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_SPINLOCK(mrt_lock);
81
82	static struct net_device *vif_dev_read(const struct vif_device *vif)
83	{
84	return rcu_dereference(vif->dev);
85	}
86
87	/* Multicast router control variables */
88
89	/* Special spinlock for queue of unresolved entries */
90	static DEFINE_SPINLOCK(mfc_unres_lock);
91
92	/* We return to original Alan's scheme. Hash table of resolved
93	* entries is changed only in process context and protected
94	* with weak lock mrt_lock. Queue of unresolved entries is protected
95	* with strong spinlock mfc_unres_lock.
96	*
97	* In this case data path is free of exclusive locks at all.
98	*/
99
100	static struct kmem_cache *mrt_cachep __ro_after_init;
101
102	static struct mr_table *ipmr_new_table(struct net *net, u32 id);
103	static void ipmr_free_table(struct mr_table *mrt);
104
105	static void ip_mr_forward(struct net *net, struct mr_table *mrt,
106	struct net_device *dev, struct sk_buff *skb,
107	struct mfc_cache *cache, int local);
108	static int ipmr_cache_report(const struct mr_table *mrt,
109	struct sk_buff *pkt, vifi_t vifi, int assert);
110	static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
111	int cmd);
112	static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt);
113	static void mroute_clean_tables(struct mr_table *mrt, int flags);
114	static void ipmr_expire_process(struct timer_list *t);
115
116	#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
117	#define ipmr_for_each_table(mrt, net) \
118	list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list, \
119	lockdep_rtnl_is_held() || \
120	list_empty(&net->ipv4.mr_tables))
121
122	static struct mr_table *ipmr_mr_table_iter(struct net *net,
123	struct mr_table *mrt)
124	{
125	struct mr_table *ret;
126
127	if (!mrt)
128	ret = list_entry_rcu(net->ipv4.mr_tables.next,
129	struct mr_table, list);
130	else
131	ret = list_entry_rcu(mrt->list.next,
132	struct mr_table, list);
133
134	if (&ret->list == &net->ipv4.mr_tables)
135	return NULL;
136	return ret;
137	}
138
139	static struct mr_table *ipmr_get_table(struct net *net, u32 id)
140	{
141	struct mr_table *mrt;
142
143	ipmr_for_each_table(mrt, net) {
144	if (mrt->id == id)
145	return mrt;
146	}
147	return NULL;
148	}
149
150	static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
151	struct mr_table **mrt)
152	{
153	int err;
154	struct ipmr_result res;
155	struct fib_lookup_arg arg = {
156	.result = &res,
157	.flags = FIB_LOOKUP_NOREF,
158	};
159
160	/* update flow if oif or iif point to device enslaved to l3mdev */
161	l3mdev_update_flow(net, fl: flowi4_to_flowi(fl4: flp4));
162
163	err = fib_rules_lookup(net->ipv4.mr_rules_ops,
164	flowi4_to_flowi(fl4: flp4), flags: 0, &arg);
165	if (err < 0)
166	return err;
167	*mrt = res.mrt;
168	return 0;
169	}
170
171	static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
172	int flags, struct fib_lookup_arg *arg)
173	{
174	struct ipmr_result *res = arg->result;
175	struct mr_table *mrt;
176
177	switch (rule->action) {
178	case FR_ACT_TO_TBL:
179	break;
180	case FR_ACT_UNREACHABLE:
181	return -ENETUNREACH;
182	case FR_ACT_PROHIBIT:
183	return -EACCES;
184	case FR_ACT_BLACKHOLE:
185	default:
186	return -EINVAL;
187	}
188
189	arg->table = fib_rule_get_table(rule, arg);
190
191	mrt = ipmr_get_table(net: rule->fr_net, id: arg->table);
192	if (!mrt)
193	return -EAGAIN;
194	res->mrt = mrt;
195	return 0;
196	}
197
198	static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
199	{
200	return 1;
201	}
202
203	static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
204	struct fib_rule_hdr *frh, struct nlattr **tb,
205	struct netlink_ext_ack *extack)
206	{
207	return 0;
208	}
209
210	static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
211	struct nlattr **tb)
212	{
213	return 1;
214	}
215
216	static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
217	struct fib_rule_hdr *frh)
218	{
219	frh->dst_len = 0;
220	frh->src_len = 0;
221	frh->tos = 0;
222	return 0;
223	}
224
225	static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
226	.family = RTNL_FAMILY_IPMR,
227	.rule_size = sizeof(struct ipmr_rule),
228	.addr_size = sizeof(u32),
229	.action = ipmr_rule_action,
230	.match = ipmr_rule_match,
231	.configure = ipmr_rule_configure,
232	.compare = ipmr_rule_compare,
233	.fill = ipmr_rule_fill,
234	.nlgroup = RTNLGRP_IPV4_RULE,
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(ptr: ops))
246	return PTR_ERR(ptr: ops);
247
248	INIT_LIST_HEAD(list: &net->ipv4.mr_tables);
249
250	mrt = ipmr_new_table(net, id: RT_TABLE_DEFAULT);
251	if (IS_ERR(ptr: mrt)) {
252	err = PTR_ERR(ptr: mrt);
253	goto err1;
254	}
255
256	err = fib_default_rule_add(ops, pref: 0x7fff, table: RT_TABLE_DEFAULT);
257	if (err < 0)
258	goto err2;
259
260	net->ipv4.mr_rules_ops = ops;
261	return 0;
262
263	err2:
264	rtnl_lock();
265	ipmr_free_table(mrt);
266	rtnl_unlock();
267	err1:
268	fib_rules_unregister(ops);
269	return err;
270	}
271
272	static void __net_exit ipmr_rules_exit(struct net *net)
273	{
274	struct mr_table *mrt, *next;
275
276	ASSERT_RTNL();
277	list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
278	list_del(entry: &mrt->list);
279	ipmr_free_table(mrt);
280	}
281	fib_rules_unregister(net->ipv4.mr_rules_ops);
282	}
283
284	static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
285	struct netlink_ext_ack *extack)
286	{
287	return fib_rules_dump(net, nb, RTNL_FAMILY_IPMR, extack);
288	}
289
290	static unsigned int ipmr_rules_seq_read(struct net *net)
291	{
292	return fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
293	}
294
295	bool ipmr_rule_default(const struct fib_rule *rule)
296	{
297	return fib_rule_matchall(rule) && rule->table == RT_TABLE_DEFAULT;
298	}
299	EXPORT_SYMBOL(ipmr_rule_default);
300	#else
301	#define ipmr_for_each_table(mrt, net) \
302	for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
303
304	static struct mr_table *ipmr_mr_table_iter(struct net *net,
305	struct mr_table *mrt)
306	{
307	if (!mrt)
308	return net->ipv4.mrt;
309	return NULL;
310	}
311
312	static struct mr_table *ipmr_get_table(struct net *net, u32 id)
313	{
314	return net->ipv4.mrt;
315	}
316
317	static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
318	struct mr_table **mrt)
319	{
320	*mrt = net->ipv4.mrt;
321	return 0;
322	}
323
324	static int __net_init ipmr_rules_init(struct net *net)
325	{
326	struct mr_table *mrt;
327
328	mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
329	if (IS_ERR(mrt))
330	return PTR_ERR(mrt);
331	net->ipv4.mrt = mrt;
332	return 0;
333	}
334
335	static void __net_exit ipmr_rules_exit(struct net *net)
336	{
337	ASSERT_RTNL();
338	ipmr_free_table(net->ipv4.mrt);
339	net->ipv4.mrt = NULL;
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	const struct mfc_cache *c = 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(new: &mrt->list, head: &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(error: -EINVAL);
404
405	mrt = ipmr_get_table(net, id);
406	if (mrt)
407	return mrt;
408
409	return mr_table_alloc(net, id, ops: &ipmr_mr_table_ops,
410	expire_func: ipmr_expire_process, table_set: ipmr_new_table_set);
411	}
412
413	static void ipmr_free_table(struct mr_table *mrt)
414	{
415	timer_shutdown_sync(timer: &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(hlt: &mrt->mfc_hash);
419	kfree(objp: mrt);
420	}
421
422	/* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
423
424	/* Initialize ipmr pimreg/tunnel in_device */
425	static bool ipmr_init_vif_indev(const struct net_device *dev)
426	{
427	struct in_device *in_dev;
428
429	ASSERT_RTNL();
430
431	in_dev = __in_dev_get_rtnl(dev);
432	if (!in_dev)
433	return false;
434	ipv4_devconf_setall(in_dev);
435	neigh_parms_data_state_setall(p: in_dev->arp_parms);
436	IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
437
438	return true;
439	}
440
441	static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
442	{
443	struct net_device *tunnel_dev, *new_dev;
444	struct ip_tunnel_parm p = { };
445	int err;
446
447	tunnel_dev = __dev_get_by_name(net, name: "tunl0");
448	if (!tunnel_dev)
449	goto out;
450
451	p.iph.daddr = v->vifc_rmt_addr.s_addr;
452	p.iph.saddr = v->vifc_lcl_addr.s_addr;
453	p.iph.version = 4;
454	p.iph.ihl = 5;
455	p.iph.protocol = IPPROTO_IPIP;
456	sprintf(buf: p.name, fmt: "dvmrp%d", v->vifc_vifi);
457
458	if (!tunnel_dev->netdev_ops->ndo_tunnel_ctl)
459	goto out;
460	err = tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p,
461	SIOCADDTUNNEL);
462	if (err)
463	goto out;
464
465	new_dev = __dev_get_by_name(net, name: p.name);
466	if (!new_dev)
467	goto out;
468
469	new_dev->flags |= IFF_MULTICAST;
470	if (!ipmr_init_vif_indev(dev: new_dev))
471	goto out_unregister;
472	if (dev_open(dev: new_dev, NULL))
473	goto out_unregister;
474	dev_hold(dev: new_dev);
475	err = dev_set_allmulti(dev: new_dev, inc: 1);
476	if (err) {
477	dev_close(dev: new_dev);
478	tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p,
479	SIOCDELTUNNEL);
480	dev_put(dev: new_dev);
481	new_dev = ERR_PTR(error: err);
482	}
483	return new_dev;
484
485	out_unregister:
486	unregister_netdevice(dev: new_dev);
487	out:
488	return ERR_PTR(error: -ENOBUFS);
489	}
490
491	#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
492	static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
493	{
494	struct net *net = dev_net(dev);
495	struct mr_table *mrt;
496	struct flowi4 fl4 = {
497	.flowi4_oif = dev->ifindex,
498	.flowi4_iif = skb->skb_iif ? : LOOPBACK_IFINDEX,
499	.flowi4_mark = skb->mark,
500	};
501	int err;
502
503	err = ipmr_fib_lookup(net, flp4: &fl4, mrt: &mrt);
504	if (err < 0) {
505	kfree_skb(skb);
506	return err;
507	}
508
509	DEV_STATS_ADD(dev, tx_bytes, skb->len);
510	DEV_STATS_INC(dev, tx_packets);
511	rcu_read_lock();
512
513	/* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */
514	ipmr_cache_report(mrt, pkt: skb, READ_ONCE(mrt->mroute_reg_vif_num),
515	IGMPMSG_WHOLEPKT);
516
517	rcu_read_unlock();
518	kfree_skb(skb);
519	return NETDEV_TX_OK;
520	}
521
522	static int reg_vif_get_iflink(const struct net_device *dev)
523	{
524	return 0;
525	}
526
527	static const struct net_device_ops reg_vif_netdev_ops = {
528	.ndo_start_xmit = reg_vif_xmit,
529	.ndo_get_iflink = reg_vif_get_iflink,
530	};
531
532	static void reg_vif_setup(struct net_device *dev)
533	{
534	dev->type = ARPHRD_PIMREG;
535	dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 8;
536	dev->flags = IFF_NOARP;
537	dev->netdev_ops = &reg_vif_netdev_ops;
538	dev->needs_free_netdev = true;
539	dev->features |= NETIF_F_NETNS_LOCAL;
540	}
541
542	static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
543	{
544	struct net_device *dev;
545	char name[IFNAMSIZ];
546
547	if (mrt->id == RT_TABLE_DEFAULT)
548	sprintf(buf: name, fmt: "pimreg");
549	else
550	sprintf(buf: name, fmt: "pimreg%u", mrt->id);
551
552	dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
553
554	if (!dev)
555	return NULL;
556
557	dev_net_set(dev, net);
558
559	if (register_netdevice(dev)) {
560	free_netdev(dev);
561	return NULL;
562	}
563
564	if (!ipmr_init_vif_indev(dev))
565	goto failure;
566	if (dev_open(dev, NULL))
567	goto failure;
568
569	dev_hold(dev);
570
571	return dev;
572
573	failure:
574	unregister_netdevice(dev);
575	return NULL;
576	}
577
578	/* called with rcu_read_lock() */
579	static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
580	unsigned int pimlen)
581	{
582	struct net_device *reg_dev = NULL;
583	struct iphdr *encap;
584	int vif_num;
585
586	encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
587	/* Check that:
588	* a. packet is really sent to a multicast group
589	* b. packet is not a NULL-REGISTER
590	* c. packet is not truncated
591	*/
592	if (!ipv4_is_multicast(addr: encap->daddr) ||
593	encap->tot_len == 0 ||
594	ntohs(encap->tot_len) + pimlen > skb->len)
595	return 1;
596
597	/* Pairs with WRITE_ONCE() in vif_add()/vid_delete() */
598	vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
599	if (vif_num >= 0)
600	reg_dev = vif_dev_read(vif: &mrt->vif_table[vif_num]);
601	if (!reg_dev)
602	return 1;
603
604	skb->mac_header = skb->network_header;
605	skb_pull(skb, len: (u8 *)encap - skb->data);
606	skb_reset_network_header(skb);
607	skb->protocol = htons(ETH_P_IP);
608	skb->ip_summed = CHECKSUM_NONE;
609
610	skb_tunnel_rx(skb, dev: reg_dev, net: dev_net(dev: reg_dev));
611
612	netif_rx(skb);
613
614	return NET_RX_SUCCESS;
615	}
616	#else
617	static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
618	{
619	return NULL;
620	}
621	#endif
622
623	static int call_ipmr_vif_entry_notifiers(struct net *net,
624	enum fib_event_type event_type,
625	struct vif_device *vif,
626	struct net_device *vif_dev,
627	vifi_t vif_index, u32 tb_id)
628	{
629	return mr_call_vif_notifiers(net, RTNL_FAMILY_IPMR, event_type,
630	vif, vif_dev, vif_index, tb_id,
631	ipmr_seq: &net->ipv4.ipmr_seq);
632	}
633
634	static int call_ipmr_mfc_entry_notifiers(struct net *net,
635	enum fib_event_type event_type,
636	struct mfc_cache *mfc, u32 tb_id)
637	{
638	return mr_call_mfc_notifiers(net, RTNL_FAMILY_IPMR, event_type,
639	mfc: &mfc->_c, tb_id, ipmr_seq: &net->ipv4.ipmr_seq);
640	}
641
642	/**
643	* vif_delete - Delete a VIF entry
644	* @mrt: Table to delete from
645	* @vifi: VIF identifier to delete
646	* @notify: Set to 1, if the caller is a notifier_call
647	* @head: if unregistering the VIF, place it on this queue
648	*/
649	static int vif_delete(struct mr_table *mrt, int vifi, int notify,
650	struct list_head *head)
651	{
652	struct net *net = read_pnet(pnet: &mrt->net);
653	struct vif_device *v;
654	struct net_device *dev;
655	struct in_device *in_dev;
656
657	if (vifi < 0 || vifi >= mrt->maxvif)
658	return -EADDRNOTAVAIL;
659
660	v = &mrt->vif_table[vifi];
661
662	dev = rtnl_dereference(v->dev);
663	if (!dev)
664	return -EADDRNOTAVAIL;
665
666	spin_lock(lock: &mrt_lock);
667	call_ipmr_vif_entry_notifiers(net, event_type: FIB_EVENT_VIF_DEL, vif: v, vif_dev: dev,
668	vif_index: vifi, tb_id: mrt->id);
669	RCU_INIT_POINTER(v->dev, NULL);
670
671	if (vifi == mrt->mroute_reg_vif_num) {
672	/* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */
673	WRITE_ONCE(mrt->mroute_reg_vif_num, -1);
674	}
675	if (vifi + 1 == mrt->maxvif) {
676	int tmp;
677
678	for (tmp = vifi - 1; tmp >= 0; tmp--) {
679	if (VIF_EXISTS(mrt, tmp))
680	break;
681	}
682	WRITE_ONCE(mrt->maxvif, tmp + 1);
683	}
684
685	spin_unlock(lock: &mrt_lock);
686
687	dev_set_allmulti(dev, inc: -1);
688
689	in_dev = __in_dev_get_rtnl(dev);
690	if (in_dev) {
691	IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
692	inet_netconf_notify_devconf(net: dev_net(dev), RTM_NEWNETCONF,
693	type: NETCONFA_MC_FORWARDING,
694	ifindex: dev->ifindex, devconf: &in_dev->cnf);
695	ip_rt_multicast_event(in_dev);
696	}
697
698	if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
699	unregister_netdevice_queue(dev, head);
700
701	netdev_put(dev, tracker: &v->dev_tracker);
702	return 0;
703	}
704
705	static void ipmr_cache_free_rcu(struct rcu_head *head)
706	{
707	struct mr_mfc *c = container_of(head, struct mr_mfc, rcu);
708
709	kmem_cache_free(s: mrt_cachep, objp: (struct mfc_cache *)c);
710	}
711
712	static void ipmr_cache_free(struct mfc_cache *c)
713	{
714	call_rcu(head: &c->_c.rcu, func: ipmr_cache_free_rcu);
715	}
716
717	/* Destroy an unresolved cache entry, killing queued skbs
718	* and reporting error to netlink readers.
