1/*
2 *	IP multicast routing support for mrouted 3.6/3.8
3 *
4 *		(c) 1995 Alan Cox, <alan@lxorguk.ukuu.org.uk>
5 *	  Linux Consultancy and Custom Driver Development
6 *
7 *	This program is free software; you can redistribute it and/or
8 *	modify it under the terms of the GNU General Public License
9 *	as published by the Free Software Foundation; either version
10 *	2 of the License, or (at your option) any later version.
11 *
12 *	Fixes:
13 *	Michael Chastain	:	Incorrect size of copying.
14 *	Alan Cox		:	Added the cache manager code
15 *	Alan Cox		:	Fixed the clone/copy bug and device race.
16 *	Mike McLagan		:	Routing by source
17 *	Malcolm Beattie		:	Buffer handling fixes.
18 *	Alexey Kuznetsov	:	Double buffer free and other fixes.
19 *	SVR Anand		:	Fixed several multicast bugs and problems.
20 *	Alexey Kuznetsov	:	Status, optimisations and more.
21 *	Brad Parker		:	Better behaviour on mrouted upcall
22 *					overflow.
23 *      Carlos Picoto           :       PIMv1 Support
24 *	Pavlin Ivanov Radoslavov:	PIMv2 Registers must checksum only PIM header
25 *					Relax this requirement to work with older peers.
26 *
27 */
28
29#include <asm/uaccess.h>
30#include <linux/types.h>
31#include <linux/capability.h>
32#include <linux/errno.h>
33#include <linux/timer.h>
34#include <linux/mm.h>
35#include <linux/kernel.h>
36#include <linux/fcntl.h>
37#include <linux/stat.h>
38#include <linux/socket.h>
39#include <linux/in.h>
40#include <linux/inet.h>
41#include <linux/netdevice.h>
42#include <linux/inetdevice.h>
43#include <linux/igmp.h>
44#include <linux/proc_fs.h>
45#include <linux/seq_file.h>
46#include <linux/mroute.h>
47#include <linux/init.h>
48#include <linux/if_ether.h>
49#include <linux/slab.h>
50#include <net/net_namespace.h>
51#include <net/ip.h>
52#include <net/protocol.h>
53#include <linux/skbuff.h>
54#include <net/route.h>
55#include <net/sock.h>
56#include <net/icmp.h>
57#include <net/udp.h>
58#include <net/raw.h>
59#include <linux/notifier.h>
60#include <linux/if_arp.h>
61#include <linux/netfilter_ipv4.h>
62#include <linux/compat.h>
63#include <linux/export.h>
64#include <net/ip_tunnels.h>
65#include <net/checksum.h>
66#include <net/netlink.h>
67#include <net/fib_rules.h>
68#include <linux/netconf.h>
69
70#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
71#define CONFIG_IP_PIMSM	1
72#endif
73
74struct mr_table {
75	struct list_head	list;
76#ifdef CONFIG_NET_NS
77	struct net		*net;
78#endif
79	u32			id;
80	struct sock __rcu	*mroute_sk;
81	struct timer_list	ipmr_expire_timer;
82	struct list_head	mfc_unres_queue;
83	struct list_head	mfc_cache_array[MFC_LINES];
84	struct vif_device	vif_table[MAXVIFS];
85	int			maxvif;
86	atomic_t		cache_resolve_queue_len;
87	bool			mroute_do_assert;
88	bool			mroute_do_pim;
89#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
90	int			mroute_reg_vif_num;
91#endif
92};
93
94struct ipmr_rule {
95	struct fib_rule		common;
96};
97
98struct ipmr_result {
99	struct mr_table		*mrt;
100};
101
102/* Big lock, protecting vif table, mrt cache and mroute socket state.
103 * Note that the changes are semaphored via rtnl_lock.
104 */
105
106static DEFINE_RWLOCK(mrt_lock);
107
108/*
109 *	Multicast router control variables
110 */
111
112#define VIF_EXISTS(_mrt, _idx) ((_mrt)->vif_table[_idx].dev != NULL)
113
114/* Special spinlock for queue of unresolved entries */
115static DEFINE_SPINLOCK(mfc_unres_lock);
116
117/* We return to original Alan's scheme. Hash table of resolved
118 * entries is changed only in process context and protected
119 * with weak lock mrt_lock. Queue of unresolved entries is protected
120 * with strong spinlock mfc_unres_lock.
121 *
122 * In this case data path is free of exclusive locks at all.
123 */
124
125static struct kmem_cache *mrt_cachep __read_mostly;
126
127static struct mr_table *ipmr_new_table(struct net *net, u32 id);
128static void ipmr_free_table(struct mr_table *mrt);
129
130static void ip_mr_forward(struct net *net, struct mr_table *mrt,
131			  struct sk_buff *skb, struct mfc_cache *cache,
132			  int local);
133static int ipmr_cache_report(struct mr_table *mrt,
134			     struct sk_buff *pkt, vifi_t vifi, int assert);
135static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
136			      struct mfc_cache *c, struct rtmsg *rtm);
137static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
138				 int cmd);
139static void mroute_clean_tables(struct mr_table *mrt);
140static void ipmr_expire_process(unsigned long arg);
141
142#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
143#define ipmr_for_each_table(mrt, net) \
144	list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list)
145
146static struct mr_table *ipmr_get_table(struct net *net, u32 id)
147{
148	struct mr_table *mrt;
149
150	ipmr_for_each_table(mrt, net) {
151		if (mrt->id == id)
152			return mrt;
153	}
154	return NULL;
155}
156
157static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
158			   struct mr_table **mrt)
159{
160	int err;
161	struct ipmr_result res;
162	struct fib_lookup_arg arg = {
163		.result = &res,
164		.flags = FIB_LOOKUP_NOREF,
165	};
166
167	err = fib_rules_lookup(net->ipv4.mr_rules_ops,
168			       flowi4_to_flowi(flp4), 0, &arg);
169	if (err < 0)
170		return err;
171	*mrt = res.mrt;
172	return 0;
173}
174
175static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
176			    int flags, struct fib_lookup_arg *arg)
177{
178	struct ipmr_result *res = arg->result;
179	struct mr_table *mrt;
180
181	switch (rule->action) {
182	case FR_ACT_TO_TBL:
183		break;
184	case FR_ACT_UNREACHABLE:
185		return -ENETUNREACH;
186	case FR_ACT_PROHIBIT:
187		return -EACCES;
188	case FR_ACT_BLACKHOLE:
189	default:
190		return -EINVAL;
191	}
192
193	mrt = ipmr_get_table(rule->fr_net, rule->table);
194	if (mrt == NULL)
195		return -EAGAIN;
196	res->mrt = mrt;
197	return 0;
198}
199
200static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
201{
202	return 1;
203}
204
205static const struct nla_policy ipmr_rule_policy[FRA_MAX + 1] = {
206	FRA_GENERIC_POLICY,
207};
208
209static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
210			       struct fib_rule_hdr *frh, struct nlattr **tb)
211{
212	return 0;
213}
214
215static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
216			     struct nlattr **tb)
217{
218	return 1;
219}
220
221static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
222			  struct fib_rule_hdr *frh)
223{
224	frh->dst_len = 0;
225	frh->src_len = 0;
226	frh->tos     = 0;
227	return 0;
228}
229
230static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
231	.family		= RTNL_FAMILY_IPMR,
232	.rule_size	= sizeof(struct ipmr_rule),
233	.addr_size	= sizeof(u32),
234	.action		= ipmr_rule_action,
235	.match		= ipmr_rule_match,
236	.configure	= ipmr_rule_configure,
237	.compare	= ipmr_rule_compare,
238	.default_pref	= fib_default_rule_pref,
239	.fill		= ipmr_rule_fill,
240	.nlgroup	= RTNLGRP_IPV4_RULE,
241	.policy		= ipmr_rule_policy,
242	.owner		= THIS_MODULE,
243};
244
245static int __net_init ipmr_rules_init(struct net *net)
246{
247	struct fib_rules_ops *ops;
248	struct mr_table *mrt;
249	int err;
250
251	ops = fib_rules_register(&ipmr_rules_ops_template, net);
252	if (IS_ERR(ops))
253		return PTR_ERR(ops);
254
255	INIT_LIST_HEAD(&net->ipv4.mr_tables);
256
257	mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
258	if (mrt == NULL) {
259		err = -ENOMEM;
260		goto err1;
261	}
262
263	err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
264	if (err < 0)
265		goto err2;
266
267	net->ipv4.mr_rules_ops = ops;
268	return 0;
269
270err2:
271	kfree(mrt);
272err1:
273	fib_rules_unregister(ops);
274	return err;
275}
276
277static void __net_exit ipmr_rules_exit(struct net *net)
278{
279	struct mr_table *mrt, *next;
280
281	list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
282		list_del(&mrt->list);
283		ipmr_free_table(mrt);
284	}
285	fib_rules_unregister(net->ipv4.mr_rules_ops);
286}
287#else
288#define ipmr_for_each_table(mrt, net) \
289	for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
290
291static struct mr_table *ipmr_get_table(struct net *net, u32 id)
292{
293	return net->ipv4.mrt;
294}
295
296static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
297			   struct mr_table **mrt)
298{
299	*mrt = net->ipv4.mrt;
300	return 0;
301}
302
303static int __net_init ipmr_rules_init(struct net *net)
304{
305	net->ipv4.mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
306	return net->ipv4.mrt ? 0 : -ENOMEM;
307}
308
309static void __net_exit ipmr_rules_exit(struct net *net)
310{
311	ipmr_free_table(net->ipv4.mrt);
312}
313#endif
314
315static struct mr_table *ipmr_new_table(struct net *net, u32 id)
316{
317	struct mr_table *mrt;
318	unsigned int i;
319
320	mrt = ipmr_get_table(net, id);
321	if (mrt != NULL)
322		return mrt;
323
324	mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
325	if (mrt == NULL)
326		return NULL;
327	write_pnet(&mrt->net, net);
328	mrt->id = id;
329
330	/* Forwarding cache */
331	for (i = 0; i < MFC_LINES; i++)
332		INIT_LIST_HEAD(&mrt->mfc_cache_array[i]);
333
334	INIT_LIST_HEAD(&mrt->mfc_unres_queue);
335
336	setup_timer(&mrt->ipmr_expire_timer, ipmr_expire_process,
337		    (unsigned long)mrt);
338
339#ifdef CONFIG_IP_PIMSM
340	mrt->mroute_reg_vif_num = -1;
341#endif
342#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
343	list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
344#endif
345	return mrt;
346}
347
348static void ipmr_free_table(struct mr_table *mrt)
349{
350	del_timer_sync(&mrt->ipmr_expire_timer);
351	mroute_clean_tables(mrt);
352	kfree(mrt);
353}
354
355/* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
356
357static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
358{
359	struct net *net = dev_net(dev);
360
361	dev_close(dev);
362
363	dev = __dev_get_by_name(net, "tunl0");
364	if (dev) {
365		const struct net_device_ops *ops = dev->netdev_ops;
366		struct ifreq ifr;
367		struct ip_tunnel_parm p;
368
369		memset(&p, 0, sizeof(p));
370		p.iph.daddr = v->vifc_rmt_addr.s_addr;
371		p.iph.saddr = v->vifc_lcl_addr.s_addr;
372		p.iph.version = 4;
373		p.iph.ihl = 5;
374		p.iph.protocol = IPPROTO_IPIP;
375		sprintf(p.name, "dvmrp%d", v->vifc_vifi);
376		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
377
378		if (ops->ndo_do_ioctl) {
379			mm_segment_t oldfs = get_fs();
380
381			set_fs(KERNEL_DS);
382			ops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
383			set_fs(oldfs);
