xref: /linux/net/ipv4/ipmr.c (revision 900897591b2bf01154db8f59f6ecf8d60e60f15e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IP multicast routing support for mrouted 3.6/3.8
4  *
5  *		(c) 1995 Alan Cox, <alan@lxorguk.ukuu.org.uk>
6  *	  Linux Consultancy and Custom Driver Development
7  *
8  *	Fixes:
9  *	Michael Chastain	:	Incorrect size of copying.
10  *	Alan Cox		:	Added the cache manager code
11  *	Alan Cox		:	Fixed the clone/copy bug and device race.
12  *	Mike McLagan		:	Routing by source
13  *	Malcolm Beattie		:	Buffer handling fixes.
14  *	Alexey Kuznetsov	:	Double buffer free and other fixes.
15  *	SVR Anand		:	Fixed several multicast bugs and problems.
16  *	Alexey Kuznetsov	:	Status, optimisations and more.
17  *	Brad Parker		:	Better behaviour on mrouted upcall
18  *					overflow.
19  *      Carlos Picoto           :       PIMv1 Support
20  *	Pavlin Ivanov Radoslavov:	PIMv2 Registers must checksum only PIM header
21  *					Relax this requirement to work with older peers.
22  */
23 
24 #include <linux/uaccess.h>
25 #include <linux/types.h>
26 #include <linux/cache.h>
27 #include <linux/capability.h>
28 #include <linux/errno.h>
29 #include <linux/mm.h>
30 #include <linux/kernel.h>
31 #include <linux/fcntl.h>
32 #include <linux/stat.h>
33 #include <linux/socket.h>
34 #include <linux/in.h>
35 #include <linux/inet.h>
36 #include <linux/netdevice.h>
37 #include <linux/inetdevice.h>
38 #include <linux/igmp.h>
39 #include <linux/proc_fs.h>
40 #include <linux/seq_file.h>
41 #include <linux/mroute.h>
42 #include <linux/init.h>
43 #include <linux/if_ether.h>
44 #include <linux/slab.h>
45 #include <net/net_namespace.h>
46 #include <net/ip.h>
47 #include <net/protocol.h>
48 #include <linux/skbuff.h>
49 #include <net/route.h>
50 #include <net/icmp.h>
51 #include <net/udp.h>
52 #include <net/raw.h>
53 #include <linux/notifier.h>
54 #include <linux/if_arp.h>
55 #include <linux/netfilter_ipv4.h>
56 #include <linux/compat.h>
57 #include <linux/export.h>
58 #include <linux/rhashtable.h>
59 #include <net/ip_tunnels.h>
60 #include <net/checksum.h>
61 #include <net/netlink.h>
62 #include <net/fib_rules.h>
63 #include <linux/netconf.h>
64 #include <net/rtnh.h>
65 
66 #include <linux/nospec.h>
67 
68 struct ipmr_rule {
69 	struct fib_rule		common;
70 };
71 
72 struct ipmr_result {
73 	struct mr_table		*mrt;
74 };
75 
76 /* Big lock, protecting vif table, mrt cache and mroute socket state.
77  * Note that the changes are semaphored via rtnl_lock.
78  */
79 
80 static DEFINE_RWLOCK(mrt_lock);
81 
82 /* Multicast router control variables */
83 
84 /* Special spinlock for queue of unresolved entries */
85 static DEFINE_SPINLOCK(mfc_unres_lock);
86 
87 /* We return to original Alan's scheme. Hash table of resolved
88  * entries is changed only in process context and protected
89  * with weak lock mrt_lock. Queue of unresolved entries is protected
90  * with strong spinlock mfc_unres_lock.
91  *
92  * In this case data path is free of exclusive locks at all.
93  */
94 
95 static struct kmem_cache *mrt_cachep __ro_after_init;
96 
97 static struct mr_table *ipmr_new_table(struct net *net, u32 id);
98 static void ipmr_free_table(struct mr_table *mrt);
99 
100 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
101 			  struct net_device *dev, struct sk_buff *skb,
102 			  struct mfc_cache *cache, int local);
103 static int ipmr_cache_report(struct mr_table *mrt,
104 			     struct sk_buff *pkt, vifi_t vifi, int assert);
105 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
106 				 int cmd);
107 static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
108 static void mroute_clean_tables(struct mr_table *mrt, int flags);
109 static void ipmr_expire_process(struct timer_list *t);
110 
111 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
112 #define ipmr_for_each_table(mrt, net)					\
113 	list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list,	\
114 				lockdep_rtnl_is_held() ||		\
115 				list_empty(&net->ipv4.mr_tables))
116 
117 static struct mr_table *ipmr_mr_table_iter(struct net *net,
118 					   struct mr_table *mrt)
119 {
120 	struct mr_table *ret;
121 
122 	if (!mrt)
123 		ret = list_entry_rcu(net->ipv4.mr_tables.next,
124 				     struct mr_table, list);
125 	else
126 		ret = list_entry_rcu(mrt->list.next,
127 				     struct mr_table, list);
128 
129 	if (&ret->list == &net->ipv4.mr_tables)
130 		return NULL;
131 	return ret;
132 }
133 
134 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
135 {
136 	struct mr_table *mrt;
137 
138 	ipmr_for_each_table(mrt, net) {
139 		if (mrt->id == id)
140 			return mrt;
141 	}
142 	return NULL;
143 }
144 
145 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
146 			   struct mr_table **mrt)
147 {
148 	int err;
149 	struct ipmr_result res;
150 	struct fib_lookup_arg arg = {
151 		.result = &res,
152 		.flags = FIB_LOOKUP_NOREF,
153 	};
154 
155 	/* update flow if oif or iif point to device enslaved to l3mdev */
156 	l3mdev_update_flow(net, flowi4_to_flowi(flp4));
157 
158 	err = fib_rules_lookup(net->ipv4.mr_rules_ops,
159 			       flowi4_to_flowi(flp4), 0, &arg);
160 	if (err < 0)
161 		return err;
162 	*mrt = res.mrt;
163 	return 0;
164 }
165 
166 static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
167 			    int flags, struct fib_lookup_arg *arg)
168 {
169 	struct ipmr_result *res = arg->result;
170 	struct mr_table *mrt;
171 
172 	switch (rule->action) {
173 	case FR_ACT_TO_TBL:
174 		break;
175 	case FR_ACT_UNREACHABLE:
176 		return -ENETUNREACH;
177 	case FR_ACT_PROHIBIT:
178 		return -EACCES;
179 	case FR_ACT_BLACKHOLE:
180 	default:
181 		return -EINVAL;
182 	}
183 
184 	arg->table = fib_rule_get_table(rule, arg);
185 
186 	mrt = ipmr_get_table(rule->fr_net, arg->table);
187 	if (!mrt)
188 		return -EAGAIN;
189 	res->mrt = mrt;
190 	return 0;
191 }
192 
193 static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
194 {
195 	return 1;
196 }
197 
198 static const struct nla_policy ipmr_rule_policy[FRA_MAX + 1] = {
199 	FRA_GENERIC_POLICY,
200 };
201 
202 static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
203 			       struct fib_rule_hdr *frh, struct nlattr **tb,
204 			       struct netlink_ext_ack *extack)
205 {
206 	return 0;
207 }
208 
209 static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
210 			     struct nlattr **tb)
211 {
212 	return 1;
213 }
214 
215 static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
216 			  struct fib_rule_hdr *frh)
217 {
218 	frh->dst_len = 0;
219 	frh->src_len = 0;
220 	frh->tos     = 0;
221 	return 0;
222 }
223 
224 static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
225 	.family		= RTNL_FAMILY_IPMR,
226 	.rule_size	= sizeof(struct ipmr_rule),
227 	.addr_size	= sizeof(u32),
228 	.action		= ipmr_rule_action,
229 	.match		= ipmr_rule_match,
230 	.configure	= ipmr_rule_configure,
231 	.compare	= ipmr_rule_compare,
232 	.fill		= ipmr_rule_fill,
233 	.nlgroup	= RTNLGRP_IPV4_RULE,
234 	.policy		= ipmr_rule_policy,
235 	.owner		= THIS_MODULE,
236 };
237 
238 static int __net_init ipmr_rules_init(struct net *net)
239 {
240 	struct fib_rules_ops *ops;
241 	struct mr_table *mrt;
242 	int err;
243 
244 	ops = fib_rules_register(&ipmr_rules_ops_template, net);
245 	if (IS_ERR(ops))
246 		return PTR_ERR(ops);
247 
248 	INIT_LIST_HEAD(&net->ipv4.mr_tables);
249 
250 	mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
251 	if (IS_ERR(mrt)) {
252 		err = PTR_ERR(mrt);
253 		goto err1;
254 	}
255 
256 	err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
257 	if (err < 0)
258 		goto err2;
259 
260 	net->ipv4.mr_rules_ops = ops;
261 	return 0;
262 
263 err2:
264 	ipmr_free_table(mrt);
265 err1:
266 	fib_rules_unregister(ops);
267 	return err;
268 }
269 
270 static void __net_exit ipmr_rules_exit(struct net *net)
271 {
272 	struct mr_table *mrt, *next;
273 
274 	rtnl_lock();
275 	list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
276 		list_del(&mrt->list);
277 		ipmr_free_table(mrt);
278 	}
279 	fib_rules_unregister(net->ipv4.mr_rules_ops);
280 	rtnl_unlock();
281 }
282 
283 static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
284 			   struct netlink_ext_ack *extack)
285 {
286 	return fib_rules_dump(net, nb, RTNL_FAMILY_IPMR, extack);
287 }
288 
289 static unsigned int ipmr_rules_seq_read(struct net *net)
290 {
291 	return fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
292 }
293 
294 bool ipmr_rule_default(const struct fib_rule *rule)
295 {
296 	return fib_rule_matchall(rule) && rule->table == RT_TABLE_DEFAULT;
297 }
298 EXPORT_SYMBOL(ipmr_rule_default);
299 #else
300 #define ipmr_for_each_table(mrt, net) \
301 	for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
302 
303 static struct mr_table *ipmr_mr_table_iter(struct net *net,
304 					   struct mr_table *mrt)
305 {
306 	if (!mrt)
307 		return net->ipv4.mrt;
308 	return NULL;
309 }
310 
311 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
312 {
313 	return net->ipv4.mrt;
314 }
315 
316 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
317 			   struct mr_table **mrt)
318 {
319 	*mrt = net->ipv4.mrt;
320 	return 0;
321 }
322 
323 static int __net_init ipmr_rules_init(struct net *net)
324 {
325 	struct mr_table *mrt;
326 
327 	mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
328 	if (IS_ERR(mrt))
329 		return PTR_ERR(mrt);
330 	net->ipv4.mrt = mrt;
331 	return 0;
332 }
333 
334 static void __net_exit ipmr_rules_exit(struct net *net)
335 {
336 	rtnl_lock();
337 	ipmr_free_table(net->ipv4.mrt);
338 	net->ipv4.mrt = NULL;
339 	rtnl_unlock();
340 }
341 
342 static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
343 			   struct netlink_ext_ack *extack)
344 {
345 	return 0;
346 }
347 
348 static unsigned int ipmr_rules_seq_read(struct net *net)
349 {
350 	return 0;
351 }
352 
353 bool ipmr_rule_default(const struct fib_rule *rule)
354 {
355 	return true;
356 }
357 EXPORT_SYMBOL(ipmr_rule_default);
358 #endif
359 
360 static inline int ipmr_hash_cmp(struct rhashtable_compare_arg *arg,
361 				const void *ptr)
362 {
363 	const struct mfc_cache_cmp_arg *cmparg = arg->key;
364 	struct mfc_cache *c = (struct mfc_cache *)ptr;
365 
366 	return cmparg->mfc_mcastgrp != c->mfc_mcastgrp ||
