xref: /linux/net/ipv6/ip6mr.c (revision 6ebe6dbd6886af07b102aca42e44edbee94a22d9)
1 /*
2  *	Linux IPv6 multicast routing support for BSD pim6sd
3  *	Based on net/ipv4/ipmr.c.
4  *
5  *	(c) 2004 Mickael Hoerdt, <hoerdt@clarinet.u-strasbg.fr>
6  *		LSIIT Laboratory, Strasbourg, France
7  *	(c) 2004 Jean-Philippe Andriot, <jean-philippe.andriot@6WIND.com>
8  *		6WIND, Paris, France
9  *	Copyright (C)2007,2008 USAGI/WIDE Project
10  *		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
11  *
12  *	This program is free software; you can redistribute it and/or
13  *	modify it under the terms of the GNU General Public License
14  *	as published by the Free Software Foundation; either version
15  *	2 of the License, or (at your option) any later version.
16  *
17  */
18 
19 #include <linux/uaccess.h>
20 #include <linux/types.h>
21 #include <linux/sched.h>
22 #include <linux/errno.h>
23 #include <linux/timer.h>
24 #include <linux/mm.h>
25 #include <linux/kernel.h>
26 #include <linux/fcntl.h>
27 #include <linux/stat.h>
28 #include <linux/socket.h>
29 #include <linux/inet.h>
30 #include <linux/netdevice.h>
31 #include <linux/inetdevice.h>
32 #include <linux/proc_fs.h>
33 #include <linux/seq_file.h>
34 #include <linux/init.h>
35 #include <linux/slab.h>
36 #include <linux/compat.h>
37 #include <net/protocol.h>
38 #include <linux/skbuff.h>
39 #include <net/sock.h>
40 #include <net/raw.h>
41 #include <linux/notifier.h>
42 #include <linux/if_arp.h>
43 #include <net/checksum.h>
44 #include <net/netlink.h>
45 #include <net/fib_rules.h>
46 
47 #include <net/ipv6.h>
48 #include <net/ip6_route.h>
49 #include <linux/mroute6.h>
50 #include <linux/pim.h>
51 #include <net/addrconf.h>
52 #include <linux/netfilter_ipv6.h>
53 #include <linux/export.h>
54 #include <net/ip6_checksum.h>
55 #include <linux/netconf.h>
56 
57 struct mr6_table {
58 	struct list_head	list;
59 	possible_net_t		net;
60 	u32			id;
61 	struct sock		*mroute6_sk;
62 	struct timer_list	ipmr_expire_timer;
63 	struct list_head	mfc6_unres_queue;
64 	struct list_head	mfc6_cache_array[MFC6_LINES];
65 	struct mif_device	vif6_table[MAXMIFS];
66 	int			maxvif;
67 	atomic_t		cache_resolve_queue_len;
68 	bool			mroute_do_assert;
69 	bool			mroute_do_pim;
70 #ifdef CONFIG_IPV6_PIMSM_V2
71 	int			mroute_reg_vif_num;
72 #endif
73 };
74 
75 struct ip6mr_rule {
76 	struct fib_rule		common;
77 };
78 
79 struct ip6mr_result {
80 	struct mr6_table	*mrt;
81 };
82 
83 /* Big lock, protecting vif table, mrt cache and mroute socket state.
84    Note that the changes are semaphored via rtnl_lock.
85  */
86 
87 static DEFINE_RWLOCK(mrt_lock);
88 
89 /*
90  *	Multicast router control variables
91  */
92 
93 #define MIF_EXISTS(_mrt, _idx) ((_mrt)->vif6_table[_idx].dev != NULL)
94 
95 /* Special spinlock for queue of unresolved entries */
96 static DEFINE_SPINLOCK(mfc_unres_lock);
97 
98 /* We return to original Alan's scheme. Hash table of resolved
99    entries is changed only in process context and protected
100    with weak lock mrt_lock. Queue of unresolved entries is protected
101    with strong spinlock mfc_unres_lock.
102 
103    In this case data path is free of exclusive locks at all.
104  */
105 
106 static struct kmem_cache *mrt_cachep __read_mostly;
107 
108 static struct mr6_table *ip6mr_new_table(struct net *net, u32 id);
109 static void ip6mr_free_table(struct mr6_table *mrt);
110 
111 static void ip6_mr_forward(struct net *net, struct mr6_table *mrt,
112 			   struct sk_buff *skb, struct mfc6_cache *cache);
113 static int ip6mr_cache_report(struct mr6_table *mrt, struct sk_buff *pkt,
114 			      mifi_t mifi, int assert);
115 static int __ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
116 			       struct mfc6_cache *c, struct rtmsg *rtm);
117 static void mr6_netlink_event(struct mr6_table *mrt, struct mfc6_cache *mfc,
118 			      int cmd);
119 static void mrt6msg_netlink_event(struct mr6_table *mrt, struct sk_buff *pkt);
120 static int ip6mr_rtm_dumproute(struct sk_buff *skb,
121 			       struct netlink_callback *cb);
122 static void mroute_clean_tables(struct mr6_table *mrt, bool all);
123 static void ipmr_expire_process(struct timer_list *t);
124 
125 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
126 #define ip6mr_for_each_table(mrt, net) \
127 	list_for_each_entry_rcu(mrt, &net->ipv6.mr6_tables, list)
128 
129 static struct mr6_table *ip6mr_get_table(struct net *net, u32 id)
130 {
131 	struct mr6_table *mrt;
132 
133 	ip6mr_for_each_table(mrt, net) {
134 		if (mrt->id == id)
135 			return mrt;
136 	}
137 	return NULL;
138 }
139 
140 static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
141 			    struct mr6_table **mrt)
142 {
143 	int err;
144 	struct ip6mr_result res;
145 	struct fib_lookup_arg arg = {
146 		.result = &res,
147 		.flags = FIB_LOOKUP_NOREF,
148 	};
149 
150 	err = fib_rules_lookup(net->ipv6.mr6_rules_ops,
151 			       flowi6_to_flowi(flp6), 0, &arg);
152 	if (err < 0)
153 		return err;
154 	*mrt = res.mrt;
155 	return 0;
156 }
157 
158 static int ip6mr_rule_action(struct fib_rule *rule, struct flowi *flp,
159 			     int flags, struct fib_lookup_arg *arg)
160 {
161 	struct ip6mr_result *res = arg->result;
162 	struct mr6_table *mrt;
163 
164 	switch (rule->action) {
165 	case FR_ACT_TO_TBL:
166 		break;
167 	case FR_ACT_UNREACHABLE:
168 		return -ENETUNREACH;
169 	case FR_ACT_PROHIBIT:
170 		return -EACCES;
171 	case FR_ACT_BLACKHOLE:
172 	default:
173 		return -EINVAL;
174 	}
175 
176 	mrt = ip6mr_get_table(rule->fr_net, rule->table);
177 	if (!mrt)
178 		return -EAGAIN;
179 	res->mrt = mrt;
180 	return 0;
181 }
182 
183 static int ip6mr_rule_match(struct fib_rule *rule, struct flowi *flp, int flags)
184 {
185 	return 1;
186 }
187 
188 static const struct nla_policy ip6mr_rule_policy[FRA_MAX + 1] = {
189 	FRA_GENERIC_POLICY,
190 };
191 
192 static int ip6mr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
193 				struct fib_rule_hdr *frh, struct nlattr **tb)
194 {
195 	return 0;
196 }
197 
198 static int ip6mr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
199 			      struct nlattr **tb)
200 {
201 	return 1;
202 }
203 
204 static int ip6mr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
205 			   struct fib_rule_hdr *frh)
206 {
207 	frh->dst_len = 0;
208 	frh->src_len = 0;
209 	frh->tos     = 0;
210 	return 0;
211 }
212 
213 static const struct fib_rules_ops __net_initconst ip6mr_rules_ops_template = {
214 	.family		= RTNL_FAMILY_IP6MR,
215 	.rule_size	= sizeof(struct ip6mr_rule),
216 	.addr_size	= sizeof(struct in6_addr),
217 	.action		= ip6mr_rule_action,
218 	.match		= ip6mr_rule_match,
219 	.configure	= ip6mr_rule_configure,
220 	.compare	= ip6mr_rule_compare,
221 	.fill		= ip6mr_rule_fill,
222 	.nlgroup	= RTNLGRP_IPV6_RULE,
223 	.policy		= ip6mr_rule_policy,
224 	.owner		= THIS_MODULE,
225 };
226 
227 static int __net_init ip6mr_rules_init(struct net *net)
228 {
229 	struct fib_rules_ops *ops;
230 	struct mr6_table *mrt;
231 	int err;
232 
233 	ops = fib_rules_register(&ip6mr_rules_ops_template, net);
234 	if (IS_ERR(ops))
235 		return PTR_ERR(ops);
236 
237 	INIT_LIST_HEAD(&net->ipv6.mr6_tables);
238 
239 	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
240 	if (!mrt) {
241 		err = -ENOMEM;
242 		goto err1;
243 	}
244 
245 	err = fib_default_rule_add(ops, 0x7fff, RT6_TABLE_DFLT, 0);
246 	if (err < 0)
247 		goto err2;
248 
249 	net->ipv6.mr6_rules_ops = ops;
250 	return 0;
251 
252 err2:
253 	ip6mr_free_table(mrt);
254 err1:
255 	fib_rules_unregister(ops);
256 	return err;
257 }
258 
259 static void __net_exit ip6mr_rules_exit(struct net *net)
260 {
261 	struct mr6_table *mrt, *next;
262 
263 	rtnl_lock();
264 	list_for_each_entry_safe(mrt, next, &net->ipv6.mr6_tables, list) {
265 		list_del(&mrt->list);
266 		ip6mr_free_table(mrt);
267 	}
268 	fib_rules_unregister(net->ipv6.mr6_rules_ops);
269 	rtnl_unlock();
270 }
271 #else
272 #define ip6mr_for_each_table(mrt, net) \
273 	for (mrt = net->ipv6.mrt6; mrt; mrt = NULL)
274 
275 static struct mr6_table *ip6mr_get_table(struct net *net, u32 id)
276 {
277 	return net->ipv6.mrt6;
278 }
279 
280 static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
281 			    struct mr6_table **mrt)
282 {
283 	*mrt = net->ipv6.mrt6;
284 	return 0;
285 }
286 
287 static int __net_init ip6mr_rules_init(struct net *net)
288 {
289 	net->ipv6.mrt6 = ip6mr_new_table(net, RT6_TABLE_DFLT);
290 	return net->ipv6.mrt6 ? 0 : -ENOMEM;
291 }
292 
293 static void __net_exit ip6mr_rules_exit(struct net *net)
294 {
295 	rtnl_lock();
296 	ip6mr_free_table(net->ipv6.mrt6);
297 	net->ipv6.mrt6 = NULL;
298 	rtnl_unlock();
299 }
300 #endif
301 
302 static struct mr6_table *ip6mr_new_table(struct net *net, u32 id)
303 {
304 	struct mr6_table *mrt;
305 	unsigned int i;
306 
307 	mrt = ip6mr_get_table(net, id);
308 	if (mrt)
309 		return mrt;
310 
311 	mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
312 	if (!mrt)
313 		return NULL;
314 	mrt->id = id;
315 	write_pnet(&mrt->net, net);
316 
317 	/* Forwarding cache */
318 	for (i = 0; i < MFC6_LINES; i++)
319 		INIT_LIST_HEAD(&mrt->mfc6_cache_array[i]);
320 
321 	INIT_LIST_HEAD(&mrt->mfc6_unres_queue);
322 
323 	timer_setup(&mrt->ipmr_expire_timer, ipmr_expire_process, 0);
324 
325 #ifdef CONFIG_IPV6_PIMSM_V2
326 	mrt->mroute_reg_vif_num = -1;
327 #endif
