2 * IP multicast routing support for mrouted 3.6/3.8
4 * (c) 1995 Alan Cox, <alan@lxorguk.ukuu.org.uk>
5 * Linux Consultancy and Custom Driver Development
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.
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
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.
29 #include <asm/system.h>
30 #include <asm/uaccess.h>
31 #include <linux/types.h>
32 #include <linux/capability.h>
33 #include <linux/errno.h>
34 #include <linux/timer.h>
36 #include <linux/kernel.h>
37 #include <linux/fcntl.h>
38 #include <linux/stat.h>
39 #include <linux/socket.h>
41 #include <linux/inet.h>
42 #include <linux/netdevice.h>
43 #include <linux/inetdevice.h>
44 #include <linux/igmp.h>
45 #include <linux/proc_fs.h>
46 #include <linux/seq_file.h>
47 #include <linux/mroute.h>
48 #include <linux/init.h>
49 #include <linux/if_ether.h>
50 #include <linux/slab.h>
51 #include <net/net_namespace.h>
53 #include <net/protocol.h>
54 #include <linux/skbuff.h>
55 #include <net/route.h>
60 #include <linux/notifier.h>
61 #include <linux/if_arp.h>
62 #include <linux/netfilter_ipv4.h>
63 #include <linux/compat.h>
64 #include <linux/export.h>
66 #include <net/checksum.h>
67 #include <net/netlink.h>
68 #include <net/fib_rules.h>
70 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
71 #define CONFIG_IP_PIMSM 1
75 struct list_head list;
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];
86 atomic_t cache_resolve_queue_len;
89 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
90 int mroute_reg_vif_num;
95 struct fib_rule common;
102 /* Big lock, protecting vif table, mrt cache and mroute socket state.
103 * Note that the changes are semaphored via rtnl_lock.
106 static DEFINE_RWLOCK(mrt_lock);
109 * Multicast router control variables
112 #define VIF_EXISTS(_mrt, _idx) ((_mrt)->vif_table[_idx].dev != NULL)
114 /* Special spinlock for queue of unresolved entries */
115 static DEFINE_SPINLOCK(mfc_unres_lock);
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.
122 * In this case data path is free of exclusive locks at all.
125 static struct kmem_cache *mrt_cachep __read_mostly;
127 static struct mr_table *ipmr_new_table(struct net *net, u32 id);
128 static void ipmr_free_table(struct mr_table *mrt);
130 static int ip_mr_forward(struct net *net, struct mr_table *mrt,
131 struct sk_buff *skb, struct mfc_cache *cache,
133 static int ipmr_cache_report(struct mr_table *mrt,
134 struct sk_buff *pkt, vifi_t vifi, int assert);
135 static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
136 struct mfc_cache *c, struct rtmsg *rtm);
137 static void mroute_clean_tables(struct mr_table *mrt, bool all);
138 static void ipmr_expire_process(unsigned long arg);
140 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
141 #define ipmr_for_each_table(mrt, net) \
142 list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list)
144 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
146 struct mr_table *mrt;
148 ipmr_for_each_table(mrt, net) {
155 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
156 struct mr_table **mrt)
159 struct ipmr_result res;
160 struct fib_lookup_arg arg = {
162 .flags = FIB_LOOKUP_NOREF,
165 err = fib_rules_lookup(net->ipv4.mr_rules_ops,
166 flowi4_to_flowi(flp4), 0, &arg);
173 static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
174 int flags, struct fib_lookup_arg *arg)
176 struct ipmr_result *res = arg->result;
177 struct mr_table *mrt;
179 switch (rule->action) {
182 case FR_ACT_UNREACHABLE:
184 case FR_ACT_PROHIBIT:
186 case FR_ACT_BLACKHOLE:
191 mrt = ipmr_get_table(rule->fr_net, rule->table);
198 static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
203 static const struct nla_policy ipmr_rule_policy[FRA_MAX + 1] = {
207 static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
208 struct fib_rule_hdr *frh, struct nlattr **tb)
213 static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
219 static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
220 struct fib_rule_hdr *frh)
228 static const struct fib_rules_ops __net_initdata ipmr_rules_ops_template = {
229 .family = RTNL_FAMILY_IPMR,
230 .rule_size = sizeof(struct ipmr_rule),
231 .addr_size = sizeof(u32),
232 .action = ipmr_rule_action,
233 .match = ipmr_rule_match,
234 .configure = ipmr_rule_configure,
235 .compare = ipmr_rule_compare,
236 .default_pref = fib_default_rule_pref,
237 .fill = ipmr_rule_fill,
238 .nlgroup = RTNLGRP_IPV4_RULE,
239 .policy = ipmr_rule_policy,
240 .owner = THIS_MODULE,
243 static int __net_init ipmr_rules_init(struct net *net)
245 struct fib_rules_ops *ops;
246 struct mr_table *mrt;
249 ops = fib_rules_register(&ipmr_rules_ops_template, net);
253 INIT_LIST_HEAD(&net->ipv4.mr_tables);
255 mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
261 err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
265 net->ipv4.mr_rules_ops = ops;
271 fib_rules_unregister(ops);
275 static void __net_exit ipmr_rules_exit(struct net *net)
277 struct mr_table *mrt, *next;
279 list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
280 list_del(&mrt->list);
281 ipmr_free_table(mrt);
283 fib_rules_unregister(net->ipv4.mr_rules_ops);
286 #define ipmr_for_each_table(mrt, net) \
287 for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
289 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
291 return net->ipv4.mrt;
294 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
295 struct mr_table **mrt)
297 *mrt = net->ipv4.mrt;
301 static int __net_init ipmr_rules_init(struct net *net)
303 net->ipv4.mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
304 return net->ipv4.mrt ? 0 : -ENOMEM;
307 static void __net_exit ipmr_rules_exit(struct net *net)
309 ipmr_free_table(net->ipv4.mrt);
313 static struct mr_table *ipmr_new_table(struct net *net, u32 id)
315 struct mr_table *mrt;
318 mrt = ipmr_get_table(net, id);
322 mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
325 write_pnet(&mrt->net, net);
328 /* Forwarding cache */
329 for (i = 0; i < MFC_LINES; i++)
330 INIT_LIST_HEAD(&mrt->mfc_cache_array[i]);
332 INIT_LIST_HEAD(&mrt->mfc_unres_queue);
334 setup_timer(&mrt->ipmr_expire_timer, ipmr_expire_process,
337 #ifdef CONFIG_IP_PIMSM
338 mrt->mroute_reg_vif_num = -1;
340 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
341 list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
346 static void ipmr_free_table(struct mr_table *mrt)
348 del_timer_sync(&mrt->ipmr_expire_timer);
349 mroute_clean_tables(mrt, true);
353 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
355 static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
357 struct net *net = dev_net(dev);
361 dev = __dev_get_by_name(net, "tunl0");
363 const struct net_device_ops *ops = dev->netdev_ops;
365 struct ip_tunnel_parm p;
367 memset(&p, 0, sizeof(p));
368 p.iph.daddr = v->vifc_rmt_addr.s_addr;
369 p.iph.saddr = v->vifc_lcl_addr.s_addr;
372 p.iph.protocol = IPPROTO_IPIP;
373 sprintf(p.name, "dvmrp%d", v->vifc_vifi);
