
468 
469 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
470 {
471 	int n;
472 
473 	if (v == SEQ_START_TOKEN) {
474 		seq_puts(seq,
475 			 "Group                            "
476 			 "Origin                           "
477 			 "Iif      Pkts  Bytes     Wrong  Oifs\n");
478 	} else {
479 		const struct mfc6_cache *mfc = v;
480 		const struct mr_mfc_iter *it = seq->private;
481 		struct mr_table *mrt = it->mrt;
482 
483 		seq_printf(seq, "%pI6 %pI6 %-3hd",
484 			   &mfc->mf6c_mcastgrp, &mfc->mf6c_origin,
485 			   mfc->_c.mfc_parent);
486 
487 		if (it->cache != &mrt->mfc_unres_queue) {
488 			seq_printf(seq, " %8lu %8lu %8lu",
489 				   mfc->_c.mfc_un.res.pkt,
490 				   mfc->_c.mfc_un.res.bytes,
491 				   mfc->_c.mfc_un.res.wrong_if);
492 			for (n = mfc->_c.mfc_un.res.minvif;
493 			     n < mfc->_c.mfc_un.res.maxvif; n++) {
494 				if (VIF_EXISTS(mrt, n) &&
495 				    mfc->_c.mfc_un.res.ttls[n] < 255)
496 					seq_printf(seq,
497 						   " %2d:%-3d", n,
498 						   mfc->_c.mfc_un.res.ttls[n]);
499 			}
500 		} else {
501 			/* unresolved mfc_caches don't contain
502 			 * pkt, bytes and wrong_if values
503 			 */
504 			seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
505 		}
506 		seq_putc(seq, '\n');
507 	}
508 	return 0;
509 }
510 
511 static const struct seq_operations ipmr_mfc_seq_ops = {
512 	.start = ipmr_mfc_seq_start,
513 	.next  = mr_mfc_seq_next,
514 	.stop  = mr_mfc_seq_stop,
515 	.show  = ipmr_mfc_seq_show,
516 };
517 #endif
518 
519 #ifdef CONFIG_IPV6_PIMSM_V2
520 
521 static int pim6_rcv(struct sk_buff *skb)
522 {
523 	struct pimreghdr *pim;
524 	struct ipv6hdr   *encap;
525 	struct net_device  *reg_dev = NULL;
526 	struct net *net = dev_net(skb->dev);
527 	struct mr_table *mrt;
528 	struct flowi6 fl6 = {
529 		.flowi6_iif	= skb->dev->ifindex,
530 		.flowi6_mark	= skb->mark,
531 	};
532 	int reg_vif_num;
533 
534 	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
535 		goto drop;
536 
537 	pim = (struct pimreghdr *)skb_transport_header(skb);
538 	if (pim->type != ((PIM_VERSION << 4) | PIM_TYPE_REGISTER) ||
539 	    (pim->flags & PIM_NULL_REGISTER) ||
540 	    (csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
541 			     sizeof(*pim), IPPROTO_PIM,
542 			     csum_partial((void *)pim, sizeof(*pim), 0)) &&
543 	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
544 		goto drop;
545 
546 	/* check if the inner packet is destined to mcast group */
547 	encap = (struct ipv6hdr *)(skb_transport_header(skb) +
548 				   sizeof(*pim));
549 
550 	if (!ipv6_addr_is_multicast(&encap->daddr) ||
551 	    encap->payload_len == 0 ||
552 	    ntohs(encap->payload_len) + sizeof(*pim) > skb->len)
553 		goto drop;
554 
555 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
556 		goto drop;
557 	reg_vif_num = mrt->mroute_reg_vif_num;
558 
559 	read_lock(&mrt_lock);
560 	if (reg_vif_num >= 0)
561 		reg_dev = mrt->vif_table[reg_vif_num].dev;
562 	if (reg_dev)
563 		dev_hold(reg_dev);
564 	read_unlock(&mrt_lock);
565 
566 	if (!reg_dev)
567 		goto drop;
568 
569 	skb->mac_header = skb->network_header;
570 	skb_pull(skb, (u8 *)encap - skb->data);
571 	skb_reset_network_header(skb);
572 	skb->protocol = htons(ETH_P_IPV6);
573 	skb->ip_summed = CHECKSUM_NONE;
574 
575 	skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
576 
577 	netif_rx(skb);
578 
579 	dev_put(reg_dev);
580 	return 0;
581  drop:
582 	kfree_skb(skb);
583 	return 0;
584 }
585 
586 static const struct inet6_protocol pim6_protocol = {
587 	.handler	=	pim6_rcv,
588 };
589 
590 /* Service routines creating virtual interfaces: PIMREG */
591 
592 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb,
593 				      struct net_device *dev)
594 {
595 	struct net *net = dev_net(dev);
596 	struct mr_table *mrt;
597 	struct flowi6 fl6 = {
598 		.flowi6_oif	= dev->ifindex,
599 		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
600 		.flowi6_mark	= skb->mark,
601 	};
602 
603 	if (!pskb_inet_may_pull(skb))
604 		goto tx_err;
605 
606 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
607 		goto tx_err;
608 
609 	read_lock(&mrt_lock);
610 	dev->stats.tx_bytes += skb->len;
611 	dev->stats.tx_packets++;
612 	ip6mr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, MRT6MSG_WHOLEPKT);
613 	read_unlock(&mrt_lock);
614 	kfree_skb(skb);
615 	return NETDEV_TX_OK;
616 
617 tx_err:
618 	dev->stats.tx_errors++;
619 	kfree_skb(skb);
620 	return NETDEV_TX_OK;
621 }
622 
623 static int reg_vif_get_iflink(const struct net_device *dev)
624 {
625 	return 0;
626 }
627 
628 static const struct net_device_ops reg_vif_netdev_ops = {
629 	.ndo_start_xmit	= reg_vif_xmit,
630 	.ndo_get_iflink = reg_vif_get_iflink,
631 };
632 
633 static void reg_vif_setup(struct net_device *dev)
634 {
635 	dev->type		= ARPHRD_PIMREG;
636 	dev->mtu		= 1500 - sizeof(struct ipv6hdr) - 8;
637 	dev->flags		= IFF_NOARP;
638 	dev->netdev_ops		= &reg_vif_netdev_ops;
639 	dev->needs_free_netdev	= true;
640 	dev->features		|= NETIF_F_NETNS_LOCAL;
641 }
642 
643 static struct net_device *ip6mr_reg_vif(struct net *net, struct mr_table *mrt)
644 {
645 	struct net_device *dev;
646 	char name[IFNAMSIZ];
647 
648 	if (mrt->id == RT6_TABLE_DFLT)
649 		sprintf(name, "pim6reg");
650 	else
651 		sprintf(name, "pim6reg%u", mrt->id);
652 
653 	dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
654 	if (!dev)
655 		return NULL;
656 
657 	dev_net_set(dev, net);
658 
659 	if (register_netdevice(dev)) {
660 		free_netdev(dev);
661 		return NULL;
662 	}
663 
664 	if (dev_open(dev, NULL))
665 		goto failure;
666 
667 	dev_hold(dev);
668 	return dev;
669 
670 failure:
671 	unregister_netdevice(dev);
672 	return NULL;
673 }
674 #endif
675 
676 static int call_ip6mr_vif_entry_notifiers(struct net *net,
677 					  enum fib_event_type event_type,
678 					  struct vif_device *vif,
679 					  mifi_t vif_index, u32 tb_id)
680 {
681 	return mr_call_vif_notifiers(net, RTNL_FAMILY_IP6MR, event_type,
682 				     vif, vif_index, tb_id,
683 				     &net->ipv6.ipmr_seq);
684 }
685 
686 static int call_ip6mr_mfc_entry_notifiers(struct net *net,
687 					  enum fib_event_type event_type,
688 					  struct mfc6_cache *mfc, u32 tb_id)
689 {
690 	return mr_call_mfc_notifiers(net, RTNL_FAMILY_IP6MR, event_type,
691 				     &mfc->_c, tb_id, &net->ipv6.ipmr_seq);
692 }
693 
694 /* Delete a VIF entry */
695 static int mif6_delete(struct mr_table *mrt, int vifi, int notify,
696 		       struct list_head *head)
697 {
698 	struct vif_device *v;
699 	struct net_device *dev;
700 	struct inet6_dev *in6_dev;
701 
702 	if (vifi < 0 || vifi >= mrt->maxvif)
703 		return -EADDRNOTAVAIL;
704 
705 	v = &mrt->vif_table[vifi];
706 
707 	if (VIF_EXISTS(mrt, vifi))
708 		call_ip6mr_vif_entry_notifiers(read_pnet(&mrt->net),
709 					       FIB_EVENT_VIF_DEL, v, vifi,
710 					       mrt->id);
711 
712 	write_lock_bh(&mrt_lock);
713 	dev = v->dev;
714 	v->dev = NULL;
715 
716 	if (!dev) {
717 		write_unlock_bh(&mrt_lock);
718 		return -EADDRNOTAVAIL;
719 	}
720 
721 #ifdef CONFIG_IPV6_PIMSM_V2
722 	if (vifi == mrt->mroute_reg_vif_num)
723 		mrt->mroute_reg_vif_num = -1;
724 #endif
725 
726 	if (vifi + 1 == mrt->maxvif) {
727 		int tmp;
728 		for (tmp = vifi - 1; tmp >= 0; tmp--) {
729 			if (VIF_EXISTS(mrt, tmp))
730 				break;
731 		}
732 		mrt->maxvif = tmp + 1;
733 	}
734 
735 	write_unlock_bh(&mrt_lock);
736 
737 	dev_set_allmulti(dev, -1);
738 
739 	in6_dev = __in6_dev_get(dev);
740 	if (in6_dev) {
741 		in6_dev->cnf.mc_forwarding--;
742 		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
743 					     NETCONFA_MC_FORWARDING,
744 					     dev->ifindex, &in6_dev->cnf);
745 	}
746 
747 	if ((v->flags & MIFF_REGISTER) && !notify)
748 		unregister_netdevice_queue(dev, head);
749 
750 	dev_put(dev);
751 	return 0;
752 }
753 
754 static inline void ip6mr_cache_free_rcu(struct rcu_head *head)
755 {
756 	struct mr_mfc *c = container_of(head, struct mr_mfc, rcu);
757 
758 	kmem_cache_free(mrt_cachep, (struct mfc6_cache *)c);
759 }
760 
761 static inline void ip6mr_cache_free(struct mfc6_cache *c)
762 {
763 	call_rcu(&c->_c.rcu, ip6mr_cache_free_rcu);
764 }
765 
766 /* Destroy an unresolved cache entry, killing queued skbs
767    and reporting error to netlink readers.