328 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
329 	list_add_tail_rcu(&mrt->list, &net->ipv6.mr6_tables);
330 #endif
331 	return mrt;
332 }
333 
334 static void ip6mr_free_table(struct mr6_table *mrt)
335 {
336 	del_timer_sync(&mrt->ipmr_expire_timer);
337 	mroute_clean_tables(mrt, true);
338 	kfree(mrt);
339 }
340 
341 #ifdef CONFIG_PROC_FS
342 
343 struct ipmr_mfc_iter {
344 	struct seq_net_private p;
345 	struct mr6_table *mrt;
346 	struct list_head *cache;
347 	int ct;
348 };
349 
350 
351 static struct mfc6_cache *ipmr_mfc_seq_idx(struct net *net,
352 					   struct ipmr_mfc_iter *it, loff_t pos)
353 {
354 	struct mr6_table *mrt = it->mrt;
355 	struct mfc6_cache *mfc;
356 
357 	read_lock(&mrt_lock);
358 	for (it->ct = 0; it->ct < MFC6_LINES; it->ct++) {
359 		it->cache = &mrt->mfc6_cache_array[it->ct];
360 		list_for_each_entry(mfc, it->cache, list)
361 			if (pos-- == 0)
362 				return mfc;
363 	}
364 	read_unlock(&mrt_lock);
365 
366 	spin_lock_bh(&mfc_unres_lock);
367 	it->cache = &mrt->mfc6_unres_queue;
368 	list_for_each_entry(mfc, it->cache, list)
369 		if (pos-- == 0)
370 			return mfc;
371 	spin_unlock_bh(&mfc_unres_lock);
372 
373 	it->cache = NULL;
374 	return NULL;
375 }
376 
377 /*
378  *	The /proc interfaces to multicast routing /proc/ip6_mr_cache /proc/ip6_mr_vif
379  */
380 
381 struct ipmr_vif_iter {
382 	struct seq_net_private p;
383 	struct mr6_table *mrt;
384 	int ct;
385 };
386 
387 static struct mif_device *ip6mr_vif_seq_idx(struct net *net,
388 					    struct ipmr_vif_iter *iter,
389 					    loff_t pos)
390 {
391 	struct mr6_table *mrt = iter->mrt;
392 
393 	for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
394 		if (!MIF_EXISTS(mrt, iter->ct))
395 			continue;
396 		if (pos-- == 0)
397 			return &mrt->vif6_table[iter->ct];
398 	}
399 	return NULL;
400 }
401 
402 static void *ip6mr_vif_seq_start(struct seq_file *seq, loff_t *pos)
403 	__acquires(mrt_lock)
404 {
405 	struct ipmr_vif_iter *iter = seq->private;
406 	struct net *net = seq_file_net(seq);
407 	struct mr6_table *mrt;
408 
409 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
410 	if (!mrt)
411 		return ERR_PTR(-ENOENT);
412 
413 	iter->mrt = mrt;
414 
415 	read_lock(&mrt_lock);
416 	return *pos ? ip6mr_vif_seq_idx(net, seq->private, *pos - 1)
417 		: SEQ_START_TOKEN;
418 }
419 
420 static void *ip6mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
421 {
422 	struct ipmr_vif_iter *iter = seq->private;
423 	struct net *net = seq_file_net(seq);
424 	struct mr6_table *mrt = iter->mrt;
425 
426 	++*pos;
427 	if (v == SEQ_START_TOKEN)
428 		return ip6mr_vif_seq_idx(net, iter, 0);
429 
430 	while (++iter->ct < mrt->maxvif) {
431 		if (!MIF_EXISTS(mrt, iter->ct))
432 			continue;
433 		return &mrt->vif6_table[iter->ct];
434 	}
435 	return NULL;
436 }
437 
438 static void ip6mr_vif_seq_stop(struct seq_file *seq, void *v)
439 	__releases(mrt_lock)
440 {
441 	read_unlock(&mrt_lock);
442 }
443 
444 static int ip6mr_vif_seq_show(struct seq_file *seq, void *v)
445 {
446 	struct ipmr_vif_iter *iter = seq->private;
447 	struct mr6_table *mrt = iter->mrt;
448 
449 	if (v == SEQ_START_TOKEN) {
450 		seq_puts(seq,
451 			 "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags\n");
452 	} else {
453 		const struct mif_device *vif = v;
454 		const char *name = vif->dev ? vif->dev->name : "none";
455 
456 		seq_printf(seq,
457 			   "%2td %-10s %8ld %7ld  %8ld %7ld %05X\n",
458 			   vif - mrt->vif6_table,
459 			   name, vif->bytes_in, vif->pkt_in,
460 			   vif->bytes_out, vif->pkt_out,
461 			   vif->flags);
462 	}
463 	return 0;
464 }
465 
466 static const struct seq_operations ip6mr_vif_seq_ops = {
467 	.start = ip6mr_vif_seq_start,
468 	.next  = ip6mr_vif_seq_next,
469 	.stop  = ip6mr_vif_seq_stop,
470 	.show  = ip6mr_vif_seq_show,
471 };
472 
473 static int ip6mr_vif_open(struct inode *inode, struct file *file)
474 {
475 	return seq_open_net(inode, file, &ip6mr_vif_seq_ops,
476 			    sizeof(struct ipmr_vif_iter));
477 }
478 
479 static const struct file_operations ip6mr_vif_fops = {
480 	.owner	 = THIS_MODULE,
481 	.open    = ip6mr_vif_open,
482 	.read    = seq_read,
483 	.llseek  = seq_lseek,
484 	.release = seq_release_net,
485 };
486 
487 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
488 {
489 	struct ipmr_mfc_iter *it = seq->private;
490 	struct net *net = seq_file_net(seq);
491 	struct mr6_table *mrt;
492 
493 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
494 	if (!mrt)
495 		return ERR_PTR(-ENOENT);
496 
497 	it->mrt = mrt;
498 	return *pos ? ipmr_mfc_seq_idx(net, seq->private, *pos - 1)
499 		: SEQ_START_TOKEN;
500 }
501 
502 static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
503 {
504 	struct mfc6_cache *mfc = v;
505 	struct ipmr_mfc_iter *it = seq->private;
506 	struct net *net = seq_file_net(seq);
507 	struct mr6_table *mrt = it->mrt;
508 
509 	++*pos;
510 
511 	if (v == SEQ_START_TOKEN)
512 		return ipmr_mfc_seq_idx(net, seq->private, 0);
513 
514 	if (mfc->list.next != it->cache)
515 		return list_entry(mfc->list.next, struct mfc6_cache, list);
516 
517 	if (it->cache == &mrt->mfc6_unres_queue)
518 		goto end_of_list;
519 
520 	BUG_ON(it->cache != &mrt->mfc6_cache_array[it->ct]);
521 
522 	while (++it->ct < MFC6_LINES) {
523 		it->cache = &mrt->mfc6_cache_array[it->ct];
524 		if (list_empty(it->cache))
525 			continue;
526 		return list_first_entry(it->cache, struct mfc6_cache, list);
527 	}
528 
529 	/* exhausted cache_array, show unresolved */
530 	read_unlock(&mrt_lock);
531 	it->cache = &mrt->mfc6_unres_queue;
532 	it->ct = 0;
533 
534 	spin_lock_bh(&mfc_unres_lock);
535 	if (!list_empty(it->cache))
536 		return list_first_entry(it->cache, struct mfc6_cache, list);
537 
538  end_of_list:
539 	spin_unlock_bh(&mfc_unres_lock);
540 	it->cache = NULL;
541 
542 	return NULL;
543 }
544 
545 static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
546 {
547 	struct ipmr_mfc_iter *it = seq->private;
548 	struct mr6_table *mrt = it->mrt;
549 
550 	if (it->cache == &mrt->mfc6_unres_queue)
551 		spin_unlock_bh(&mfc_unres_lock);
552 	else if (it->cache == &mrt->mfc6_cache_array[it->ct])
553 		read_unlock(&mrt_lock);
554 }
555 
556 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
557 {
558 	int n;
559 
560 	if (v == SEQ_START_TOKEN) {
561 		seq_puts(seq,
562 			 "Group                            "
563 			 "Origin                           "
564 			 "Iif      Pkts  Bytes     Wrong  Oifs\n");
565 	} else {
566 		const struct mfc6_cache *mfc = v;
567 		const struct ipmr_mfc_iter *it = seq->private;
568 		struct mr6_table *mrt = it->mrt;
569 
570 		seq_printf(seq, "%pI6 %pI6 %-3hd",
571 			   &mfc->mf6c_mcastgrp, &mfc->mf6c_origin,
572 			   mfc->mf6c_parent);
573 
574 		if (it->cache != &mrt->mfc6_unres_queue) {
575 			seq_printf(seq, " %8lu %8lu %8lu",
576 				   mfc->mfc_un.res.pkt,
577 				   mfc->mfc_un.res.bytes,
578 				   mfc->mfc_un.res.wrong_if);
579 			for (n = mfc->mfc_un.res.minvif;
580 			     n < mfc->mfc_un.res.maxvif; n++) {
581 				if (MIF_EXISTS(mrt, n) &&
582 				    mfc->mfc_un.res.ttls[n] < 255)
583 					seq_printf(seq,
584 						   " %2d:%-3d",
585 						   n, mfc->mfc_un.res.ttls[n]);
586 			}
587 		} else {
588 			/* unresolved mfc_caches don't contain
589 			 * pkt, bytes and wrong_if values
590 			 */
591 			seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
592 		}
593 		seq_putc(seq, '\n');
594 	}
595 	return 0;
596 }
597 
598 static const struct seq_operations ipmr_mfc_seq_ops = {
599 	.start = ipmr_mfc_seq_start,
600 	.next  = ipmr_mfc_seq_next,
601 	.stop  = ipmr_mfc_seq_stop,
602 	.show  = ipmr_mfc_seq_show,
603 };
604 
605 static int ipmr_mfc_open(struct inode *inode, struct file *file)
606 {
607 	return seq_open_net(inode, file, &ipmr_mfc_seq_ops,
608 			    sizeof(struct ipmr_mfc_iter));
609 }
610 
611 static const struct file_operations ip6mr_mfc_fops = {
612 	.owner	 = THIS_MODULE,
613 	.open    = ipmr_mfc_open,
614 	.read    = seq_read,
615 	.llseek  = seq_lseek,
616 	.release = seq_release_net,
617 };
618 #endif
619 
620 #ifdef CONFIG_IPV6_PIMSM_V2
621 
622 static int pim6_rcv(struct sk_buff *skb)
623 {
624 	struct pimreghdr *pim;
625 	struct ipv6hdr   *encap;
626 	struct net_device  *reg_dev = NULL;
627 	struct net *net = dev_net(skb->dev);
628 	struct mr6_table *mrt;
629 	struct flowi6 fl6 = {
630 		.flowi6_iif	= skb->dev->ifindex,
631 		.flowi6_mark	= skb->mark,
632 	};
633 	int reg_vif_num;
634 
635 	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
636 		goto drop;
637 
638 	pim = (struct pimreghdr *)skb_transport_header(skb);
639 	if (pim->type != ((PIM_VERSION << 4) | PIM_TYPE_REGISTER) ||
640 	    (pim->flags & PIM_NULL_REGISTER) ||
641 	    (csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
642 			     sizeof(*pim), IPPROTO_PIM,
643 			     csum_partial((void *)pim, sizeof(*pim), 0)) &&
644 	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
645 		goto drop;
646 
647 	/* check if the inner packet is destined to mcast group */
648 	encap = (struct ipv6hdr *)(skb_transport_header(skb) +
649 				   sizeof(*pim));
650 
651 	if (!ipv6_addr_is_multicast(&encap->daddr) ||
652 	    encap->payload_len == 0 ||
653 	    ntohs(encap->payload_len) + sizeof(*pim) > skb->len)
654 		goto drop;
655 
656 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
657 		goto drop;