719	*/
720	static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
721	{
722	struct net *net = read_pnet(pnet: &mrt->net);
723	struct sk_buff *skb;
724	struct nlmsgerr *e;
725
726	atomic_dec(v: &mrt->cache_resolve_queue_len);
727
728	while ((skb = skb_dequeue(list: &c->_c.mfc_un.unres.unresolved))) {
729	if (ip_hdr(skb)->version == 0) {
730	struct nlmsghdr *nlh = skb_pull(skb,
731	len: sizeof(struct iphdr));
732	nlh->nlmsg_type = NLMSG_ERROR;
733	nlh->nlmsg_len = nlmsg_msg_size(payload: sizeof(struct nlmsgerr));
734	skb_trim(skb, len: nlh->nlmsg_len);
735	e = nlmsg_data(nlh);
736	e->error = -ETIMEDOUT;
737	memset(&e->msg, 0, sizeof(e->msg));
738
739	rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
740	} else {
741	kfree_skb(skb);
742	}
743	}
744
745	ipmr_cache_free(c);
746	}
747
748	/* Timer process for the unresolved queue. */
749	static void ipmr_expire_process(struct timer_list *t)
750	{
751	struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
752	struct mr_mfc *c, *next;
753	unsigned long expires;
754	unsigned long now;
755
756	if (!spin_trylock(lock: &mfc_unres_lock)) {
757	mod_timer(timer: &mrt->ipmr_expire_timer, expires: jiffies+HZ/10);
758	return;
759	}
760
761	if (list_empty(head: &mrt->mfc_unres_queue))
762	goto out;
763
764	now = jiffies;
765	expires = 10*HZ;
766
767	list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
768	if (time_after(c->mfc_un.unres.expires, now)) {
769	unsigned long interval = c->mfc_un.unres.expires - now;
770	if (interval < expires)
771	expires = interval;
772	continue;
773	}
774
775	list_del(entry: &c->list);
776	mroute_netlink_event(mrt, mfc: (struct mfc_cache *)c, RTM_DELROUTE);
777	ipmr_destroy_unres(mrt, c: (struct mfc_cache *)c);
778	}
779
780	if (!list_empty(head: &mrt->mfc_unres_queue))
781	mod_timer(timer: &mrt->ipmr_expire_timer, expires: jiffies + expires);
782
783	out:
784	spin_unlock(lock: &mfc_unres_lock);
785	}
786
787	/* Fill oifs list. It is called under locked mrt_lock. */
788	static void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
789	unsigned char *ttls)
790	{
791	int vifi;
792
793	cache->mfc_un.res.minvif = MAXVIFS;
794	cache->mfc_un.res.maxvif = 0;
795	memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
796
797	for (vifi = 0; vifi < mrt->maxvif; vifi++) {
798	if (VIF_EXISTS(mrt, vifi) &&
799	ttls[vifi] && ttls[vifi] < 255) {
800	cache->mfc_un.res.ttls[vifi] = ttls[vifi];
801	if (cache->mfc_un.res.minvif > vifi)
802	cache->mfc_un.res.minvif = vifi;
803	if (cache->mfc_un.res.maxvif <= vifi)
804	cache->mfc_un.res.maxvif = vifi + 1;
805	}
806	}
807	cache->mfc_un.res.lastuse = jiffies;
808	}
809
810	static int vif_add(struct net *net, struct mr_table *mrt,
811	struct vifctl *vifc, int mrtsock)
812	{
813	struct netdev_phys_item_id ppid = { };
814	int vifi = vifc->vifc_vifi;
815	struct vif_device *v = &mrt->vif_table[vifi];
816	struct net_device *dev;
817	struct in_device *in_dev;
818	int err;
819
820	/* Is vif busy ? */
821	if (VIF_EXISTS(mrt, vifi))
822	return -EADDRINUSE;
823
824	switch (vifc->vifc_flags) {
825	case VIFF_REGISTER:
826	if (!ipmr_pimsm_enabled())
827	return -EINVAL;
828	/* Special Purpose VIF in PIM
829	* All the packets will be sent to the daemon
830	*/
831	if (mrt->mroute_reg_vif_num >= 0)
832	return -EADDRINUSE;
833	dev = ipmr_reg_vif(net, mrt);
834	if (!dev)
835	return -ENOBUFS;
836	err = dev_set_allmulti(dev, inc: 1);
837	if (err) {
838	unregister_netdevice(dev);
839	dev_put(dev);
840	return err;
841	}
842	break;
843	case VIFF_TUNNEL:
844	dev = ipmr_new_tunnel(net, v: vifc);
845	if (IS_ERR(ptr: dev))
846	return PTR_ERR(ptr: dev);
847	break;
848	case VIFF_USE_IFINDEX:
849	case 0:
850	if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
851	dev = dev_get_by_index(net, ifindex: vifc->vifc_lcl_ifindex);
852	if (dev && !__in_dev_get_rtnl(dev)) {
853	dev_put(dev);
854	return -EADDRNOTAVAIL;
855	}
856	} else {
857	dev = ip_dev_find(net, addr: vifc->vifc_lcl_addr.s_addr);
858	}
859	if (!dev)
860	return -EADDRNOTAVAIL;
861	err = dev_set_allmulti(dev, inc: 1);
862	if (err) {
863	dev_put(dev);
864	return err;
865	}
866	break;
867	default:
868	return -EINVAL;
869	}
870
871	in_dev = __in_dev_get_rtnl(dev);
872	if (!in_dev) {
873	dev_put(dev);
874	return -EADDRNOTAVAIL;
875	}
876	IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
877	inet_netconf_notify_devconf(net, RTM_NEWNETCONF, type: NETCONFA_MC_FORWARDING,
878	ifindex: dev->ifindex, devconf: &in_dev->cnf);
879	ip_rt_multicast_event(in_dev);
880
881	/* Fill in the VIF structures */
882	vif_device_init(v, dev, rate_limit: vifc->vifc_rate_limit,
883	threshold: vifc->vifc_threshold,
884	flags: vifc->vifc_flags | (!mrtsock ? VIFF_STATIC : 0),
885	get_iflink_mask: (VIFF_TUNNEL | VIFF_REGISTER));
886
887	err = dev_get_port_parent_id(dev, ppid: &ppid, recurse: true);
888	if (err == 0) {
889	memcpy(v->dev_parent_id.id, ppid.id, ppid.id_len);
890	v->dev_parent_id.id_len = ppid.id_len;
891	} else {
892	v->dev_parent_id.id_len = 0;
893	}
894
895	v->local = vifc->vifc_lcl_addr.s_addr;
896	v->remote = vifc->vifc_rmt_addr.s_addr;
897
898	/* And finish update writing critical data */
899	spin_lock(lock: &mrt_lock);
900	rcu_assign_pointer(v->dev, dev);
901	netdev_tracker_alloc(dev, tracker: &v->dev_tracker, GFP_ATOMIC);
902	if (v->flags & VIFF_REGISTER) {
903	/* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */
904	WRITE_ONCE(mrt->mroute_reg_vif_num, vifi);
905	}
906	if (vifi+1 > mrt->maxvif)
907	WRITE_ONCE(mrt->maxvif, vifi + 1);
908	spin_unlock(lock: &mrt_lock);
909	call_ipmr_vif_entry_notifiers(net, event_type: FIB_EVENT_VIF_ADD, vif: v, vif_dev: dev,
910	vif_index: vifi, tb_id: mrt->id);
911	return 0;
912	}
913
914	/* called with rcu_read_lock() */
915	static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
916	__be32 origin,
917	__be32 mcastgrp)
918	{
919	struct mfc_cache_cmp_arg arg = {
920	.mfc_mcastgrp = mcastgrp,
921	.mfc_origin = origin
922	};
923
924	return mr_mfc_find(mrt, hasharg: &arg);
925	}
926
927	/* Look for a (*,G) entry */
928	static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
929	__be32 mcastgrp, int vifi)
930	{
931	struct mfc_cache_cmp_arg arg = {
932	.mfc_mcastgrp = mcastgrp,
933	.mfc_origin = htonl(INADDR_ANY)
934	};
935
936	if (mcastgrp == htonl(INADDR_ANY))
937	return mr_mfc_find_any_parent(mrt, vifi);
938	return mr_mfc_find_any(mrt, vifi, hasharg: &arg);
939	}
940
941	/* Look for a (S,G,iif) entry if parent != -1 */
942	static struct mfc_cache *ipmr_cache_find_parent(struct mr_table *mrt,
943	__be32 origin, __be32 mcastgrp,
944	int parent)
945	{
946	struct mfc_cache_cmp_arg arg = {
947	.mfc_mcastgrp = mcastgrp,
948	.mfc_origin = origin,
949	};
950
951	return mr_mfc_find_parent(mrt, hasharg: &arg, parent);
952	}
953
954	/* Allocate a multicast cache entry */
955	static struct mfc_cache *ipmr_cache_alloc(void)
956	{
957	struct mfc_cache *c = kmem_cache_zalloc(k: mrt_cachep, GFP_KERNEL);
958
959	if (c) {
960	c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
961	c->_c.mfc_un.res.minvif = MAXVIFS;
962	c->_c.free = ipmr_cache_free_rcu;
963	refcount_set(r: &c->_c.mfc_un.res.refcount, n: 1);
964	}
965	return c;
966	}
967
968	static struct mfc_cache *ipmr_cache_alloc_unres(void)
969	{
970	struct mfc_cache *c = kmem_cache_zalloc(k: mrt_cachep, GFP_ATOMIC);
971
972	if (c) {
973	skb_queue_head_init(list: &c->_c.mfc_un.unres.unresolved);
974	c->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
975	}
976	return c;
977	}
978
979	/* A cache entry has gone into a resolved state from queued */
980	static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
981	struct mfc_cache *uc, struct mfc_cache *c)
982	{
983	struct sk_buff *skb;
984	struct nlmsgerr *e;
985
986	/* Play the pending entries through our router */
987	while ((skb = __skb_dequeue(list: &uc->_c.mfc_un.unres.unresolved))) {
988	if (ip_hdr(skb)->version == 0) {
989	struct nlmsghdr *nlh = skb_pull(skb,
990	len: sizeof(struct iphdr));
991
992	if (mr_fill_mroute(mrt, skb, c: &c->_c,
993	rtm: nlmsg_data(nlh)) > 0) {
994	nlh->nlmsg_len = skb_tail_pointer(skb) -
995	(u8 *)nlh;
996	} else {
997	nlh->nlmsg_type = NLMSG_ERROR;
998	nlh->nlmsg_len = nlmsg_msg_size(payload: sizeof(struct nlmsgerr));
999	skb_trim(skb, len: nlh->nlmsg_len);
1000	e = nlmsg_data(nlh);
1001	e->error = -EMSGSIZE;
1002	memset(&e->msg, 0, sizeof(e->msg));
1003	}
1004
1005	rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
1006	} else {
1007	rcu_read_lock();
1008	ip_mr_forward(net, mrt, dev: skb->dev, skb, cache: c, local: 0);
1009	rcu_read_unlock();
1010	}
1011	}
1012	}
1013
1014	/* Bounce a cache query up to mrouted and netlink.