768  */
769 
770 static void ip6mr_destroy_unres(struct mr_table *mrt, struct mfc6_cache *c)
771 {
772 	struct net *net = read_pnet(&mrt->net);
773 	struct sk_buff *skb;
774 
775 	atomic_dec(&mrt->cache_resolve_queue_len);
776 
777 	while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved)) != NULL) {
778 		if (ipv6_hdr(skb)->version == 0) {
779 			struct nlmsghdr *nlh = skb_pull(skb,
780 							sizeof(struct ipv6hdr));
781 			nlh->nlmsg_type = NLMSG_ERROR;
782 			nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
783 			skb_trim(skb, nlh->nlmsg_len);
784 			((struct nlmsgerr *)nlmsg_data(nlh))->error = -ETIMEDOUT;
785 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
786 		} else
787 			kfree_skb(skb);
788 	}
789 
790 	ip6mr_cache_free(c);
791 }
792 
793 
794 /* Timer process for all the unresolved queue. */
795 
796 static void ipmr_do_expire_process(struct mr_table *mrt)
797 {
798 	unsigned long now = jiffies;
799 	unsigned long expires = 10 * HZ;
800 	struct mr_mfc *c, *next;
801 
802 	list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
803 		if (time_after(c->mfc_un.unres.expires, now)) {
804 			/* not yet... */
805 			unsigned long interval = c->mfc_un.unres.expires - now;
806 			if (interval < expires)
807 				expires = interval;
808 			continue;
809 		}
810 
811 		list_del(&c->list);
812 		mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
813 		ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
814 	}
815 
816 	if (!list_empty(&mrt->mfc_unres_queue))
817 		mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
818 }
819 
820 static void ipmr_expire_process(struct timer_list *t)
821 {
822 	struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
823 
824 	if (!spin_trylock(&mfc_unres_lock)) {
825 		mod_timer(&mrt->ipmr_expire_timer, jiffies + 1);
826 		return;
827 	}
828 
829 	if (!list_empty(&mrt->mfc_unres_queue))
830 		ipmr_do_expire_process(mrt);
831 
832 	spin_unlock(&mfc_unres_lock);
833 }
834 
835 /* Fill oifs list. It is called under write locked mrt_lock. */
836 
837 static void ip6mr_update_thresholds(struct mr_table *mrt,
838 				    struct mr_mfc *cache,
839 				    unsigned char *ttls)
840 {
841 	int vifi;
842 
843 	cache->mfc_un.res.minvif = MAXMIFS;
844 	cache->mfc_un.res.maxvif = 0;
845 	memset(cache->mfc_un.res.ttls, 255, MAXMIFS);
846 
847 	for (vifi = 0; vifi < mrt->maxvif; vifi++) {
848 		if (VIF_EXISTS(mrt, vifi) &&
849 		    ttls[vifi] && ttls[vifi] < 255) {
850 			cache->mfc_un.res.ttls[vifi] = ttls[vifi];
851 			if (cache->mfc_un.res.minvif > vifi)
852 				cache->mfc_un.res.minvif = vifi;
853 			if (cache->mfc_un.res.maxvif <= vifi)
854 				cache->mfc_un.res.maxvif = vifi + 1;
855 		}
856 	}
857 	cache->mfc_un.res.lastuse = jiffies;
858 }
859 
860 static int mif6_add(struct net *net, struct mr_table *mrt,
861 		    struct mif6ctl *vifc, int mrtsock)
862 {
863 	int vifi = vifc->mif6c_mifi;
864 	struct vif_device *v = &mrt->vif_table[vifi];
865 	struct net_device *dev;
866 	struct inet6_dev *in6_dev;
867 	int err;
868 
869 	/* Is vif busy ? */
870 	if (VIF_EXISTS(mrt, vifi))
871 		return -EADDRINUSE;
872 
873 	switch (vifc->mif6c_flags) {
874 #ifdef CONFIG_IPV6_PIMSM_V2
875 	case MIFF_REGISTER:
876 		/*
877 		 * Special Purpose VIF in PIM
878 		 * All the packets will be sent to the daemon
879 		 */
880 		if (mrt->mroute_reg_vif_num >= 0)
881 			return -EADDRINUSE;
882 		dev = ip6mr_reg_vif(net, mrt);
883 		if (!dev)
884 			return -ENOBUFS;
885 		err = dev_set_allmulti(dev, 1);
886 		if (err) {
887 			unregister_netdevice(dev);
888 			dev_put(dev);
889 			return err;
890 		}
891 		break;
892 #endif
893 	case 0:
894 		dev = dev_get_by_index(net, vifc->mif6c_pifi);
895 		if (!dev)
896 			return -EADDRNOTAVAIL;
897 		err = dev_set_allmulti(dev, 1);
898 		if (err) {
899 			dev_put(dev);
900 			return err;
901 		}
902 		break;
903 	default:
904 		return -EINVAL;
905 	}
906 
907 	in6_dev = __in6_dev_get(dev);
908 	if (in6_dev) {
909 		in6_dev->cnf.mc_forwarding++;
910 		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
911 					     NETCONFA_MC_FORWARDING,
912 					     dev->ifindex, &in6_dev->cnf);
913 	}
914 
915 	/* Fill in the VIF structures */
916 	vif_device_init(v, dev, vifc->vifc_rate_limit, vifc->vifc_threshold,
917 			vifc->mif6c_flags | (!mrtsock ? VIFF_STATIC : 0),
918 			MIFF_REGISTER);
919 
920 	/* And finish update writing critical data */
921 	write_lock_bh(&mrt_lock);
922 	v->dev = dev;
923 #ifdef CONFIG_IPV6_PIMSM_V2
924 	if (v->flags & MIFF_REGISTER)
925 		mrt->mroute_reg_vif_num = vifi;
926 #endif
927 	if (vifi + 1 > mrt->maxvif)
928 		mrt->maxvif = vifi + 1;
929 	write_unlock_bh(&mrt_lock);
930 	call_ip6mr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD,
931 				       v, vifi, mrt->id);
932 	return 0;
933 }
934 
935 static struct mfc6_cache *ip6mr_cache_find(struct mr_table *mrt,
936 					   const struct in6_addr *origin,
937 					   const struct in6_addr *mcastgrp)
938 {
939 	struct mfc6_cache_cmp_arg arg = {
940 		.mf6c_origin = *origin,
941 		.mf6c_mcastgrp = *mcastgrp,
942 	};
943 
944 	return mr_mfc_find(mrt, &arg);
945 }
946 
947 /* Look for a (*,G) entry */
948 static struct mfc6_cache *ip6mr_cache_find_any(struct mr_table *mrt,
949 					       struct in6_addr *mcastgrp,
950 					       mifi_t mifi)
951 {
952 	struct mfc6_cache_cmp_arg arg = {
953 		.mf6c_origin = in6addr_any,
954 		.mf6c_mcastgrp = *mcastgrp,
955 	};
956 
957 	if (ipv6_addr_any(mcastgrp))
958 		return mr_mfc_find_any_parent(mrt, mifi);
959 	return mr_mfc_find_any(mrt, mifi, &arg);
960 }
961 
962 /* Look for a (S,G,iif) entry if parent != -1 */
963 static struct mfc6_cache *
964 ip6mr_cache_find_parent(struct mr_table *mrt,
965 			const struct in6_addr *origin,
966 			const struct in6_addr *mcastgrp,
967 			int parent)
968 {
969 	struct mfc6_cache_cmp_arg arg = {
970 		.mf6c_origin = *origin,
971 		.mf6c_mcastgrp = *mcastgrp,
972 	};
973 
974 	return mr_mfc_find_parent(mrt, &arg, parent);
975 }
976 
977 /* Allocate a multicast cache entry */
978 static struct mfc6_cache *ip6mr_cache_alloc(void)
979 {
980 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
981 	if (!c)
982 		return NULL;
983 	c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
984 	c->_c.mfc_un.res.minvif = MAXMIFS;
985 	c->_c.free = ip6mr_cache_free_rcu;
986 	refcount_set(&c->_c.mfc_un.res.refcount, 1);
987 	return c;
988 }
989 
990 static struct mfc6_cache *ip6mr_cache_alloc_unres(void)
991 {
992 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
993 	if (!c)
994 		return NULL;
995 	skb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
996 	c->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
997 	return c;
998 }
999 
1000 /*
1001  *	A cache entry has gone into a resolved state from queued
1002  */
1003 
1004 static void ip6mr_cache_resolve(struct net *net, struct mr_table *mrt,
1005 				struct mfc6_cache *uc, struct mfc6_cache *c)
1006 {
1007 	struct sk_buff *skb;
1008 
1009 	/*
1010 	 *	Play the pending entries through our router
1011 	 */
1012 
1013 	while ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
1014 		if (ipv6_hdr(skb)->version == 0) {
1015 			struct nlmsghdr *nlh = skb_pull(skb,
1016 							sizeof(struct ipv6hdr));
1017 
1018 			if (mr_fill_mroute(mrt, skb, &c->_c,
1019 					   nlmsg_data(nlh)) > 0) {
1020 				nlh->nlmsg_len = skb_tail_pointer(skb) - (u8 *)nlh;
1021 			} else {
1022 				nlh->nlmsg_type = NLMSG_ERROR;
1023 				nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
1024 				skb_trim(skb, nlh->nlmsg_len);
1025 				((struct nlmsgerr *)nlmsg_data(nlh))->error = -EMSGSIZE;
1026 			}
1027 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
1028 		} else
1029 			ip6_mr_forward(net, mrt, skb->dev, skb, c);
1030 	}
1031 }
1032 
1033 /*
1034  *	Bounce a cache query up to pim6sd and netlink.