384		}
385	}
386}
387
388static
389struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
390{
391	struct net_device  *dev;
392
393	dev = __dev_get_by_name(net, "tunl0");
394
395	if (dev) {
396		const struct net_device_ops *ops = dev->netdev_ops;
397		int err;
398		struct ifreq ifr;
399		struct ip_tunnel_parm p;
400		struct in_device  *in_dev;
401
402		memset(&p, 0, sizeof(p));
403		p.iph.daddr = v->vifc_rmt_addr.s_addr;
404		p.iph.saddr = v->vifc_lcl_addr.s_addr;
405		p.iph.version = 4;
406		p.iph.ihl = 5;
407		p.iph.protocol = IPPROTO_IPIP;
408		sprintf(p.name, "dvmrp%d", v->vifc_vifi);
409		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
410
411		if (ops->ndo_do_ioctl) {
412			mm_segment_t oldfs = get_fs();
413
414			set_fs(KERNEL_DS);
415			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
416			set_fs(oldfs);
417		} else {
418			err = -EOPNOTSUPP;
419		}
420		dev = NULL;
421
422		if (err == 0 &&
423		    (dev = __dev_get_by_name(net, p.name)) != NULL) {
424			dev->flags |= IFF_MULTICAST;
425
426			in_dev = __in_dev_get_rtnl(dev);
427			if (in_dev == NULL)
428				goto failure;
429
430			ipv4_devconf_setall(in_dev);
431			neigh_parms_data_state_setall(in_dev->arp_parms);
432			IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
433
434			if (dev_open(dev))
435				goto failure;
436			dev_hold(dev);
437		}
438	}
439	return dev;
440
441failure:
442	/* allow the register to be completed before unregistering. */
443	rtnl_unlock();
444	rtnl_lock();
445
446	unregister_netdevice(dev);
447	return NULL;
448}
449
450#ifdef CONFIG_IP_PIMSM
451
452static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
453{
454	struct net *net = dev_net(dev);
455	struct mr_table *mrt;
456	struct flowi4 fl4 = {
457		.flowi4_oif	= dev->ifindex,
458		.flowi4_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
459		.flowi4_mark	= skb->mark,
460	};
461	int err;
462
463	err = ipmr_fib_lookup(net, &fl4, &mrt);
464	if (err < 0) {
465		kfree_skb(skb);
466		return err;
467	}
468
469	read_lock(&mrt_lock);
470	dev->stats.tx_bytes += skb->len;
471	dev->stats.tx_packets++;
472	ipmr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, IGMPMSG_WHOLEPKT);
473	read_unlock(&mrt_lock);
474	kfree_skb(skb);
475	return NETDEV_TX_OK;
476}
477
478static const struct net_device_ops reg_vif_netdev_ops = {
479	.ndo_start_xmit	= reg_vif_xmit,
480};
481
482static void reg_vif_setup(struct net_device *dev)
483{
484	dev->type		= ARPHRD_PIMREG;
485	dev->mtu		= ETH_DATA_LEN - sizeof(struct iphdr) - 8;
486	dev->flags		= IFF_NOARP;
487	dev->netdev_ops		= &reg_vif_netdev_ops;
488	dev->destructor		= free_netdev;
489	dev->features		|= NETIF_F_NETNS_LOCAL;
490}
491
492static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
493{
494	struct net_device *dev;
495	struct in_device *in_dev;
496	char name[IFNAMSIZ];
497
498	if (mrt->id == RT_TABLE_DEFAULT)
499		sprintf(name, "pimreg");
500	else
501		sprintf(name, "pimreg%u", mrt->id);
502
503	dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
504
505	if (dev == NULL)
506		return NULL;
507
508	dev_net_set(dev, net);
509
510	if (register_netdevice(dev)) {
511		free_netdev(dev);
512		return NULL;
513	}
514	dev->iflink = 0;
515
516	rcu_read_lock();
517	in_dev = __in_dev_get_rcu(dev);
518	if (!in_dev) {
519		rcu_read_unlock();
520		goto failure;
521	}
522
523	ipv4_devconf_setall(in_dev);
524	neigh_parms_data_state_setall(in_dev->arp_parms);
525	IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
526	rcu_read_unlock();
527
528	if (dev_open(dev))
529		goto failure;
530
531	dev_hold(dev);
532
533	return dev;
534
535failure:
536	/* allow the register to be completed before unregistering. */
537	rtnl_unlock();
538	rtnl_lock();
539
540	unregister_netdevice(dev);
541	return NULL;
542}
543#endif
544
545/**
546 *	vif_delete - Delete a VIF entry
547 *	@notify: Set to 1, if the caller is a notifier_call
548 */
549
550static int vif_delete(struct mr_table *mrt, int vifi, int notify,
551		      struct list_head *head)
552{
553	struct vif_device *v;
554	struct net_device *dev;
555	struct in_device *in_dev;
556
557	if (vifi < 0 || vifi >= mrt->maxvif)
558		return -EADDRNOTAVAIL;
559
560	v = &mrt->vif_table[vifi];
561
562	write_lock_bh(&mrt_lock);
563	dev = v->dev;
564	v->dev = NULL;
565
566	if (!dev) {
567		write_unlock_bh(&mrt_lock);
568		return -EADDRNOTAVAIL;
569	}
570
571#ifdef CONFIG_IP_PIMSM
572	if (vifi == mrt->mroute_reg_vif_num)
573		mrt->mroute_reg_vif_num = -1;
574#endif
575
576	if (vifi + 1 == mrt->maxvif) {
577		int tmp;
578
579		for (tmp = vifi - 1; tmp >= 0; tmp--) {
580			if (VIF_EXISTS(mrt, tmp))
581				break;
582		}
583		mrt->maxvif = tmp+1;
584	}
585
586	write_unlock_bh(&mrt_lock);
587
588	dev_set_allmulti(dev, -1);
589
590	in_dev = __in_dev_get_rtnl(dev);
591	if (in_dev) {
592		IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
593		inet_netconf_notify_devconf(dev_net(dev),
594					    NETCONFA_MC_FORWARDING,
595					    dev->ifindex, &in_dev->cnf);
596		ip_rt_multicast_event(in_dev);
597	}
598
599	if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
600		unregister_netdevice_queue(dev, head);
601
602	dev_put(dev);
603	return 0;
604}
605
606static void ipmr_cache_free_rcu(struct rcu_head *head)
607{
608	struct mfc_cache *c = container_of(head, struct mfc_cache, rcu);
609
610	kmem_cache_free(mrt_cachep, c);
611}
612
613static inline void ipmr_cache_free(struct mfc_cache *c)
614{
615	call_rcu(&c->rcu, ipmr_cache_free_rcu);
616}
617
618/* Destroy an unresolved cache entry, killing queued skbs
619 * and reporting error to netlink readers.
620 */
621
622static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
623{
624	struct net *net = read_pnet(&mrt->net);
625	struct sk_buff *skb;
626	struct nlmsgerr *e;
627
628	atomic_dec(&mrt->cache_resolve_queue_len);
629
630	while ((skb = skb_dequeue(&c->mfc_un.unres.unresolved))) {
631		if (ip_hdr(skb)->version == 0) {
632			struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
633			nlh->nlmsg_type = NLMSG_ERROR;
634			nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
635			skb_trim(skb, nlh->nlmsg_len);
636			e = nlmsg_data(nlh);
637			e->error = -ETIMEDOUT;
638			memset(&e->msg, 0, sizeof(e->msg));
639
640			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
641		} else {
642			kfree_skb(skb);
643		}
644	}
645
646	ipmr_cache_free(c);
647}
648
649
650/* Timer process for the unresolved queue. */
651
652static void ipmr_expire_process(unsigned long arg)
653{
654	struct mr_table *mrt = (struct mr_table *)arg;
655	unsigned long now;
656	unsigned long expires;
657	struct mfc_cache *c, *next;
658
659	if (!spin_trylock(&mfc_unres_lock)) {
660		mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10);
661		return;
662	}
663
664	if (list_empty(&mrt->mfc_unres_queue))
665		goto out;
666
667	now = jiffies;
668	expires = 10*HZ;
669
670	list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
671		if (time_after(c->mfc_un.unres.expires, now)) {
672			unsigned long interval = c->mfc_un.unres.expires - now;
673			if (interval < expires)
674				expires = interval;
675			continue;
676		}
677
678		list_del(&c->list);
679		mroute_netlink_event(mrt, c, RTM_DELROUTE);
680		ipmr_destroy_unres(mrt, c);
681	}
682
683	if (!list_empty(&mrt->mfc_unres_queue))
684		mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
685
686out:
687	spin_unlock(&mfc_unres_lock);
688}
689
690/* Fill oifs list. It is called under write locked mrt_lock. */
691
692static void ipmr_update_thresholds(struct mr_table *mrt, struct mfc_cache *cache,
693				   unsigned char *ttls)
694{
695	int vifi;
696
697	cache->mfc_un.res.minvif = MAXVIFS;
698	cache->mfc_un.res.maxvif = 0;
699	memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
700
701	for (vifi = 0; vifi < mrt->maxvif; vifi++) {
702		if (VIF_EXISTS(mrt, vifi) &&
703		    ttls[vifi] && ttls[vifi] < 255) {
704			cache->mfc_un.res.ttls[vifi] = ttls[vifi];
705			if (cache->mfc_un.res.minvif > vifi)
706				cache->mfc_un.res.minvif = vifi;
707			if (cache->mfc_un.res.maxvif <= vifi)
708				cache->mfc_un.res.maxvif = vifi + 1;
709		}
710	}
711}
712
713static int vif_add(struct net *net, struct mr_table *mrt,
714		   struct vifctl *vifc, int mrtsock)
715{
716	int vifi = vifc->vifc_vifi;
717	struct vif_device *v = &mrt->vif_table[vifi];
718	struct net_device *dev;
719	struct in_device *in_dev;
720	int err;
721
722	/* Is vif busy ? */
723	if (VIF_EXISTS(mrt, vifi))
724		return -EADDRINUSE;
725
726	switch (vifc->vifc_flags) {
727#ifdef CONFIG_IP_PIMSM
728	case VIFF_REGISTER:
729		/*
730		 * Special Purpose VIF in PIM
731		 * All the packets will be sent to the daemon
732		 */
733		if (mrt->mroute_reg_vif_num >= 0)
734			return -EADDRINUSE;
735		dev = ipmr_reg_vif(net, mrt);
736		if (!dev)
737			return -ENOBUFS;
738		err = dev_set_allmulti(dev, 1);
739		if (err) {
740			unregister_netdevice(dev);
741			dev_put(dev);
742			return err;
743		}
744		break;
745#endif
746	case VIFF_TUNNEL:
747		dev = ipmr_new_tunnel(net, vifc);
748		if (!dev)
749			return -ENOBUFS;
750		err = dev_set_allmulti(dev, 1);
751		if (err) {
752			ipmr_del_tunnel(dev, vifc);
753			dev_put(dev);
754			return err;
755		}
756		break;
757
758	case VIFF_USE_IFINDEX:
759	case 0:
760		if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
761			dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
762			if (dev && __in_dev_get_rtnl(dev) == NULL) {
763				dev_put(dev);
764				return -EADDRNOTAVAIL;
765			}
766		} else {
767			dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
768		}
769		if (!dev)
770			return -EADDRNOTAVAIL;
771		err = dev_set_allmulti(dev, 1);
772		if (err) {
773			dev_put(dev);
774			return err;
775		}
776		break;
777	default:
778		return -EINVAL;
779	}
780
781	in_dev = __in_dev_get_rtnl(dev);
782	if (!in_dev) {
783		dev_put(dev);
784		return -EADDRNOTAVAIL;
785	}
786	IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
787	inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING, dev->ifindex,
788				    &in_dev->cnf);
789	ip_rt_multicast_event(in_dev);
790
791	/* Fill in the VIF structures */
792
793	v->rate_limit = vifc->vifc_rate_limit;
794	v->local = vifc->vifc_lcl_addr.s_addr;
795	v->remote = vifc->vifc_rmt_addr.s_addr;
796	v->flags = vifc->vifc_flags;
797	if (!mrtsock)
798		v->flags |= VIFF_STATIC;
799	v->threshold = vifc->vifc_threshold;
800	v->bytes_in = 0;
801	v->bytes_out = 0;
802	v->pkt_in = 0;
803	v->pkt_out = 0;
804	v->link = dev->ifindex;