658 	reg_vif_num = mrt->mroute_reg_vif_num;
659 
660 	read_lock(&mrt_lock);
661 	if (reg_vif_num >= 0)
662 		reg_dev = mrt->vif6_table[reg_vif_num].dev;
663 	if (reg_dev)
664 		dev_hold(reg_dev);
665 	read_unlock(&mrt_lock);
666 
667 	if (!reg_dev)
668 		goto drop;
669 
670 	skb->mac_header = skb->network_header;
671 	skb_pull(skb, (u8 *)encap - skb->data);
672 	skb_reset_network_header(skb);
673 	skb->protocol = htons(ETH_P_IPV6);
674 	skb->ip_summed = CHECKSUM_NONE;
675 
676 	skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
677 
678 	netif_rx(skb);
679 
680 	dev_put(reg_dev);
681 	return 0;
682  drop:
683 	kfree_skb(skb);
684 	return 0;
685 }
686 
687 static const struct inet6_protocol pim6_protocol = {
688 	.handler	=	pim6_rcv,
689 };
690 
691 /* Service routines creating virtual interfaces: PIMREG */
692 
693 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb,
694 				      struct net_device *dev)
695 {
696 	struct net *net = dev_net(dev);
697 	struct mr6_table *mrt;
698 	struct flowi6 fl6 = {
699 		.flowi6_oif	= dev->ifindex,
700 		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
701 		.flowi6_mark	= skb->mark,
702 	};
703 	int err;
704 
705 	err = ip6mr_fib_lookup(net, &fl6, &mrt);
706 	if (err < 0) {
707 		kfree_skb(skb);
708 		return err;
709 	}
710 
711 	read_lock(&mrt_lock);
712 	dev->stats.tx_bytes += skb->len;
713 	dev->stats.tx_packets++;
714 	ip6mr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, MRT6MSG_WHOLEPKT);
715 	read_unlock(&mrt_lock);
716 	kfree_skb(skb);
717 	return NETDEV_TX_OK;
718 }
719 
720 static int reg_vif_get_iflink(const struct net_device *dev)
721 {
722 	return 0;
723 }
724 
725 static const struct net_device_ops reg_vif_netdev_ops = {
726 	.ndo_start_xmit	= reg_vif_xmit,
727 	.ndo_get_iflink = reg_vif_get_iflink,
728 };
729 
730 static void reg_vif_setup(struct net_device *dev)
731 {
732 	dev->type		= ARPHRD_PIMREG;
733 	dev->mtu		= 1500 - sizeof(struct ipv6hdr) - 8;
734 	dev->flags		= IFF_NOARP;
735 	dev->netdev_ops		= &reg_vif_netdev_ops;
736 	dev->needs_free_netdev	= true;
737 	dev->features		|= NETIF_F_NETNS_LOCAL;
738 }
739 
740 static struct net_device *ip6mr_reg_vif(struct net *net, struct mr6_table *mrt)
741 {
742 	struct net_device *dev;
743 	char name[IFNAMSIZ];
744 
745 	if (mrt->id == RT6_TABLE_DFLT)
746 		sprintf(name, "pim6reg");
747 	else
748 		sprintf(name, "pim6reg%u", mrt->id);
749 
750 	dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
751 	if (!dev)
752 		return NULL;
753 
754 	dev_net_set(dev, net);
755 
756 	if (register_netdevice(dev)) {
757 		free_netdev(dev);
758 		return NULL;
759 	}
760 
761 	if (dev_open(dev))
762 		goto failure;
763 
764 	dev_hold(dev);
765 	return dev;
766 
767 failure:
768 	unregister_netdevice(dev);
769 	return NULL;
770 }
771 #endif
772 
773 /*
774  *	Delete a VIF entry
775  */
776 
777 static int mif6_delete(struct mr6_table *mrt, int vifi, int notify,
778 		       struct list_head *head)
779 {
780 	struct mif_device *v;
781 	struct net_device *dev;
782 	struct inet6_dev *in6_dev;
783 
784 	if (vifi < 0 || vifi >= mrt->maxvif)
785 		return -EADDRNOTAVAIL;
786 
787 	v = &mrt->vif6_table[vifi];
788 
789 	write_lock_bh(&mrt_lock);
790 	dev = v->dev;
791 	v->dev = NULL;
792 
793 	if (!dev) {
794 		write_unlock_bh(&mrt_lock);
795 		return -EADDRNOTAVAIL;
796 	}
797 
798 #ifdef CONFIG_IPV6_PIMSM_V2
799 	if (vifi == mrt->mroute_reg_vif_num)
800 		mrt->mroute_reg_vif_num = -1;
801 #endif
802 
803 	if (vifi + 1 == mrt->maxvif) {
804 		int tmp;
805 		for (tmp = vifi - 1; tmp >= 0; tmp--) {
806 			if (MIF_EXISTS(mrt, tmp))
807 				break;
808 		}
809 		mrt->maxvif = tmp + 1;
810 	}
811 
812 	write_unlock_bh(&mrt_lock);
813 
814 	dev_set_allmulti(dev, -1);
815 
816 	in6_dev = __in6_dev_get(dev);
817 	if (in6_dev) {
818 		in6_dev->cnf.mc_forwarding--;
819 		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
820 					     NETCONFA_MC_FORWARDING,
821 					     dev->ifindex, &in6_dev->cnf);
822 	}
823 
824 	if ((v->flags & MIFF_REGISTER) && !notify)
825 		unregister_netdevice_queue(dev, head);
826 
827 	dev_put(dev);
828 	return 0;
829 }
830 
831 static inline void ip6mr_cache_free(struct mfc6_cache *c)
832 {
833 	kmem_cache_free(mrt_cachep, c);
834 }
835 
836 /* Destroy an unresolved cache entry, killing queued skbs
837    and reporting error to netlink readers.
838  */
839 
840 static void ip6mr_destroy_unres(struct mr6_table *mrt, struct mfc6_cache *c)
841 {
842 	struct net *net = read_pnet(&mrt->net);
843 	struct sk_buff *skb;
844 
845 	atomic_dec(&mrt->cache_resolve_queue_len);
846 
847 	while ((skb = skb_dequeue(&c->mfc_un.unres.unresolved)) != NULL) {
848 		if (ipv6_hdr(skb)->version == 0) {
849 			struct nlmsghdr *nlh = skb_pull(skb,
850 							sizeof(struct ipv6hdr));
851 			nlh->nlmsg_type = NLMSG_ERROR;
852 			nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
853 			skb_trim(skb, nlh->nlmsg_len);
854 			((struct nlmsgerr *)nlmsg_data(nlh))->error = -ETIMEDOUT;
855 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
856 		} else
857 			kfree_skb(skb);
858 	}
859 
860 	ip6mr_cache_free(c);
861 }
862 
863 
864 /* Timer process for all the unresolved queue. */
865 
866 static void ipmr_do_expire_process(struct mr6_table *mrt)
867 {
868 	unsigned long now = jiffies;
869 	unsigned long expires = 10 * HZ;
870 	struct mfc6_cache *c, *next;
871 
872 	list_for_each_entry_safe(c, next, &mrt->mfc6_unres_queue, list) {
873 		if (time_after(c->mfc_un.unres.expires, now)) {
874 			/* not yet... */
875 			unsigned long interval = c->mfc_un.unres.expires - now;
876 			if (interval < expires)
877 				expires = interval;
878 			continue;
879 		}
880 
881 		list_del(&c->list);
882 		mr6_netlink_event(mrt, c, RTM_DELROUTE);
883 		ip6mr_destroy_unres(mrt, c);
884 	}
885 
886 	if (!list_empty(&mrt->mfc6_unres_queue))
887 		mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
888 }
889 
890 static void ipmr_expire_process(struct timer_list *t)
891 {
892 	struct mr6_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
893 
894 	if (!spin_trylock(&mfc_unres_lock)) {
895 		mod_timer(&mrt->ipmr_expire_timer, jiffies + 1);
896 		return;
897 	}
898 
899 	if (!list_empty(&mrt->mfc6_unres_queue))
900 		ipmr_do_expire_process(mrt);
901 
902 	spin_unlock(&mfc_unres_lock);
903 }
904 
905 /* Fill oifs list. It is called under write locked mrt_lock. */
906 
907 static void ip6mr_update_thresholds(struct mr6_table *mrt, struct mfc6_cache *cache,
908 				    unsigned char *ttls)
909 {
910 	int vifi;
911 
912 	cache->mfc_un.res.minvif = MAXMIFS;
913 	cache->mfc_un.res.maxvif = 0;
914 	memset(cache->mfc_un.res.ttls, 255, MAXMIFS);
915 
916 	for (vifi = 0; vifi < mrt->maxvif; vifi++) {
917 		if (MIF_EXISTS(mrt, vifi) &&
918 		    ttls[vifi] && ttls[vifi] < 255) {
919 			cache->mfc_un.res.ttls[vifi] = ttls[vifi];
920 			if (cache->mfc_un.res.minvif > vifi)
921 				cache->mfc_un.res.minvif = vifi;
922 			if (cache->mfc_un.res.maxvif <= vifi)
923 				cache->mfc_un.res.maxvif = vifi + 1;
924 		}
925 	}
926 	cache->mfc_un.res.lastuse = jiffies;
927 }
928 
929 static int mif6_add(struct net *net, struct mr6_table *mrt,
930 		    struct mif6ctl *vifc, int mrtsock)
931 {
932 	int vifi = vifc->mif6c_mifi;
933 	struct mif_device *v = &mrt->vif6_table[vifi];
934 	struct net_device *dev;
935 	struct inet6_dev *in6_dev;
936 	int err;
937 
938 	/* Is vif busy ? */
939 	if (MIF_EXISTS(mrt, vifi))
940 		return -EADDRINUSE;
941 
942 	switch (vifc->mif6c_flags) {
943 #ifdef CONFIG_IPV6_PIMSM_V2
944 	case MIFF_REGISTER:
945 		/*
946 		 * Special Purpose VIF in PIM
947 		 * All the packets will be sent to the daemon
948 		 */
949 		if (mrt->mroute_reg_vif_num >= 0)
950 			return -EADDRINUSE;
951 		dev = ip6mr_reg_vif(net, mrt);
952 		if (!dev)
953 			return -ENOBUFS;
954 		err = dev_set_allmulti(dev, 1);
955 		if (err) {
956 			unregister_netdevice(dev);
957 			dev_put(dev);
958 			return err;
959 		}
960 		break;
961 #endif
962 	case 0:
963 		dev = dev_get_by_index(net, vifc->mif6c_pifi);
964 		if (!dev)
965 			return -EADDRNOTAVAIL;
966 		err = dev_set_allmulti(dev, 1);
967 		if (err) {
968 			dev_put(dev);
969 			return err;
970 		}
971 		break;
972 	default:
973 		return -EINVAL;
974 	}
975 
976 	in6_dev = __in6_dev_get(dev);
977 	if (in6_dev) {
978 		in6_dev->cnf.mc_forwarding++;
979 		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
980 					     NETCONFA_MC_FORWARDING,
981 					     dev->ifindex, &in6_dev->cnf);
982 	}
983 
984 	/*
985 	 *	Fill in the VIF structures
986 	 */
987 	v->rate_limit = vifc->vifc_rate_limit;
988 	v->flags = vifc->mif6c_flags;
989 	if (!mrtsock)
990 		v->flags |= VIFF_STATIC;
991 	v->threshold = vifc->vifc_threshold;
992 	v->bytes_in = 0;
993 	v->bytes_out = 0;
994 	v->pkt_in = 0;
995 	v->pkt_out = 0;
996 	v->link = dev->ifindex;
997 	if (v->flags & MIFF_REGISTER)
998 		v->link = dev_get_iflink(dev);
999 
1000 	/* And finish update writing critical data */
1001 	write_lock_bh(&mrt_lock);
1002 	v->dev = dev;
1003 #ifdef CONFIG_IPV6_PIMSM_V2
1004 	if (v->flags & MIFF_REGISTER)
1005 		mrt->mroute_reg_vif_num = vifi;
1006 #endif
1007 	if (vifi + 1 > mrt->maxvif)
1008 		mrt->maxvif = vifi + 1;
1009 	write_unlock_bh(&mrt_lock);
1010 	return 0;
1011 }
1012 
1013 static struct mfc6_cache *ip6mr_cache_find(struct mr6_table *mrt,
1014 					   const struct in6_addr *origin,