374 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
376 if (ops->ndo_do_ioctl) {
377 mm_segment_t oldfs = get_fs();
380 ops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
387 struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
389 struct net_device *dev;
391 dev = __dev_get_by_name(net, "tunl0");
394 const struct net_device_ops *ops = dev->netdev_ops;
397 struct ip_tunnel_parm p;
398 struct in_device *in_dev;
400 memset(&p, 0, sizeof(p));
401 p.iph.daddr = v->vifc_rmt_addr.s_addr;
402 p.iph.saddr = v->vifc_lcl_addr.s_addr;
405 p.iph.protocol = IPPROTO_IPIP;
406 sprintf(p.name, "dvmrp%d", v->vifc_vifi);
407 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
409 if (ops->ndo_do_ioctl) {
410 mm_segment_t oldfs = get_fs();
413 err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
421 (dev = __dev_get_by_name(net, p.name)) != NULL) {
422 dev->flags |= IFF_MULTICAST;
424 in_dev = __in_dev_get_rtnl(dev);
428 ipv4_devconf_setall(in_dev);
429 IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
439 /* allow the register to be completed before unregistering. */
443 unregister_netdevice(dev);
447 #ifdef CONFIG_IP_PIMSM
449 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
451 struct net *net = dev_net(dev);
452 struct mr_table *mrt;
453 struct flowi4 fl4 = {
454 .flowi4_oif = dev->ifindex,
455 .flowi4_iif = skb->skb_iif,
456 .flowi4_mark = skb->mark,
460 err = ipmr_fib_lookup(net, &fl4, &mrt);
466 read_lock(&mrt_lock);
467 dev->stats.tx_bytes += skb->len;
468 dev->stats.tx_packets++;
469 ipmr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, IGMPMSG_WHOLEPKT);
470 read_unlock(&mrt_lock);
475 static const struct net_device_ops reg_vif_netdev_ops = {
476 .ndo_start_xmit = reg_vif_xmit,
479 static void reg_vif_setup(struct net_device *dev)
481 dev->type = ARPHRD_PIMREG;
482 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 8;
483 dev->flags = IFF_NOARP;
484 dev->netdev_ops = ®_vif_netdev_ops,
485 dev->destructor = free_netdev;
486 dev->features |= NETIF_F_NETNS_LOCAL;
489 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
491 struct net_device *dev;
492 struct in_device *in_dev;
495 if (mrt->id == RT_TABLE_DEFAULT)
496 sprintf(name, "pimreg");
498 sprintf(name, "pimreg%u", mrt->id);
500 dev = alloc_netdev(0, name, reg_vif_setup);
505 dev_net_set(dev, net);
507 if (register_netdevice(dev)) {
514 in_dev = __in_dev_get_rcu(dev);
520 ipv4_devconf_setall(in_dev);
521 IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
532 /* allow the register to be completed before unregistering. */
536 unregister_netdevice(dev);
543 * @notify: Set to 1, if the caller is a notifier_call
546 static int vif_delete(struct mr_table *mrt, int vifi, int notify,
547 struct list_head *head)
549 struct vif_device *v;
550 struct net_device *dev;
551 struct in_device *in_dev;
553 if (vifi < 0 || vifi >= mrt->maxvif)
554 return -EADDRNOTAVAIL;
556 v = &mrt->vif_table[vifi];
558 write_lock_bh(&mrt_lock);
563 write_unlock_bh(&mrt_lock);
564 return -EADDRNOTAVAIL;
567 #ifdef CONFIG_IP_PIMSM
568 if (vifi == mrt->mroute_reg_vif_num)
569 mrt->mroute_reg_vif_num = -1;
572 if (vifi + 1 == mrt->maxvif) {
575 for (tmp = vifi - 1; tmp >= 0; tmp--) {
576 if (VIF_EXISTS(mrt, tmp))
582 write_unlock_bh(&mrt_lock);
584 dev_set_allmulti(dev, -1);
586 in_dev = __in_dev_get_rtnl(dev);
588 IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
589 ip_rt_multicast_event(in_dev);
592 if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
593 unregister_netdevice_queue(dev, head);
599 static void ipmr_cache_free_rcu(struct rcu_head *head)
601 struct mfc_cache *c = container_of(head, struct mfc_cache, rcu);
603 kmem_cache_free(mrt_cachep, c);
606 static inline void ipmr_cache_free(struct mfc_cache *c)
608 call_rcu(&c->rcu, ipmr_cache_free_rcu);
611 /* Destroy an unresolved cache entry, killing queued skbs
612 * and reporting error to netlink readers.
615 static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
617 struct net *net = read_pnet(&mrt->net);
621 atomic_dec(&mrt->cache_resolve_queue_len);
623 while ((skb = skb_dequeue(&c->mfc_un.unres.unresolved))) {
624 if (ip_hdr(skb)->version == 0) {
625 struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
626 nlh->nlmsg_type = NLMSG_ERROR;
627 nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
628 skb_trim(skb, nlh->nlmsg_len);
630 e->error = -ETIMEDOUT;
631 memset(&e->msg, 0, sizeof(e->msg));
633 rtnl_unicast(skb, net, NETLINK_CB(skb).pid);
643 /* Timer process for the unresolved queue. */
645 static void ipmr_expire_process(unsigned long arg)
647 struct mr_table *mrt = (struct mr_table *)arg;
649 unsigned long expires;
650 struct mfc_cache *c, *next;
652 if (!spin_trylock(&mfc_unres_lock)) {
653 mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10);
657 if (list_empty(&mrt->mfc_unres_queue))
663 list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
664 if (time_after(c->mfc_un.unres.expires, now)) {
665 unsigned long interval = c->mfc_un.unres.expires - now;
666 if (interval < expires)
672 ipmr_destroy_unres(mrt, c);
675 if (!list_empty(&mrt->mfc_unres_queue))
676 mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
679 spin_unlock(&mfc_unres_lock);
682 /* Fill oifs list. It is called under write locked mrt_lock. */
684 static void ipmr_update_thresholds(struct mr_table *mrt, struct mfc_cache *cache,
689 cache->mfc_un.res.minvif = MAXVIFS;
690 cache->mfc_un.res.maxvif = 0;
691 memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
693 for (vifi = 0; vifi < mrt->maxvif; vifi++) {
694 if (VIF_EXISTS(mrt, vifi) &&
695 ttls[vifi] && ttls[vifi] < 255) {
696 cache->mfc_un.res.ttls[vifi] = ttls[vifi];
697 if (cache->mfc_un.res.minvif > vifi)
698 cache->mfc_un.res.minvif = vifi;
699 if (cache->mfc_un.res.maxvif <= vifi)
700 cache->mfc_un.res.maxvif = vifi + 1;
705 static int vif_add(struct net *net, struct mr_table *mrt,
706 struct vifctl *vifc, int mrtsock)
708 int vifi = vifc->vifc_vifi;
709 struct vif_device *v = &mrt->vif_table[vifi];
710 struct net_device *dev;
711 struct in_device *in_dev;
715 if (VIF_EXISTS(mrt, vifi))
718 switch (vifc->vifc_flags) {
719 #ifdef CONFIG_IP_PIMSM
722 * Special Purpose VIF in PIM
723 * All the packets will be sent to the daemon
725 if (mrt->mroute_reg_vif_num >= 0)
727 dev = ipmr_reg_vif(net, mrt);
730 err = dev_set_allmulti(dev, 1);
732 unregister_netdevice(dev);
739 dev = ipmr_new_tunnel(net, vifc);
742 err = dev_set_allmulti(dev, 1);
744 ipmr_del_tunnel(dev, vifc);
750 case VIFF_USE_IFINDEX:
752 if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
753 dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
754 if (dev && __in_dev_get_rtnl(dev) == NULL) {
756 return -EADDRNOTAVAIL;
759 dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
762 return -EADDRNOTAVAIL;
763 err = dev_set_allmulti(dev, 1);
773 in_dev = __in_dev_get_rtnl(dev);
776 return -EADDRNOTAVAIL;
778 IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
779 ip_rt_multicast_event(in_dev);