805	if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER))
806		v->link = dev->iflink;
807
808	/* And finish update writing critical data */
809	write_lock_bh(&mrt_lock);
810	v->dev = dev;
811#ifdef CONFIG_IP_PIMSM
812	if (v->flags & VIFF_REGISTER)
813		mrt->mroute_reg_vif_num = vifi;
814#endif
815	if (vifi+1 > mrt->maxvif)
816		mrt->maxvif = vifi+1;
817	write_unlock_bh(&mrt_lock);
818	return 0;
819}
820
821/* called with rcu_read_lock() */
822static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
823					 __be32 origin,
824					 __be32 mcastgrp)
825{
826	int line = MFC_HASH(mcastgrp, origin);
827	struct mfc_cache *c;
828
829	list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list) {
830		if (c->mfc_origin == origin && c->mfc_mcastgrp == mcastgrp)
831			return c;
832	}
833	return NULL;
834}
835
836/* Look for a (*,*,oif) entry */
837static struct mfc_cache *ipmr_cache_find_any_parent(struct mr_table *mrt,
838						    int vifi)
839{
840	int line = MFC_HASH(htonl(INADDR_ANY), htonl(INADDR_ANY));
841	struct mfc_cache *c;
842
843	list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list)
844		if (c->mfc_origin == htonl(INADDR_ANY) &&
845		    c->mfc_mcastgrp == htonl(INADDR_ANY) &&
846		    c->mfc_un.res.ttls[vifi] < 255)
847			return c;
848
849	return NULL;
850}
851
852/* Look for a (*,G) entry */
853static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
854					     __be32 mcastgrp, int vifi)
855{
856	int line = MFC_HASH(mcastgrp, htonl(INADDR_ANY));
857	struct mfc_cache *c, *proxy;
858
859	if (mcastgrp == htonl(INADDR_ANY))
860		goto skip;
861
862	list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list)
863		if (c->mfc_origin == htonl(INADDR_ANY) &&
864		    c->mfc_mcastgrp == mcastgrp) {
865			if (c->mfc_un.res.ttls[vifi] < 255)
866				return c;
867
868			/* It's ok if the vifi is part of the static tree */
869			proxy = ipmr_cache_find_any_parent(mrt,
870							   c->mfc_parent);
871			if (proxy && proxy->mfc_un.res.ttls[vifi] < 255)
872				return c;
873		}
874
875skip:
876	return ipmr_cache_find_any_parent(mrt, vifi);
877}
878
879/*
880 *	Allocate a multicast cache entry
881 */
882static struct mfc_cache *ipmr_cache_alloc(void)
883{
884	struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
885
886	if (c)
887		c->mfc_un.res.minvif = MAXVIFS;
888	return c;
889}
890
891static struct mfc_cache *ipmr_cache_alloc_unres(void)
892{
893	struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
894
895	if (c) {
896		skb_queue_head_init(&c->mfc_un.unres.unresolved);
897		c->mfc_un.unres.expires = jiffies + 10*HZ;
898	}
899	return c;
900}
901
902/*
903 *	A cache entry has gone into a resolved state from queued
904 */
905
906static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
907			       struct mfc_cache *uc, struct mfc_cache *c)
908{
909	struct sk_buff *skb;
910	struct nlmsgerr *e;
911
912	/* Play the pending entries through our router */
913
914	while ((skb = __skb_dequeue(&uc->mfc_un.unres.unresolved))) {
915		if (ip_hdr(skb)->version == 0) {
916			struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
917
918			if (__ipmr_fill_mroute(mrt, skb, c, nlmsg_data(nlh)) > 0) {
919				nlh->nlmsg_len = skb_tail_pointer(skb) -
920						 (u8 *)nlh;
921			} else {
922				nlh->nlmsg_type = NLMSG_ERROR;
923				nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
924				skb_trim(skb, nlh->nlmsg_len);
925				e = nlmsg_data(nlh);
926				e->error = -EMSGSIZE;
927				memset(&e->msg, 0, sizeof(e->msg));
928			}
929
930			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
931		} else {
932			ip_mr_forward(net, mrt, skb, c, 0);
933		}
934	}
935}
936
937/*
938 *	Bounce a cache query up to mrouted. We could use netlink for this but mrouted
939 *	expects the following bizarre scheme.
940 *
941 *	Called under mrt_lock.
942 */
943
944static int ipmr_cache_report(struct mr_table *mrt,
945			     struct sk_buff *pkt, vifi_t vifi, int assert)
946{
947	struct sk_buff *skb;
948	const int ihl = ip_hdrlen(pkt);
949	struct igmphdr *igmp;
950	struct igmpmsg *msg;
951	struct sock *mroute_sk;
952	int ret;
953
954#ifdef CONFIG_IP_PIMSM
955	if (assert == IGMPMSG_WHOLEPKT)
956		skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
957	else
958#endif
959		skb = alloc_skb(128, GFP_ATOMIC);
960
961	if (!skb)
962		return -ENOBUFS;
963
964#ifdef CONFIG_IP_PIMSM
965	if (assert == IGMPMSG_WHOLEPKT) {
966		/* Ugly, but we have no choice with this interface.
967		 * Duplicate old header, fix ihl, length etc.
968		 * And all this only to mangle msg->im_msgtype and
969		 * to set msg->im_mbz to "mbz" :-)
970		 */
971		skb_push(skb, sizeof(struct iphdr));
972		skb_reset_network_header(skb);
973		skb_reset_transport_header(skb);
974		msg = (struct igmpmsg *)skb_network_header(skb);
975		memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
976		msg->im_msgtype = IGMPMSG_WHOLEPKT;
977		msg->im_mbz = 0;
978		msg->im_vif = mrt->mroute_reg_vif_num;
979		ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
980		ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
981					     sizeof(struct iphdr));
982	} else
983#endif
984	{
985
986	/* Copy the IP header */
987
988	skb_set_network_header(skb, skb->len);
989	skb_put(skb, ihl);
990	skb_copy_to_linear_data(skb, pkt->data, ihl);
991	ip_hdr(skb)->protocol = 0;	/* Flag to the kernel this is a route add */
992	msg = (struct igmpmsg *)skb_network_header(skb);
993	msg->im_vif = vifi;
994	skb_dst_set(skb, dst_clone(skb_dst(pkt)));
995
996	/* Add our header */
997
998	igmp = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
999	igmp->type	=
1000	msg->im_msgtype = assert;
1001	igmp->code	= 0;
1002	ip_hdr(skb)->tot_len = htons(skb->len);		/* Fix the length */
1003	skb->transport_header = skb->network_header;
1004	}
1005
1006	rcu_read_lock();
1007	mroute_sk = rcu_dereference(mrt->mroute_sk);
1008	if (mroute_sk == NULL) {
1009		rcu_read_unlock();
1010		kfree_skb(skb);
1011		return -EINVAL;
1012	}
1013
1014	/* Deliver to mrouted */
1015
1016	ret = sock_queue_rcv_skb(mroute_sk, skb);
1017	rcu_read_unlock();
1018	if (ret < 0) {
1019		net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1020		kfree_skb(skb);
1021	}
1022
1023	return ret;
1024}
1025
1026/*
1027 *	Queue a packet for resolution. It gets locked cache entry!
1028 */
1029
1030static int
1031ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi, struct sk_buff *skb)
1032{
1033	bool found = false;
1034	int err;
1035	struct mfc_cache *c;
1036	const struct iphdr *iph = ip_hdr(skb);
1037
1038	spin_lock_bh(&mfc_unres_lock);
1039	list_for_each_entry(c, &mrt->mfc_unres_queue, list) {
1040		if (c->mfc_mcastgrp == iph->daddr &&
1041		    c->mfc_origin == iph->saddr) {
1042			found = true;
1043			break;
1044		}
1045	}
1046
1047	if (!found) {
1048		/* Create a new entry if allowable */
1049
1050		if (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
1051		    (c = ipmr_cache_alloc_unres()) == NULL) {
1052			spin_unlock_bh(&mfc_unres_lock);
1053
1054			kfree_skb(skb);
1055			return -ENOBUFS;
1056		}
1057
1058		/* Fill in the new cache entry */
1059
1060		c->mfc_parent	= -1;
1061		c->mfc_origin	= iph->saddr;
1062		c->mfc_mcastgrp	= iph->daddr;
1063
1064		/* Reflect first query at mrouted. */
1065
1066		err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1067		if (err < 0) {
1068			/* If the report failed throw the cache entry
1069			   out - Brad Parker
1070			 */
1071			spin_unlock_bh(&mfc_unres_lock);
1072
1073			ipmr_cache_free(c);
1074			kfree_skb(skb);
1075			return err;
1076		}
1077
1078		atomic_inc(&mrt->cache_resolve_queue_len);
1079		list_add(&c->list, &mrt->mfc_unres_queue);
1080		mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1081
1082		if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1083			mod_timer(&mrt->ipmr_expire_timer, c->mfc_un.unres.expires);
1084	}
1085
1086	/* See if we can append the packet */
1087
1088	if (c->mfc_un.unres.unresolved.qlen > 3) {
1089		kfree_skb(skb);
1090		err = -ENOBUFS;
1091	} else {
1092		skb_queue_tail(&c->mfc_un.unres.unresolved, skb);
1093		err = 0;
1094	}
1095
1096	spin_unlock_bh(&mfc_unres_lock);
1097	return err;
1098}
1099
1100/*
1101 *	MFC cache manipulation by user space mroute daemon
1102 */
1103
1104static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1105{
1106	int line;
1107	struct mfc_cache *c, *next;
1108
1109	line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1110
1111	list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[line], list) {
1112		if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1113		    c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr &&
1114		    (parent == -1 || parent == c->mfc_parent)) {
1115			list_del_rcu(&c->list);
1116			mroute_netlink_event(mrt, c, RTM_DELROUTE);
1117			ipmr_cache_free(c);
1118			return 0;
1119		}
1120	}
1121	return -ENOENT;
1122}
1123
1124static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1125			struct mfcctl *mfc, int mrtsock, int parent)
1126{
1127	bool found = false;
1128	int line;
1129	struct mfc_cache *uc, *c;
1130
1131	if (mfc->mfcc_parent >= MAXVIFS)
1132		return -ENFILE;
1133
1134	line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1135
1136	list_for_each_entry(c, &mrt->mfc_cache_array[line], list) {
1137		if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1138		    c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr &&
1139		    (parent == -1 || parent == c->mfc_parent)) {
1140			found = true;
1141			break;
1142		}
1143	}
1144
1145	if (found) {
1146		write_lock_bh(&mrt_lock);
1147		c->mfc_parent = mfc->mfcc_parent;
1148		ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1149		if (!mrtsock)
1150			c->mfc_flags |= MFC_STATIC;
1151		write_unlock_bh(&mrt_lock);
1152		mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1153		return 0;
1154	}
1155
1156	if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1157	    !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1158		return -EINVAL;
1159
1160	c = ipmr_cache_alloc();
1161	if (c == NULL)
1162		return -ENOMEM;
1163
1164	c->mfc_origin = mfc->mfcc_origin.s_addr;
1165	c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1166	c->mfc_parent = mfc->mfcc_parent;
1167	ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1168	if (!mrtsock)
1169		c->mfc_flags |= MFC_STATIC;
1170
1171	list_add_rcu(&c->list, &mrt->mfc_cache_array[line]);
1172
1173	/*
1174	 *	Check to see if we resolved a queued list. If so we
1175	 *	need to send on the frames and tidy up.