1035  *
1036  *	Called under mrt_lock.
1037  */
1038 
1039 static int ip6mr_cache_report(struct mr_table *mrt, struct sk_buff *pkt,
1040 			      mifi_t mifi, int assert)
1041 {
1042 	struct sock *mroute6_sk;
1043 	struct sk_buff *skb;
1044 	struct mrt6msg *msg;
1045 	int ret;
1046 
1047 #ifdef CONFIG_IPV6_PIMSM_V2
1048 	if (assert == MRT6MSG_WHOLEPKT)
1049 		skb = skb_realloc_headroom(pkt, -skb_network_offset(pkt)
1050 						+sizeof(*msg));
1051 	else
1052 #endif
1053 		skb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(*msg), GFP_ATOMIC);
1054 
1055 	if (!skb)
1056 		return -ENOBUFS;
1057 
1058 	/* I suppose that internal messages
1059 	 * do not require checksums */
1060 
1061 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1062 
1063 #ifdef CONFIG_IPV6_PIMSM_V2
1064 	if (assert == MRT6MSG_WHOLEPKT) {
1065 		/* Ugly, but we have no choice with this interface.
1066 		   Duplicate old header, fix length etc.
1067 		   And all this only to mangle msg->im6_msgtype and
1068 		   to set msg->im6_mbz to "mbz" :-)
1069 		 */
1070 		skb_push(skb, -skb_network_offset(pkt));
1071 
1072 		skb_push(skb, sizeof(*msg));
1073 		skb_reset_transport_header(skb);
1074 		msg = (struct mrt6msg *)skb_transport_header(skb);
1075 		msg->im6_mbz = 0;
1076 		msg->im6_msgtype = MRT6MSG_WHOLEPKT;
1077 		msg->im6_mif = mrt->mroute_reg_vif_num;
1078 		msg->im6_pad = 0;
1079 		msg->im6_src = ipv6_hdr(pkt)->saddr;
1080 		msg->im6_dst = ipv6_hdr(pkt)->daddr;
1081 
1082 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1083 	} else
1084 #endif
1085 	{
1086 	/*
1087 	 *	Copy the IP header
1088 	 */
1089 
1090 	skb_put(skb, sizeof(struct ipv6hdr));
1091 	skb_reset_network_header(skb);
1092 	skb_copy_to_linear_data(skb, ipv6_hdr(pkt), sizeof(struct ipv6hdr));
1093 
1094 	/*
1095 	 *	Add our header
1096 	 */
1097 	skb_put(skb, sizeof(*msg));
1098 	skb_reset_transport_header(skb);
1099 	msg = (struct mrt6msg *)skb_transport_header(skb);
1100 
1101 	msg->im6_mbz = 0;
1102 	msg->im6_msgtype = assert;
1103 	msg->im6_mif = mifi;
1104 	msg->im6_pad = 0;
1105 	msg->im6_src = ipv6_hdr(pkt)->saddr;
1106 	msg->im6_dst = ipv6_hdr(pkt)->daddr;
1107 
1108 	skb_dst_set(skb, dst_clone(skb_dst(pkt)));
1109 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1110 	}
1111 
1112 	rcu_read_lock();
1113 	mroute6_sk = rcu_dereference(mrt->mroute_sk);
1114 	if (!mroute6_sk) {
1115 		rcu_read_unlock();
1116 		kfree_skb(skb);
1117 		return -EINVAL;
1118 	}
1119 
1120 	mrt6msg_netlink_event(mrt, skb);
1121 
1122 	/* Deliver to user space multicast routing algorithms */
1123 	ret = sock_queue_rcv_skb(mroute6_sk, skb);
1124 	rcu_read_unlock();
1125 	if (ret < 0) {
1126 		net_warn_ratelimited("mroute6: pending queue full, dropping entries\n");
1127 		kfree_skb(skb);
1128 	}
1129 
1130 	return ret;
1131 }
1132 
1133 /* Queue a packet for resolution. It gets locked cache entry! */
1134 static int ip6mr_cache_unresolved(struct mr_table *mrt, mifi_t mifi,
1135 				  struct sk_buff *skb, struct net_device *dev)
1136 {
1137 	struct mfc6_cache *c;
1138 	bool found = false;
1139 	int err;
1140 
1141 	spin_lock_bh(&mfc_unres_lock);
1142 	list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
1143 		if (ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&
1144 		    ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr)) {
1145 			found = true;
1146 			break;
1147 		}
1148 	}
1149 
1150 	if (!found) {
1151 		/*
1152 		 *	Create a new entry if allowable
1153 		 */
1154 
1155 		c = ip6mr_cache_alloc_unres();
1156 		if (!c) {
1157 			spin_unlock_bh(&mfc_unres_lock);
1158 
1159 			kfree_skb(skb);
1160 			return -ENOBUFS;
1161 		}
1162 
1163 		/* Fill in the new cache entry */
1164 		c->_c.mfc_parent = -1;
1165 		c->mf6c_origin = ipv6_hdr(skb)->saddr;
1166 		c->mf6c_mcastgrp = ipv6_hdr(skb)->daddr;
1167 
1168 		/*
1169 		 *	Reflect first query at pim6sd
1170 		 */
1171 		err = ip6mr_cache_report(mrt, skb, mifi, MRT6MSG_NOCACHE);
1172 		if (err < 0) {
1173 			/* If the report failed throw the cache entry
1174 			   out - Brad Parker
1175 			 */
1176 			spin_unlock_bh(&mfc_unres_lock);
1177 
1178 			ip6mr_cache_free(c);
1179 			kfree_skb(skb);
1180 			return err;
1181 		}
1182 
1183 		atomic_inc(&mrt->cache_resolve_queue_len);
1184 		list_add(&c->_c.list, &mrt->mfc_unres_queue);
1185 		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1186 
1187 		ipmr_do_expire_process(mrt);
1188 	}
1189 
1190 	/* See if we can append the packet */
1191 	if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
1192 		kfree_skb(skb);
1193 		err = -ENOBUFS;
1194 	} else {
1195 		if (dev) {
1196 			skb->dev = dev;
1197 			skb->skb_iif = dev->ifindex;
1198 		}
1199 		skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
1200 		err = 0;
1201 	}
1202 
1203 	spin_unlock_bh(&mfc_unres_lock);
1204 	return err;
1205 }
1206 
1207 /*
1208  *	MFC6 cache manipulation by user space
1209  */
1210 
1211 static int ip6mr_mfc_delete(struct mr_table *mrt, struct mf6cctl *mfc,
1212 			    int parent)
1213 {
1214 	struct mfc6_cache *c;
1215 
1216 	/* The entries are added/deleted only under RTNL */
1217 	rcu_read_lock();
1218 	c = ip6mr_cache_find_parent(mrt, &mfc->mf6cc_origin.sin6_addr,
1219 				    &mfc->mf6cc_mcastgrp.sin6_addr, parent);
1220 	rcu_read_unlock();
1221 	if (!c)
1222 		return -ENOENT;
1223 	rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ip6mr_rht_params);
1224 	list_del_rcu(&c->_c.list);
1225 
1226 	call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
1227 				       FIB_EVENT_ENTRY_DEL, c, mrt->id);
1228 	mr6_netlink_event(mrt, c, RTM_DELROUTE);
1229 	mr_cache_put(&c->_c);
1230 	return 0;
1231 }
1232 
1233 static int ip6mr_device_event(struct notifier_block *this,
1234 			      unsigned long event, void *ptr)
1235 {
1236 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1237 	struct net *net = dev_net(dev);
1238 	struct mr_table *mrt;
1239 	struct vif_device *v;
1240 	int ct;
1241 
1242 	if (event != NETDEV_UNREGISTER)
1243 		return NOTIFY_DONE;
1244 
1245 	ip6mr_for_each_table(mrt, net) {
1246 		v = &mrt->vif_table[0];
1247 		for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1248 			if (v->dev == dev)
1249 				mif6_delete(mrt, ct, 1, NULL);
1250 		}
1251 	}
1252 
1253 	return NOTIFY_DONE;
1254 }
