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