1176	 */
1177	found = false;
1178	spin_lock_bh(&mfc_unres_lock);
1179	list_for_each_entry(uc, &mrt->mfc_unres_queue, list) {
1180		if (uc->mfc_origin == c->mfc_origin &&
1181		    uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1182			list_del(&uc->list);
1183			atomic_dec(&mrt->cache_resolve_queue_len);
1184			found = true;
1185			break;
1186		}
1187	}
1188	if (list_empty(&mrt->mfc_unres_queue))
1189		del_timer(&mrt->ipmr_expire_timer);
1190	spin_unlock_bh(&mfc_unres_lock);
1191
1192	if (found) {
1193		ipmr_cache_resolve(net, mrt, uc, c);
1194		ipmr_cache_free(uc);
1195	}
1196	mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1197	return 0;
1198}
1199
1200/*
1201 *	Close the multicast socket, and clear the vif tables etc
1202 */
1203
1204static void mroute_clean_tables(struct mr_table *mrt)
1205{
1206	int i;
1207	LIST_HEAD(list);
1208	struct mfc_cache *c, *next;
1209
1210	/* Shut down all active vif entries */
1211
1212	for (i = 0; i < mrt->maxvif; i++) {
1213		if (!(mrt->vif_table[i].flags & VIFF_STATIC))
1214			vif_delete(mrt, i, 0, &list);
1215	}
1216	unregister_netdevice_many(&list);
1217
1218	/* Wipe the cache */
1219
1220	for (i = 0; i < MFC_LINES; i++) {
1221		list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[i], list) {
1222			if (c->mfc_flags & MFC_STATIC)
1223				continue;
1224			list_del_rcu(&c->list);
1225			mroute_netlink_event(mrt, c, RTM_DELROUTE);
1226			ipmr_cache_free(c);
1227		}
1228	}
1229
1230	if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1231		spin_lock_bh(&mfc_unres_lock);
1232		list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
1233			list_del(&c->list);
1234			mroute_netlink_event(mrt, c, RTM_DELROUTE);
1235			ipmr_destroy_unres(mrt, c);
1236		}
1237		spin_unlock_bh(&mfc_unres_lock);
1238	}
1239}
1240
1241/* called from ip_ra_control(), before an RCU grace period,
1242 * we dont need to call synchronize_rcu() here
1243 */
1244static void mrtsock_destruct(struct sock *sk)
1245{
1246	struct net *net = sock_net(sk);
1247	struct mr_table *mrt;
1248
1249	rtnl_lock();
1250	ipmr_for_each_table(mrt, net) {
1251		if (sk == rtnl_dereference(mrt->mroute_sk)) {
1252			IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1253			inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
1254						    NETCONFA_IFINDEX_ALL,
1255						    net->ipv4.devconf_all);
1256			RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1257			mroute_clean_tables(mrt);
1258		}
1259	}
1260	rtnl_unlock();
1261}
1262
1263/*
1264 *	Socket options and virtual interface manipulation. The whole
1265 *	virtual interface system is a complete heap, but unfortunately
1266 *	that's how BSD mrouted happens to think. Maybe one day with a proper
1267 *	MOSPF/PIM router set up we can clean this up.
1268 */
1269
1270int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsigned int optlen)
1271{
1272	int ret, parent = 0;
1273	struct vifctl vif;
1274	struct mfcctl mfc;
1275	struct net *net = sock_net(sk);
1276	struct mr_table *mrt;
1277
1278	if (sk->sk_type != SOCK_RAW ||
1279	    inet_sk(sk)->inet_num != IPPROTO_IGMP)
1280		return -EOPNOTSUPP;
1281
1282	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1283	if (mrt == NULL)
1284		return -ENOENT;
1285
1286	if (optname != MRT_INIT) {
1287		if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1288		    !ns_capable(net->user_ns, CAP_NET_ADMIN))
1289			return -EACCES;
1290	}
1291
1292	switch (optname) {
1293	case MRT_INIT:
1294		if (optlen != sizeof(int))
1295			return -EINVAL;
1296
1297		rtnl_lock();
1298		if (rtnl_dereference(mrt->mroute_sk)) {
1299			rtnl_unlock();
1300			return -EADDRINUSE;
1301		}
1302
1303		ret = ip_ra_control(sk, 1, mrtsock_destruct);
1304		if (ret == 0) {
1305			rcu_assign_pointer(mrt->mroute_sk, sk);
1306			IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1307			inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
1308						    NETCONFA_IFINDEX_ALL,
1309						    net->ipv4.devconf_all);
1310		}
1311		rtnl_unlock();
1312		return ret;
1313	case MRT_DONE:
1314		if (sk != rcu_access_pointer(mrt->mroute_sk))
1315			return -EACCES;
1316		return ip_ra_control(sk, 0, NULL);
1317	case MRT_ADD_VIF:
1318	case MRT_DEL_VIF:
1319		if (optlen != sizeof(vif))
1320			return -EINVAL;
1321		if (copy_from_user(&vif, optval, sizeof(vif)))
1322			return -EFAULT;
1323		if (vif.vifc_vifi >= MAXVIFS)
1324			return -ENFILE;
1325		rtnl_lock();
1326		if (optname == MRT_ADD_VIF) {
1327			ret = vif_add(net, mrt, &vif,
1328				      sk == rtnl_dereference(mrt->mroute_sk));
1329		} else {
1330			ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1331		}
1332		rtnl_unlock();
1333		return ret;
1334
1335		/*
1336		 *	Manipulate the forwarding caches. These live
1337		 *	in a sort of kernel/user symbiosis.
1338		 */
1339	case MRT_ADD_MFC:
1340	case MRT_DEL_MFC:
1341		parent = -1;
1342	case MRT_ADD_MFC_PROXY:
1343	case MRT_DEL_MFC_PROXY:
1344		if (optlen != sizeof(mfc))
1345			return -EINVAL;
1346		if (copy_from_user(&mfc, optval, sizeof(mfc)))
1347			return -EFAULT;
1348		if (parent == 0)
1349			parent = mfc.mfcc_parent;
1350		rtnl_lock();
1351		if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1352			ret = ipmr_mfc_delete(mrt, &mfc, parent);
1353		else
1354			ret = ipmr_mfc_add(net, mrt, &mfc,
1355					   sk == rtnl_dereference(mrt->mroute_sk),
1356					   parent);
1357		rtnl_unlock();
1358		return ret;
1359		/*
1360		 *	Control PIM assert.
1361		 */
1362	case MRT_ASSERT:
1363	{
1364		int v;
1365		if (optlen != sizeof(v))
1366			return -EINVAL;
1367		if (get_user(v, (int __user *)optval))
1368			return -EFAULT;
1369		mrt->mroute_do_assert = v;
1370		return 0;
1371	}
1372#ifdef CONFIG_IP_PIMSM
1373	case MRT_PIM:
1374	{
1375		int v;
1376
1377		if (optlen != sizeof(v))
1378			return -EINVAL;
1379		if (get_user(v, (int __user *)optval))
1380			return -EFAULT;
1381		v = !!v;
1382
1383		rtnl_lock();
1384		ret = 0;
1385		if (v != mrt->mroute_do_pim) {
1386			mrt->mroute_do_pim = v;
1387			mrt->mroute_do_assert = v;
1388		}
1389		rtnl_unlock();
1390		return ret;
1391	}
1392#endif
1393#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
1394	case MRT_TABLE:
1395	{
1396		u32 v;
1397
1398		if (optlen != sizeof(u32))
1399			return -EINVAL;
1400		if (get_user(v, (u32 __user *)optval))
1401			return -EFAULT;
1402
1403		/* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) */
1404		if (v != RT_TABLE_DEFAULT && v >= 1000000000)
1405			return -EINVAL;
1406
1407		rtnl_lock();
1408		ret = 0;
1409		if (sk == rtnl_dereference(mrt->mroute_sk)) {
1410			ret = -EBUSY;
1411		} else {
1412			if (!ipmr_new_table(net, v))
1413				ret = -ENOMEM;
1414			else
1415				raw_sk(sk)->ipmr_table = v;
1416		}
1417		rtnl_unlock();
1418		return ret;
1419	}
1420#endif
1421	/*
1422	 *	Spurious command, or MRT_VERSION which you cannot
1423	 *	set.
1424	 */
1425	default:
1426		return -ENOPROTOOPT;
1427	}
1428}
1429
1430/*
1431 *	Getsock opt support for the multicast routing system.