781 /* Fill in the VIF structures */
783 v->rate_limit = vifc->vifc_rate_limit;
784 v->local = vifc->vifc_lcl_addr.s_addr;
785 v->remote = vifc->vifc_rmt_addr.s_addr;
786 v->flags = vifc->vifc_flags;
788 v->flags |= VIFF_STATIC;
789 v->threshold = vifc->vifc_threshold;
794 v->link = dev->ifindex;
795 if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER))
796 v->link = dev->iflink;
798 /* And finish update writing critical data */
799 write_lock_bh(&mrt_lock);
801 #ifdef CONFIG_IP_PIMSM
802 if (v->flags & VIFF_REGISTER)
803 mrt->mroute_reg_vif_num = vifi;
805 if (vifi+1 > mrt->maxvif)
806 mrt->maxvif = vifi+1;
807 write_unlock_bh(&mrt_lock);
811 /* called with rcu_read_lock() */
812 static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
816 int line = MFC_HASH(mcastgrp, origin);
819 list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list) {
820 if (c->mfc_origin == origin && c->mfc_mcastgrp == mcastgrp)
827 * Allocate a multicast cache entry
829 static struct mfc_cache *ipmr_cache_alloc(void)
831 struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
834 c->mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
835 c->mfc_un.res.minvif = MAXVIFS;
840 static struct mfc_cache *ipmr_cache_alloc_unres(void)
842 struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
845 skb_queue_head_init(&c->mfc_un.unres.unresolved);
846 c->mfc_un.unres.expires = jiffies + 10*HZ;
852 * A cache entry has gone into a resolved state from queued
855 static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
856 struct mfc_cache *uc, struct mfc_cache *c)
861 /* Play the pending entries through our router */
863 while ((skb = __skb_dequeue(&uc->mfc_un.unres.unresolved))) {
864 if (ip_hdr(skb)->version == 0) {
865 struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
867 if (__ipmr_fill_mroute(mrt, skb, c, NLMSG_DATA(nlh)) > 0) {
868 nlh->nlmsg_len = skb_tail_pointer(skb) -
871 nlh->nlmsg_type = NLMSG_ERROR;
872 nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
873 skb_trim(skb, nlh->nlmsg_len);
875 e->error = -EMSGSIZE;
876 memset(&e->msg, 0, sizeof(e->msg));
879 rtnl_unicast(skb, net, NETLINK_CB(skb).pid);
881 ip_mr_forward(net, mrt, skb, c, 0);
887 * Bounce a cache query up to mrouted. We could use netlink for this but mrouted
888 * expects the following bizarre scheme.
890 * Called under mrt_lock.
893 static int ipmr_cache_report(struct mr_table *mrt,
894 struct sk_buff *pkt, vifi_t vifi, int assert)
897 const int ihl = ip_hdrlen(pkt);
898 struct igmphdr *igmp;
900 struct sock *mroute_sk;
903 #ifdef CONFIG_IP_PIMSM
904 if (assert == IGMPMSG_WHOLEPKT)
905 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
908 skb = alloc_skb(128, GFP_ATOMIC);
913 #ifdef CONFIG_IP_PIMSM
914 if (assert == IGMPMSG_WHOLEPKT) {
915 /* Ugly, but we have no choice with this interface.
916 * Duplicate old header, fix ihl, length etc.
917 * And all this only to mangle msg->im_msgtype and
918 * to set msg->im_mbz to "mbz" :-)
920 skb_push(skb, sizeof(struct iphdr));
921 skb_reset_network_header(skb);
922 skb_reset_transport_header(skb);
923 msg = (struct igmpmsg *)skb_network_header(skb);
924 memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
925 msg->im_msgtype = IGMPMSG_WHOLEPKT;
927 msg->im_vif = mrt->mroute_reg_vif_num;
928 ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
929 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
930 sizeof(struct iphdr));
935 /* Copy the IP header */
937 skb->network_header = skb->tail;
939 skb_copy_to_linear_data(skb, pkt->data, ihl);
940 ip_hdr(skb)->protocol = 0; /* Flag to the kernel this is a route add */
941 msg = (struct igmpmsg *)skb_network_header(skb);
943 skb_dst_set(skb, dst_clone(skb_dst(pkt)));
947 igmp = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
949 msg->im_msgtype = assert;
951 ip_hdr(skb)->tot_len = htons(skb->len); /* Fix the length */
952 skb->transport_header = skb->network_header;
956 mroute_sk = rcu_dereference(mrt->mroute_sk);
957 if (mroute_sk == NULL) {
963 /* Deliver to mrouted */
965 ret = sock_queue_rcv_skb(mroute_sk, skb);
969 printk(KERN_WARNING "mroute: pending queue full, dropping entries.\n");
977 * Queue a packet for resolution. It gets locked cache entry!
981 ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi, struct sk_buff *skb)
986 const struct iphdr *iph = ip_hdr(skb);
988 spin_lock_bh(&mfc_unres_lock);
989 list_for_each_entry(c, &mrt->mfc_unres_queue, list) {
990 if (c->mfc_mcastgrp == iph->daddr &&
991 c->mfc_origin == iph->saddr) {
998 /* Create a new entry if allowable */
1000 if (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
1001 (c = ipmr_cache_alloc_unres()) == NULL) {
1002 spin_unlock_bh(&mfc_unres_lock);
1008 /* Fill in the new cache entry */
1011 c->mfc_origin = iph->saddr;
1012 c->mfc_mcastgrp = iph->daddr;
1014 /* Reflect first query at mrouted. */
1016 err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1018 /* If the report failed throw the cache entry
1021 spin_unlock_bh(&mfc_unres_lock);
1028 atomic_inc(&mrt->cache_resolve_queue_len);
1029 list_add(&c->list, &mrt->mfc_unres_queue);
1031 if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1032 mod_timer(&mrt->ipmr_expire_timer, c->mfc_un.unres.expires);
1035 /* See if we can append the packet */
1037 if (c->mfc_un.unres.unresolved.qlen > 3) {
1041 skb_queue_tail(&c->mfc_un.unres.unresolved, skb);
1045 spin_unlock_bh(&mfc_unres_lock);
1050 * MFC cache manipulation by user space mroute daemon
1053 static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc)
1056 struct mfc_cache *c, *next;
1058 line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1060 list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[line], list) {
1061 if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1062 c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) {
1063 list_del_rcu(&c->list);
1072 static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1073 struct mfcctl *mfc, int mrtsock)
1077 struct mfc_cache *uc, *c;
1079 if (mfc->mfcc_parent >= MAXVIFS)
1082 line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1084 list_for_each_entry(c, &mrt->mfc_cache_array[line], list) {
1085 if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1086 c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) {
1093 write_lock_bh(&mrt_lock);
1094 c->mfc_parent = mfc->mfcc_parent;
1095 ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1097 c->mfc_flags |= MFC_STATIC;
1098 write_unlock_bh(&mrt_lock);
1102 if (!ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1105 c = ipmr_cache_alloc();
1109 c->mfc_origin = mfc->mfcc_origin.s_addr;
1110 c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1111 c->mfc_parent = mfc->mfcc_parent;
1112 ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1114 c->mfc_flags |= MFC_STATIC;
1116 list_add_rcu(&c->list, &mrt->mfc_cache_array[line]);
1119 * Check to see if we resolved a queued list. If so we
1120 * need to send on the frames and tidy up.
