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         timer_shutdown_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_ADD(dev, tx_bytes, skb->len);
 510         DEV_STATS_INC(dev, 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         if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE)
1029                 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
1030         else
1031                 skb = alloc_skb(128, GFP_ATOMIC);
1032
1033         if (!skb)
1034                 return -ENOBUFS;
1035
1036         if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) {
1037                 /* Ugly, but we have no choice with this interface.
1038                  * Duplicate old header, fix ihl, length etc.
1039                  * And all this only to mangle msg->im_msgtype and
1040                  * to set msg->im_mbz to "mbz" :-)
1041                  */
1042                 skb_push(skb, sizeof(struct iphdr));
1043                 skb_reset_network_header(skb);
1044                 skb_reset_transport_header(skb);
1045                 msg = (struct igmpmsg *)skb_network_header(skb);
1046                 memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
1047                 msg->im_msgtype = assert;
1048                 msg->im_mbz = 0;
1049                 if (assert == IGMPMSG_WRVIFWHOLE) {
1050                         msg->im_vif = vifi;
1051                         msg->im_vif_hi = vifi >> 8;
1052                 } else {
1053                         /* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */
1054                         int vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
1055
1056                         msg->im_vif = vif_num;
1057                         msg->im_vif_hi = vif_num >> 8;
1058                 }
1059                 ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
1060                 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
1061                                              sizeof(struct iphdr));
1062         } else {
1063                 /* Copy the IP header */
1064                 skb_set_network_header(skb, skb->len);
1065                 skb_put(skb, ihl);
1066                 skb_copy_to_linear_data(skb, pkt->data, ihl);
1067                 /* Flag to the kernel this is a route add */
1068                 ip_hdr(skb)->protocol = 0;
1069                 msg = (struct igmpmsg *)skb_network_header(skb);
1070                 msg->im_vif = vifi;
1071                 msg->im_vif_hi = vifi >> 8;
1072                 skb_dst_set(skb, dst_clone(skb_dst(pkt)));
1073                 /* Add our header */
1074                 igmp = skb_put(skb, sizeof(struct igmphdr));
1075                 igmp->type = assert;
1076                 msg->im_msgtype = assert;
1077                 igmp->code = 0;
1078                 ip_hdr(skb)->tot_len = htons(skb->len); /* Fix the length */
1079                 skb->transport_header = skb->network_header;
1080         }
1081
1082         mroute_sk = rcu_dereference(mrt->mroute_sk);
1083         if (!mroute_sk) {
1084                 kfree_skb(skb);
1085                 return -EINVAL;
1086         }
1087
1088         igmpmsg_netlink_event(mrt, skb);
1089
1090         /* Deliver to mrouted */
1091         ret = sock_queue_rcv_skb(mroute_sk, skb);
1092
1093         if (ret < 0) {
1094                 net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1095                 kfree_skb(skb);
1096         }
1097
1098         return ret;
1099 }
1100
1101 /* Queue a packet for resolution. It gets locked cache entry! */
1102 /* Called under rcu_read_lock() */
1103 static int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi,
1104                                  struct sk_buff *skb, struct net_device *dev)
1105 {
1106         const struct iphdr *iph = ip_hdr(skb);
1107         struct mfc_cache *c;
1108         bool found = false;
1109         int err;
1110
1111         spin_lock_bh(&mfc_unres_lock);
1112         list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
1113                 if (c->mfc_mcastgrp == iph->daddr &&
1114                     c->mfc_origin == iph->saddr) {
1115                         found = true;
1116                         break;
1117                 }
1118         }
1119
1120         if (!found) {
1121                 /* Create a new entry if allowable */
1122                 c = ipmr_cache_alloc_unres();
1123                 if (!c) {
1124                         spin_unlock_bh(&mfc_unres_lock);
1125
1126                         kfree_skb(skb);
1127                         return -ENOBUFS;
1128                 }
1129
1130                 /* Fill in the new cache entry */
1131                 c->_c.mfc_parent = -1;
1132                 c->mfc_origin   = iph->saddr;
1133                 c->mfc_mcastgrp = iph->daddr;
1134
1135                 /* Reflect first query at mrouted. */
1136                 err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1137
1138                 if (err < 0) {
1139                         /* If the report failed throw the cache entry
1140                            out - Brad Parker
1141                          */
1142                         spin_unlock_bh(&mfc_unres_lock);
1143
1144                         ipmr_cache_free(c);
1145                         kfree_skb(skb);
1146                         return err;
1147                 }
1148
1149                 atomic_inc(&mrt->cache_resolve_queue_len);
1150                 list_add(&c->_c.list, &mrt->mfc_unres_queue);
1151                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1152
1153                 if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1154                         mod_timer(&mrt->ipmr_expire_timer,
1155                                   c->_c.mfc_un.unres.expires);
1156         }
1157
1158         /* See if we can append the packet */
1159         if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
1160                 kfree_skb(skb);
1161                 err = -ENOBUFS;
1162         } else {
1163                 if (dev) {
1164                         skb->dev = dev;
1165                         skb->skb_iif = dev->ifindex;
1166                 }
1167                 skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
1168                 err = 0;
1169         }
1170
1171         spin_unlock_bh(&mfc_unres_lock);
1172         return err;
1173 }
1174
1175 /* MFC cache manipulation by user space mroute daemon */
1176
1177 static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1178 {
1179         struct net *net = read_pnet(&mrt->net);
1180         struct mfc_cache *c;
1181
1182         /* The entries are added/deleted only under RTNL */
1183         rcu_read_lock();
1184         c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1185                                    mfc->mfcc_mcastgrp.s_addr, parent);
1186         rcu_read_unlock();
1187         if (!c)
1188                 return -ENOENT;
1189         rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ipmr_rht_params);
1190         list_del_rcu(&c->_c.list);
1191         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id);
1192         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1193         mr_cache_put(&c->_c);
1194
1195         return 0;
1196 }
1197
1198 static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1199                         struct mfcctl *mfc, int mrtsock, int parent)
1200 {
1201         struct mfc_cache *uc, *c;
1202         struct mr_mfc *_uc;
1203         bool found;
1204         int ret;
1205
1206         if (mfc->mfcc_parent >= MAXVIFS)
1207                 return -ENFILE;
1208
1209         /* The entries are added/deleted only under RTNL */
1210         rcu_read_lock();
1211         c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1212                                    mfc->mfcc_mcastgrp.s_addr, parent);
1213         rcu_read_unlock();
1214         if (c) {
1215                 spin_lock(&mrt_lock);
1216                 c->_c.mfc_parent = mfc->mfcc_parent;
1217                 ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1218                 if (!mrtsock)
1219                         c->_c.mfc_flags |= MFC_STATIC;
1220                 spin_unlock(&mrt_lock);
1221                 call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c,
1222                                               mrt->id);
1223                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1224                 return 0;
1225         }
1226
1227         if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1228             !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1229                 return -EINVAL;
1230
1231         c = ipmr_cache_alloc();
1232         if (!c)
1233                 return -ENOMEM;
1234
1235         c->mfc_origin = mfc->mfcc_origin.s_addr;
1236         c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1237         c->_c.mfc_parent = mfc->mfcc_parent;
1238         ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1239         if (!mrtsock)
1240                 c->_c.mfc_flags |= MFC_STATIC;
1241
1242         ret = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
1243                                   ipmr_rht_params);
1244         if (ret) {
1245                 pr_err("ipmr: rhtable insert error %d\n", ret);
1246                 ipmr_cache_free(c);
1247                 return ret;
1248         }
1249         list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
1250         /* Check to see if we resolved a queued list. If so we
1251          * need to send on the frames and tidy up.