1015	*
1016	* Called under rcu_read_lock().
1017	*/
1018	static int ipmr_cache_report(const struct mr_table *mrt,
1019	struct sk_buff *pkt, vifi_t vifi, int assert)
1020	{
1021	const int ihl = ip_hdrlen(skb: pkt);
1022	struct sock *mroute_sk;
1023	struct igmphdr *igmp;
1024	struct igmpmsg *msg;
1025	struct sk_buff *skb;
1026	int ret;
1027
1028	mroute_sk = rcu_dereference(mrt->mroute_sk);
1029	if (!mroute_sk)
1030	return -EINVAL;
1031
1032	if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE)
1033	skb = skb_realloc_headroom(skb: pkt, headroom: sizeof(struct iphdr));
1034	else
1035	skb = alloc_skb(size: 128, GFP_ATOMIC);
1036
1037	if (!skb)
1038	return -ENOBUFS;
1039
1040	if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) {
1041	/* Ugly, but we have no choice with this interface.
1042	* Duplicate old header, fix ihl, length etc.
1043	* And all this only to mangle msg->im_msgtype and
1044	* to set msg->im_mbz to "mbz" :-)
1045	*/
1046	skb_push(skb, len: sizeof(struct iphdr));
1047	skb_reset_network_header(skb);
1048	skb_reset_transport_header(skb);
1049	msg = (struct igmpmsg *)skb_network_header(skb);
1050	memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
1051	msg->im_msgtype = assert;
1052	msg->im_mbz = 0;
1053	if (assert == IGMPMSG_WRVIFWHOLE) {
1054	msg->im_vif = vifi;
1055	msg->im_vif_hi = vifi >> 8;
1056	} else {
1057	/* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */
1058	int vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
1059
1060	msg->im_vif = vif_num;
1061	msg->im_vif_hi = vif_num >> 8;
1062	}
1063	ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
1064	ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
1065	sizeof(struct iphdr));
1066	} else {
1067	/* Copy the IP header */
1068	skb_set_network_header(skb, offset: skb->len);
1069	skb_put(skb, len: ihl);
1070	skb_copy_to_linear_data(skb, from: pkt->data, len: ihl);
1071	/* Flag to the kernel this is a route add */
1072	ip_hdr(skb)->protocol = 0;
1073	msg = (struct igmpmsg *)skb_network_header(skb);
1074	msg->im_vif = vifi;
1075	msg->im_vif_hi = vifi >> 8;
1076	ipv4_pktinfo_prepare(sk: mroute_sk, skb: pkt, drop_dst: false);
1077	memcpy(skb->cb, pkt->cb, sizeof(skb->cb));
1078	/* Add our header */
1079	igmp = skb_put(skb, len: sizeof(struct igmphdr));
1080	igmp->type = assert;
1081	msg->im_msgtype = assert;
1082	igmp->code = 0;
1083	ip_hdr(skb)->tot_len = htons(skb->len); /* Fix the length */
1084	skb->transport_header = skb->network_header;
1085	}
1086
1087	igmpmsg_netlink_event(mrt, pkt: skb);
1088
1089	/* Deliver to mrouted */
1090	ret = sock_queue_rcv_skb(sk: mroute_sk, skb);
1091
1092	if (ret < 0) {
1093	net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1094	kfree_skb(skb);
1095	}
1096
1097	return ret;
1098	}
1099
1100	/* Queue a packet for resolution. It gets locked cache entry! */
1101	/* Called under rcu_read_lock() */
1102	static int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi,
1103	struct sk_buff *skb, struct net_device *dev)
1104	{
1105	const struct iphdr *iph = ip_hdr(skb);
1106	struct mfc_cache *c;
1107	bool found = false;
1108	int err;
1109
1110	spin_lock_bh(lock: &mfc_unres_lock);
1111	list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
1112	if (c->mfc_mcastgrp == iph->daddr &&
1113	c->mfc_origin == iph->saddr) {
1114	found = true;
1115	break;
1116	}
1117	}
1118
1119	if (!found) {
1120	/* Create a new entry if allowable */
1121	c = ipmr_cache_alloc_unres();
1122	if (!c) {
1123	spin_unlock_bh(lock: &mfc_unres_lock);
1124
1125	kfree_skb(skb);
1126	return -ENOBUFS;
1127	}
1128
1129	/* Fill in the new cache entry */
1130	c->_c.mfc_parent = -1;
1131	c->mfc_origin = iph->saddr;
1132	c->mfc_mcastgrp = iph->daddr;
1133
1134	/* Reflect first query at mrouted. */
1135	err = ipmr_cache_report(mrt, pkt: skb, vifi, IGMPMSG_NOCACHE);
1136
1137	if (err < 0) {
1138	/* If the report failed throw the cache entry
1139	out - Brad Parker
1140	*/
1141	spin_unlock_bh(lock: &mfc_unres_lock);
1142
1143	ipmr_cache_free(c);
1144	kfree_skb(skb);
1145	return err;
1146	}
1147
1148	atomic_inc(v: &mrt->cache_resolve_queue_len);
1149	list_add(new: &c->_c.list, head: &mrt->mfc_unres_queue);
1150	mroute_netlink_event(mrt, mfc: c, RTM_NEWROUTE);
1151
1152	if (atomic_read(v: &mrt->cache_resolve_queue_len) == 1)
1153	mod_timer(timer: &mrt->ipmr_expire_timer,
1154	expires: c->_c.mfc_un.unres.expires);
1155	}
1156
1157	/* See if we can append the packet */
1158	if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
1159	kfree_skb(skb);
1160	err = -ENOBUFS;
1161	} else {
1162	if (dev) {
1163	skb->dev = dev;
1164	skb->skb_iif = dev->ifindex;
1165	}
1166	skb_queue_tail(list: &c->_c.mfc_un.unres.unresolved, newsk: skb);
1167	err = 0;
1168	}
1169
1170	spin_unlock_bh(lock: &mfc_unres_lock);
1171	return err;
1172	}
1173
1174	/* MFC cache manipulation by user space mroute daemon */
1175
1176	static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1177	{
1178	struct net *net = read_pnet(pnet: &mrt->net);
1179	struct mfc_cache *c;
1180
1181	/* The entries are added/deleted only under RTNL */
1182	rcu_read_lock();
1183	c = ipmr_cache_find_parent(mrt, origin: mfc->mfcc_origin.s_addr,
1184	mcastgrp: mfc->mfcc_mcastgrp.s_addr, parent);
1185	rcu_read_unlock();
1186	if (!c)
1187	return -ENOENT;
1188	rhltable_remove(hlt: &mrt->mfc_hash, list: &c->_c.mnode, params: ipmr_rht_params);
1189	list_del_rcu(entry: &c->_c.list);
1190	call_ipmr_mfc_entry_notifiers(net, event_type: FIB_EVENT_ENTRY_DEL, mfc: c, tb_id: mrt->id);
1191	mroute_netlink_event(mrt, mfc: c, RTM_DELROUTE);
1192	mr_cache_put(c: &c->_c);
1193
1194	return 0;
1195	}
1196
1197	static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1198	struct mfcctl *mfc, int mrtsock, int parent)
1199	{
1200	struct mfc_cache *uc, *c;
1201	struct mr_mfc *_uc;
1202	bool found;
1203	int ret;
1204
1205	if (mfc->mfcc_parent >= MAXVIFS)
1206	return -ENFILE;
1207
1208	/* The entries are added/deleted only under RTNL */
1209	rcu_read_lock();
1210	c = ipmr_cache_find_parent(mrt, origin: mfc->mfcc_origin.s_addr,
1211	mcastgrp: mfc->mfcc_mcastgrp.s_addr, parent);
1212	rcu_read_unlock();
1213	if (c) {
1214	spin_lock(lock: &mrt_lock);
1215	c->_c.mfc_parent = mfc->mfcc_parent;
1216	ipmr_update_thresholds(mrt, cache: &c->_c, ttls: mfc->mfcc_ttls);
1217	if (!mrtsock)
1218	c->_c.mfc_flags |= MFC_STATIC;
1219	spin_unlock(lock: &mrt_lock);
1220	call_ipmr_mfc_entry_notifiers(net, event_type: FIB_EVENT_ENTRY_REPLACE, mfc: c,
1221	tb_id: mrt->id);
1222	mroute_netlink_event(mrt, mfc: c, RTM_NEWROUTE);
1223	return 0;
1224	}
1225
1226	if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1227	!ipv4_is_multicast(addr: mfc->mfcc_mcastgrp.s_addr))
1228	return -EINVAL;
1229
1230	c = ipmr_cache_alloc();
1231	if (!c)
1232	return -ENOMEM;
1233
1234	c->mfc_origin = mfc->mfcc_origin.s_addr;
1235	c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1236	c->_c.mfc_parent = mfc->mfcc_parent;
1237	ipmr_update_thresholds(mrt, cache: &c->_c, ttls: mfc->mfcc_ttls);
1238	if (!mrtsock)
1239	c->_c.mfc_flags |= MFC_STATIC;
1240
1241	ret = rhltable_insert_key(hlt: &mrt->mfc_hash, key: &c->cmparg, list: &c->_c.mnode,
1242	params: ipmr_rht_params);
1243	if (ret) {
1244	pr_err("ipmr: rhtable insert error %d\n", ret);
1245	ipmr_cache_free(c);
1246	return ret;
1247	}
1248	list_add_tail_rcu(new: &c->_c.list, head: &mrt->mfc_cache_list);
1249	/* Check to see if we resolved a queued list. If so we
1250	* need to send on the frames and tidy up.
1251	*/
1252	found = false;
1253	spin_lock_bh(lock: &mfc_unres_lock);
1254	list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
1255	uc = (struct mfc_cache *)_uc;
1256	if (uc->mfc_origin == c->mfc_origin &&
1257	uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1258	list_del(entry: &_uc->list);
1259	atomic_dec(v: &mrt->cache_resolve_queue_len);
1260	found = true;
1261	break;
1262	}
1263	}
1264	if (list_empty(head: &mrt->mfc_unres_queue))
1265	del_timer(timer: &mrt->ipmr_expire_timer);
1266	spin_unlock_bh(lock: &mfc_unres_lock);
1267
1268	if (found) {
1269	ipmr_cache_resolve(net, mrt, uc, c);
1270	ipmr_cache_free(c: uc);
1271	}
1272	call_ipmr_mfc_entry_notifiers(net, event_type: FIB_EVENT_ENTRY_ADD, mfc: c, tb_id: mrt->id);
1273	mroute_netlink_event(mrt, mfc: c, RTM_NEWROUTE);
1274	return 0;
1275	}
1276
1277	/* Close the multicast socket, and clear the vif tables etc */
1278	static void mroute_clean_tables(struct mr_table *mrt, int flags)
1279	{
1280	struct net *net = read_pnet(pnet: &mrt->net);
1281	struct mr_mfc *c, *tmp;
1282	struct mfc_cache *cache;
1283	LIST_HEAD(list);
1284	int i;
1285
1286	/* Shut down all active vif entries */
1287	if (flags & (MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC)) {
1288	for (i = 0; i < mrt->maxvif; i++) {
1289	if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
1290	!(flags & MRT_FLUSH_VIFS_STATIC)) ||
1291	(!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT_FLUSH_VIFS)))
1292	continue;
1293	vif_delete(mrt, vifi: i, notify: 0, head: &list);
1294	}
1295	unregister_netdevice_many(head: &list);
1296	}
1297
1298	/* Wipe the cache */
1299	if (flags & (MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC)) {
1300	list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
1301	if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC_STATIC)) ||
1302	(!(c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC)))
1303	continue;
1304	rhltable_remove(hlt: &mrt->mfc_hash, list: &c->mnode, params: ipmr_rht_params);
1305	list_del_rcu(entry: &c->list);
1306	cache = (struct mfc_cache *)c;
1307	call_ipmr_mfc_entry_notifiers(net, event_type: FIB_EVENT_ENTRY_DEL, mfc: cache,
1308	tb_id: mrt->id);
1309	mroute_netlink_event(mrt, mfc: cache, RTM_DELROUTE);
1310	mr_cache_put(c);
1311	}
1312	}
1313
1314	if (flags & MRT_FLUSH_MFC) {
1315	if (atomic_read(v: &mrt->cache_resolve_queue_len) != 0) {
1316	spin_lock_bh(lock: &mfc_unres_lock);
1317	list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
1318	list_del(entry: &c->list);
1319	cache = (struct mfc_cache *)c;
1320	mroute_netlink_event(mrt, mfc: cache, RTM_DELROUTE);
1321	ipmr_destroy_unres(mrt, c: cache);
1322	}
1323	spin_unlock_bh(lock: &mfc_unres_lock);
1324	}
1325	}
1326	}
1327
1328	/* called from ip_ra_control(), before an RCU grace period,
1329	* we don't need to call synchronize_rcu() here
1330	*/
1331	static void mrtsock_destruct(struct sock *sk)
1332	{
1333	struct net *net = sock_net(sk);
1334	struct mr_table *mrt;
1335
1336	rtnl_lock();
1337	ipmr_for_each_table(mrt, net) {
1338	if (sk == rtnl_dereference(mrt->mroute_sk)) {
1339	IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1340	inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1341	type: NETCONFA_MC_FORWARDING,
1342	NETCONFA_IFINDEX_ALL,
1343	devconf: net->ipv4.devconf_all);
1344	RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1345	mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_MFC);
1346	}
1347	}
1348	rtnl_unlock();
1349	}
1350
1351	/* Socket options and virtual interface manipulation. The whole
1352	* virtual interface system is a complete heap, but unfortunately
1353	* that's how BSD mrouted happens to think. Maybe one day with a proper
1354	* MOSPF/PIM router set up we can clean this up.