1015 					   const struct in6_addr *mcastgrp)
1016 {
1017 	int line = MFC6_HASH(mcastgrp, origin);
1018 	struct mfc6_cache *c;
1019 
1020 	list_for_each_entry(c, &mrt->mfc6_cache_array[line], list) {
1021 		if (ipv6_addr_equal(&c->mf6c_origin, origin) &&
1022 		    ipv6_addr_equal(&c->mf6c_mcastgrp, mcastgrp))
1023 			return c;
1024 	}
1025 	return NULL;
1026 }
1027 
1028 /* Look for a (*,*,oif) entry */
1029 static struct mfc6_cache *ip6mr_cache_find_any_parent(struct mr6_table *mrt,
1030 						      mifi_t mifi)
1031 {
1032 	int line = MFC6_HASH(&in6addr_any, &in6addr_any);
1033 	struct mfc6_cache *c;
1034 
1035 	list_for_each_entry(c, &mrt->mfc6_cache_array[line], list)
1036 		if (ipv6_addr_any(&c->mf6c_origin) &&
1037 		    ipv6_addr_any(&c->mf6c_mcastgrp) &&
1038 		    (c->mfc_un.res.ttls[mifi] < 255))
1039 			return c;
1040 
1041 	return NULL;
1042 }
1043 
1044 /* Look for a (*,G) entry */
1045 static struct mfc6_cache *ip6mr_cache_find_any(struct mr6_table *mrt,
1046 					       struct in6_addr *mcastgrp,
1047 					       mifi_t mifi)
1048 {
1049 	int line = MFC6_HASH(mcastgrp, &in6addr_any);
1050 	struct mfc6_cache *c, *proxy;
1051 
1052 	if (ipv6_addr_any(mcastgrp))
1053 		goto skip;
1054 
1055 	list_for_each_entry(c, &mrt->mfc6_cache_array[line], list)
1056 		if (ipv6_addr_any(&c->mf6c_origin) &&
1057 		    ipv6_addr_equal(&c->mf6c_mcastgrp, mcastgrp)) {
1058 			if (c->mfc_un.res.ttls[mifi] < 255)
1059 				return c;
1060 
1061 			/* It's ok if the mifi is part of the static tree */
1062 			proxy = ip6mr_cache_find_any_parent(mrt,
1063 							    c->mf6c_parent);
1064 			if (proxy && proxy->mfc_un.res.ttls[mifi] < 255)
1065 				return c;
1066 		}
1067 
1068 skip:
1069 	return ip6mr_cache_find_any_parent(mrt, mifi);
1070 }
1071 
1072 /*
1073  *	Allocate a multicast cache entry
1074  */
1075 static struct mfc6_cache *ip6mr_cache_alloc(void)
1076 {
1077 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
1078 	if (!c)
1079 		return NULL;
1080 	c->mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
1081 	c->mfc_un.res.minvif = MAXMIFS;
1082 	return c;
1083 }
1084 
1085 static struct mfc6_cache *ip6mr_cache_alloc_unres(void)
1086 {
1087 	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
1088 	if (!c)
1089 		return NULL;
1090 	skb_queue_head_init(&c->mfc_un.unres.unresolved);
1091 	c->mfc_un.unres.expires = jiffies + 10 * HZ;
1092 	return c;
1093 }
1094 
1095 /*
1096  *	A cache entry has gone into a resolved state from queued
1097  */
1098 
1099 static void ip6mr_cache_resolve(struct net *net, struct mr6_table *mrt,
1100 				struct mfc6_cache *uc, struct mfc6_cache *c)
1101 {
1102 	struct sk_buff *skb;
1103 
1104 	/*
1105 	 *	Play the pending entries through our router
1106 	 */
1107 
1108 	while ((skb = __skb_dequeue(&uc->mfc_un.unres.unresolved))) {
1109 		if (ipv6_hdr(skb)->version == 0) {
1110 			struct nlmsghdr *nlh = skb_pull(skb,
1111 							sizeof(struct ipv6hdr));
1112 
1113 			if (__ip6mr_fill_mroute(mrt, skb, c, nlmsg_data(nlh)) > 0) {
1114 				nlh->nlmsg_len = skb_tail_pointer(skb) - (u8 *)nlh;
1115 			} else {
1116 				nlh->nlmsg_type = NLMSG_ERROR;
1117 				nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
1118 				skb_trim(skb, nlh->nlmsg_len);
1119 				((struct nlmsgerr *)nlmsg_data(nlh))->error = -EMSGSIZE;
1120 			}
1121 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
1122 		} else
1123 			ip6_mr_forward(net, mrt, skb, c);
1124 	}
1125 }
1126 
1127 /*
1128  *	Bounce a cache query up to pim6sd and netlink.
1129  *
1130  *	Called under mrt_lock.
1131  */
1132 
1133 static int ip6mr_cache_report(struct mr6_table *mrt, struct sk_buff *pkt,
1134 			      mifi_t mifi, int assert)
1135 {
1136 	struct sk_buff *skb;
1137 	struct mrt6msg *msg;
1138 	int ret;
1139 
1140 #ifdef CONFIG_IPV6_PIMSM_V2
1141 	if (assert == MRT6MSG_WHOLEPKT)
1142 		skb = skb_realloc_headroom(pkt, -skb_network_offset(pkt)
1143 						+sizeof(*msg));
1144 	else
1145 #endif
1146 		skb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(*msg), GFP_ATOMIC);
1147 
1148 	if (!skb)
1149 		return -ENOBUFS;
1150 
1151 	/* I suppose that internal messages
1152 	 * do not require checksums */
1153 
1154 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1155 
1156 #ifdef CONFIG_IPV6_PIMSM_V2
1157 	if (assert == MRT6MSG_WHOLEPKT) {
1158 		/* Ugly, but we have no choice with this interface.
1159 		   Duplicate old header, fix length etc.
1160 		   And all this only to mangle msg->im6_msgtype and
1161 		   to set msg->im6_mbz to "mbz" :-)
1162 		 */
1163 		skb_push(skb, -skb_network_offset(pkt));
1164 
1165 		skb_push(skb, sizeof(*msg));
1166 		skb_reset_transport_header(skb);
1167 		msg = (struct mrt6msg *)skb_transport_header(skb);
1168 		msg->im6_mbz = 0;
1169 		msg->im6_msgtype = MRT6MSG_WHOLEPKT;
1170 		msg->im6_mif = mrt->mroute_reg_vif_num;
1171 		msg->im6_pad = 0;
1172 		msg->im6_src = ipv6_hdr(pkt)->saddr;
1173 		msg->im6_dst = ipv6_hdr(pkt)->daddr;
1174 
1175 		skb->ip_summed = CHECKSUM_UNNECESSARY;
1176 	} else
1177 #endif
1178 	{
1179 	/*
1180 	 *	Copy the IP header
1181 	 */
1182 
1183 	skb_put(skb, sizeof(struct ipv6hdr));
1184 	skb_reset_network_header(skb);
1185 	skb_copy_to_linear_data(skb, ipv6_hdr(pkt), sizeof(struct ipv6hdr));
1186 
1187 	/*
1188 	 *	Add our header
1189 	 */
1190 	skb_put(skb, sizeof(*msg));
1191 	skb_reset_transport_header(skb);
1192 	msg = (struct mrt6msg *)skb_transport_header(skb);
1193 
1194 	msg->im6_mbz = 0;
1195 	msg->im6_msgtype = assert;
1196 	msg->im6_mif = mifi;
1197 	msg->im6_pad = 0;
1198 	msg->im6_src = ipv6_hdr(pkt)->saddr;
1199 	msg->im6_dst = ipv6_hdr(pkt)->daddr;
1200 
1201 	skb_dst_set(skb, dst_clone(skb_dst(pkt)));
1202 	skb->ip_summed = CHECKSUM_UNNECESSARY;
1203 	}
1204 
1205 	if (!mrt->mroute6_sk) {
1206 		kfree_skb(skb);
1207 		return -EINVAL;
1208 	}
1209 
1210 	mrt6msg_netlink_event(mrt, skb);
1211 
1212 	/*
1213 	 *	Deliver to user space multicast routing algorithms
1214 	 */
1215 	ret = sock_queue_rcv_skb(mrt->mroute6_sk, skb);
1216 	if (ret < 0) {
1217 		net_warn_ratelimited("mroute6: pending queue full, dropping entries\n");
1218 		kfree_skb(skb);
1219 	}
1220 
1221 	return ret;
1222 }
1223 
1224 /*
1225  *	Queue a packet for resolution. It gets locked cache entry!
1226  */
1227 
1228 static int
1229 ip6mr_cache_unresolved(struct mr6_table *mrt, mifi_t mifi, struct sk_buff *skb)
1230 {
1231 	bool found = false;
1232 	int err;
1233 	struct mfc6_cache *c;
1234 
1235 	spin_lock_bh(&mfc_unres_lock);
1236 	list_for_each_entry(c, &mrt->mfc6_unres_queue, list) {
1237 		if (ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&
1238 		    ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr)) {
1239 			found = true;
1240 			break;
1241 		}
1242 	}
1243 
1244 	if (!found) {
1245 		/*
1246 		 *	Create a new entry if allowable
1247 		 */
1248 
1249 		if (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
1250 		    (c = ip6mr_cache_alloc_unres()) == NULL) {
1251 			spin_unlock_bh(&mfc_unres_lock);
1252 
1253 			kfree_skb(skb);
1254 			return -ENOBUFS;
1255 		}
1256 
1257 		/*
1258 		 *	Fill in the new cache entry
1259 		 */
1260 		c->mf6c_parent = -1;
1261 		c->mf6c_origin = ipv6_hdr(skb)->saddr;
1262 		c->mf6c_mcastgrp = ipv6_hdr(skb)->daddr;
1263 
1264 		/*
1265 		 *	Reflect first query at pim6sd
1266 		 */
1267 		err = ip6mr_cache_report(mrt, skb, mifi, MRT6MSG_NOCACHE);
1268 		if (err < 0) {
1269 			/* If the report failed throw the cache entry
1270 			   out - Brad Parker
1271 			 */
1272 			spin_unlock_bh(&mfc_unres_lock);
1273 
1274 			ip6mr_cache_free(c);
1275 			kfree_skb(skb);
1276 			return err;
1277 		}
1278 
1279 		atomic_inc(&mrt->cache_resolve_queue_len);
1280 		list_add(&c->list, &mrt->mfc6_unres_queue);
1281 		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1282 
1283 		ipmr_do_expire_process(mrt);
1284 	}
1285 
1286 	/*
1287 	 *	See if we can append the packet
1288 	 */
1289 	if (c->mfc_un.unres.unresolved.qlen > 3) {
1290 		kfree_skb(skb);
1291 		err = -ENOBUFS;
1292 	} else {
1293 		skb_queue_tail(&c->mfc_un.unres.unresolved, skb);
1294 		err = 0;
1295 	}
1296 
1297 	spin_unlock_bh(&mfc_unres_lock);
1298 	return err;
1299 }
1300 
1301 /*
1302  *	MFC6 cache manipulation by user space
1303  */
1304 
1305 static int ip6mr_mfc_delete(struct mr6_table *mrt, struct mf6cctl *mfc,
1306 			    int parent)
1307 {
1308 	int line;
1309 	struct mfc6_cache *c, *next;
1310 
1311 	line = MFC6_HASH(&mfc->mf6cc_mcastgrp.sin6_addr, &mfc->mf6cc_origin.sin6_addr);
1312 
1313 	list_for_each_entry_safe(c, next, &mrt->mfc6_cache_array[line], list) {
1314 		if (ipv6_addr_equal(&c->mf6c_origin, &mfc->mf6cc_origin.sin6_addr) &&
1315 		    ipv6_addr_equal(&c->mf6c_mcastgrp,
1316 				    &mfc->mf6cc_mcastgrp.sin6_addr) &&
1317 		    (parent == -1 || parent == c->mf6c_parent)) {
1318 			write_lock_bh(&mrt_lock);
1319 			list_del(&c->list);
1320 			write_unlock_bh(&mrt_lock);
1321 
1322 			mr6_netlink_event(mrt, c, RTM_DELROUTE);
1323 			ip6mr_cache_free(c);
1324 			return 0;
1325 		}
1326 	}
1327 	return -ENOENT;
1328 }
1329 
1330 static int ip6mr_device_event(struct notifier_block *this,
1331 			      unsigned long event, void *ptr)
1332 {
1333 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1334 	struct net *net = dev_net(dev);
1335 	struct mr6_table *mrt;
1336 	struct mif_device *v;
1337 	int ct;