1252          */
1253         found = false;
1254         spin_lock_bh(&mfc_unres_lock);
1255         list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
1256                 uc = (struct mfc_cache *)_uc;
1257                 if (uc->mfc_origin == c->mfc_origin &&
1258                     uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1259                         list_del(&_uc->list);
1260                         atomic_dec(&mrt->cache_resolve_queue_len);
1261                         found = true;
1262                         break;
1263                 }
1264         }
1265         if (list_empty(&mrt->mfc_unres_queue))
1266                 del_timer(&mrt->ipmr_expire_timer);
1267         spin_unlock_bh(&mfc_unres_lock);
1268
1269         if (found) {
1270                 ipmr_cache_resolve(net, mrt, uc, c);
1271                 ipmr_cache_free(uc);
1272         }
1273         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, c, mrt->id);
1274         mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1275         return 0;
1276 }
1277
1278 /* Close the multicast socket, and clear the vif tables etc */
1279 static void mroute_clean_tables(struct mr_table *mrt, int flags)
1280 {
1281         struct net *net = read_pnet(&mrt->net);
1282         struct mr_mfc *c, *tmp;
1283         struct mfc_cache *cache;
1284         LIST_HEAD(list);
1285         int i;
1286
1287         /* Shut down all active vif entries */
1288         if (flags & (MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC)) {
1289                 for (i = 0; i < mrt->maxvif; i++) {
1290                         if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
1291                              !(flags & MRT_FLUSH_VIFS_STATIC)) ||
1292                             (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT_FLUSH_VIFS)))
1293                                 continue;
1294                         vif_delete(mrt, i, 0, &list);
1295                 }
1296                 unregister_netdevice_many(&list);
1297         }
1298
1299         /* Wipe the cache */
1300         if (flags & (MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC)) {
1301                 list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
1302                         if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC_STATIC)) ||
1303                             (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC)))
1304                                 continue;
1305                         rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
1306                         list_del_rcu(&c->list);
1307                         cache = (struct mfc_cache *)c;
1308                         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
1309                                                       mrt->id);
1310                         mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1311                         mr_cache_put(c);
1312                 }
1313         }
1314
1315         if (flags & MRT_FLUSH_MFC) {
1316                 if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1317                         spin_lock_bh(&mfc_unres_lock);
1318                         list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
1319                                 list_del(&c->list);
1320                                 cache = (struct mfc_cache *)c;
1321                                 mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1322                                 ipmr_destroy_unres(mrt, cache);
1323                         }
1324                         spin_unlock_bh(&mfc_unres_lock);
1325                 }
1326         }
1327 }
1328
1329 /* called from ip_ra_control(), before an RCU grace period,
1330  * we don't need to call synchronize_rcu() here
1331  */
1332 static void mrtsock_destruct(struct sock *sk)
1333 {
1334         struct net *net = sock_net(sk);
1335         struct mr_table *mrt;
1336
1337         rtnl_lock();
1338         ipmr_for_each_table(mrt, net) {
1339                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1340                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1341                         inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1342                                                     NETCONFA_MC_FORWARDING,
1343                                                     NETCONFA_IFINDEX_ALL,
1344                                                     net->ipv4.devconf_all);
1345                         RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1346                         mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_MFC);
1347                 }
1348         }
1349         rtnl_unlock();
1350 }
1351
1352 /* Socket options and virtual interface manipulation. The whole
1353  * virtual interface system is a complete heap, but unfortunately
1354  * that's how BSD mrouted happens to think. Maybe one day with a proper
1355  * MOSPF/PIM router set up we can clean this up.
1356  */
1357
1358 int ip_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval,
1359                          unsigned int optlen)
1360 {
1361         struct net *net = sock_net(sk);
1362         int val, ret = 0, parent = 0;
1363         struct mr_table *mrt;
1364         struct vifctl vif;
1365         struct mfcctl mfc;
1366         bool do_wrvifwhole;
1367         u32 uval;
1368
1369         /* There's one exception to the lock - MRT_DONE which needs to unlock */
1370         rtnl_lock();
1371         if (sk->sk_type != SOCK_RAW ||
1372             inet_sk(sk)->inet_num != IPPROTO_IGMP) {
1373                 ret = -EOPNOTSUPP;
1374                 goto out_unlock;
1375         }
1376
1377         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1378         if (!mrt) {
1379                 ret = -ENOENT;
1380                 goto out_unlock;
1381         }
1382         if (optname != MRT_INIT) {
1383                 if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1384                     !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
1385                         ret = -EACCES;
1386                         goto out_unlock;
1387                 }
1388         }
1389
1390         switch (optname) {
1391         case MRT_INIT:
1392                 if (optlen != sizeof(int)) {
1393                         ret = -EINVAL;
1394                         break;
1395                 }
1396                 if (rtnl_dereference(mrt->mroute_sk)) {
1397                         ret = -EADDRINUSE;
1398                         break;
1399                 }
1400
1401                 ret = ip_ra_control(sk, 1, mrtsock_destruct);
1402                 if (ret == 0) {
1403                         rcu_assign_pointer(mrt->mroute_sk, sk);
1404                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1405                         inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1406                                                     NETCONFA_MC_FORWARDING,
1407                                                     NETCONFA_IFINDEX_ALL,
1408                                                     net->ipv4.devconf_all);
1409                 }
1410                 break;
1411         case MRT_DONE:
1412                 if (sk != rcu_access_pointer(mrt->mroute_sk)) {
1413                         ret = -EACCES;
1414                 } else {
1415                         /* We need to unlock here because mrtsock_destruct takes
1416                          * care of rtnl itself and we can't change that due to
1417                          * the IP_ROUTER_ALERT setsockopt which runs without it.
1418                          */
1419                         rtnl_unlock();
1420                         ret = ip_ra_control(sk, 0, NULL);
1421                         goto out;
1422                 }
1423                 break;
1424         case MRT_ADD_VIF:
1425         case MRT_DEL_VIF:
1426                 if (optlen != sizeof(vif)) {
1427                         ret = -EINVAL;
1428                         break;
1429                 }
1430                 if (copy_from_sockptr(&vif, optval, sizeof(vif))) {
1431                         ret = -EFAULT;
1432                         break;
1433                 }
1434                 if (vif.vifc_vifi >= MAXVIFS) {
1435                         ret = -ENFILE;
1436                         break;
1437                 }
1438                 if (optname == MRT_ADD_VIF) {
1439                         ret = vif_add(net, mrt, &vif,
1440                                       sk == rtnl_dereference(mrt->mroute_sk));
1441                 } else {
1442                         ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1443                 }
1444                 break;
1445         /* Manipulate the forwarding caches. These live
1446          * in a sort of kernel/user symbiosis.
