Pileus Git - ~andy/linux/blob - net/ipv4/ipmr.c

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