1123 spin_lock_bh(&mfc_unres_lock);
1124 list_for_each_entry(uc, &mrt->mfc_unres_queue, list) {
1125 if (uc->mfc_origin == c->mfc_origin &&
1126 uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1127 list_del(&uc->list);
1128 atomic_dec(&mrt->cache_resolve_queue_len);
1133 if (list_empty(&mrt->mfc_unres_queue))
1134 del_timer(&mrt->ipmr_expire_timer);
1135 spin_unlock_bh(&mfc_unres_lock);
1138 ipmr_cache_resolve(net, mrt, uc, c);
1139 ipmr_cache_free(uc);
1145 * Close the multicast socket, and clear the vif tables etc
1148 static void mroute_clean_tables(struct mr_table *mrt, bool all)
1152 struct mfc_cache *c, *next;
1154 /* Shut down all active vif entries */
1156 for (i = 0; i < mrt->maxvif; i++) {
1157 if (!all && (mrt->vif_table[i].flags & VIFF_STATIC))
1159 vif_delete(mrt, i, 0, &list);
1161 unregister_netdevice_many(&list);
1163 /* Wipe the cache */
1165 for (i = 0; i < MFC_LINES; i++) {
1166 list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[i], list) {
1167 if (!all && (c->mfc_flags & MFC_STATIC))
1169 list_del_rcu(&c->list);
1174 if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1175 spin_lock_bh(&mfc_unres_lock);
1176 list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
1178 ipmr_destroy_unres(mrt, c);
1180 spin_unlock_bh(&mfc_unres_lock);
1184 /* called from ip_ra_control(), before an RCU grace period,
1185 * we dont need to call synchronize_rcu() here
1187 static void mrtsock_destruct(struct sock *sk)
1189 struct net *net = sock_net(sk);
1190 struct mr_table *mrt;
1193 ipmr_for_each_table(mrt, net) {
1194 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1195 IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1196 RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1197 mroute_clean_tables(mrt, false);
1204 * Socket options and virtual interface manipulation. The whole
1205 * virtual interface system is a complete heap, but unfortunately
1206 * that's how BSD mrouted happens to think. Maybe one day with a proper
1207 * MOSPF/PIM router set up we can clean this up.
1210 int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsigned int optlen)
1215 struct net *net = sock_net(sk);
1216 struct mr_table *mrt;
1218 mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1222 if (optname != MRT_INIT) {
1223 if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1224 !capable(CAP_NET_ADMIN))
1230 if (sk->sk_type != SOCK_RAW ||
1231 inet_sk(sk)->inet_num != IPPROTO_IGMP)
1233 if (optlen != sizeof(int))
1234 return -ENOPROTOOPT;
1237 if (rtnl_dereference(mrt->mroute_sk)) {
1242 ret = ip_ra_control(sk, 1, mrtsock_destruct);
1244 rcu_assign_pointer(mrt->mroute_sk, sk);
1245 IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1250 if (sk != rcu_access_pointer(mrt->mroute_sk))
1252 return ip_ra_control(sk, 0, NULL);
1255 if (optlen != sizeof(vif))
1257 if (copy_from_user(&vif, optval, sizeof(vif)))
1259 if (vif.vifc_vifi >= MAXVIFS)
1262 if (optname == MRT_ADD_VIF) {
1263 ret = vif_add(net, mrt, &vif,
1264 sk == rtnl_dereference(mrt->mroute_sk));
1266 ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1272 * Manipulate the forwarding caches. These live
1273 * in a sort of kernel/user symbiosis.
1277 if (optlen != sizeof(mfc))
1279 if (copy_from_user(&mfc, optval, sizeof(mfc)))
1282 if (optname == MRT_DEL_MFC)
1283 ret = ipmr_mfc_delete(mrt, &mfc);
1285 ret = ipmr_mfc_add(net, mrt, &mfc,
1286 sk == rtnl_dereference(mrt->mroute_sk));
1290 * Control PIM assert.
1295 if (get_user(v, (int __user *)optval))
1297 mrt->mroute_do_assert = (v) ? 1 : 0;
1300 #ifdef CONFIG_IP_PIMSM
1305 if (get_user(v, (int __user *)optval))
1311 if (v != mrt->mroute_do_pim) {
1312 mrt->mroute_do_pim = v;
1313 mrt->mroute_do_assert = v;
1319 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
1324 if (optlen != sizeof(u32))
1326 if (get_user(v, (u32 __user *)optval))
1331 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1334 if (!ipmr_new_table(net, v))
1336 raw_sk(sk)->ipmr_table = v;
1343 * Spurious command, or MRT_VERSION which you cannot
1347 return -ENOPROTOOPT;
1352 * Getsock opt support for the multicast routing system.
1355 int ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen)
1359 struct net *net = sock_net(sk);
1360 struct mr_table *mrt;
1362 mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1366 if (optname != MRT_VERSION &&
1367 #ifdef CONFIG_IP_PIMSM
1368 optname != MRT_PIM &&
1370 optname != MRT_ASSERT)
1371 return -ENOPROTOOPT;
1373 if (get_user(olr, optlen))
1376 olr = min_t(unsigned int, olr, sizeof(int));
1380 if (put_user(olr, optlen))
1382 if (optname == MRT_VERSION)
1384 #ifdef CONFIG_IP_PIMSM
1385 else if (optname == MRT_PIM)
1386 val = mrt->mroute_do_pim;
1389 val = mrt->mroute_do_assert;
1390 if (copy_to_user(optval, &val, olr))
1396 * The IP multicast ioctl support routines.