1355	*/
1356
1357	int ip_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval,
1358	unsigned int optlen)
1359	{
1360	struct net *net = sock_net(sk);
1361	int val, ret = 0, parent = 0;
1362	struct mr_table *mrt;
1363	struct vifctl vif;
1364	struct mfcctl mfc;
1365	bool do_wrvifwhole;
1366	u32 uval;
1367
1368	/* There's one exception to the lock - MRT_DONE which needs to unlock */
1369	rtnl_lock();
1370	if (sk->sk_type != SOCK_RAW ||
1371	inet_sk(sk)->inet_num != IPPROTO_IGMP) {
1372	ret = -EOPNOTSUPP;
1373	goto out_unlock;
1374	}
1375
1376	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1377	if (!mrt) {
1378	ret = -ENOENT;
1379	goto out_unlock;
1380	}
1381	if (optname != MRT_INIT) {
1382	if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1383	!ns_capable(ns: net->user_ns, CAP_NET_ADMIN)) {
1384	ret = -EACCES;
1385	goto out_unlock;
1386	}
1387	}
1388
1389	switch (optname) {
1390	case MRT_INIT:
1391	if (optlen != sizeof(int)) {
1392	ret = -EINVAL;
1393	break;
1394	}
1395	if (rtnl_dereference(mrt->mroute_sk)) {
1396	ret = -EADDRINUSE;
1397	break;
1398	}
1399
1400	ret = ip_ra_control(sk, on: 1, destructor: mrtsock_destruct);
1401	if (ret == 0) {
1402	rcu_assign_pointer(mrt->mroute_sk, sk);
1403	IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1404	inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1405	type: NETCONFA_MC_FORWARDING,
1406	NETCONFA_IFINDEX_ALL,
1407	devconf: net->ipv4.devconf_all);
1408	}
1409	break;
1410	case MRT_DONE:
1411	if (sk != rcu_access_pointer(mrt->mroute_sk)) {
1412	ret = -EACCES;
1413	} else {
1414	/* We need to unlock here because mrtsock_destruct takes
1415	* care of rtnl itself and we can't change that due to
1416	* the IP_ROUTER_ALERT setsockopt which runs without it.
1417	*/
1418	rtnl_unlock();
1419	ret = ip_ra_control(sk, on: 0, NULL);
1420	goto out;
1421	}
1422	break;
1423	case MRT_ADD_VIF:
1424	case MRT_DEL_VIF:
1425	if (optlen != sizeof(vif)) {
1426	ret = -EINVAL;
1427	break;
1428	}
1429	if (copy_from_sockptr(dst: &vif, src: optval, size: sizeof(vif))) {
1430	ret = -EFAULT;
1431	break;
1432	}
1433	if (vif.vifc_vifi >= MAXVIFS) {
1434	ret = -ENFILE;
1435	break;
1436	}
1437	if (optname == MRT_ADD_VIF) {
1438	ret = vif_add(net, mrt, vifc: &vif,
1439	mrtsock: sk == rtnl_dereference(mrt->mroute_sk));
1440	} else {
1441	ret = vif_delete(mrt, vifi: vif.vifc_vifi, notify: 0, NULL);
1442	}
1443	break;
1444	/* Manipulate the forwarding caches. These live
1445	* in a sort of kernel/user symbiosis.
1446	*/
1447	case MRT_ADD_MFC:
1448	case MRT_DEL_MFC:
1449	parent = -1;
1450	fallthrough;
1451	case MRT_ADD_MFC_PROXY:
1452	case MRT_DEL_MFC_PROXY:
1453	if (optlen != sizeof(mfc)) {
1454	ret = -EINVAL;
1455	break;
1456	}
1457	if (copy_from_sockptr(dst: &mfc, src: optval, size: sizeof(mfc))) {
1458	ret = -EFAULT;
1459	break;
1460	}
1461	if (parent == 0)
1462	parent = mfc.mfcc_parent;
1463	if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1464	ret = ipmr_mfc_delete(mrt, mfc: &mfc, parent);
1465	else
1466	ret = ipmr_mfc_add(net, mrt, mfc: &mfc,
1467	mrtsock: sk == rtnl_dereference(mrt->mroute_sk),
1468	parent);
1469	break;
1470	case MRT_FLUSH:
1471	if (optlen != sizeof(val)) {
1472	ret = -EINVAL;
1473	break;
1474	}
1475	if (copy_from_sockptr(dst: &val, src: optval, size: sizeof(val))) {
1476	ret = -EFAULT;
1477	break;
1478	}
1479	mroute_clean_tables(mrt, flags: val);
1480	break;
1481	/* Control PIM assert. */
1482	case MRT_ASSERT:
1483	if (optlen != sizeof(val)) {
1484	ret = -EINVAL;
1485	break;
1486	}
1487	if (copy_from_sockptr(dst: &val, src: optval, size: sizeof(val))) {
1488	ret = -EFAULT;
1489	break;
1490	}
1491	mrt->mroute_do_assert = val;
1492	break;
1493	case MRT_PIM:
1494	if (!ipmr_pimsm_enabled()) {
1495	ret = -ENOPROTOOPT;
1496	break;
1497	}
1498	if (optlen != sizeof(val)) {
1499	ret = -EINVAL;
1500	break;
1501	}
1502	if (copy_from_sockptr(dst: &val, src: optval, size: sizeof(val))) {
1503	ret = -EFAULT;
1504	break;
1505	}
1506
1507	do_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE);
1508	val = !!val;
1509	if (val != mrt->mroute_do_pim) {
1510	mrt->mroute_do_pim = val;
1511	mrt->mroute_do_assert = val;
1512	mrt->mroute_do_wrvifwhole = do_wrvifwhole;
1513	}
1514	break;
1515	case MRT_TABLE:
1516	if (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) {
1517	ret = -ENOPROTOOPT;
1518	break;
1519	}
1520	if (optlen != sizeof(uval)) {
1521	ret = -EINVAL;
1522	break;
1523	}
1524	if (copy_from_sockptr(dst: &uval, src: optval, size: sizeof(uval))) {
1525	ret = -EFAULT;
1526	break;
1527	}
1528
1529	if (sk == rtnl_dereference(mrt->mroute_sk)) {
1530	ret = -EBUSY;
1531	} else {
1532	mrt = ipmr_new_table(net, id: uval);
1533	if (IS_ERR(ptr: mrt))
1534	ret = PTR_ERR(ptr: mrt);
1535	else
1536	raw_sk(sk)->ipmr_table = uval;
1537	}
1538	break;
1539	/* Spurious command, or MRT_VERSION which you cannot set. */
1540	default:
1541	ret = -ENOPROTOOPT;
1542	}
1543	out_unlock:
1544	rtnl_unlock();
1545	out:
1546	return ret;
1547	}
1548
1549	/* Execute if this ioctl is a special mroute ioctl */
1550	int ipmr_sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1551	{
1552	switch (cmd) {
1553	/* These userspace buffers will be consumed by ipmr_ioctl() */
1554	case SIOCGETVIFCNT: {
1555	struct sioc_vif_req buffer;
1556
1557	return sock_ioctl_inout(sk, cmd, arg, karg: &buffer,
1558	size: sizeof(buffer));
1559	}
1560	case SIOCGETSGCNT: {
1561	struct sioc_sg_req buffer;
1562
1563	return sock_ioctl_inout(sk, cmd, arg, karg: &buffer,
1564	size: sizeof(buffer));
1565	}
1566	}
1567	/* return code > 0 means that the ioctl was not executed */
1568	return 1;
1569	}
1570
1571	/* Getsock opt support for the multicast routing system. */
1572	int ip_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval,
1573	sockptr_t optlen)
1574	{
1575	int olr;
1576	int val;
1577	struct net *net = sock_net(sk);
1578	struct mr_table *mrt;
1579
1580	if (sk->sk_type != SOCK_RAW ||
1581	inet_sk(sk)->inet_num != IPPROTO_IGMP)
1582	return -EOPNOTSUPP;
1583
1584	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1585	if (!mrt)
1586	return -ENOENT;
1587
1588	switch (optname) {
1589	case MRT_VERSION:
1590	val = 0x0305;
1591	break;
1592	case MRT_PIM:
1593	if (!ipmr_pimsm_enabled())
1594	return -ENOPROTOOPT;
1595	val = mrt->mroute_do_pim;
1596	break;
1597	case MRT_ASSERT:
1598	val = mrt->mroute_do_assert;
1599	break;
1600	default:
1601	return -ENOPROTOOPT;
1602	}
1603
1604	if (copy_from_sockptr(dst: &olr, src: optlen, size: sizeof(int)))
1605	return -EFAULT;
1606	if (olr < 0)
1607	return -EINVAL;
1608
1609	olr = min_t(unsigned int, olr, sizeof(int));
1610
1611	if (copy_to_sockptr(dst: optlen, src: &olr, size: sizeof(int)))
1612	return -EFAULT;
1613	if (copy_to_sockptr(dst: optval, src: &val, size: olr))
1614	return -EFAULT;
1615	return 0;
1616	}
1617
1618	/* The IP multicast ioctl support routines. */
1619	int ipmr_ioctl(struct sock *sk, int cmd, void *arg)
1620	{
1621	struct vif_device *vif;
1622	struct mfc_cache *c;
1623	struct net *net = sock_net(sk);
1624	struct sioc_vif_req *vr;
1625	struct sioc_sg_req *sr;
1626	struct mr_table *mrt;
1627
1628	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1629	if (!mrt)
1630	return -ENOENT;
1631
1632	switch (cmd) {
1633	case SIOCGETVIFCNT:
1634	vr = (struct sioc_vif_req *)arg;
1635	if (vr->vifi >= mrt->maxvif)
1636	return -EINVAL;
1637	vr->vifi = array_index_nospec(vr->vifi, mrt->maxvif);
1638	rcu_read_lock();
1639	vif = &mrt->vif_table[vr->vifi];
1640	if (VIF_EXISTS(mrt, vr->vifi)) {
1641	vr->icount = READ_ONCE(vif->pkt_in);
1642	vr->ocount = READ_ONCE(vif->pkt_out);
1643	vr->ibytes = READ_ONCE(vif->bytes_in);
1644	vr->obytes = READ_ONCE(vif->bytes_out);
1645	rcu_read_unlock();
1646
1647	return 0;
1648	}
1649	rcu_read_unlock();
1650	return -EADDRNOTAVAIL;
1651	case SIOCGETSGCNT:
1652	sr = (struct sioc_sg_req *)arg;
1653
1654	rcu_read_lock();
1655	c = ipmr_cache_find(mrt, origin: sr->src.s_addr, mcastgrp: sr->grp.s_addr);
1656	if (c) {
1657	sr->pktcnt = c->_c.mfc_un.res.pkt;
1658	sr->bytecnt = c->_c.mfc_un.res.bytes;
1659	sr->wrong_if = c->_c.mfc_un.res.wrong_if;
1660	rcu_read_unlock();
1661	return 0;
1662	}
1663	rcu_read_unlock();
1664	return -EADDRNOTAVAIL;
1665	default:
1666	return -ENOIOCTLCMD;
1667	}
1668	}
1669
1670	#ifdef CONFIG_COMPAT
1671	struct compat_sioc_sg_req {
1672	struct in_addr src;
1673	struct in_addr grp;
1674	compat_ulong_t pktcnt;
1675	compat_ulong_t bytecnt;
1676	compat_ulong_t wrong_if;
1677	};
1678
1679	struct compat_sioc_vif_req {
1680	vifi_t vifi; /* Which iface */
1681	compat_ulong_t icount;
1682	compat_ulong_t ocount;
1683	compat_ulong_t ibytes;
1684	compat_ulong_t obytes;
1685	};
1686
1687	int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1688	{
1689	struct compat_sioc_sg_req sr;
1690	struct compat_sioc_vif_req vr;
1691	struct vif_device *vif;
1692	struct mfc_cache *c;
1693	struct net *net = sock_net(sk);
1694	struct mr_table *mrt;
1695
1696	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1697	if (!mrt)
1698	return -ENOENT;
1699
1700	switch (cmd) {
1701	case SIOCGETVIFCNT:
1702	if (copy_from_user(to: &vr, from: arg, n: sizeof(vr)))
1703	return -EFAULT;
1704	if (vr.vifi >= mrt->maxvif)
1705	return -EINVAL;
1706	vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
1707	rcu_read_lock();
1708	vif = &mrt->vif_table[vr.vifi];
1709	if (VIF_EXISTS(mrt, vr.vifi)) {
1710	vr.icount = READ_ONCE(vif->pkt_in);
1711	vr.ocount = READ_ONCE(vif->pkt_out);
1712	vr.ibytes = READ_ONCE(vif->bytes_in);
1713	vr.obytes = READ_ONCE(vif->bytes_out);
1714	rcu_read_unlock();
1715
1716	if (copy_to_user(to: arg, from: &vr, n: sizeof(vr)))
1717	return -EFAULT;
1718	return 0;
1719	}
1720	rcu_read_unlock();
1721	return -EADDRNOTAVAIL;
1722	case SIOCGETSGCNT:
1723	if (copy_from_user(to: &sr, from: arg, n: sizeof(sr)))
1724	return -EFAULT;
1725
1726	rcu_read_lock();
1727	c = ipmr_cache_find(mrt, origin: sr.src.s_addr, mcastgrp: sr.grp.s_addr);
1728	if (c) {
1729	sr.pktcnt = c->_c.mfc_un.res.pkt;
1730	sr.bytecnt = c->_c.mfc_un.res.bytes;
1731	sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1732	rcu_read_unlock();
1733
1734	if (copy_to_user(to: arg, from: &sr, n: sizeof(sr)))
1735	return -EFAULT;
1736	return 0;
1737	}
1738	rcu_read_unlock();
1739	return -EADDRNOTAVAIL;
1740	default:
1741	return -ENOIOCTLCMD;
1742	}
1743	}
1744	#endif
1745
1746	static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1747	{
1748	struct net_device *dev = netdev_notifier_info_to_dev(info: ptr);
1749	struct net *net = dev_net(dev);
1750	struct mr_table *mrt;
1751	struct vif_device *v;
1752	int ct;
1753
1754	if (event != NETDEV_UNREGISTER)
1755	return NOTIFY_DONE;
1756
1757	ipmr_for_each_table(mrt, net) {
1758	v = &mrt->vif_table[0];
1759	for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1760	if (rcu_access_pointer(v->dev) == dev)
1761	vif_delete(mrt, vifi: ct, notify: 1, NULL);
1762	}
1763	}
1764	return NOTIFY_DONE;
1765	}
1766
1767	static struct notifier_block ip_mr_notifier = {
1768	.notifier_call = ipmr_device_event,
1769	};
1770
1771	/* Encapsulate a packet by attaching a valid IPIP header to it.