1447          */
1448         case MRT_ADD_MFC:
1449         case MRT_DEL_MFC:
1450                 parent = -1;
1451                 fallthrough;
1452         case MRT_ADD_MFC_PROXY:
1453         case MRT_DEL_MFC_PROXY:
1454                 if (optlen != sizeof(mfc)) {
1455                         ret = -EINVAL;
1456                         break;
1457                 }
1458                 if (copy_from_sockptr(&mfc, optval, sizeof(mfc))) {
1459                         ret = -EFAULT;
1460                         break;
1461                 }
1462                 if (parent == 0)
1463                         parent = mfc.mfcc_parent;
1464                 if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1465                         ret = ipmr_mfc_delete(mrt, &mfc, parent);
1466                 else
1467                         ret = ipmr_mfc_add(net, mrt, &mfc,
1468                                            sk == rtnl_dereference(mrt->mroute_sk),
1469                                            parent);
1470                 break;
1471         case MRT_FLUSH:
1472                 if (optlen != sizeof(val)) {
1473                         ret = -EINVAL;
1474                         break;
1475                 }
1476                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1477                         ret = -EFAULT;
1478                         break;
1479                 }
1480                 mroute_clean_tables(mrt, val);
1481                 break;
1482         /* Control PIM assert. */
1483         case MRT_ASSERT:
1484                 if (optlen != sizeof(val)) {
1485                         ret = -EINVAL;
1486                         break;
1487                 }
1488                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1489                         ret = -EFAULT;
1490                         break;
1491                 }
1492                 mrt->mroute_do_assert = val;
1493                 break;
1494         case MRT_PIM:
1495                 if (!ipmr_pimsm_enabled()) {
1496                         ret = -ENOPROTOOPT;
1497                         break;
1498                 }
1499                 if (optlen != sizeof(val)) {
1500                         ret = -EINVAL;
1501                         break;
1502                 }
1503                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1504                         ret = -EFAULT;
1505                         break;
1506                 }
1507
1508                 do_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE);
1509                 val = !!val;
1510                 if (val != mrt->mroute_do_pim) {
1511                         mrt->mroute_do_pim = val;
1512                         mrt->mroute_do_assert = val;
1513                         mrt->mroute_do_wrvifwhole = do_wrvifwhole;
1514                 }
1515                 break;
1516         case MRT_TABLE:
1517                 if (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) {
1518                         ret = -ENOPROTOOPT;
1519                         break;
1520                 }
1521                 if (optlen != sizeof(uval)) {
1522                         ret = -EINVAL;
1523                         break;
1524                 }
1525                 if (copy_from_sockptr(&uval, optval, sizeof(uval))) {
1526                         ret = -EFAULT;
1527                         break;
1528                 }
1529
1530                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1531                         ret = -EBUSY;
1532                 } else {
1533                         mrt = ipmr_new_table(net, uval);
1534                         if (IS_ERR(mrt))
1535                                 ret = PTR_ERR(mrt);
1536                         else
1537                                 raw_sk(sk)->ipmr_table = uval;
1538                 }
1539                 break;
1540         /* Spurious command, or MRT_VERSION which you cannot set. */
1541         default:
1542                 ret = -ENOPROTOOPT;
1543         }
1544 out_unlock:
1545         rtnl_unlock();
1546 out:
1547         return ret;
1548 }
1549
1550 /* Execute if this ioctl is a special mroute ioctl */
1551 int ipmr_sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1552 {
1553         switch (cmd) {
1554         /* These userspace buffers will be consumed by ipmr_ioctl() */
1555         case SIOCGETVIFCNT: {
1556                 struct sioc_vif_req buffer;
1557
1558                 return sock_ioctl_inout(sk, cmd, arg, &buffer,
1559                                       sizeof(buffer));
1560                 }
1561         case SIOCGETSGCNT: {
1562                 struct sioc_sg_req buffer;
1563
1564                 return sock_ioctl_inout(sk, cmd, arg, &buffer,
1565                                       sizeof(buffer));
1566                 }
1567         }
1568         /* return code > 0 means that the ioctl was not executed */
1569         return 1;
1570 }
1571
1572 /* Getsock opt support for the multicast routing system. */
1573 int ip_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval,
1574                          sockptr_t optlen)
1575 {
1576         int olr;
1577         int val;
1578         struct net *net = sock_net(sk);
1579         struct mr_table *mrt;
1580
1581         if (sk->sk_type != SOCK_RAW ||
1582             inet_sk(sk)->inet_num != IPPROTO_IGMP)
1583                 return -EOPNOTSUPP;
1584
1585         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1586         if (!mrt)
1587                 return -ENOENT;
1588
1589         switch (optname) {
1590         case MRT_VERSION:
1591                 val = 0x0305;
1592                 break;
1593         case MRT_PIM:
1594                 if (!ipmr_pimsm_enabled())
1595                         return -ENOPROTOOPT;
1596                 val = mrt->mroute_do_pim;
1597                 break;
1598         case MRT_ASSERT:
1599                 val = mrt->mroute_do_assert;
1600                 break;
1601         default:
1602                 return -ENOPROTOOPT;
1603         }
1604
1605         if (copy_from_sockptr(&olr, optlen, sizeof(int)))
1606                 return -EFAULT;
1607         olr = min_t(unsigned int, olr, sizeof(int));
1608         if (olr < 0)
1609                 return -EINVAL;
1610         if (copy_to_sockptr(optlen, &olr, sizeof(int)))
1611                 return -EFAULT;
1612         if (copy_to_sockptr(optval, &val, olr))
1613                 return -EFAULT;
1614         return 0;
1615 }
1616
1617 /* The IP multicast ioctl support routines. */
1618 int ipmr_ioctl(struct sock *sk, int cmd, void *arg)
1619 {
1620         struct vif_device *vif;
1621         struct mfc_cache *c;
1622         struct net *net = sock_net(sk);
1623         struct sioc_vif_req *vr;
1624         struct sioc_sg_req *sr;
1625         struct mr_table *mrt;
1626
1627         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1628         if (!mrt)
1629                 return -ENOENT;
1630
1631         switch (cmd) {
1632         case SIOCGETVIFCNT:
1633                 vr = (struct sioc_vif_req *)arg;
1634                 if (vr->vifi >= mrt->maxvif)
1635                         return -EINVAL;
1636                 vr->vifi = array_index_nospec(vr->vifi, mrt->maxvif);
1637                 rcu_read_lock();
1638                 vif = &mrt->vif_table[vr->vifi];
1639                 if (VIF_EXISTS(mrt, vr->vifi)) {
1640                         vr->icount = READ_ONCE(vif->pkt_in);
1641                         vr->ocount = READ_ONCE(vif->pkt_out);
1642                         vr->ibytes = READ_ONCE(vif->bytes_in);
1643                         vr->obytes = READ_ONCE(vif->bytes_out);
1644                         rcu_read_unlock();
1645
1646                         return 0;
1647                 }
1648                 rcu_read_unlock();
1649                 return -EADDRNOTAVAIL;
1650         case SIOCGETSGCNT:
1651                 sr = (struct sioc_sg_req *)arg;
1652
1653                 rcu_read_lock();
1654                 c = ipmr_cache_find(mrt, sr->src.s_addr, sr->grp.s_addr);
1655                 if (c) {
1656                         sr->pktcnt = c->_c.mfc_un.res.pkt;
1657                         sr->bytecnt = c->_c.mfc_un.res.bytes;
1658                         sr->wrong_if = c->_c.mfc_un.res.wrong_if;
1659                         rcu_read_unlock();
1660                         return 0;
1661                 }
1662                 rcu_read_unlock();
1663                 return -EADDRNOTAVAIL;
1664         default:
1665                 return -ENOIOCTLCMD;
1666         }
1667 }
1668
1669 #ifdef CONFIG_COMPAT