367 	       cmparg->mfc_origin != c->mfc_origin;
368 }
369 
370 static const struct rhashtable_params ipmr_rht_params = {
371 	.head_offset = offsetof(struct mr_mfc, mnode),
372 	.key_offset = offsetof(struct mfc_cache, cmparg),
373 	.key_len = sizeof(struct mfc_cache_cmp_arg),
374 	.nelem_hint = 3,
375 	.obj_cmpfn = ipmr_hash_cmp,
376 	.automatic_shrinking = true,
377 };
378 
379 static void ipmr_new_table_set(struct mr_table *mrt,
380 			       struct net *net)
381 {
382 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
383 	list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
384 #endif
385 }
386 
387 static struct mfc_cache_cmp_arg ipmr_mr_table_ops_cmparg_any = {
388 	.mfc_mcastgrp = htonl(INADDR_ANY),
389 	.mfc_origin = htonl(INADDR_ANY),
390 };
391 
392 static struct mr_table_ops ipmr_mr_table_ops = {
393 	.rht_params = &ipmr_rht_params,
394 	.cmparg_any = &ipmr_mr_table_ops_cmparg_any,
395 };
396 
397 static struct mr_table *ipmr_new_table(struct net *net, u32 id)
398 {
399 	struct mr_table *mrt;
400 
401 	/* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) */
402 	if (id != RT_TABLE_DEFAULT && id >= 1000000000)
403 		return ERR_PTR(-EINVAL);
404 
405 	mrt = ipmr_get_table(net, id);
406 	if (mrt)
407 		return mrt;
408 
409 	return mr_table_alloc(net, id, &ipmr_mr_table_ops,
410 			      ipmr_expire_process, ipmr_new_table_set);
411 }
412 
413 static void ipmr_free_table(struct mr_table *mrt)
414 {
415 	del_timer_sync(&mrt->ipmr_expire_timer);
416 	mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC |
417 				 MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC);
418 	rhltable_destroy(&mrt->mfc_hash);
419 	kfree(mrt);
420 }
421 
422 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
423 
424 static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
425 {
426 	struct net *net = dev_net(dev);
427 
428 	dev_close(dev);
429 
430 	dev = __dev_get_by_name(net, "tunl0");
431 	if (dev) {
432 		const struct net_device_ops *ops = dev->netdev_ops;
433 		struct ifreq ifr;
434 		struct ip_tunnel_parm p;
435 
436 		memset(&p, 0, sizeof(p));
437 		p.iph.daddr = v->vifc_rmt_addr.s_addr;
438 		p.iph.saddr = v->vifc_lcl_addr.s_addr;
439 		p.iph.version = 4;
440 		p.iph.ihl = 5;
441 		p.iph.protocol = IPPROTO_IPIP;
442 		sprintf(p.name, "dvmrp%d", v->vifc_vifi);
443 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
444 
445 		if (ops->ndo_do_ioctl) {
446 			mm_segment_t oldfs = get_fs();
447 
448 			set_fs(KERNEL_DS);
449 			ops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
450 			set_fs(oldfs);
451 		}
452 	}
453 }
454 
455 /* Initialize ipmr pimreg/tunnel in_device */
456 static bool ipmr_init_vif_indev(const struct net_device *dev)
457 {
458 	struct in_device *in_dev;
459 
460 	ASSERT_RTNL();
461 
462 	in_dev = __in_dev_get_rtnl(dev);
463 	if (!in_dev)
464 		return false;
465 	ipv4_devconf_setall(in_dev);
466 	neigh_parms_data_state_setall(in_dev->arp_parms);
467 	IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
468 
469 	return true;
470 }
471 
472 static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
473 {
474 	struct net_device  *dev;
475 
476 	dev = __dev_get_by_name(net, "tunl0");
477 
478 	if (dev) {
479 		const struct net_device_ops *ops = dev->netdev_ops;
480 		int err;
481 		struct ifreq ifr;
482 		struct ip_tunnel_parm p;
483 
484 		memset(&p, 0, sizeof(p));
485 		p.iph.daddr = v->vifc_rmt_addr.s_addr;
486 		p.iph.saddr = v->vifc_lcl_addr.s_addr;
487 		p.iph.version = 4;
488 		p.iph.ihl = 5;
489 		p.iph.protocol = IPPROTO_IPIP;
490 		sprintf(p.name, "dvmrp%d", v->vifc_vifi);
491 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
492 
493 		if (ops->ndo_do_ioctl) {
494 			mm_segment_t oldfs = get_fs();
495 
496 			set_fs(KERNEL_DS);
497 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
498 			set_fs(oldfs);
499 		} else {
500 			err = -EOPNOTSUPP;
501 		}
502 		dev = NULL;
503 
504 		if (err == 0 &&
505 		    (dev = __dev_get_by_name(net, p.name)) != NULL) {
506 			dev->flags |= IFF_MULTICAST;
507 			if (!ipmr_init_vif_indev(dev))
508 				goto failure;
509 			if (dev_open(dev, NULL))
510 				goto failure;
511 			dev_hold(dev);
512 		}
513 	}
514 	return dev;
515 
516 failure:
517 	unregister_netdevice(dev);
518 	return NULL;
519 }
520 
521 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
522 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
523 {
524 	struct net *net = dev_net(dev);
525 	struct mr_table *mrt;
526 	struct flowi4 fl4 = {
527 		.flowi4_oif	= dev->ifindex,
528 		.flowi4_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
529 		.flowi4_mark	= skb->mark,
530 	};
531 	int err;
532 
533 	err = ipmr_fib_lookup(net, &fl4, &mrt);
534 	if (err < 0) {
535 		kfree_skb(skb);
536 		return err;
537 	}
538 
539 	read_lock(&mrt_lock);
540 	dev->stats.tx_bytes += skb->len;
541 	dev->stats.tx_packets++;
542 	ipmr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, IGMPMSG_WHOLEPKT);
543 	read_unlock(&mrt_lock);
544 	kfree_skb(skb);
545 	return NETDEV_TX_OK;
546 }
547 
548 static int reg_vif_get_iflink(const struct net_device *dev)
549 {
550 	return 0;
551 }
552 
553 static const struct net_device_ops reg_vif_netdev_ops = {
554 	.ndo_start_xmit	= reg_vif_xmit,
555 	.ndo_get_iflink = reg_vif_get_iflink,
556 };
557 
558 static void reg_vif_setup(struct net_device *dev)
559 {
560 	dev->type		= ARPHRD_PIMREG;
561 	dev->mtu		= ETH_DATA_LEN - sizeof(struct iphdr) - 8;
562 	dev->flags		= IFF_NOARP;
563 	dev->netdev_ops		= &reg_vif_netdev_ops;
564 	dev->needs_free_netdev	= true;
565 	dev->features		|= NETIF_F_NETNS_LOCAL;
566 }
567 
568 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
569 {
570 	struct net_device *dev;
571 	char name[IFNAMSIZ];
572 
573 	if (mrt->id == RT_TABLE_DEFAULT)
574 		sprintf(name, "pimreg");
575 	else
576 		sprintf(name, "pimreg%u", mrt->id);
577 
578 	dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
579 
580 	if (!dev)
581 		return NULL;
582 
583 	dev_net_set(dev, net);
584 
585 	if (register_netdevice(dev)) {
586 		free_netdev(dev);
587 		return NULL;
588 	}
589 
590 	if (!ipmr_init_vif_indev(dev))
591 		goto failure;
592 	if (dev_open(dev, NULL))
593 		goto failure;
594 
595 	dev_hold(dev);
596 
597 	return dev;
598 
599 failure:
600 	unregister_netdevice(dev);
601 	return NULL;
602 }
603 
604 /* called with rcu_read_lock() */
605 static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
606 		     unsigned int pimlen)
607 {
608 	struct net_device *reg_dev = NULL;
609 	struct iphdr *encap;
610 
611 	encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
612 	/* Check that:
613 	 * a. packet is really sent to a multicast group
614 	 * b. packet is not a NULL-REGISTER
615 	 * c. packet is not truncated
616 	 */
617 	if (!ipv4_is_multicast(encap->daddr) ||
618 	    encap->tot_len == 0 ||
619 	    ntohs(encap->tot_len) + pimlen > skb->len)
620 		return 1;
621 
622 	read_lock(&mrt_lock);
623 	if (mrt->mroute_reg_vif_num >= 0)
624 		reg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
625 	read_unlock(&mrt_lock);
626 
627 	if (!reg_dev)
628 		return 1;
629 
630 	skb->mac_header = skb->network_header;
631 	skb_pull(skb, (u8 *)encap - skb->data);
632 	skb_reset_network_header(skb);
633 	skb->protocol = htons(ETH_P_IP);
634 	skb->ip_summed = CHECKSUM_NONE;
635 
636 	skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
637 
638 	netif_rx(skb);
639 
640 	return NET_RX_SUCCESS;
641 }
642 #else
643 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
644 {
645 	return NULL;
646 }
647 #endif
648 
649 static int call_ipmr_vif_entry_notifiers(struct net *net,
650 					 enum fib_event_type event_type,
651 					 struct vif_device *vif,
652 					 vifi_t vif_index, u32 tb_id)
653 {
654 	return mr_call_vif_notifiers(net, RTNL_FAMILY_IPMR, event_type,
655 				     vif, vif_index, tb_id,
656 				     &net->ipv4.ipmr_seq);
657 }
658 
659 static int call_ipmr_mfc_entry_notifiers(struct net *net,
660 					 enum fib_event_type event_type,
661 					 struct mfc_cache *mfc, u32 tb_id)
662 {
663 	return mr_call_mfc_notifiers(net, RTNL_FAMILY_IPMR, event_type,
664 				     &mfc->_c, tb_id, &net->ipv4.ipmr_seq);
665 }
666 
667 /**
668  *	vif_delete - Delete a VIF entry
669  *	@notify: Set to 1, if the caller is a notifier_call
670  */
671 static int vif_delete(struct mr_table *mrt, int vifi, int notify,
672 		      struct list_head *head)
673 {
674 	struct net *net = read_pnet(&mrt->net);
675 	struct vif_device *v;
676 	struct net_device *dev;
677 	struct in_device *in_dev;
678 
679 	if (vifi < 0 || vifi >= mrt->maxvif)
680 		return -EADDRNOTAVAIL;
681 
682 	v = &mrt->vif_table[vifi];
683 
684 	if (VIF_EXISTS(mrt, vifi))
685 		call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_DEL, v, vifi,
686 					      mrt->id);
687 
688 	write_lock_bh(&mrt_lock);
689 	dev = v->dev;
690 	v->dev = NULL;
691 
692 	if (!dev) {
693 		write_unlock_bh(&mrt_lock);
694 		return -EADDRNOTAVAIL;
695 	}
696 
697 	if (vifi == mrt->mroute_reg_vif_num)
698 		mrt->mroute_reg_vif_num = -1;
699 
700 	if (vifi + 1 == mrt->maxvif) {
701 		int tmp;
702 
703 		for (tmp = vifi - 1; tmp >= 0; tmp--) {
704 			if (VIF_EXISTS(mrt, tmp))
705 				break;
706 		}
707 		mrt->maxvif = tmp+1;
708 	}
709 
710 	write_unlock_bh(&mrt_lock);
711 
712 	dev_set_allmulti(dev, -1);
713 
714 	in_dev = __in_dev_get_rtnl(dev);
715 	if (in_dev) {
716 		IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
717 		inet_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
718 					    NETCONFA_MC_FORWARDING,
719 					    dev->ifindex, &in_dev->cnf);
720 		ip_rt_multicast_event(in_dev);
721 	}
722 
723 	if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
724 		unregister_netdevice_queue(dev, head);
725 
726 	dev_put(dev);
727 	return 0;
728 }
729 
730 static void ipmr_cache_free_rcu(struct rcu_head *head)
731 {
732 	struct mr_mfc *c = container_of(head, struct mr_mfc, rcu);
733 
734 	kmem_cache_free(mrt_cachep, (struct mfc_cache *)c);
735 }
736 
737 static void ipmr_cache_free(struct mfc_cache *c)
738 {
739 	call_rcu(&c->_c.rcu, ipmr_cache_free_rcu);
740 }
741 
742 /* Destroy an unresolved cache entry, killing queued skbs
743  * and reporting error to netlink readers.
