net/ipv4/ipmr.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      IP multicast routing support for mrouted 3.6/3.8
   4  *
   5  *              (c) 1995 Alan Cox, <alan@lxorguk.ukuu.org.uk>
   6  *        Linux Consultancy and Custom Driver Development
   7  *
   8  *      Fixes:
   9  *      Michael Chastain        :       Incorrect size of copying.
  10  *      Alan Cox                :       Added the cache manager code
  11  *      Alan Cox                :       Fixed the clone/copy bug and device race.
  12  *      Mike McLagan            :       Routing by source
  13  *      Malcolm Beattie         :       Buffer handling fixes.
  14  *      Alexey Kuznetsov        :       Double buffer free and other fixes.
  15  *      SVR Anand               :       Fixed several multicast bugs and problems.
  16  *      Alexey Kuznetsov        :       Status, optimisations and more.
  17  *      Brad Parker             :       Better behaviour on mrouted upcall
  18  *                                      overflow.
  19  *      Carlos Picoto           :       PIMv1 Support
  20  *      Pavlin Ivanov Radoslavov:       PIMv2 Registers must checksum only PIM header
  21  *                                      Relax this requirement to work with older peers.
  22  */
  23
  24 #include <linux/uaccess.h>
  25 #include <linux/types.h>
  26 #include <linux/cache.h>
  27 #include <linux/capability.h>
  28 #include <linux/errno.h>
  29 #include <linux/mm.h>
  30 #include <linux/kernel.h>
  31 #include <linux/fcntl.h>
  32 #include <linux/stat.h>
  33 #include <linux/socket.h>
  34 #include <linux/in.h>
  35 #include <linux/inet.h>
  36 #include <linux/netdevice.h>
  37 #include <linux/inetdevice.h>
  38 #include <linux/igmp.h>
  39 #include <linux/proc_fs.h>
  40 #include <linux/seq_file.h>
  41 #include <linux/mroute.h>
  42 #include <linux/init.h>
  43 #include <linux/if_ether.h>
  44 #include <linux/slab.h>
  45 #include <net/net_namespace.h>
  46 #include <net/ip.h>
  47 #include <net/protocol.h>
  48 #include <linux/skbuff.h>
  49 #include <net/route.h>
  50 #include <net/icmp.h>
  51 #include <net/udp.h>
  52 #include <net/raw.h>
  53 #include <linux/notifier.h>
  54 #include <linux/if_arp.h>
  55 #include <linux/netfilter_ipv4.h>
  56 #include <linux/compat.h>
  57 #include <linux/export.h>
  58 #include <linux/rhashtable.h>
  59 #include <net/ip_tunnels.h>
  60 #include <net/checksum.h>
  61 #include <net/netlink.h>
  62 #include <net/fib_rules.h>
  63 #include <linux/netconf.h>
  64 #include <net/rtnh.h>
  65
  66 #include <linux/nospec.h>
  67
  68 struct ipmr_rule {
  69         struct fib_rule         common;
  70 };
  71
  72 struct ipmr_result {
  73         struct mr_table         *mrt;
  74 };
  75
  76 /* Big lock, protecting vif table, mrt cache and mroute socket state.
  77  * Note that the changes are semaphored via rtnl_lock.
  78  */
  79
  80 static DEFINE_SPINLOCK(mrt_lock);
  81
  82 static struct net_device *vif_dev_read(const struct vif_device *vif)
  83 {
  84         return rcu_dereference(vif->dev);
  85 }
  86
  87 /* Multicast router control variables */
  88
  89 /* Special spinlock for queue of unresolved entries */
  90 static DEFINE_SPINLOCK(mfc_unres_lock);
  91
  92 /* We return to original Alan's scheme. Hash table of resolved
  93  * entries is changed only in process context and protected
  94  * with weak lock mrt_lock. Queue of unresolved entries is protected
  95  * with strong spinlock mfc_unres_lock.
  96  *
  97  * In this case data path is free of exclusive locks at all.
  98  */
  99
 100 static struct kmem_cache *mrt_cachep __ro_after_init;
 101
 102 static struct mr_table *ipmr_new_table(struct net *net, u32 id);
 103 static void ipmr_free_table(struct mr_table *mrt);
 104
 105 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
 106                           struct net_device *dev, struct sk_buff *skb,
 107                           struct mfc_cache *cache, int local);
 108 static int ipmr_cache_report(const struct mr_table *mrt,
 109                              struct sk_buff *pkt, vifi_t vifi, int assert);
 110 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
 111                                  int cmd);
 112 static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt);
 113 static void mroute_clean_tables(struct mr_table *mrt, int flags);
 114 static void ipmr_expire_process(struct timer_list *t);
 115
 116 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 117 #define ipmr_for_each_table(mrt, net)                                   \
 118         list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list,        \
 119                                 lockdep_rtnl_is_held() ||               \
 120                                 list_empty(&net->ipv4.mr_tables))
 121
 122 static struct mr_table *ipmr_mr_table_iter(struct net *net,
 123                                            struct mr_table *mrt)
 124 {
 125         struct mr_table *ret;
 126
 127         if (!mrt)
 128                 ret = list_entry_rcu(net->ipv4.mr_tables.next,
 129                                      struct mr_table, list);
 130         else
 131                 ret = list_entry_rcu(mrt->list.next,
 132                                      struct mr_table, list);
 133
 134         if (&ret->list == &net->ipv4.mr_tables)
 135                 return NULL;
 136         return ret;
 137 }
 138
 139 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 140 {
 141         struct mr_table *mrt;
 142
 143         ipmr_for_each_table(mrt, net) {
 144                 if (mrt->id == id)
 145                         return mrt;
 146         }
 147         return NULL;
 148 }
 149
 150 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 151                            struct mr_table **mrt)
 152 {
 153         int err;
 154         struct ipmr_result res;
 155         struct fib_lookup_arg arg = {
 156                 .result = &res,
 157                 .flags = FIB_LOOKUP_NOREF,
 158         };
 159
 160         /* update flow if oif or iif point to device enslaved to l3mdev */
 161         l3mdev_update_flow(net, flowi4_to_flowi(flp4));
 162
 163         err = fib_rules_lookup(net->ipv4.mr_rules_ops,
 164                                flowi4_to_flowi(flp4), 0, &arg);
 165         if (err < 0)
 166                 return err;
 167         *mrt = res.mrt;
 168         return 0;
 169 }
 170
 171 static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
 172                             int flags, struct fib_lookup_arg *arg)
 173 {
 174         struct ipmr_result *res = arg->result;
 175         struct mr_table *mrt;
 176
 177         switch (rule->action) {
 178         case FR_ACT_TO_TBL:
 179                 break;
 180         case FR_ACT_UNREACHABLE:
 181                 return -ENETUNREACH;
 182         case FR_ACT_PROHIBIT:
 183                 return -EACCES;
 184         case FR_ACT_BLACKHOLE:
 185         default:
 186                 return -EINVAL;
 187         }
 188
 189         arg->table = fib_rule_get_table(rule, arg);
 190
 191         mrt = ipmr_get_table(rule->fr_net, arg->table);
 192         if (!mrt)
 193                 return -EAGAIN;
 194         res->mrt = mrt;
 195         return 0;
 196 }
 197
 198 static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
 199 {
 200         return 1;
 201 }
 202
 203 static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
 204                                struct fib_rule_hdr *frh, struct nlattr **tb,
 205                                struct netlink_ext_ack *extack)
 206 {
 207         return 0;
 208 }
 209
 210 static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
 211                              struct nlattr **tb)
 212 {
 213         return 1;
 214 }
 215
 216 static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
 217                           struct fib_rule_hdr *frh)
 218 {
 219         frh->dst_len = 0;
 220         frh->src_len = 0;
 221         frh->tos     = 0;
 222         return 0;
 223 }
 224
 225 static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
 226         .family         = RTNL_FAMILY_IPMR,
 227         .rule_size      = sizeof(struct ipmr_rule),
 228         .addr_size      = sizeof(u32),
 229         .action         = ipmr_rule_action,
 230         .match          = ipmr_rule_match,
 231         .configure      = ipmr_rule_configure,
 232         .compare        = ipmr_rule_compare,
 233         .fill           = ipmr_rule_fill,
 234         .nlgroup        = RTNLGRP_IPV4_RULE,
 235         .owner          = THIS_MODULE,
 236 };
 237
 238 static int __net_init ipmr_rules_init(struct net *net)
 239 {
 240         struct fib_rules_ops *ops;
 241         struct mr_table *mrt;
 242         int err;
 243
 244         ops = fib_rules_register(&ipmr_rules_ops_template, net);
 245         if (IS_ERR(ops))
 246                 return PTR_ERR(ops);
 247
 248         INIT_LIST_HEAD(&net->ipv4.mr_tables);
 249
 250         mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 251         if (IS_ERR(mrt)) {
 252                 err = PTR_ERR(mrt);
 253                 goto err1;
 254         }
 255
 256         err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
 257         if (err < 0)
 258                 goto err2;
 259
 260         net->ipv4.mr_rules_ops = ops;
 261         return 0;
 262
 263 err2:
 264         rtnl_lock();
 265         ipmr_free_table(mrt);
 266         rtnl_unlock();
 267 err1:
 268         fib_rules_unregister(ops);
 269         return err;
 270 }
 271
 272 static void __net_exit ipmr_rules_exit(struct net *net)
 273 {
 274         struct mr_table *mrt, *next;
 275
 276         ASSERT_RTNL();
 277         list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
 278                 list_del(&mrt->list);
 279                 ipmr_free_table(mrt);
 280         }
 281         fib_rules_unregister(net->ipv4.mr_rules_ops);
 282 }
 283
 284 static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
 285                            struct netlink_ext_ack *extack)
 286 {
 287         return fib_rules_dump(net, nb, RTNL_FAMILY_IPMR, extack);
 288 }
 289
 290 static unsigned int ipmr_rules_seq_read(struct net *net)
 291 {
 292         return fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
 293 }
 294
 295 bool ipmr_rule_default(const struct fib_rule *rule)
 296 {
 297         return fib_rule_matchall(rule) && rule->table == RT_TABLE_DEFAULT;
 298 }
 299 EXPORT_SYMBOL(ipmr_rule_default);
 300 #else
 301 #define ipmr_for_each_table(mrt, net) \
 302         for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
 303
 304 static struct mr_table *ipmr_mr_table_iter(struct net *net,
 305                                            struct mr_table *mrt)
 306 {
 307         if (!mrt)
 308                 return net->ipv4.mrt;
 309         return NULL;
 310 }
 311
 312 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 313 {
 314         return net->ipv4.mrt;
 315 }
 316
 317 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 318                            struct mr_table **mrt)
 319 {
 320         *mrt = net->ipv4.mrt;
 321         return 0;
 322 }
 323
 324 static int __net_init ipmr_rules_init(struct net *net)
 325 {
 326         struct mr_table *mrt;
 327
 328         mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 329         if (IS_ERR(mrt))
 330                 return PTR_ERR(mrt);
 331         net->ipv4.mrt = mrt;
 332         return 0;
 333 }
 334
 335 static void __net_exit ipmr_rules_exit(struct net *net)
 336 {
 337         ASSERT_RTNL();
 338         ipmr_free_table(net->ipv4.mrt);
 339         net->ipv4.mrt = NULL;
 340 }
 341
 342 static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
 343                            struct netlink_ext_ack *extack)
 344 {
 345         return 0;
 346 }
 347
 348 static unsigned int ipmr_rules_seq_read(struct net *net)
 349 {
 350         return 0;
 351 }
 352
 353 bool ipmr_rule_default(const struct fib_rule *rule)
 354 {
 355         return true;
 356 }
 357 EXPORT_SYMBOL(ipmr_rule_default);
 358 #endif
 359
 360 static inline int ipmr_hash_cmp(struct rhashtable_compare_arg *arg,
 361                                 const void *ptr)
 362 {
 363         const struct mfc_cache_cmp_arg *cmparg = arg->key;
 364         const struct mfc_cache *c = ptr;
 365