1772	* This avoids tunnel drivers and other mess and gives us the speed so
1773	* important for multicast video.
1774	*/
1775	static void ip_encap(struct net *net, struct sk_buff *skb,
1776	__be32 saddr, __be32 daddr)
1777	{
1778	struct iphdr *iph;
1779	const struct iphdr *old_iph = ip_hdr(skb);
1780
1781	skb_push(skb, len: sizeof(struct iphdr));
1782	skb->transport_header = skb->network_header;
1783	skb_reset_network_header(skb);
1784	iph = ip_hdr(skb);
1785
1786	iph->version = 4;
1787	iph->tos = old_iph->tos;
1788	iph->ttl = old_iph->ttl;
1789	iph->frag_off = 0;
1790	iph->daddr = daddr;
1791	iph->saddr = saddr;
1792	iph->protocol = IPPROTO_IPIP;
1793	iph->ihl = 5;
1794	iph->tot_len = htons(skb->len);
1795	ip_select_ident(net, skb, NULL);
1796	ip_send_check(ip: iph);
1797
1798	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1799	nf_reset_ct(skb);
1800	}
1801
1802	static inline int ipmr_forward_finish(struct net *net, struct sock *sk,
1803	struct sk_buff *skb)
1804	{
1805	struct ip_options *opt = &(IPCB(skb)->opt);
1806
1807	IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
1808
1809	if (unlikely(opt->optlen))
1810	ip_forward_options(skb);
1811
1812	return dst_output(net, sk, skb);
1813	}
1814
1815	#ifdef CONFIG_NET_SWITCHDEV
1816	static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1817	int in_vifi, int out_vifi)
1818	{
1819	struct vif_device *out_vif = &mrt->vif_table[out_vifi];
1820	struct vif_device *in_vif = &mrt->vif_table[in_vifi];
1821
1822	if (!skb->offload_l3_fwd_mark)
1823	return false;
1824	if (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
1825	return false;
1826	return netdev_phys_item_id_same(a: &out_vif->dev_parent_id,
1827	b: &in_vif->dev_parent_id);
1828	}
1829	#else
1830	static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1831	int in_vifi, int out_vifi)
1832	{
1833	return false;
1834	}
1835	#endif
1836
1837	/* Processing handlers for ipmr_forward, under rcu_read_lock() */
1838
1839	static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1840	int in_vifi, struct sk_buff *skb, int vifi)
1841	{
1842	const struct iphdr *iph = ip_hdr(skb);
1843	struct vif_device *vif = &mrt->vif_table[vifi];
1844	struct net_device *vif_dev;
1845	struct net_device *dev;
1846	struct rtable *rt;
1847	struct flowi4 fl4;
1848	int encap = 0;
1849
1850	vif_dev = vif_dev_read(vif);
1851	if (!vif_dev)
1852	goto out_free;
1853
1854	if (vif->flags & VIFF_REGISTER) {
1855	WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1856	WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1857	DEV_STATS_ADD(vif_dev, tx_bytes, skb->len);
1858	DEV_STATS_INC(vif_dev, tx_packets);
1859	ipmr_cache_report(mrt, pkt: skb, vifi, IGMPMSG_WHOLEPKT);
1860	goto out_free;
1861	}
1862
1863	if (ipmr_forward_offloaded(skb, mrt, in_vifi, out_vifi: vifi))
1864	goto out_free;
1865
1866	if (vif->flags & VIFF_TUNNEL) {
1867	rt = ip_route_output_ports(net, fl4: &fl4, NULL,
1868	daddr: vif->remote, saddr: vif->local,
1869	dport: 0, sport: 0,
1870	IPPROTO_IPIP,
1871	RT_TOS(iph->tos), oif: vif->link);
1872	if (IS_ERR(ptr: rt))
1873	goto out_free;
1874	encap = sizeof(struct iphdr);
1875	} else {
1876	rt = ip_route_output_ports(net, fl4: &fl4, NULL, daddr: iph->daddr, saddr: 0,
1877	dport: 0, sport: 0,
1878	IPPROTO_IPIP,
1879	RT_TOS(iph->tos), oif: vif->link);
1880	if (IS_ERR(ptr: rt))
1881	goto out_free;
1882	}
1883
1884	dev = rt->dst.dev;
1885
1886	if (skb->len+encap > dst_mtu(dst: &rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1887	/* Do not fragment multicasts. Alas, IPv4 does not
1888	* allow to send ICMP, so that packets will disappear
1889	* to blackhole.
1890	*/
1891	IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
1892	ip_rt_put(rt);
1893	goto out_free;
1894	}
1895
1896	encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1897
1898	if (skb_cow(skb, headroom: encap)) {
1899	ip_rt_put(rt);
1900	goto out_free;
1901	}
1902
1903	WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1904	WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1905
1906	skb_dst_drop(skb);
1907	skb_dst_set(skb, dst: &rt->dst);
1908	ip_decrease_ttl(iph: ip_hdr(skb));
1909
1910	/* FIXME: forward and output firewalls used to be called here.
1911	* What do we do with netfilter? -- RR
1912	*/
1913	if (vif->flags & VIFF_TUNNEL) {
1914	ip_encap(net, skb, saddr: vif->local, daddr: vif->remote);
1915	/* FIXME: extra output firewall step used to be here. --RR */
1916	DEV_STATS_INC(vif_dev, tx_packets);
1917	DEV_STATS_ADD(vif_dev, tx_bytes, skb->len);
1918	}
1919
1920	IPCB(skb)->flags |= IPSKB_FORWARDED;
1921
1922	/* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1923	* not only before forwarding, but after forwarding on all output
1924	* interfaces. It is clear, if mrouter runs a multicasting
1925	* program, it should receive packets not depending to what interface
1926	* program is joined.
1927	* If we will not make it, the program will have to join on all
1928	* interfaces. On the other hand, multihoming host (or router, but
1929	* not mrouter) cannot join to more than one interface - it will
1930	* result in receiving multiple packets.
1931	*/
1932	NF_HOOK(pf: NFPROTO_IPV4, hook: NF_INET_FORWARD,
1933	net, NULL, skb, in: skb->dev, out: dev,
1934	okfn: ipmr_forward_finish);
1935	return;
1936
1937	out_free:
1938	kfree_skb(skb);
1939	}
1940
1941	/* Called with mrt_lock or rcu_read_lock() */
1942	static int ipmr_find_vif(const struct mr_table *mrt, struct net_device *dev)
1943	{
1944	int ct;
1945	/* Pairs with WRITE_ONCE() in vif_delete()/vif_add() */
1946	for (ct = READ_ONCE(mrt->maxvif) - 1; ct >= 0; ct--) {
1947	if (rcu_access_pointer(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	/* Called uner rcu_read_lock() */
1955	static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1956	struct net_device *dev, struct sk_buff *skb,
1957	struct mfc_cache *c, int local)
1958	{
1959	int true_vifi = ipmr_find_vif(mrt, dev);
1960	int psend = -1;
1961	int vif, ct;
1962
1963	vif = c->_c.mfc_parent;
1964	c->_c.mfc_un.res.pkt++;
1965	c->_c.mfc_un.res.bytes += skb->len;
1966	c->_c.mfc_un.res.lastuse = jiffies;
1967
1968	if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1969	struct mfc_cache *cache_proxy;
1970
1971	/* For an (*,G) entry, we only check that the incoming
1972	* interface is part of the static tree.
1973	*/
1974	cache_proxy = mr_mfc_find_any_parent(mrt, vifi: vif);
1975	if (cache_proxy &&
1976	cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
1977	goto forward;
1978	}
1979
1980	/* Wrong interface: drop packet and (maybe) send PIM assert. */
1981	if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) {
1982	if (rt_is_output_route(rt: skb_rtable(skb))) {
1983	/* It is our own packet, looped back.
1984	* Very complicated situation...
1985	*
1986	* The best workaround until routing daemons will be
1987	* fixed is not to redistribute packet, if it was
1988	* send through wrong interface. It means, that
1989	* multicast applications WILL NOT work for
1990	* (S,G), which have default multicast route pointing
1991	* to wrong oif. In any case, it is not a good
1992	* idea to use multicasting applications on router.
1993	*/
1994	goto dont_forward;
1995	}
1996
1997	c->_c.mfc_un.res.wrong_if++;
1998
1999	if (true_vifi >= 0 && mrt->mroute_do_assert &&
2000	/* pimsm uses asserts, when switching from RPT to SPT,
2001	* so that we cannot check that packet arrived on an oif.
2002	* It is bad, but otherwise we would need to move pretty
2003	* large chunk of pimd to kernel. Ough... --ANK
2004	*/
2005	(mrt->mroute_do_pim ||
2006	c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
2007	time_after(jiffies,
2008	c->_c.mfc_un.res.last_assert +
2009	MFC_ASSERT_THRESH)) {
2010	c->_c.mfc_un.res.last_assert = jiffies;
2011	ipmr_cache_report(mrt, pkt: skb, vifi: true_vifi, IGMPMSG_WRONGVIF);
2012	if (mrt->mroute_do_wrvifwhole)
2013	ipmr_cache_report(mrt, pkt: skb, vifi: true_vifi,
2014	IGMPMSG_WRVIFWHOLE);
2015	}
2016	goto dont_forward;
2017	}
2018
2019	forward:
2020	WRITE_ONCE(mrt->vif_table[vif].pkt_in,
2021	mrt->vif_table[vif].pkt_in + 1);
2022	WRITE_ONCE(mrt->vif_table[vif].bytes_in,
2023	mrt->vif_table[vif].bytes_in + skb->len);
2024
2025	/* Forward the frame */
2026	if (c->mfc_origin == htonl(INADDR_ANY) &&
2027	c->mfc_mcastgrp == htonl(INADDR_ANY)) {
2028	if (true_vifi >= 0 &&
2029	true_vifi != c->_c.mfc_parent &&
2030	ip_hdr(skb)->ttl >
2031	c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
2032	/* It's an (*,*) entry and the packet is not coming from
2033	* the upstream: forward the packet to the upstream
2034	* only.
2035	*/
2036	psend = c->_c.mfc_parent;
2037	goto last_forward;
2038	}
2039	goto dont_forward;
2040	}
2041	for (ct = c->_c.mfc_un.res.maxvif - 1;
2042	ct >= c->_c.mfc_un.res.minvif; ct--) {
2043	/* For (*,G) entry, don't forward to the incoming interface */
2044	if ((c->mfc_origin != htonl(INADDR_ANY) ||
2045	ct != true_vifi) &&
2046	ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) {
2047	if (psend != -1) {
2048	struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2049
2050	if (skb2)
2051	ipmr_queue_xmit(net, mrt, in_vifi: true_vifi,
2052	skb: skb2, vifi: psend);
2053	}
2054	psend = ct;
2055	}
2056	}
2057	last_forward:
2058	if (psend != -1) {
2059	if (local) {
2060	struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2061
2062	if (skb2)
2063	ipmr_queue_xmit(net, mrt, in_vifi: true_vifi, skb: skb2,
2064	vifi: psend);
2065	} else {
2066	ipmr_queue_xmit(net, mrt, in_vifi: true_vifi, skb, vifi: psend);
2067	return;
2068	}
2069	}
2070
2071	dont_forward:
2072	if (!local)
2073	kfree_skb(skb);
2074	}
2075
2076	static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
2077	{
2078	struct rtable *rt = skb_rtable(skb);
2079	struct iphdr *iph = ip_hdr(skb);
2080	struct flowi4 fl4 = {
2081	.daddr = iph->daddr,
2082	.saddr = iph->saddr,
2083	.flowi4_tos = RT_TOS(iph->tos),
2084	.flowi4_oif = (rt_is_output_route(rt) ?
2085	skb->dev->ifindex : 0),
2086	.flowi4_iif = (rt_is_output_route(rt) ?