744  */
745 static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
746 {
747 	struct net *net = read_pnet(&mrt->net);
748 	struct sk_buff *skb;
749 	struct nlmsgerr *e;
750 
751 	atomic_dec(&mrt->cache_resolve_queue_len);
752 
753 	while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved))) {
754 		if (ip_hdr(skb)->version == 0) {
755 			struct nlmsghdr *nlh = skb_pull(skb,
756 							sizeof(struct iphdr));
757 			nlh->nlmsg_type = NLMSG_ERROR;
758 			nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
759 			skb_trim(skb, nlh->nlmsg_len);
760 			e = nlmsg_data(nlh);
761 			e->error = -ETIMEDOUT;
762 			memset(&e->msg, 0, sizeof(e->msg));
763 
764 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
765 		} else {
766 			kfree_skb(skb);
767 		}
768 	}
769 
770 	ipmr_cache_free(c);
771 }
772 
773 /* Timer process for the unresolved queue. */
774 static void ipmr_expire_process(struct timer_list *t)
775 {
776 	struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
777 	struct mr_mfc *c, *next;
778 	unsigned long expires;
779 	unsigned long now;
780 
781 	if (!spin_trylock(&mfc_unres_lock)) {
782 		mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10);
783 		return;
784 	}
785 
786 	if (list_empty(&mrt->mfc_unres_queue))
787 		goto out;
788 
789 	now = jiffies;
790 	expires = 10*HZ;
791 
792 	list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
793 		if (time_after(c->mfc_un.unres.expires, now)) {
794 			unsigned long interval = c->mfc_un.unres.expires - now;
795 			if (interval < expires)
796 				expires = interval;
797 			continue;
798 		}
799 
800 		list_del(&c->list);
801 		mroute_netlink_event(mrt, (struct mfc_cache *)c, RTM_DELROUTE);
802 		ipmr_destroy_unres(mrt, (struct mfc_cache *)c);
803 	}
804 
805 	if (!list_empty(&mrt->mfc_unres_queue))
806 		mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
807 
808 out:
809 	spin_unlock(&mfc_unres_lock);
810 }
811 
812 /* Fill oifs list. It is called under write locked mrt_lock. */
813 static void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
814 				   unsigned char *ttls)
815 {
816 	int vifi;
817 
818 	cache->mfc_un.res.minvif = MAXVIFS;
819 	cache->mfc_un.res.maxvif = 0;
820 	memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
821 
822 	for (vifi = 0; vifi < mrt->maxvif; vifi++) {
823 		if (VIF_EXISTS(mrt, vifi) &&
824 		    ttls[vifi] && ttls[vifi] < 255) {
825 			cache->mfc_un.res.ttls[vifi] = ttls[vifi];
826 			if (cache->mfc_un.res.minvif > vifi)
827 				cache->mfc_un.res.minvif = vifi;
828 			if (cache->mfc_un.res.maxvif <= vifi)
829 				cache->mfc_un.res.maxvif = vifi + 1;
830 		}
831 	}
832 	cache->mfc_un.res.lastuse = jiffies;
833 }
834 
835 static int vif_add(struct net *net, struct mr_table *mrt,
836 		   struct vifctl *vifc, int mrtsock)
837 {
838 	struct netdev_phys_item_id ppid = { };
839 	int vifi = vifc->vifc_vifi;
840 	struct vif_device *v = &mrt->vif_table[vifi];
841 	struct net_device *dev;
842 	struct in_device *in_dev;
843 	int err;
844 
845 	/* Is vif busy ? */
846 	if (VIF_EXISTS(mrt, vifi))
847 		return -EADDRINUSE;
848 
849 	switch (vifc->vifc_flags) {
850 	case VIFF_REGISTER:
851 		if (!ipmr_pimsm_enabled())
852 			return -EINVAL;
853 		/* Special Purpose VIF in PIM
854 		 * All the packets will be sent to the daemon
855 		 */
856 		if (mrt->mroute_reg_vif_num >= 0)
857 			return -EADDRINUSE;
858 		dev = ipmr_reg_vif(net, mrt);
859 		if (!dev)
860 			return -ENOBUFS;
861 		err = dev_set_allmulti(dev, 1);
862 		if (err) {
863 			unregister_netdevice(dev);
864 			dev_put(dev);
865 			return err;
866 		}
867 		break;
868 	case VIFF_TUNNEL:
869 		dev = ipmr_new_tunnel(net, vifc);
870 		if (!dev)
871 			return -ENOBUFS;
872 		err = dev_set_allmulti(dev, 1);
873 		if (err) {
874 			ipmr_del_tunnel(dev, vifc);
875 			dev_put(dev);
876 			return err;
877 		}
878 		break;
879 	case VIFF_USE_IFINDEX:
880 	case 0:
881 		if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
882 			dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
883 			if (dev && !__in_dev_get_rtnl(dev)) {
884 				dev_put(dev);
885 				return -EADDRNOTAVAIL;
886 			}
887 		} else {
888 			dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
889 		}
890 		if (!dev)
891 			return -EADDRNOTAVAIL;
892 		err = dev_set_allmulti(dev, 1);
893 		if (err) {
894 			dev_put(dev);
895 			return err;
896 		}
897 		break;
898 	default:
899 		return -EINVAL;
900 	}
901 
902 	in_dev = __in_dev_get_rtnl(dev);
903 	if (!in_dev) {
904 		dev_put(dev);
905 		return -EADDRNOTAVAIL;
906 	}
907 	IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
908 	inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING,
909 				    dev->ifindex, &in_dev->cnf);
910 	ip_rt_multicast_event(in_dev);
911 
912 	/* Fill in the VIF structures */
913 	vif_device_init(v, dev, vifc->vifc_rate_limit,
914 			vifc->vifc_threshold,
915 			vifc->vifc_flags | (!mrtsock ? VIFF_STATIC : 0),
916 			(VIFF_TUNNEL | VIFF_REGISTER));
917 
918 	err = dev_get_port_parent_id(dev, &ppid, true);
919 	if (err == 0) {
920 		memcpy(v->dev_parent_id.id, ppid.id, ppid.id_len);
921 		v->dev_parent_id.id_len = ppid.id_len;
922 	} else {
923 		v->dev_parent_id.id_len = 0;
924 	}
925 
926 	v->local = vifc->vifc_lcl_addr.s_addr;
927 	v->remote = vifc->vifc_rmt_addr.s_addr;
928 
929 	/* And finish update writing critical data */
930 	write_lock_bh(&mrt_lock);
931 	v->dev = dev;
932 	if (v->flags & VIFF_REGISTER)
933 		mrt->mroute_reg_vif_num = vifi;
934 	if (vifi+1 > mrt->maxvif)
935 		mrt->maxvif = vifi+1;
936 	write_unlock_bh(&mrt_lock);
937 	call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD, v, vifi, mrt->id);
938 	return 0;
939 }
940 
941 /* called with rcu_read_lock() */
942 static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
943 					 __be32 origin,
944 					 __be32 mcastgrp)
945 {
946 	struct mfc_cache_cmp_arg arg = {
947 			.mfc_mcastgrp = mcastgrp,
948 			.mfc_origin = origin
949 	};
950 
951 	return mr_mfc_find(mrt, &arg);
952 }
953 
954 /* Look for a (*,G) entry */
955 static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
956 					     __be32 mcastgrp, int vifi)
957 {
958 	struct mfc_cache_cmp_arg arg = {
959 			.mfc_mcastgrp = mcastgrp,
960 			.mfc_origin = htonl(INADDR_ANY)
961 	};
962 
963 	if (mcastgrp == htonl(INADDR_ANY))
964 		return mr_mfc_find_any_parent(mrt, vifi);
965 	return mr_mfc_find_any(mrt, vifi, &arg);
966 }
967 
968 /* Look for a (S,G,iif) entry if parent != -1 */
969 static struct mfc_cache *ipmr_cache_find_parent(struct mr_table *mrt,
970 						__be32 origin, __be32 mcastgrp,
971 						int parent)
972 {
973 	struct mfc_cache_cmp_arg arg = {
974 			.mfc_mcastgrp = mcastgrp,
975 			.mfc_origin = origin,
976 	};
977 
978 	return mr_mfc_find_parent(mrt, &arg, parent);
979 }
980 
981 /* Allocate a multicast cache entry */
982 static struct mfc_cache *ipmr_cache_alloc(void)
983 {
984 	struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
985 
986 	if (c) {
987 		c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
988 		c->_c.mfc_un.res.minvif = MAXVIFS;
989 		c->_c.free = ipmr_cache_free_rcu;
990 		refcount_set(&c->_c.mfc_un.res.refcount, 1);
991 	}
992 	return c;
993 }
994 
995 static struct mfc_cache *ipmr_cache_alloc_unres(void)
996 {
997 	struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
998 
999 	if (c) {
1000 		skb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
1001 		c->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
1002 	}
1003 	return c;
1004 }
1005 
1006 /* A cache entry has gone into a resolved state from queued */
1007 static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
1008 			       struct mfc_cache *uc, struct mfc_cache *c)
1009 {
1010 	struct sk_buff *skb;
1011 	struct nlmsgerr *e;
1012 
1013 	/* Play the pending entries through our router */
1014 	while ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
1015 		if (ip_hdr(skb)->version == 0) {
1016 			struct nlmsghdr *nlh = skb_pull(skb,
1017 							sizeof(struct iphdr));
1018 
1019 			if (mr_fill_mroute(mrt, skb, &c->_c,
1020 					   nlmsg_data(nlh)) > 0) {
1021 				nlh->nlmsg_len = skb_tail_pointer(skb) -
1022 						 (u8 *)nlh;
1023 			} else {
1024 				nlh->nlmsg_type = NLMSG_ERROR;
1025 				nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
1026 				skb_trim(skb, nlh->nlmsg_len);
1027 				e = nlmsg_data(nlh);
1028 				e->error = -EMSGSIZE;
1029 				memset(&e->msg, 0, sizeof(e->msg));
1030 			}
1031 
1032 			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
1033 		} else {
1034 			ip_mr_forward(net, mrt, skb->dev, skb, c, 0);
1035 		}
1036 	}
1037 }
1038 
1039 /* Bounce a cache query up to mrouted and netlink.
1040  *
1041  * Called under mrt_lock.
1042  */
1043 static int ipmr_cache_report(struct mr_table *mrt,
1044 			     struct sk_buff *pkt, vifi_t vifi, int assert)
1045 {
1046 	const int ihl = ip_hdrlen(pkt);
1047 	struct sock *mroute_sk;
1048 	struct igmphdr *igmp;
1049 	struct igmpmsg *msg;
1050 	struct sk_buff *skb;
1051 	int ret;
1052 
1053 	if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE)
1054 		skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
1055 	else
1056 		skb = alloc_skb(128, GFP_ATOMIC);
1057 
1058 	if (!skb)
1059 		return -ENOBUFS;
1060 
1061 	if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) {
1062 		/* Ugly, but we have no choice with this interface.
1063 		 * Duplicate old header, fix ihl, length etc.
1064 		 * And all this only to mangle msg->im_msgtype and
1065 		 * to set msg->im_mbz to "mbz" :-)
1066 		 */
1067 		skb_push(skb, sizeof(struct iphdr));
1068 		skb_reset_network_header(skb);
1069 		skb_reset_transport_header(skb);
1070 		msg = (struct igmpmsg *)skb_network_header(skb);
1071 		memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
1072 		msg->im_msgtype = assert;
1073 		msg->im_mbz = 0;
1074 		if (assert == IGMPMSG_WRVIFWHOLE)
1075 			msg->im_vif = vifi;
1076 		else
1077 			msg->im_vif = mrt->mroute_reg_vif_num;
1078 		ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
1079 		ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
1080 					     sizeof(struct iphdr));
1081 	} else {
1082 		/* Copy the IP header */
1083 		skb_set_network_header(skb, skb->len);
1084 		skb_put(skb, ihl);
1085 		skb_copy_to_linear_data(skb, pkt->data, ihl);
1086 		/* Flag to the kernel this is a route add */
1087 		ip_hdr(skb)->protocol = 0;
1088 		msg = (struct igmpmsg *)skb_network_header(skb);
1089 		msg->im_vif = vifi;
1090 		skb_dst_set(skb, dst_clone(skb_dst(pkt)));
1091 		/* Add our header */
1092 		igmp = skb_put(skb, sizeof(struct igmphdr));
1093 		igmp->type = assert;
1094 		msg->im_msgtype = assert;
1095 		igmp->code = 0;
1096 		ip_hdr(skb)->tot_len = htons(skb->len);	/* Fix the length */
1097 		skb->transport_header = skb->network_header;
1098 	}
1099 
1100 	rcu_read_lock();
1101 	mroute_sk = rcu_dereference(mrt->mroute_sk);
1102 	if (!mroute_sk) {
1103 		rcu_read_unlock();
1104 		kfree_skb(skb);
1105 		return -EINVAL;
1106 	}
1107 
1108 	igmpmsg_netlink_event(mrt, skb);
1109 
1110 	/* Deliver to mrouted */
1111 	ret = sock_queue_rcv_skb(mroute_sk, skb);
1112 	rcu_read_unlock();
1113 	if (ret < 0) {
1114 		net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1115 		kfree_skb(skb);
1116 	}
1117 
1118 	return ret;
1119 }
1120 
1121 /* Queue a packet for resolution. It gets locked cache entry! */
1122 static int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi,
1123 				 struct sk_buff *skb, struct net_device *dev)
1124 {
1125 	const struct iphdr *iph = ip_hdr(skb);
1126 	struct mfc_cache *c;
1127 	bool found = false;
1128 	int err;
1129 
1130 	spin_lock_bh(&mfc_unres_lock);
1131 	list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
1132 		if (c->mfc_mcastgrp == iph->daddr &&
1133 		    c->mfc_origin == iph->saddr) {
1134 			found = true;
1135 			break;
1136 		}
1137 	}
1138 
1139 	if (!found) {
1140 		/* Create a new entry if allowable */
1141 		c = ipmr_cache_alloc_unres();
1142 		if (!c) {
1143 			spin_unlock_bh(&mfc_unres_lock);
1144 
1145 			kfree_skb(skb);
1146 			return -ENOBUFS;
1147 		}
1148 
1149 		/* Fill in the new cache entry */
1150 		c->_c.mfc_parent = -1;
1151 		c->mfc_origin	= iph->saddr;
1152 		c->mfc_mcastgrp	= iph->daddr;
1153 
1154 		/* Reflect first query at mrouted. */
1155 		err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1156 
1157 		if (err < 0) {
1158 			/* If the report failed throw the cache entry
1159 			   out - Brad Parker
1160 			 */
1161 			spin_unlock_bh(&mfc_unres_lock);
1162 
1163 			ipmr_cache_free(c);
1164 			kfree_skb(skb);
1165 			return err;
1166 		}
1167 
1168 		atomic_inc(&mrt->cache_resolve_queue_len);
1169 		list_add(&c->_c.list, &mrt->mfc_unres_queue);
1170 		mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1171 
1172 		if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1173 			mod_timer(&mrt->ipmr_expire_timer,
1174 				  c->_c.mfc_un.unres.expires);
1175 	}
1176 
1177 	/* See if we can append the packet */
1178 	if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
1179 		kfree_skb(skb);
1180 		err = -ENOBUFS;
1181 	} else {
1182 		if (dev) {
1183 			skb->dev = dev;
1184 			skb->skb_iif = dev->ifindex;
1185 		}
1186 		skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
1187 		err = 0;
1188 	}
1189 
1190 	spin_unlock_bh(&mfc_unres_lock);
1191 	return err;
1192 }
1193 
1194 /* MFC cache manipulation by user space mroute daemon */
1195 
1196 static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1197 {
1198 	struct net *net = read_pnet(&mrt->net);
1199 	struct mfc_cache *c;
1200 
1201 	/* The entries are added/deleted only under RTNL */
1202 	rcu_read_lock();
1203 	c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1204 				   mfc->mfcc_mcastgrp.s_addr, parent);
1205 	rcu_read_unlock();
1206 	if (!c)
1207 		return -ENOENT;
1208 	rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ipmr_rht_params);
1209 	list_del_rcu(&c->_c.list);
1210 	call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id);
1211 	mroute_netlink_event(mrt, c, RTM_DELROUTE);
1212 	mr_cache_put(&c->_c);
1213 
1214 	return 0;
1215 }
1216 
1217 static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1218 			struct mfcctl *mfc, int mrtsock, int parent)
1219 {
1220 	struct mfc_cache *uc, *c;
1221 	struct mr_mfc *_uc;
1222 	bool found;
1223 	int ret;
1224 
1225 	if (mfc->mfcc_parent >= MAXVIFS)
1226 		return -ENFILE;
1227 
1228 	/* The entries are added/deleted only under RTNL */
1229 	rcu_read_lock();
1230 	c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1231 				   mfc->mfcc_mcastgrp.s_addr, parent);
1232 	rcu_read_unlock();
1233 	if (c) {
1234 		write_lock_bh(&mrt_lock);
1235 		c->_c.mfc_parent = mfc->mfcc_parent;
1236 		ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1237 		if (!mrtsock)
1238 			c->_c.mfc_flags |= MFC_STATIC;
1239 		write_unlock_bh(&mrt_lock);
1240 		call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c,
1241 					      mrt->id);
1242 		mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1243 		return 0;
1244 	}
1245 
1246 	if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1247 	    !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1248 		return -EINVAL;
1249 
1250 	c = ipmr_cache_alloc();
1251 	if (!c)
1252 		return -ENOMEM;
1253 
1254 	c->mfc_origin = mfc->mfcc_origin.s_addr;
1255 	c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1256 	c->_c.mfc_parent = mfc->mfcc_parent;
1257 	ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1258 	if (!mrtsock)
1259 		c->_c.mfc_flags |= MFC_STATIC;
1260 
1261 	ret = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
1262 				  ipmr_rht_params);
1263 	if (ret) {
1264 		pr_err("ipmr: rhtable insert error %d\n", ret);
1265 		ipmr_cache_free(c);
1266 		return ret;
1267 	}
1268 	list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
1269 	/* Check to see if we resolved a queued list. If so we
1270 	 * need to send on the frames and tidy up.