 366         return cmparg->mfc_mcastgrp != c->mfc_mcastgrp ||
 367                cmparg->mfc_origin != c->mfc_origin;
 368 }
 369
 370 static const struct rhashtable_params ipmr_rht_params = {
 371         .head_offset = offsetof(struct mr_mfc, mnode),
 372         .key_offset = offsetof(struct mfc_cache, cmparg),
 373         .key_len = sizeof(struct mfc_cache_cmp_arg),
 374         .nelem_hint = 3,
 375         .obj_cmpfn = ipmr_hash_cmp,
 376         .automatic_shrinking = true,
 377 };
 378
 379 static void ipmr_new_table_set(struct mr_table *mrt,
 380                                struct net *net)
 381 {
 382 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 383         list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
 384 #endif
 385 }
 386
 387 static struct mfc_cache_cmp_arg ipmr_mr_table_ops_cmparg_any = {
 388         .mfc_mcastgrp = htonl(INADDR_ANY),
 389         .mfc_origin = htonl(INADDR_ANY),
 390 };
 391
 392 static struct mr_table_ops ipmr_mr_table_ops = {
 393         .rht_params = &ipmr_rht_params,
 394         .cmparg_any = &ipmr_mr_table_ops_cmparg_any,
 395 };
 396
 397 static struct mr_table *ipmr_new_table(struct net *net, u32 id)
 398 {
 399         struct mr_table *mrt;
 400
 401         /* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) */
 402         if (id != RT_TABLE_DEFAULT && id >= 1000000000)
 403                 return ERR_PTR(-EINVAL);
 404
 405         mrt = ipmr_get_table(net, id);
 406         if (mrt)
 407                 return mrt;
 408
 409         return mr_table_alloc(net, id, &ipmr_mr_table_ops,
 410                               ipmr_expire_process, ipmr_new_table_set);
 411 }
 412
 413 static void ipmr_free_table(struct mr_table *mrt)
 414 {
 415         del_timer_sync(&mrt->ipmr_expire_timer);
 416         mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC |
 417                                  MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC);
 418         rhltable_destroy(&mrt->mfc_hash);
 419         kfree(mrt);
 420 }
 421
 422 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
 423
 424 /* Initialize ipmr pimreg/tunnel in_device */
 425 static bool ipmr_init_vif_indev(const struct net_device *dev)
 426 {
 427         struct in_device *in_dev;
 428
 429         ASSERT_RTNL();
 430
 431         in_dev = __in_dev_get_rtnl(dev);
 432         if (!in_dev)
 433                 return false;
 434         ipv4_devconf_setall(in_dev);
 435         neigh_parms_data_state_setall(in_dev->arp_parms);
 436         IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
 437
 438         return true;
 439 }
 440
 441 static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
 442 {
 443         struct net_device *tunnel_dev, *new_dev;
 444         struct ip_tunnel_parm p = { };
 445         int err;
 446
 447         tunnel_dev = __dev_get_by_name(net, "tunl0");
 448         if (!tunnel_dev)
 449                 goto out;
 450
 451         p.iph.daddr = v->vifc_rmt_addr.s_addr;
 452         p.iph.saddr = v->vifc_lcl_addr.s_addr;
 453         p.iph.version = 4;
 454         p.iph.ihl = 5;
 455         p.iph.protocol = IPPROTO_IPIP;
 456         sprintf(p.name, "dvmrp%d", v->vifc_vifi);
 457
 458         if (!tunnel_dev->netdev_ops->ndo_tunnel_ctl)
 459                 goto out;
 460         err = tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p,
 461                         SIOCADDTUNNEL);
 462         if (err)
 463                 goto out;
 464
 465         new_dev = __dev_get_by_name(net, p.name);
 466         if (!new_dev)
 467                 goto out;
 468
 469         new_dev->flags |= IFF_MULTICAST;
 470         if (!ipmr_init_vif_indev(new_dev))
 471                 goto out_unregister;
 472         if (dev_open(new_dev, NULL))
 473                 goto out_unregister;
 474         dev_hold(new_dev);
 475         err = dev_set_allmulti(new_dev, 1);
 476         if (err) {
 477                 dev_close(new_dev);
 478                 tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p,
 479                                 SIOCDELTUNNEL);
 480                 dev_put(new_dev);
 481                 new_dev = ERR_PTR(err);
 482         }
 483         return new_dev;
 484
 485 out_unregister:
 486         unregister_netdevice(new_dev);
 487 out:
 488         return ERR_PTR(-ENOBUFS);
 489 }
 490
 491 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
 492 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
 493 {
 494         struct net *net = dev_net(dev);
 495         struct mr_table *mrt;
 496         struct flowi4 fl4 = {
 497                 .flowi4_oif     = dev->ifindex,
 498                 .flowi4_iif     = skb->skb_iif ? : LOOPBACK_IFINDEX,
 499                 .flowi4_mark    = skb->mark,
 500         };
 501         int err;
 502
 503         err = ipmr_fib_lookup(net, &fl4, &mrt);
 504         if (err < 0) {
 505                 kfree_skb(skb);
 506                 return err;
 507         }
 508
 509         dev->stats.tx_bytes += skb->len;
 510         dev->stats.tx_packets++;
 511         rcu_read_lock();
 512
 513         /* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */
 514         ipmr_cache_report(mrt, skb, READ_ONCE(mrt->mroute_reg_vif_num),
 515                           IGMPMSG_WHOLEPKT);
 516
 517         rcu_read_unlock();
 518         kfree_skb(skb);
 519         return NETDEV_TX_OK;
 520 }
 521
 522 static int reg_vif_get_iflink(const struct net_device *dev)
 523 {
 524         return 0;
 525 }
 526
 527 static const struct net_device_ops reg_vif_netdev_ops = {
 528         .ndo_start_xmit = reg_vif_xmit,
 529         .ndo_get_iflink = reg_vif_get_iflink,
 530 };
 531
 532 static void reg_vif_setup(struct net_device *dev)
 533 {
 534         dev->type               = ARPHRD_PIMREG;
 535         dev->mtu                = ETH_DATA_LEN - sizeof(struct iphdr) - 8;
 536         dev->flags              = IFF_NOARP;
 537         dev->netdev_ops         = &reg_vif_netdev_ops;
 538         dev->needs_free_netdev  = true;
 539         dev->features           |= NETIF_F_NETNS_LOCAL;
 540 }
 541
 542 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
 543 {
 544         struct net_device *dev;
 545         char name[IFNAMSIZ];
 546
 547         if (mrt->id == RT_TABLE_DEFAULT)
 548                 sprintf(name, "pimreg");
 549         else
 550                 sprintf(name, "pimreg%u", mrt->id);
 551
 552         dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
 553
 554         if (!dev)
 555                 return NULL;
 556
 557         dev_net_set(dev, net);
 558
 559         if (register_netdevice(dev)) {
 560                 free_netdev(dev);
 561                 return NULL;
 562         }
 563
 564         if (!ipmr_init_vif_indev(dev))
 565                 goto failure;
 566         if (dev_open(dev, NULL))
 567                 goto failure;
 568
 569         dev_hold(dev);
 570
 571         return dev;
 572
 573 failure:
 574         unregister_netdevice(dev);
 575         return NULL;
 576 }
 577
 578 /* called with rcu_read_lock() */
 579 static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
 580                      unsigned int pimlen)
 581 {
 582         struct net_device *reg_dev = NULL;
 583         struct iphdr *encap;
 584         int vif_num;
 585
 586         encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
 587         /* Check that:
 588          * a. packet is really sent to a multicast group
 589          * b. packet is not a NULL-REGISTER
 590          * c. packet is not truncated
 591          */
 592         if (!ipv4_is_multicast(encap->daddr) ||
 593             encap->tot_len == 0 ||
 594             ntohs(encap->tot_len) + pimlen > skb->len)
 595                 return 1;
 596
 597         /* Pairs with WRITE_ONCE() in vif_add()/vid_delete() */
 598         vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
 599         if (vif_num >= 0)
 600                 reg_dev = vif_dev_read(&mrt->vif_table[vif_num]);
 601         if (!reg_dev)
 602                 return 1;
 603
 604         skb->mac_header = skb->network_header;
 605         skb_pull(skb, (u8 *)encap - skb->data);
 606         skb_reset_network_header(skb);
 607         skb->protocol = htons(ETH_P_IP);
 608         skb->ip_summed = CHECKSUM_NONE;
 609
 610         skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
 611
 612         netif_rx(skb);
 613
 614         return NET_RX_SUCCESS;
 615 }
 616 #else
 617 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
 618 {
 619         return NULL;
 620 }
 621 #endif
 622
 623 static int call_ipmr_vif_entry_notifiers(struct net *net,
 624                                          enum fib_event_type event_type,
 625                                          struct vif_device *vif,
 626                                          struct net_device *vif_dev,
 627                                          vifi_t vif_index, u32 tb_id)
 628 {
 629         return mr_call_vif_notifiers(net, RTNL_FAMILY_IPMR, event_type,
 630                                      vif, vif_dev, vif_index, tb_id,
 631                                      &net->ipv4.ipmr_seq);
 632 }
 633
 634 static int call_ipmr_mfc_entry_notifiers(struct net *net,
 635                                          enum fib_event_type event_type,
 636                                          struct mfc_cache *mfc, u32 tb_id)
 637 {
 638         return mr_call_mfc_notifiers(net, RTNL_FAMILY_IPMR, event_type,
 639                                      &mfc->_c, tb_id, &net->ipv4.ipmr_seq);
 640 }
 641
 642 /**
 643  *      vif_delete - Delete a VIF entry
 644  *      @mrt: Table to delete from
 645  *      @vifi: VIF identifier to delete
 646  *      @notify: Set to 1, if the caller is a notifier_call
 647  *      @head: if unregistering the VIF, place it on this queue
 648  */
 649 static int vif_delete(struct mr_table *mrt, int vifi, int notify,
 650                       struct list_head *head)
 651 {
 652         struct net *net = read_pnet(&mrt->net);
 653         struct vif_device *v;
 654         struct net_device *dev;
 655         struct in_device *in_dev;
 656
 657         if (vifi < 0 || vifi >= mrt->maxvif)
 658                 return -EADDRNOTAVAIL;
 659
 660         v = &mrt->vif_table[vifi];
 661
 662         dev = rtnl_dereference(v->dev);
 663         if (!dev)
 664                 return -EADDRNOTAVAIL;
 665
 666         spin_lock(&mrt_lock);
 667         call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_DEL, v, dev,
 668                                       vifi, mrt->id);
 669         RCU_INIT_POINTER(v->dev, NULL);
 670
 671         if (vifi == mrt->mroute_reg_vif_num) {
 672                 /* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */
 673                 WRITE_ONCE(mrt->mroute_reg_vif_num, -1);
 674         }
 675         if (vifi + 1 == mrt->maxvif) {
 676                 int tmp;
 677
 678                 for (tmp = vifi - 1; tmp >= 0; tmp--) {
 679                         if (VIF_EXISTS(mrt, tmp))
 680                                 break;
 681                 }
 682                 WRITE_ONCE(mrt->maxvif, tmp + 1);
 683         }
 684
 685         spin_unlock(&mrt_lock);
 686
 687         dev_set_allmulti(dev, -1);
 688
 689         in_dev = __in_dev_get_rtnl(dev);
 690         if (in_dev) {
 691                 IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
 692                 inet_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
 693                                             NETCONFA_MC_FORWARDING,
 694                                             dev->ifindex, &in_dev->cnf);
 695                 ip_rt_multicast_event(in_dev);
 696         }
 697
 698         if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
 699                 unregister_netdevice_queue(dev, head);
 700
 701         netdev_put(dev, &v->dev_tracker);
 702         return 0;
 703 }
 704
 705 static void ipmr_cache_free_rcu(struct rcu_head *head)
 706 {
 707         struct mr_mfc *c = container_of(head, struct mr_mfc, rcu);
 708
 709         kmem_cache_free(mrt_cachep, (struct mfc_cache *)c);
 710 }
 711
 712 static void ipmr_cache_free(struct mfc_cache *c)
 713 {
 714         call_rcu(&c->_c.rcu, ipmr_cache_free_rcu);
 715 }
 716
 717 /* Destroy an unresolved cache entry, killing queued skbs
 718  * and reporting error to netlink readers.