1255 
1256 static unsigned int ip6mr_seq_read(struct net *net)
1257 {
1258 	ASSERT_RTNL();
1259 
1260 	return net->ipv6.ipmr_seq + ip6mr_rules_seq_read(net);
1261 }
1262 
1263 static int ip6mr_dump(struct net *net, struct notifier_block *nb,
1264 		      struct netlink_ext_ack *extack)
1265 {
1266 	return mr_dump(net, nb, RTNL_FAMILY_IP6MR, ip6mr_rules_dump,
1267 		       ip6mr_mr_table_iter, &mrt_lock, extack);
1268 }
1269 
1270 static struct notifier_block ip6_mr_notifier = {
1271 	.notifier_call = ip6mr_device_event
1272 };
1273 
1274 static const struct fib_notifier_ops ip6mr_notifier_ops_template = {
1275 	.family		= RTNL_FAMILY_IP6MR,
1276 	.fib_seq_read	= ip6mr_seq_read,
1277 	.fib_dump	= ip6mr_dump,
1278 	.owner		= THIS_MODULE,
1279 };
1280 
1281 static int __net_init ip6mr_notifier_init(struct net *net)
1282 {
1283 	struct fib_notifier_ops *ops;
1284 
1285 	net->ipv6.ipmr_seq = 0;
1286 
1287 	ops = fib_notifier_ops_register(&ip6mr_notifier_ops_template, net);
1288 	if (IS_ERR(ops))
1289 		return PTR_ERR(ops);
1290 
1291 	net->ipv6.ip6mr_notifier_ops = ops;
1292 
1293 	return 0;
1294 }
1295 
1296 static void __net_exit ip6mr_notifier_exit(struct net *net)
1297 {
1298 	fib_notifier_ops_unregister(net->ipv6.ip6mr_notifier_ops);
1299 	net->ipv6.ip6mr_notifier_ops = NULL;
1300 }
1301 
1302 /* Setup for IP multicast routing */
1303 static int __net_init ip6mr_net_init(struct net *net)
1304 {
1305 	int err;
1306 
1307 	err = ip6mr_notifier_init(net);
1308 	if (err)
1309 		return err;
1310 
1311 	err = ip6mr_rules_init(net);
1312 	if (err < 0)
1313 		goto ip6mr_rules_fail;
1314 
1315 #ifdef CONFIG_PROC_FS
1316 	err = -ENOMEM;
1317 	if (!proc_create_net("ip6_mr_vif", 0, net->proc_net, &ip6mr_vif_seq_ops,
1318 			sizeof(struct mr_vif_iter)))
1319 		goto proc_vif_fail;
1320 	if (!proc_create_net("ip6_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
1321 			sizeof(struct mr_mfc_iter)))
1322 		goto proc_cache_fail;
1323 #endif
1324 
1325 	return 0;
1326 
1327 #ifdef CONFIG_PROC_FS
1328 proc_cache_fail:
1329 	remove_proc_entry("ip6_mr_vif", net->proc_net);
1330 proc_vif_fail:
1331 	ip6mr_rules_exit(net);
1332 #endif
1333 ip6mr_rules_fail:
1334 	ip6mr_notifier_exit(net);
1335 	return err;
1336 }
1337 
1338 static void __net_exit ip6mr_net_exit(struct net *net)
1339 {
1340 #ifdef CONFIG_PROC_FS
1341 	remove_proc_entry("ip6_mr_cache", net->proc_net);
1342 	remove_proc_entry("ip6_mr_vif", net->proc_net);
1343 #endif
1344 	ip6mr_rules_exit(net);
1345 	ip6mr_notifier_exit(net);
1346 }
1347 
1348 static struct pernet_operations ip6mr_net_ops = {
1349 	.init = ip6mr_net_init,
1350 	.exit = ip6mr_net_exit,
1351 };
1352 
1353 int __init ip6_mr_init(void)
1354 {
1355 	int err;
1356 
1357 	mrt_cachep = kmem_cache_create("ip6_mrt_cache",
1358 				       sizeof(struct mfc6_cache),
1359 				       0, SLAB_HWCACHE_ALIGN,
1360 				       NULL);
1361 	if (!mrt_cachep)
1362 		return -ENOMEM;
1363 
1364 	err = register_pernet_subsys(&ip6mr_net_ops);
1365 	if (err)
1366 		goto reg_pernet_fail;
1367 
1368 	err = register_netdevice_notifier(&ip6_mr_notifier);
1369 	if (err)
1370 		goto reg_notif_fail;
1371 #ifdef CONFIG_IPV6_PIMSM_V2
1372 	if (inet6_add_protocol(&pim6_protocol, IPPROTO_PIM) < 0) {
1373 		pr_err("%s: can't add PIM protocol\n", __func__);
1374 		err = -EAGAIN;
1375 		goto add_proto_fail;
1376 	}
1377 #endif
1378 	err = rtnl_register_module(THIS_MODULE, RTNL_FAMILY_IP6MR, RTM_GETROUTE,
1379 				   NULL, ip6mr_rtm_dumproute, 0);
1380 	if (err == 0)
1381 		return 0;
1382 
1383 #ifdef CONFIG_IPV6_PIMSM_V2
1384 	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
1385 add_proto_fail:
1386 	unregister_netdevice_notifier(&ip6_mr_notifier);
1387 #endif
1388 reg_notif_fail:
1389 	unregister_pernet_subsys(&ip6mr_net_ops);
1390 reg_pernet_fail:
1391 	kmem_cache_destroy(mrt_cachep);
1392 	return err;
1393 }
1394 
1395 void ip6_mr_cleanup(void)
1396 {
1397 	rtnl_unregister(RTNL_FAMILY_IP6MR, RTM_GETROUTE);
1398 #ifdef CONFIG_IPV6_PIMSM_V2
1399 	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
1400 #endif
1401 	unregister_netdevice_notifier(&ip6_mr_notifier);
1402 	unregister_pernet_subsys(&ip6mr_net_ops);
1403 	kmem_cache_destroy(mrt_cachep);
1404 }
1405 
1406 static int ip6mr_mfc_add(struct net *net, struct mr_table *mrt,
1407 			 struct mf6cctl *mfc, int mrtsock, int parent)
1408 {
1409 	unsigned char ttls[MAXMIFS];
1410 	struct mfc6_cache *uc, *c;
1411 	struct mr_mfc *_uc;
1412 	bool found;
1413 	int i, err;
1414 
1415 	if (mfc->mf6cc_parent >= MAXMIFS)
1416 		return -ENFILE;
1417 
1418 	memset(ttls, 255, MAXMIFS);
1419 	for (i = 0; i < MAXMIFS; i++) {
1420 		if (IF_ISSET(i, &mfc->mf6cc_ifset))
1421 			ttls[i] = 1;
1422 	}
1423 
1424 	/* The entries are added/deleted only under RTNL */
1425 	rcu_read_lock();
1426 	c = ip6mr_cache_find_parent(mrt, &mfc->mf6cc_origin.sin6_addr,
1427 				    &mfc->mf6cc_mcastgrp.sin6_addr, parent);
1428 	rcu_read_unlock();
1429 	if (c) {
1430 		write_lock_bh(&mrt_lock);
1431 		c->_c.mfc_parent = mfc->mf6cc_parent;
1432 		ip6mr_update_thresholds(mrt, &c->_c, ttls);
1433 		if (!mrtsock)
1434 			c->_c.mfc_flags |= MFC_STATIC;
1435 		write_unlock_bh(&mrt_lock);
1436 		call_ip6mr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE,
1437 					       c, mrt->id);
1438 		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1439 		return 0;
1440 	}
1441 
1442 	if (!ipv6_addr_any(&mfc->mf6cc_mcastgrp.sin6_addr) &&
1443 	    !ipv6_addr_is_multicast(&mfc->mf6cc_mcastgrp.sin6_addr))
1444 		return -EINVAL;
1445 
1446 	c = ip6mr_cache_alloc();
1447 	if (!c)
1448 		return -ENOMEM;
1449 
1450 	c->mf6c_origin = mfc->mf6cc_origin.sin6_addr;
1451 	c->mf6c_mcastgrp = mfc->mf6cc_mcastgrp.sin6_addr;
1452 	c->_c.mfc_parent = mfc->mf6cc_parent;
1453 	ip6mr_update_thresholds(mrt, &c->_c, ttls);
1454 	if (!mrtsock)
1455 		c->_c.mfc_flags |= MFC_STATIC;
1456 
1457 	err = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
1458 				  ip6mr_rht_params);
1459 	if (err) {
1460 		pr_err("ip6mr: rhtable insert error %d\n", err);
1461 		ip6mr_cache_free(c);
1462 		return err;
1463 	}
1464 	list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
1465 
1466 	/* Check to see if we resolved a queued list. If so we
1467 	 * need to send on the frames and tidy up.