1670 struct compat_sioc_sg_req {
1671         struct in_addr src;
1672         struct in_addr grp;
1673         compat_ulong_t pktcnt;
1674         compat_ulong_t bytecnt;
1675         compat_ulong_t wrong_if;
1676 };
1677
1678 struct compat_sioc_vif_req {
1679         vifi_t  vifi;           /* Which iface */
1680         compat_ulong_t icount;
1681         compat_ulong_t ocount;
1682         compat_ulong_t ibytes;
1683         compat_ulong_t obytes;
1684 };
1685
1686 int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1687 {
1688         struct compat_sioc_sg_req sr;
1689         struct compat_sioc_vif_req vr;
1690         struct vif_device *vif;
1691         struct mfc_cache *c;
1692         struct net *net = sock_net(sk);
1693         struct mr_table *mrt;
1694
1695         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1696         if (!mrt)
1697                 return -ENOENT;
1698
1699         switch (cmd) {
1700         case SIOCGETVIFCNT:
1701                 if (copy_from_user(&vr, arg, sizeof(vr)))
1702                         return -EFAULT;
1703                 if (vr.vifi >= mrt->maxvif)
1704                         return -EINVAL;
1705                 vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
1706                 rcu_read_lock();
1707                 vif = &mrt->vif_table[vr.vifi];
1708                 if (VIF_EXISTS(mrt, vr.vifi)) {
1709                         vr.icount = READ_ONCE(vif->pkt_in);
1710                         vr.ocount = READ_ONCE(vif->pkt_out);
1711                         vr.ibytes = READ_ONCE(vif->bytes_in);
1712                         vr.obytes = READ_ONCE(vif->bytes_out);
1713                         rcu_read_unlock();
1714
1715                         if (copy_to_user(arg, &vr, sizeof(vr)))
1716                                 return -EFAULT;
1717                         return 0;
1718                 }
1719                 rcu_read_unlock();
1720                 return -EADDRNOTAVAIL;
1721         case SIOCGETSGCNT:
1722                 if (copy_from_user(&sr, arg, sizeof(sr)))
1723                         return -EFAULT;
1724
1725                 rcu_read_lock();
1726                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1727                 if (c) {
1728                         sr.pktcnt = c->_c.mfc_un.res.pkt;
1729                         sr.bytecnt = c->_c.mfc_un.res.bytes;
1730                         sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1731                         rcu_read_unlock();
1732
1733                         if (copy_to_user(arg, &sr, sizeof(sr)))
1734                                 return -EFAULT;
1735                         return 0;
1736                 }
1737                 rcu_read_unlock();
1738                 return -EADDRNOTAVAIL;
1739         default:
1740                 return -ENOIOCTLCMD;
1741         }
1742 }
1743 #endif
1744
1745 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1746 {
1747         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1748         struct net *net = dev_net(dev);
1749         struct mr_table *mrt;
1750         struct vif_device *v;
1751         int ct;
1752
1753         if (event != NETDEV_UNREGISTER)
1754                 return NOTIFY_DONE;
1755
1756         ipmr_for_each_table(mrt, net) {
1757                 v = &mrt->vif_table[0];
1758                 for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1759                         if (rcu_access_pointer(v->dev) == dev)
1760                                 vif_delete(mrt, ct, 1, NULL);
1761                 }
1762         }
1763         return NOTIFY_DONE;
1764 }
1765
1766 static struct notifier_block ip_mr_notifier = {
1767         .notifier_call = ipmr_device_event,
1768 };
1769
1770 /* Encapsulate a packet by attaching a valid IPIP header to it.
1771  * This avoids tunnel drivers and other mess and gives us the speed so
1772  * important for multicast video.
1773  */
1774 static void ip_encap(struct net *net, struct sk_buff *skb,
1775                      __be32 saddr, __be32 daddr)
1776 {
1777         struct iphdr *iph;
1778         const struct iphdr *old_iph = ip_hdr(skb);
1779
1780         skb_push(skb, sizeof(struct iphdr));
1781         skb->transport_header = skb->network_header;
1782         skb_reset_network_header(skb);
1783         iph = ip_hdr(skb);
1784
1785         iph->version    =       4;
1786         iph->tos        =       old_iph->tos;
1787         iph->ttl        =       old_iph->ttl;
1788         iph->frag_off   =       0;
1789         iph->daddr      =       daddr;
1790         iph->saddr      =       saddr;
1791         iph->protocol   =       IPPROTO_IPIP;
1792         iph->ihl        =       5;
1793         iph->tot_len    =       htons(skb->len);
1794         ip_select_ident(net, skb, NULL);
1795         ip_send_check(iph);
1796
1797         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1798         nf_reset_ct(skb);
1799 }
1800
1801 static inline int ipmr_forward_finish(struct net *net, struct sock *sk,
1802                                       struct sk_buff *skb)
1803 {
1804         struct ip_options *opt = &(IPCB(skb)->opt);
1805
1806         IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
1807         IP_ADD_STATS(net, IPSTATS_MIB_OUTOCTETS, skb->len);
1808
1809         if (unlikely(opt->optlen))
1810                 ip_forward_options(skb);
1811
1812         return dst_output(net, sk, skb);
1813 }
1814
1815 #ifdef CONFIG_NET_SWITCHDEV
1816 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1817                                    int in_vifi, int out_vifi)
1818 {
1819         struct vif_device *out_vif = &mrt->vif_table[out_vifi];
1820         struct vif_device *in_vif = &mrt->vif_table[in_vifi];
1821
1822         if (!skb->offload_l3_fwd_mark)
1823                 return false;
1824         if (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
1825                 return false;
1826         return netdev_phys_item_id_same(&out_vif->dev_parent_id,
1827                                         &in_vif->dev_parent_id);
1828 }
1829 #else
1830 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1831                                    int in_vifi, int out_vifi)
1832 {
1833         return false;
1834 }
1835 #endif
1836
1837 /* Processing handlers for ipmr_forward, under rcu_read_lock() */
1838
1839 static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1840                             int in_vifi, struct sk_buff *skb, int vifi)
1841 {
1842         const struct iphdr *iph = ip_hdr(skb);
1843         struct vif_device *vif = &mrt->vif_table[vifi];
1844         struct net_device *vif_dev;
1845         struct net_device *dev;
1846         struct rtable *rt;
1847         struct flowi4 fl4;
1848         int    encap = 0;
1849
1850         vif_dev = vif_dev_read(vif);
1851         if (!vif_dev)
1852                 goto out_free;
1853
1854         if (vif->flags & VIFF_REGISTER) {
1855                 WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1856                 WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1857                 DEV_STATS_ADD(vif_dev, tx_bytes, skb->len);
1858                 DEV_STATS_INC(vif_dev, tx_packets);
1859                 ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1860                 goto out_free;
1861         }
1862
1863         if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi))
1864                 goto out_free;
1865
1866         if (vif->flags & VIFF_TUNNEL) {
1867                 rt = ip_route_output_ports(net, &fl4, NULL,
1868                                            vif->remote, vif->local,
1869                                            0, 0,
1870                                            IPPROTO_IPIP,
1871                                            RT_TOS(iph->tos), vif->link);
1872                 if (IS_ERR(rt))
1873                         goto out_free;
1874                 encap = sizeof(struct iphdr);
1875         } else {
1876                 rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1877                                            0, 0,
1878                                            IPPROTO_IPIP,
1879                                            RT_TOS(iph->tos), vif->link);
1880                 if (IS_ERR(rt))
1881                         goto out_free;
1882         }
1883
1884         dev = rt->dst.dev;
1885
1886         if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1887                 /* Do not fragment multicasts. Alas, IPv4 does not
1888                  * allow to send ICMP, so that packets will disappear
1889                  * to blackhole.