 719  */
 720 static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
 721 {
 722         struct net *net = read_pnet(&mrt->net);
 723         struct sk_buff *skb;
 724         struct nlmsgerr *e;
 725
 726         atomic_dec(&mrt->cache_resolve_queue_len);
 727
 728         while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved))) {
 729                 if (ip_hdr(skb)->version == 0) {
 730                         struct nlmsghdr *nlh = skb_pull(skb,
 731                                                         sizeof(struct iphdr));
 732                         nlh->nlmsg_type = NLMSG_ERROR;
 733                         nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
 734                         skb_trim(skb, nlh->nlmsg_len);
 735                         e = nlmsg_data(nlh);
 736                         e->error = -ETIMEDOUT;
 737                         memset(&e->msg, 0, sizeof(e->msg));
 738
 739                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
 740                 } else {
 741                         kfree_skb(skb);
 742                 }
 743         }
 744
 745         ipmr_cache_free(c);
 746 }
 747
 748 /* Timer process for the unresolved queue. */
 749 static void ipmr_expire_process(struct timer_list *t)
 750 {
 751         struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
 752         struct mr_mfc *c, *next;
 753         unsigned long expires;
 754         unsigned long now;
 755
 756         if (!spin_trylock(&mfc_unres_lock)) {
 757                 mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10);
 758                 return;
 759         }
 760
 761         if (list_empty(&mrt->mfc_unres_queue))
 762                 goto out;
 763
 764         now = jiffies;
 765         expires = 10*HZ;
 766
 767         list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
 768                 if (time_after(c->mfc_un.unres.expires, now)) {
 769                         unsigned long interval = c->mfc_un.unres.expires - now;
 770                         if (interval < expires)
 771                                 expires = interval;
 772                         continue;
 773                 }
 774
 775                 list_del(&c->list);
 776                 mroute_netlink_event(mrt, (struct mfc_cache *)c, RTM_DELROUTE);
 777                 ipmr_destroy_unres(mrt, (struct mfc_cache *)c);
 778         }
 779
 780         if (!list_empty(&mrt->mfc_unres_queue))
 781                 mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
 782
 783 out:
 784         spin_unlock(&mfc_unres_lock);
 785 }
 786
 787 /* Fill oifs list. It is called under locked mrt_lock. */
 788 static void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
 789                                    unsigned char *ttls)
 790 {
 791         int vifi;
 792
 793         cache->mfc_un.res.minvif = MAXVIFS;
 794         cache->mfc_un.res.maxvif = 0;
 795         memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
 796
 797         for (vifi = 0; vifi < mrt->maxvif; vifi++) {
 798                 if (VIF_EXISTS(mrt, vifi) &&
 799                     ttls[vifi] && ttls[vifi] < 255) {
 800                         cache->mfc_un.res.ttls[vifi] = ttls[vifi];
 801                         if (cache->mfc_un.res.minvif > vifi)
 802                                 cache->mfc_un.res.minvif = vifi;
 803                         if (cache->mfc_un.res.maxvif <= vifi)
 804                                 cache->mfc_un.res.maxvif = vifi + 1;
 805                 }
 806         }
 807         cache->mfc_un.res.lastuse = jiffies;
 808 }
 809
 810 static int vif_add(struct net *net, struct mr_table *mrt,
 811                    struct vifctl *vifc, int mrtsock)
 812 {
 813         struct netdev_phys_item_id ppid = { };
 814         int vifi = vifc->vifc_vifi;
 815         struct vif_device *v = &mrt->vif_table[vifi];
 816         struct net_device *dev;
 817         struct in_device *in_dev;
 818         int err;
 819
 820         /* Is vif busy ? */
 821         if (VIF_EXISTS(mrt, vifi))
 822                 return -EADDRINUSE;
 823
 824         switch (vifc->vifc_flags) {
 825         case VIFF_REGISTER:
 826                 if (!ipmr_pimsm_enabled())
 827                         return -EINVAL;
 828                 /* Special Purpose VIF in PIM
 829                  * All the packets will be sent to the daemon
 830                  */
 831                 if (mrt->mroute_reg_vif_num >= 0)
 832                         return -EADDRINUSE;
 833                 dev = ipmr_reg_vif(net, mrt);
 834                 if (!dev)
 835                         return -ENOBUFS;
 836                 err = dev_set_allmulti(dev, 1);
 837                 if (err) {
 838                         unregister_netdevice(dev);
 839                         dev_put(dev);
 840                         return err;
 841                 }
 842                 break;
 843         case VIFF_TUNNEL:
 844                 dev = ipmr_new_tunnel(net, vifc);
 845                 if (IS_ERR(dev))
 846                         return PTR_ERR(dev);
 847                 break;
 848         case VIFF_USE_IFINDEX:
 849         case 0:
 850                 if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
 851                         dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
 852                         if (dev && !__in_dev_get_rtnl(dev)) {
 853                                 dev_put(dev);
 854                                 return -EADDRNOTAVAIL;
 855                         }
 856                 } else {
 857                         dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
 858                 }
 859                 if (!dev)
 860                         return -EADDRNOTAVAIL;
 861                 err = dev_set_allmulti(dev, 1);
 862                 if (err) {
 863                         dev_put(dev);
 864                         return err;
 865                 }
 866                 break;
 867         default:
 868                 return -EINVAL;
 869         }
 870
 871         in_dev = __in_dev_get_rtnl(dev);
 872         if (!in_dev) {
 873                 dev_put(dev);
 874                 return -EADDRNOTAVAIL;
 875         }
 876         IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
 877         inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING,
 878                                     dev->ifindex, &in_dev->cnf);
 879         ip_rt_multicast_event(in_dev);
 880
 881         /* Fill in the VIF structures */
 882         vif_device_init(v, dev, vifc->vifc_rate_limit,
 883                         vifc->vifc_threshold,
 884                         vifc->vifc_flags | (!mrtsock ? VIFF_STATIC : 0),
 885                         (VIFF_TUNNEL | VIFF_REGISTER));
 886
 887         err = dev_get_port_parent_id(dev, &ppid, true);
 888         if (err == 0) {
 889                 memcpy(v->dev_parent_id.id, ppid.id, ppid.id_len);
 890                 v->dev_parent_id.id_len = ppid.id_len;
 891         } else {
 892                 v->dev_parent_id.id_len = 0;
 893         }
 894
 895         v->local = vifc->vifc_lcl_addr.s_addr;
 896         v->remote = vifc->vifc_rmt_addr.s_addr;
 897
 898         /* And finish update writing critical data */
 899         spin_lock(&mrt_lock);
 900         rcu_assign_pointer(v->dev, dev);
 901         netdev_tracker_alloc(dev, &v->dev_tracker, GFP_ATOMIC);
 902         if (v->flags & VIFF_REGISTER) {
 903                 /* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */
 904                 WRITE_ONCE(mrt->mroute_reg_vif_num, vifi);
 905         }
 906         if (vifi+1 > mrt->maxvif)
 907                 WRITE_ONCE(mrt->maxvif, vifi + 1);
 908         spin_unlock(&mrt_lock);
 909         call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD, v, dev,
 910                                       vifi, mrt->id);
 911         return 0;
 912 }
 913
 914 /* called with rcu_read_lock() */
 915 static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
 916                                          __be32 origin,
 917                                          __be32 mcastgrp)
 918 {
 919         struct mfc_cache_cmp_arg arg = {
 920                         .mfc_mcastgrp = mcastgrp,
 921                         .mfc_origin = origin
 922         };
 923
 924         return mr_mfc_find(mrt, &arg);
 925 }
 926
 927 /* Look for a (*,G) entry */
 928 static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
 929                                              __be32 mcastgrp, int vifi)
 930 {
 931         struct mfc_cache_cmp_arg arg = {
 932                         .mfc_mcastgrp = mcastgrp,
 933                         .mfc_origin = htonl(INADDR_ANY)
 934         };
 935
 936         if (mcastgrp == htonl(INADDR_ANY))
 937                 return mr_mfc_find_any_parent(mrt, vifi);
 938         return mr_mfc_find_any(mrt, vifi, &arg);
 939 }
 940
 941 /* Look for a (S,G,iif) entry if parent != -1 */
 942 static struct mfc_cache *ipmr_cache_find_parent(struct mr_table *mrt,
 943                                                 __be32 origin, __be32 mcastgrp,
 944                                                 int parent)
 945 {
 946         struct mfc_cache_cmp_arg arg = {
 947                         .mfc_mcastgrp = mcastgrp,
 948                         .mfc_origin = origin,
 949         };
 950
 951         return mr_mfc_find_parent(mrt, &arg, parent);
 952 }
 953
 954 /* Allocate a multicast cache entry */
 955 static struct mfc_cache *ipmr_cache_alloc(void)
 956 {
 957         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
 958
 959         if (c) {
 960                 c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
 961                 c->_c.mfc_un.res.minvif = MAXVIFS;
 962                 c->_c.free = ipmr_cache_free_rcu;
 963                 refcount_set(&c->_c.mfc_un.res.refcount, 1);
 964         }
 965         return c;
 966 }
 967
 968 static struct mfc_cache *ipmr_cache_alloc_unres(void)
 969 {
 970         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
 971
 972         if (c) {
 973                 skb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
 974                 c->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
 975         }
 976         return c;
 977 }
 978
 979 /* A cache entry has gone into a resolved state from queued */
 980 static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
 981                                struct mfc_cache *uc, struct mfc_cache *c)
 982 {
 983         struct sk_buff *skb;
 984         struct nlmsgerr *e;
 985
 986         /* Play the pending entries through our router */
 987         while ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
 988                 if (ip_hdr(skb)->version == 0) {
 989                         struct nlmsghdr *nlh = skb_pull(skb,
 990                                                         sizeof(struct iphdr));
 991
 992                         if (mr_fill_mroute(mrt, skb, &c->_c,
 993                                            nlmsg_data(nlh)) > 0) {
 994                                 nlh->nlmsg_len = skb_tail_pointer(skb) -
 995                                                  (u8 *)nlh;
 996                         } else {
 997                                 nlh->nlmsg_type = NLMSG_ERROR;
 998                                 nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
 999                                 skb_trim(skb, nlh->nlmsg_len);
1000                                 e = nlmsg_data(nlh);
1001                                 e->error = -EMSGSIZE;
1002                                 memset(&e->msg, 0, sizeof(e->msg));
1003                         }
1004
1005                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
1006                 } else {
1007                         rcu_read_lock();
1008                         ip_mr_forward(net, mrt, skb->dev, skb, c, 0);
1009                         rcu_read_unlock();
1010                 }
1011         }
1012 }
1013
1014 /* Bounce a cache query up to mrouted and netlink.
1015  *
1016  * Called under rcu_read_lock().
1017  */
1018 static int ipmr_cache_report(const struct mr_table *mrt,
1019                              struct sk_buff *pkt, vifi_t vifi, int assert)
1020 {
1021         const int ihl = ip_hdrlen(pkt);
1022         struct sock *mroute_sk;
1023         struct igmphdr *igmp;
1024         struct igmpmsg *msg;
1025         struct sk_buff *skb;
1026         int ret;
1027
1028         mroute_sk = rcu_dereference(mrt->mroute_sk);
1029         if (!mroute_sk)
1030                 return -EINVAL;
1031
1032         if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE)
1033                 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
1034         else
1035                 skb = alloc_skb(128, GFP_ATOMIC);
1036
1037         if (!skb)
1038                 return -ENOBUFS;
1039
1040         if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) {
1041                 /* Ugly, but we have no choice with this interface.
1042                  * Duplicate old header, fix ihl, length etc.
1043                  * And all this only to mangle msg->im_msgtype and
1044                  * to set msg->im_mbz to "mbz" :-)
1045                  */
1046                 skb_push(skb, sizeof(struct iphdr));
1047                 skb_reset_network_header(skb);
1048                 skb_reset_transport_header(skb);
1049                 msg = (struct igmpmsg *)skb_network_header(skb);
1050                 memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
1051                 msg->im_msgtype = assert;
1052                 msg->im_mbz = 0;
1053                 if (assert == IGMPMSG_WRVIFWHOLE) {
1054                         msg->im_vif = vifi;
1055                         msg->im_vif_hi = vifi >> 8;
1056                 } else {
1057                         /* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */
1058                         int vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
1059
1060                         msg->im_vif = vif_num;
1061                         msg->im_vif_hi = vif_num >> 8;
1062                 }
1063                 ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
1064                 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
1065                                              sizeof(struct iphdr));
1066         } else {
1067                 /* Copy the IP header */
1068                 skb_set_network_header(skb, skb->len);
1069                 skb_put(skb, ihl);
1070                 skb_copy_to_linear_data(skb, pkt->data, ihl);
1071                 /* Flag to the kernel this is a route add */
1072                 ip_hdr(skb)->protocol = 0;
1073                 msg = (struct igmpmsg *)skb_network_header(skb);
1074                 msg->im_vif = vifi;
1075                 msg->im_vif_hi = vifi >> 8;
1076                 ipv4_pktinfo_prepare(mroute_sk, pkt, false);
1077                 memcpy(skb->cb, pkt->cb, sizeof(skb->cb));
1078                 /* Add our header */
1079                 igmp = skb_put(skb, sizeof(struct igmphdr));
1080                 igmp->type = assert;
1081                 msg->im_msgtype = assert;
1082                 igmp->code = 0;
1083                 ip_hdr(skb)->tot_len = htons(skb->len); /* Fix the length */
1084                 skb->transport_header = skb->network_header;
1085         }
1086
1087         igmpmsg_netlink_event(mrt, skb);
1088
1089         /* Deliver to mrouted */
1090         ret = sock_queue_rcv_skb(mroute_sk, skb);
1091
1092         if (ret < 0) {
1093                 net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1094                 kfree_skb(skb);
1095         }
1096
1097         return ret;
1098 }
1099
1100 /* Queue a packet for resolution. It gets locked cache entry! */
1101 /* Called under rcu_read_lock() */
1102 static int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi,
1103                                  struct sk_buff *skb, struct net_device *dev)
1104 {
1105         const struct iphdr *iph = ip_hdr(skb);
1106         struct mfc_cache *c;
1107         bool found = false;
1108         int err;
1109
1110         spin_lock_bh(&mfc_unres_lock);
1111         list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
1112                 if (c->mfc_mcastgrp == iph->daddr &&
1113                     c->mfc_origin == iph->saddr) {
1114                         found = true;
1115                         break;
1116                 }
1117         }
1118
1119         if (!found) {
1120                 /* Create a new entry if allowable */
1121                 c = ipmr_cache_alloc_unres();
1122                 if (!c) {
1123                         spin_unlock_bh(&mfc_unres_lock);
1124
1125                         kfree_skb(skb);
1126                         return -ENOBUFS;
1127                 }
1128
1129                 /* Fill in the new cache entry */
1130                 c->_c.mfc_parent = -1;
1131                 c->mfc_origin   = iph->saddr;
1132                 c->mfc_mcastgrp = iph->daddr;
1133
1134                 /* Reflect first query at mrouted. */
1135                 err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1136
1137                 if (err < 0) {
1138                         /* If the report failed throw the cache entry
1139                            out - Brad Parker
1140                          */
1141                         spin_unlock_bh(&mfc_unres_lock);
1142
1143                         ipmr_cache_free(c);
1144                         kfree_skb(skb);
1145                         return err;
1146                 }
1147
1148                 atomic_inc(&mrt->cache_resolve_queue_len);
1149                 list_add(&c->_c.list, &mrt->mfc_unres_queue);
1150                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1151
1152                 if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1153                         mod_timer(&mrt->ipmr_expire_timer,
1154                                   c->_c.mfc_un.unres.expires);
1155         }
1156
1157         /* See if we can append the packet */
1158         if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
1159                 kfree_skb(skb);
1160                 err = -ENOBUFS;
1161         } else {
1162                 if (dev) {
1163                         skb->dev = dev;
1164                         skb->skb_iif = dev->ifindex;
1165                 }
1166                 skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
1167                 err = 0;
1168         }
1169
1170         spin_unlock_bh(&mfc_unres_lock);
1171         return err;
1172 }
1173
1174 /* MFC cache manipulation by user space mroute daemon */
1175
1176 static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1177 {
1178         struct net *net = read_pnet(&mrt->net);
1179         struct mfc_cache *c;
1180
1181         /* The entries are added/deleted only under RTNL */
1182         rcu_read_lock();
1183         c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1184                                    mfc->mfcc_mcastgrp.s_addr, parent);
1185         rcu_read_unlock();
1186         if (!c)
1187                 return -ENOENT;
1188         rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ipmr_rht_params);
1189         list_del_rcu(&c->_c.list);
1190         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id);
1191         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1192         mr_cache_put(&c->_c);
1193
1194         return 0;
1195 }
1196
1197 static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1198                         struct mfcctl *mfc, int mrtsock, int parent)
1199 {
1200         struct mfc_cache *uc, *c;
1201         struct mr_mfc *_uc;
1202         bool found;
1203         int ret;
1204
1205         if (mfc->mfcc_parent >= MAXVIFS)
1206                 return -ENFILE;
1207
1208         /* The entries are added/deleted only under RTNL */
1209         rcu_read_lock();
1210         c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1211                                    mfc->mfcc_mcastgrp.s_addr, parent);
1212         rcu_read_unlock();
1213         if (c) {
1214                 spin_lock(&mrt_lock);
1215                 c->_c.mfc_parent = mfc->mfcc_parent;
1216                 ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1217                 if (!mrtsock)
1218                         c->_c.mfc_flags |= MFC_STATIC;
1219                 spin_unlock(&mrt_lock);
1220                 call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c,
1221                                               mrt->id);
1222                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1223                 return 0;
1224         }
1225
1226         if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1227             !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1228                 return -EINVAL;
1229
1230         c = ipmr_cache_alloc();
1231         if (!c)
1232                 return -ENOMEM;
1233
1234         c->mfc_origin = mfc->mfcc_origin.s_addr;
1235         c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1236         c->_c.mfc_parent = mfc->mfcc_parent;
1237         ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1238         if (!mrtsock)
1239                 c->_c.mfc_flags |= MFC_STATIC;
1240
1241         ret = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
1242                                   ipmr_rht_params);
1243         if (ret) {
1244                 pr_err("ipmr: rhtable insert error %d\n", ret);
1245                 ipmr_cache_free(c);
1246                 return ret;
1247         }
1248         list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
1249         /* Check to see if we resolved a queued list. If so we
1250          * need to send on the frames and tidy up.