2087	LOOPBACK_IFINDEX :
2088	skb->dev->ifindex),
2089	.flowi4_mark = skb->mark,
2090	};
2091	struct mr_table *mrt;
2092	int err;
2093
2094	err = ipmr_fib_lookup(net, flp4: &fl4, mrt: &mrt);
2095	if (err)
2096	return ERR_PTR(error: err);
2097	return mrt;
2098	}
2099
2100	/* Multicast packets for forwarding arrive here
2101	* Called with rcu_read_lock();
2102	*/
2103	int ip_mr_input(struct sk_buff *skb)
2104	{
2105	struct mfc_cache *cache;
2106	struct net *net = dev_net(dev: skb->dev);
2107	int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
2108	struct mr_table *mrt;
2109	struct net_device *dev;
2110
2111	/* skb->dev passed in is the loX master dev for vrfs.
2112	* As there are no vifs associated with loopback devices,
2113	* get the proper interface that does have a vif associated with it.
2114	*/
2115	dev = skb->dev;
2116	if (netif_is_l3_master(dev: skb->dev)) {
2117	dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
2118	if (!dev) {
2119	kfree_skb(skb);
2120	return -ENODEV;
2121	}
2122	}
2123
2124	/* Packet is looped back after forward, it should not be
2125	* forwarded second time, but still can be delivered locally.
2126	*/
2127	if (IPCB(skb)->flags & IPSKB_FORWARDED)
2128	goto dont_forward;
2129
2130	mrt = ipmr_rt_fib_lookup(net, skb);
2131	if (IS_ERR(ptr: mrt)) {
2132	kfree_skb(skb);
2133	return PTR_ERR(ptr: mrt);
2134	}
2135	if (!local) {
2136	if (IPCB(skb)->opt.router_alert) {
2137	if (ip_call_ra_chain(skb))
2138	return 0;
2139	} else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
2140	/* IGMPv1 (and broken IGMPv2 implementations sort of
2141	* Cisco IOS <= 11.2(8)) do not put router alert
2142	* option to IGMP packets destined to routable
2143	* groups. It is very bad, because it means
2144	* that we can forward NO IGMP messages.
2145	*/
2146	struct sock *mroute_sk;
2147
2148	mroute_sk = rcu_dereference(mrt->mroute_sk);
2149	if (mroute_sk) {
2150	nf_reset_ct(skb);
2151	raw_rcv(mroute_sk, skb);
2152	return 0;
2153	}
2154	}
2155	}
2156
2157	/* already under rcu_read_lock() */
2158	cache = ipmr_cache_find(mrt, origin: ip_hdr(skb)->saddr, mcastgrp: ip_hdr(skb)->daddr);
2159	if (!cache) {
2160	int vif = ipmr_find_vif(mrt, dev);
2161
2162	if (vif >= 0)
2163	cache = ipmr_cache_find_any(mrt, mcastgrp: ip_hdr(skb)->daddr,
2164	vifi: vif);
2165	}
2166
2167	/* No usable cache entry */
2168	if (!cache) {
2169	int vif;
2170
2171	if (local) {
2172	struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2173	ip_local_deliver(skb);
2174	if (!skb2)
2175	return -ENOBUFS;
2176	skb = skb2;
2177	}
2178
2179	vif = ipmr_find_vif(mrt, dev);
2180	if (vif >= 0)
2181	return ipmr_cache_unresolved(mrt, vifi: vif, skb, dev);
2182	kfree_skb(skb);
2183	return -ENODEV;
2184	}
2185
2186	ip_mr_forward(net, mrt, dev, skb, c: cache, local);
2187
2188	if (local)
2189	return ip_local_deliver(skb);
2190
2191	return 0;
2192
2193	dont_forward:
2194	if (local)
2195	return ip_local_deliver(skb);
2196	kfree_skb(skb);
2197	return 0;
2198	}
2199
2200	#ifdef CONFIG_IP_PIMSM_V1
2201	/* Handle IGMP messages of PIMv1 */
2202	int pim_rcv_v1(struct sk_buff *skb)
2203	{
2204	struct igmphdr *pim;
2205	struct net *net = dev_net(dev: skb->dev);
2206	struct mr_table *mrt;
2207
2208	if (!pskb_may_pull(skb, len: sizeof(*pim) + sizeof(struct iphdr)))
2209	goto drop;
2210
2211	pim = igmp_hdr(skb);
2212
2213	mrt = ipmr_rt_fib_lookup(net, skb);
2214	if (IS_ERR(ptr: mrt))
2215	goto drop;
2216	if (!mrt->mroute_do_pim ||
2217	pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
2218	goto drop;
2219
2220	if (__pim_rcv(mrt, skb, pimlen: sizeof(*pim))) {
2221	drop:
2222	kfree_skb(skb);
2223	}
2224	return 0;
2225	}
2226	#endif
2227
2228	#ifdef CONFIG_IP_PIMSM_V2
2229	static int pim_rcv(struct sk_buff *skb)
2230	{
2231	struct pimreghdr *pim;
2232	struct net *net = dev_net(dev: skb->dev);
2233	struct mr_table *mrt;
2234
2235	if (!pskb_may_pull(skb, len: sizeof(*pim) + sizeof(struct iphdr)))
2236	goto drop;
2237
2238	pim = (struct pimreghdr *)skb_transport_header(skb);
2239	if (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) ||
2240	(pim->flags & PIM_NULL_REGISTER) ||
2241	(ip_compute_csum(buff: (void *)pim, len: sizeof(*pim)) != 0 &&
2242	csum_fold(sum: skb_checksum(skb, offset: 0, len: skb->len, csum: 0))))
2243	goto drop;
2244
2245	mrt = ipmr_rt_fib_lookup(net, skb);
2246	if (IS_ERR(ptr: mrt))
2247	goto drop;
2248	if (__pim_rcv(mrt, skb, pimlen: sizeof(*pim))) {
2249	drop:
2250	kfree_skb(skb);
2251	}
2252	return 0;
2253	}
2254	#endif
2255
2256	int ipmr_get_route(struct net *net, struct sk_buff *skb,
2257	__be32 saddr, __be32 daddr,
2258	struct rtmsg *rtm, u32 portid)
2259	{
2260	struct mfc_cache *cache;
2261	struct mr_table *mrt;
2262	int err;
2263
2264	mrt = ipmr_get_table(net, id: RT_TABLE_DEFAULT);
2265	if (!mrt)
2266	return -ENOENT;
2267
2268	rcu_read_lock();
2269	cache = ipmr_cache_find(mrt, origin: saddr, mcastgrp: daddr);
2270	if (!cache && skb->dev) {
2271	int vif = ipmr_find_vif(mrt, dev: skb->dev);
2272
2273	if (vif >= 0)
2274	cache = ipmr_cache_find_any(mrt, mcastgrp: daddr, vifi: vif);
2275	}
2276	if (!cache) {
2277	struct sk_buff *skb2;
2278	struct iphdr *iph;
2279	struct net_device *dev;
2280	int vif = -1;
2281
2282	dev = skb->dev;
2283	if (dev)
2284	vif = ipmr_find_vif(mrt, dev);
2285	if (vif < 0) {
2286	rcu_read_unlock();
2287	return -ENODEV;
2288	}
2289
2290	skb2 = skb_realloc_headroom(skb, headroom: sizeof(struct iphdr));
2291	if (!skb2) {
2292	rcu_read_unlock();
2293	return -ENOMEM;
2294	}
2295
2296	NETLINK_CB(skb2).portid = portid;
2297	skb_push(skb: skb2, len: sizeof(struct iphdr));
2298	skb_reset_network_header(skb: skb2);
2299	iph = ip_hdr(skb: skb2);
2300	iph->ihl = sizeof(struct iphdr) >> 2;
2301	iph->saddr = saddr;
2302	iph->daddr = daddr;
2303	iph->version = 0;
2304	err = ipmr_cache_unresolved(mrt, vifi: vif, skb: skb2, dev);
2305	rcu_read_unlock();
2306	return err;
2307	}
2308
2309	err = mr_fill_mroute(mrt, skb, c: &cache->_c, rtm);
2310	rcu_read_unlock();
2311	return err;
2312	}
2313
2314	static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2315	u32 portid, u32 seq, struct mfc_cache *c, int cmd,
2316	int flags)
2317	{
2318	struct nlmsghdr *nlh;
2319	struct rtmsg *rtm;
2320	int err;
2321
2322	nlh = nlmsg_put(skb, portid, seq, type: cmd, payload: sizeof(*rtm), flags);
2323	if (!nlh)
2324	return -EMSGSIZE;
2325
2326	rtm = nlmsg_data(nlh);
2327	rtm->rtm_family = RTNL_FAMILY_IPMR;
2328	rtm->rtm_dst_len = 32;
2329	rtm->rtm_src_len = 32;
2330	rtm->rtm_tos = 0;
2331	rtm->rtm_table = mrt->id;
2332	if (nla_put_u32(skb, attrtype: RTA_TABLE, value: mrt->id))
2333	goto nla_put_failure;
2334	rtm->rtm_type = RTN_MULTICAST;
2335	rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2336	if (c->_c.mfc_flags & MFC_STATIC)
2337	rtm->rtm_protocol = RTPROT_STATIC;
2338	else
2339	rtm->rtm_protocol = RTPROT_MROUTED;
2340	rtm->rtm_flags = 0;
2341
2342	if (nla_put_in_addr(skb, attrtype: RTA_SRC, addr: c->mfc_origin) ||
2343	nla_put_in_addr(skb, attrtype: RTA_DST, addr: c->mfc_mcastgrp))
2344	goto nla_put_failure;
2345	err = mr_fill_mroute(mrt, skb, c: &c->_c, rtm);
2346	/* do not break the dump if cache is unresolved */
2347	if (err < 0 && err != -ENOENT)
2348	goto nla_put_failure;
2349
2350	nlmsg_end(skb, nlh);
2351	return 0;
2352
2353	nla_put_failure:
2354	nlmsg_cancel(skb, nlh);
2355	return -EMSGSIZE;
2356	}
2357
2358	static int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2359	u32 portid, u32 seq, struct mr_mfc *c, int cmd,
2360	int flags)
2361	{
2362	return ipmr_fill_mroute(mrt, skb, portid, seq, c: (struct mfc_cache *)c,
2363	cmd, flags);
2364	}
2365
2366	static size_t mroute_msgsize(bool unresolved, int maxvif)
2367	{
2368	size_t len =
2369	NLMSG_ALIGN(sizeof(struct rtmsg))
2370	+ nla_total_size(payload: 4) /* RTA_TABLE */
2371	+ nla_total_size(payload: 4) /* RTA_SRC */
2372	+ nla_total_size(payload: 4) /* RTA_DST */
2373	;
2374
2375	if (!unresolved)
2376	len = len
2377	+ nla_total_size(payload: 4) /* RTA_IIF */
2378	+ nla_total_size(payload: 0) /* RTA_MULTIPATH */
2379	+ maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2380	/* RTA_MFC_STATS */
2381	+ nla_total_size_64bit(payload: sizeof(struct rta_mfc_stats))
2382	;
2383
2384	return len;
2385	}
2386
2387	static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2388	int cmd)
2389	{
2390	struct net *net = read_pnet(pnet: &mrt->net);
2391	struct sk_buff *skb;
2392	int err = -ENOBUFS;
2393
2394	skb = nlmsg_new(payload: mroute_msgsize(unresolved: mfc->_c.mfc_parent >= MAXVIFS,
2395	maxvif: mrt->maxvif),
2396	GFP_ATOMIC);
2397	if (!skb)
2398	goto errout;
2399
2400	err = ipmr_fill_mroute(mrt, skb, portid: 0, seq: 0, c: mfc, cmd, flags: 0);
2401	if (err < 0)
2402	goto errout;
2403
2404	rtnl_notify(skb, net, pid: 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2405	return;
2406
2407	errout:
2408	kfree_skb(skb);
2409	if (err < 0)
2410	rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, error: err);
2411	}
2412
2413	static size_t igmpmsg_netlink_msgsize(size_t payloadlen)
2414	{
2415	size_t len =
2416	NLMSG_ALIGN(sizeof(struct rtgenmsg))
2417	+ nla_total_size(payload: 1) /* IPMRA_CREPORT_MSGTYPE */
2418	+ nla_total_size(payload: 4) /* IPMRA_CREPORT_VIF_ID */
2419	+ nla_total_size(payload: 4) /* IPMRA_CREPORT_SRC_ADDR */
2420	+ nla_total_size(payload: 4) /* IPMRA_CREPORT_DST_ADDR */
2421	+ nla_total_size(payload: 4) /* IPMRA_CREPORT_TABLE */
2422	/* IPMRA_CREPORT_PKT */
2423	+ nla_total_size(payload: payloadlen)
2424	;
2425
2426	return len;
2427	}
2428
2429	static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt)
2430	{
2431	struct net *net = read_pnet(pnet: &mrt->net);
2432	struct nlmsghdr *nlh;
2433	struct rtgenmsg *rtgenm;
2434	struct igmpmsg *msg;
2435	struct sk_buff *skb;
2436	struct nlattr *nla;
2437	int payloadlen;
2438
2439	payloadlen = pkt->len - sizeof(struct igmpmsg);
2440	msg = (struct igmpmsg *)skb_network_header(skb: pkt);
2441
2442	skb = nlmsg_new(payload: igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2443	if (!skb)
2444	goto errout;
2445
2446	nlh = nlmsg_put(skb, portid: 0, seq: 0, RTM_NEWCACHEREPORT,
2447	payload: sizeof(struct rtgenmsg), flags: 0);
2448	if (!nlh)
2449	goto errout;
2450	rtgenm = nlmsg_data(nlh);
2451	rtgenm->rtgen_family = RTNL_FAMILY_IPMR;
2452	if (nla_put_u8(skb, attrtype: IPMRA_CREPORT_MSGTYPE, value: msg->im_msgtype) ||
2453	nla_put_u32(skb, attrtype: IPMRA_CREPORT_VIF_ID, value: msg->im_vif | (msg->im_vif_hi << 8)) ||
2454	nla_put_in_addr(skb, attrtype: IPMRA_CREPORT_SRC_ADDR,