1399 int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
1401 struct sioc_sg_req sr;
1402 struct sioc_vif_req vr;
1403 struct vif_device *vif;
1404 struct mfc_cache *c;
1405 struct net *net = sock_net(sk);
1406 struct mr_table *mrt;
1408 mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1414 if (copy_from_user(&vr, arg, sizeof(vr)))
1416 if (vr.vifi >= mrt->maxvif)
1418 read_lock(&mrt_lock);
1419 vif = &mrt->vif_table[vr.vifi];
1420 if (VIF_EXISTS(mrt, vr.vifi)) {
1421 vr.icount = vif->pkt_in;
1422 vr.ocount = vif->pkt_out;
1423 vr.ibytes = vif->bytes_in;
1424 vr.obytes = vif->bytes_out;
1425 read_unlock(&mrt_lock);
1427 if (copy_to_user(arg, &vr, sizeof(vr)))
1431 read_unlock(&mrt_lock);
1432 return -EADDRNOTAVAIL;
1434 if (copy_from_user(&sr, arg, sizeof(sr)))
1438 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1440 sr.pktcnt = c->mfc_un.res.pkt;
1441 sr.bytecnt = c->mfc_un.res.bytes;
1442 sr.wrong_if = c->mfc_un.res.wrong_if;
1445 if (copy_to_user(arg, &sr, sizeof(sr)))
1450 return -EADDRNOTAVAIL;
1452 return -ENOIOCTLCMD;
1456 #ifdef CONFIG_COMPAT
1457 struct compat_sioc_sg_req {
1460 compat_ulong_t pktcnt;
1461 compat_ulong_t bytecnt;
1462 compat_ulong_t wrong_if;
1465 struct compat_sioc_vif_req {
1466 vifi_t vifi; /* Which iface */
1467 compat_ulong_t icount;
1468 compat_ulong_t ocount;
1469 compat_ulong_t ibytes;
1470 compat_ulong_t obytes;
1473 int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1475 struct compat_sioc_sg_req sr;
1476 struct compat_sioc_vif_req vr;
1477 struct vif_device *vif;
1478 struct mfc_cache *c;
1479 struct net *net = sock_net(sk);
1480 struct mr_table *mrt;
1482 mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1488 if (copy_from_user(&vr, arg, sizeof(vr)))
1490 if (vr.vifi >= mrt->maxvif)
1492 read_lock(&mrt_lock);
1493 vif = &mrt->vif_table[vr.vifi];
1494 if (VIF_EXISTS(mrt, vr.vifi)) {
1495 vr.icount = vif->pkt_in;
1496 vr.ocount = vif->pkt_out;
1497 vr.ibytes = vif->bytes_in;
1498 vr.obytes = vif->bytes_out;
1499 read_unlock(&mrt_lock);
1501 if (copy_to_user(arg, &vr, sizeof(vr)))
1505 read_unlock(&mrt_lock);
1506 return -EADDRNOTAVAIL;
1508 if (copy_from_user(&sr, arg, sizeof(sr)))
1512 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1514 sr.pktcnt = c->mfc_un.res.pkt;
1515 sr.bytecnt = c->mfc_un.res.bytes;
1516 sr.wrong_if = c->mfc_un.res.wrong_if;
1519 if (copy_to_user(arg, &sr, sizeof(sr)))
1524 return -EADDRNOTAVAIL;
1526 return -ENOIOCTLCMD;
1532 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1534 struct net_device *dev = ptr;
1535 struct net *net = dev_net(dev);
1536 struct mr_table *mrt;
1537 struct vif_device *v;
1541 if (event != NETDEV_UNREGISTER)
1544 ipmr_for_each_table(mrt, net) {
1545 v = &mrt->vif_table[0];
1546 for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1548 vif_delete(mrt, ct, 1, &list);
1551 unregister_netdevice_many(&list);
1556 static struct notifier_block ip_mr_notifier = {
1557 .notifier_call = ipmr_device_event,
1561 * Encapsulate a packet by attaching a valid IPIP header to it.
1562 * This avoids tunnel drivers and other mess and gives us the speed so
1563 * important for multicast video.
1566 static void ip_encap(struct sk_buff *skb, __be32 saddr, __be32 daddr)
1569 const struct iphdr *old_iph = ip_hdr(skb);
1571 skb_push(skb, sizeof(struct iphdr));
1572 skb->transport_header = skb->network_header;
1573 skb_reset_network_header(skb);
1577 iph->tos = old_iph->tos;
1578 iph->ttl = old_iph->ttl;
1582 iph->protocol = IPPROTO_IPIP;
1584 iph->tot_len = htons(skb->len);
1585 ip_select_ident(skb, NULL);
1588 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1592 static inline int ipmr_forward_finish(struct sk_buff *skb)
1594 struct ip_options *opt = &(IPCB(skb)->opt);
1596 IP_INC_STATS(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTFORWDATAGRAMS);
1598 if (unlikely(opt->optlen))
1599 ip_forward_options(skb);
1601 return dst_output(skb);
1605 * Processing handlers for ipmr_forward
1608 static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1609 struct sk_buff *skb, struct mfc_cache *c, int vifi)
1611 const struct iphdr *iph = ip_hdr(skb);
1612 struct vif_device *vif = &mrt->vif_table[vifi];
1613 struct net_device *dev;
1618 if (vif->dev == NULL)
1621 #ifdef CONFIG_IP_PIMSM
1622 if (vif->flags & VIFF_REGISTER) {
1624 vif->bytes_out += skb->len;
1625 vif->dev->stats.tx_bytes += skb->len;
1626 vif->dev->stats.tx_packets++;
1627 ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1632 if (vif->flags & VIFF_TUNNEL) {
1633 rt = ip_route_output_ports(net, &fl4, NULL,
1634 vif->remote, vif->local,
1637 RT_TOS(iph->tos), vif->link);
1640 encap = sizeof(struct iphdr);
1642 rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1645 RT_TOS(iph->tos), vif->link);
1652 if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1653 /* Do not fragment multicasts. Alas, IPv4 does not
1654 * allow to send ICMP, so that packets will disappear
1658 IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS);
1663 encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1665 if (skb_cow(skb, encap)) {
1671 vif->bytes_out += skb->len;
1674 skb_dst_set(skb, &rt->dst);
1675 ip_decrease_ttl(ip_hdr(skb));
1677 /* FIXME: forward and output firewalls used to be called here.
1678 * What do we do with netfilter? -- RR
1680 if (vif->flags & VIFF_TUNNEL) {
1681 ip_encap(skb, vif->local, vif->remote);
1682 /* FIXME: extra output firewall step used to be here. --RR */
1683 vif->dev->stats.tx_packets++;
1684 vif->dev->stats.tx_bytes += skb->len;
1687 IPCB(skb)->flags |= IPSKB_FORWARDED;
1690 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1691 * not only before forwarding, but after forwarding on all output
1692 * interfaces. It is clear, if mrouter runs a multicasting
1693 * program, it should receive packets not depending to what interface
1694 * program is joined.
1695 * If we will not make it, the program will have to join on all
1696 * interfaces. On the other hand, multihoming host (or router, but
1697 * not mrouter) cannot join to more than one interface - it will
1698 * result in receiving multiple packets.