1890                  */
1891                 IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
1892                 ip_rt_put(rt);
1893                 goto out_free;
1894         }
1895
1896         encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1897
1898         if (skb_cow(skb, encap)) {
1899                 ip_rt_put(rt);
1900                 goto out_free;
1901         }
1902
1903         WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1904         WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1905
1906         skb_dst_drop(skb);
1907         skb_dst_set(skb, &rt->dst);
1908         ip_decrease_ttl(ip_hdr(skb));
1909
1910         /* FIXME: forward and output firewalls used to be called here.
1911          * What do we do with netfilter? -- RR
1912          */
1913         if (vif->flags & VIFF_TUNNEL) {
1914                 ip_encap(net, skb, vif->local, vif->remote);
1915                 /* FIXME: extra output firewall step used to be here. --RR */
1916                 DEV_STATS_INC(vif_dev, tx_packets);
1917                 DEV_STATS_ADD(vif_dev, tx_bytes, skb->len);
1918         }
1919
1920         IPCB(skb)->flags |= IPSKB_FORWARDED;
1921
1922         /* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1923          * not only before forwarding, but after forwarding on all output
1924          * interfaces. It is clear, if mrouter runs a multicasting
1925          * program, it should receive packets not depending to what interface
1926          * program is joined.
1927          * If we will not make it, the program will have to join on all
1928          * interfaces. On the other hand, multihoming host (or router, but
1929          * not mrouter) cannot join to more than one interface - it will
1930          * result in receiving multiple packets.
1931          */
1932         NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
1933                 net, NULL, skb, skb->dev, dev,
1934                 ipmr_forward_finish);
1935         return;
1936
1937 out_free:
1938         kfree_skb(skb);
1939 }
1940
1941 /* Called with mrt_lock or rcu_read_lock() */
1942 static int ipmr_find_vif(const struct mr_table *mrt, struct net_device *dev)
1943 {
1944         int ct;
1945         /* Pairs with WRITE_ONCE() in vif_delete()/vif_add() */
1946         for (ct = READ_ONCE(mrt->maxvif) - 1; ct >= 0; ct--) {
1947                 if (rcu_access_pointer(mrt->vif_table[ct].dev) == dev)
1948                         break;
1949         }
1950         return ct;
1951 }
1952
1953 /* "local" means that we should preserve one skb (for local delivery) */
1954 /* Called uner rcu_read_lock() */
1955 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1956                           struct net_device *dev, struct sk_buff *skb,
1957                           struct mfc_cache *c, int local)
1958 {
1959         int true_vifi = ipmr_find_vif(mrt, dev);
1960         int psend = -1;
1961         int vif, ct;
1962
1963         vif = c->_c.mfc_parent;
1964         c->_c.mfc_un.res.pkt++;
1965         c->_c.mfc_un.res.bytes += skb->len;
1966         c->_c.mfc_un.res.lastuse = jiffies;
1967
1968         if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1969                 struct mfc_cache *cache_proxy;
1970
1971                 /* For an (*,G) entry, we only check that the incoming
1972                  * interface is part of the static tree.
1973                  */
1974                 cache_proxy = mr_mfc_find_any_parent(mrt, vif);
1975                 if (cache_proxy &&
1976                     cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
1977                         goto forward;
1978         }
1979
1980         /* Wrong interface: drop packet and (maybe) send PIM assert. */
1981         if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) {
1982                 if (rt_is_output_route(skb_rtable(skb))) {
1983                         /* It is our own packet, looped back.
1984                          * Very complicated situation...
1985                          *
1986                          * The best workaround until routing daemons will be
1987                          * fixed is not to redistribute packet, if it was
1988                          * send through wrong interface. It means, that
1989                          * multicast applications WILL NOT work for
1990                          * (S,G), which have default multicast route pointing
1991                          * to wrong oif. In any case, it is not a good
1992                          * idea to use multicasting applications on router.
1993                          */
1994                         goto dont_forward;
1995                 }
1996
1997                 c->_c.mfc_un.res.wrong_if++;
1998
1999                 if (true_vifi >= 0 && mrt->mroute_do_assert &&
2000                     /* pimsm uses asserts, when switching from RPT to SPT,
2001                      * so that we cannot check that packet arrived on an oif.
2002                      * It is bad, but otherwise we would need to move pretty
2003                      * large chunk of pimd to kernel. Ough... --ANK
2004                      */
2005                     (mrt->mroute_do_pim ||
2006                      c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
2007                     time_after(jiffies,
2008                                c->_c.mfc_un.res.last_assert +
2009                                MFC_ASSERT_THRESH)) {
2010                         c->_c.mfc_un.res.last_assert = jiffies;
2011                         ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
2012                         if (mrt->mroute_do_wrvifwhole)
2013                                 ipmr_cache_report(mrt, skb, true_vifi,
2014                                                   IGMPMSG_WRVIFWHOLE);
2015                 }
2016                 goto dont_forward;
2017         }
2018
2019 forward:
2020         WRITE_ONCE(mrt->vif_table[vif].pkt_in,
2021                    mrt->vif_table[vif].pkt_in + 1);
2022         WRITE_ONCE(mrt->vif_table[vif].bytes_in,
2023                    mrt->vif_table[vif].bytes_in + skb->len);
2024
2025         /* Forward the frame */
2026         if (c->mfc_origin == htonl(INADDR_ANY) &&
2027             c->mfc_mcastgrp == htonl(INADDR_ANY)) {
2028                 if (true_vifi >= 0 &&
2029                     true_vifi != c->_c.mfc_parent &&
2030                     ip_hdr(skb)->ttl >
2031                                 c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
2032                         /* It's an (*,*) entry and the packet is not coming from
2033                          * the upstream: forward the packet to the upstream
2034                          * only.
2035                          */
2036                         psend = c->_c.mfc_parent;
2037                         goto last_forward;
2038                 }
2039                 goto dont_forward;
2040         }
2041         for (ct = c->_c.mfc_un.res.maxvif - 1;
2042              ct >= c->_c.mfc_un.res.minvif; ct--) {
2043                 /* For (*,G) entry, don't forward to the incoming interface */
2044                 if ((c->mfc_origin != htonl(INADDR_ANY) ||
2045                      ct != true_vifi) &&
2046                     ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) {
2047                         if (psend != -1) {
2048                                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2049
2050                                 if (skb2)
2051                                         ipmr_queue_xmit(net, mrt, true_vifi,
2052                                                         skb2, psend);
2053                         }
2054                         psend = ct;
2055                 }
2056         }
2057 last_forward:
2058         if (psend != -1) {
2059                 if (local) {
2060                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2061
2062                         if (skb2)
2063                                 ipmr_queue_xmit(net, mrt, true_vifi, skb2,
2064                                                 psend);
2065                 } else {
2066                         ipmr_queue_xmit(net, mrt, true_vifi, skb, psend);
2067                         return;
2068                 }
2069         }
2070
2071 dont_forward:
2072         if (!local)
2073                 kfree_skb(skb);
2074 }
2075
2076 static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
2077 {
2078         struct rtable *rt = skb_rtable(skb);
2079         struct iphdr *iph = ip_hdr(skb);
2080         struct flowi4 fl4 = {
2081                 .daddr = iph->daddr,
2082                 .saddr = iph->saddr,
2083                 .flowi4_tos = RT_TOS(iph->tos),
2084                 .flowi4_oif = (rt_is_output_route(rt) ?