2455	addr: msg->im_src.s_addr) ||
2456	nla_put_in_addr(skb, attrtype: IPMRA_CREPORT_DST_ADDR,
2457	addr: msg->im_dst.s_addr) ||
2458	nla_put_u32(skb, attrtype: IPMRA_CREPORT_TABLE, value: mrt->id))
2459	goto nla_put_failure;
2460
2461	nla = nla_reserve(skb, attrtype: IPMRA_CREPORT_PKT, attrlen: payloadlen);
2462	if (!nla || skb_copy_bits(skb: pkt, offset: sizeof(struct igmpmsg),
2463	to: nla_data(nla), len: payloadlen))
2464	goto nla_put_failure;
2465
2466	nlmsg_end(skb, nlh);
2467
2468	rtnl_notify(skb, net, pid: 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
2469	return;
2470
2471	nla_put_failure:
2472	nlmsg_cancel(skb, nlh);
2473	errout:
2474	kfree_skb(skb);
2475	rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, error: -ENOBUFS);
2476	}
2477
2478	static int ipmr_rtm_valid_getroute_req(struct sk_buff *skb,
2479	const struct nlmsghdr *nlh,
2480	struct nlattr **tb,
2481	struct netlink_ext_ack *extack)
2482	{
2483	struct rtmsg *rtm;
2484	int i, err;
2485
2486	if (nlh->nlmsg_len < nlmsg_msg_size(payload: sizeof(*rtm))) {
2487	NL_SET_ERR_MSG(extack, "ipv4: Invalid header for multicast route get request");
2488	return -EINVAL;
2489	}
2490
2491	if (!netlink_strict_get_check(skb))
2492	return nlmsg_parse_deprecated(nlh, hdrlen: sizeof(*rtm), tb, RTA_MAX,
2493	policy: rtm_ipv4_policy, extack);
2494
2495	rtm = nlmsg_data(nlh);
2496	if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) ||
2497	(rtm->rtm_dst_len && rtm->rtm_dst_len != 32) ||
2498	rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol ||
2499	rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) {
2500	NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for multicast route get request");
2501	return -EINVAL;
2502	}
2503
2504	err = nlmsg_parse_deprecated_strict(nlh, hdrlen: sizeof(*rtm), tb, RTA_MAX,
2505	policy: rtm_ipv4_policy, extack);
2506	if (err)
2507	return err;
2508
2509	if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
2510	(tb[RTA_DST] && !rtm->rtm_dst_len)) {
2511	NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4");
2512	return -EINVAL;
2513	}
2514
2515	for (i = 0; i <= RTA_MAX; i++) {
2516	if (!tb[i])
2517	continue;
2518
2519	switch (i) {
2520	case RTA_SRC:
2521	case RTA_DST:
2522	case RTA_TABLE:
2523	break;
2524	default:
2525	NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in multicast route get request");
2526	return -EINVAL;
2527	}
2528	}
2529
2530	return 0;
2531	}
2532
2533	static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2534	struct netlink_ext_ack *extack)
2535	{
2536	struct net *net = sock_net(sk: in_skb->sk);
2537	struct nlattr *tb[RTA_MAX + 1];
2538	struct sk_buff *skb = NULL;
2539	struct mfc_cache *cache;
2540	struct mr_table *mrt;
2541	__be32 src, grp;
2542	u32 tableid;
2543	int err;
2544
2545	err = ipmr_rtm_valid_getroute_req(skb: in_skb, nlh, tb, extack);
2546	if (err < 0)
2547	goto errout;
2548
2549	src = tb[RTA_SRC] ? nla_get_in_addr(nla: tb[RTA_SRC]) : 0;
2550	grp = tb[RTA_DST] ? nla_get_in_addr(nla: tb[RTA_DST]) : 0;
2551	tableid = tb[RTA_TABLE] ? nla_get_u32(nla: tb[RTA_TABLE]) : 0;
2552
2553	mrt = ipmr_get_table(net, id: tableid ? tableid : RT_TABLE_DEFAULT);
2554	if (!mrt) {
2555	err = -ENOENT;
2556	goto errout_free;
2557	}
2558
2559	/* entries are added/deleted only under RTNL */
2560	rcu_read_lock();
2561	cache = ipmr_cache_find(mrt, origin: src, mcastgrp: grp);
2562	rcu_read_unlock();
2563	if (!cache) {
2564	err = -ENOENT;
2565	goto errout_free;
2566	}
2567
2568	skb = nlmsg_new(payload: mroute_msgsize(unresolved: false, maxvif: mrt->maxvif), GFP_KERNEL);
2569	if (!skb) {
2570	err = -ENOBUFS;
2571	goto errout_free;
2572	}
2573
2574	err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
2575	seq: nlh->nlmsg_seq, c: cache,
2576	RTM_NEWROUTE, flags: 0);
2577	if (err < 0)
2578	goto errout_free;
2579
2580	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2581
2582	errout:
2583	return err;
2584
2585	errout_free:
2586	kfree_skb(skb);
2587	goto errout;
2588	}
2589
2590	static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2591	{
2592	struct fib_dump_filter filter = {
2593	.rtnl_held = true,
2594	};
2595	int err;
2596
2597	if (cb->strict_check) {
2598	err = ip_valid_fib_dump_req(net: sock_net(sk: skb->sk), nlh: cb->nlh,
2599	filter: &filter, cb);
2600	if (err < 0)
2601	return err;
2602	}
2603
2604	if (filter.table_id) {
2605	struct mr_table *mrt;
2606
2607	mrt = ipmr_get_table(net: sock_net(sk: skb->sk), id: filter.table_id);
2608	if (!mrt) {
2609	if (rtnl_msg_family(nlh: cb->nlh) != RTNL_FAMILY_IPMR)
2610	return skb->len;
2611
2612	NL_SET_ERR_MSG(cb->extack, "ipv4: MR table does not exist");
2613	return -ENOENT;
2614	}
2615	err = mr_table_dump(mrt, skb, cb, fill: _ipmr_fill_mroute,
2616	lock: &mfc_unres_lock, filter: &filter);
2617	return skb->len ? : err;
2618	}
2619
2620	return mr_rtm_dumproute(skb, cb, iter: ipmr_mr_table_iter,
2621	fill: _ipmr_fill_mroute, lock: &mfc_unres_lock, filter: &filter);
2622	}
2623
2624	static const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = {
2625	[RTA_SRC] = { .type = NLA_U32 },
2626	[RTA_DST] = { .type = NLA_U32 },
2627	[RTA_IIF] = { .type = NLA_U32 },
2628	[RTA_TABLE] = { .type = NLA_U32 },
2629	[RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
2630	};
2631
2632	static bool ipmr_rtm_validate_proto(unsigned char rtm_protocol)
2633	{
2634	switch (rtm_protocol) {
2635	case RTPROT_STATIC:
2636	case RTPROT_MROUTED:
2637	return true;
2638	}
2639	return false;
2640	}
2641
2642	static int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc)
2643	{
2644	struct rtnexthop *rtnh = nla_data(nla);
2645	int remaining = nla_len(nla), vifi = 0;
2646
2647	while (rtnh_ok(rtnh, remaining)) {
2648	mfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops;
2649	if (++vifi == MAXVIFS)
2650	break;
2651	rtnh = rtnh_next(rtnh, remaining: &remaining);
2652	}
2653
2654	return remaining > 0 ? -EINVAL : vifi;
2655	}
2656
2657	/* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY */
2658	static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh,
2659	struct mfcctl *mfcc, int *mrtsock,
2660	struct mr_table **mrtret,
2661	struct netlink_ext_ack *extack)
2662	{
2663	struct net_device *dev = NULL;
2664	u32 tblid = RT_TABLE_DEFAULT;
2665	struct mr_table *mrt;
2666	struct nlattr *attr;
2667	struct rtmsg *rtm;
2668	int ret, rem;
2669
2670	ret = nlmsg_validate_deprecated(nlh, hdrlen: sizeof(*rtm), RTA_MAX,
2671	policy: rtm_ipmr_policy, extack);
2672	if (ret < 0)
2673	goto out;
2674	rtm = nlmsg_data(nlh);
2675
2676	ret = -EINVAL;
2677	if (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 ||
2678	rtm->rtm_type != RTN_MULTICAST ||
2679	rtm->rtm_scope != RT_SCOPE_UNIVERSE ||
2680	!ipmr_rtm_validate_proto(rtm_protocol: rtm->rtm_protocol))
2681	goto out;
2682
2683	memset(mfcc, 0, sizeof(*mfcc));
2684	mfcc->mfcc_parent = -1;
2685	ret = 0;
2686	nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) {
2687	switch (nla_type(nla: attr)) {
2688	case RTA_SRC:
2689	mfcc->mfcc_origin.s_addr = nla_get_be32(nla: attr);
2690	break;
2691	case RTA_DST:
2692	mfcc->mfcc_mcastgrp.s_addr = nla_get_be32(nla: attr);
2693	break;
2694	case RTA_IIF:
2695	dev = __dev_get_by_index(net, ifindex: nla_get_u32(nla: attr));
2696	if (!dev) {
2697	ret = -ENODEV;
2698	goto out;
2699	}
2700	break;
2701	case RTA_MULTIPATH:
2702	if (ipmr_nla_get_ttls(nla: attr, mfcc) < 0) {
2703	ret = -EINVAL;
2704	goto out;
2705	}
2706	break;
2707	case RTA_PREFSRC:
2708	ret = 1;
2709	break;
2710	case RTA_TABLE:
2711	tblid = nla_get_u32(nla: attr);
2712	break;
2713	}
2714	}
2715	mrt = ipmr_get_table(net, id: tblid);
2716	if (!mrt) {
2717	ret = -ENOENT;
2718	goto out;
2719	}
2720	*mrtret = mrt;
2721	*mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0;
2722	if (dev)
2723	mfcc->mfcc_parent = ipmr_find_vif(mrt, dev);
2724
2725	out:
2726	return ret;
2727	}
2728
2729	/* takes care of both newroute and delroute */
2730	static int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh,
2731	struct netlink_ext_ack *extack)
2732	{
2733	struct net *net = sock_net(sk: skb->sk);
2734	int ret, mrtsock, parent;
2735	struct mr_table *tbl;
2736	struct mfcctl mfcc;
2737
2738	mrtsock = 0;
2739	tbl = NULL;
2740	ret = rtm_to_ipmr_mfcc(net, nlh, mfcc: &mfcc, mrtsock: &mrtsock, mrtret: &tbl, extack);
2741	if (ret < 0)
2742	return ret;
2743
2744	parent = ret ? mfcc.mfcc_parent : -1;
2745	if (nlh->nlmsg_type == RTM_NEWROUTE)
2746	return ipmr_mfc_add(net, mrt: tbl, mfc: &mfcc, mrtsock, parent);
2747	else
2748	return ipmr_mfc_delete(mrt: tbl, mfc: &mfcc, parent);
2749	}
2750
2751	static bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb)
2752	{
2753	u32 queue_len = atomic_read(v: &mrt->cache_resolve_queue_len);
2754
2755	if (nla_put_u32(skb, attrtype: IPMRA_TABLE_ID, value: mrt->id) ||
2756	nla_put_u32(skb, attrtype: IPMRA_TABLE_CACHE_RES_QUEUE_LEN, value: queue_len) ||
2757	nla_put_s32(skb, attrtype: IPMRA_TABLE_MROUTE_REG_VIF_NUM,
2758	value: mrt->mroute_reg_vif_num) ||
2759	nla_put_u8(skb, attrtype: IPMRA_TABLE_MROUTE_DO_ASSERT,
2760	value: mrt->mroute_do_assert) ||
2761	nla_put_u8(skb, attrtype: IPMRA_TABLE_MROUTE_DO_PIM, value: mrt->mroute_do_pim) ||
2762	nla_put_u8(skb, attrtype: IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE,
2763	value: mrt->mroute_do_wrvifwhole))
2764	return false;
2765
2766	return true;
2767	}
2768
2769	static bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb)
2770	{
2771	struct net_device *vif_dev;
2772	struct nlattr *vif_nest;
2773	struct vif_device *vif;
2774
2775	vif = &mrt->vif_table[vifid];
2776	vif_dev = rtnl_dereference(vif->dev);
2777	/* if the VIF doesn't exist just continue */
2778	if (!vif_dev)
2779	return true;
2780
2781	vif_nest = nla_nest_start_noflag(skb, attrtype: IPMRA_VIF);
2782	if (!vif_nest)
2783	return false;
2784
2785	if (nla_put_u32(skb, attrtype: IPMRA_VIFA_IFINDEX, value: vif_dev->ifindex) ||
2786	nla_put_u32(skb, attrtype: IPMRA_VIFA_VIF_ID, value: vifid) ||
2787	nla_put_u16(skb, attrtype: IPMRA_VIFA_FLAGS, value: vif->flags) ||
2788	nla_put_u64_64bit(skb, attrtype: IPMRA_VIFA_BYTES_IN, value: vif->bytes_in,
2789	padattr: IPMRA_VIFA_PAD) ||
2790	nla_put_u64_64bit(skb, attrtype: IPMRA_VIFA_BYTES_OUT, value: vif->bytes_out,
2791	padattr: IPMRA_VIFA_PAD) ||
2792	nla_put_u64_64bit(skb, attrtype: IPMRA_VIFA_PACKETS_IN, value: vif->pkt_in,
2793	padattr: IPMRA_VIFA_PAD) ||
2794	nla_put_u64_64bit(skb, attrtype: IPMRA_VIFA_PACKETS_OUT, value: vif->pkt_out,
2795	padattr: IPMRA_VIFA_PAD) ||