1700 NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD, skb, skb->dev, dev,
1701 ipmr_forward_finish);
1708 static int ipmr_find_vif(struct mr_table *mrt, struct net_device *dev)
1712 for (ct = mrt->maxvif-1; ct >= 0; ct--) {
1713 if (mrt->vif_table[ct].dev == dev)
1719 /* "local" means that we should preserve one skb (for local delivery) */
1721 static int ip_mr_forward(struct net *net, struct mr_table *mrt,
1722 struct sk_buff *skb, struct mfc_cache *cache,
1728 vif = cache->mfc_parent;
1729 cache->mfc_un.res.pkt++;
1730 cache->mfc_un.res.bytes += skb->len;
1733 * Wrong interface: drop packet and (maybe) send PIM assert.
1735 if (mrt->vif_table[vif].dev != skb->dev) {
1738 if (rt_is_output_route(skb_rtable(skb))) {
1739 /* It is our own packet, looped back.
1740 * Very complicated situation...
1742 * The best workaround until routing daemons will be
1743 * fixed is not to redistribute packet, if it was
1744 * send through wrong interface. It means, that
1745 * multicast applications WILL NOT work for
1746 * (S,G), which have default multicast route pointing
1747 * to wrong oif. In any case, it is not a good
1748 * idea to use multicasting applications on router.
1753 cache->mfc_un.res.wrong_if++;
1754 true_vifi = ipmr_find_vif(mrt, skb->dev);
1756 if (true_vifi >= 0 && mrt->mroute_do_assert &&
1757 /* pimsm uses asserts, when switching from RPT to SPT,
1758 * so that we cannot check that packet arrived on an oif.
1759 * It is bad, but otherwise we would need to move pretty
1760 * large chunk of pimd to kernel. Ough... --ANK
1762 (mrt->mroute_do_pim ||
1763 cache->mfc_un.res.ttls[true_vifi] < 255) &&
1765 cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) {
1766 cache->mfc_un.res.last_assert = jiffies;
1767 ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
1772 mrt->vif_table[vif].pkt_in++;
1773 mrt->vif_table[vif].bytes_in += skb->len;
1778 for (ct = cache->mfc_un.res.maxvif - 1;
1779 ct >= cache->mfc_un.res.minvif; ct--) {
1780 if (ip_hdr(skb)->ttl > cache->mfc_un.res.ttls[ct]) {
1782 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1785 ipmr_queue_xmit(net, mrt, skb2, cache,
1793 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1796 ipmr_queue_xmit(net, mrt, skb2, cache, psend);
1798 ipmr_queue_xmit(net, mrt, skb, cache, psend);
1809 static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
1811 struct rtable *rt = skb_rtable(skb);
1812 struct iphdr *iph = ip_hdr(skb);
1813 struct flowi4 fl4 = {
1814 .daddr = iph->daddr,
1815 .saddr = iph->saddr,
1816 .flowi4_tos = RT_TOS(iph->tos),
1817 .flowi4_oif = rt->rt_oif,
1818 .flowi4_iif = rt->rt_iif,
1819 .flowi4_mark = rt->rt_mark,
1821 struct mr_table *mrt;
1824 err = ipmr_fib_lookup(net, &fl4, &mrt);
1826 return ERR_PTR(err);
1831 * Multicast packets for forwarding arrive here
1832 * Called with rcu_read_lock();
1835 int ip_mr_input(struct sk_buff *skb)
1837 struct mfc_cache *cache;
1838 struct net *net = dev_net(skb->dev);
1839 int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
1840 struct mr_table *mrt;
1842 /* Packet is looped back after forward, it should not be
1843 * forwarded second time, but still can be delivered locally.
1845 if (IPCB(skb)->flags & IPSKB_FORWARDED)
1848 mrt = ipmr_rt_fib_lookup(net, skb);
1851 return PTR_ERR(mrt);
1854 if (IPCB(skb)->opt.router_alert) {
1855 if (ip_call_ra_chain(skb))
1857 } else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
1858 /* IGMPv1 (and broken IGMPv2 implementations sort of
1859 * Cisco IOS <= 11.2(8)) do not put router alert
1860 * option to IGMP packets destined to routable
1861 * groups. It is very bad, because it means
1862 * that we can forward NO IGMP messages.
1864 struct sock *mroute_sk;
1866 mroute_sk = rcu_dereference(mrt->mroute_sk);
1869 raw_rcv(mroute_sk, skb);
1875 /* already under rcu_read_lock() */
1876 cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
1879 * No usable cache entry
1881 if (cache == NULL) {
1885 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1886 ip_local_deliver(skb);
1892 read_lock(&mrt_lock);
1893 vif = ipmr_find_vif(mrt, skb->dev);
1895 int err2 = ipmr_cache_unresolved(mrt, vif, skb);
1896 read_unlock(&mrt_lock);
1900 read_unlock(&mrt_lock);
1905 read_lock(&mrt_lock);
1906 ip_mr_forward(net, mrt, skb, cache, local);
1907 read_unlock(&mrt_lock);
1910 return ip_local_deliver(skb);
1916 return ip_local_deliver(skb);
1921 #ifdef CONFIG_IP_PIMSM
1922 /* called with rcu_read_lock() */
1923 static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
1924 unsigned int pimlen)
1926 struct net_device *reg_dev = NULL;
1927 struct iphdr *encap;
1929 encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
1932 * a. packet is really sent to a multicast group
1933 * b. packet is not a NULL-REGISTER
1934 * c. packet is not truncated
1936 if (!ipv4_is_multicast(encap->daddr) ||
1937 encap->tot_len == 0 ||
1938 ntohs(encap->tot_len) + pimlen > skb->len)
1941 read_lock(&mrt_lock);
1942 if (mrt->mroute_reg_vif_num >= 0)
1943 reg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
1944 read_unlock(&mrt_lock);
1946 if (reg_dev == NULL)
1949 skb->mac_header = skb->network_header;
1950 skb_pull(skb, (u8 *)encap - skb->data);
1951 skb_reset_network_header(skb);
1952 skb->protocol = htons(ETH_P_IP);
1953 skb->ip_summed = CHECKSUM_NONE;
1954 skb->pkt_type = PACKET_HOST;
1956 skb_tunnel_rx(skb, reg_dev);
1960 return NET_RX_SUCCESS;
1964 #ifdef CONFIG_IP_PIMSM_V1
1966 * Handle IGMP messages of PIMv1
1969 int pim_rcv_v1(struct sk_buff *skb)
1971 struct igmphdr *pim;
1972 struct net *net = dev_net(skb->dev);
1973 struct mr_table *mrt;
1975 if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
1978 pim = igmp_hdr(skb);
1980 mrt = ipmr_rt_fib_lookup(net, skb);
1983 if (!mrt->mroute_do_pim ||
1984 pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