2085                                skb->dev->ifindex : 0),
2086                 .flowi4_iif = (rt_is_output_route(rt) ?
2087                                LOOPBACK_IFINDEX :
2088                                skb->dev->ifindex),
2089                 .flowi4_mark = skb->mark,
2090         };
2091         struct mr_table *mrt;
2092         int err;
2093
2094         err = ipmr_fib_lookup(net, &fl4, &mrt);
2095         if (err)
2096                 return ERR_PTR(err);
2097         return mrt;
2098 }
2099
2100 /* Multicast packets for forwarding arrive here
2101  * Called with rcu_read_lock();
2102  */
2103 int ip_mr_input(struct sk_buff *skb)
2104 {
2105         struct mfc_cache *cache;
2106         struct net *net = dev_net(skb->dev);
2107         int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
2108         struct mr_table *mrt;
2109         struct net_device *dev;
2110
2111         /* skb->dev passed in is the loX master dev for vrfs.
2112          * As there are no vifs associated with loopback devices,
2113          * get the proper interface that does have a vif associated with it.
2114          */
2115         dev = skb->dev;
2116         if (netif_is_l3_master(skb->dev)) {
2117                 dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
2118                 if (!dev) {
2119                         kfree_skb(skb);
2120                         return -ENODEV;
2121                 }
2122         }
2123
2124         /* Packet is looped back after forward, it should not be
2125          * forwarded second time, but still can be delivered locally.
2126          */
2127         if (IPCB(skb)->flags & IPSKB_FORWARDED)
2128                 goto dont_forward;
2129
2130         mrt = ipmr_rt_fib_lookup(net, skb);
2131         if (IS_ERR(mrt)) {
2132                 kfree_skb(skb);
2133                 return PTR_ERR(mrt);
2134         }
2135         if (!local) {
2136                 if (IPCB(skb)->opt.router_alert) {
2137                         if (ip_call_ra_chain(skb))
2138                                 return 0;
2139                 } else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
2140                         /* IGMPv1 (and broken IGMPv2 implementations sort of
2141                          * Cisco IOS <= 11.2(8)) do not put router alert
2142                          * option to IGMP packets destined to routable
2143                          * groups. It is very bad, because it means
2144                          * that we can forward NO IGMP messages.
2145                          */
2146                         struct sock *mroute_sk;
2147
2148                         mroute_sk = rcu_dereference(mrt->mroute_sk);
2149                         if (mroute_sk) {
2150                                 nf_reset_ct(skb);
2151                                 raw_rcv(mroute_sk, skb);
2152                                 return 0;
2153                         }
2154                 }
2155         }
2156
2157         /* already under rcu_read_lock() */
2158         cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
2159         if (!cache) {
2160                 int vif = ipmr_find_vif(mrt, dev);
2161
2162                 if (vif >= 0)
2163                         cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
2164                                                     vif);
2165         }
2166
2167         /* No usable cache entry */
2168         if (!cache) {
2169                 int vif;
2170
2171                 if (local) {
2172                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2173                         ip_local_deliver(skb);
2174                         if (!skb2)
2175                                 return -ENOBUFS;
2176                         skb = skb2;
2177                 }
2178
2179                 vif = ipmr_find_vif(mrt, dev);
2180                 if (vif >= 0)
2181                         return ipmr_cache_unresolved(mrt, vif, skb, dev);
2182                 kfree_skb(skb);
2183                 return -ENODEV;
2184         }
2185
2186         ip_mr_forward(net, mrt, dev, skb, cache, local);
2187
2188         if (local)
2189                 return ip_local_deliver(skb);
2190
2191         return 0;
2192
2193 dont_forward:
2194         if (local)
2195                 return ip_local_deliver(skb);
2196         kfree_skb(skb);
2197         return 0;
2198 }
2199
2200 #ifdef CONFIG_IP_PIMSM_V1
2201 /* Handle IGMP messages of PIMv1 */
2202 int pim_rcv_v1(struct sk_buff *skb)
2203 {
2204         struct igmphdr *pim;
2205         struct net *net = dev_net(skb->dev);
2206         struct mr_table *mrt;
2207
2208         if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2209                 goto drop;
2210
2211         pim = igmp_hdr(skb);
2212
2213         mrt = ipmr_rt_fib_lookup(net, skb);
2214         if (IS_ERR(mrt))
2215                 goto drop;
2216         if (!mrt->mroute_do_pim ||
2217             pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
2218                 goto drop;
2219
2220         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2221 drop:
2222                 kfree_skb(skb);
2223         }
2224         return 0;
2225 }
2226 #endif
2227
2228 #ifdef CONFIG_IP_PIMSM_V2
2229 static int pim_rcv(struct sk_buff *skb)
2230 {
2231         struct pimreghdr *pim;
2232         struct net *net = dev_net(skb->dev);
2233         struct mr_table *mrt;
2234
2235         if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2236                 goto drop;
2237
2238         pim = (struct pimreghdr *)skb_transport_header(skb);
2239         if (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) ||
2240             (pim->flags & PIM_NULL_REGISTER) ||
2241             (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
2242              csum_fold(skb_checksum(skb, 0, skb->len, 0))))
2243                 goto drop;
2244
2245         mrt = ipmr_rt_fib_lookup(net, skb);
2246         if (IS_ERR(mrt))
2247                 goto drop;
2248         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2249 drop:
2250                 kfree_skb(skb);
2251         }
2252         return 0;
2253 }
2254 #endif
2255
2256 int ipmr_get_route(struct net *net, struct sk_buff *skb,
2257                    __be32 saddr, __be32 daddr,
2258                    struct rtmsg *rtm, u32 portid)
2259 {
2260         struct mfc_cache *cache;
2261         struct mr_table *mrt;
2262         int err;
2263
2264         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2265         if (!mrt)
2266                 return -ENOENT;
2267
2268         rcu_read_lock();
2269         cache = ipmr_cache_find(mrt, saddr, daddr);
2270         if (!cache && skb->dev) {
2271                 int vif = ipmr_find_vif(mrt, skb->dev);
2272
2273                 if (vif >= 0)
2274                         cache = ipmr_cache_find_any(mrt, daddr, vif);
2275         }
2276         if (!cache) {
2277                 struct sk_buff *skb2;
2278                 struct iphdr *iph;
2279                 struct net_device *dev;
2280                 int vif = -1;
2281
2282                 dev = skb->dev;
2283                 if (dev)
2284                         vif = ipmr_find_vif(mrt, dev);
2285                 if (vif < 0) {
2286                         rcu_read_unlock();
2287                         return -ENODEV;
2288                 }
2289
2290                 skb2 = skb_realloc_headroom(skb, sizeof(struct iphdr));
2291                 if (!skb2) {
2292                         rcu_read_unlock();
2293                         return -ENOMEM;
2294                 }
2295
2296                 NETLINK_CB(skb2).portid = portid;
2297                 skb_push(skb2, sizeof(struct iphdr));
2298                 skb_reset_network_header(skb2);
2299                 iph = ip_hdr(skb2);
2300                 iph->ihl = sizeof(struct iphdr) >> 2;
2301                 iph->saddr = saddr;
2302                 iph->daddr = daddr;
2303                 iph->version = 0;
2304                 err = ipmr_cache_unresolved(mrt, vif, skb2, dev);
2305                 rcu_read_unlock();
2306                 return err;
2307         }
2308
2309         err = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
2310         rcu_read_unlock();
2311         return err;
2312 }
2313
2314 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2315                             u32 portid, u32 seq, struct mfc_cache *c, int cmd,
2316                             int flags)