1468 	 */
1469 	found = false;
1470 	spin_lock_bh(&mfc_unres_lock);
1471 	list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
1472 		uc = (struct mfc6_cache *)_uc;
1473 		if (ipv6_addr_equal(&uc->mf6c_origin, &c->mf6c_origin) &&
1474 		    ipv6_addr_equal(&uc->mf6c_mcastgrp, &c->mf6c_mcastgrp)) {
1475 			list_del(&_uc->list);
1476 			atomic_dec(&mrt->cache_resolve_queue_len);
1477 			found = true;
1478 			break;
1479 		}
1480 	}
1481 	if (list_empty(&mrt->mfc_unres_queue))
1482 		del_timer(&mrt->ipmr_expire_timer);
1483 	spin_unlock_bh(&mfc_unres_lock);
1484 
1485 	if (found) {
1486 		ip6mr_cache_resolve(net, mrt, uc, c);
1487 		ip6mr_cache_free(uc);
1488 	}
1489 	call_ip6mr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD,
1490 				       c, mrt->id);
1491 	mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1492 	return 0;
1493 }
1494 
1495 /*
1496  *	Close the multicast socket, and clear the vif tables etc
1497  */
1498 
1499 static void mroute_clean_tables(struct mr_table *mrt, int flags)
1500 {
1501 	struct mr_mfc *c, *tmp;
1502 	LIST_HEAD(list);
1503 	int i;
1504 
1505 	/* Shut down all active vif entries */
1506 	if (flags & (MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC)) {
1507 		for (i = 0; i < mrt->maxvif; i++) {
1508 			if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
1509 			     !(flags & MRT6_FLUSH_MIFS_STATIC)) ||
1510 			    (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT6_FLUSH_MIFS)))
1511 				continue;
1512 			mif6_delete(mrt, i, 0, &list);
1513 		}
1514 		unregister_netdevice_many(&list);
1515 	}
1516 
1517 	/* Wipe the cache */
1518 	if (flags & (MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC)) {
1519 		list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
1520 			if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT6_FLUSH_MFC_STATIC)) ||
1521 			    (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT6_FLUSH_MFC)))
1522 				continue;
1523 			rhltable_remove(&mrt->mfc_hash, &c->mnode, ip6mr_rht_params);
1524 			list_del_rcu(&c->list);
1525 			call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
1526 						       FIB_EVENT_ENTRY_DEL,
1527 						       (struct mfc6_cache *)c, mrt->id);
1528 			mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
1529 			mr_cache_put(c);
1530 		}
1531 	}
1532 
1533 	if (flags & MRT6_FLUSH_MFC) {
1534 		if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1535 			spin_lock_bh(&mfc_unres_lock);
1536 			list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
1537 				list_del(&c->list);
1538 				mr6_netlink_event(mrt, (struct mfc6_cache *)c,
1539 						  RTM_DELROUTE);
1540 				ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
1541 			}
1542 			spin_unlock_bh(&mfc_unres_lock);
1543 		}
1544 	}
1545 }
1546 
1547 static int ip6mr_sk_init(struct mr_table *mrt, struct sock *sk)
1548 {
1549 	int err = 0;
1550 	struct net *net = sock_net(sk);
1551 
1552 	rtnl_lock();
1553 	write_lock_bh(&mrt_lock);
1554 	if (rtnl_dereference(mrt->mroute_sk)) {
1555 		err = -EADDRINUSE;
1556 	} else {
1557 		rcu_assign_pointer(mrt->mroute_sk, sk);
1558 		sock_set_flag(sk, SOCK_RCU_FREE);
1559 		net->ipv6.devconf_all->mc_forwarding++;
1560 	}
1561 	write_unlock_bh(&mrt_lock);
1562 
1563 	if (!err)
1564 		inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
1565 					     NETCONFA_MC_FORWARDING,
1566 					     NETCONFA_IFINDEX_ALL,
1567 					     net->ipv6.devconf_all);
1568 	rtnl_unlock();
1569 
1570 	return err;
1571 }
1572 
1573 int ip6mr_sk_done(struct sock *sk)
1574 {
1575 	int err = -EACCES;
1576 	struct net *net = sock_net(sk);
1577 	struct mr_table *mrt;
1578 
1579 	if (sk->sk_type != SOCK_RAW ||
1580 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1581 		return err;
1582 
1583 	rtnl_lock();
1584 	ip6mr_for_each_table(mrt, net) {
1585 		if (sk == rtnl_dereference(mrt->mroute_sk)) {
1586 			write_lock_bh(&mrt_lock);
1587 			RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1588 			/* Note that mroute_sk had SOCK_RCU_FREE set,
1589 			 * so the RCU grace period before sk freeing
1590 			 * is guaranteed by sk_destruct()
1591 			 */
1592 			net->ipv6.devconf_all->mc_forwarding--;
1593 			write_unlock_bh(&mrt_lock);
1594 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
1595 						     NETCONFA_MC_FORWARDING,
1596 						     NETCONFA_IFINDEX_ALL,
1597 						     net->ipv6.devconf_all);
1598 
1599 			mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MFC);
1600 			err = 0;
1601 			break;
1602 		}
1603 	}
1604 	rtnl_unlock();
1605 
1606 	return err;
1607 }
1608 
1609 bool mroute6_is_socket(struct net *net, struct sk_buff *skb)
1610 {
1611 	struct mr_table *mrt;
1612 	struct flowi6 fl6 = {
1613 		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
1614 		.flowi6_oif	= skb->dev->ifindex,
1615 		.flowi6_mark	= skb->mark,
1616 	};
1617 
1618 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
1619 		return NULL;
1620 
1621 	return rcu_access_pointer(mrt->mroute_sk);
1622 }
1623 EXPORT_SYMBOL(mroute6_is_socket);
1624 
1625 /*
1626  *	Socket options and virtual interface manipulation. The whole
1627  *	virtual interface system is a complete heap, but unfortunately
1628  *	that's how BSD mrouted happens to think. Maybe one day with a proper
1629  *	MOSPF/PIM router set up we can clean this up.
1630  */
1631 
1632 int ip6_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval,
1633 			  unsigned int optlen)
1634 {
1635 	int ret, parent = 0;
1636 	struct mif6ctl vif;
1637 	struct mf6cctl mfc;
1638 	mifi_t mifi;
1639 	struct net *net = sock_net(sk);
1640 	struct mr_table *mrt;
1641 
1642 	if (sk->sk_type != SOCK_RAW ||
1643 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1644 		return -EOPNOTSUPP;
1645 
1646 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1647 	if (!mrt)
1648 		return -ENOENT;
1649 
1650 	if (optname != MRT6_INIT) {
1651 		if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1652 		    !ns_capable(net->user_ns, CAP_NET_ADMIN))
1653 			return -EACCES;
1654 	}
1655 
1656 	switch (optname) {
1657 	case MRT6_INIT:
1658 		if (optlen < sizeof(int))
1659 			return -EINVAL;
1660 
1661 		return ip6mr_sk_init(mrt, sk);
1662 
1663 	case MRT6_DONE:
1664 		return ip6mr_sk_done(sk);
1665 
1666 	case MRT6_ADD_MIF:
1667 		if (optlen < sizeof(vif))
1668 			return -EINVAL;
1669 		if (copy_from_sockptr(&vif, optval, sizeof(vif)))
1670 			return -EFAULT;
1671 		if (vif.mif6c_mifi >= MAXMIFS)
1672 			return -ENFILE;
1673 		rtnl_lock();
1674 		ret = mif6_add(net, mrt, &vif,
1675 			       sk == rtnl_dereference(mrt->mroute_sk));
1676 		rtnl_unlock();
1677 		return ret;
1678 
1679 	case MRT6_DEL_MIF:
1680 		if (optlen < sizeof(mifi_t))
1681 			return -EINVAL;
1682 		if (copy_from_sockptr(&mifi, optval, sizeof(mifi_t)))
1683 			return -EFAULT;
1684 		rtnl_lock();
1685 		ret = mif6_delete(mrt, mifi, 0, NULL);
1686 		rtnl_unlock();
1687 		return ret;
1688 
1689 	/*
1690 	 *	Manipulate the forwarding caches. These live
1691 	 *	in a sort of kernel/user symbiosis.
1692 	 */
1693 	case MRT6_ADD_MFC:
1694 	case MRT6_DEL_MFC:
1695 		parent = -1;
1696 		fallthrough;
1697 	case MRT6_ADD_MFC_PROXY:
1698 	case MRT6_DEL_MFC_PROXY:
1699 		if (optlen < sizeof(mfc))
1700 			return -EINVAL;
1701 		if (copy_from_sockptr(&mfc, optval, sizeof(mfc)))
1702 			return -EFAULT;
1703 		if (parent == 0)
1704 			parent = mfc.mf6cc_parent;
1705 		rtnl_lock();
1706 		if (optname == MRT6_DEL_MFC || optname == MRT6_DEL_MFC_PROXY)
1707 			ret = ip6mr_mfc_delete(mrt, &mfc, parent);
1708 		else
1709 			ret = ip6mr_mfc_add(net, mrt, &mfc,
1710 					    sk ==
1711 					    rtnl_dereference(mrt->mroute_sk),
1712 					    parent);
1713 		rtnl_unlock();
1714 		return ret;
1715 
1716 	case MRT6_FLUSH:
1717 	{
1718 		int flags;
1719 
1720 		if (optlen != sizeof(flags))
1721 			return -EINVAL;
1722 		if (copy_from_sockptr(&flags, optval, sizeof(flags)))
1723 			return -EFAULT;
1724 		rtnl_lock();
1725 		mroute_clean_tables(mrt, flags);
1726 		rtnl_unlock();
1727 		return 0;
1728 	}
1729 
1730 	/*
1731 	 *	Control PIM assert (to activate pim will activate assert)
1732 	 */
1733 	case MRT6_ASSERT:
1734 	{
1735 		int v;
1736 
1737 		if (optlen != sizeof(v))
1738 			return -EINVAL;
1739 		if (copy_from_sockptr(&v, optval, sizeof(v)))
1740 			return -EFAULT;
1741 		mrt->mroute_do_assert = v;
1742 		return 0;
1743 	}
1744 
1745 #ifdef CONFIG_IPV6_PIMSM_V2
1746 	case MRT6_PIM:
1747 	{
1748 		int v;
1749 
1750 		if (optlen != sizeof(v))
1751 			return -EINVAL;
1752 		if (copy_from_sockptr(&v, optval, sizeof(v)))
1753 			return -EFAULT;
1754 		v = !!v;
1755 		rtnl_lock();
1756 		ret = 0;
1757 		if (v != mrt->mroute_do_pim) {
1758 			mrt->mroute_do_pim = v;
1759 			mrt->mroute_do_assert = v;
1760 		}
1761 		rtnl_unlock();
1762 		return ret;
1763 	}
1764 
1765 #endif
1766 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
1767 	case MRT6_TABLE:
1768 	{
1769 		u32 v;
1770 
1771 		if (optlen != sizeof(u32))
1772 			return -EINVAL;
1773 		if (copy_from_sockptr(&v, optval, sizeof(v)))
1774 			return -EFAULT;
1775 		/* "pim6reg%u" should not exceed 16 bytes (IFNAMSIZ) */
1776 		if (v != RT_TABLE_DEFAULT && v >= 100000000)
1777 			return -EINVAL;
1778 		if (sk == rcu_access_pointer(mrt->mroute_sk))
1779 			return -EBUSY;
1780 
1781 		rtnl_lock();
1782 		ret = 0;
1783 		mrt = ip6mr_new_table(net, v);
1784 		if (IS_ERR(mrt))
1785 			ret = PTR_ERR(mrt);
1786 		else
1787 			raw6_sk(sk)->ip6mr_table = v;
1788 		rtnl_unlock();
1789 		return ret;
1790 	}
1791 #endif
1792 	/*
1793 	 *	Spurious command, or MRT6_VERSION which you cannot
1794 	 *	set.