1271 	 */
1272 	found = false;
1273 	spin_lock_bh(&mfc_unres_lock);
1274 	list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
1275 		uc = (struct mfc_cache *)_uc;
1276 		if (uc->mfc_origin == c->mfc_origin &&
1277 		    uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1278 			list_del(&_uc->list);
1279 			atomic_dec(&mrt->cache_resolve_queue_len);
1280 			found = true;
1281 			break;
1282 		}
1283 	}
1284 	if (list_empty(&mrt->mfc_unres_queue))
1285 		del_timer(&mrt->ipmr_expire_timer);
1286 	spin_unlock_bh(&mfc_unres_lock);
1287 
1288 	if (found) {
1289 		ipmr_cache_resolve(net, mrt, uc, c);
1290 		ipmr_cache_free(uc);
1291 	}
1292 	call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, c, mrt->id);
1293 	mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1294 	return 0;
1295 }
1296 
1297 /* Close the multicast socket, and clear the vif tables etc */
1298 static void mroute_clean_tables(struct mr_table *mrt, int flags)
1299 {
1300 	struct net *net = read_pnet(&mrt->net);
1301 	struct mr_mfc *c, *tmp;
1302 	struct mfc_cache *cache;
1303 	LIST_HEAD(list);
1304 	int i;
1305 
1306 	/* Shut down all active vif entries */
1307 	if (flags & (MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC)) {
1308 		for (i = 0; i < mrt->maxvif; i++) {
1309 			if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
1310 			     !(flags & MRT_FLUSH_VIFS_STATIC)) ||
1311 			    (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT_FLUSH_VIFS)))
1312 				continue;
1313 			vif_delete(mrt, i, 0, &list);
1314 		}
1315 		unregister_netdevice_many(&list);
1316 	}
1317 
1318 	/* Wipe the cache */
1319 	if (flags & (MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC)) {
1320 		list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
1321 			if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC_STATIC)) ||
1322 			    (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC)))
1323 				continue;
1324 			rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
1325 			list_del_rcu(&c->list);
1326 			cache = (struct mfc_cache *)c;
1327 			call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
1328 						      mrt->id);
1329 			mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1330 			mr_cache_put(c);
1331 		}
1332 	}
1333 
1334 	if (flags & MRT_FLUSH_MFC) {
1335 		if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1336 			spin_lock_bh(&mfc_unres_lock);
1337 			list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
1338 				list_del(&c->list);
1339 				cache = (struct mfc_cache *)c;
1340 				mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1341 				ipmr_destroy_unres(mrt, cache);
1342 			}
1343 			spin_unlock_bh(&mfc_unres_lock);
1344 		}
1345 	}
1346 }
1347 
1348 /* called from ip_ra_control(), before an RCU grace period,
1349  * we dont need to call synchronize_rcu() here
1350  */
1351 static void mrtsock_destruct(struct sock *sk)
1352 {
1353 	struct net *net = sock_net(sk);
1354 	struct mr_table *mrt;
1355 
1356 	rtnl_lock();
1357 	ipmr_for_each_table(mrt, net) {
1358 		if (sk == rtnl_dereference(mrt->mroute_sk)) {
1359 			IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1360 			inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1361 						    NETCONFA_MC_FORWARDING,
1362 						    NETCONFA_IFINDEX_ALL,
1363 						    net->ipv4.devconf_all);
1364 			RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1365 			mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_MFC);
1366 		}
1367 	}
1368 	rtnl_unlock();
1369 }
1370 
1371 /* Socket options and virtual interface manipulation. The whole
1372  * virtual interface system is a complete heap, but unfortunately
1373  * that's how BSD mrouted happens to think. Maybe one day with a proper
1374  * MOSPF/PIM router set up we can clean this up.
1375  */
1376 
1377 int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval,
1378 			 unsigned int optlen)
1379 {
1380 	struct net *net = sock_net(sk);
1381 	int val, ret = 0, parent = 0;
1382 	struct mr_table *mrt;
1383 	struct vifctl vif;
1384 	struct mfcctl mfc;
1385 	bool do_wrvifwhole;
1386 	u32 uval;
1387 
1388 	/* There's one exception to the lock - MRT_DONE which needs to unlock */
1389 	rtnl_lock();
1390 	if (sk->sk_type != SOCK_RAW ||
1391 	    inet_sk(sk)->inet_num != IPPROTO_IGMP) {
1392 		ret = -EOPNOTSUPP;
1393 		goto out_unlock;
1394 	}
1395 
1396 	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1397 	if (!mrt) {
1398 		ret = -ENOENT;
1399 		goto out_unlock;
1400 	}
1401 	if (optname != MRT_INIT) {
1402 		if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1403 		    !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
1404 			ret = -EACCES;
1405 			goto out_unlock;
1406 		}
1407 	}
1408 
1409 	switch (optname) {
1410 	case MRT_INIT:
1411 		if (optlen != sizeof(int)) {
1412 			ret = -EINVAL;
1413 			break;
1414 		}
1415 		if (rtnl_dereference(mrt->mroute_sk)) {
1416 			ret = -EADDRINUSE;
1417 			break;
1418 		}
1419 
1420 		ret = ip_ra_control(sk, 1, mrtsock_destruct);
1421 		if (ret == 0) {
1422 			rcu_assign_pointer(mrt->mroute_sk, sk);
1423 			IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1424 			inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1425 						    NETCONFA_MC_FORWARDING,
1426 						    NETCONFA_IFINDEX_ALL,
1427 						    net->ipv4.devconf_all);
1428 		}
1429 		break;
1430 	case MRT_DONE:
1431 		if (sk != rcu_access_pointer(mrt->mroute_sk)) {
1432 			ret = -EACCES;
1433 		} else {
1434 			/* We need to unlock here because mrtsock_destruct takes
1435 			 * care of rtnl itself and we can't change that due to
1436 			 * the IP_ROUTER_ALERT setsockopt which runs without it.
1437 			 */
1438 			rtnl_unlock();
1439 			ret = ip_ra_control(sk, 0, NULL);
1440 			goto out;
1441 		}
1442 		break;
1443 	case MRT_ADD_VIF:
1444 	case MRT_DEL_VIF:
1445 		if (optlen != sizeof(vif)) {
1446 			ret = -EINVAL;
1447 			break;
1448 		}
1449 		if (copy_from_user(&vif, optval, sizeof(vif))) {
1450 			ret = -EFAULT;
1451 			break;
1452 		}
1453 		if (vif.vifc_vifi >= MAXVIFS) {
1454 			ret = -ENFILE;
1455 			break;
1456 		}
1457 		if (optname == MRT_ADD_VIF) {
1458 			ret = vif_add(net, mrt, &vif,
1459 				      sk == rtnl_dereference(mrt->mroute_sk));
1460 		} else {
1461 			ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1462 		}
1463 		break;
1464 	/* Manipulate the forwarding caches. These live
1465 	 * in a sort of kernel/user symbiosis.
1466 	 */
1467 	case MRT_ADD_MFC:
1468 	case MRT_DEL_MFC:
1469 		parent = -1;
1470 		fallthrough;
1471 	case MRT_ADD_MFC_PROXY:
1472 	case MRT_DEL_MFC_PROXY:
1473 		if (optlen != sizeof(mfc)) {
1474 			ret = -EINVAL;
1475 			break;
1476 		}
1477 		if (copy_from_user(&mfc, optval, sizeof(mfc))) {
1478 			ret = -EFAULT;
1479 			break;
1480 		}
1481 		if (parent == 0)
1482 			parent = mfc.mfcc_parent;
1483 		if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1484 			ret = ipmr_mfc_delete(mrt, &mfc, parent);
1485 		else
1486 			ret = ipmr_mfc_add(net, mrt, &mfc,
1487 					   sk == rtnl_dereference(mrt->mroute_sk),
1488 					   parent);
1489 		break;
1490 	case MRT_FLUSH:
1491 		if (optlen != sizeof(val)) {
1492 			ret = -EINVAL;
1493 			break;
1494 		}
1495 		if (get_user(val, (int __user *)optval)) {
1496 			ret = -EFAULT;
1497 			break;
1498 		}
1499 		mroute_clean_tables(mrt, val);
1500 		break;
1501 	/* Control PIM assert. */
1502 	case MRT_ASSERT:
1503 		if (optlen != sizeof(val)) {
1504 			ret = -EINVAL;
1505 			break;
1506 		}
1507 		if (get_user(val, (int __user *)optval)) {
1508 			ret = -EFAULT;
1509 			break;
1510 		}
1511 		mrt->mroute_do_assert = val;
1512 		break;
1513 	case MRT_PIM:
1514 		if (!ipmr_pimsm_enabled()) {
1515 			ret = -ENOPROTOOPT;
1516 			break;
1517 		}
1518 		if (optlen != sizeof(val)) {
1519 			ret = -EINVAL;
1520 			break;
1521 		}
1522 		if (get_user(val, (int __user *)optval)) {
1523 			ret = -EFAULT;
1524 			break;
1525 		}
1526 
1527 		do_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE);
1528 		val = !!val;
1529 		if (val != mrt->mroute_do_pim) {
1530 			mrt->mroute_do_pim = val;
1531 			mrt->mroute_do_assert = val;
1532 			mrt->mroute_do_wrvifwhole = do_wrvifwhole;
1533 		}
1534 		break;
1535 	case MRT_TABLE:
1536 		if (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) {
1537 			ret = -ENOPROTOOPT;
1538 			break;
1539 		}
1540 		if (optlen != sizeof(uval)) {
1541 			ret = -EINVAL;
1542 			break;
1543 		}
1544 		if (get_user(uval, (u32 __user *)optval)) {
1545 			ret = -EFAULT;
1546 			break;
1547 		}
1548 
1549 		if (sk == rtnl_dereference(mrt->mroute_sk)) {
1550 			ret = -EBUSY;
1551 		} else {
1552 			mrt = ipmr_new_table(net, uval);
1553 			if (IS_ERR(mrt))
1554 				ret = PTR_ERR(mrt);
1555 			else
1556 				raw_sk(sk)->ipmr_table = uval;
1557 		}
1558 		break;
1559 	/* Spurious command, or MRT_VERSION which you cannot set. */
1560 	default:
1561 		ret = -ENOPROTOOPT;
1562 	}
1563 out_unlock:
1564 	rtnl_unlock();
1565 out:
1566 	return ret;
1567 }
1568 
1569 /* Getsock opt support for the multicast routing system. */
1570 int ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen)
1571 {
1572 	int olr;
1573 	int val;
1574 	struct net *net = sock_net(sk);
1575 	struct mr_table *mrt;
1576 
1577 	if (sk->sk_type != SOCK_RAW ||
1578 	    inet_sk(sk)->inet_num != IPPROTO_IGMP)
1579 		return -EOPNOTSUPP;
1580 
1581 	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1582 	if (!mrt)
1583 		return -ENOENT;
1584 
1585 	switch (optname) {
1586 	case MRT_VERSION:
1587 		val = 0x0305;
1588 		break;
1589 	case MRT_PIM:
1590 		if (!ipmr_pimsm_enabled())
1591 			return -ENOPROTOOPT;
1592 		val = mrt->mroute_do_pim;
1593 		break;
1594 	case MRT_ASSERT:
1595 		val = mrt->mroute_do_assert;
1596 		break;
1597 	default:
1598 		return -ENOPROTOOPT;
1599 	}
1600 
1601 	if (get_user(olr, optlen))
1602 		return -EFAULT;
1603 	olr = min_t(unsigned int, olr, sizeof(int));
1604 	if (olr < 0)
1605 		return -EINVAL;
1606 	if (put_user(olr, optlen))
1607 		return -EFAULT;
1608 	if (copy_to_user(optval, &val, olr))
1609 		return -EFAULT;
1610 	return 0;
1611 }
1612 
1613 /* The IP multicast ioctl support routines. */
1614 int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
1615 {
1616 	struct sioc_sg_req sr;
1617 	struct sioc_vif_req vr;
1618 	struct vif_device *vif;
1619 	struct mfc_cache *c;
1620 	struct net *net = sock_net(sk);
1621 	struct mr_table *mrt;
1622 
1623 	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1624 	if (!mrt)
1625 		return -ENOENT;
1626 
1627 	switch (cmd) {
1628 	case SIOCGETVIFCNT:
1629 		if (copy_from_user(&vr, arg, sizeof(vr)))
1630 			return -EFAULT;
1631 		if (vr.vifi >= mrt->maxvif)
1632 			return -EINVAL;
1633 		vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
1634 		read_lock(&mrt_lock);
1635 		vif = &mrt->vif_table[vr.vifi];
1636 		if (VIF_EXISTS(mrt, vr.vifi)) {
1637 			vr.icount = vif->pkt_in;
1638 			vr.ocount = vif->pkt_out;
1639 			vr.ibytes = vif->bytes_in;
1640 			vr.obytes = vif->bytes_out;