1338 
1339 	if (event != NETDEV_UNREGISTER)
1340 		return NOTIFY_DONE;
1341 
1342 	ip6mr_for_each_table(mrt, net) {
1343 		v = &mrt->vif6_table[0];
1344 		for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1345 			if (v->dev == dev)
1346 				mif6_delete(mrt, ct, 1, NULL);
1347 		}
1348 	}
1349 
1350 	return NOTIFY_DONE;
1351 }
1352 
1353 static struct notifier_block ip6_mr_notifier = {
1354 	.notifier_call = ip6mr_device_event
1355 };
1356 
1357 /*
1358  *	Setup for IP multicast routing
1359  */
1360 
1361 static int __net_init ip6mr_net_init(struct net *net)
1362 {
1363 	int err;
1364 
1365 	err = ip6mr_rules_init(net);
1366 	if (err < 0)
1367 		goto fail;
1368 
1369 #ifdef CONFIG_PROC_FS
1370 	err = -ENOMEM;
1371 	if (!proc_create("ip6_mr_vif", 0, net->proc_net, &ip6mr_vif_fops))
1372 		goto proc_vif_fail;
1373 	if (!proc_create("ip6_mr_cache", 0, net->proc_net, &ip6mr_mfc_fops))
1374 		goto proc_cache_fail;
1375 #endif
1376 
1377 	return 0;
1378 
1379 #ifdef CONFIG_PROC_FS
1380 proc_cache_fail:
1381 	remove_proc_entry("ip6_mr_vif", net->proc_net);
1382 proc_vif_fail:
1383 	ip6mr_rules_exit(net);
1384 #endif
1385 fail:
1386 	return err;
1387 }
1388 
1389 static void __net_exit ip6mr_net_exit(struct net *net)
1390 {
1391 #ifdef CONFIG_PROC_FS
1392 	remove_proc_entry("ip6_mr_cache", net->proc_net);
1393 	remove_proc_entry("ip6_mr_vif", net->proc_net);
1394 #endif
1395 	ip6mr_rules_exit(net);
1396 }
1397 
1398 static struct pernet_operations ip6mr_net_ops = {
1399 	.init = ip6mr_net_init,
1400 	.exit = ip6mr_net_exit,
1401 };
1402 
1403 int __init ip6_mr_init(void)
1404 {
1405 	int err;
1406 
1407 	mrt_cachep = kmem_cache_create("ip6_mrt_cache",
1408 				       sizeof(struct mfc6_cache),
1409 				       0, SLAB_HWCACHE_ALIGN,
1410 				       NULL);
1411 	if (!mrt_cachep)
1412 		return -ENOMEM;
1413 
1414 	err = register_pernet_subsys(&ip6mr_net_ops);
1415 	if (err)
1416 		goto reg_pernet_fail;
1417 
1418 	err = register_netdevice_notifier(&ip6_mr_notifier);
1419 	if (err)
1420 		goto reg_notif_fail;
1421 #ifdef CONFIG_IPV6_PIMSM_V2
1422 	if (inet6_add_protocol(&pim6_protocol, IPPROTO_PIM) < 0) {
1423 		pr_err("%s: can't add PIM protocol\n", __func__);
1424 		err = -EAGAIN;
1425 		goto add_proto_fail;
1426 	}
1427 #endif
1428 	err = rtnl_register_module(THIS_MODULE, RTNL_FAMILY_IP6MR, RTM_GETROUTE,
1429 				   NULL, ip6mr_rtm_dumproute, 0);
1430 	if (err == 0)
1431 		return 0;
1432 
1433 #ifdef CONFIG_IPV6_PIMSM_V2
1434 	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
1435 add_proto_fail:
1436 	unregister_netdevice_notifier(&ip6_mr_notifier);
1437 #endif
1438 reg_notif_fail:
1439 	unregister_pernet_subsys(&ip6mr_net_ops);
1440 reg_pernet_fail:
1441 	kmem_cache_destroy(mrt_cachep);
1442 	return err;
1443 }
1444 
1445 void ip6_mr_cleanup(void)
1446 {
1447 	rtnl_unregister(RTNL_FAMILY_IP6MR, RTM_GETROUTE);
1448 #ifdef CONFIG_IPV6_PIMSM_V2
1449 	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
1450 #endif
1451 	unregister_netdevice_notifier(&ip6_mr_notifier);
1452 	unregister_pernet_subsys(&ip6mr_net_ops);
1453 	kmem_cache_destroy(mrt_cachep);
1454 }
1455 
1456 static int ip6mr_mfc_add(struct net *net, struct mr6_table *mrt,
1457 			 struct mf6cctl *mfc, int mrtsock, int parent)
1458 {
1459 	bool found = false;
1460 	int line;
1461 	struct mfc6_cache *uc, *c;
1462 	unsigned char ttls[MAXMIFS];
1463 	int i;
1464 
1465 	if (mfc->mf6cc_parent >= MAXMIFS)
1466 		return -ENFILE;
1467 
1468 	memset(ttls, 255, MAXMIFS);
1469 	for (i = 0; i < MAXMIFS; i++) {
1470 		if (IF_ISSET(i, &mfc->mf6cc_ifset))
1471 			ttls[i] = 1;
1472 
1473 	}
1474 
1475 	line = MFC6_HASH(&mfc->mf6cc_mcastgrp.sin6_addr, &mfc->mf6cc_origin.sin6_addr);
1476 
1477 	list_for_each_entry(c, &mrt->mfc6_cache_array[line], list) {
1478 		if (ipv6_addr_equal(&c->mf6c_origin, &mfc->mf6cc_origin.sin6_addr) &&
1479 		    ipv6_addr_equal(&c->mf6c_mcastgrp,
1480 				    &mfc->mf6cc_mcastgrp.sin6_addr) &&
1481 		    (parent == -1 || parent == mfc->mf6cc_parent)) {
1482 			found = true;
1483 			break;
1484 		}
1485 	}
1486 
1487 	if (found) {
1488 		write_lock_bh(&mrt_lock);
1489 		c->mf6c_parent = mfc->mf6cc_parent;
1490 		ip6mr_update_thresholds(mrt, c, ttls);
1491 		if (!mrtsock)
1492 			c->mfc_flags |= MFC_STATIC;
1493 		write_unlock_bh(&mrt_lock);
1494 		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1495 		return 0;
1496 	}
1497 
1498 	if (!ipv6_addr_any(&mfc->mf6cc_mcastgrp.sin6_addr) &&
1499 	    !ipv6_addr_is_multicast(&mfc->mf6cc_mcastgrp.sin6_addr))
1500 		return -EINVAL;
1501 
1502 	c = ip6mr_cache_alloc();
1503 	if (!c)
1504 		return -ENOMEM;
1505 
1506 	c->mf6c_origin = mfc->mf6cc_origin.sin6_addr;
1507 	c->mf6c_mcastgrp = mfc->mf6cc_mcastgrp.sin6_addr;
1508 	c->mf6c_parent = mfc->mf6cc_parent;
1509 	ip6mr_update_thresholds(mrt, c, ttls);
1510 	if (!mrtsock)
1511 		c->mfc_flags |= MFC_STATIC;
1512 
1513 	write_lock_bh(&mrt_lock);
1514 	list_add(&c->list, &mrt->mfc6_cache_array[line]);
1515 	write_unlock_bh(&mrt_lock);
1516 
1517 	/*
1518 	 *	Check to see if we resolved a queued list. If so we
1519 	 *	need to send on the frames and tidy up.
1520 	 */
1521 	found = false;
1522 	spin_lock_bh(&mfc_unres_lock);
1523 	list_for_each_entry(uc, &mrt->mfc6_unres_queue, list) {
1524 		if (ipv6_addr_equal(&uc->mf6c_origin, &c->mf6c_origin) &&
1525 		    ipv6_addr_equal(&uc->mf6c_mcastgrp, &c->mf6c_mcastgrp)) {
1526 			list_del(&uc->list);
1527 			atomic_dec(&mrt->cache_resolve_queue_len);
1528 			found = true;
1529 			break;
1530 		}
1531 	}
1532 	if (list_empty(&mrt->mfc6_unres_queue))
1533 		del_timer(&mrt->ipmr_expire_timer);
1534 	spin_unlock_bh(&mfc_unres_lock);
1535 
1536 	if (found) {
1537 		ip6mr_cache_resolve(net, mrt, uc, c);
1538 		ip6mr_cache_free(uc);
1539 	}
1540 	mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1541 	return 0;
1542 }
1543 
1544 /*
1545  *	Close the multicast socket, and clear the vif tables etc
1546  */
1547 
1548 static void mroute_clean_tables(struct mr6_table *mrt, bool all)
1549 {
1550 	int i;
1551 	LIST_HEAD(list);
1552 	struct mfc6_cache *c, *next;
1553 
1554 	/*
1555 	 *	Shut down all active vif entries
1556 	 */
1557 	for (i = 0; i < mrt->maxvif; i++) {
1558 		if (!all && (mrt->vif6_table[i].flags & VIFF_STATIC))
1559 			continue;
1560 		mif6_delete(mrt, i, 0, &list);
1561 	}
1562 	unregister_netdevice_many(&list);
1563 
1564 	/*
1565 	 *	Wipe the cache
1566 	 */
1567 	for (i = 0; i < MFC6_LINES; i++) {
1568 		list_for_each_entry_safe(c, next, &mrt->mfc6_cache_array[i], list) {
1569 			if (!all && (c->mfc_flags & MFC_STATIC))
1570 				continue;
1571 			write_lock_bh(&mrt_lock);
1572 			list_del(&c->list);
1573 			write_unlock_bh(&mrt_lock);
1574 
1575 			mr6_netlink_event(mrt, c, RTM_DELROUTE);
1576 			ip6mr_cache_free(c);
1577 		}
1578 	}
1579 
1580 	if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1581 		spin_lock_bh(&mfc_unres_lock);
1582 		list_for_each_entry_safe(c, next, &mrt->mfc6_unres_queue, list) {
1583 			list_del(&c->list);
1584 			mr6_netlink_event(mrt, c, RTM_DELROUTE);
1585 			ip6mr_destroy_unres(mrt, c);
1586 		}
1587 		spin_unlock_bh(&mfc_unres_lock);
1588 	}
1589 }
1590 
1591 static int ip6mr_sk_init(struct mr6_table *mrt, struct sock *sk)
1592 {
1593 	int err = 0;
1594 	struct net *net = sock_net(sk);
1595 
1596 	rtnl_lock();
1597 	write_lock_bh(&mrt_lock);
1598 	if (likely(mrt->mroute6_sk == NULL)) {
1599 		mrt->mroute6_sk = sk;
1600 		net->ipv6.devconf_all->mc_forwarding++;
1601 	} else {
1602 		err = -EADDRINUSE;
1603 	}
1604 	write_unlock_bh(&mrt_lock);
1605 
1606 	if (!err)
1607 		inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
1608 					     NETCONFA_MC_FORWARDING,
1609 					     NETCONFA_IFINDEX_ALL,
1610 					     net->ipv6.devconf_all);
1611 	rtnl_unlock();
1612 
1613 	return err;
1614 }
1615 
1616 int ip6mr_sk_done(struct sock *sk)
1617 {
1618 	int err = -EACCES;
1619 	struct net *net = sock_net(sk);
1620 	struct mr6_table *mrt;
1621 
1622 	if (sk->sk_type != SOCK_RAW ||
1623 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1624 		return err;
1625 
1626 	rtnl_lock();
1627 	ip6mr_for_each_table(mrt, net) {
1628 		if (sk == mrt->mroute6_sk) {
1629 			write_lock_bh(&mrt_lock);
1630 			mrt->mroute6_sk = NULL;
1631 			net->ipv6.devconf_all->mc_forwarding--;
1632 			write_unlock_bh(&mrt_lock);
1633 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
1634 						     NETCONFA_MC_FORWARDING,
1635 						     NETCONFA_IFINDEX_ALL,
1636 						     net->ipv6.devconf_all);
1637 
1638 			mroute_clean_tables(mrt, false);
1639 			err = 0;
1640 			break;
1641 		}
1642 	}
1643 	rtnl_unlock();
1644 
1645 	return err;
1646 }
1647 
1648 struct sock *mroute6_socket(struct net *net, struct sk_buff *skb)
1649 {
1650 	struct mr6_table *mrt;
1651 	struct flowi6 fl6 = {
1652 		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
1653 		.flowi6_oif	= skb->dev->ifindex,
1654 		.flowi6_mark	= skb->mark,
1655 	};
1656 
1657 	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
1658 		return NULL;
1659 
1660 	return mrt->mroute6_sk;
1661 }
1662 
1663 /*
1664  *	Socket options and virtual interface manipulation. The whole
1665  *	virtual interface system is a complete heap, but unfortunately
1666  *	that's how BSD mrouted happens to think. Maybe one day with a proper
1667  *	MOSPF/PIM router set up we can clean this up.