1795 	 */
1796 	default:
1797 		return -ENOPROTOOPT;
1798 	}
1799 }
1800 
1801 /*
1802  *	Getsock opt support for the multicast routing system.
1803  */
1804 
1805 int ip6_mroute_getsockopt(struct sock *sk, int optname, char __user *optval,
1806 			  int __user *optlen)
1807 {
1808 	int olr;
1809 	int val;
1810 	struct net *net = sock_net(sk);
1811 	struct mr_table *mrt;
1812 
1813 	if (sk->sk_type != SOCK_RAW ||
1814 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1815 		return -EOPNOTSUPP;
1816 
1817 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1818 	if (!mrt)
1819 		return -ENOENT;
1820 
1821 	switch (optname) {
1822 	case MRT6_VERSION:
1823 		val = 0x0305;
1824 		break;
1825 #ifdef CONFIG_IPV6_PIMSM_V2
1826 	case MRT6_PIM:
1827 		val = mrt->mroute_do_pim;
1828 		break;
1829 #endif
1830 	case MRT6_ASSERT:
1831 		val = mrt->mroute_do_assert;
1832 		break;
1833 	default:
1834 		return -ENOPROTOOPT;
1835 	}
1836 
1837 	if (get_user(olr, optlen))
1838 		return -EFAULT;
1839 
1840 	olr = min_t(int, olr, sizeof(int));
1841 	if (olr < 0)
1842 		return -EINVAL;
1843 
1844 	if (put_user(olr, optlen))
1845 		return -EFAULT;
1846 	if (copy_to_user(optval, &val, olr))
1847 		return -EFAULT;
1848 	return 0;
1849 }
1850 
1851 /*
1852  *	The IP multicast ioctl support routines.
1853  */
1854 
1855 int ip6mr_ioctl(struct sock *sk, int cmd, void __user *arg)
1856 {
1857 	struct sioc_sg_req6 sr;
1858 	struct sioc_mif_req6 vr;
1859 	struct vif_device *vif;
1860 	struct mfc6_cache *c;
1861 	struct net *net = sock_net(sk);
1862 	struct mr_table *mrt;
1863 
1864 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1865 	if (!mrt)
1866 		return -ENOENT;
1867 
1868 	switch (cmd) {
1869 	case SIOCGETMIFCNT_IN6:
1870 		if (copy_from_user(&vr, arg, sizeof(vr)))
1871 			return -EFAULT;
1872 		if (vr.mifi >= mrt->maxvif)
1873 			return -EINVAL;
1874 		vr.mifi = array_index_nospec(vr.mifi, mrt->maxvif);
1875 		read_lock(&mrt_lock);
1876 		vif = &mrt->vif_table[vr.mifi];
1877 		if (VIF_EXISTS(mrt, vr.mifi)) {
1878 			vr.icount = vif->pkt_in;
1879 			vr.ocount = vif->pkt_out;
1880 			vr.ibytes = vif->bytes_in;
1881 			vr.obytes = vif->bytes_out;
1882 			read_unlock(&mrt_lock);
1883 
1884 			if (copy_to_user(arg, &vr, sizeof(vr)))
1885 				return -EFAULT;
1886 			return 0;
1887 		}
1888 		read_unlock(&mrt_lock);
1889 		return -EADDRNOTAVAIL;
1890 	case SIOCGETSGCNT_IN6:
1891 		if (copy_from_user(&sr, arg, sizeof(sr)))
1892 			return -EFAULT;
1893 
1894 		rcu_read_lock();
1895 		c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
1896 		if (c) {
1897 			sr.pktcnt = c->_c.mfc_un.res.pkt;
1898 			sr.bytecnt = c->_c.mfc_un.res.bytes;
1899 			sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1900 			rcu_read_unlock();
1901 
1902 			if (copy_to_user(arg, &sr, sizeof(sr)))
1903 				return -EFAULT;
1904 			return 0;
1905 		}
1906 		rcu_read_unlock();
1907 		return -EADDRNOTAVAIL;
1908 	default:
1909 		return -ENOIOCTLCMD;
1910 	}
1911 }
1912 
1913 #ifdef CONFIG_COMPAT
1914 struct compat_sioc_sg_req6 {
1915 	struct sockaddr_in6 src;
1916 	struct sockaddr_in6 grp;
1917 	compat_ulong_t pktcnt;
1918 	compat_ulong_t bytecnt;
1919 	compat_ulong_t wrong_if;
1920 };
1921 
1922 struct compat_sioc_mif_req6 {
1923 	mifi_t	mifi;
1924 	compat_ulong_t icount;
1925 	compat_ulong_t ocount;
1926 	compat_ulong_t ibytes;
1927 	compat_ulong_t obytes;
1928 };
1929 
1930 int ip6mr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1931 {
1932 	struct compat_sioc_sg_req6 sr;
1933 	struct compat_sioc_mif_req6 vr;
1934 	struct vif_device *vif;
1935 	struct mfc6_cache *c;
1936 	struct net *net = sock_net(sk);
1937 	struct mr_table *mrt;
1938 
1939 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1940 	if (!mrt)
1941 		return -ENOENT;
1942 
1943 	switch (cmd) {
1944 	case SIOCGETMIFCNT_IN6:
1945 		if (copy_from_user(&vr, arg, sizeof(vr)))
1946 			return -EFAULT;
1947 		if (vr.mifi >= mrt->maxvif)
1948 			return -EINVAL;
1949 		vr.mifi = array_index_nospec(vr.mifi, mrt->maxvif);
1950 		read_lock(&mrt_lock);
1951 		vif = &mrt->vif_table[vr.mifi];
1952 		if (VIF_EXISTS(mrt, vr.mifi)) {
1953 			vr.icount = vif->pkt_in;
1954 			vr.ocount = vif->pkt_out;
1955 			vr.ibytes = vif->bytes_in;
1956 			vr.obytes = vif->bytes_out;
1957 			read_unlock(&mrt_lock);
1958 
1959 			if (copy_to_user(arg, &vr, sizeof(vr)))
1960 				return -EFAULT;
1961 			return 0;
1962 		}
1963 		read_unlock(&mrt_lock);
1964 		return -EADDRNOTAVAIL;
1965 	case SIOCGETSGCNT_IN6:
1966 		if (copy_from_user(&sr, arg, sizeof(sr)))
1967 			return -EFAULT;
1968 
1969 		rcu_read_lock();
1970 		c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
1971 		if (c) {
1972 			sr.pktcnt = c->_c.mfc_un.res.pkt;
1973 			sr.bytecnt = c->_c.mfc_un.res.bytes;
1974 			sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1975 			rcu_read_unlock();
1976 
1977 			if (copy_to_user(arg, &sr, sizeof(sr)))
1978 				return -EFAULT;
1979 			return 0;
1980 		}
1981 		rcu_read_unlock();
1982 		return -EADDRNOTAVAIL;
1983 	default:
1984 		return -ENOIOCTLCMD;
1985 	}
1986 }
1987 #endif
1988 
1989 static inline int ip6mr_forward2_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
1990 {
1991 	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
1992 		      IPSTATS_MIB_OUTFORWDATAGRAMS);
1993 	IP6_ADD_STATS(net, ip6_dst_idev(skb_dst(skb)),
1994 		      IPSTATS_MIB_OUTOCTETS, skb->len);
1995 	return dst_output(net, sk, skb);
1996 }
1997 
1998 /*
1999  *	Processing handlers for ip6mr_forward
2000  */
2001 
2002 static int ip6mr_forward2(struct net *net, struct mr_table *mrt,
2003 			  struct sk_buff *skb, int vifi)
2004 {
2005 	struct ipv6hdr *ipv6h;
2006 	struct vif_device *vif = &mrt->vif_table[vifi];
2007 	struct net_device *dev;
2008 	struct dst_entry *dst;
2009 	struct flowi6 fl6;
2010 
2011 	if (!vif->dev)
2012 		goto out_free;
2013 
2014 #ifdef CONFIG_IPV6_PIMSM_V2
2015 	if (vif->flags & MIFF_REGISTER) {
2016 		vif->pkt_out++;
2017 		vif->bytes_out += skb->len;
2018 		vif->dev->stats.tx_bytes += skb->len;
2019 		vif->dev->stats.tx_packets++;
2020 		ip6mr_cache_report(mrt, skb, vifi, MRT6MSG_WHOLEPKT);
2021 		goto out_free;
2022 	}
2023 #endif
2024 
2025 	ipv6h = ipv6_hdr(skb);
2026 
2027 	fl6 = (struct flowi6) {
2028 		.flowi6_oif = vif->link,
2029 		.daddr = ipv6h->daddr,
2030 	};
2031 
2032 	dst = ip6_route_output(net, NULL, &fl6);
2033 	if (dst->error) {
2034 		dst_release(dst);
2035 		goto out_free;
2036 	}
2037 
2038 	skb_dst_drop(skb);
2039 	skb_dst_set(skb, dst);
2040 
2041 	/*
2042 	 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
2043 	 * not only before forwarding, but after forwarding on all output
2044 	 * interfaces. It is clear, if mrouter runs a multicasting
2045 	 * program, it should receive packets not depending to what interface
2046 	 * program is joined.