1432 */
1433
1434int ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen)
1435{
1436	int olr;
1437	int val;
1438	struct net *net = sock_net(sk);
1439	struct mr_table *mrt;
1440
1441	if (sk->sk_type != SOCK_RAW ||
1442	    inet_sk(sk)->inet_num != IPPROTO_IGMP)
1443		return -EOPNOTSUPP;
1444
1445	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1446	if (mrt == NULL)
1447		return -ENOENT;
1448
1449	if (optname != MRT_VERSION &&
1450#ifdef CONFIG_IP_PIMSM
1451	   optname != MRT_PIM &&
1452#endif
1453	   optname != MRT_ASSERT)
1454		return -ENOPROTOOPT;
1455
1456	if (get_user(olr, optlen))
1457		return -EFAULT;
1458
1459	olr = min_t(unsigned int, olr, sizeof(int));
1460	if (olr < 0)
1461		return -EINVAL;
1462
1463	if (put_user(olr, optlen))
1464		return -EFAULT;
1465	if (optname == MRT_VERSION)
1466		val = 0x0305;
1467#ifdef CONFIG_IP_PIMSM
1468	else if (optname == MRT_PIM)
1469		val = mrt->mroute_do_pim;
1470#endif
1471	else
1472		val = mrt->mroute_do_assert;
1473	if (copy_to_user(optval, &val, olr))
1474		return -EFAULT;
1475	return 0;
1476}
1477
1478/*
1479 *	The IP multicast ioctl support routines.
1480 */
1481
1482int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
1483{
1484	struct sioc_sg_req sr;
1485	struct sioc_vif_req vr;
1486	struct vif_device *vif;
1487	struct mfc_cache *c;
1488	struct net *net = sock_net(sk);
1489	struct mr_table *mrt;
1490
1491	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1492	if (mrt == NULL)
1493		return -ENOENT;
1494
1495	switch (cmd) {
1496	case SIOCGETVIFCNT:
1497		if (copy_from_user(&vr, arg, sizeof(vr)))
1498			return -EFAULT;
1499		if (vr.vifi >= mrt->maxvif)
1500			return -EINVAL;
1501		read_lock(&mrt_lock);
1502		vif = &mrt->vif_table[vr.vifi];
1503		if (VIF_EXISTS(mrt, vr.vifi)) {
1504			vr.icount = vif->pkt_in;
1505			vr.ocount = vif->pkt_out;
1506			vr.ibytes = vif->bytes_in;
1507			vr.obytes = vif->bytes_out;
1508			read_unlock(&mrt_lock);
1509
1510			if (copy_to_user(arg, &vr, sizeof(vr)))
1511				return -EFAULT;
1512			return 0;
1513		}
1514		read_unlock(&mrt_lock);
1515		return -EADDRNOTAVAIL;
1516	case SIOCGETSGCNT:
1517		if (copy_from_user(&sr, arg, sizeof(sr)))
1518			return -EFAULT;
1519
1520		rcu_read_lock();
1521		c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1522		if (c) {
1523			sr.pktcnt = c->mfc_un.res.pkt;
1524			sr.bytecnt = c->mfc_un.res.bytes;
1525			sr.wrong_if = c->mfc_un.res.wrong_if;
1526			rcu_read_unlock();
1527
1528			if (copy_to_user(arg, &sr, sizeof(sr)))
1529				return -EFAULT;
1530			return 0;
1531		}
1532		rcu_read_unlock();
1533		return -EADDRNOTAVAIL;
1534	default:
1535		return -ENOIOCTLCMD;
1536	}
1537}
1538
1539#ifdef CONFIG_COMPAT
1540struct compat_sioc_sg_req {
1541	struct in_addr src;
1542	struct in_addr grp;
1543	compat_ulong_t pktcnt;
1544	compat_ulong_t bytecnt;
1545	compat_ulong_t wrong_if;
1546};
1547
1548struct compat_sioc_vif_req {
1549	vifi_t	vifi;		/* Which iface */
1550	compat_ulong_t icount;
1551	compat_ulong_t ocount;
1552	compat_ulong_t ibytes;
1553	compat_ulong_t obytes;
1554};
1555
1556int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1557{
1558	struct compat_sioc_sg_req sr;
1559	struct compat_sioc_vif_req vr;
1560	struct vif_device *vif;
1561	struct mfc_cache *c;
1562	struct net *net = sock_net(sk);
1563	struct mr_table *mrt;
1564
1565	mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1566	if (mrt == NULL)
1567		return -ENOENT;
1568
1569	switch (cmd) {
1570	case SIOCGETVIFCNT:
1571		if (copy_from_user(&vr, arg, sizeof(vr)))
1572			return -EFAULT;
1573		if (vr.vifi >= mrt->maxvif)
1574			return -EINVAL;
1575		read_lock(&mrt_lock);
1576		vif = &mrt->vif_table[vr.vifi];
1577		if (VIF_EXISTS(mrt, vr.vifi)) {
1578			vr.icount = vif->pkt_in;
1579			vr.ocount = vif->pkt_out;
1580			vr.ibytes = vif->bytes_in;
1581			vr.obytes = vif->bytes_out;
1582			read_unlock(&mrt_lock);
1583
1584			if (copy_to_user(arg, &vr, sizeof(vr)))
1585				return -EFAULT;
1586			return 0;
1587		}
1588		read_unlock(&mrt_lock);
1589		return -EADDRNOTAVAIL;
1590	case SIOCGETSGCNT:
1591		if (copy_from_user(&sr, arg, sizeof(sr)))
1592			return -EFAULT;
1593
1594		rcu_read_lock();
1595		c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1596		if (c) {
1597			sr.pktcnt = c->mfc_un.res.pkt;
1598			sr.bytecnt = c->mfc_un.res.bytes;
1599			sr.wrong_if = c->mfc_un.res.wrong_if;
1600			rcu_read_unlock();
1601
1602			if (copy_to_user(arg, &sr, sizeof(sr)))
1603				return -EFAULT;
1604			return 0;
1605		}
1606		rcu_read_unlock();
1607		return -EADDRNOTAVAIL;
1608	default:
1609		return -ENOIOCTLCMD;
1610	}
1611}
1612#endif
1613
1614
1615static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1616{
1617	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1618	struct net *net = dev_net(dev);
1619	struct mr_table *mrt;
1620	struct vif_device *v;
1621	int ct;
1622
1623	if (event != NETDEV_UNREGISTER)
1624		return NOTIFY_DONE;
1625
1626	ipmr_for_each_table(mrt, net) {
1627		v = &mrt->vif_table[0];
1628		for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1629			if (v->dev == dev)
1630				vif_delete(mrt, ct, 1, NULL);
1631		}
1632	}
1633	return NOTIFY_DONE;
1634}
1635
1636
1637static struct notifier_block ip_mr_notifier = {
1638	.notifier_call = ipmr_device_event,
1639};
1640
1641/*
1642 *	Encapsulate a packet by attaching a valid IPIP header to it.
1643 *	This avoids tunnel drivers and other mess and gives us the speed so
1644 *	important for multicast video.
1645 */
1646
1647static void ip_encap(struct sk_buff *skb, __be32 saddr, __be32 daddr)
1648{
1649	struct iphdr *iph;
1650	const struct iphdr *old_iph = ip_hdr(skb);
1651
1652	skb_push(skb, sizeof(struct iphdr));
1653	skb->transport_header = skb->network_header;
1654	skb_reset_network_header(skb);
1655	iph = ip_hdr(skb);
1656
1657	iph->version	=	4;
1658	iph->tos	=	old_iph->tos;
1659	iph->ttl	=	old_iph->ttl;
1660	iph->frag_off	=	0;
1661	iph->daddr	=	daddr;
1662	iph->saddr	=	saddr;
1663	iph->protocol	=	IPPROTO_IPIP;
1664	iph->ihl	=	5;
1665	iph->tot_len	=	htons(skb->len);
1666	ip_select_ident(skb, NULL);
1667	ip_send_check(iph);
1668
1669	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1670	nf_reset(skb);
1671}
1672
1673static inline int ipmr_forward_finish(struct sk_buff *skb)
1674{
1675	struct ip_options *opt = &(IPCB(skb)->opt);
1676
1677	IP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTFORWDATAGRAMS);
1678	IP_ADD_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTOCTETS, skb->len);
1679
1680	if (unlikely(opt->optlen))
1681		ip_forward_options(skb);
1682
1683	return dst_output(skb);
1684}
1685
1686/*
1687 *	Processing handlers for ipmr_forward
1688 */
1689
1690static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1691			    struct sk_buff *skb, struct mfc_cache *c, int vifi)
1692{
1693	const struct iphdr *iph = ip_hdr(skb);
1694	struct vif_device *vif = &mrt->vif_table[vifi];
1695	struct net_device *dev;
1696	struct rtable *rt;
1697	struct flowi4 fl4;
1698	int    encap = 0;
1699
1700	if (vif->dev == NULL)
1701		goto out_free;
1702
1703#ifdef CONFIG_IP_PIMSM
1704	if (vif->flags & VIFF_REGISTER) {
1705		vif->pkt_out++;
1706		vif->bytes_out += skb->len;
1707		vif->dev->stats.tx_bytes += skb->len;
1708		vif->dev->stats.tx_packets++;
1709		ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1710		goto out_free;
1711	}
1712#endif
1713
1714	if (vif->flags & VIFF_TUNNEL) {
1715		rt = ip_route_output_ports(net, &fl4, NULL,
1716					   vif->remote, vif->local,
1717					   0, 0,
1718					   IPPROTO_IPIP,
1719					   RT_TOS(iph->tos), vif->link);
1720		if (IS_ERR(rt))
1721			goto out_free;
1722		encap = sizeof(struct iphdr);
1723	} else {
1724		rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1725					   0, 0,
1726					   IPPROTO_IPIP,
1727					   RT_TOS(iph->tos), vif->link);
1728		if (IS_ERR(rt))
1729			goto out_free;
1730	}
1731
1732	dev = rt->dst.dev;
1733
1734	if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1735		/* Do not fragment multicasts. Alas, IPv4 does not
1736		 * allow to send ICMP, so that packets will disappear
1737		 * to blackhole.
1738		 */
1739
1740		IP_INC_STATS_BH(dev_net(dev), IPSTATS_MIB_FRAGFAILS);
1741		ip_rt_put(rt);
1742		goto out_free;
1743	}
1744
1745	encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1746
1747	if (skb_cow(skb, encap)) {
1748		ip_rt_put(rt);
1749		goto out_free;
1750	}
1751
1752	vif->pkt_out++;
1753	vif->bytes_out += skb->len;
1754
1755	skb_dst_drop(skb);
1756	skb_dst_set(skb, &rt->dst);
1757	ip_decrease_ttl(ip_hdr(skb));
1758
1759	/* FIXME: forward and output firewalls used to be called here.
1760	 * What do we do with netfilter? -- RR
1761	 */
1762	if (vif->flags & VIFF_TUNNEL) {
1763		ip_encap(skb, vif->local, vif->remote);
1764		/* FIXME: extra output firewall step used to be here. --RR */
1765		vif->dev->stats.tx_packets++;
1766		vif->dev->stats.tx_bytes += skb->len;
1767	}
1768
1769	IPCB(skb)->flags |= IPSKB_FORWARDED;
1770
1771	/*
1772	 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1773	 * not only before forwarding, but after forwarding on all output
1774	 * interfaces. It is clear, if mrouter runs a multicasting
1775	 * program, it should receive packets not depending to what interface
1776	 * program is joined.
1777	 * If we will not make it, the program will have to join on all
1778	 * interfaces. On the other hand, multihoming host (or router, but
1779	 * not mrouter) cannot join to more than one interface - it will
1780	 * result in receiving multiple packets.