1668  */
1669 
1670 int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsigned int optlen)
1671 {
1672 	int ret, parent = 0;
1673 	struct mif6ctl vif;
1674 	struct mf6cctl mfc;
1675 	mifi_t mifi;
1676 	struct net *net = sock_net(sk);
1677 	struct mr6_table *mrt;
1678 
1679 	if (sk->sk_type != SOCK_RAW ||
1680 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1681 		return -EOPNOTSUPP;
1682 
1683 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1684 	if (!mrt)
1685 		return -ENOENT;
1686 
1687 	if (optname != MRT6_INIT) {
1688 		if (sk != mrt->mroute6_sk && !ns_capable(net->user_ns, CAP_NET_ADMIN))
1689 			return -EACCES;
1690 	}
1691 
1692 	switch (optname) {
1693 	case MRT6_INIT:
1694 		if (optlen < sizeof(int))
1695 			return -EINVAL;
1696 
1697 		return ip6mr_sk_init(mrt, sk);
1698 
1699 	case MRT6_DONE:
1700 		return ip6mr_sk_done(sk);
1701 
1702 	case MRT6_ADD_MIF:
1703 		if (optlen < sizeof(vif))
1704 			return -EINVAL;
1705 		if (copy_from_user(&vif, optval, sizeof(vif)))
1706 			return -EFAULT;
1707 		if (vif.mif6c_mifi >= MAXMIFS)
1708 			return -ENFILE;
1709 		rtnl_lock();
1710 		ret = mif6_add(net, mrt, &vif, sk == mrt->mroute6_sk);
1711 		rtnl_unlock();
1712 		return ret;
1713 
1714 	case MRT6_DEL_MIF:
1715 		if (optlen < sizeof(mifi_t))
1716 			return -EINVAL;
1717 		if (copy_from_user(&mifi, optval, sizeof(mifi_t)))
1718 			return -EFAULT;
1719 		rtnl_lock();
1720 		ret = mif6_delete(mrt, mifi, 0, NULL);
1721 		rtnl_unlock();
1722 		return ret;
1723 
1724 	/*
1725 	 *	Manipulate the forwarding caches. These live
1726 	 *	in a sort of kernel/user symbiosis.
1727 	 */
1728 	case MRT6_ADD_MFC:
1729 	case MRT6_DEL_MFC:
1730 		parent = -1;
1731 		/* fall through */
1732 	case MRT6_ADD_MFC_PROXY:
1733 	case MRT6_DEL_MFC_PROXY:
1734 		if (optlen < sizeof(mfc))
1735 			return -EINVAL;
1736 		if (copy_from_user(&mfc, optval, sizeof(mfc)))
1737 			return -EFAULT;
1738 		if (parent == 0)
1739 			parent = mfc.mf6cc_parent;
1740 		rtnl_lock();
1741 		if (optname == MRT6_DEL_MFC || optname == MRT6_DEL_MFC_PROXY)
1742 			ret = ip6mr_mfc_delete(mrt, &mfc, parent);
1743 		else
1744 			ret = ip6mr_mfc_add(net, mrt, &mfc,
1745 					    sk == mrt->mroute6_sk, parent);
1746 		rtnl_unlock();
1747 		return ret;
1748 
1749 	/*
1750 	 *	Control PIM assert (to activate pim will activate assert)
1751 	 */
1752 	case MRT6_ASSERT:
1753 	{
1754 		int v;
1755 
1756 		if (optlen != sizeof(v))
1757 			return -EINVAL;
1758 		if (get_user(v, (int __user *)optval))
1759 			return -EFAULT;
1760 		mrt->mroute_do_assert = v;
1761 		return 0;
1762 	}
1763 
1764 #ifdef CONFIG_IPV6_PIMSM_V2
1765 	case MRT6_PIM:
1766 	{
1767 		int v;
1768 
1769 		if (optlen != sizeof(v))
1770 			return -EINVAL;
1771 		if (get_user(v, (int __user *)optval))
1772 			return -EFAULT;
1773 		v = !!v;
1774 		rtnl_lock();
1775 		ret = 0;
1776 		if (v != mrt->mroute_do_pim) {
1777 			mrt->mroute_do_pim = v;
1778 			mrt->mroute_do_assert = v;
1779 		}
1780 		rtnl_unlock();
1781 		return ret;
1782 	}
1783 
1784 #endif
1785 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
1786 	case MRT6_TABLE:
1787 	{
1788 		u32 v;
1789 
1790 		if (optlen != sizeof(u32))
1791 			return -EINVAL;
1792 		if (get_user(v, (u32 __user *)optval))
1793 			return -EFAULT;
1794 		/* "pim6reg%u" should not exceed 16 bytes (IFNAMSIZ) */
1795 		if (v != RT_TABLE_DEFAULT && v >= 100000000)
1796 			return -EINVAL;
1797 		if (sk == mrt->mroute6_sk)
1798 			return -EBUSY;
1799 
1800 		rtnl_lock();
1801 		ret = 0;
1802 		if (!ip6mr_new_table(net, v))
1803 			ret = -ENOMEM;
1804 		raw6_sk(sk)->ip6mr_table = v;
1805 		rtnl_unlock();
1806 		return ret;
1807 	}
1808 #endif
1809 	/*
1810 	 *	Spurious command, or MRT6_VERSION which you cannot
1811 	 *	set.
1812 	 */
1813 	default:
1814 		return -ENOPROTOOPT;
1815 	}
1816 }
1817 
1818 /*
1819  *	Getsock opt support for the multicast routing system.
1820  */
1821 
1822 int ip6_mroute_getsockopt(struct sock *sk, int optname, char __user *optval,
1823 			  int __user *optlen)
1824 {
1825 	int olr;
1826 	int val;
1827 	struct net *net = sock_net(sk);
1828 	struct mr6_table *mrt;
1829 
1830 	if (sk->sk_type != SOCK_RAW ||
1831 	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1832 		return -EOPNOTSUPP;
1833 
1834 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1835 	if (!mrt)
1836 		return -ENOENT;
1837 
1838 	switch (optname) {
1839 	case MRT6_VERSION:
1840 		val = 0x0305;
1841 		break;
1842 #ifdef CONFIG_IPV6_PIMSM_V2
1843 	case MRT6_PIM:
1844 		val = mrt->mroute_do_pim;
1845 		break;
1846 #endif
1847 	case MRT6_ASSERT:
1848 		val = mrt->mroute_do_assert;
1849 		break;
1850 	default:
1851 		return -ENOPROTOOPT;
1852 	}
1853 
1854 	if (get_user(olr, optlen))
1855 		return -EFAULT;
1856 
1857 	olr = min_t(int, olr, sizeof(int));
1858 	if (olr < 0)
1859 		return -EINVAL;
1860 
1861 	if (put_user(olr, optlen))
1862 		return -EFAULT;
1863 	if (copy_to_user(optval, &val, olr))
1864 		return -EFAULT;
1865 	return 0;
1866 }
1867 
1868 /*
1869  *	The IP multicast ioctl support routines.
1870  */
1871 
1872 int ip6mr_ioctl(struct sock *sk, int cmd, void __user *arg)
1873 {
1874 	struct sioc_sg_req6 sr;
1875 	struct sioc_mif_req6 vr;
1876 	struct mif_device *vif;
1877 	struct mfc6_cache *c;
1878 	struct net *net = sock_net(sk);
1879 	struct mr6_table *mrt;
1880 
1881 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1882 	if (!mrt)
1883 		return -ENOENT;
1884 
1885 	switch (cmd) {
1886 	case SIOCGETMIFCNT_IN6:
1887 		if (copy_from_user(&vr, arg, sizeof(vr)))
1888 			return -EFAULT;
1889 		if (vr.mifi >= mrt->maxvif)
1890 			return -EINVAL;
1891 		read_lock(&mrt_lock);
1892 		vif = &mrt->vif6_table[vr.mifi];
1893 		if (MIF_EXISTS(mrt, vr.mifi)) {
1894 			vr.icount = vif->pkt_in;
1895 			vr.ocount = vif->pkt_out;
1896 			vr.ibytes = vif->bytes_in;
1897 			vr.obytes = vif->bytes_out;
1898 			read_unlock(&mrt_lock);
1899 
1900 			if (copy_to_user(arg, &vr, sizeof(vr)))
1901 				return -EFAULT;
1902 			return 0;
1903 		}
1904 		read_unlock(&mrt_lock);
1905 		return -EADDRNOTAVAIL;
1906 	case SIOCGETSGCNT_IN6:
1907 		if (copy_from_user(&sr, arg, sizeof(sr)))
1908 			return -EFAULT;
1909 
1910 		read_lock(&mrt_lock);
1911 		c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
1912 		if (c) {
1913 			sr.pktcnt = c->mfc_un.res.pkt;
1914 			sr.bytecnt = c->mfc_un.res.bytes;
1915 			sr.wrong_if = c->mfc_un.res.wrong_if;
1916 			read_unlock(&mrt_lock);
1917 
1918 			if (copy_to_user(arg, &sr, sizeof(sr)))
1919 				return -EFAULT;
1920 			return 0;
1921 		}
1922 		read_unlock(&mrt_lock);
1923 		return -EADDRNOTAVAIL;
1924 	default:
1925 		return -ENOIOCTLCMD;
1926 	}
1927 }
1928 
1929 #ifdef CONFIG_COMPAT
1930 struct compat_sioc_sg_req6 {
1931 	struct sockaddr_in6 src;
1932 	struct sockaddr_in6 grp;
1933 	compat_ulong_t pktcnt;
1934 	compat_ulong_t bytecnt;
1935 	compat_ulong_t wrong_if;
1936 };
1937 
1938 struct compat_sioc_mif_req6 {
1939 	mifi_t	mifi;
1940 	compat_ulong_t icount;
1941 	compat_ulong_t ocount;
1942 	compat_ulong_t ibytes;
1943 	compat_ulong_t obytes;
1944 };
1945 
1946 int ip6mr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1947 {
1948 	struct compat_sioc_sg_req6 sr;
1949 	struct compat_sioc_mif_req6 vr;
1950 	struct mif_device *vif;
1951 	struct mfc6_cache *c;
1952 	struct net *net = sock_net(sk);
1953 	struct mr6_table *mrt;
1954 
1955 	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
1956 	if (!mrt)
1957 		return -ENOENT;
1958 
1959 	switch (cmd) {
1960 	case SIOCGETMIFCNT_IN6:
1961 		if (copy_from_user(&vr, arg, sizeof(vr)))
1962 			return -EFAULT;
1963 		if (vr.mifi >= mrt->maxvif)
1964 			return -EINVAL;
1965 		read_lock(&mrt_lock);
1966 		vif = &mrt->vif6_table[vr.mifi];
1967 		if (MIF_EXISTS(mrt, vr.mifi)) {
1968 			vr.icount = vif->pkt_in;
1969 			vr.ocount = vif->pkt_out;
1970 			vr.ibytes = vif->bytes_in;
1971 			vr.obytes = vif->bytes_out;
1972 			read_unlock(&mrt_lock);
1973 
1974 			if (copy_to_user(arg, &vr, sizeof(vr)))
1975 				return -EFAULT;
1976 			return 0;
1977 		}
1978 		read_unlock(&mrt_lock);
1979 		return -EADDRNOTAVAIL;
1980 	case SIOCGETSGCNT_IN6:
1981 		if (copy_from_user(&sr, arg, sizeof(sr)))
1982 			return -EFAULT;
1983 
1984 		read_lock(&mrt_lock);
1985 		c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
1986 		if (c) {
1987 			sr.pktcnt = c->mfc_un.res.pkt;
1988 			sr.bytecnt = c->mfc_un.res.bytes;
1989 			sr.wrong_if = c->mfc_un.res.wrong_if;
1990 			read_unlock(&mrt_lock);
1991 
1992 			if (copy_to_user(arg, &sr, sizeof(sr)))
1993 				return -EFAULT;
1994 			return 0;
1995 		}
1996 		read_unlock(&mrt_lock);
1997 		return -EADDRNOTAVAIL;
1998 	default:
1999 		return -ENOIOCTLCMD;
2000 	}
2001 }
2002 #endif
2003 
2004 static inline int ip6mr_forward2_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
2005 {
2006 	__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
2007 			IPSTATS_MIB_OUTFORWDATAGRAMS);
2008 	__IP6_ADD_STATS(net, ip6_dst_idev(skb_dst(skb)),
2009 			IPSTATS_MIB_OUTOCTETS, skb->len);
2010 	return dst_output(net, sk, skb);
2011 }
2012 
2013 /*
2014  *	Processing handlers for ip6mr_forward
2015  */
2016 
2017 static int ip6mr_forward2(struct net *net, struct mr6_table *mrt,
2018 			  struct sk_buff *skb, struct mfc6_cache *c, int vifi)
2019 {
2020 	struct ipv6hdr *ipv6h;
2021 	struct mif_device *vif = &mrt->vif6_table[vifi];
2022 	struct net_device *dev;
2023 	struct dst_entry *dst;
2024 	struct flowi6 fl6;
2025 
2026 	if (!vif->dev)
2027 		goto out_free;
2028 
2029 #ifdef CONFIG_IPV6_PIMSM_V2
2030 	if (vif->flags & MIFF_REGISTER) {
2031 		vif->pkt_out++;
2032 		vif->bytes_out += skb->len;
2033 		vif->dev->stats.tx_bytes += skb->len;
2034 		vif->dev->stats.tx_packets++;
2035 		ip6mr_cache_report(mrt, skb, vifi, MRT6MSG_WHOLEPKT);
2036 		goto out_free;
2037 	}
2038 #endif
2039 
2040 	ipv6h = ipv6_hdr(skb);
2041 
2042 	fl6 = (struct flowi6) {
2043 		.flowi6_oif = vif->link,
2044 		.daddr = ipv6h->daddr,
2045 	};
2046 
2047 	dst = ip6_route_output(net, NULL, &fl6);
2048 	if (dst->error) {
2049 		dst_release(dst);
2050 		goto out_free;
2051 	}
2052 
2053 	skb_dst_drop(skb);
2054 	skb_dst_set(skb, dst);
2055 
2056 	/*
2057 	 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
2058 	 * not only before forwarding, but after forwarding on all output
2059 	 * interfaces. It is clear, if mrouter runs a multicasting
2060 	 * program, it should receive packets not depending to what interface
2061 	 * program is joined.