1641 			read_unlock(&mrt_lock);
1642 
1643 			if (copy_to_user(arg, &vr, sizeof(vr)))
1644 				return -EFAULT;
1645 			return 0;
1646 		}
1647 		read_unlock(&mrt_lock);
1648 		return -EADDRNOTAVAIL;
1649 	case SIOCGETSGCNT:
1650 		if (copy_from_user(&sr, arg, sizeof(sr)))
1651 			return -EFAULT;
1652 
1653 		rcu_read_lock();
1654 		c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1655 		if (c) {
1656 			sr.pktcnt = c->_c.mfc_un.res.pkt;
1657 			sr.bytecnt = c->_c.mfc_un.res.bytes;
1658 			sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1659 			rcu_read_unlock();
1660 
1661 			if (copy_to_user(arg, &sr, sizeof(sr)))
1662 				return -EFAULT;
1663 			return 0;
1664 		}
1665 		rcu_read_unlock();
1666 		return -EADDRNOTAVAIL;
1667 	default:
1668 		return -ENOIOCTLCMD;
1669 	}
1670 }
1671 
1672 #ifdef CONFIG_COMPAT
1673 struct compat_sioc_sg_req {
1674 	struct in_addr src;
1675 	struct in_addr grp;
1676 	compat_ulong_t pktcnt;
1677 	compat_ulong_t bytecnt;
1678 	compat_ulong_t wrong_if;
1679 };
1680 
1681 struct compat_sioc_vif_req {
1682 	vifi_t	vifi;		/* Which iface */
1683 	compat_ulong_t icount;
1684 	compat_ulong_t ocount;
1685 	compat_ulong_t ibytes;
1686 	compat_ulong_t obytes;
1687 };
1688 
1689 int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1690 {
1691 	struct compat_sioc_sg_req sr;
1692 	struct compat_sioc_vif_req vr;
1693 	struct vif_device *vif;
1694 	struct mfc_cache *c;
1695 	struct net *net = sock_net(sk);
1696 	struct mr_table *mrt;
1697 
1698 	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1699 	if (!mrt)
1700 		return -ENOENT;
1701 
1702 	switch (cmd) {
1703 	case SIOCGETVIFCNT:
1704 		if (copy_from_user(&vr, arg, sizeof(vr)))
1705 			return -EFAULT;
1706 		if (vr.vifi >= mrt->maxvif)
1707 			return -EINVAL;
1708 		vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
1709 		read_lock(&mrt_lock);
1710 		vif = &mrt->vif_table[vr.vifi];
1711 		if (VIF_EXISTS(mrt, vr.vifi)) {
1712 			vr.icount = vif->pkt_in;
1713 			vr.ocount = vif->pkt_out;
1714 			vr.ibytes = vif->bytes_in;
1715 			vr.obytes = vif->bytes_out;
1716 			read_unlock(&mrt_lock);
1717 
1718 			if (copy_to_user(arg, &vr, sizeof(vr)))
1719 				return -EFAULT;
1720 			return 0;
1721 		}
1722 		read_unlock(&mrt_lock);
1723 		return -EADDRNOTAVAIL;
1724 	case SIOCGETSGCNT:
1725 		if (copy_from_user(&sr, arg, sizeof(sr)))
1726 			return -EFAULT;
1727 
1728 		rcu_read_lock();
1729 		c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1730 		if (c) {
1731 			sr.pktcnt = c->_c.mfc_un.res.pkt;
1732 			sr.bytecnt = c->_c.mfc_un.res.bytes;
1733 			sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1734 			rcu_read_unlock();
1735 
1736 			if (copy_to_user(arg, &sr, sizeof(sr)))
1737 				return -EFAULT;
1738 			return 0;
1739 		}
1740 		rcu_read_unlock();
1741 		return -EADDRNOTAVAIL;
1742 	default:
1743 		return -ENOIOCTLCMD;
1744 	}
1745 }
1746 #endif
1747 
1748 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1749 {
1750 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1751 	struct net *net = dev_net(dev);
1752 	struct mr_table *mrt;
1753 	struct vif_device *v;
1754 	int ct;
1755 
1756 	if (event != NETDEV_UNREGISTER)
1757 		return NOTIFY_DONE;
1758 
1759 	ipmr_for_each_table(mrt, net) {
1760 		v = &mrt->vif_table[0];
1761 		for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1762 			if (v->dev == dev)
1763 				vif_delete(mrt, ct, 1, NULL);
1764 		}
1765 	}
1766 	return NOTIFY_DONE;
1767 }
1768 
1769 static struct notifier_block ip_mr_notifier = {
1770 	.notifier_call = ipmr_device_event,
1771 };
1772 
1773 /* Encapsulate a packet by attaching a valid IPIP header to it.
1774  * This avoids tunnel drivers and other mess and gives us the speed so
1775  * important for multicast video.
1776  */
1777 static void ip_encap(struct net *net, struct sk_buff *skb,
1778 		     __be32 saddr, __be32 daddr)
1779 {
1780 	struct iphdr *iph;
1781 	const struct iphdr *old_iph = ip_hdr(skb);
1782 
1783 	skb_push(skb, sizeof(struct iphdr));
1784 	skb->transport_header = skb->network_header;
1785 	skb_reset_network_header(skb);
1786 	iph = ip_hdr(skb);
1787 
1788 	iph->version	=	4;
1789 	iph->tos	=	old_iph->tos;
1790 	iph->ttl	=	old_iph->ttl;
1791 	iph->frag_off	=	0;
1792 	iph->daddr	=	daddr;
1793 	iph->saddr	=	saddr;
1794 	iph->protocol	=	IPPROTO_IPIP;
1795 	iph->ihl	=	5;
1796 	iph->tot_len	=	htons(skb->len);
1797 	ip_select_ident(net, skb, NULL);
1798 	ip_send_check(iph);
1799 
1800 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1801 	nf_reset_ct(skb);
1802 }
1803 
1804 static inline int ipmr_forward_finish(struct net *net, struct sock *sk,
1805 				      struct sk_buff *skb)
1806 {
1807 	struct ip_options *opt = &(IPCB(skb)->opt);
1808 
1809 	IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
1810 	IP_ADD_STATS(net, IPSTATS_MIB_OUTOCTETS, skb->len);
1811 
1812 	if (unlikely(opt->optlen))
1813 		ip_forward_options(skb);
1814 
1815 	return dst_output(net, sk, skb);
1816 }
1817 
1818 #ifdef CONFIG_NET_SWITCHDEV
1819 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1820 				   int in_vifi, int out_vifi)
1821 {
1822 	struct vif_device *out_vif = &mrt->vif_table[out_vifi];
1823 	struct vif_device *in_vif = &mrt->vif_table[in_vifi];
1824 
1825 	if (!skb->offload_l3_fwd_mark)
1826 		return false;
1827 	if (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
1828 		return false;
1829 	return netdev_phys_item_id_same(&out_vif->dev_parent_id,
1830 					&in_vif->dev_parent_id);
1831 }
1832 #else
1833 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1834 				   int in_vifi, int out_vifi)
1835 {
1836 	return false;
1837 }
1838 #endif
1839 
1840 /* Processing handlers for ipmr_forward */
1841 
1842 static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1843 			    int in_vifi, struct sk_buff *skb, int vifi)
1844 {
1845 	const struct iphdr *iph = ip_hdr(skb);
1846 	struct vif_device *vif = &mrt->vif_table[vifi];
1847 	struct net_device *dev;
1848 	struct rtable *rt;
1849 	struct flowi4 fl4;
1850 	int    encap = 0;
1851 
1852 	if (!vif->dev)
1853 		goto out_free;
1854 
1855 	if (vif->flags & VIFF_REGISTER) {
1856 		vif->pkt_out++;
1857 		vif->bytes_out += skb->len;
1858 		vif->dev->stats.tx_bytes += skb->len;
1859 		vif->dev->stats.tx_packets++;
1860 		ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1861 		goto out_free;
1862 	}
1863 
1864 	if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi))
1865 		goto out_free;
1866 
1867 	if (vif->flags & VIFF_TUNNEL) {
1868 		rt = ip_route_output_ports(net, &fl4, NULL,
1869 					   vif->remote, vif->local,
1870 					   0, 0,
1871 					   IPPROTO_IPIP,
1872 					   RT_TOS(iph->tos), vif->link);
1873 		if (IS_ERR(rt))
1874 			goto out_free;
1875 		encap = sizeof(struct iphdr);
1876 	} else {
1877 		rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1878 					   0, 0,
1879 					   IPPROTO_IPIP,
1880 					   RT_TOS(iph->tos), vif->link);
1881 		if (IS_ERR(rt))
1882 			goto out_free;
1883 	}
1884 
1885 	dev = rt->dst.dev;
1886 
1887 	if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1888 		/* Do not fragment multicasts. Alas, IPv4 does not
1889 		 * allow to send ICMP, so that packets will disappear
1890 		 * to blackhole.
1891 		 */
1892 		IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
1893 		ip_rt_put(rt);
1894 		goto out_free;
1895 	}
1896 
1897 	encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1898 
1899 	if (skb_cow(skb, encap)) {
1900 		ip_rt_put(rt);
1901 		goto out_free;
1902 	}
1903 
1904 	vif->pkt_out++;
1905 	vif->bytes_out += skb->len;
1906 
1907 	skb_dst_drop(skb);
1908 	skb_dst_set(skb, &rt->dst);
1909 	ip_decrease_ttl(ip_hdr(skb));
1910 
1911 	/* FIXME: forward and output firewalls used to be called here.
1912 	 * What do we do with netfilter? -- RR
1913 	 */
1914 	if (vif->flags & VIFF_TUNNEL) {
1915 		ip_encap(net, skb, vif->local, vif->remote);
1916 		/* FIXME: extra output firewall step used to be here. --RR */
1917 		vif->dev->stats.tx_packets++;
1918 		vif->dev->stats.tx_bytes += skb->len;
1919 	}
1920 
1921 	IPCB(skb)->flags |= IPSKB_FORWARDED;
1922 
1923 	/* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1924 	 * not only before forwarding, but after forwarding on all output
1925 	 * interfaces. It is clear, if mrouter runs a multicasting
1926 	 * program, it should receive packets not depending to what interface
1927 	 * program is joined.
1928 	 * If we will not make it, the program will have to join on all
1929 	 * interfaces. On the other hand, multihoming host (or router, but
1930 	 * not mrouter) cannot join to more than one interface - it will
1931 	 * result in receiving multiple packets.
1932 	 */
1933 	NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
1934 		net, NULL, skb, skb->dev, dev,
1935 		ipmr_forward_finish);
1936 	return;
1937 
1938 out_free:
1939 	kfree_skb(skb);
1940 }
1941 
1942 static int ipmr_find_vif(struct mr_table *mrt, struct net_device *dev)
1943 {
1944 	int ct;
1945 
1946 	for (ct = mrt->maxvif-1; ct >= 0; ct--) {
1947 		if (mrt->vif_table[ct].dev == dev)
1948 			break;
1949 	}
1950 	return ct;
1951 }
1952 
1953 /* "local" means that we should preserve one skb (for local delivery) */
1954 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1955 			  struct net_device *dev, struct sk_buff *skb,
1956 			  struct mfc_cache *c, int local)
1957 {
1958 	int true_vifi = ipmr_find_vif(mrt, dev);
1959 	int psend = -1;
1960 	int vif, ct;
1961 
1962 	vif = c->_c.mfc_parent;
1963 	c->_c.mfc_un.res.pkt++;
1964 	c->_c.mfc_un.res.bytes += skb->len;
1965 	c->_c.mfc_un.res.lastuse = jiffies;
1966 
1967 	if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1968 		struct mfc_cache *cache_proxy;
1969 
1970 		/* For an (*,G) entry, we only check that the incomming
1971 		 * interface is part of the static tree.
1972 		 */
1973 		cache_proxy = mr_mfc_find_any_parent(mrt, vif);
1974 		if (cache_proxy &&
1975 		    cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
1976 			goto forward;
1977 	}
1978 
1979 	/* Wrong interface: drop packet and (maybe) send PIM assert. */
1980 	if (mrt->vif_table[vif].dev != dev) {
1981 		if (rt_is_output_route(skb_rtable(skb))) {
1982 			/* It is our own packet, looped back.
1983 			 * Very complicated situation...
1984 			 *
1985 			 * The best workaround until routing daemons will be
1986 			 * fixed is not to redistribute packet, if it was
1987 			 * send through wrong interface. It means, that
1988 			 * multicast applications WILL NOT work for
1989 			 * (S,G), which have default multicast route pointing
1990 			 * to wrong oif. In any case, it is not a good
1991 			 * idea to use multicasting applications on router.
1992 			 */
1993 			goto dont_forward;
1994 		}
1995 
1996 		c->_c.mfc_un.res.wrong_if++;
1997 
1998 		if (true_vifi >= 0 && mrt->mroute_do_assert &&
1999 		    /* pimsm uses asserts, when switching from RPT to SPT,
2000 		     * so that we cannot check that packet arrived on an oif.