1781	 */
1782	NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD, skb, skb->dev, dev,
1783		ipmr_forward_finish);
1784	return;
1785
1786out_free:
1787	kfree_skb(skb);
1788}
1789
1790static int ipmr_find_vif(struct mr_table *mrt, struct net_device *dev)
1791{
1792	int ct;
1793
1794	for (ct = mrt->maxvif-1; ct >= 0; ct--) {
1795		if (mrt->vif_table[ct].dev == dev)
1796			break;
1797	}
1798	return ct;
1799}
1800
1801/* "local" means that we should preserve one skb (for local delivery) */
1802
1803static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1804			  struct sk_buff *skb, struct mfc_cache *cache,
1805			  int local)
1806{
1807	int psend = -1;
1808	int vif, ct;
1809	int true_vifi = ipmr_find_vif(mrt, skb->dev);
1810
1811	vif = cache->mfc_parent;
1812	cache->mfc_un.res.pkt++;
1813	cache->mfc_un.res.bytes += skb->len;
1814
1815	if (cache->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1816		struct mfc_cache *cache_proxy;
1817
1818		/* For an (*,G) entry, we only check that the incomming
1819		 * interface is part of the static tree.
1820		 */
1821		cache_proxy = ipmr_cache_find_any_parent(mrt, vif);
1822		if (cache_proxy &&
1823		    cache_proxy->mfc_un.res.ttls[true_vifi] < 255)
1824			goto forward;
1825	}
1826
1827	/*
1828	 * Wrong interface: drop packet and (maybe) send PIM assert.
1829	 */
1830	if (mrt->vif_table[vif].dev != skb->dev) {
1831		if (rt_is_output_route(skb_rtable(skb))) {
1832			/* It is our own packet, looped back.
1833			 * Very complicated situation...
1834			 *
1835			 * The best workaround until routing daemons will be
1836			 * fixed is not to redistribute packet, if it was
1837			 * send through wrong interface. It means, that
1838			 * multicast applications WILL NOT work for
1839			 * (S,G), which have default multicast route pointing
1840			 * to wrong oif. In any case, it is not a good
1841			 * idea to use multicasting applications on router.
1842			 */
1843			goto dont_forward;
1844		}
1845
1846		cache->mfc_un.res.wrong_if++;
1847
1848		if (true_vifi >= 0 && mrt->mroute_do_assert &&
1849		    /* pimsm uses asserts, when switching from RPT to SPT,
1850		     * so that we cannot check that packet arrived on an oif.
1851		     * It is bad, but otherwise we would need to move pretty
1852		     * large chunk of pimd to kernel. Ough... --ANK
1853		     */
1854		    (mrt->mroute_do_pim ||
1855		     cache->mfc_un.res.ttls[true_vifi] < 255) &&
1856		    time_after(jiffies,
1857			       cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) {
1858			cache->mfc_un.res.last_assert = jiffies;
1859			ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
1860		}
1861		goto dont_forward;
1862	}
1863
1864forward:
1865	mrt->vif_table[vif].pkt_in++;
1866	mrt->vif_table[vif].bytes_in += skb->len;
1867
1868	/*
1869	 *	Forward the frame
1870	 */
1871	if (cache->mfc_origin == htonl(INADDR_ANY) &&
1872	    cache->mfc_mcastgrp == htonl(INADDR_ANY)) {
1873		if (true_vifi >= 0 &&
1874		    true_vifi != cache->mfc_parent &&
1875		    ip_hdr(skb)->ttl >
1876				cache->mfc_un.res.ttls[cache->mfc_parent]) {
1877			/* It's an (*,*) entry and the packet is not coming from
1878			 * the upstream: forward the packet to the upstream
1879			 * only.
1880			 */
1881			psend = cache->mfc_parent;
1882			goto last_forward;
1883		}
1884		goto dont_forward;
1885	}
1886	for (ct = cache->mfc_un.res.maxvif - 1;
1887	     ct >= cache->mfc_un.res.minvif; ct--) {
1888		/* For (*,G) entry, don't forward to the incoming interface */
1889		if ((cache->mfc_origin != htonl(INADDR_ANY) ||
1890		     ct != true_vifi) &&
1891		    ip_hdr(skb)->ttl > cache->mfc_un.res.ttls[ct]) {
1892			if (psend != -1) {
1893				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1894
1895				if (skb2)
1896					ipmr_queue_xmit(net, mrt, skb2, cache,
1897							psend);
1898			}
1899			psend = ct;
1900		}
1901	}
1902last_forward:
1903	if (psend != -1) {
1904		if (local) {
1905			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1906
1907			if (skb2)
1908				ipmr_queue_xmit(net, mrt, skb2, cache, psend);
1909		} else {
1910			ipmr_queue_xmit(net, mrt, skb, cache, psend);
1911			return;
1912		}
1913	}
1914
1915dont_forward:
1916	if (!local)
1917		kfree_skb(skb);
1918}
1919
1920static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
1921{
1922	struct rtable *rt = skb_rtable(skb);
1923	struct iphdr *iph = ip_hdr(skb);
1924	struct flowi4 fl4 = {
1925		.daddr = iph->daddr,
1926		.saddr = iph->saddr,
1927		.flowi4_tos = RT_TOS(iph->tos),
1928		.flowi4_oif = (rt_is_output_route(rt) ?
1929			       skb->dev->ifindex : 0),
1930		.flowi4_iif = (rt_is_output_route(rt) ?
1931			       LOOPBACK_IFINDEX :
1932			       skb->dev->ifindex),
1933		.flowi4_mark = skb->mark,
1934	};
1935	struct mr_table *mrt;
1936	int err;
1937
1938	err = ipmr_fib_lookup(net, &fl4, &mrt);
1939	if (err)
1940		return ERR_PTR(err);
1941	return mrt;
1942}
1943
1944/*
1945 *	Multicast packets for forwarding arrive here
1946 *	Called with rcu_read_lock();
1947 */
1948
1949int ip_mr_input(struct sk_buff *skb)
1950{
1951	struct mfc_cache *cache;
1952	struct net *net = dev_net(skb->dev);
1953	int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
1954	struct mr_table *mrt;
1955
1956	/* Packet is looped back after forward, it should not be
1957	 * forwarded second time, but still can be delivered locally.
1958	 */
1959	if (IPCB(skb)->flags & IPSKB_FORWARDED)
1960		goto dont_forward;
1961
1962	mrt = ipmr_rt_fib_lookup(net, skb);
1963	if (IS_ERR(mrt)) {
1964		kfree_skb(skb);
1965		return PTR_ERR(mrt);
1966	}
1967	if (!local) {
1968		if (IPCB(skb)->opt.router_alert) {
1969			if (ip_call_ra_chain(skb))
1970				return 0;
1971		} else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
1972			/* IGMPv1 (and broken IGMPv2 implementations sort of
1973			 * Cisco IOS <= 11.2(8)) do not put router alert
1974			 * option to IGMP packets destined to routable
1975			 * groups. It is very bad, because it means
1976			 * that we can forward NO IGMP messages.
1977			 */
1978			struct sock *mroute_sk;
1979
1980			mroute_sk = rcu_dereference(mrt->mroute_sk);
1981			if (mroute_sk) {
1982				nf_reset(skb);
1983				raw_rcv(mroute_sk, skb);
1984				return 0;
1985			}
1986		    }
1987	}
1988
1989	/* already under rcu_read_lock() */
1990	cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
1991	if (cache == NULL) {
1992		int vif = ipmr_find_vif(mrt, skb->dev);
1993
1994		if (vif >= 0)
1995			cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
1996						    vif);
1997	}
1998
1999	/*
2000	 *	No usable cache entry
2001	 */
2002	if (cache == NULL) {
2003		int vif;
2004
2005		if (local) {
2006			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2007			ip_local_deliver(skb);
2008			if (skb2 == NULL)
2009				return -ENOBUFS;
2010			skb = skb2;
2011		}
2012
2013		read_lock(&mrt_lock);
2014		vif = ipmr_find_vif(mrt, skb->dev);
2015		if (vif >= 0) {
2016			int err2 = ipmr_cache_unresolved(mrt, vif, skb);
2017			read_unlock(&mrt_lock);
2018
2019			return err2;
2020		}
2021		read_unlock(&mrt_lock);
2022		kfree_skb(skb);
2023		return -ENODEV;
2024	}
2025
2026	read_lock(&mrt_lock);
2027	ip_mr_forward(net, mrt, skb, cache, local);
2028	read_unlock(&mrt_lock);
2029
2030	if (local)
2031		return ip_local_deliver(skb);
2032
2033	return 0;
2034
2035dont_forward:
2036	if (local)
2037		return ip_local_deliver(skb);
2038	kfree_skb(skb);
2039	return 0;
2040}
2041
2042#ifdef CONFIG_IP_PIMSM
2043/* called with rcu_read_lock() */
2044static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
2045		     unsigned int pimlen)
2046{
2047	struct net_device *reg_dev = NULL;
2048	struct iphdr *encap;
2049
2050	encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
2051	/*
2052	 * Check that:
2053	 * a. packet is really sent to a multicast group
2054	 * b. packet is not a NULL-REGISTER
2055	 * c. packet is not truncated
2056	 */
2057	if (!ipv4_is_multicast(encap->daddr) ||
2058	    encap->tot_len == 0 ||
2059	    ntohs(encap->tot_len) + pimlen > skb->len)
2060		return 1;
2061
2062	read_lock(&mrt_lock);
2063	if (mrt->mroute_reg_vif_num >= 0)
2064		reg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
2065	read_unlock(&mrt_lock);
2066
2067	if (reg_dev == NULL)
2068		return 1;
2069
2070	skb->mac_header = skb->network_header;
2071	skb_pull(skb, (u8 *)encap - skb->data);
2072	skb_reset_network_header(skb);
2073	skb->protocol = htons(ETH_P_IP);
2074	skb->ip_summed = CHECKSUM_NONE;
2075
2076	skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
2077
2078	netif_rx(skb);
2079
2080	return NET_RX_SUCCESS;
2081}
2082#endif
2083
2084#ifdef CONFIG_IP_PIMSM_V1
2085/*
2086 * Handle IGMP messages of PIMv1
2087 */
2088
2089int pim_rcv_v1(struct sk_buff *skb)
2090{
2091	struct igmphdr *pim;
2092	struct net *net = dev_net(skb->dev);
2093	struct mr_table *mrt;
2094
2095	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2096		goto drop;
2097
2098	pim = igmp_hdr(skb);
2099
2100	mrt = ipmr_rt_fib_lookup(net, skb);
2101	if (IS_ERR(mrt))
2102		goto drop;
2103	if (!mrt->mroute_do_pim ||
2104	    pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
2105		goto drop;
2106