1987 if (__pim_rcv(mrt, skb, sizeof(*pim))) {
1995 #ifdef CONFIG_IP_PIMSM_V2
1996 static int pim_rcv(struct sk_buff *skb)
1998 struct pimreghdr *pim;
1999 struct net *net = dev_net(skb->dev);
2000 struct mr_table *mrt;
2002 if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2005 pim = (struct pimreghdr *)skb_transport_header(skb);
2006 if (pim->type != ((PIM_VERSION << 4) | (PIM_REGISTER)) ||
2007 (pim->flags & PIM_NULL_REGISTER) ||
2008 (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
2009 csum_fold(skb_checksum(skb, 0, skb->len, 0))))
2012 mrt = ipmr_rt_fib_lookup(net, skb);
2015 if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2023 static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2024 struct mfc_cache *c, struct rtmsg *rtm)
2027 struct rtnexthop *nhp;
2028 u8 *b = skb_tail_pointer(skb);
2029 struct rtattr *mp_head;
2031 /* If cache is unresolved, don't try to parse IIF and OIF */
2032 if (c->mfc_parent >= MAXVIFS)
2035 if (VIF_EXISTS(mrt, c->mfc_parent))
2036 RTA_PUT(skb, RTA_IIF, 4, &mrt->vif_table[c->mfc_parent].dev->ifindex);
2038 mp_head = (struct rtattr *)skb_put(skb, RTA_LENGTH(0));
2040 for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
2041 if (VIF_EXISTS(mrt, ct) && c->mfc_un.res.ttls[ct] < 255) {
2042 if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
2043 goto rtattr_failure;
2044 nhp = (struct rtnexthop *)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
2045 nhp->rtnh_flags = 0;
2046 nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
2047 nhp->rtnh_ifindex = mrt->vif_table[ct].dev->ifindex;
2048 nhp->rtnh_len = sizeof(*nhp);
2051 mp_head->rta_type = RTA_MULTIPATH;
2052 mp_head->rta_len = skb_tail_pointer(skb) - (u8 *)mp_head;
2053 rtm->rtm_type = RTN_MULTICAST;
2061 int ipmr_get_route(struct net *net, struct sk_buff *skb,
2062 __be32 saddr, __be32 daddr,
2063 struct rtmsg *rtm, int nowait, u32 portid)
2065 struct mfc_cache *cache;
2066 struct mr_table *mrt;
2069 mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2074 cache = ipmr_cache_find(mrt, saddr, daddr);
2076 if (cache == NULL) {
2077 struct sk_buff *skb2;
2079 struct net_device *dev;
2088 read_lock(&mrt_lock);
2090 vif = ipmr_find_vif(mrt, dev);
2092 read_unlock(&mrt_lock);
2096 skb2 = skb_clone(skb, GFP_ATOMIC);
2098 read_unlock(&mrt_lock);
2103 NETLINK_CB(skb2).pid = portid;
2104 skb_push(skb2, sizeof(struct iphdr));
2105 skb_reset_network_header(skb2);
2107 iph->ihl = sizeof(struct iphdr) >> 2;
2111 err = ipmr_cache_unresolved(mrt, vif, skb2);
2112 read_unlock(&mrt_lock);
2117 read_lock(&mrt_lock);
2118 if (!nowait && (rtm->rtm_flags & RTM_F_NOTIFY))
2119 cache->mfc_flags |= MFC_NOTIFY;
2120 err = __ipmr_fill_mroute(mrt, skb, cache, rtm);
2121 read_unlock(&mrt_lock);
2126 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2127 u32 pid, u32 seq, struct mfc_cache *c)
2129 struct nlmsghdr *nlh;
2132 nlh = nlmsg_put(skb, pid, seq, RTM_NEWROUTE, sizeof(*rtm), NLM_F_MULTI);
2136 rtm = nlmsg_data(nlh);
2137 rtm->rtm_family = RTNL_FAMILY_IPMR;
2138 rtm->rtm_dst_len = 32;
2139 rtm->rtm_src_len = 32;
2141 rtm->rtm_table = mrt->id;
2142 NLA_PUT_U32(skb, RTA_TABLE, mrt->id);
2143 rtm->rtm_type = RTN_MULTICAST;
2144 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2145 rtm->rtm_protocol = RTPROT_UNSPEC;
2148 NLA_PUT_BE32(skb, RTA_SRC, c->mfc_origin);
2149 NLA_PUT_BE32(skb, RTA_DST, c->mfc_mcastgrp);
2151 if (__ipmr_fill_mroute(mrt, skb, c, rtm) < 0)
2152 goto nla_put_failure;
2154 return nlmsg_end(skb, nlh);
2157 nlmsg_cancel(skb, nlh);
2161 static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2163 struct net *net = sock_net(skb->sk);
2164 struct mr_table *mrt;
2165 struct mfc_cache *mfc;
2166 unsigned int t = 0, s_t;
2167 unsigned int h = 0, s_h;
2168 unsigned int e = 0, s_e;
2175 ipmr_for_each_table(mrt, net) {
2180 for (h = s_h; h < MFC_LINES; h++) {
2181 list_for_each_entry_rcu(mfc, &mrt->mfc_cache_array[h], list) {
2184 if (ipmr_fill_mroute(mrt, skb,
2185 NETLINK_CB(cb->skb).pid,
2208 #ifdef CONFIG_PROC_FS
2210 * The /proc interfaces to multicast routing :
2211 * /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2213 struct ipmr_vif_iter {
2214 struct seq_net_private p;
2215 struct mr_table *mrt;
2219 static struct vif_device *ipmr_vif_seq_idx(struct net *net,
2220 struct ipmr_vif_iter *iter,
2223 struct mr_table *mrt = iter->mrt;
2225 for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
2226 if (!VIF_EXISTS(mrt, iter->ct))
2229 return &mrt->vif_table[iter->ct];
2234 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2235 __acquires(mrt_lock)
2237 struct ipmr_vif_iter *iter = seq->private;
2238 struct net *net = seq_file_net(seq);
2239 struct mr_table *mrt;
2241 mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2243 return ERR_PTR(-ENOENT);
2247 read_lock(&mrt_lock);
2248 return *pos ? ipmr_vif_seq_idx(net, seq->private, *pos - 1)
2252 static void *ipmr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2254 struct ipmr_vif_iter *iter = seq->private;
2255 struct net *net = seq_file_net(seq);
2256 struct mr_table *mrt = iter->mrt;
2259 if (v == SEQ_START_TOKEN)
2260 return ipmr_vif_seq_idx(net, iter, 0);
2262 while (++iter->ct < mrt->maxvif) {
2263 if (!VIF_EXISTS(mrt, iter->ct))
2265 return &mrt->vif_table[iter->ct];
2270 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2271 __releases(mrt_lock)
2273 read_unlock(&mrt_lock);
2276 static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2278 struct ipmr_vif_iter *iter = seq->private;
2279 struct mr_table *mrt = iter->mrt;
2281 if (v == SEQ_START_TOKEN) {
2283 "Interface BytesIn PktsIn BytesOut PktsOut Flags Local Remote\n");
2285 const struct vif_device *vif = v;
2286 const char *name = vif->dev ? vif->dev->name : "none";
2289 "%2Zd %-10s %8ld %7ld %8ld %7ld %05X %08X %08X\n",
2290 vif - mrt->vif_table,