2317 {
2318         struct nlmsghdr *nlh;
2319         struct rtmsg *rtm;
2320         int err;
2321
2322         nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2323         if (!nlh)
2324                 return -EMSGSIZE;
2325
2326         rtm = nlmsg_data(nlh);
2327         rtm->rtm_family   = RTNL_FAMILY_IPMR;
2328         rtm->rtm_dst_len  = 32;
2329         rtm->rtm_src_len  = 32;
2330         rtm->rtm_tos      = 0;
2331         rtm->rtm_table    = mrt->id;
2332         if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2333                 goto nla_put_failure;
2334         rtm->rtm_type     = RTN_MULTICAST;
2335         rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2336         if (c->_c.mfc_flags & MFC_STATIC)
2337                 rtm->rtm_protocol = RTPROT_STATIC;
2338         else
2339                 rtm->rtm_protocol = RTPROT_MROUTED;
2340         rtm->rtm_flags    = 0;
2341
2342         if (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) ||
2343             nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp))
2344                 goto nla_put_failure;
2345         err = mr_fill_mroute(mrt, skb, &c->_c, rtm);
2346         /* do not break the dump if cache is unresolved */
2347         if (err < 0 && err != -ENOENT)
2348                 goto nla_put_failure;
2349
2350         nlmsg_end(skb, nlh);
2351         return 0;
2352
2353 nla_put_failure:
2354         nlmsg_cancel(skb, nlh);
2355         return -EMSGSIZE;
2356 }
2357
2358 static int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2359                              u32 portid, u32 seq, struct mr_mfc *c, int cmd,
2360                              int flags)
2361 {
2362         return ipmr_fill_mroute(mrt, skb, portid, seq, (struct mfc_cache *)c,
2363                                 cmd, flags);
2364 }
2365
2366 static size_t mroute_msgsize(bool unresolved, int maxvif)
2367 {
2368         size_t len =
2369                 NLMSG_ALIGN(sizeof(struct rtmsg))
2370                 + nla_total_size(4)     /* RTA_TABLE */
2371                 + nla_total_size(4)     /* RTA_SRC */
2372                 + nla_total_size(4)     /* RTA_DST */
2373                 ;
2374
2375         if (!unresolved)
2376                 len = len
2377                       + nla_total_size(4)       /* RTA_IIF */
2378                       + nla_total_size(0)       /* RTA_MULTIPATH */
2379                       + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2380                                                 /* RTA_MFC_STATS */
2381                       + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
2382                 ;
2383
2384         return len;
2385 }
2386
2387 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2388                                  int cmd)
2389 {
2390         struct net *net = read_pnet(&mrt->net);
2391         struct sk_buff *skb;
2392         int err = -ENOBUFS;
2393
2394         skb = nlmsg_new(mroute_msgsize(mfc->_c.mfc_parent >= MAXVIFS,
2395                                        mrt->maxvif),
2396                         GFP_ATOMIC);
2397         if (!skb)
2398                 goto errout;
2399
2400         err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2401         if (err < 0)
2402                 goto errout;
2403
2404         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2405         return;
2406
2407 errout:
2408         kfree_skb(skb);
2409         if (err < 0)
2410                 rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
2411 }
2412
2413 static size_t igmpmsg_netlink_msgsize(size_t payloadlen)
2414 {
2415         size_t len =
2416                 NLMSG_ALIGN(sizeof(struct rtgenmsg))
2417                 + nla_total_size(1)     /* IPMRA_CREPORT_MSGTYPE */
2418                 + nla_total_size(4)     /* IPMRA_CREPORT_VIF_ID */
2419                 + nla_total_size(4)     /* IPMRA_CREPORT_SRC_ADDR */
2420                 + nla_total_size(4)     /* IPMRA_CREPORT_DST_ADDR */
2421                 + nla_total_size(4)     /* IPMRA_CREPORT_TABLE */
2422                                         /* IPMRA_CREPORT_PKT */
2423                 + nla_total_size(payloadlen)
2424                 ;
2425
2426         return len;
2427 }
2428
2429 static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt)
2430 {
2431         struct net *net = read_pnet(&mrt->net);
2432         struct nlmsghdr *nlh;
2433         struct rtgenmsg *rtgenm;
2434         struct igmpmsg *msg;
2435         struct sk_buff *skb;
2436         struct nlattr *nla;
2437         int payloadlen;
2438
2439         payloadlen = pkt->len - sizeof(struct igmpmsg);
2440         msg = (struct igmpmsg *)skb_network_header(pkt);
2441
2442         skb = nlmsg_new(igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2443         if (!skb)
2444                 goto errout;
2445
2446         nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
2447                         sizeof(struct rtgenmsg), 0);
2448         if (!nlh)
2449                 goto errout;
2450         rtgenm = nlmsg_data(nlh);
2451         rtgenm->rtgen_family = RTNL_FAMILY_IPMR;
2452         if (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) ||
2453             nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif | (msg->im_vif_hi << 8)) ||
2454             nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR,
2455                             msg->im_src.s_addr) ||
2456             nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR,
2457                             msg->im_dst.s_addr) ||
2458             nla_put_u32(skb, IPMRA_CREPORT_TABLE, mrt->id))
2459                 goto nla_put_failure;
2460
2461         nla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen);
2462         if (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg),
2463                                   nla_data(nla), payloadlen))
2464                 goto nla_put_failure;
2465
2466         nlmsg_end(skb, nlh);
2467
2468         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
2469         return;
2470
2471 nla_put_failure:
2472         nlmsg_cancel(skb, nlh);
2473 errout:
2474         kfree_skb(skb);
2475         rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS);
2476 }
2477
2478 static int ipmr_rtm_valid_getroute_req(struct sk_buff *skb,
2479                                        const struct nlmsghdr *nlh,
2480                                        struct nlattr **tb,
2481                                        struct netlink_ext_ack *extack)
2482 {
2483         struct rtmsg *rtm;
2484         int i, err;
2485
2486         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2487                 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for multicast route get request");
2488                 return -EINVAL;
2489         }
2490
2491         if (!netlink_strict_get_check(skb))
2492                 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
2493                                               rtm_ipv4_policy, extack);
2494
2495         rtm = nlmsg_data(nlh);
2496         if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) ||
2497             (rtm->rtm_dst_len && rtm->rtm_dst_len != 32) ||
2498             rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol ||
2499             rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) {
2500                 NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for multicast route get request");
2501                 return -EINVAL;
2502         }
2503
2504         err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2505                                             rtm_ipv4_policy, extack);
2506         if (err)
2507                 return err;
2508
2509         if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
2510             (tb[RTA_DST] && !rtm->rtm_dst_len)) {
2511                 NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4");
2512                 return -EINVAL;
2513         }
2514
2515         for (i = 0; i <= RTA_MAX; i++) {
2516                 if (!tb[i])
2517                         continue;
2518
2519                 switch (i) {
2520                 case RTA_SRC:
2521                 case RTA_DST:
2522                 case RTA_TABLE:
2523                         break;
2524                 default:
2525                         NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in multicast route get request");