1251          */
1252         found = false;
1253         spin_lock_bh(&mfc_unres_lock);
1254         list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
1255                 uc = (struct mfc_cache *)_uc;
1256                 if (uc->mfc_origin == c->mfc_origin &&
1257                     uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1258                         list_del(&_uc->list);
1259                         atomic_dec(&mrt->cache_resolve_queue_len);
1260                         found = true;
1261                         break;
1262                 }
1263         }
1264         if (list_empty(&mrt->mfc_unres_queue))
1265                 del_timer(&mrt->ipmr_expire_timer);
1266         spin_unlock_bh(&mfc_unres_lock);
1267
1268         if (found) {
1269                 ipmr_cache_resolve(net, mrt, uc, c);
1270                 ipmr_cache_free(uc);
1271         }
1272         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, c, mrt->id);
1273         mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1274         return 0;
1275 }
1276
1277 /* Close the multicast socket, and clear the vif tables etc */
1278 static void mroute_clean_tables(struct mr_table *mrt, int flags)
1279 {
1280         struct net *net = read_pnet(&mrt->net);
1281         struct mr_mfc *c, *tmp;
1282         struct mfc_cache *cache;
1283         LIST_HEAD(list);
1284         int i;
1285
1286         /* Shut down all active vif entries */
1287         if (flags & (MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC)) {
1288                 for (i = 0; i < mrt->maxvif; i++) {
1289                         if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
1290                              !(flags & MRT_FLUSH_VIFS_STATIC)) ||
1291                             (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT_FLUSH_VIFS)))
1292                                 continue;
1293                         vif_delete(mrt, i, 0, &list);
1294                 }
1295                 unregister_netdevice_many(&list);
1296         }
1297
1298         /* Wipe the cache */
1299         if (flags & (MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC)) {
1300                 list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
1301                         if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC_STATIC)) ||
1302                             (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC)))
1303                                 continue;
1304                         rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
1305                         list_del_rcu(&c->list);
1306                         cache = (struct mfc_cache *)c;
1307                         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
1308                                                       mrt->id);
1309                         mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1310                         mr_cache_put(c);
1311                 }
1312         }
1313
1314         if (flags & MRT_FLUSH_MFC) {
1315                 if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1316                         spin_lock_bh(&mfc_unres_lock);
1317                         list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
1318                                 list_del(&c->list);
1319                                 cache = (struct mfc_cache *)c;
1320                                 mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1321                                 ipmr_destroy_unres(mrt, cache);
1322                         }
1323                         spin_unlock_bh(&mfc_unres_lock);
1324                 }
1325         }
1326 }
1327
1328 /* called from ip_ra_control(), before an RCU grace period,
1329  * we don't need to call synchronize_rcu() here
1330  */
1331 static void mrtsock_destruct(struct sock *sk)
1332 {
1333         struct net *net = sock_net(sk);
1334         struct mr_table *mrt;
1335
1336         rtnl_lock();
1337         ipmr_for_each_table(mrt, net) {
1338                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1339                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1340                         inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1341                                                     NETCONFA_MC_FORWARDING,
1342                                                     NETCONFA_IFINDEX_ALL,
1343                                                     net->ipv4.devconf_all);
1344                         RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1345                         mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_MFC);
1346                 }
1347         }
1348         rtnl_unlock();
1349 }
1350
1351 /* Socket options and virtual interface manipulation. The whole
1352  * virtual interface system is a complete heap, but unfortunately
1353  * that's how BSD mrouted happens to think. Maybe one day with a proper
1354  * MOSPF/PIM router set up we can clean this up.
1355  */
1356
1357 int ip_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval,
1358                          unsigned int optlen)
1359 {
1360         struct net *net = sock_net(sk);
1361         int val, ret = 0, parent = 0;
1362         struct mr_table *mrt;
1363         struct vifctl vif;
1364         struct mfcctl mfc;
1365         bool do_wrvifwhole;
1366         u32 uval;
1367
1368         /* There's one exception to the lock - MRT_DONE which needs to unlock */
1369         rtnl_lock();
1370         if (sk->sk_type != SOCK_RAW ||
1371             inet_sk(sk)->inet_num != IPPROTO_IGMP) {
1372                 ret = -EOPNOTSUPP;
1373                 goto out_unlock;
1374         }
1375
1376         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1377         if (!mrt) {
1378                 ret = -ENOENT;
1379                 goto out_unlock;
1380         }
1381         if (optname != MRT_INIT) {
1382                 if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1383                     !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
1384                         ret = -EACCES;
1385                         goto out_unlock;
1386                 }
1387         }
1388
1389         switch (optname) {
1390         case MRT_INIT:
1391                 if (optlen != sizeof(int)) {
1392                         ret = -EINVAL;
1393                         break;
1394                 }
1395                 if (rtnl_dereference(mrt->mroute_sk)) {
1396                         ret = -EADDRINUSE;
1397                         break;
1398                 }
1399
1400                 ret = ip_ra_control(sk, 1, mrtsock_destruct);
1401                 if (ret == 0) {
1402                         rcu_assign_pointer(mrt->mroute_sk, sk);
1403                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1404                         inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1405                                                     NETCONFA_MC_FORWARDING,
1406                                                     NETCONFA_IFINDEX_ALL,
1407                                                     net->ipv4.devconf_all);
1408                 }
1409                 break;
1410         case MRT_DONE:
1411                 if (sk != rcu_access_pointer(mrt->mroute_sk)) {
1412                         ret = -EACCES;
1413                 } else {
1414                         /* We need to unlock here because mrtsock_destruct takes
1415                          * care of rtnl itself and we can't change that due to
1416                          * the IP_ROUTER_ALERT setsockopt which runs without it.
1417                          */
1418                         rtnl_unlock();
1419                         ret = ip_ra_control(sk, 0, NULL);
1420                         goto out;
1421                 }
1422                 break;
1423         case MRT_ADD_VIF:
1424         case MRT_DEL_VIF:
1425                 if (optlen != sizeof(vif)) {
1426                         ret = -EINVAL;
1427                         break;
1428                 }
1429                 if (copy_from_sockptr(&vif, optval, sizeof(vif))) {
1430                         ret = -EFAULT;
1431                         break;
1432                 }
1433                 if (vif.vifc_vifi >= MAXVIFS) {
1434                         ret = -ENFILE;
1435                         break;
1436                 }
1437                 if (optname == MRT_ADD_VIF) {
1438                         ret = vif_add(net, mrt, &vif,
1439                                       sk == rtnl_dereference(mrt->mroute_sk));
1440                 } else {
1441                         ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1442                 }
1443                 break;
1444         /* Manipulate the forwarding caches. These live
1445          * in a sort of kernel/user symbiosis.