2047 	 * If we will not make it, the program will have to join on all
2048 	 * interfaces. On the other hand, multihoming host (or router, but
2049 	 * not mrouter) cannot join to more than one interface - it will
2050 	 * result in receiving multiple packets.
2051 	 */
2052 	dev = vif->dev;
2053 	skb->dev = dev;
2054 	vif->pkt_out++;
2055 	vif->bytes_out += skb->len;
2056 
2057 	/* We are about to write */
2058 	/* XXX: extension headers? */
2059 	if (skb_cow(skb, sizeof(*ipv6h) + LL_RESERVED_SPACE(dev)))
2060 		goto out_free;
2061 
2062 	ipv6h = ipv6_hdr(skb);
2063 	ipv6h->hop_limit--;
2064 
2065 	IP6CB(skb)->flags |= IP6SKB_FORWARDED;
2066 
2067 	return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
2068 		       net, NULL, skb, skb->dev, dev,
2069 		       ip6mr_forward2_finish);
2070 
2071 out_free:
2072 	kfree_skb(skb);
2073 	return 0;
2074 }
2075 
2076 static int ip6mr_find_vif(struct mr_table *mrt, struct net_device *dev)
2077 {
2078 	int ct;
2079 
2080 	for (ct = mrt->maxvif - 1; ct >= 0; ct--) {
2081 		if (mrt->vif_table[ct].dev == dev)
2082 			break;
2083 	}
2084 	return ct;
2085 }
2086 
2087 static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
2088 			   struct net_device *dev, struct sk_buff *skb,
2089 			   struct mfc6_cache *c)
2090 {
2091 	int psend = -1;
2092 	int vif, ct;
2093 	int true_vifi = ip6mr_find_vif(mrt, dev);
2094 
2095 	vif = c->_c.mfc_parent;
2096 	c->_c.mfc_un.res.pkt++;
2097 	c->_c.mfc_un.res.bytes += skb->len;
2098 	c->_c.mfc_un.res.lastuse = jiffies;
2099 
2100 	if (ipv6_addr_any(&c->mf6c_origin) && true_vifi >= 0) {
2101 		struct mfc6_cache *cache_proxy;
2102 
2103 		/* For an (*,G) entry, we only check that the incoming
2104 		 * interface is part of the static tree.
2105 		 */
2106 		rcu_read_lock();
2107 		cache_proxy = mr_mfc_find_any_parent(mrt, vif);
2108 		if (cache_proxy &&
2109 		    cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255) {
2110 			rcu_read_unlock();
2111 			goto forward;
2112 		}
2113 		rcu_read_unlock();
2114 	}
2115 
2116 	/*
2117 	 * Wrong interface: drop packet and (maybe) send PIM assert.
2118 	 */
2119 	if (mrt->vif_table[vif].dev != dev) {
2120 		c->_c.mfc_un.res.wrong_if++;
2121 
2122 		if (true_vifi >= 0 && mrt->mroute_do_assert &&
2123 		    /* pimsm uses asserts, when switching from RPT to SPT,
2124 		       so that we cannot check that packet arrived on an oif.
2125 		       It is bad, but otherwise we would need to move pretty
2126 		       large chunk of pimd to kernel. Ough... --ANK
2127 		     */
2128 		    (mrt->mroute_do_pim ||
2129 		     c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
2130 		    time_after(jiffies,
2131 			       c->_c.mfc_un.res.last_assert +
2132 			       MFC_ASSERT_THRESH)) {
2133 			c->_c.mfc_un.res.last_assert = jiffies;
2134 			ip6mr_cache_report(mrt, skb, true_vifi, MRT6MSG_WRONGMIF);
2135 		}
2136 		goto dont_forward;
2137 	}
2138 
2139 forward:
2140 	mrt->vif_table[vif].pkt_in++;
2141 	mrt->vif_table[vif].bytes_in += skb->len;
2142 
2143 	/*
2144 	 *	Forward the frame
2145 	 */
2146 	if (ipv6_addr_any(&c->mf6c_origin) &&
2147 	    ipv6_addr_any(&c->mf6c_mcastgrp)) {
2148 		if (true_vifi >= 0 &&
2149 		    true_vifi != c->_c.mfc_parent &&
2150 		    ipv6_hdr(skb)->hop_limit >
2151 				c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
2152 			/* It's an (*,*) entry and the packet is not coming from
2153 			 * the upstream: forward the packet to the upstream
2154 			 * only.
2155 			 */
2156 			psend = c->_c.mfc_parent;
2157 			goto last_forward;
2158 		}
2159 		goto dont_forward;
2160 	}
2161 	for (ct = c->_c.mfc_un.res.maxvif - 1;
2162 	     ct >= c->_c.mfc_un.res.minvif; ct--) {
2163 		/* For (*,G) entry, don't forward to the incoming interface */
2164 		if ((!ipv6_addr_any(&c->mf6c_origin) || ct != true_vifi) &&
2165 		    ipv6_hdr(skb)->hop_limit > c->_c.mfc_un.res.ttls[ct]) {
2166 			if (psend != -1) {
2167 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2168 				if (skb2)
2169 					ip6mr_forward2(net, mrt, skb2, psend);
2170 			}
2171 			psend = ct;
2172 		}
2173 	}
2174 last_forward:
2175 	if (psend != -1) {
2176 		ip6mr_forward2(net, mrt, skb, psend);
2177 		return;
2178 	}
2179 
2180 dont_forward:
2181 	kfree_skb(skb);
2182 }
2183 
2184 
2185 /*
2186  *	Multicast packets for forwarding arrive here
2187  */
2188 
2189 int ip6_mr_input(struct sk_buff *skb)
2190 {
2191 	struct mfc6_cache *cache;
2192 	struct net *net = dev_net(skb->dev);
2193 	struct mr_table *mrt;
2194 	struct flowi6 fl6 = {
2195 		.flowi6_iif	= skb->dev->ifindex,
2196 		.flowi6_mark	= skb->mark,
2197 	};
2198 	int err;
2199 	struct net_device *dev;
2200 
2201 	/* skb->dev passed in is the master dev for vrfs.
2202 	 * Get the proper interface that does have a vif associated with it.