2001 		     * It is bad, but otherwise we would need to move pretty
2002 		     * large chunk of pimd to kernel. Ough... --ANK
2003 		     */
2004 		    (mrt->mroute_do_pim ||
2005 		     c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
2006 		    time_after(jiffies,
2007 			       c->_c.mfc_un.res.last_assert +
2008 			       MFC_ASSERT_THRESH)) {
2009 			c->_c.mfc_un.res.last_assert = jiffies;
2010 			ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
2011 			if (mrt->mroute_do_wrvifwhole)
2012 				ipmr_cache_report(mrt, skb, true_vifi,
2013 						  IGMPMSG_WRVIFWHOLE);
2014 		}
2015 		goto dont_forward;
2016 	}
2017 
2018 forward:
2019 	mrt->vif_table[vif].pkt_in++;
2020 	mrt->vif_table[vif].bytes_in += skb->len;
2021 
2022 	/* Forward the frame */
2023 	if (c->mfc_origin == htonl(INADDR_ANY) &&
2024 	    c->mfc_mcastgrp == htonl(INADDR_ANY)) {
2025 		if (true_vifi >= 0 &&
2026 		    true_vifi != c->_c.mfc_parent &&
2027 		    ip_hdr(skb)->ttl >
2028 				c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
2029 			/* It's an (*,*) entry and the packet is not coming from
2030 			 * the upstream: forward the packet to the upstream
2031 			 * only.
2032 			 */
2033 			psend = c->_c.mfc_parent;
2034 			goto last_forward;
2035 		}
2036 		goto dont_forward;
2037 	}
2038 	for (ct = c->_c.mfc_un.res.maxvif - 1;
2039 	     ct >= c->_c.mfc_un.res.minvif; ct--) {
2040 		/* For (*,G) entry, don't forward to the incoming interface */
2041 		if ((c->mfc_origin != htonl(INADDR_ANY) ||
2042 		     ct != true_vifi) &&
2043 		    ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) {
2044 			if (psend != -1) {
2045 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2046 
2047 				if (skb2)
2048 					ipmr_queue_xmit(net, mrt, true_vifi,
2049 							skb2, psend);
2050 			}
2051 			psend = ct;
2052 		}
2053 	}
2054 last_forward:
2055 	if (psend != -1) {
2056 		if (local) {
2057 			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2058 
2059 			if (skb2)
2060 				ipmr_queue_xmit(net, mrt, true_vifi, skb2,
2061 						psend);
2062 		} else {
2063 			ipmr_queue_xmit(net, mrt, true_vifi, skb, psend);
2064 			return;
2065 		}
2066 	}
2067 
2068 dont_forward:
2069 	if (!local)
2070 		kfree_skb(skb);
2071 }
2072 
2073 static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
2074 {
2075 	struct rtable *rt = skb_rtable(skb);
2076 	struct iphdr *iph = ip_hdr(skb);
2077 	struct flowi4 fl4 = {
2078 		.daddr = iph->daddr,
2079 		.saddr = iph->saddr,
2080 		.flowi4_tos = RT_TOS(iph->tos),
2081 		.flowi4_oif = (rt_is_output_route(rt) ?
2082 			       skb->dev->ifindex : 0),
2083 		.flowi4_iif = (rt_is_output_route(rt) ?
2084 			       LOOPBACK_IFINDEX :
2085 			       skb->dev->ifindex),
2086 		.flowi4_mark = skb->mark,
2087 	};
2088 	struct mr_table *mrt;
2089 	int err;
2090 
2091 	err = ipmr_fib_lookup(net, &fl4, &mrt);
2092 	if (err)
2093 		return ERR_PTR(err);
2094 	return mrt;
2095 }
2096 
2097 /* Multicast packets for forwarding arrive here
2098  * Called with rcu_read_lock();
2099  */
2100 int ip_mr_input(struct sk_buff *skb)
2101 {
2102 	struct mfc_cache *cache;
2103 	struct net *net = dev_net(skb->dev);
2104 	int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
2105 	struct mr_table *mrt;
2106 	struct net_device *dev;
2107 
2108 	/* skb->dev passed in is the loX master dev for vrfs.
2109 	 * As there are no vifs associated with loopback devices,
2110 	 * get the proper interface that does have a vif associated with it.
2111 	 */
2112 	dev = skb->dev;
2113 	if (netif_is_l3_master(skb->dev)) {
2114 		dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
2115 		if (!dev) {
2116 			kfree_skb(skb);
2117 			return -ENODEV;
2118 		}
2119 	}
2120 
2121 	/* Packet is looped back after forward, it should not be
2122 	 * forwarded second time, but still can be delivered locally.
2123 	 */
2124 	if (IPCB(skb)->flags & IPSKB_FORWARDED)
2125 		goto dont_forward;
2126 
2127 	mrt = ipmr_rt_fib_lookup(net, skb);
2128 	if (IS_ERR(mrt)) {
2129 		kfree_skb(skb);
2130 		return PTR_ERR(mrt);
2131 	}
2132 	if (!local) {
2133 		if (IPCB(skb)->opt.router_alert) {
2134 			if (ip_call_ra_chain(skb))
2135 				return 0;
2136 		} else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
2137 			/* IGMPv1 (and broken IGMPv2 implementations sort of
2138 			 * Cisco IOS <= 11.2(8)) do not put router alert
2139 			 * option to IGMP packets destined to routable
2140 			 * groups. It is very bad, because it means
2141 			 * that we can forward NO IGMP messages.
2142 			 */
2143 			struct sock *mroute_sk;
2144 
2145 			mroute_sk = rcu_dereference(mrt->mroute_sk);
2146 			if (mroute_sk) {
2147 				nf_reset_ct(skb);
2148 				raw_rcv(mroute_sk, skb);
2149 				return 0;
2150 			}
2151 		    }
2152 	}
2153 
2154 	/* already under rcu_read_lock() */
2155 	cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
2156 	if (!cache) {
2157 		int vif = ipmr_find_vif(mrt, dev);
2158 
2159 		if (vif >= 0)
2160 			cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
2161 						    vif);
2162 	}
2163 
2164 	/* No usable cache entry */
2165 	if (!cache) {
2166 		int vif;
2167 
2168 		if (local) {
2169 			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2170 			ip_local_deliver(skb);
2171 			if (!skb2)
2172 				return -ENOBUFS;
2173 			skb = skb2;
2174 		}
2175 
2176 		read_lock(&mrt_lock);
2177 		vif = ipmr_find_vif(mrt, dev);
2178 		if (vif >= 0) {
2179 			int err2 = ipmr_cache_unresolved(mrt, vif, skb, dev);
2180 			read_unlock(&mrt_lock);
2181 
2182 			return err2;
2183 		}
2184 		read_unlock(&mrt_lock);
2185 		kfree_skb(skb);
2186 		return -ENODEV;
2187 	}
2188 
2189 	read_lock(&mrt_lock);
2190 	ip_mr_forward(net, mrt, dev, skb, cache, local);
2191 	read_unlock(&mrt_lock);
2192 
2193 	if (local)
2194 		return ip_local_deliver(skb);
2195 
2196 	return 0;
2197 
2198 dont_forward:
2199 	if (local)
2200 		return ip_local_deliver(skb);
2201 	kfree_skb(skb);
2202 	return 0;
2203 }
2204 
2205 #ifdef CONFIG_IP_PIMSM_V1
2206 /* Handle IGMP messages of PIMv1 */
2207 int pim_rcv_v1(struct sk_buff *skb)
2208 {
2209 	struct igmphdr *pim;
2210 	struct net *net = dev_net(skb->dev);
2211 	struct mr_table *mrt;
2212 
2213 	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2214 		goto drop;
2215 
2216 	pim = igmp_hdr(skb);
2217 
2218 	mrt = ipmr_rt_fib_lookup(net, skb);
2219 	if (IS_ERR(mrt))
2220 		goto drop;
2221 	if (!mrt->mroute_do_pim ||
2222 	    pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
2223 		goto drop;
2224 
2225 	if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2226 drop:
2227 		kfree_skb(skb);
2228 	}
2229 	return 0;
2230 }
2231 #endif
2232 
2233 #ifdef CONFIG_IP_PIMSM_V2
2234 static int pim_rcv(struct sk_buff *skb)
2235 {
2236 	struct pimreghdr *pim;
2237 	struct net *net = dev_net(skb->dev);
2238 	struct mr_table *mrt;
2239 
2240 	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2241 		goto drop;
2242 
2243 	pim = (struct pimreghdr *)skb_transport_header(skb);
2244 	if (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) ||
2245 	    (pim->flags & PIM_NULL_REGISTER) ||
2246 	    (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
2247 	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
2248 		goto drop;
2249 
2250 	mrt = ipmr_rt_fib_lookup(net, skb);
2251 	if (IS_ERR(mrt))
2252 		goto drop;
2253 	if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2254 drop:
2255 		kfree_skb(skb);
2256 	}
2257 	return 0;
2258 }
2259 #endif
2260 
2261 int ipmr_get_route(struct net *net, struct sk_buff *skb,
2262 		   __be32 saddr, __be32 daddr,
2263 		   struct rtmsg *rtm, u32 portid)
2264 {
2265 	struct mfc_cache *cache;
2266 	struct mr_table *mrt;
2267 	int err;
2268 
2269 	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2270 	if (!mrt)
2271 		return -ENOENT;
2272 
2273 	rcu_read_lock();
2274 	cache = ipmr_cache_find(mrt, saddr, daddr);
2275 	if (!cache && skb->dev) {
2276 		int vif = ipmr_find_vif(mrt, skb->dev);
2277 
2278 		if (vif >= 0)
2279 			cache = ipmr_cache_find_any(mrt, daddr, vif);
2280 	}
2281 	if (!cache) {
2282 		struct sk_buff *skb2;
2283 		struct iphdr *iph;
2284 		struct net_device *dev;
2285 		int vif = -1;
2286 
2287 		dev = skb->dev;
2288 		read_lock(&mrt_lock);
2289 		if (dev)
2290 			vif = ipmr_find_vif(mrt, dev);
2291 		if (vif < 0) {
2292 			read_unlock(&mrt_lock);
2293 			rcu_read_unlock();
2294 			return -ENODEV;
2295 		}
2296 
2297 		skb2 = skb_realloc_headroom(skb, sizeof(struct iphdr));
2298 		if (!skb2) {
2299 			read_unlock(&mrt_lock);
2300 			rcu_read_unlock();
2301 			return -ENOMEM;
2302 		}
2303 
2304 		NETLINK_CB(skb2).portid = portid;
2305 		skb_push(skb2, sizeof(struct iphdr));
2306 		skb_reset_network_header(skb2);
2307 		iph = ip_hdr(skb2);
2308 		iph->ihl = sizeof(struct iphdr) >> 2;
2309 		iph->saddr = saddr;
2310 		iph->daddr = daddr;
2311 		iph->version = 0;
2312 		err = ipmr_cache_unresolved(mrt, vif, skb2, dev);
2313 		read_unlock(&mrt_lock);
2314 		rcu_read_unlock();
2315 		return err;
2316 	}
2317 
2318 	read_lock(&mrt_lock);
2319 	err = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
2320 	read_unlock(&mrt_lock);
2321 	rcu_read_unlock();
2322 	return err;
2323 }
2324 
2325 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2326 			    u32 portid, u32 seq, struct mfc_cache *c, int cmd,
2327 			    int flags)
2328 {
2329 	struct nlmsghdr *nlh;
2330 	struct rtmsg *rtm;
2331 	int err;
2332 
2333 	nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2334 	if (!nlh)
2335 		return -EMSGSIZE;
2336 
2337 	rtm = nlmsg_data(nlh);
2338 	rtm->rtm_family   = RTNL_FAMILY_IPMR;
2339 	rtm->rtm_dst_len  = 32;
2340 	rtm->rtm_src_len  = 32;
2341 	rtm->rtm_tos      = 0;
2342 	rtm->rtm_table    = mrt->id;
2343 	if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2344 		goto nla_put_failure;
2345 	rtm->rtm_type     = RTN_MULTICAST;
2346 	rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2347 	if (c->_c.mfc_flags & MFC_STATIC)
2348 		rtm->rtm_protocol = RTPROT_STATIC;
2349 	else
2350 		rtm->rtm_protocol = RTPROT_MROUTED;
2351 	rtm->rtm_flags    = 0;
2352 
2353 	if (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) ||
2354 	    nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp))
2355 		goto nla_put_failure;
2356 	err = mr_fill_mroute(mrt, skb, &c->_c, rtm);
2357 	/* do not break the dump if cache is unresolved */
2358 	if (err < 0 && err != -ENOENT)
2359 		goto nla_put_failure;
2360 
2361 	nlmsg_end(skb, nlh);
2362 	return 0;
2363 
2364 nla_put_failure:
2365 	nlmsg_cancel(skb, nlh);
2366 	return -EMSGSIZE;
2367 }
2368 
2369 static int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2370 			     u32 portid, u32 seq, struct mr_mfc *c, int cmd,
2371 			     int flags)
2372 {
2373 	return ipmr_fill_mroute(mrt, skb, portid, seq, (struct mfc_cache *)c,
2374 				cmd, flags);
2375 }
2376 
2377 static size_t mroute_msgsize(bool unresolved, int maxvif)
2378 {
2379 	size_t len =
2380 		NLMSG_ALIGN(sizeof(struct rtmsg))
2381 		+ nla_total_size(4)	/* RTA_TABLE */
2382 		+ nla_total_size(4)	/* RTA_SRC */
2383 		+ nla_total_size(4)	/* RTA_DST */
2384 		;
2385 
2386 	if (!unresolved)
2387 		len = len
2388 		      + nla_total_size(4)	/* RTA_IIF */
2389 		      + nla_total_size(0)	/* RTA_MULTIPATH */
2390 		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2391 						/* RTA_MFC_STATS */
2392 		      + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
2393 		;
2394 
2395 	return len;
2396 }
2397 