1446          */
1447         case MRT_ADD_MFC:
1448         case MRT_DEL_MFC:
1449                 parent = -1;
1450                 fallthrough;
1451         case MRT_ADD_MFC_PROXY:
1452         case MRT_DEL_MFC_PROXY:
1453                 if (optlen != sizeof(mfc)) {
1454                         ret = -EINVAL;
1455                         break;
1456                 }
1457                 if (copy_from_sockptr(&mfc, optval, sizeof(mfc))) {
1458                         ret = -EFAULT;
1459                         break;
1460                 }
1461                 if (parent == 0)
1462                         parent = mfc.mfcc_parent;
1463                 if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1464                         ret = ipmr_mfc_delete(mrt, &mfc, parent);
1465                 else
1466                         ret = ipmr_mfc_add(net, mrt, &mfc,
1467                                            sk == rtnl_dereference(mrt->mroute_sk),
1468                                            parent);
1469                 break;
1470         case MRT_FLUSH:
1471                 if (optlen != sizeof(val)) {
1472                         ret = -EINVAL;
1473                         break;
1474                 }
1475                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1476                         ret = -EFAULT;
1477                         break;
1478                 }
1479                 mroute_clean_tables(mrt, val);
1480                 break;
1481         /* Control PIM assert. */
1482         case MRT_ASSERT:
1483                 if (optlen != sizeof(val)) {
1484                         ret = -EINVAL;
1485                         break;
1486                 }
1487                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1488                         ret = -EFAULT;
1489                         break;
1490                 }
1491                 mrt->mroute_do_assert = val;
1492                 break;
1493         case MRT_PIM:
1494                 if (!ipmr_pimsm_enabled()) {
1495                         ret = -ENOPROTOOPT;
1496                         break;
1497                 }
1498                 if (optlen != sizeof(val)) {
1499                         ret = -EINVAL;
1500                         break;
1501                 }
1502                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1503                         ret = -EFAULT;
1504                         break;
1505                 }
1506
1507                 do_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE);
1508                 val = !!val;
1509                 if (val != mrt->mroute_do_pim) {
1510                         mrt->mroute_do_pim = val;
1511                         mrt->mroute_do_assert = val;
1512                         mrt->mroute_do_wrvifwhole = do_wrvifwhole;
1513                 }
1514                 break;
1515         case MRT_TABLE:
1516                 if (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) {
1517                         ret = -ENOPROTOOPT;
1518                         break;
1519                 }
1520                 if (optlen != sizeof(uval)) {
1521                         ret = -EINVAL;
1522                         break;
1523                 }
1524                 if (copy_from_sockptr(&uval, optval, sizeof(uval))) {
1525                         ret = -EFAULT;
1526                         break;
1527                 }
1528
1529                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1530                         ret = -EBUSY;
1531                 } else {
1532                         mrt = ipmr_new_table(net, uval);
1533                         if (IS_ERR(mrt))
1534                                 ret = PTR_ERR(mrt);
1535                         else
1536                                 raw_sk(sk)->ipmr_table = uval;
1537                 }
1538                 break;
1539         /* Spurious command, or MRT_VERSION which you cannot set. */
1540         default:
1541                 ret = -ENOPROTOOPT;
1542         }
1543 out_unlock:
1544         rtnl_unlock();
1545 out:
1546         return ret;
1547 }
1548
1549 /* Getsock opt support for the multicast routing system. */
1550 int ip_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval,
1551                          sockptr_t optlen)
1552 {
1553         int olr;
1554         int val;
1555         struct net *net = sock_net(sk);
1556         struct mr_table *mrt;
1557
1558         if (sk->sk_type != SOCK_RAW ||
1559             inet_sk(sk)->inet_num != IPPROTO_IGMP)
1560                 return -EOPNOTSUPP;
1561
1562         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1563         if (!mrt)
1564                 return -ENOENT;
1565
1566         switch (optname) {
1567         case MRT_VERSION:
1568                 val = 0x0305;
1569                 break;
1570         case MRT_PIM:
1571                 if (!ipmr_pimsm_enabled())
1572                         return -ENOPROTOOPT;
1573                 val = mrt->mroute_do_pim;
1574                 break;
1575         case MRT_ASSERT:
1576                 val = mrt->mroute_do_assert;
1577                 break;
1578         default:
1579                 return -ENOPROTOOPT;
1580         }
1581
1582         if (copy_from_sockptr(&olr, optlen, sizeof(int)))
1583                 return -EFAULT;
1584         if (olr < 0)
1585                 return -EINVAL;
1586
1587         olr = min_t(unsigned int, olr, sizeof(int));
1588
1589         if (copy_to_sockptr(optlen, &olr, sizeof(int)))
1590                 return -EFAULT;
1591         if (copy_to_sockptr(optval, &val, olr))
1592                 return -EFAULT;
1593         return 0;
1594 }
1595
1596 /* The IP multicast ioctl support routines. */
1597 int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
1598 {
1599         struct sioc_sg_req sr;
1600         struct sioc_vif_req vr;
1601         struct vif_device *vif;
1602         struct mfc_cache *c;
1603         struct net *net = sock_net(sk);
1604         struct mr_table *mrt;
1605
1606         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1607         if (!mrt)
1608                 return -ENOENT;
1609
1610         switch (cmd) {
1611         case SIOCGETVIFCNT:
1612                 if (copy_from_user(&vr, arg, sizeof(vr)))
1613                         return -EFAULT;
1614                 if (vr.vifi >= mrt->maxvif)
1615                         return -EINVAL;
1616                 vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
1617                 rcu_read_lock();
1618                 vif = &mrt->vif_table[vr.vifi];
1619                 if (VIF_EXISTS(mrt, vr.vifi)) {
1620                         vr.icount = READ_ONCE(vif->pkt_in);
1621                         vr.ocount = READ_ONCE(vif->pkt_out);
1622                         vr.ibytes = READ_ONCE(vif->bytes_in);
1623                         vr.obytes = READ_ONCE(vif->bytes_out);
1624                         rcu_read_unlock();
1625
1626                         if (copy_to_user(arg, &vr, sizeof(vr)))
1627                                 return -EFAULT;
1628                         return 0;
1629                 }
1630                 rcu_read_unlock();
1631                 return -EADDRNOTAVAIL;
1632         case SIOCGETSGCNT:
1633                 if (copy_from_user(&sr, arg, sizeof(sr)))
1634                         return -EFAULT;
1635
1636                 rcu_read_lock();
1637                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1638                 if (c) {
1639                         sr.pktcnt = c->_c.mfc_un.res.pkt;
1640                         sr.bytecnt = c->_c.mfc_un.res.bytes;
1641                         sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1642                         rcu_read_unlock();
1643
1644                         if (copy_to_user(arg, &sr, sizeof(sr)))
1645                                 return -EFAULT;
1646                         return 0;
1647                 }
1648                 rcu_read_unlock();
1649                 return -EADDRNOTAVAIL;
1650         default:
1651                 return -ENOIOCTLCMD;
1652         }
1653 }
1654
1655 #ifdef CONFIG_COMPAT
1656 struct compat_sioc_sg_req {
1657         struct in_addr src;
1658         struct in_addr grp;
1659         compat_ulong_t pktcnt;
1660         compat_ulong_t bytecnt;
1661         compat_ulong_t wrong_if;
1662 };
1663
1664 struct compat_sioc_vif_req {
1665         vifi_t  vifi;           /* Which iface */
1666         compat_ulong_t icount;
1667         compat_ulong_t ocount;
1668         compat_ulong_t ibytes;
1669         compat_ulong_t obytes;
1670 };
1671
1672 int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1673 {
1674         struct compat_sioc_sg_req sr;
1675         struct compat_sioc_vif_req vr;
1676         struct vif_device *vif;
1677         struct mfc_cache *c;
1678         struct net *net = sock_net(sk);
1679         struct mr_table *mrt;
1680
1681         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1682         if (!mrt)
1683                 return -ENOENT;
1684
1685         switch (cmd) {
1686         case SIOCGETVIFCNT:
1687                 if (copy_from_user(&vr, arg, sizeof(vr)))
1688                         return -EFAULT;
1689                 if (vr.vifi >= mrt->maxvif)
1690                         return -EINVAL;
1691                 vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
1692                 rcu_read_lock();
1693                 vif = &mrt->vif_table[vr.vifi];
1694                 if (VIF_EXISTS(mrt, vr.vifi)) {
1695                         vr.icount = READ_ONCE(vif->pkt_in);
1696                         vr.ocount = READ_ONCE(vif->pkt_out);
1697                         vr.ibytes = READ_ONCE(vif->bytes_in);
1698                         vr.obytes = READ_ONCE(vif->bytes_out);
1699                         rcu_read_unlock();
1700
1701                         if (copy_to_user(arg, &vr, sizeof(vr)))
1702                                 return -EFAULT;
1703                         return 0;
1704                 }
1705                 rcu_read_unlock();
1706                 return -EADDRNOTAVAIL;
1707         case SIOCGETSGCNT:
1708                 if (copy_from_user(&sr, arg, sizeof(sr)))
1709                         return -EFAULT;
1710
1711                 rcu_read_lock();
1712                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1713                 if (c) {
1714                         sr.pktcnt = c->_c.mfc_un.res.pkt;
1715                         sr.bytecnt = c->_c.mfc_un.res.bytes;
1716                         sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1717                         rcu_read_unlock();
1718
1719                         if (copy_to_user(arg, &sr, sizeof(sr)))
1720                                 return -EFAULT;
1721                         return 0;
1722                 }
1723                 rcu_read_unlock();
1724                 return -EADDRNOTAVAIL;
1725         default:
1726                 return -ENOIOCTLCMD;
1727         }
1728 }
1729 #endif
1730
1731 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1732 {
1733         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1734         struct net *net = dev_net(dev);
1735         struct mr_table *mrt;
1736         struct vif_device *v;
1737         int ct;
1738
1739         if (event != NETDEV_UNREGISTER)
1740                 return NOTIFY_DONE;
1741
1742         ipmr_for_each_table(mrt, net) {
1743                 v = &mrt->vif_table[0];
1744                 for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1745                         if (rcu_access_pointer(v->dev) == dev)
1746                                 vif_delete(mrt, ct, 1, NULL);
1747                 }
1748         }
1749         return NOTIFY_DONE;
1750 }
1751
1752 static struct notifier_block ip_mr_notifier = {
1753         .notifier_call = ipmr_device_event,
1754 };
1755
1756 /* Encapsulate a packet by attaching a valid IPIP header to it.
1757  * This avoids tunnel drivers and other mess and gives us the speed so
1758  * important for multicast video.
1759  */
1760 static void ip_encap(struct net *net, struct sk_buff *skb,
1761                      __be32 saddr, __be32 daddr)
1762 {
1763         struct iphdr *iph;
1764         const struct iphdr *old_iph = ip_hdr(skb);
1765
1766         skb_push(skb, sizeof(struct iphdr));
1767         skb->transport_header = skb->network_header;
1768         skb_reset_network_header(skb);
1769         iph = ip_hdr(skb);
1770
1771         iph->version    =       4;
1772         iph->tos        =       old_iph->tos;
1773         iph->ttl        =       old_iph->ttl;
1774         iph->frag_off   =       0;
1775         iph->daddr      =       daddr;
1776         iph->saddr      =       saddr;
1777         iph->protocol   =       IPPROTO_IPIP;
1778         iph->ihl        =       5;
1779         iph->tot_len    =       htons(skb->len);
1780         ip_select_ident(net, skb, NULL);
1781         ip_send_check(iph);
1782
1783         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1784         nf_reset_ct(skb);
1785 }
1786
1787 static inline int ipmr_forward_finish(struct net *net, struct sock *sk,
1788                                       struct sk_buff *skb)
1789 {
1790         struct ip_options *opt = &(IPCB(skb)->opt);
1791
1792         IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
1793         IP_ADD_STATS(net, IPSTATS_MIB_OUTOCTETS, skb->len);
1794
1795         if (unlikely(opt->optlen))
1796                 ip_forward_options(skb);
1797
1798         return dst_output(net, sk, skb);
1799 }
1800
1801 #ifdef CONFIG_NET_SWITCHDEV
1802 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1803                                    int in_vifi, int out_vifi)
1804 {
1805         struct vif_device *out_vif = &mrt->vif_table[out_vifi];
1806         struct vif_device *in_vif = &mrt->vif_table[in_vifi];
1807
1808         if (!skb->offload_l3_fwd_mark)
1809                 return false;
1810         if (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
1811                 return false;
1812         return netdev_phys_item_id_same(&out_vif->dev_parent_id,
1813                                         &in_vif->dev_parent_id);
1814 }
1815 #else
1816 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1817                                    int in_vifi, int out_vifi)
1818 {
1819         return false;
1820 }
1821 #endif
1822
1823 /* Processing handlers for ipmr_forward, under rcu_read_lock() */
1824
1825 static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1826                             int in_vifi, struct sk_buff *skb, int vifi)
1827 {
1828         const struct iphdr *iph = ip_hdr(skb);
1829         struct vif_device *vif = &mrt->vif_table[vifi];
1830         struct net_device *vif_dev;
1831         struct net_device *dev;
1832         struct rtable *rt;
1833         struct flowi4 fl4;
1834         int    encap = 0;
1835
1836         vif_dev = vif_dev_read(vif);
1837         if (!vif_dev)
1838                 goto out_free;
1839
1840         if (vif->flags & VIFF_REGISTER) {
1841                 WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1842                 WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1843                 vif_dev->stats.tx_bytes += skb->len;
1844                 vif_dev->stats.tx_packets++;
1845                 ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1846                 goto out_free;
1847         }
1848
1849         if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi))
1850                 goto out_free;
1851
1852         if (vif->flags & VIFF_TUNNEL) {
1853                 rt = ip_route_output_ports(net, &fl4, NULL,
1854                                            vif->remote, vif->local,
1855                                            0, 0,
1856                                            IPPROTO_IPIP,
1857                                            RT_TOS(iph->tos), vif->link);
1858                 if (IS_ERR(rt))
1859                         goto out_free;
1860                 encap = sizeof(struct iphdr);
1861         } else {
1862                 rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1863                                            0, 0,
1864                                            IPPROTO_IPIP,
1865                                            RT_TOS(iph->tos), vif->link);
1866                 if (IS_ERR(rt))
1867                         goto out_free;
1868         }
1869
1870         dev = rt->dst.dev;
1871
1872         if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1873                 /* Do not fragment multicasts. Alas, IPv4 does not
1874                  * allow to send ICMP, so that packets will disappear
1875                  * to blackhole.
1876                  */
1877                 IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
1878                 ip_rt_put(rt);
1879                 goto out_free;
1880         }
1881
1882         encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1883
1884         if (skb_cow(skb, encap)) {
1885                 ip_rt_put(rt);
1886                 goto out_free;
1887         }
1888
1889         WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1890         WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1891
1892         skb_dst_drop(skb);
1893         skb_dst_set(skb, &rt->dst);
1894         ip_decrease_ttl(ip_hdr(skb));
1895
1896         /* FIXME: forward and output firewalls used to be called here.
1897          * What do we do with netfilter? -- RR
1898          */
1899         if (vif->flags & VIFF_TUNNEL) {
1900                 ip_encap(net, skb, vif->local, vif->remote);
1901                 /* FIXME: extra output firewall step used to be here. --RR */
1902                 vif_dev->stats.tx_packets++;
1903                 vif_dev->stats.tx_bytes += skb->len;
1904         }
1905
1906         IPCB(skb)->flags |= IPSKB_FORWARDED;
1907
1908         /* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1909          * not only before forwarding, but after forwarding on all output
1910          * interfaces. It is clear, if mrouter runs a multicasting
1911          * program, it should receive packets not depending to what interface
1912          * program is joined.
1913          * If we will not make it, the program will have to join on all
1914          * interfaces. On the other hand, multihoming host (or router, but
1915          * not mrouter) cannot join to more than one interface - it will
1916          * result in receiving multiple packets.