2107	if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2108drop:
2109		kfree_skb(skb);
2110	}
2111	return 0;
2112}
2113#endif
2114
2115#ifdef CONFIG_IP_PIMSM_V2
2116static int pim_rcv(struct sk_buff *skb)
2117{
2118	struct pimreghdr *pim;
2119	struct net *net = dev_net(skb->dev);
2120	struct mr_table *mrt;
2121
2122	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2123		goto drop;
2124
2125	pim = (struct pimreghdr *)skb_transport_header(skb);
2126	if (pim->type != ((PIM_VERSION << 4) | (PIM_REGISTER)) ||
2127	    (pim->flags & PIM_NULL_REGISTER) ||
2128	    (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
2129	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
2130		goto drop;
2131
2132	mrt = ipmr_rt_fib_lookup(net, skb);
2133	if (IS_ERR(mrt))
2134		goto drop;
2135	if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2136drop:
2137		kfree_skb(skb);
2138	}
2139	return 0;
2140}
2141#endif
2142
2143static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2144			      struct mfc_cache *c, struct rtmsg *rtm)
2145{
2146	int ct;
2147	struct rtnexthop *nhp;
2148	struct nlattr *mp_attr;
2149	struct rta_mfc_stats mfcs;
2150
2151	/* If cache is unresolved, don't try to parse IIF and OIF */
2152	if (c->mfc_parent >= MAXVIFS)
2153		return -ENOENT;
2154
2155	if (VIF_EXISTS(mrt, c->mfc_parent) &&
2156	    nla_put_u32(skb, RTA_IIF, mrt->vif_table[c->mfc_parent].dev->ifindex) < 0)
2157		return -EMSGSIZE;
2158
2159	if (!(mp_attr = nla_nest_start(skb, RTA_MULTIPATH)))
2160		return -EMSGSIZE;
2161
2162	for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
2163		if (VIF_EXISTS(mrt, ct) && c->mfc_un.res.ttls[ct] < 255) {
2164			if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp)))) {
2165				nla_nest_cancel(skb, mp_attr);
2166				return -EMSGSIZE;
2167			}
2168
2169			nhp->rtnh_flags = 0;
2170			nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
2171			nhp->rtnh_ifindex = mrt->vif_table[ct].dev->ifindex;
2172			nhp->rtnh_len = sizeof(*nhp);
2173		}
2174	}
2175
2176	nla_nest_end(skb, mp_attr);
2177
2178	mfcs.mfcs_packets = c->mfc_un.res.pkt;
2179	mfcs.mfcs_bytes = c->mfc_un.res.bytes;
2180	mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
2181	if (nla_put(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs) < 0)
2182		return -EMSGSIZE;
2183
2184	rtm->rtm_type = RTN_MULTICAST;
2185	return 1;
2186}
2187
2188int ipmr_get_route(struct net *net, struct sk_buff *skb,
2189		   __be32 saddr, __be32 daddr,
2190		   struct rtmsg *rtm, int nowait)
2191{
2192	struct mfc_cache *cache;
2193	struct mr_table *mrt;
2194	int err;
2195
2196	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2197	if (mrt == NULL)
2198		return -ENOENT;
2199
2200	rcu_read_lock();
2201	cache = ipmr_cache_find(mrt, saddr, daddr);
2202	if (cache == NULL && skb->dev) {
2203		int vif = ipmr_find_vif(mrt, skb->dev);
2204
2205		if (vif >= 0)
2206			cache = ipmr_cache_find_any(mrt, daddr, vif);
2207	}
2208	if (cache == NULL) {
2209		struct sk_buff *skb2;
2210		struct iphdr *iph;
2211		struct net_device *dev;
2212		int vif = -1;
2213
2214		if (nowait) {
2215			rcu_read_unlock();
2216			return -EAGAIN;
2217		}
2218
2219		dev = skb->dev;
2220		read_lock(&mrt_lock);
2221		if (dev)
2222			vif = ipmr_find_vif(mrt, dev);
2223		if (vif < 0) {
2224			read_unlock(&mrt_lock);
2225			rcu_read_unlock();
2226			return -ENODEV;
2227		}
2228		skb2 = skb_clone(skb, GFP_ATOMIC);
2229		if (!skb2) {
2230			read_unlock(&mrt_lock);
2231			rcu_read_unlock();
2232			return -ENOMEM;
2233		}
2234
2235		skb_push(skb2, sizeof(struct iphdr));
2236		skb_reset_network_header(skb2);
2237		iph = ip_hdr(skb2);
2238		iph->ihl = sizeof(struct iphdr) >> 2;
2239		iph->saddr = saddr;
2240		iph->daddr = daddr;
2241		iph->version = 0;
2242		err = ipmr_cache_unresolved(mrt, vif, skb2);
2243		read_unlock(&mrt_lock);
2244		rcu_read_unlock();
2245		return err;
2246	}
2247
2248	read_lock(&mrt_lock);
2249	if (!nowait && (rtm->rtm_flags & RTM_F_NOTIFY))
2250		cache->mfc_flags |= MFC_NOTIFY;
2251	err = __ipmr_fill_mroute(mrt, skb, cache, rtm);
2252	read_unlock(&mrt_lock);
2253	rcu_read_unlock();
2254	return err;
2255}
2256
2257static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2258			    u32 portid, u32 seq, struct mfc_cache *c, int cmd,
2259			    int flags)
2260{
2261	struct nlmsghdr *nlh;
2262	struct rtmsg *rtm;
2263	int err;
2264
2265	nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2266	if (nlh == NULL)
2267		return -EMSGSIZE;
2268
2269	rtm = nlmsg_data(nlh);
2270	rtm->rtm_family   = RTNL_FAMILY_IPMR;
2271	rtm->rtm_dst_len  = 32;
2272	rtm->rtm_src_len  = 32;
2273	rtm->rtm_tos      = 0;
2274	rtm->rtm_table    = mrt->id;
2275	if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2276		goto nla_put_failure;
2277	rtm->rtm_type     = RTN_MULTICAST;
2278	rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2279	if (c->mfc_flags & MFC_STATIC)
2280		rtm->rtm_protocol = RTPROT_STATIC;
2281	else
2282		rtm->rtm_protocol = RTPROT_MROUTED;
2283	rtm->rtm_flags    = 0;
2284
2285	if (nla_put_be32(skb, RTA_SRC, c->mfc_origin) ||
2286	    nla_put_be32(skb, RTA_DST, c->mfc_mcastgrp))
2287		goto nla_put_failure;
2288	err = __ipmr_fill_mroute(mrt, skb, c, rtm);
2289	/* do not break the dump if cache is unresolved */
2290	if (err < 0 && err != -ENOENT)
2291		goto nla_put_failure;
2292
2293	return nlmsg_end(skb, nlh);
2294
2295nla_put_failure:
2296	nlmsg_cancel(skb, nlh);
2297	return -EMSGSIZE;
2298}
2299
2300static size_t mroute_msgsize(bool unresolved, int maxvif)
2301{
2302	size_t len =
2303		NLMSG_ALIGN(sizeof(struct rtmsg))
2304		+ nla_total_size(4)	/* RTA_TABLE */
2305		+ nla_total_size(4)	/* RTA_SRC */
2306		+ nla_total_size(4)	/* RTA_DST */
2307		;
2308
2309	if (!unresolved)
2310		len = len
2311		      + nla_total_size(4)	/* RTA_IIF */
2312		      + nla_total_size(0)	/* RTA_MULTIPATH */
2313		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2314						/* RTA_MFC_STATS */
2315		      + nla_total_size(sizeof(struct rta_mfc_stats))
2316		;
2317
2318	return len;
2319}
2320
2321static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2322				 int cmd)
2323{
2324	struct net *net = read_pnet(&mrt->net);
2325	struct sk_buff *skb;
2326	int err = -ENOBUFS;
2327
2328	skb = nlmsg_new(mroute_msgsize(mfc->mfc_parent >= MAXVIFS, mrt->maxvif),
2329			GFP_ATOMIC);
2330	if (skb == NULL)
2331		goto errout;
2332
2333	err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2334	if (err < 0)
2335		goto errout;
2336
2337	rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2338	return;
2339
2340errout:
2341	kfree_skb(skb);
2342	if (err < 0)
2343		rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
2344}
2345
2346static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2347{
2348	struct net *net = sock_net(skb->sk);
2349	struct mr_table *mrt;
2350	struct mfc_cache *mfc;
2351	unsigned int t = 0, s_t;
2352	unsigned int h = 0, s_h;
2353	unsigned int e = 0, s_e;
2354
2355	s_t = cb->args[0];
2356	s_h = cb->args[1];
2357	s_e = cb->args[2];
2358
2359	rcu_read_lock();
2360	ipmr_for_each_table(mrt, net) {
2361		if (t < s_t)
2362			goto next_table;
2363		if (t > s_t)
2364			s_h = 0;
2365		for (h = s_h; h < MFC_LINES; h++) {
2366			list_for_each_entry_rcu(mfc, &mrt->mfc_cache_array[h], list) {
2367				if (e < s_e)
2368					goto next_entry;
2369				if (ipmr_fill_mroute(mrt, skb,
2370						     NETLINK_CB(cb->skb).portid,
2371						     cb->nlh->nlmsg_seq,
2372						     mfc, RTM_NEWROUTE,
2373						     NLM_F_MULTI) < 0)
2374					goto done;
2375next_entry:
2376				e++;
2377			}
2378			e = s_e = 0;
2379		}
2380		spin_lock_bh(&mfc_unres_lock);
2381		list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) {
2382			if (e < s_e)
2383				goto next_entry2;
2384			if (ipmr_fill_mroute(mrt, skb,
2385					     NETLINK_CB(cb->skb).portid,
2386					     cb->nlh->nlmsg_seq,
2387					     mfc, RTM_NEWROUTE,
2388					     NLM_F_MULTI) < 0) {
2389				spin_unlock_bh(&mfc_unres_lock);
2390				goto done;
2391			}
2392next_entry2:
2393			e++;
2394		}
2395		spin_unlock_bh(&mfc_unres_lock);
2396		e = s_e = 0;
2397		s_h = 0;
2398next_table:
2399		t++;
2400	}
2401done:
2402	rcu_read_unlock();
2403
2404	cb->args[2] = e;
2405	cb->args[1] = h;
2406	cb->args[0] = t;
2407
2408	return skb->len;
2409}
2410
2411#ifdef CONFIG_PROC_FS
2412/*
2413 *	The /proc interfaces to multicast routing :
2414 *	/proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2415 */
2416struct ipmr_vif_iter {
2417	struct seq_net_private p;
2418	struct mr_table *mrt;
2419	int ct;
2420};
2421
2422static struct vif_device *ipmr_vif_seq_idx(struct net *net,
2423					   struct ipmr_vif_iter *iter,
2424					   loff_t pos)
2425{
2426	struct mr_table *mrt = iter->mrt;
2427
2428	for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
2429		if (!VIF_EXISTS(mrt, iter->ct))
2430			continue;
2431		if (pos-- == 0)
2432			return &mrt->vif_table[iter->ct];
2433	}
2434	return NULL;
2435}
2436
2437static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2438	__acquires(mrt_lock)
2439{
2440	struct ipmr_vif_iter *iter = seq->private;
2441	struct net *net = seq_file_net(seq);
2442	struct mr_table *mrt;
2443