2291 name, vif->bytes_in, vif->pkt_in,
2292 vif->bytes_out, vif->pkt_out,
2293 vif->flags, vif->local, vif->remote);
2298 static const struct seq_operations ipmr_vif_seq_ops = {
2299 .start = ipmr_vif_seq_start,
2300 .next = ipmr_vif_seq_next,
2301 .stop = ipmr_vif_seq_stop,
2302 .show = ipmr_vif_seq_show,
2305 static int ipmr_vif_open(struct inode *inode, struct file *file)
2307 return seq_open_net(inode, file, &ipmr_vif_seq_ops,
2308 sizeof(struct ipmr_vif_iter));
2311 static const struct file_operations ipmr_vif_fops = {
2312 .owner = THIS_MODULE,
2313 .open = ipmr_vif_open,
2315 .llseek = seq_lseek,
2316 .release = seq_release_net,
2319 struct ipmr_mfc_iter {
2320 struct seq_net_private p;
2321 struct mr_table *mrt;
2322 struct list_head *cache;
2327 static struct mfc_cache *ipmr_mfc_seq_idx(struct net *net,
2328 struct ipmr_mfc_iter *it, loff_t pos)
2330 struct mr_table *mrt = it->mrt;
2331 struct mfc_cache *mfc;
2334 for (it->ct = 0; it->ct < MFC_LINES; it->ct++) {
2335 it->cache = &mrt->mfc_cache_array[it->ct];
2336 list_for_each_entry_rcu(mfc, it->cache, list)
2342 spin_lock_bh(&mfc_unres_lock);
2343 it->cache = &mrt->mfc_unres_queue;
2344 list_for_each_entry(mfc, it->cache, list)
2347 spin_unlock_bh(&mfc_unres_lock);
2354 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2356 struct ipmr_mfc_iter *it = seq->private;
2357 struct net *net = seq_file_net(seq);
2358 struct mr_table *mrt;
2360 mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2362 return ERR_PTR(-ENOENT);
2367 return *pos ? ipmr_mfc_seq_idx(net, seq->private, *pos - 1)
2371 static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2373 struct mfc_cache *mfc = v;
2374 struct ipmr_mfc_iter *it = seq->private;
2375 struct net *net = seq_file_net(seq);
2376 struct mr_table *mrt = it->mrt;
2380 if (v == SEQ_START_TOKEN)
2381 return ipmr_mfc_seq_idx(net, seq->private, 0);
2383 if (mfc->list.next != it->cache)
2384 return list_entry(mfc->list.next, struct mfc_cache, list);
2386 if (it->cache == &mrt->mfc_unres_queue)
2389 BUG_ON(it->cache != &mrt->mfc_cache_array[it->ct]);
2391 while (++it->ct < MFC_LINES) {
2392 it->cache = &mrt->mfc_cache_array[it->ct];
2393 if (list_empty(it->cache))
2395 return list_first_entry(it->cache, struct mfc_cache, list);
2398 /* exhausted cache_array, show unresolved */
2400 it->cache = &mrt->mfc_unres_queue;
2403 spin_lock_bh(&mfc_unres_lock);
2404 if (!list_empty(it->cache))
2405 return list_first_entry(it->cache, struct mfc_cache, list);
2408 spin_unlock_bh(&mfc_unres_lock);
2414 static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
2416 struct ipmr_mfc_iter *it = seq->private;
2417 struct mr_table *mrt = it->mrt;
2419 if (it->cache == &mrt->mfc_unres_queue)
2420 spin_unlock_bh(&mfc_unres_lock);
2421 else if (it->cache == &mrt->mfc_cache_array[it->ct])
2425 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2429 if (v == SEQ_START_TOKEN) {
2431 "Group Origin Iif Pkts Bytes Wrong Oifs\n");
2433 const struct mfc_cache *mfc = v;
2434 const struct ipmr_mfc_iter *it = seq->private;
2435 const struct mr_table *mrt = it->mrt;
2437 seq_printf(seq, "%08X %08X %-3hd",
2438 (__force u32) mfc->mfc_mcastgrp,
2439 (__force u32) mfc->mfc_origin,
2442 if (it->cache != &mrt->mfc_unres_queue) {
2443 seq_printf(seq, " %8lu %8lu %8lu",
2444 mfc->mfc_un.res.pkt,
2445 mfc->mfc_un.res.bytes,
2446 mfc->mfc_un.res.wrong_if);
2447 for (n = mfc->mfc_un.res.minvif;
2448 n < mfc->mfc_un.res.maxvif; n++) {
2449 if (VIF_EXISTS(mrt, n) &&
2450 mfc->mfc_un.res.ttls[n] < 255)
2453 n, mfc->mfc_un.res.ttls[n]);
2456 /* unresolved mfc_caches don't contain
2457 * pkt, bytes and wrong_if values
2459 seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
2461 seq_putc(seq, '\n');
2466 static const struct seq_operations ipmr_mfc_seq_ops = {
2467 .start = ipmr_mfc_seq_start,
2468 .next = ipmr_mfc_seq_next,
2469 .stop = ipmr_mfc_seq_stop,
2470 .show = ipmr_mfc_seq_show,
2473 static int ipmr_mfc_open(struct inode *inode, struct file *file)
2475 return seq_open_net(inode, file, &ipmr_mfc_seq_ops,
2476 sizeof(struct ipmr_mfc_iter));
2479 static const struct file_operations ipmr_mfc_fops = {
2480 .owner = THIS_MODULE,
2481 .open = ipmr_mfc_open,
2483 .llseek = seq_lseek,
2484 .release = seq_release_net,
2488 #ifdef CONFIG_IP_PIMSM_V2
2489 static const struct net_protocol pim_protocol = {
2497 * Setup for IP multicast routing
2499 static int __net_init ipmr_net_init(struct net *net)
2503 err = ipmr_rules_init(net);
2507 #ifdef CONFIG_PROC_FS
2509 if (!proc_net_fops_create(net, "ip_mr_vif", 0, &ipmr_vif_fops))
2511 if (!proc_net_fops_create(net, "ip_mr_cache", 0, &ipmr_mfc_fops))
2512 goto proc_cache_fail;
2516 #ifdef CONFIG_PROC_FS
2518 proc_net_remove(net, "ip_mr_vif");
2520 ipmr_rules_exit(net);
2526 static void __net_exit ipmr_net_exit(struct net *net)
2528 #ifdef CONFIG_PROC_FS
2529 proc_net_remove(net, "ip_mr_cache");
2530 proc_net_remove(net, "ip_mr_vif");
2532 ipmr_rules_exit(net);
2535 static struct pernet_operations ipmr_net_ops = {
2536 .init = ipmr_net_init,
2537 .exit = ipmr_net_exit,
2540 int __init ip_mr_init(void)
2544 mrt_cachep = kmem_cache_create("ip_mrt_cache",
2545 sizeof(struct mfc_cache),
2546 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
2551 err = register_pernet_subsys(&ipmr_net_ops);
2553 goto reg_pernet_fail;
2555 err = register_netdevice_notifier(&ip_mr_notifier);
2557 goto reg_notif_fail;
2558 #ifdef CONFIG_IP_PIMSM_V2
2559 if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
2560 printk(KERN_ERR "ip_mr_init: can't add PIM protocol\n");
2562 goto add_proto_fail;
2565 rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
2566 NULL, ipmr_rtm_dumproute, NULL);
2569 #ifdef CONFIG_IP_PIMSM_V2
2571 unregister_netdevice_notifier(&ip_mr_notifier);
2574 unregister_pernet_subsys(&ipmr_net_ops);
2576 kmem_cache_destroy(mrt_cachep);