1917          */
1918         NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
1919                 net, NULL, skb, skb->dev, dev,
1920                 ipmr_forward_finish);
1921         return;
1922
1923 out_free:
1924         kfree_skb(skb);
1925 }
1926
1927 /* Called with mrt_lock or rcu_read_lock() */
1928 static int ipmr_find_vif(const struct mr_table *mrt, struct net_device *dev)
1929 {
1930         int ct;
1931         /* Pairs with WRITE_ONCE() in vif_delete()/vif_add() */
1932         for (ct = READ_ONCE(mrt->maxvif) - 1; ct >= 0; ct--) {
1933                 if (rcu_access_pointer(mrt->vif_table[ct].dev) == dev)
1934                         break;
1935         }
1936         return ct;
1937 }
1938
1939 /* "local" means that we should preserve one skb (for local delivery) */
1940 /* Called uner rcu_read_lock() */
1941 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1942                           struct net_device *dev, struct sk_buff *skb,
1943                           struct mfc_cache *c, int local)
1944 {
1945         int true_vifi = ipmr_find_vif(mrt, dev);
1946         int psend = -1;
1947         int vif, ct;
1948
1949         vif = c->_c.mfc_parent;
1950         c->_c.mfc_un.res.pkt++;
1951         c->_c.mfc_un.res.bytes += skb->len;
1952         c->_c.mfc_un.res.lastuse = jiffies;
1953
1954         if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1955                 struct mfc_cache *cache_proxy;
1956
1957                 /* For an (*,G) entry, we only check that the incoming
1958                  * interface is part of the static tree.
1959                  */
1960                 cache_proxy = mr_mfc_find_any_parent(mrt, vif);
1961                 if (cache_proxy &&
1962                     cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
1963                         goto forward;
1964         }
1965
1966         /* Wrong interface: drop packet and (maybe) send PIM assert. */
1967         if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) {
1968                 if (rt_is_output_route(skb_rtable(skb))) {
1969                         /* It is our own packet, looped back.
1970                          * Very complicated situation...
1971                          *
1972                          * The best workaround until routing daemons will be
1973                          * fixed is not to redistribute packet, if it was
1974                          * send through wrong interface. It means, that
1975                          * multicast applications WILL NOT work for
1976                          * (S,G), which have default multicast route pointing
1977                          * to wrong oif. In any case, it is not a good
1978                          * idea to use multicasting applications on router.
1979                          */
1980                         goto dont_forward;
1981                 }
1982
1983                 c->_c.mfc_un.res.wrong_if++;
1984
1985                 if (true_vifi >= 0 && mrt->mroute_do_assert &&
1986                     /* pimsm uses asserts, when switching from RPT to SPT,
1987                      * so that we cannot check that packet arrived on an oif.
1988                      * It is bad, but otherwise we would need to move pretty
1989                      * large chunk of pimd to kernel. Ough... --ANK
1990                      */
1991                     (mrt->mroute_do_pim ||
1992                      c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
1993                     time_after(jiffies,
1994                                c->_c.mfc_un.res.last_assert +
1995                                MFC_ASSERT_THRESH)) {
1996                         c->_c.mfc_un.res.last_assert = jiffies;
1997                         ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
1998                         if (mrt->mroute_do_wrvifwhole)
1999                                 ipmr_cache_report(mrt, skb, true_vifi,
2000                                                   IGMPMSG_WRVIFWHOLE);
2001                 }
2002                 goto dont_forward;
2003         }
2004
2005 forward:
2006         WRITE_ONCE(mrt->vif_table[vif].pkt_in,
2007                    mrt->vif_table[vif].pkt_in + 1);
2008         WRITE_ONCE(mrt->vif_table[vif].bytes_in,
2009                    mrt->vif_table[vif].bytes_in + skb->len);
2010
2011         /* Forward the frame */
2012         if (c->mfc_origin == htonl(INADDR_ANY) &&
2013             c->mfc_mcastgrp == htonl(INADDR_ANY)) {
2014                 if (true_vifi >= 0 &&
2015                     true_vifi != c->_c.mfc_parent &&
2016                     ip_hdr(skb)->ttl >
2017                                 c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
2018                         /* It's an (*,*) entry and the packet is not coming from
2019                          * the upstream: forward the packet to the upstream
2020                          * only.
2021                          */
2022                         psend = c->_c.mfc_parent;
2023                         goto last_forward;
2024                 }
2025                 goto dont_forward;
2026         }
2027         for (ct = c->_c.mfc_un.res.maxvif - 1;
2028              ct >= c->_c.mfc_un.res.minvif; ct--) {
2029                 /* For (*,G) entry, don't forward to the incoming interface */
2030                 if ((c->mfc_origin != htonl(INADDR_ANY) ||
2031                      ct != true_vifi) &&
2032                     ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) {
2033                         if (psend != -1) {
2034                                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2035
2036                                 if (skb2)
2037                                         ipmr_queue_xmit(net, mrt, true_vifi,
2038                                                         skb2, psend);
2039                         }
2040                         psend = ct;
2041                 }
2042         }
2043 last_forward:
2044         if (psend != -1) {
2045                 if (local) {
2046                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2047
2048                         if (skb2)
2049                                 ipmr_queue_xmit(net, mrt, true_vifi, skb2,
2050                                                 psend);
2051                 } else {
2052                         ipmr_queue_xmit(net, mrt, true_vifi, skb, psend);
2053                         return;
2054                 }
2055         }
2056
2057 dont_forward:
2058         if (!local)
2059                 kfree_skb(skb);
2060 }
2061
2062 static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
2063 {
2064         struct rtable *rt = skb_rtable(skb);
2065         struct iphdr *iph = ip_hdr(skb);
2066         struct flowi4 fl4 = {
2067                 .daddr = iph->daddr,
2068                 .saddr = iph->saddr,
2069                 .flowi4_tos = RT_TOS(iph->tos),
2070                 .flowi4_oif = (rt_is_output_route(rt) ?
2071                                skb->dev->ifindex : 0),
2072                 .flowi4_iif = (rt_is_output_route(rt) ?
2073                                LOOPBACK_IFINDEX :
2074                                skb->dev->ifindex),
2075                 .flowi4_mark = skb->mark,
2076         };
2077         struct mr_table *mrt;
2078         int err;
2079
2080         err = ipmr_fib_lookup(net, &fl4, &mrt);
2081         if (err)
2082                 return ERR_PTR(err);
2083         return mrt;
2084 }
2085
2086 /* Multicast packets for forwarding arrive here
2087  * Called with rcu_read_lock();
2088  */
2089 int ip_mr_input(struct sk_buff *skb)
2090 {
2091         struct mfc_cache *cache;
2092         struct net *net = dev_net(skb->dev);
2093         int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
2094         struct mr_table *mrt;
2095         struct net_device *dev;
2096
2097         /* skb->dev passed in is the loX master dev for vrfs.
2098          * As there are no vifs associated with loopback devices,
2099          * get the proper interface that does have a vif associated with it.
2100          */
2101         dev = skb->dev;
2102         if (netif_is_l3_master(skb->dev)) {
2103                 dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
2104                 if (!dev) {
2105                         kfree_skb(skb);
2106                         return -ENODEV;
2107                 }
2108         }
2109
2110         /* Packet is looped back after forward, it should not be
2111          * forwarded second time, but still can be delivered locally.
2112          */
2113         if (IPCB(skb)->flags & IPSKB_FORWARDED)
2114                 goto dont_forward;
2115
2116         mrt = ipmr_rt_fib_lookup(net, skb);
2117         if (IS_ERR(mrt)) {
2118                 kfree_skb(skb);
2119                 return PTR_ERR(mrt);
2120         }
2121         if (!local) {
2122                 if (IPCB(skb)->opt.router_alert) {
2123                         if (ip_call_ra_chain(skb))
2124                                 return 0;
2125                 } else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
2126                         /* IGMPv1 (and broken IGMPv2 implementations sort of
2127                          * Cisco IOS <= 11.2(8)) do not put router alert
2128                          * option to IGMP packets destined to routable
2129                          * groups. It is very bad, because it means
2130                          * that we can forward NO IGMP messages.
2131                          */
2132                         struct sock *mroute_sk;
2133
2134                         mroute_sk = rcu_dereference(mrt->mroute_sk);
2135                         if (mroute_sk) {
2136                                 nf_reset_ct(skb);
2137                                 raw_rcv(mroute_sk, skb);
2138                                 return 0;
2139                         }
2140                 }
2141         }
2142
2143         /* already under rcu_read_lock() */
2144         cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
2145         if (!cache) {
2146                 int vif = ipmr_find_vif(mrt, dev);
2147
2148                 if (vif >= 0)
2149                         cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
2150                                                     vif);
2151         }
2152
2153         /* No usable cache entry */
2154         if (!cache) {
2155                 int vif;
2156
2157                 if (local) {
2158                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2159                         ip_local_deliver(skb);
2160                         if (!skb2)
2161                                 return -ENOBUFS;
2162                         skb = skb2;
2163                 }
2164
2165                 vif = ipmr_find_vif(mrt, dev);
2166                 if (vif >= 0)
2167                         return ipmr_cache_unresolved(mrt, vif, skb, dev);
2168                 kfree_skb(skb);
2169                 return -ENODEV;
2170         }
2171
2172         ip_mr_forward(net, mrt, dev, skb, cache, local);
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                 if (dev)
2270                         vif = ipmr_find_vif(mrt, dev);
2271                 if (vif < 0) {
2272                         rcu_read_unlock();
2273                         return -ENODEV;
2274                 }
2275
2276                 skb2 = skb_realloc_headroom(skb, sizeof(struct iphdr));
2277                 if (!skb2) {
2278                         rcu_read_unlock();
2279                         return -ENOMEM;
2280                 }
2281
2282                 NETLINK_CB(skb2).portid = portid;
2283                 skb_push(skb2, sizeof(struct iphdr));
2284                 skb_reset_network_header(skb2);
2285                 iph = ip_hdr(skb2);
2286                 iph->ihl = sizeof(struct iphdr) >> 2;
2287                 iph->saddr = saddr;
2288                 iph->daddr = daddr;
2289                 iph->version = 0;
2290                 err = ipmr_cache_unresolved(mrt, vif, skb2, dev);
2291                 rcu_read_unlock();
2292                 return err;
2293         }
2294
2295         err = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
2296         rcu_read_unlock();
2297         return err;
2298 }
2299
2300 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2301                             u32 portid, u32 seq, struct mfc_cache *c, int cmd,
2302                             int flags)
2303 {
2304         struct nlmsghdr *nlh;
2305         struct rtmsg *rtm;
2306         int err;
2307
2308         nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2309         if (!nlh)
2310                 return -EMSGSIZE;
2311
2312         rtm = nlmsg_data(nlh);
2313         rtm->rtm_family   = RTNL_FAMILY_IPMR;
2314         rtm->rtm_dst_len  = 32;
2315         rtm->rtm_src_len  = 32;
2316         rtm->rtm_tos      = 0;
2317         rtm->rtm_table    = mrt->id;
2318         if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2319                 goto nla_put_failure;
2320         rtm->rtm_type     = RTN_MULTICAST;
2321         rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2322         if (c->_c.mfc_flags & MFC_STATIC)
2323                 rtm->rtm_protocol = RTPROT_STATIC;
2324         else
2325                 rtm->rtm_protocol = RTPROT_MROUTED;
2326         rtm->rtm_flags    = 0;
2327
2328         if (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) ||
2329             nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp))
2330                 goto nla_put_failure;
2331         err = mr_fill_mroute(mrt, skb, &c->_c, rtm);
2332         /* do not break the dump if cache is unresolved */
2333         if (err < 0 && err != -ENOENT)
2334                 goto nla_put_failure;
2335
2336         nlmsg_end(skb, nlh);
2337         return 0;
2338
2339 nla_put_failure:
2340         nlmsg_cancel(skb, nlh);
2341         return -EMSGSIZE;
2342 }
2343
2344 static int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2345                              u32 portid, u32 seq, struct mr_mfc *c, int cmd,
2346                              int flags)
2347 {
2348         return ipmr_fill_mroute(mrt, skb, portid, seq, (struct mfc_cache *)c,
2349                                 cmd, flags);
2350 }
2351
2352 static size_t mroute_msgsize(bool unresolved, int maxvif)
2353 {
2354         size_t len =
2355                 NLMSG_ALIGN(sizeof(struct rtmsg))
2356                 + nla_total_size(4)     /* RTA_TABLE */
2357                 + nla_total_size(4)     /* RTA_SRC */
2358                 + nla_total_size(4)     /* RTA_DST */
2359                 ;
2360
2361         if (!unresolved)
2362                 len = len
2363                       + nla_total_size(4)       /* RTA_IIF */
2364                       + nla_total_size(0)       /* RTA_MULTIPATH */
2365                       + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2366                                                 /* RTA_MFC_STATS */