2444	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2445	if (mrt == NULL)
2446		return ERR_PTR(-ENOENT);
2447
2448	iter->mrt = mrt;
2449
2450	read_lock(&mrt_lock);
2451	return *pos ? ipmr_vif_seq_idx(net, seq->private, *pos - 1)
2452		: SEQ_START_TOKEN;
2453}
2454
2455static void *ipmr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2456{
2457	struct ipmr_vif_iter *iter = seq->private;
2458	struct net *net = seq_file_net(seq);
2459	struct mr_table *mrt = iter->mrt;
2460
2461	++*pos;
2462	if (v == SEQ_START_TOKEN)
2463		return ipmr_vif_seq_idx(net, iter, 0);
2464
2465	while (++iter->ct < mrt->maxvif) {
2466		if (!VIF_EXISTS(mrt, iter->ct))
2467			continue;
2468		return &mrt->vif_table[iter->ct];
2469	}
2470	return NULL;
2471}
2472
2473static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2474	__releases(mrt_lock)
2475{
2476	read_unlock(&mrt_lock);
2477}
2478
2479static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2480{
2481	struct ipmr_vif_iter *iter = seq->private;
2482	struct mr_table *mrt = iter->mrt;
2483
2484	if (v == SEQ_START_TOKEN) {
2485		seq_puts(seq,
2486			 "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
2487	} else {
2488		const struct vif_device *vif = v;
2489		const char *name =  vif->dev ? vif->dev->name : "none";
2490
2491		seq_printf(seq,
2492			   "%2Zd %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
2493			   vif - mrt->vif_table,
2494			   name, vif->bytes_in, vif->pkt_in,
2495			   vif->bytes_out, vif->pkt_out,
2496			   vif->flags, vif->local, vif->remote);
2497	}
2498	return 0;
2499}
2500
2501static const struct seq_operations ipmr_vif_seq_ops = {
2502	.start = ipmr_vif_seq_start,
2503	.next  = ipmr_vif_seq_next,
2504	.stop  = ipmr_vif_seq_stop,
2505	.show  = ipmr_vif_seq_show,
2506};
2507
2508static int ipmr_vif_open(struct inode *inode, struct file *file)
2509{
2510	return seq_open_net(inode, file, &ipmr_vif_seq_ops,
2511			    sizeof(struct ipmr_vif_iter));
2512}
2513
2514static const struct file_operations ipmr_vif_fops = {
2515	.owner	 = THIS_MODULE,
2516	.open    = ipmr_vif_open,
2517	.read    = seq_read,
2518	.llseek  = seq_lseek,
2519	.release = seq_release_net,
2520};
2521
2522struct ipmr_mfc_iter {
2523	struct seq_net_private p;
2524	struct mr_table *mrt;
2525	struct list_head *cache;
2526	int ct;
2527};
2528
2529
2530static struct mfc_cache *ipmr_mfc_seq_idx(struct net *net,
2531					  struct ipmr_mfc_iter *it, loff_t pos)
2532{
2533	struct mr_table *mrt = it->mrt;
2534	struct mfc_cache *mfc;
2535
2536	rcu_read_lock();
2537	for (it->ct = 0; it->ct < MFC_LINES; it->ct++) {
2538		it->cache = &mrt->mfc_cache_array[it->ct];
2539		list_for_each_entry_rcu(mfc, it->cache, list)
2540			if (pos-- == 0)
2541				return mfc;
2542	}
2543	rcu_read_unlock();
2544
2545	spin_lock_bh(&mfc_unres_lock);
2546	it->cache = &mrt->mfc_unres_queue;
2547	list_for_each_entry(mfc, it->cache, list)
2548		if (pos-- == 0)
2549			return mfc;
2550	spin_unlock_bh(&mfc_unres_lock);
2551
2552	it->cache = NULL;
2553	return NULL;
2554}
2555
2556
2557static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2558{
2559	struct ipmr_mfc_iter *it = seq->private;
2560	struct net *net = seq_file_net(seq);
2561	struct mr_table *mrt;
2562
2563	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2564	if (mrt == NULL)
2565		return ERR_PTR(-ENOENT);
2566
2567	it->mrt = mrt;
2568	it->cache = NULL;
2569	it->ct = 0;
2570	return *pos ? ipmr_mfc_seq_idx(net, seq->private, *pos - 1)
2571		: SEQ_START_TOKEN;
2572}
2573
2574static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2575{
2576	struct mfc_cache *mfc = v;
2577	struct ipmr_mfc_iter *it = seq->private;
2578	struct net *net = seq_file_net(seq);
2579	struct mr_table *mrt = it->mrt;
2580
2581	++*pos;
2582
2583	if (v == SEQ_START_TOKEN)
2584		return ipmr_mfc_seq_idx(net, seq->private, 0);
2585
2586	if (mfc->list.next != it->cache)
2587		return list_entry(mfc->list.next, struct mfc_cache, list);
2588
2589	if (it->cache == &mrt->mfc_unres_queue)
2590		goto end_of_list;
2591
2592	BUG_ON(it->cache != &mrt->mfc_cache_array[it->ct]);
2593
2594	while (++it->ct < MFC_LINES) {
2595		it->cache = &mrt->mfc_cache_array[it->ct];
2596		if (list_empty(it->cache))
2597			continue;
2598		return list_first_entry(it->cache, struct mfc_cache, list);
2599	}
2600
2601	/* exhausted cache_array, show unresolved */
2602	rcu_read_unlock();
2603	it->cache = &mrt->mfc_unres_queue;
2604	it->ct = 0;
2605
2606	spin_lock_bh(&mfc_unres_lock);
2607	if (!list_empty(it->cache))
2608		return list_first_entry(it->cache, struct mfc_cache, list);
2609
2610end_of_list:
2611	spin_unlock_bh(&mfc_unres_lock);
2612	it->cache = NULL;
2613
2614	return NULL;
2615}
2616
2617static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
2618{
2619	struct ipmr_mfc_iter *it = seq->private;
2620	struct mr_table *mrt = it->mrt;
2621
2622	if (it->cache == &mrt->mfc_unres_queue)
2623		spin_unlock_bh(&mfc_unres_lock);
2624	else if (it->cache == &mrt->mfc_cache_array[it->ct])
2625		rcu_read_unlock();
2626}
2627
2628static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2629{
2630	int n;
2631
2632	if (v == SEQ_START_TOKEN) {
2633		seq_puts(seq,
2634		 "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
2635	} else {
2636		const struct mfc_cache *mfc = v;
2637		const struct ipmr_mfc_iter *it = seq->private;
2638		const struct mr_table *mrt = it->mrt;
2639
2640		seq_printf(seq, "%08X %08X %-3hd",
2641			   (__force u32) mfc->mfc_mcastgrp,
2642			   (__force u32) mfc->mfc_origin,
2643			   mfc->mfc_parent);
2644
2645		if (it->cache != &mrt->mfc_unres_queue) {
2646			seq_printf(seq, " %8lu %8lu %8lu",
2647				   mfc->mfc_un.res.pkt,
2648				   mfc->mfc_un.res.bytes,
2649				   mfc->mfc_un.res.wrong_if);
2650			for (n = mfc->mfc_un.res.minvif;
2651			     n < mfc->mfc_un.res.maxvif; n++) {
2652				if (VIF_EXISTS(mrt, n) &&
2653				    mfc->mfc_un.res.ttls[n] < 255)
2654					seq_printf(seq,
2655					   " %2d:%-3d",
2656					   n, mfc->mfc_un.res.ttls[n]);
2657			}
2658		} else {
2659			/* unresolved mfc_caches don't contain
2660			 * pkt, bytes and wrong_if values
2661			 */
2662			seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
2663		}
2664		seq_putc(seq, '\n');
2665	}
2666	return 0;
2667}
2668
2669static const struct seq_operations ipmr_mfc_seq_ops = {
2670	.start = ipmr_mfc_seq_start,
2671	.next  = ipmr_mfc_seq_next,
2672	.stop  = ipmr_mfc_seq_stop,
2673	.show  = ipmr_mfc_seq_show,
2674};
2675
2676static int ipmr_mfc_open(struct inode *inode, struct file *file)
2677{
2678	return seq_open_net(inode, file, &ipmr_mfc_seq_ops,
2679			    sizeof(struct ipmr_mfc_iter));
2680}
2681
2682static const struct file_operations ipmr_mfc_fops = {
2683	.owner	 = THIS_MODULE,
2684	.open    = ipmr_mfc_open,
2685	.read    = seq_read,
2686	.llseek  = seq_lseek,
2687	.release = seq_release_net,
2688};
2689#endif
2690
2691#ifdef CONFIG_IP_PIMSM_V2
2692static const struct net_protocol pim_protocol = {
2693	.handler	=	pim_rcv,
2694	.netns_ok	=	1,
2695};
2696#endif
2697
2698
2699/*
2700 *	Setup for IP multicast routing
2701 */
2702static int __net_init ipmr_net_init(struct net *net)
2703{
2704	int err;
2705
2706	err = ipmr_rules_init(net);
2707	if (err < 0)
2708		goto fail;
2709
2710#ifdef CONFIG_PROC_FS
2711	err = -ENOMEM;
2712	if (!proc_create("ip_mr_vif", 0, net->proc_net, &ipmr_vif_fops))
2713		goto proc_vif_fail;
2714	if (!proc_create("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_fops))
2715		goto proc_cache_fail;
2716#endif
2717	return 0;
2718
2719#ifdef CONFIG_PROC_FS
2720proc_cache_fail:
2721	remove_proc_entry("ip_mr_vif", net->proc_net);
2722proc_vif_fail:
2723	ipmr_rules_exit(net);
2724#endif
2725fail:
2726	return err;
2727}
2728
2729static void __net_exit ipmr_net_exit(struct net *net)
2730{
2731#ifdef CONFIG_PROC_FS
2732	remove_proc_entry("ip_mr_cache", net->proc_net);
2733	remove_proc_entry("ip_mr_vif", net->proc_net);
2734#endif
2735	ipmr_rules_exit(net);
2736}
2737
2738static struct pernet_operations ipmr_net_ops = {
2739	.init = ipmr_net_init,
2740	.exit = ipmr_net_exit,
2741};
2742
2743int __init ip_mr_init(void)
2744{
2745	int err;
2746
2747	mrt_cachep = kmem_cache_create("ip_mrt_cache",
2748				       sizeof(struct mfc_cache),
2749				       0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
2750				       NULL);
2751	if (!mrt_cachep)
2752		return -ENOMEM;
2753
2754	err = register_pernet_subsys(&ipmr_net_ops);
2755	if (err)
2756		goto reg_pernet_fail;
2757
2758	err = register_netdevice_notifier(&ip_mr_notifier);
2759	if (err)
2760		goto reg_notif_fail;
2761#ifdef CONFIG_IP_PIMSM_V2
2762	if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
2763		pr_err("%s: can't add PIM protocol\n", __func__);
2764		err = -EAGAIN;
2765		goto add_proto_fail;
2766	}
2767#endif
2768	rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
2769		      NULL, ipmr_rtm_dumproute, NULL);
2770	return 0;
2771
2772#ifdef CONFIG_IP_PIMSM_V2
2773add_proto_fail:
2774	unregister_netdevice_notifier(&ip_mr_notifier);
2775#endif
2776reg_notif_fail:
2777	unregister_pernet_subsys(&ipmr_net_ops);
2778reg_pernet_fail:
2779	kmem_cache_destroy(mrt_cachep);
2780	return err;
2781}
2782