2796	nla_put_be32(skb, attrtype: IPMRA_VIFA_LOCAL_ADDR, value: vif->local) ||
2797	nla_put_be32(skb, attrtype: IPMRA_VIFA_REMOTE_ADDR, value: vif->remote)) {
2798	nla_nest_cancel(skb, start: vif_nest);
2799	return false;
2800	}
2801	nla_nest_end(skb, start: vif_nest);
2802
2803	return true;
2804	}
2805
2806	static int ipmr_valid_dumplink(const struct nlmsghdr *nlh,
2807	struct netlink_ext_ack *extack)
2808	{
2809	struct ifinfomsg *ifm;
2810
2811	if (nlh->nlmsg_len < nlmsg_msg_size(payload: sizeof(*ifm))) {
2812	NL_SET_ERR_MSG(extack, "ipv4: Invalid header for ipmr link dump");
2813	return -EINVAL;
2814	}
2815
2816	if (nlmsg_attrlen(nlh, hdrlen: sizeof(*ifm))) {
2817	NL_SET_ERR_MSG(extack, "Invalid data after header in ipmr link dump");
2818	return -EINVAL;
2819	}
2820
2821	ifm = nlmsg_data(nlh);
2822	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
2823	ifm->ifi_change || ifm->ifi_index) {
2824	NL_SET_ERR_MSG(extack, "Invalid values in header for ipmr link dump request");
2825	return -EINVAL;
2826	}
2827
2828	return 0;
2829	}
2830
2831	static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb)
2832	{
2833	struct net *net = sock_net(sk: skb->sk);
2834	struct nlmsghdr *nlh = NULL;
2835	unsigned int t = 0, s_t;
2836	unsigned int e = 0, s_e;
2837	struct mr_table *mrt;
2838
2839	if (cb->strict_check) {
2840	int err = ipmr_valid_dumplink(nlh: cb->nlh, extack: cb->extack);
2841
2842	if (err < 0)
2843	return err;
2844	}
2845
2846	s_t = cb->args[0];
2847	s_e = cb->args[1];
2848
2849	ipmr_for_each_table(mrt, net) {
2850	struct nlattr *vifs, *af;
2851	struct ifinfomsg *hdr;
2852	u32 i;
2853
2854	if (t < s_t)
2855	goto skip_table;
2856	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
2857	seq: cb->nlh->nlmsg_seq, RTM_NEWLINK,
2858	payload: sizeof(*hdr), NLM_F_MULTI);
2859	if (!nlh)
2860	break;
2861
2862	hdr = nlmsg_data(nlh);
2863	memset(hdr, 0, sizeof(*hdr));
2864	hdr->ifi_family = RTNL_FAMILY_IPMR;
2865
2866	af = nla_nest_start_noflag(skb, attrtype: IFLA_AF_SPEC);
2867	if (!af) {
2868	nlmsg_cancel(skb, nlh);
2869	goto out;
2870	}
2871
2872	if (!ipmr_fill_table(mrt, skb)) {
2873	nlmsg_cancel(skb, nlh);
2874	goto out;
2875	}
2876
2877	vifs = nla_nest_start_noflag(skb, attrtype: IPMRA_TABLE_VIFS);
2878	if (!vifs) {
2879	nla_nest_end(skb, start: af);
2880	nlmsg_end(skb, nlh);
2881	goto out;
2882	}
2883	for (i = 0; i < mrt->maxvif; i++) {
2884	if (e < s_e)
2885	goto skip_entry;
2886	if (!ipmr_fill_vif(mrt, vifid: i, skb)) {
2887	nla_nest_end(skb, start: vifs);
2888	nla_nest_end(skb, start: af);
2889	nlmsg_end(skb, nlh);
2890	goto out;
2891	}
2892	skip_entry:
2893	e++;
2894	}
2895	s_e = 0;
2896	e = 0;
2897	nla_nest_end(skb, start: vifs);
2898	nla_nest_end(skb, start: af);
2899	nlmsg_end(skb, nlh);
2900	skip_table:
2901	t++;
2902	}
2903
2904	out:
2905	cb->args[1] = e;
2906	cb->args[0] = t;
2907
2908	return skb->len;
2909	}
2910
2911	#ifdef CONFIG_PROC_FS
2912	/* The /proc interfaces to multicast routing :
2913	* /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2914	*/
2915
2916	static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2917	__acquires(RCU)
2918	{
2919	struct mr_vif_iter *iter = seq->private;
2920	struct net *net = seq_file_net(seq);
2921	struct mr_table *mrt;
2922
2923	mrt = ipmr_get_table(net, id: RT_TABLE_DEFAULT);
2924	if (!mrt)
2925	return ERR_PTR(error: -ENOENT);
2926
2927	iter->mrt = mrt;
2928
2929	rcu_read_lock();
2930	return mr_vif_seq_start(seq, pos);
2931	}
2932
2933	static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2934	__releases(RCU)
2935	{
2936	rcu_read_unlock();
2937	}
2938
2939	static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2940	{
2941	struct mr_vif_iter *iter = seq->private;
2942	struct mr_table *mrt = iter->mrt;
2943
2944	if (v == SEQ_START_TOKEN) {
2945	seq_puts(m: seq,
2946	s: "Interface BytesIn PktsIn BytesOut PktsOut Flags Local Remote\n");
2947	} else {
2948	const struct vif_device *vif = v;
2949	const struct net_device *vif_dev;
2950	const char *name;
2951
2952	vif_dev = vif_dev_read(vif);
2953	name = vif_dev ? vif_dev->name : "none";
2954	seq_printf(m: seq,
2955	fmt: "%2td %-10s %8ld %7ld %8ld %7ld %05X %08X %08X\n",
2956	vif - mrt->vif_table,
2957	name, vif->bytes_in, vif->pkt_in,
2958	vif->bytes_out, vif->pkt_out,
2959	vif->flags, vif->local, vif->remote);
2960	}
2961	return 0;
2962	}
2963
2964	static const struct seq_operations ipmr_vif_seq_ops = {
2965	.start = ipmr_vif_seq_start,
2966	.next = mr_vif_seq_next,
2967	.stop = ipmr_vif_seq_stop,
2968	.show = ipmr_vif_seq_show,
2969	};
2970
2971	static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2972	{
2973	struct net *net = seq_file_net(seq);
2974	struct mr_table *mrt;
2975
2976	mrt = ipmr_get_table(net, id: RT_TABLE_DEFAULT);
2977	if (!mrt)
2978	return ERR_PTR(error: -ENOENT);
2979
2980	return mr_mfc_seq_start(seq, pos, mrt, lock: &mfc_unres_lock);
2981	}
2982
2983	static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2984	{
2985	int n;
2986
2987	if (v == SEQ_START_TOKEN) {
2988	seq_puts(m: seq,
2989	s: "Group Origin Iif Pkts Bytes Wrong Oifs\n");
2990	} else {
2991	const struct mfc_cache *mfc = v;
2992	const struct mr_mfc_iter *it = seq->private;
2993	const struct mr_table *mrt = it->mrt;
2994
2995	seq_printf(m: seq, fmt: "%08X %08X %-3hd",
2996	(__force u32) mfc->mfc_mcastgrp,
2997	(__force u32) mfc->mfc_origin,
2998	mfc->_c.mfc_parent);
2999
3000	if (it->cache != &mrt->mfc_unres_queue) {
3001	seq_printf(m: seq, fmt: " %8lu %8lu %8lu",
3002	mfc->_c.mfc_un.res.pkt,
3003	mfc->_c.mfc_un.res.bytes,
3004	mfc->_c.mfc_un.res.wrong_if);
3005	for (n = mfc->_c.mfc_un.res.minvif;
3006	n < mfc->_c.mfc_un.res.maxvif; n++) {
3007	if (VIF_EXISTS(mrt, n) &&
3008	mfc->_c.mfc_un.res.ttls[n] < 255)
3009	seq_printf(m: seq,
3010	fmt: " %2d:%-3d",
3011	n, mfc->_c.mfc_un.res.ttls[n]);
3012	}
3013	} else {
3014	/* unresolved mfc_caches don't contain
3015	* pkt, bytes and wrong_if values
3016	*/
3017	seq_printf(m: seq, fmt: " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
3018	}
3019	seq_putc(m: seq, c: '\n');
3020	}
3021	return 0;
3022	}
3023
3024	static const struct seq_operations ipmr_mfc_seq_ops = {
3025	.start = ipmr_mfc_seq_start,
3026	.next = mr_mfc_seq_next,
3027	.stop = mr_mfc_seq_stop,
3028	.show = ipmr_mfc_seq_show,
3029	};
3030	#endif
3031
3032	#ifdef CONFIG_IP_PIMSM_V2
3033	static const struct net_protocol pim_protocol = {
3034	.handler = pim_rcv,
3035	};
3036	#endif
3037
3038	static unsigned int ipmr_seq_read(struct net *net)
3039	{
3040	ASSERT_RTNL();
3041
3042	return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
3043	}
3044
3045	static int ipmr_dump(struct net *net, struct notifier_block *nb,
3046	struct netlink_ext_ack *extack)
3047	{
3048	return mr_dump(net, nb, RTNL_FAMILY_IPMR, rules_dump: ipmr_rules_dump,
3049	mr_iter: ipmr_mr_table_iter, extack);
3050	}
3051
3052	static const struct fib_notifier_ops ipmr_notifier_ops_template = {
3053	.family = RTNL_FAMILY_IPMR,
3054	.fib_seq_read = ipmr_seq_read,
3055	.fib_dump = ipmr_dump,
3056	.owner = THIS_MODULE,
3057	};
3058
3059	static int __net_init ipmr_notifier_init(struct net *net)
3060	{
3061	struct fib_notifier_ops *ops;
3062
3063	net->ipv4.ipmr_seq = 0;
3064
3065	ops = fib_notifier_ops_register(tmpl: &ipmr_notifier_ops_template, net);
3066	if (IS_ERR(ptr: ops))
3067	return PTR_ERR(ptr: ops);
3068	net->ipv4.ipmr_notifier_ops = ops;
3069
3070	return 0;
3071	}
3072
3073	static void __net_exit ipmr_notifier_exit(struct net *net)
3074	{
3075	fib_notifier_ops_unregister(ops: net->ipv4.ipmr_notifier_ops);
3076	net->ipv4.ipmr_notifier_ops = NULL;
3077	}
3078
3079	/* Setup for IP multicast routing */
3080	static int __net_init ipmr_net_init(struct net *net)
3081	{
3082	int err;
3083
3084	err = ipmr_notifier_init(net);
3085	if (err)
3086	goto ipmr_notifier_fail;
3087
3088	err = ipmr_rules_init(net);
3089	if (err < 0)
3090	goto ipmr_rules_fail;
3091
3092	#ifdef CONFIG_PROC_FS
3093	err = -ENOMEM;
3094	if (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops,
3095	sizeof(struct mr_vif_iter)))
3096	goto proc_vif_fail;
3097	if (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
3098	sizeof(struct mr_mfc_iter)))
3099	goto proc_cache_fail;
3100	#endif
3101	return 0;
3102
3103	#ifdef CONFIG_PROC_FS
3104	proc_cache_fail:
3105	remove_proc_entry("ip_mr_vif", net->proc_net);
3106	proc_vif_fail:
3107	rtnl_lock();
3108	ipmr_rules_exit(net);
3109	rtnl_unlock();
3110	#endif
3111	ipmr_rules_fail:
3112	ipmr_notifier_exit(net);
3113	ipmr_notifier_fail:
3114	return err;
3115	}
3116
3117	static void __net_exit ipmr_net_exit(struct net *net)
3118	{
3119	#ifdef CONFIG_PROC_FS
3120	remove_proc_entry("ip_mr_cache", net->proc_net);
3121	remove_proc_entry("ip_mr_vif", net->proc_net);
3122	#endif
3123	ipmr_notifier_exit(net);
3124	}
3125
3126	static void __net_exit ipmr_net_exit_batch(struct list_head *net_list)
3127	{
3128	struct net *net;
3129
3130	rtnl_lock();
3131	list_for_each_entry(net, net_list, exit_list)
3132	ipmr_rules_exit(net);
3133	rtnl_unlock();
3134	}
3135
3136	static struct pernet_operations ipmr_net_ops = {
3137	.init = ipmr_net_init,
3138	.exit = ipmr_net_exit,
3139	.exit_batch = ipmr_net_exit_batch,
3140	};
3141
3142	int __init ip_mr_init(void)
3143	{
3144	int err;
3145
3146	mrt_cachep = KMEM_CACHE(mfc_cache, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
3147
3148	err = register_pernet_subsys(&ipmr_net_ops);
3149	if (err)
3150	goto reg_pernet_fail;
3151
3152	err = register_netdevice_notifier(nb: &ip_mr_notifier);
3153	if (err)
3154	goto reg_notif_fail;
3155	#ifdef CONFIG_IP_PIMSM_V2
3156	if (inet_add_protocol(prot: &pim_protocol, IPPROTO_PIM) < 0) {
3157	pr_err("%s: can't add PIM protocol\n", __func__);
3158	err = -EAGAIN;
3159	goto add_proto_fail;
3160	}
3161	#endif
3162	rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
3163	ipmr_rtm_getroute, ipmr_rtm_dumproute, flags: 0);
3164	rtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE,
3165	ipmr_rtm_route, NULL, flags: 0);
3166	rtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE,
3167	ipmr_rtm_route, NULL, flags: 0);
3168
3169	rtnl_register(RTNL_FAMILY_IPMR, RTM_GETLINK,
3170	NULL, ipmr_rtm_dumplink, flags: 0);
3171	return 0;
3172
3173	#ifdef CONFIG_IP_PIMSM_V2
3174	add_proto_fail:
3175	unregister_netdevice_notifier(nb: &ip_mr_notifier);
3176	#endif
3177	reg_notif_fail:
3178	unregister_pernet_subsys(&ipmr_net_ops);
3179	reg_pernet_fail:
3180	kmem_cache_destroy(s: mrt_cachep);
3181	return err;
3182	}
3183