2367                       + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
2368                 ;
2369
2370         return len;
2371 }
2372
2373 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2374                                  int cmd)
2375 {
2376         struct net *net = read_pnet(&mrt->net);
2377         struct sk_buff *skb;
2378         int err = -ENOBUFS;
2379
2380         skb = nlmsg_new(mroute_msgsize(mfc->_c.mfc_parent >= MAXVIFS,
2381                                        mrt->maxvif),
2382                         GFP_ATOMIC);
2383         if (!skb)
2384                 goto errout;
2385
2386         err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2387         if (err < 0)
2388                 goto errout;
2389
2390         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2391         return;
2392
2393 errout:
2394         kfree_skb(skb);
2395         if (err < 0)
2396                 rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
2397 }
2398
2399 static size_t igmpmsg_netlink_msgsize(size_t payloadlen)
2400 {
2401         size_t len =
2402                 NLMSG_ALIGN(sizeof(struct rtgenmsg))
2403                 + nla_total_size(1)     /* IPMRA_CREPORT_MSGTYPE */
2404                 + nla_total_size(4)     /* IPMRA_CREPORT_VIF_ID */
2405                 + nla_total_size(4)     /* IPMRA_CREPORT_SRC_ADDR */
2406                 + nla_total_size(4)     /* IPMRA_CREPORT_DST_ADDR */
2407                 + nla_total_size(4)     /* IPMRA_CREPORT_TABLE */
2408                                         /* IPMRA_CREPORT_PKT */
2409                 + nla_total_size(payloadlen)
2410                 ;
2411
2412         return len;
2413 }
2414
2415 static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt)
2416 {
2417         struct net *net = read_pnet(&mrt->net);
2418         struct nlmsghdr *nlh;
2419         struct rtgenmsg *rtgenm;
2420         struct igmpmsg *msg;
2421         struct sk_buff *skb;
2422         struct nlattr *nla;
2423         int payloadlen;
2424
2425         payloadlen = pkt->len - sizeof(struct igmpmsg);
2426         msg = (struct igmpmsg *)skb_network_header(pkt);
2427
2428         skb = nlmsg_new(igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2429         if (!skb)
2430                 goto errout;
2431
2432         nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
2433                         sizeof(struct rtgenmsg), 0);
2434         if (!nlh)
2435                 goto errout;
2436         rtgenm = nlmsg_data(nlh);
2437         rtgenm->rtgen_family = RTNL_FAMILY_IPMR;
2438         if (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) ||
2439             nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif | (msg->im_vif_hi << 8)) ||
2440             nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR,
2441                             msg->im_src.s_addr) ||
2442             nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR,
2443                             msg->im_dst.s_addr) ||
2444             nla_put_u32(skb, IPMRA_CREPORT_TABLE, mrt->id))
2445                 goto nla_put_failure;
2446
2447         nla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen);
2448         if (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg),
2449                                   nla_data(nla), payloadlen))
2450                 goto nla_put_failure;
2451
2452         nlmsg_end(skb, nlh);
2453
2454         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
2455         return;
2456
2457 nla_put_failure:
2458         nlmsg_cancel(skb, nlh);
2459 errout:
2460         kfree_skb(skb);
2461         rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS);
2462 }
2463
2464 static int ipmr_rtm_valid_getroute_req(struct sk_buff *skb,
2465                                        const struct nlmsghdr *nlh,
2466                                        struct nlattr **tb,
2467                                        struct netlink_ext_ack *extack)
2468 {
2469         struct rtmsg *rtm;
2470         int i, err;
2471
2472         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2473                 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for multicast route get request");
2474                 return -EINVAL;
2475         }
2476
2477         if (!netlink_strict_get_check(skb))
2478                 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
2479                                               rtm_ipv4_policy, extack);
2480
2481         rtm = nlmsg_data(nlh);
2482         if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) ||
2483             (rtm->rtm_dst_len && rtm->rtm_dst_len != 32) ||
2484             rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol ||
2485             rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) {
2486                 NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for multicast route get request");
2487                 return -EINVAL;
2488         }
2489
2490         err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2491                                             rtm_ipv4_policy, extack);
2492         if (err)
2493                 return err;
2494
2495         if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
2496             (tb[RTA_DST] && !rtm->rtm_dst_len)) {
2497                 NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4");
2498                 return -EINVAL;
2499         }
2500
2501         for (i = 0; i <= RTA_MAX; i++) {
2502                 if (!tb[i])
2503                         continue;
2504
2505                 switch (i) {
2506                 case RTA_SRC:
2507                 case RTA_DST:
2508                 case RTA_TABLE:
2509                         break;
2510                 default:
2511                         NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in multicast route get request");
2512                         return -EINVAL;
2513                 }
2514         }
2515
2516         return 0;
2517 }
2518
2519 static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2520                              struct netlink_ext_ack *extack)
2521 {
2522         struct net *net = sock_net(in_skb->sk);
2523         struct nlattr *tb[RTA_MAX + 1];
2524         struct sk_buff *skb = NULL;
2525         struct mfc_cache *cache;
2526         struct mr_table *mrt;
2527         __be32 src, grp;
2528         u32 tableid;
2529         int err;
2530
2531         err = ipmr_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
2532         if (err < 0)
2533                 goto errout;
2534
2535         src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
2536         grp = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
2537         tableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0;
2538
2539         mrt = ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT);
2540         if (!mrt) {
2541                 err = -ENOENT;
2542                 goto errout_free;
2543         }
2544
2545         /* entries are added/deleted only under RTNL */
2546         rcu_read_lock();
2547         cache = ipmr_cache_find(mrt, src, grp);
2548         rcu_read_unlock();
2549         if (!cache) {
2550                 err = -ENOENT;
2551                 goto errout_free;
2552         }
2553
2554         skb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL);
2555         if (!skb) {
2556                 err = -ENOBUFS;
2557                 goto errout_free;
2558         }
2559
2560         err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
2561                                nlh->nlmsg_seq, cache,
2562                                RTM_NEWROUTE, 0);
2563         if (err < 0)
2564                 goto errout_free;
2565
2566         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2567
2568 errout:
2569         return err;
2570
2571 errout_free:
2572         kfree_skb(skb);
2573         goto errout;
2574 }
2575
2576 static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2577 {
2578         struct fib_dump_filter filter = {};
2579         int err;
2580
2581         if (cb->strict_check) {
2582                 err = ip_valid_fib_dump_req(sock_net(skb->sk), cb->nlh,
2583                                             &filter, cb);
2584                 if (err < 0)
2585                         return err;
2586         }
2587
2588         if (filter.table_id) {
2589                 struct mr_table *mrt;
2590
2591                 mrt = ipmr_get_table(sock_net(skb->sk), filter.table_id);
2592                 if (!mrt) {
2593                         if (rtnl_msg_family(cb->nlh) != RTNL_FAMILY_IPMR)
2594                                 return skb->len;
2595
2596                         NL_SET_ERR_MSG(cb->extack, "ipv4: MR table does not exist");
2597                         return -ENOENT;
2598                 }
2599                 err = mr_table_dump(mrt, skb, cb, _ipmr_fill_mroute,
2600                                     &mfc_unres_lock, &filter);
2601                 return skb->len ? : err;
2602         }
2603
2604         return mr_rtm_dumproute(skb, cb, ipmr_mr_table_iter,
2605                                 _ipmr_fill_mroute, &mfc_unres_lock, &filter);
2606 }
2607
2608 static const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = {
2609         [RTA_SRC]       = { .type = NLA_U32 },
2610         [RTA_DST]       = { .type = NLA_U32 },
2611         [RTA_IIF]       = { .type = NLA_U32 },
2612         [RTA_TABLE]     = { .type = NLA_U32 },
2613         [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
2614 };
2615
2616 static bool ipmr_rtm_validate_proto(unsigned char rtm_protocol)
2617 {
2618         switch (rtm_protocol) {
2619         case RTPROT_STATIC:
2620         case RTPROT_MROUTED:
2621                 return true;
2622         }
2623         return false;
2624 }
2625
2626 static int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc)
2627 {
2628         struct rtnexthop *rtnh = nla_data(nla);
2629         int remaining = nla_len(nla), vifi = 0;
2630
2631         while (rtnh_ok(rtnh, remaining)) {
2632                 mfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops;
2633                 if (++vifi == MAXVIFS)
2634                         break;
2635                 rtnh = rtnh_next(rtnh, &remaining);
2636         }
2637
2638         return remaining > 0 ? -EINVAL : vifi;
2639 }
2640
2641 /* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY */
2642 static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh,
2643                             struct mfcctl *mfcc, int *mrtsock,
2644                             struct mr_table **mrtret,
2645                             struct netlink_ext_ack *extack)
2646 {
2647         struct net_device *dev = NULL;
2648         u32 tblid = RT_TABLE_DEFAULT;
2649         struct mr_table *mrt;
2650         struct nlattr *attr;
2651         struct rtmsg *rtm;
2652         int ret, rem;
2653
2654         ret = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX,
2655                                         rtm_ipmr_policy, extack);
2656         if (ret < 0)
2657                 goto out;
2658         rtm = nlmsg_data(nlh);
2659
2660         ret = -EINVAL;
2661         if (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 ||
2662             rtm->rtm_type != RTN_MULTICAST ||
2663             rtm->rtm_scope != RT_SCOPE_UNIVERSE ||
2664             !ipmr_rtm_validate_proto(rtm->rtm_protocol))
2665                 goto out;
2666
2667         memset(mfcc, 0, sizeof(*mfcc));
2668         mfcc->mfcc_parent = -1;
2669         ret = 0;
2670         nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) {
2671                 switch (nla_type(attr)) {
2672                 case RTA_SRC:
2673                         mfcc->mfcc_origin.s_addr = nla_get_be32(attr);
2674                         break;
2675                 case RTA_DST:
2676                         mfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr);
2677                         break;
2678                 case RTA_IIF:
2679                         dev = __dev_get_by_index(net, nla_get_u32(attr));
2680                         if (!dev) {
2681                                 ret = -ENODEV;
2682                                 goto out;
2683                         }
2684                         break;
2685                 case RTA_MULTIPATH:
2686                         if (ipmr_nla_get_ttls(attr, mfcc) < 0) {
2687                                 ret = -EINVAL;
2688                                 goto out;
2689                         }
2690                         break;
2691                 case RTA_PREFSRC:
2692                         ret = 1;
2693                         break;
2694                 case RTA_TABLE:
2695                         tblid = nla_get_u32(attr);
2696                         break;
2697                 }
2698         }
2699         mrt = ipmr_get_table(net, tblid);
2700         if (!mrt) {
2701                 ret = -ENOENT;
2702                 goto out;
2703         }
2704         *mrtret = mrt;
2705         *mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0;
2706         if (dev)
2707                 mfcc->mfcc_parent = ipmr_find_vif(mrt, dev);
2708
2709 out:
2710         return ret;
2711 }
2712
2713 /* takes care of both newroute and delroute */
2714 static int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh,
2715                           struct netlink_ext_ack *extack)
2716 {
2717         struct net *net = sock_net(skb->sk);
2718         int ret, mrtsock, parent;
2719         struct mr_table *tbl;
2720         struct mfcctl mfcc;
2721
2722         mrtsock = 0;
2723         tbl = NULL;
2724         ret = rtm_to_ipmr_mfcc(net, nlh, &mfcc, &mrtsock, &tbl, extack);
2725         if (ret < 0)
2726                 return ret;
2727
2728         parent = ret ? mfcc.mfcc_parent : -1;
2729         if (nlh->nlmsg_type == RTM_NEWROUTE)
2730                 return ipmr_mfc_add(net, tbl, &mfcc, mrtsock, parent);
2731         else
2732                 return ipmr_mfc_delete(tbl, &mfcc, parent);
2733 }
2734
2735 static bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb)
2736 {
2737         u32 queue_len = atomic_read(&mrt->cache_resolve_queue_len);
2738
2739         if (nla_put_u32(skb, IPMRA_TABLE_ID, mrt->id) ||
2740             nla_put_u32(skb, IPMRA_TABLE_CACHE_RES_QUEUE_LEN, queue_len) ||
2741             nla_put_s32(skb, IPMRA_TABLE_MROUTE_REG_VIF_NUM,
2742                         mrt->mroute_reg_vif_num) ||
2743             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_ASSERT,
2744                        mrt->mroute_do_assert) ||
2745             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_PIM, mrt->mroute_do_pim) ||
2746             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE,
2747                        mrt->mroute_do_wrvifwhole))
2748                 return false;
2749
2750         return true;
2751 }
2752
2753 static bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb)
2754 {
2755         struct net_device *vif_dev;