2203 	 */
2204 	dev = skb->dev;
2205 	if (netif_is_l3_master(skb->dev)) {
2206 		dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
2207 		if (!dev) {
2208 			kfree_skb(skb);
2209 			return -ENODEV;
2210 		}
2211 	}
2212 
2213 	err = ip6mr_fib_lookup(net, &fl6, &mrt);
2214 	if (err < 0) {
2215 		kfree_skb(skb);
2216 		return err;
2217 	}
2218 
2219 	read_lock(&mrt_lock);
2220 	cache = ip6mr_cache_find(mrt,
2221 				 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr);
2222 	if (!cache) {
2223 		int vif = ip6mr_find_vif(mrt, dev);
2224 
2225 		if (vif >= 0)
2226 			cache = ip6mr_cache_find_any(mrt,
2227 						     &ipv6_hdr(skb)->daddr,
2228 						     vif);
2229 	}
2230 
2231 	/*
2232 	 *	No usable cache entry
2233 	 */
2234 	if (!cache) {
2235 		int vif;
2236 
2237 		vif = ip6mr_find_vif(mrt, dev);
2238 		if (vif >= 0) {
2239 			int err = ip6mr_cache_unresolved(mrt, vif, skb, dev);
2240 			read_unlock(&mrt_lock);
2241 
2242 			return err;
2243 		}
2244 		read_unlock(&mrt_lock);
2245 		kfree_skb(skb);
2246 		return -ENODEV;
2247 	}
2248 
2249 	ip6_mr_forward(net, mrt, dev, skb, cache);
2250 
2251 	read_unlock(&mrt_lock);
2252 
2253 	return 0;
2254 }
2255 
2256 int ip6mr_get_route(struct net *net, struct sk_buff *skb, struct rtmsg *rtm,
2257 		    u32 portid)
2258 {
2259 	int err;
2260 	struct mr_table *mrt;
2261 	struct mfc6_cache *cache;
2262 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
2263 
2264 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
2265 	if (!mrt)
2266 		return -ENOENT;
2267 
2268 	read_lock(&mrt_lock);
2269 	cache = ip6mr_cache_find(mrt, &rt->rt6i_src.addr, &rt->rt6i_dst.addr);
2270 	if (!cache && skb->dev) {
2271 		int vif = ip6mr_find_vif(mrt, skb->dev);
2272 
2273 		if (vif >= 0)
2274 			cache = ip6mr_cache_find_any(mrt, &rt->rt6i_dst.addr,
2275 						     vif);
2276 	}
2277 
2278 	if (!cache) {
2279 		struct sk_buff *skb2;
2280 		struct ipv6hdr *iph;
2281 		struct net_device *dev;
2282 		int vif;
2283 
2284 		dev = skb->dev;
2285 		if (!dev || (vif = ip6mr_find_vif(mrt, dev)) < 0) {
2286 			read_unlock(&mrt_lock);
2287 			return -ENODEV;
2288 		}
2289 
2290 		/* really correct? */
2291 		skb2 = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
2292 		if (!skb2) {
2293 			read_unlock(&mrt_lock);
2294 			return -ENOMEM;
2295 		}
2296 
2297 		NETLINK_CB(skb2).portid = portid;
2298 		skb_reset_transport_header(skb2);
2299 
2300 		skb_put(skb2, sizeof(struct ipv6hdr));
2301 		skb_reset_network_header(skb2);
2302 
2303 		iph = ipv6_hdr(skb2);
2304 		iph->version = 0;
2305 		iph->priority = 0;
2306 		iph->flow_lbl[0] = 0;
2307 		iph->flow_lbl[1] = 0;
2308 		iph->flow_lbl[2] = 0;
2309 		iph->payload_len = 0;
2310 		iph->nexthdr = IPPROTO_NONE;
2311 		iph->hop_limit = 0;
2312 		iph->saddr = rt->rt6i_src.addr;
2313 		iph->daddr = rt->rt6i_dst.addr;
2314 
2315 		err = ip6mr_cache_unresolved(mrt, vif, skb2, dev);
2316 		read_unlock(&mrt_lock);
2317 
2318 		return err;
2319 	}
2320 
2321 	err = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
2322 	read_unlock(&mrt_lock);
2323 	return err;
2324 }
2325 
2326 static int ip6mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2327 			     u32 portid, u32 seq, struct mfc6_cache *c, int cmd,
2328 			     int flags)
2329 {
2330 	struct nlmsghdr *nlh;
2331 	struct rtmsg *rtm;
2332 	int err;
2333 
2334 	nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2335 	if (!nlh)
2336 		return -EMSGSIZE;
2337 
2338 	rtm = nlmsg_data(nlh);
2339 	rtm->rtm_family   = RTNL_FAMILY_IP6MR;
2340 	rtm->rtm_dst_len  = 128;
2341 	rtm->rtm_src_len  = 128;
2342 	rtm->rtm_tos      = 0;
2343 	rtm->rtm_table    = mrt->id;
2344 	if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2345 		goto nla_put_failure;
2346 	rtm->rtm_type = RTN_MULTICAST;
2347 	rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2348 	if (c->_c.mfc_flags & MFC_STATIC)
2349 		rtm->rtm_protocol = RTPROT_STATIC;
2350 	else
2351 		rtm->rtm_protocol = RTPROT_MROUTED;
2352 	rtm->rtm_flags    = 0;
2353 
2354 	if (nla_put_in6_addr(skb, RTA_SRC, &c->mf6c_origin) ||
2355 	    nla_put_in6_addr(skb, RTA_DST, &c->mf6c_mcastgrp))
2356 		goto nla_put_failure;
2357 	err = mr_fill_mroute(mrt, skb, &c->_c, rtm);
2358 	/* do not break the dump if cache is unresolved */
2359 	if (err < 0 && err != -ENOENT)
2360 		goto nla_put_failure;
2361 
2362 	nlmsg_end(skb, nlh);
2363 	return 0;
2364 
2365 nla_put_failure:
2366 	nlmsg_cancel(skb, nlh);
2367 	return -EMSGSIZE;
2368 }
2369 
2370 static int _ip6mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2371 			      u32 portid, u32 seq, struct mr_mfc *c,
2372 			      int cmd, int flags)
2373 {
2374 	return ip6mr_fill_mroute(mrt, skb, portid, seq, (struct mfc6_cache *)c,
2375 				 cmd, flags);
2376 }
2377 
2378 static int mr6_msgsize(bool unresolved, int maxvif)
2379 {
2380 	size_t len =
2381 		NLMSG_ALIGN(sizeof(struct rtmsg))
2382 		+ nla_total_size(4)	/* RTA_TABLE */
2383 		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_SRC */
2384 		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_DST */
2385 		;
2386 
2387 	if (!unresolved)
2388 		len = len
2389 		      + nla_total_size(4)	/* RTA_IIF */
2390 		      + nla_total_size(0)	/* RTA_MULTIPATH */
2391 		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2392 						/* RTA_MFC_STATS */
2393 		      + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
2394 		;
2395 
2396 	return len;
2397 }
2398 
2399 static void mr6_netlink_event(struct mr_table *mrt, struct mfc6_cache *mfc,
2400 			      int cmd)
2401 {
2402 	struct net *net = read_pnet(&mrt->net);
2403 	struct sk_buff *skb;
2404 	int err = -ENOBUFS;
2405 
2406 	skb = nlmsg_new(mr6_msgsize(mfc->_c.mfc_parent >= MAXMIFS, mrt->maxvif),
2407 			GFP_ATOMIC);
2408 	if (!skb)
2409 		goto errout;
2410 
2411 	err = ip6mr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2412 	if (err < 0)
2413 		goto errout;
2414 
2415 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE, NULL, GFP_ATOMIC);
2416 	return;
2417 
2418 errout:
2419 	kfree_skb(skb);
2420 	if (err < 0)
2421 		rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE, err);
2422 }
2423 
2424 static size_t mrt6msg_netlink_msgsize(size_t payloadlen)
2425 {
2426 	size_t len =
2427 		NLMSG_ALIGN(sizeof(struct rtgenmsg))
2428 		+ nla_total_size(1)	/* IP6MRA_CREPORT_MSGTYPE */
2429 		+ nla_total_size(4)	/* IP6MRA_CREPORT_MIF_ID */
2430 					/* IP6MRA_CREPORT_SRC_ADDR */
2431 		+ nla_total_size(sizeof(struct in6_addr))
2432 					/* IP6MRA_CREPORT_DST_ADDR */
2433 		+ nla_total_size(sizeof(struct in6_addr))
2434 					/* IP6MRA_CREPORT_PKT */
2435 		+ nla_total_size(payloadlen)
2436 		;
2437 
2438 	return len;
2439 }
2440 
2441 static void mrt6msg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
2442 {
2443 	struct net *net = read_pnet(&mrt->net);
2444 	struct nlmsghdr *nlh;
2445 	struct rtgenmsg *rtgenm;
2446 	struct mrt6msg *msg;
2447 	struct sk_buff *skb;
2448 	struct nlattr *nla;
2449 	int payloadlen;
2450 
2451 	payloadlen = pkt->len - sizeof(struct mrt6msg);
2452 	msg = (struct mrt6msg *)skb_transport_header(pkt);
2453 
2454 	skb = nlmsg_new(mrt6msg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2455 	if (!skb)
2456 		goto errout;
2457 
2458 	nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
2459 			sizeof(struct rtgenmsg), 0);
2460 	if (!nlh)
2461 		goto errout;
2462 	rtgenm = nlmsg_data(nlh);
2463 	rtgenm->rtgen_family = RTNL_FAMILY_IP6MR;
2464 	if (nla_put_u8(skb, IP6MRA_CREPORT_MSGTYPE, msg->im6_msgtype) ||
2465 	    nla_put_u32(skb, IP6MRA_CREPORT_MIF_ID, msg->im6_mif) ||
2466 	    nla_put_in6_addr(skb, IP6MRA_CREPORT_SRC_ADDR,
2467 			     &msg->im6_src) ||
2468 	    nla_put_in6_addr(skb, IP6MRA_CREPORT_DST_ADDR,
2469 			     &msg->im6_dst))
2470 		goto nla_put_failure;
2471 
2472 	nla = nla_reserve(skb, IP6MRA_CREPORT_PKT, payloadlen);
2473 	if (!nla || skb_copy_bits(pkt, sizeof(struct mrt6msg),
2474 				  nla_data(nla), payloadlen))
2475 		goto nla_put_failure;
2476 
2477 	nlmsg_end(skb, nlh);
2478 
2479 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE_R, NULL, GFP_ATOMIC);
2480 	return;
2481 
2482 nla_put_failure:
2483 	nlmsg_cancel(skb, nlh);
2484 errout:
2485 	kfree_skb(skb);
2486 	rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE_R, -ENOBUFS);
2487 }
2488 
2489 static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2490 {
2491 	const struct nlmsghdr *nlh = cb->nlh;
2492 	struct fib_dump_filter filter = {};
2493 	int err;
2494 
2495 	if (cb->strict_check) {
2496 		err = ip_valid_fib_dump_req(sock_net(skb->sk), nlh,
2497 					    &filter, cb);
2498 		if (err < 0)
2499 			return err;
2500 	}
2501 
2502 	if (filter.table_id) {
2503 		struct mr_table *mrt;
2504 
2505 		mrt = ip6mr_get_table(sock_net(skb->sk), filter.table_id);
2506 		if (!mrt) {
2507 			if (rtnl_msg_family(cb->nlh) != RTNL_FAMILY_IP6MR)
2508 				return skb->len;
2509 
2510 			NL_SET_ERR_MSG_MOD(cb->extack, "MR table does not exist");
2511 			return -ENOENT;
2512 		}
2513 		err = mr_table_dump(mrt, skb, cb, _ip6mr_fill_mroute,
2514 				    &mfc_unres_lock, &filter);
2515 		return skb->len ? : err;
2516 	}
2517 
2518 	return mr_rtm_dumproute(skb, cb, ip6mr_mr_table_iter,
2519 				_ip6mr_fill_mroute, &mfc_unres_lock, &filter);
2520 }
2521