2398 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2399 				 int cmd)
2400 {
2401 	struct net *net = read_pnet(&mrt->net);
2402 	struct sk_buff *skb;
2403 	int err = -ENOBUFS;
2404 
2405 	skb = nlmsg_new(mroute_msgsize(mfc->_c.mfc_parent >= MAXVIFS,
2406 				       mrt->maxvif),
2407 			GFP_ATOMIC);
2408 	if (!skb)
2409 		goto errout;
2410 
2411 	err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2412 	if (err < 0)
2413 		goto errout;
2414 
2415 	rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2416 	return;
2417 
2418 errout:
2419 	kfree_skb(skb);
2420 	if (err < 0)
2421 		rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
2422 }
2423 
2424 static size_t igmpmsg_netlink_msgsize(size_t payloadlen)
2425 {
2426 	size_t len =
2427 		NLMSG_ALIGN(sizeof(struct rtgenmsg))
2428 		+ nla_total_size(1)	/* IPMRA_CREPORT_MSGTYPE */
2429 		+ nla_total_size(4)	/* IPMRA_CREPORT_VIF_ID */
2430 		+ nla_total_size(4)	/* IPMRA_CREPORT_SRC_ADDR */
2431 		+ nla_total_size(4)	/* IPMRA_CREPORT_DST_ADDR */
2432 					/* IPMRA_CREPORT_PKT */
2433 		+ nla_total_size(payloadlen)
2434 		;
2435 
2436 	return len;
2437 }
2438 
2439 static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt)
2440 {
2441 	struct net *net = read_pnet(&mrt->net);
2442 	struct nlmsghdr *nlh;
2443 	struct rtgenmsg *rtgenm;
2444 	struct igmpmsg *msg;
2445 	struct sk_buff *skb;
2446 	struct nlattr *nla;
2447 	int payloadlen;
2448 
2449 	payloadlen = pkt->len - sizeof(struct igmpmsg);
2450 	msg = (struct igmpmsg *)skb_network_header(pkt);
2451 
2452 	skb = nlmsg_new(igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2453 	if (!skb)
2454 		goto errout;
2455 
2456 	nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
2457 			sizeof(struct rtgenmsg), 0);
2458 	if (!nlh)
2459 		goto errout;
2460 	rtgenm = nlmsg_data(nlh);
2461 	rtgenm->rtgen_family = RTNL_FAMILY_IPMR;
2462 	if (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) ||
2463 	    nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif) ||
2464 	    nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR,
2465 			    msg->im_src.s_addr) ||
2466 	    nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR,
2467 			    msg->im_dst.s_addr))
2468 		goto nla_put_failure;
2469 
2470 	nla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen);
2471 	if (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg),
2472 				  nla_data(nla), payloadlen))
2473 		goto nla_put_failure;
2474 
2475 	nlmsg_end(skb, nlh);
2476 
2477 	rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
2478 	return;
2479 
2480 nla_put_failure:
2481 	nlmsg_cancel(skb, nlh);
2482 errout:
2483 	kfree_skb(skb);
2484 	rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS);
2485 }
2486 
2487 static int ipmr_rtm_valid_getroute_req(struct sk_buff *skb,
2488 				       const struct nlmsghdr *nlh,
2489 				       struct nlattr **tb,
2490 				       struct netlink_ext_ack *extack)
2491 {
2492 	struct rtmsg *rtm;
2493 	int i, err;
2494 
2495 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2496 		NL_SET_ERR_MSG(extack, "ipv4: Invalid header for multicast route get request");
2497 		return -EINVAL;
2498 	}
2499 
2500 	if (!netlink_strict_get_check(skb))
2501 		return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
2502 					      rtm_ipv4_policy, extack);
2503 
2504 	rtm = nlmsg_data(nlh);
2505 	if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) ||
2506 	    (rtm->rtm_dst_len && rtm->rtm_dst_len != 32) ||
2507 	    rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol ||
2508 	    rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) {
2509 		NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for multicast route get request");
2510 		return -EINVAL;
2511 	}
2512 
2513 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2514 					    rtm_ipv4_policy, extack);
2515 	if (err)
2516 		return err;
2517 
2518 	if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
2519 	    (tb[RTA_DST] && !rtm->rtm_dst_len)) {
2520 		NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4");
2521 		return -EINVAL;
2522 	}
2523 
2524 	for (i = 0; i <= RTA_MAX; i++) {
2525 		if (!tb[i])
2526 			continue;
2527 
2528 		switch (i) {
2529 		case RTA_SRC:
2530 		case RTA_DST:
2531 		case RTA_TABLE:
2532 			break;
2533 		default:
2534 			NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in multicast route get request");
2535 			return -EINVAL;
2536 		}
2537 	}
2538 
2539 	return 0;
2540 }
2541 
2542 static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2543 			     struct netlink_ext_ack *extack)
2544 {
2545 	struct net *net = sock_net(in_skb->sk);
2546 	struct nlattr *tb[RTA_MAX + 1];
2547 	struct sk_buff *skb = NULL;
2548 	struct mfc_cache *cache;
2549 	struct mr_table *mrt;
2550 	__be32 src, grp;
2551 	u32 tableid;
2552 	int err;
2553 
2554 	err = ipmr_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
2555 	if (err < 0)
2556 		goto errout;
2557 
2558 	src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
2559 	grp = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
2560 	tableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0;
2561 
2562 	mrt = ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT);
2563 	if (!mrt) {
2564 		err = -ENOENT;
2565 		goto errout_free;
2566 	}
2567 
2568 	/* entries are added/deleted only under RTNL */
2569 	rcu_read_lock();
2570 	cache = ipmr_cache_find(mrt, src, grp);
2571 	rcu_read_unlock();
2572 	if (!cache) {
2573 		err = -ENOENT;
2574 		goto errout_free;
2575 	}
2576 
2577 	skb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL);
2578 	if (!skb) {
2579 		err = -ENOBUFS;
2580 		goto errout_free;
2581 	}
2582 
2583 	err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
2584 			       nlh->nlmsg_seq, cache,
2585 			       RTM_NEWROUTE, 0);
2586 	if (err < 0)
2587 		goto errout_free;
2588 
2589 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2590 
2591 errout:
2592 	return err;
2593 
2594 errout_free:
2595 	kfree_skb(skb);
2596 	goto errout;
2597 }
2598 
2599 static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2600 {
2601 	struct fib_dump_filter filter = {};
2602 	int err;
2603 
2604 	if (cb->strict_check) {
2605 		err = ip_valid_fib_dump_req(sock_net(skb->sk), cb->nlh,
2606 					    &filter, cb);
2607 		if (err < 0)
2608 			return err;
2609 	}
2610 
2611 	if (filter.table_id) {
2612 		struct mr_table *mrt;
2613 
2614 		mrt = ipmr_get_table(sock_net(skb->sk), filter.table_id);
2615 		if (!mrt) {
2616 			if (rtnl_msg_family(cb->nlh) != RTNL_FAMILY_IPMR)
2617 				return skb->len;
2618 
2619 			NL_SET_ERR_MSG(cb->extack, "ipv4: MR table does not exist");
2620 			return -ENOENT;
2621 		}
2622 		err = mr_table_dump(mrt, skb, cb, _ipmr_fill_mroute,
2623 				    &mfc_unres_lock, &filter);
2624 		return skb->len ? : err;
2625 	}
2626 
2627 	return mr_rtm_dumproute(skb, cb, ipmr_mr_table_iter,
2628 				_ipmr_fill_mroute, &mfc_unres_lock, &filter);
2629 }
2630 
2631 static const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = {
2632 	[RTA_SRC]	= { .type = NLA_U32 },
2633 	[RTA_DST]	= { .type = NLA_U32 },
2634 	[RTA_IIF]	= { .type = NLA_U32 },
2635 	[RTA_TABLE]	= { .type = NLA_U32 },
2636 	[RTA_MULTIPATH]	= { .len = sizeof(struct rtnexthop) },
2637 };
2638 
2639 static bool ipmr_rtm_validate_proto(unsigned char rtm_protocol)
2640 {
2641 	switch (rtm_protocol) {
2642 	case RTPROT_STATIC:
2643 	case RTPROT_MROUTED:
2644 		return true;
2645 	}
2646 	return false;
2647 }
2648 
2649 static int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc)
2650 {
2651 	struct rtnexthop *rtnh = nla_data(nla);
2652 	int remaining = nla_len(nla), vifi = 0;
2653 
2654 	while (rtnh_ok(rtnh, remaining)) {
2655 		mfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops;
2656 		if (++vifi == MAXVIFS)
2657 			break;
2658 		rtnh = rtnh_next(rtnh, &remaining);
2659 	}
2660 
2661 	return remaining > 0 ? -EINVAL : vifi;
2662 }
2663 
2664 /* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY */
2665 static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh,
2666 			    struct mfcctl *mfcc, int *mrtsock,
2667 			    struct mr_table **mrtret,
2668 			    struct netlink_ext_ack *extack)
2669 {
2670 	struct net_device *dev = NULL;
2671 	u32 tblid = RT_TABLE_DEFAULT;
2672 	struct mr_table *mrt;
2673 	struct nlattr *attr;
2674 	struct rtmsg *rtm;
2675 	int ret, rem;
2676 
2677 	ret = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX,
2678 					rtm_ipmr_policy, extack);
2679 	if (ret < 0)
2680 		goto out;
2681 	rtm = nlmsg_data(nlh);
2682 
2683 	ret = -EINVAL;
2684 	if (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 ||
2685 	    rtm->rtm_type != RTN_MULTICAST ||
2686 	    rtm->rtm_scope != RT_SCOPE_UNIVERSE ||
2687 	    !ipmr_rtm_validate_proto(rtm->rtm_protocol))
2688 		goto out;
2689 
2690 	memset(mfcc, 0, sizeof(*mfcc));
2691 	mfcc->mfcc_parent = -1;
2692 	ret = 0;
2693 	nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) {
2694 		switch (nla_type(attr)) {
2695 		case RTA_SRC:
2696 			mfcc->mfcc_origin.s_addr = nla_get_be32(attr);
2697 			break;
2698 		case RTA_DST:
2699 			mfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr);
2700 			break;
2701 		case RTA_IIF:
2702 			dev = __dev_get_by_index(net, nla_get_u32(attr));
2703 			if (!dev) {
2704 				ret = -ENODEV;
2705 				goto out;
2706 			}
2707 			break;
2708 		case RTA_MULTIPATH:
2709 			if (ipmr_nla_get_ttls(attr, mfcc) < 0) {
2710 				ret = -EINVAL;
2711 				goto out;
2712 			}
2713 			break;
2714 		case RTA_PREFSRC:
2715 			ret = 1;
2716 			break;
2717 		case RTA_TABLE:
2718 			tblid = nla_get_u32(attr);
2719 			break;
2720 		}
2721 	}
2722 	mrt = ipmr_get_table(net, tblid);
2723 	if (!mrt) {
2724 		ret = -ENOENT;
2725 		goto out;
2726 	}
2727 	*mrtret = mrt;
2728 	*mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0;
2729 	if (dev)
2730 		mfcc->mfcc_parent = ipmr_find_vif(mrt, dev);
2731 
2732 out:
2733 	return ret;
2734 }
2735 
2736 /* takes care of both newroute and delroute */
2737 static int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh,
2738 			  struct netlink_ext_ack *extack)
2739 {
2740 	struct net *net = sock_net(skb->sk);
2741 	int ret, mrtsock, parent;
2742 	struct mr_table *tbl;
2743 	struct mfcctl mfcc;
2744 
2745 	mrtsock = 0;
2746 	tbl = NULL;
2747 	ret = rtm_to_ipmr_mfcc(net, nlh, &mfcc, &mrtsock, &tbl, extack);
2748 	if (ret < 0)
2749 		return ret;
2750 
2751 	parent = ret ? mfcc.mfcc_parent : -1;
2752 	if (nlh->nlmsg_type == RTM_NEWROUTE)
2753 		return ipmr_mfc_add(net, tbl, &mfcc, mrtsock, parent);
2754 	else
2755 		return ipmr_mfc_delete(tbl, &mfcc, parent);
2756 }
2757 
2758 static bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb)
2759 {
2760 	u32 queue_len = atomic_read(&mrt->cache_resolve_queue_len);
2761 
2762 	if (nla_put_u32(skb, IPMRA_TABLE_ID, mrt->id) ||
2763 	    nla_put_u32(skb, IPMRA_TABLE_CACHE_RES_QUEUE_LEN, queue_len) ||
2764 	    nla_put_s32(skb, IPMRA_TABLE_MROUTE_REG_VIF_NUM,
2765 			mrt->mroute_reg_vif_num) ||
2766 	    nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_ASSERT,
2767 		       mrt->mroute_do_assert) ||
2768 	    nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_PIM, mrt->mroute_do_pim) ||
2769 	    nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE,
2770 		       mrt->mroute_do_wrvifwhole))
2771 		return false;
2772 
2773 	return true;
2774 }
2775 
2776 static bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb)
2777 {
2778 	struct nlattr *vif_nest;