2756         struct nlattr *vif_nest;
2757         struct vif_device *vif;
2758
2759         vif = &mrt->vif_table[vifid];
2760         vif_dev = rtnl_dereference(vif->dev);
2761         /* if the VIF doesn't exist just continue */
2762         if (!vif_dev)
2763                 return true;
2764
2765         vif_nest = nla_nest_start_noflag(skb, IPMRA_VIF);
2766         if (!vif_nest)
2767                 return false;
2768
2769         if (nla_put_u32(skb, IPMRA_VIFA_IFINDEX, vif_dev->ifindex) ||
2770             nla_put_u32(skb, IPMRA_VIFA_VIF_ID, vifid) ||
2771             nla_put_u16(skb, IPMRA_VIFA_FLAGS, vif->flags) ||
2772             nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_IN, vif->bytes_in,
2773                               IPMRA_VIFA_PAD) ||
2774             nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_OUT, vif->bytes_out,
2775                               IPMRA_VIFA_PAD) ||
2776             nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_IN, vif->pkt_in,
2777                               IPMRA_VIFA_PAD) ||
2778             nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_OUT, vif->pkt_out,
2779                               IPMRA_VIFA_PAD) ||
2780             nla_put_be32(skb, IPMRA_VIFA_LOCAL_ADDR, vif->local) ||
2781             nla_put_be32(skb, IPMRA_VIFA_REMOTE_ADDR, vif->remote)) {
2782                 nla_nest_cancel(skb, vif_nest);
2783                 return false;
2784         }
2785         nla_nest_end(skb, vif_nest);
2786
2787         return true;
2788 }
2789
2790 static int ipmr_valid_dumplink(const struct nlmsghdr *nlh,
2791                                struct netlink_ext_ack *extack)
2792 {
2793         struct ifinfomsg *ifm;
2794
2795         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
2796                 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for ipmr link dump");
2797                 return -EINVAL;
2798         }
2799
2800         if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
2801                 NL_SET_ERR_MSG(extack, "Invalid data after header in ipmr link dump");
2802                 return -EINVAL;
2803         }
2804
2805         ifm = nlmsg_data(nlh);
2806         if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
2807             ifm->ifi_change || ifm->ifi_index) {
2808                 NL_SET_ERR_MSG(extack, "Invalid values in header for ipmr link dump request");
2809                 return -EINVAL;
2810         }
2811
2812         return 0;
2813 }
2814
2815 static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb)
2816 {
2817         struct net *net = sock_net(skb->sk);
2818         struct nlmsghdr *nlh = NULL;
2819         unsigned int t = 0, s_t;
2820         unsigned int e = 0, s_e;
2821         struct mr_table *mrt;
2822
2823         if (cb->strict_check) {
2824                 int err = ipmr_valid_dumplink(cb->nlh, cb->extack);
2825
2826                 if (err < 0)
2827                         return err;
2828         }
2829
2830         s_t = cb->args[0];
2831         s_e = cb->args[1];
2832
2833         ipmr_for_each_table(mrt, net) {
2834                 struct nlattr *vifs, *af;
2835                 struct ifinfomsg *hdr;
2836                 u32 i;
2837
2838                 if (t < s_t)
2839                         goto skip_table;
2840                 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
2841                                 cb->nlh->nlmsg_seq, RTM_NEWLINK,
2842                                 sizeof(*hdr), NLM_F_MULTI);
2843                 if (!nlh)
2844                         break;
2845
2846                 hdr = nlmsg_data(nlh);
2847                 memset(hdr, 0, sizeof(*hdr));
2848                 hdr->ifi_family = RTNL_FAMILY_IPMR;
2849
2850                 af = nla_nest_start_noflag(skb, IFLA_AF_SPEC);
2851                 if (!af) {
2852                         nlmsg_cancel(skb, nlh);
2853                         goto out;
2854                 }
2855
2856                 if (!ipmr_fill_table(mrt, skb)) {
2857                         nlmsg_cancel(skb, nlh);
2858                         goto out;
2859                 }
2860
2861                 vifs = nla_nest_start_noflag(skb, IPMRA_TABLE_VIFS);
2862                 if (!vifs) {
2863                         nla_nest_end(skb, af);
2864                         nlmsg_end(skb, nlh);
2865                         goto out;
2866                 }
2867                 for (i = 0; i < mrt->maxvif; i++) {
2868                         if (e < s_e)
2869                                 goto skip_entry;
2870                         if (!ipmr_fill_vif(mrt, i, skb)) {
2871                                 nla_nest_end(skb, vifs);
2872                                 nla_nest_end(skb, af);
2873                                 nlmsg_end(skb, nlh);
2874                                 goto out;
2875                         }
2876 skip_entry:
2877                         e++;
2878                 }
2879                 s_e = 0;
2880                 e = 0;
2881                 nla_nest_end(skb, vifs);
2882                 nla_nest_end(skb, af);
2883                 nlmsg_end(skb, nlh);
2884 skip_table:
2885                 t++;
2886         }
2887
2888 out:
2889         cb->args[1] = e;
2890         cb->args[0] = t;
2891
2892         return skb->len;
2893 }
2894
2895 #ifdef CONFIG_PROC_FS
2896 /* The /proc interfaces to multicast routing :
2897  * /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2898  */
2899
2900 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2901         __acquires(RCU)
2902 {
2903         struct mr_vif_iter *iter = seq->private;
2904         struct net *net = seq_file_net(seq);
2905         struct mr_table *mrt;
2906
2907         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2908         if (!mrt)
2909                 return ERR_PTR(-ENOENT);
2910
2911         iter->mrt = mrt;
2912
2913         rcu_read_lock();
2914         return mr_vif_seq_start(seq, pos);
2915 }
2916
2917 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2918         __releases(RCU)
2919 {
2920         rcu_read_unlock();
2921 }
2922
2923 static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2924 {
2925         struct mr_vif_iter *iter = seq->private;
2926         struct mr_table *mrt = iter->mrt;
2927
2928         if (v == SEQ_START_TOKEN) {
2929                 seq_puts(seq,
2930                          "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
2931         } else {
2932                 const struct vif_device *vif = v;
2933                 const struct net_device *vif_dev;
2934                 const char *name;
2935
2936                 vif_dev = vif_dev_read(vif);
2937                 name = vif_dev ? vif_dev->name : "none";
2938                 seq_printf(seq,
2939                            "%2td %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
2940                            vif - mrt->vif_table,
2941                            name, vif->bytes_in, vif->pkt_in,
2942                            vif->bytes_out, vif->pkt_out,
2943                            vif->flags, vif->local, vif->remote);
2944         }
2945         return 0;
2946 }
2947
2948 static const struct seq_operations ipmr_vif_seq_ops = {
2949         .start = ipmr_vif_seq_start,
2950         .next  = mr_vif_seq_next,
2951         .stop  = ipmr_vif_seq_stop,
2952         .show  = ipmr_vif_seq_show,
2953 };
2954
2955 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2956 {
2957         struct net *net = seq_file_net(seq);
2958         struct mr_table *mrt;
2959
2960         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2961         if (!mrt)
2962                 return ERR_PTR(-ENOENT);
2963
2964         return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
2965 }
2966
2967 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2968 {
2969         int n;
2970
2971         if (v == SEQ_START_TOKEN) {
2972                 seq_puts(seq,
2973                  "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
2974         } else {
2975                 const struct mfc_cache *mfc = v;
2976                 const struct mr_mfc_iter *it = seq->private;
2977                 const struct mr_table *mrt = it->mrt;
2978
2979                 seq_printf(seq, "%08X %08X %-3hd",
2980                            (__force u32) mfc->mfc_mcastgrp,
2981                            (__force u32) mfc->mfc_origin,
2982                            mfc->_c.mfc_parent);
2983
2984                 if (it->cache != &mrt->mfc_unres_queue) {
2985                         seq_printf(seq, " %8lu %8lu %8lu",
2986                                    mfc->_c.mfc_un.res.pkt,
2987                                    mfc->_c.mfc_un.res.bytes,
2988                                    mfc->_c.mfc_un.res.wrong_if);
2989                         for (n = mfc->_c.mfc_un.res.minvif;
2990                              n < mfc->_c.mfc_un.res.maxvif; n++) {
2991                                 if (VIF_EXISTS(mrt, n) &&
2992                                     mfc->_c.mfc_un.res.ttls[n] < 255)
2993                                         seq_printf(seq,
2994                                            " %2d:%-3d",
2995                                            n, mfc->_c.mfc_un.res.ttls[n]);
2996                         }
2997                 } else {
2998                         /* unresolved mfc_caches don't contain
2999                          * pkt, bytes and wrong_if values
3000                          */
3001                         seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
3002                 }
3003                 seq_putc(seq, '\n');
3004         }
3005         return 0;
3006 }
3007
3008 static const struct seq_operations ipmr_mfc_seq_ops = {
3009         .start = ipmr_mfc_seq_start,
3010         .next  = mr_mfc_seq_next,
3011         .stop  = mr_mfc_seq_stop,
3012         .show  = ipmr_mfc_seq_show,
3013 };
3014 #endif
3015
3016 #ifdef CONFIG_IP_PIMSM_V2
3017 static const struct net_protocol pim_protocol = {
3018         .handler        =       pim_rcv,
3019 };
3020 #endif
3021
3022 static unsigned int ipmr_seq_read(struct net *net)
3023 {
3024         ASSERT_RTNL();
3025
3026         return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
3027 }
3028
3029 static int ipmr_dump(struct net *net, struct notifier_block *nb,
3030                      struct netlink_ext_ack *extack)
3031 {
3032         return mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump,
3033                        ipmr_mr_table_iter, extack);
3034 }
3035
3036 static const struct fib_notifier_ops ipmr_notifier_ops_template = {
3037         .family         = RTNL_FAMILY_IPMR,
3038         .fib_seq_read   = ipmr_seq_read,
3039         .fib_dump       = ipmr_dump,
3040         .owner          = THIS_MODULE,
3041 };
3042
3043 static int __net_init ipmr_notifier_init(struct net *net)
3044 {
3045         struct fib_notifier_ops *ops;
3046
3047         net->ipv4.ipmr_seq = 0;
3048
3049         ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net);
3050         if (IS_ERR(ops))
3051                 return PTR_ERR(ops);
3052         net->ipv4.ipmr_notifier_ops = ops;
3053
3054         return 0;
3055 }
3056
3057 static void __net_exit ipmr_notifier_exit(struct net *net)
3058 {
3059         fib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops);
3060         net->ipv4.ipmr_notifier_ops = NULL;
3061 }
3062
3063 /* Setup for IP multicast routing */
3064 static int __net_init ipmr_net_init(struct net *net)
3065 {
3066         int err;
3067
3068         err = ipmr_notifier_init(net);
3069         if (err)
3070                 goto ipmr_notifier_fail;
3071
3072         err = ipmr_rules_init(net);
3073         if (err < 0)
3074                 goto ipmr_rules_fail;
3075
3076 #ifdef CONFIG_PROC_FS
3077         err = -ENOMEM;
3078         if (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops,
3079                         sizeof(struct mr_vif_iter)))
3080                 goto proc_vif_fail;
3081         if (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
3082                         sizeof(struct mr_mfc_iter)))
3083                 goto proc_cache_fail;
3084 #endif
3085         return 0;
3086
3087 #ifdef CONFIG_PROC_FS
3088 proc_cache_fail:
3089         remove_proc_entry("ip_mr_vif", net->proc_net);
3090 proc_vif_fail:
3091         rtnl_lock();
3092         ipmr_rules_exit(net);
3093         rtnl_unlock();
3094 #endif
3095 ipmr_rules_fail:
3096         ipmr_notifier_exit(net);
3097 ipmr_notifier_fail:
3098         return err;
3099 }
3100
3101 static void __net_exit ipmr_net_exit(struct net *net)
3102 {
3103 #ifdef CONFIG_PROC_FS
3104         remove_proc_entry("ip_mr_cache", net->proc_net);
3105         remove_proc_entry("ip_mr_vif", net->proc_net);
3106 #endif
3107         ipmr_notifier_exit(net);
3108 }
3109
3110 static void __net_exit ipmr_net_exit_batch(struct list_head *net_list)
3111 {
3112         struct net *net;
3113
3114         rtnl_lock();
3115         list_for_each_entry(net, net_list, exit_list)
3116                 ipmr_rules_exit(net);
3117         rtnl_unlock();
3118 }
3119
3120 static struct pernet_operations ipmr_net_ops = {
3121         .init = ipmr_net_init,
3122         .exit = ipmr_net_exit,
3123         .exit_batch = ipmr_net_exit_batch,
3124 };
3125
3126 int __init ip_mr_init(void)
3127 {
3128         int err;
3129
3130         mrt_cachep = kmem_cache_create("ip_mrt_cache",
3131                                        sizeof(struct mfc_cache),
3132                                        0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
3133                                        NULL);
3134
3135         err = register_pernet_subsys(&ipmr_net_ops);
3136         if (err)
3137                 goto reg_pernet_fail;
3138
3139         err = register_netdevice_notifier(&ip_mr_notifier);
3140         if (err)
3141                 goto reg_notif_fail;
3142 #ifdef CONFIG_IP_PIMSM_V2
3143         if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
3144                 pr_err("%s: can't add PIM protocol\n", __func__);
3145                 err = -EAGAIN;
3146                 goto add_proto_fail;
3147         }
3148 #endif
3149         rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
3150                       ipmr_rtm_getroute, ipmr_rtm_dumproute, 0);
3151         rtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE,
3152                       ipmr_rtm_route, NULL, 0);
3153         rtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE,
3154                       ipmr_rtm_route, NULL, 0);
3155
3156         rtnl_register(RTNL_FAMILY_IPMR, RTM_GETLINK,
3157                       NULL, ipmr_rtm_dumplink, 0);
3158         return 0;
3159
3160 #ifdef CONFIG_IP_PIMSM_V2
3161 add_proto_fail:
3162         unregister_netdevice_notifier(&ip_mr_notifier);
3163 #endif
3164 reg_notif_fail:
3165         unregister_pernet_subsys(&ipmr_net_ops);
3166 reg_pernet_fail:
3167         kmem_cache_destroy(mrt_cachep);
3168         return err;
3169 }