2062 	 * If we will not make it, the program will have to join on all
2063 	 * interfaces. On the other hand, multihoming host (or router, but
2064 	 * not mrouter) cannot join to more than one interface - it will
2065 	 * result in receiving multiple packets.
2066 	 */
2067 	dev = vif->dev;
2068 	skb->dev = dev;
2069 	vif->pkt_out++;
2070 	vif->bytes_out += skb->len;
2071 
2072 	/* We are about to write */
2073 	/* XXX: extension headers? */
2074 	if (skb_cow(skb, sizeof(*ipv6h) + LL_RESERVED_SPACE(dev)))
2075 		goto out_free;
2076 
2077 	ipv6h = ipv6_hdr(skb);
2078 	ipv6h->hop_limit--;
2079 
2080 	IP6CB(skb)->flags |= IP6SKB_FORWARDED;
2081 
2082 	return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
2083 		       net, NULL, skb, skb->dev, dev,
2084 		       ip6mr_forward2_finish);
2085 
2086 out_free:
2087 	kfree_skb(skb);
2088 	return 0;
2089 }
2090 
2091 static int ip6mr_find_vif(struct mr6_table *mrt, struct net_device *dev)
2092 {
2093 	int ct;
2094 
2095 	for (ct = mrt->maxvif - 1; ct >= 0; ct--) {
2096 		if (mrt->vif6_table[ct].dev == dev)
2097 			break;
2098 	}
2099 	return ct;
2100 }
2101 
2102 static void ip6_mr_forward(struct net *net, struct mr6_table *mrt,
2103 			   struct sk_buff *skb, struct mfc6_cache *cache)
2104 {
2105 	int psend = -1;
2106 	int vif, ct;
2107 	int true_vifi = ip6mr_find_vif(mrt, skb->dev);
2108 
2109 	vif = cache->mf6c_parent;
2110 	cache->mfc_un.res.pkt++;
2111 	cache->mfc_un.res.bytes += skb->len;
2112 	cache->mfc_un.res.lastuse = jiffies;
2113 
2114 	if (ipv6_addr_any(&cache->mf6c_origin) && true_vifi >= 0) {
2115 		struct mfc6_cache *cache_proxy;
2116 
2117 		/* For an (*,G) entry, we only check that the incoming
2118 		 * interface is part of the static tree.
2119 		 */
2120 		cache_proxy = ip6mr_cache_find_any_parent(mrt, vif);
2121 		if (cache_proxy &&
2122 		    cache_proxy->mfc_un.res.ttls[true_vifi] < 255)
2123 			goto forward;
2124 	}
2125 
2126 	/*
2127 	 * Wrong interface: drop packet and (maybe) send PIM assert.
2128 	 */
2129 	if (mrt->vif6_table[vif].dev != skb->dev) {
2130 		cache->mfc_un.res.wrong_if++;
2131 
2132 		if (true_vifi >= 0 && mrt->mroute_do_assert &&
2133 		    /* pimsm uses asserts, when switching from RPT to SPT,
2134 		       so that we cannot check that packet arrived on an oif.
2135 		       It is bad, but otherwise we would need to move pretty
2136 		       large chunk of pimd to kernel. Ough... --ANK
2137 		     */
2138 		    (mrt->mroute_do_pim ||
2139 		     cache->mfc_un.res.ttls[true_vifi] < 255) &&
2140 		    time_after(jiffies,
2141 			       cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) {
2142 			cache->mfc_un.res.last_assert = jiffies;
2143 			ip6mr_cache_report(mrt, skb, true_vifi, MRT6MSG_WRONGMIF);
2144 		}
2145 		goto dont_forward;
2146 	}
2147 
2148 forward:
2149 	mrt->vif6_table[vif].pkt_in++;
2150 	mrt->vif6_table[vif].bytes_in += skb->len;
2151 
2152 	/*
2153 	 *	Forward the frame
2154 	 */
2155 	if (ipv6_addr_any(&cache->mf6c_origin) &&
2156 	    ipv6_addr_any(&cache->mf6c_mcastgrp)) {
2157 		if (true_vifi >= 0 &&
2158 		    true_vifi != cache->mf6c_parent &&
2159 		    ipv6_hdr(skb)->hop_limit >
2160 				cache->mfc_un.res.ttls[cache->mf6c_parent]) {
2161 			/* It's an (*,*) entry and the packet is not coming from
2162 			 * the upstream: forward the packet to the upstream
2163 			 * only.
2164 			 */
2165 			psend = cache->mf6c_parent;
2166 			goto last_forward;
2167 		}
2168 		goto dont_forward;
2169 	}
2170 	for (ct = cache->mfc_un.res.maxvif - 1; ct >= cache->mfc_un.res.minvif; ct--) {
2171 		/* For (*,G) entry, don't forward to the incoming interface */
2172 		if ((!ipv6_addr_any(&cache->mf6c_origin) || ct != true_vifi) &&
2173 		    ipv6_hdr(skb)->hop_limit > cache->mfc_un.res.ttls[ct]) {
2174 			if (psend != -1) {
2175 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2176 				if (skb2)
2177 					ip6mr_forward2(net, mrt, skb2, cache, psend);
2178 			}
2179 			psend = ct;
2180 		}
2181 	}
2182 last_forward:
2183 	if (psend != -1) {
2184 		ip6mr_forward2(net, mrt, skb, cache, psend);
2185 		return;
2186 	}
2187 
2188 dont_forward:
2189 	kfree_skb(skb);
2190 }
2191 
2192 
2193 /*
2194  *	Multicast packets for forwarding arrive here
2195  */
2196 
2197 int ip6_mr_input(struct sk_buff *skb)
2198 {
2199 	struct mfc6_cache *cache;
2200 	struct net *net = dev_net(skb->dev);
2201 	struct mr6_table *mrt;
2202 	struct flowi6 fl6 = {
2203 		.flowi6_iif	= skb->dev->ifindex,
2204 		.flowi6_mark	= skb->mark,
2205 	};
2206 	int err;
2207 
2208 	err = ip6mr_fib_lookup(net, &fl6, &mrt);
2209 	if (err < 0) {
2210 		kfree_skb(skb);
2211 		return err;
2212 	}
2213 
2214 	read_lock(&mrt_lock);
2215 	cache = ip6mr_cache_find(mrt,
2216 				 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr);
2217 	if (!cache) {
2218 		int vif = ip6mr_find_vif(mrt, skb->dev);
2219 
2220 		if (vif >= 0)
2221 			cache = ip6mr_cache_find_any(mrt,
2222 						     &ipv6_hdr(skb)->daddr,
2223 						     vif);
2224 	}
2225 
2226 	/*
2227 	 *	No usable cache entry
2228 	 */
2229 	if (!cache) {
2230 		int vif;
2231 
2232 		vif = ip6mr_find_vif(mrt, skb->dev);
2233 		if (vif >= 0) {
2234 			int err = ip6mr_cache_unresolved(mrt, vif, skb);
2235 			read_unlock(&mrt_lock);
2236 
2237 			return err;
2238 		}
2239 		read_unlock(&mrt_lock);
2240 		kfree_skb(skb);
2241 		return -ENODEV;
2242 	}
2243 
2244 	ip6_mr_forward(net, mrt, skb, cache);
2245 
2246 	read_unlock(&mrt_lock);
2247 
2248 	return 0;
2249 }
2250 
2251 
2252 static int __ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
2253 			       struct mfc6_cache *c, struct rtmsg *rtm)
2254 {
2255 	struct rta_mfc_stats mfcs;
2256 	struct nlattr *mp_attr;
2257 	struct rtnexthop *nhp;
2258 	unsigned long lastuse;
2259 	int ct;
2260 
2261 	/* If cache is unresolved, don't try to parse IIF and OIF */
2262 	if (c->mf6c_parent >= MAXMIFS) {
2263 		rtm->rtm_flags |= RTNH_F_UNRESOLVED;
2264 		return -ENOENT;
2265 	}
2266 
2267 	if (MIF_EXISTS(mrt, c->mf6c_parent) &&
2268 	    nla_put_u32(skb, RTA_IIF, mrt->vif6_table[c->mf6c_parent].dev->ifindex) < 0)
2269 		return -EMSGSIZE;
2270 	mp_attr = nla_nest_start(skb, RTA_MULTIPATH);
2271 	if (!mp_attr)
2272 		return -EMSGSIZE;
2273 
2274 	for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
2275 		if (MIF_EXISTS(mrt, ct) && c->mfc_un.res.ttls[ct] < 255) {
2276 			nhp = nla_reserve_nohdr(skb, sizeof(*nhp));
2277 			if (!nhp) {
2278 				nla_nest_cancel(skb, mp_attr);
2279 				return -EMSGSIZE;
2280 			}
2281 
2282 			nhp->rtnh_flags = 0;
2283 			nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
2284 			nhp->rtnh_ifindex = mrt->vif6_table[ct].dev->ifindex;
2285 			nhp->rtnh_len = sizeof(*nhp);
2286 		}
2287 	}
2288 
2289 	nla_nest_end(skb, mp_attr);
2290 
2291 	lastuse = READ_ONCE(c->mfc_un.res.lastuse);
2292 	lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0;
2293 
2294 	mfcs.mfcs_packets = c->mfc_un.res.pkt;
2295 	mfcs.mfcs_bytes = c->mfc_un.res.bytes;
2296 	mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
2297 	if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) ||
2298 	    nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse),
2299 			      RTA_PAD))
2300 		return -EMSGSIZE;
2301 
2302 	rtm->rtm_type = RTN_MULTICAST;
2303 	return 1;
2304 }
2305 
2306 int ip6mr_get_route(struct net *net, struct sk_buff *skb, struct rtmsg *rtm,
2307 		    u32 portid)
2308 {
2309 	int err;
2310 	struct mr6_table *mrt;
2311 	struct mfc6_cache *cache;
2312 	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
2313 
2314 	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
2315 	if (!mrt)
2316 		return -ENOENT;
2317 
2318 	read_lock(&mrt_lock);
2319 	cache = ip6mr_cache_find(mrt, &rt->rt6i_src.addr, &rt->rt6i_dst.addr);
2320 	if (!cache && skb->dev) {
2321 		int vif = ip6mr_find_vif(mrt, skb->dev);
2322 
2323 		if (vif >= 0)
2324 			cache = ip6mr_cache_find_any(mrt, &rt->rt6i_dst.addr,