2779 	struct vif_device *vif;
2780 
2781 	/* if the VIF doesn't exist just continue */
2782 	if (!VIF_EXISTS(mrt, vifid))
2783 		return true;
2784 
2785 	vif = &mrt->vif_table[vifid];
2786 	vif_nest = nla_nest_start_noflag(skb, IPMRA_VIF);
2787 	if (!vif_nest)
2788 		return false;
2789 	if (nla_put_u32(skb, IPMRA_VIFA_IFINDEX, vif->dev->ifindex) ||
2790 	    nla_put_u32(skb, IPMRA_VIFA_VIF_ID, vifid) ||
2791 	    nla_put_u16(skb, IPMRA_VIFA_FLAGS, vif->flags) ||
2792 	    nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_IN, vif->bytes_in,
2793 			      IPMRA_VIFA_PAD) ||
2794 	    nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_OUT, vif->bytes_out,
2795 			      IPMRA_VIFA_PAD) ||
2796 	    nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_IN, vif->pkt_in,
2797 			      IPMRA_VIFA_PAD) ||
2798 	    nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_OUT, vif->pkt_out,
2799 			      IPMRA_VIFA_PAD) ||
2800 	    nla_put_be32(skb, IPMRA_VIFA_LOCAL_ADDR, vif->local) ||
2801 	    nla_put_be32(skb, IPMRA_VIFA_REMOTE_ADDR, vif->remote)) {
2802 		nla_nest_cancel(skb, vif_nest);
2803 		return false;
2804 	}
2805 	nla_nest_end(skb, vif_nest);
2806 
2807 	return true;
2808 }
2809 
2810 static int ipmr_valid_dumplink(const struct nlmsghdr *nlh,
2811 			       struct netlink_ext_ack *extack)
2812 {
2813 	struct ifinfomsg *ifm;
2814 
2815 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
2816 		NL_SET_ERR_MSG(extack, "ipv4: Invalid header for ipmr link dump");
2817 		return -EINVAL;
2818 	}
2819 
2820 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
2821 		NL_SET_ERR_MSG(extack, "Invalid data after header in ipmr link dump");
2822 		return -EINVAL;
2823 	}
2824 
2825 	ifm = nlmsg_data(nlh);
2826 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
2827 	    ifm->ifi_change || ifm->ifi_index) {
2828 		NL_SET_ERR_MSG(extack, "Invalid values in header for ipmr link dump request");
2829 		return -EINVAL;
2830 	}
2831 
2832 	return 0;
2833 }
2834 
2835 static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb)
2836 {
2837 	struct net *net = sock_net(skb->sk);
2838 	struct nlmsghdr *nlh = NULL;
2839 	unsigned int t = 0, s_t;
2840 	unsigned int e = 0, s_e;
2841 	struct mr_table *mrt;
2842 
2843 	if (cb->strict_check) {
2844 		int err = ipmr_valid_dumplink(cb->nlh, cb->extack);
2845 
2846 		if (err < 0)
2847 			return err;
2848 	}
2849 
2850 	s_t = cb->args[0];
2851 	s_e = cb->args[1];
2852 
2853 	ipmr_for_each_table(mrt, net) {
2854 		struct nlattr *vifs, *af;
2855 		struct ifinfomsg *hdr;
2856 		u32 i;
2857 
2858 		if (t < s_t)
2859 			goto skip_table;
2860 		nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
2861 				cb->nlh->nlmsg_seq, RTM_NEWLINK,
2862 				sizeof(*hdr), NLM_F_MULTI);
2863 		if (!nlh)
2864 			break;
2865 
2866 		hdr = nlmsg_data(nlh);
2867 		memset(hdr, 0, sizeof(*hdr));
2868 		hdr->ifi_family = RTNL_FAMILY_IPMR;
2869 
2870 		af = nla_nest_start_noflag(skb, IFLA_AF_SPEC);
2871 		if (!af) {
2872 			nlmsg_cancel(skb, nlh);
2873 			goto out;
2874 		}
2875 
2876 		if (!ipmr_fill_table(mrt, skb)) {
2877 			nlmsg_cancel(skb, nlh);
2878 			goto out;
2879 		}
2880 
2881 		vifs = nla_nest_start_noflag(skb, IPMRA_TABLE_VIFS);
2882 		if (!vifs) {
2883 			nla_nest_end(skb, af);
2884 			nlmsg_end(skb, nlh);
2885 			goto out;
2886 		}
2887 		for (i = 0; i < mrt->maxvif; i++) {
2888 			if (e < s_e)
2889 				goto skip_entry;
2890 			if (!ipmr_fill_vif(mrt, i, skb)) {
2891 				nla_nest_end(skb, vifs);
2892 				nla_nest_end(skb, af);
2893 				nlmsg_end(skb, nlh);
2894 				goto out;
2895 			}
2896 skip_entry:
2897 			e++;
2898 		}
2899 		s_e = 0;
2900 		e = 0;
2901 		nla_nest_end(skb, vifs);
2902 		nla_nest_end(skb, af);
2903 		nlmsg_end(skb, nlh);
2904 skip_table:
2905 		t++;
2906 	}
2907 
2908 out:
2909 	cb->args[1] = e;
2910 	cb->args[0] = t;
2911 
2912 	return skb->len;
2913 }
2914 
2915 #ifdef CONFIG_PROC_FS
2916 /* The /proc interfaces to multicast routing :
2917  * /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2918  */
2919 
2920 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2921 	__acquires(mrt_lock)
2922 {
2923 	struct mr_vif_iter *iter = seq->private;
2924 	struct net *net = seq_file_net(seq);
2925 	struct mr_table *mrt;
2926 
2927 	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2928 	if (!mrt)
2929 		return ERR_PTR(-ENOENT);
2930 
2931 	iter->mrt = mrt;
2932 
2933 	read_lock(&mrt_lock);
2934 	return mr_vif_seq_start(seq, pos);
2935 }
2936 
2937 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2938 	__releases(mrt_lock)
2939 {
2940 	read_unlock(&mrt_lock);
2941 }
2942 
2943 static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2944 {
2945 	struct mr_vif_iter *iter = seq->private;
2946 	struct mr_table *mrt = iter->mrt;
2947 
2948 	if (v == SEQ_START_TOKEN) {
2949 		seq_puts(seq,
2950 			 "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
2951 	} else {
2952 		const struct vif_device *vif = v;
2953 		const char *name =  vif->dev ?
2954 				    vif->dev->name : "none";
2955 
2956 		seq_printf(seq,
2957 			   "%2td %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
2958 			   vif - mrt->vif_table,
2959 			   name, vif->bytes_in, vif->pkt_in,
2960 			   vif->bytes_out, vif->pkt_out,
2961 			   vif->flags, vif->local, vif->remote);
2962 	}
2963 	return 0;
2964 }
2965 
2966 static const struct seq_operations ipmr_vif_seq_ops = {
2967 	.start = ipmr_vif_seq_start,
2968 	.next  = mr_vif_seq_next,
2969 	.stop  = ipmr_vif_seq_stop,
2970 	.show  = ipmr_vif_seq_show,
2971 };
2972 
2973 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2974 {
2975 	struct net *net = seq_file_net(seq);
2976 	struct mr_table *mrt;
2977 
2978 	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2979 	if (!mrt)
2980 		return ERR_PTR(-ENOENT);
2981 
2982 	return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
2983 }
2984 
2985 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2986 {
2987 	int n;
2988 
2989 	if (v == SEQ_START_TOKEN) {
2990 		seq_puts(seq,
2991 		 "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
2992 	} else {
2993 		const struct mfc_cache *mfc = v;
2994 		const struct mr_mfc_iter *it = seq->private;
2995 		const struct mr_table *mrt = it->mrt;
2996 
2997 		seq_printf(seq, "%08X %08X %-3hd",
2998 			   (__force u32) mfc->mfc_mcastgrp,
2999 			   (__force u32) mfc->mfc_origin,
3000 			   mfc->_c.mfc_parent);
3001 
3002 		if (it->cache != &mrt->mfc_unres_queue) {
3003 			seq_printf(seq, " %8lu %8lu %8lu",
3004 				   mfc->_c.mfc_un.res.pkt,
3005 				   mfc->_c.mfc_un.res.bytes,
3006 				   mfc->_c.mfc_un.res.wrong_if);
3007 			for (n = mfc->_c.mfc_un.res.minvif;
3008 			     n < mfc->_c.mfc_un.res.maxvif; n++) {
3009 				if (VIF_EXISTS(mrt, n) &&
3010 				    mfc->_c.mfc_un.res.ttls[n] < 255)
3011 					seq_printf(seq,
3012 					   " %2d:%-3d",
3013 					   n, mfc->_c.mfc_un.res.ttls[n]);
3014 			}
3015 		} else {
3016 			/* unresolved mfc_caches don't contain
3017 			 * pkt, bytes and wrong_if values
3018 			 */
3019 			seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
3020 		}
3021 		seq_putc(seq, '\n');
3022 	}
3023 	return 0;
3024 }
3025 
3026 static const struct seq_operations ipmr_mfc_seq_ops = {
3027 	.start = ipmr_mfc_seq_start,
3028 	.next  = mr_mfc_seq_next,
3029 	.stop  = mr_mfc_seq_stop,
3030 	.show  = ipmr_mfc_seq_show,
3031 };
3032 #endif
3033 
3034 #ifdef CONFIG_IP_PIMSM_V2
3035 static const struct net_protocol pim_protocol = {
3036 	.handler	=	pim_rcv,
3037 	.netns_ok	=	1,
3038 };
3039 #endif
3040 
3041 static unsigned int ipmr_seq_read(struct net *net)
3042 {
3043 	ASSERT_RTNL();
3044 
3045 	return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
3046 }
3047 
3048 static int ipmr_dump(struct net *net, struct notifier_block *nb,
3049 		     struct netlink_ext_ack *extack)
3050 {
3051 	return mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump,
3052 		       ipmr_mr_table_iter, &mrt_lock, extack);
3053 }
3054 
3055 static const struct fib_notifier_ops ipmr_notifier_ops_template = {
3056 	.family		= RTNL_FAMILY_IPMR,
3057 	.fib_seq_read	= ipmr_seq_read,
3058 	.fib_dump	= ipmr_dump,
3059 	.owner		= THIS_MODULE,
3060 };
3061 
3062 static int __net_init ipmr_notifier_init(struct net *net)
3063 {
3064 	struct fib_notifier_ops *ops;
3065 
3066 	net->ipv4.ipmr_seq = 0;
3067 
3068 	ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net);
3069 	if (IS_ERR(ops))
3070 		return PTR_ERR(ops);
3071 	net->ipv4.ipmr_notifier_ops = ops;
3072 
3073 	return 0;
3074 }
3075 
3076 static void __net_exit ipmr_notifier_exit(struct net *net)
3077 {
3078 	fib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops);
3079 	net->ipv4.ipmr_notifier_ops = NULL;
3080 }
3081 
3082 /* Setup for IP multicast routing */
3083 static int __net_init ipmr_net_init(struct net *net)
3084 {
3085 	int err;
3086 
3087 	err = ipmr_notifier_init(net);
3088 	if (err)
3089 		goto ipmr_notifier_fail;
3090 
3091 	err = ipmr_rules_init(net);
3092 	if (err < 0)
3093 		goto ipmr_rules_fail;
3094 
3095 #ifdef CONFIG_PROC_FS
3096 	err = -ENOMEM;
3097 	if (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops,
3098 			sizeof(struct mr_vif_iter)))
3099 		goto proc_vif_fail;
3100 	if (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
3101 			sizeof(struct mr_mfc_iter)))
3102 		goto proc_cache_fail;
3103 #endif
3104 	return 0;
3105 
3106 #ifdef CONFIG_PROC_FS
3107 proc_cache_fail:
3108 	remove_proc_entry("ip_mr_vif", net->proc_net);
3109 proc_vif_fail:
3110 	ipmr_rules_exit(net);
3111 #endif
3112 ipmr_rules_fail:
3113 	ipmr_notifier_exit(net);
3114 ipmr_notifier_fail:
3115 	return err;
3116 }
3117 
3118 static void __net_exit ipmr_net_exit(struct net *net)
3119 {
3120 #ifdef CONFIG_PROC_FS
3121 	remove_proc_entry("ip_mr_cache", net->proc_net);
3122 	remove_proc_entry("ip_mr_vif", net->proc_net);
3123 #endif
3124 	ipmr_notifier_exit(net);
3125 	ipmr_rules_exit(net);
3126 }
3127 
3128 static struct pernet_operations ipmr_net_ops = {
3129 	.init = ipmr_net_init,
3130 	.exit = ipmr_net_exit,
3131 };
3132 
3133 int __init ip_mr_init(void)
3134 {
3135 	int err;
3136 
3137 	mrt_cachep = kmem_cache_create("ip_mrt_cache",
3138 				       sizeof(struct mfc_cache),
3139 				       0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
3140 				       NULL);
3141 
3142 	err = register_pernet_subsys(&ipmr_net_ops);
3143 	if (err)
3144 		goto reg_pernet_fail;
3145 
3146 	err = register_netdevice_notifier(&ip_mr_notifier);
3147 	if (err)
3148 		goto reg_notif_fail;
3149 #ifdef CONFIG_IP_PIMSM_V2
3150 	if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
3151 		pr_err("%s: can't add PIM protocol\n", __func__);
3152 		err = -EAGAIN;
3153 		goto add_proto_fail;
3154 	}
3155 #endif
3156 	rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
3157 		      ipmr_rtm_getroute, ipmr_rtm_dumproute, 0);
3158 	rtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE,
3159 		      ipmr_rtm_route, NULL, 0);
3160 	rtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE,
3161 		      ipmr_rtm_route, NULL, 0);
3162 
3163 	rtnl_register(RTNL_FAMILY_IPMR, RTM_GETLINK,
3164 		      NULL, ipmr_rtm_dumplink, 0);
3165 	return 0;
3166 
3167 #ifdef CONFIG_IP_PIMSM_V2
3168 add_proto_fail:
3169 	unregister_netdevice_notifier(&ip_mr_notifier);
3170 #endif
3171 reg_notif_fail:
3172 	unregister_pernet_subsys(&ipmr_net_ops);
3173 reg_pernet_fail:
3174 	kmem_cache_destroy(mrt_cachep);
3175 	return err;
3176 }
3177