2325 						     vif);
2326 	}
2327 
2328 	if (!cache) {
2329 		struct sk_buff *skb2;
2330 		struct ipv6hdr *iph;
2331 		struct net_device *dev;
2332 		int vif;
2333 
2334 		dev = skb->dev;
2335 		if (!dev || (vif = ip6mr_find_vif(mrt, dev)) < 0) {
2336 			read_unlock(&mrt_lock);
2337 			return -ENODEV;
2338 		}
2339 
2340 		/* really correct? */
2341 		skb2 = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
2342 		if (!skb2) {
2343 			read_unlock(&mrt_lock);
2344 			return -ENOMEM;
2345 		}
2346 
2347 		NETLINK_CB(skb2).portid = portid;
2348 		skb_reset_transport_header(skb2);
2349 
2350 		skb_put(skb2, sizeof(struct ipv6hdr));
2351 		skb_reset_network_header(skb2);
2352 
2353 		iph = ipv6_hdr(skb2);
2354 		iph->version = 0;
2355 		iph->priority = 0;
2356 		iph->flow_lbl[0] = 0;
2357 		iph->flow_lbl[1] = 0;
2358 		iph->flow_lbl[2] = 0;
2359 		iph->payload_len = 0;
2360 		iph->nexthdr = IPPROTO_NONE;
2361 		iph->hop_limit = 0;
2362 		iph->saddr = rt->rt6i_src.addr;
2363 		iph->daddr = rt->rt6i_dst.addr;
2364 
2365 		err = ip6mr_cache_unresolved(mrt, vif, skb2);
2366 		read_unlock(&mrt_lock);
2367 
2368 		return err;
2369 	}
2370 
2371 	if (rtm->rtm_flags & RTM_F_NOTIFY)
2372 		cache->mfc_flags |= MFC_NOTIFY;
2373 
2374 	err = __ip6mr_fill_mroute(mrt, skb, cache, rtm);
2375 	read_unlock(&mrt_lock);
2376 	return err;
2377 }
2378 
2379 static int ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
2380 			     u32 portid, u32 seq, struct mfc6_cache *c, int cmd,
2381 			     int flags)
2382 {
2383 	struct nlmsghdr *nlh;
2384 	struct rtmsg *rtm;
2385 	int err;
2386 
2387 	nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2388 	if (!nlh)
2389 		return -EMSGSIZE;
2390 
2391 	rtm = nlmsg_data(nlh);
2392 	rtm->rtm_family   = RTNL_FAMILY_IP6MR;
2393 	rtm->rtm_dst_len  = 128;
2394 	rtm->rtm_src_len  = 128;
2395 	rtm->rtm_tos      = 0;
2396 	rtm->rtm_table    = mrt->id;
2397 	if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2398 		goto nla_put_failure;
2399 	rtm->rtm_type = RTN_MULTICAST;
2400 	rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2401 	if (c->mfc_flags & MFC_STATIC)
2402 		rtm->rtm_protocol = RTPROT_STATIC;
2403 	else
2404 		rtm->rtm_protocol = RTPROT_MROUTED;
2405 	rtm->rtm_flags    = 0;
2406 
2407 	if (nla_put_in6_addr(skb, RTA_SRC, &c->mf6c_origin) ||
2408 	    nla_put_in6_addr(skb, RTA_DST, &c->mf6c_mcastgrp))
2409 		goto nla_put_failure;
2410 	err = __ip6mr_fill_mroute(mrt, skb, c, rtm);
2411 	/* do not break the dump if cache is unresolved */
2412 	if (err < 0 && err != -ENOENT)
2413 		goto nla_put_failure;
2414 
2415 	nlmsg_end(skb, nlh);
2416 	return 0;
2417 
2418 nla_put_failure:
2419 	nlmsg_cancel(skb, nlh);
2420 	return -EMSGSIZE;
2421 }
2422 
2423 static int mr6_msgsize(bool unresolved, int maxvif)
2424 {
2425 	size_t len =
2426 		NLMSG_ALIGN(sizeof(struct rtmsg))
2427 		+ nla_total_size(4)	/* RTA_TABLE */
2428 		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_SRC */
2429 		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_DST */
2430 		;
2431 
2432 	if (!unresolved)
2433 		len = len
2434 		      + nla_total_size(4)	/* RTA_IIF */
2435 		      + nla_total_size(0)	/* RTA_MULTIPATH */
2436 		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2437 						/* RTA_MFC_STATS */
2438 		      + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
2439 		;
2440 
2441 	return len;
2442 }
2443 
2444 static void mr6_netlink_event(struct mr6_table *mrt, struct mfc6_cache *mfc,
2445 			      int cmd)
2446 {
2447 	struct net *net = read_pnet(&mrt->net);
2448 	struct sk_buff *skb;
2449 	int err = -ENOBUFS;
2450 
2451 	skb = nlmsg_new(mr6_msgsize(mfc->mf6c_parent >= MAXMIFS, mrt->maxvif),
2452 			GFP_ATOMIC);
2453 	if (!skb)
2454 		goto errout;
2455 
2456 	err = ip6mr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2457 	if (err < 0)
2458 		goto errout;
2459 
2460 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE, NULL, GFP_ATOMIC);
2461 	return;
2462 
2463 errout:
2464 	kfree_skb(skb);
2465 	if (err < 0)
2466 		rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE, err);
2467 }
2468 
2469 static size_t mrt6msg_netlink_msgsize(size_t payloadlen)
2470 {
2471 	size_t len =
2472 		NLMSG_ALIGN(sizeof(struct rtgenmsg))
2473 		+ nla_total_size(1)	/* IP6MRA_CREPORT_MSGTYPE */
2474 		+ nla_total_size(4)	/* IP6MRA_CREPORT_MIF_ID */
2475 					/* IP6MRA_CREPORT_SRC_ADDR */
2476 		+ nla_total_size(sizeof(struct in6_addr))
2477 					/* IP6MRA_CREPORT_DST_ADDR */
2478 		+ nla_total_size(sizeof(struct in6_addr))
2479 					/* IP6MRA_CREPORT_PKT */
2480 		+ nla_total_size(payloadlen)
2481 		;
2482 
2483 	return len;
2484 }
2485 
2486 static void mrt6msg_netlink_event(struct mr6_table *mrt, struct sk_buff *pkt)
2487 {
2488 	struct net *net = read_pnet(&mrt->net);
2489 	struct nlmsghdr *nlh;
2490 	struct rtgenmsg *rtgenm;
2491 	struct mrt6msg *msg;
2492 	struct sk_buff *skb;
2493 	struct nlattr *nla;
2494 	int payloadlen;
2495 
2496 	payloadlen = pkt->len - sizeof(struct mrt6msg);
2497 	msg = (struct mrt6msg *)skb_transport_header(pkt);
2498 
2499 	skb = nlmsg_new(mrt6msg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2500 	if (!skb)
2501 		goto errout;
2502 
2503 	nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
2504 			sizeof(struct rtgenmsg), 0);
2505 	if (!nlh)
2506 		goto errout;
2507 	rtgenm = nlmsg_data(nlh);
2508 	rtgenm->rtgen_family = RTNL_FAMILY_IP6MR;
2509 	if (nla_put_u8(skb, IP6MRA_CREPORT_MSGTYPE, msg->im6_msgtype) ||
2510 	    nla_put_u32(skb, IP6MRA_CREPORT_MIF_ID, msg->im6_mif) ||
2511 	    nla_put_in6_addr(skb, IP6MRA_CREPORT_SRC_ADDR,
2512 			     &msg->im6_src) ||
2513 	    nla_put_in6_addr(skb, IP6MRA_CREPORT_DST_ADDR,
2514 			     &msg->im6_dst))
2515 		goto nla_put_failure;
2516 
2517 	nla = nla_reserve(skb, IP6MRA_CREPORT_PKT, payloadlen);
2518 	if (!nla || skb_copy_bits(pkt, sizeof(struct mrt6msg),
2519 				  nla_data(nla), payloadlen))
2520 		goto nla_put_failure;
2521 
2522 	nlmsg_end(skb, nlh);
2523 
2524 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE_R, NULL, GFP_ATOMIC);
2525 	return;
2526 
2527 nla_put_failure:
2528 	nlmsg_cancel(skb, nlh);
2529 errout:
2530 	kfree_skb(skb);
2531 	rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE_R, -ENOBUFS);
2532 }
2533 
2534 static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2535 {
2536 	struct net *net = sock_net(skb->sk);
2537 	struct mr6_table *mrt;
2538 	struct mfc6_cache *mfc;
2539 	unsigned int t = 0, s_t;
2540 	unsigned int h = 0, s_h;
2541 	unsigned int e = 0, s_e;
2542 
2543 	s_t = cb->args[0];
2544 	s_h = cb->args[1];
2545 	s_e = cb->args[2];
2546 
2547 	read_lock(&mrt_lock);
2548 	ip6mr_for_each_table(mrt, net) {
2549 		if (t < s_t)
2550 			goto next_table;
2551 		if (t > s_t)
2552 			s_h = 0;
2553 		for (h = s_h; h < MFC6_LINES; h++) {
2554 			list_for_each_entry(mfc, &mrt->mfc6_cache_array[h], list) {
2555 				if (e < s_e)
2556 					goto next_entry;
2557 				if (ip6mr_fill_mroute(mrt, skb,
2558 						      NETLINK_CB(cb->skb).portid,
2559 						      cb->nlh->nlmsg_seq,
2560 						      mfc, RTM_NEWROUTE,
2561 						      NLM_F_MULTI) < 0)
2562 					goto done;
2563 next_entry:
2564 				e++;
2565 			}
2566 			e = s_e = 0;
2567 		}
2568 		spin_lock_bh(&mfc_unres_lock);
2569 		list_for_each_entry(mfc, &mrt->mfc6_unres_queue, list) {
2570 			if (e < s_e)
2571 				goto next_entry2;
2572 			if (ip6mr_fill_mroute(mrt, skb,
2573 					      NETLINK_CB(cb->skb).portid,
2574 					      cb->nlh->nlmsg_seq,
2575 					      mfc, RTM_NEWROUTE,
2576 					      NLM_F_MULTI) < 0) {
2577 				spin_unlock_bh(&mfc_unres_lock);
2578 				goto done;
2579 			}
2580 next_entry2:
2581 			e++;
2582 		}
2583 		spin_unlock_bh(&mfc_unres_lock);
2584 		e = s_e = 0;
2585 		s_h = 0;
2586 next_table:
2587 		t++;
2588 	}
2589 done:
2590 	read_unlock(&mrt_lock);
2591 
2592 	cb->args[2] = e;
2593 	cb->args[1] = h;
2594 	cb->args[0] = t;
2595 
2596 	return skb->len;
2597 }
2598