2526                         return -EINVAL;
2527                 }
2528         }
2529
2530         return 0;
2531 }
2532
2533 static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2534                              struct netlink_ext_ack *extack)
2535 {
2536         struct net *net = sock_net(in_skb->sk);
2537         struct nlattr *tb[RTA_MAX + 1];
2538         struct sk_buff *skb = NULL;
2539         struct mfc_cache *cache;
2540         struct mr_table *mrt;
2541         __be32 src, grp;
2542         u32 tableid;
2543         int err;
2544
2545         err = ipmr_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
2546         if (err < 0)
2547                 goto errout;
2548
2549         src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
2550         grp = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
2551         tableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0;
2552
2553         mrt = ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT);
2554         if (!mrt) {
2555                 err = -ENOENT;
2556                 goto errout_free;
2557         }
2558
2559         /* entries are added/deleted only under RTNL */
2560         rcu_read_lock();
2561         cache = ipmr_cache_find(mrt, src, grp);
2562         rcu_read_unlock();
2563         if (!cache) {
2564                 err = -ENOENT;
2565                 goto errout_free;
2566         }
2567
2568         skb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL);
2569         if (!skb) {
2570                 err = -ENOBUFS;
2571                 goto errout_free;
2572         }
2573
2574         err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
2575                                nlh->nlmsg_seq, cache,
2576                                RTM_NEWROUTE, 0);
2577         if (err < 0)
2578                 goto errout_free;
2579
2580         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2581
2582 errout:
2583         return err;
2584
2585 errout_free:
2586         kfree_skb(skb);
2587         goto errout;
2588 }
2589
2590 static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2591 {
2592         struct fib_dump_filter filter = {};
2593         int err;
2594
2595         if (cb->strict_check) {
2596                 err = ip_valid_fib_dump_req(sock_net(skb->sk), cb->nlh,
2597                                             &filter, cb);
2598                 if (err < 0)
2599                         return err;
2600         }
2601
2602         if (filter.table_id) {
2603                 struct mr_table *mrt;
2604
2605                 mrt = ipmr_get_table(sock_net(skb->sk), filter.table_id);
2606                 if (!mrt) {
2607                         if (rtnl_msg_family(cb->nlh) != RTNL_FAMILY_IPMR)
2608                                 return skb->len;
2609
2610                         NL_SET_ERR_MSG(cb->extack, "ipv4: MR table does not exist");
2611                         return -ENOENT;
2612                 }
2613                 err = mr_table_dump(mrt, skb, cb, _ipmr_fill_mroute,
2614                                     &mfc_unres_lock, &filter);
2615                 return skb->len ? : err;
2616         }
2617
2618         return mr_rtm_dumproute(skb, cb, ipmr_mr_table_iter,
2619                                 _ipmr_fill_mroute, &mfc_unres_lock, &filter);
2620 }
2621
2622 static const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = {
2623         [RTA_SRC]       = { .type = NLA_U32 },
2624         [RTA_DST]       = { .type = NLA_U32 },
2625         [RTA_IIF]       = { .type = NLA_U32 },
2626         [RTA_TABLE]     = { .type = NLA_U32 },
2627         [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
2628 };
2629
2630 static bool ipmr_rtm_validate_proto(unsigned char rtm_protocol)
2631 {
2632         switch (rtm_protocol) {
2633         case RTPROT_STATIC:
2634         case RTPROT_MROUTED:
2635                 return true;
2636         }
2637         return false;
2638 }
2639
2640 static int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc)
2641 {
2642         struct rtnexthop *rtnh = nla_data(nla);
2643         int remaining = nla_len(nla), vifi = 0;
2644
2645         while (rtnh_ok(rtnh, remaining)) {
2646                 mfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops;
2647                 if (++vifi == MAXVIFS)
2648                         break;
2649                 rtnh = rtnh_next(rtnh, &remaining);
2650         }
2651
2652         return remaining > 0 ? -EINVAL : vifi;
2653 }
2654
2655 /* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY */
2656 static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh,
2657                             struct mfcctl *mfcc, int *mrtsock,
2658                             struct mr_table **mrtret,
2659                             struct netlink_ext_ack *extack)
2660 {
2661         struct net_device *dev = NULL;
2662         u32 tblid = RT_TABLE_DEFAULT;
2663         struct mr_table *mrt;
2664         struct nlattr *attr;
2665         struct rtmsg *rtm;
2666         int ret, rem;
2667
2668         ret = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX,
2669                                         rtm_ipmr_policy, extack);
2670         if (ret < 0)
2671                 goto out;
2672         rtm = nlmsg_data(nlh);
2673
2674         ret = -EINVAL;
2675         if (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 ||
2676             rtm->rtm_type != RTN_MULTICAST ||
2677             rtm->rtm_scope != RT_SCOPE_UNIVERSE ||
2678             !ipmr_rtm_validate_proto(rtm->rtm_protocol))
2679                 goto out;
2680
2681         memset(mfcc, 0, sizeof(*mfcc));
2682         mfcc->mfcc_parent = -1;
2683         ret = 0;
2684         nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) {
2685                 switch (nla_type(attr)) {
2686                 case RTA_SRC:
2687                         mfcc->mfcc_origin.s_addr = nla_get_be32(attr);
2688                         break;
2689                 case RTA_DST:
2690                         mfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr);
2691                         break;
2692                 case RTA_IIF:
2693                         dev = __dev_get_by_index(net, nla_get_u32(attr));
2694                         if (!dev) {
2695                                 ret = -ENODEV;
2696                                 goto out;
2697                         }
2698                         break;
2699                 case RTA_MULTIPATH:
2700                         if (ipmr_nla_get_ttls(attr, mfcc) < 0) {
2701                                 ret = -EINVAL;
2702                                 goto out;
2703                         }
2704                         break;
2705                 case RTA_PREFSRC:
2706                         ret = 1;
2707                         break;
2708                 case RTA_TABLE:
2709                         tblid = nla_get_u32(attr);
2710                         break;
2711                 }
2712         }
2713         mrt = ipmr_get_table(net, tblid);
2714         if (!mrt) {
2715                 ret = -ENOENT;
2716                 goto out;
2717         }
2718         *mrtret = mrt;
2719         *mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0;
2720         if (dev)
2721                 mfcc->mfcc_parent = ipmr_find_vif(mrt, dev);
2722
2723 out:
2724         return ret;
2725 }
2726
2727 /* takes care of both newroute and delroute */
2728 static int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh,
2729                           struct netlink_ext_ack *extack)
2730 {
2731         struct net *net = sock_net(skb->sk);
2732         int ret, mrtsock, parent;
2733         struct mr_table *tbl;
2734         struct mfcctl mfcc;
2735
2736         mrtsock = 0;
2737         tbl = NULL;
2738         ret = rtm_to_ipmr_mfcc(net, nlh, &mfcc, &mrtsock, &tbl, extack);
2739         if (ret < 0)
2740                 return ret;
2741
2742         parent = ret ? mfcc.mfcc_parent : -1;
2743         if (nlh->nlmsg_type == RTM_NEWROUTE)
2744                 return ipmr_mfc_add(net, tbl, &mfcc, mrtsock, parent);
2745         else
2746                 return ipmr_mfc_delete(tbl, &mfcc, parent);
2747 }
2748
2749 static bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb)
2750 {
2751         u32 queue_len = atomic_read(&mrt->cache_resolve_queue_len);
2752
2753         if (nla_put_u32(skb, IPMRA_TABLE_ID, mrt->id) ||
2754             nla_put_u32(skb, IPMRA_TABLE_CACHE_RES_QUEUE_LEN, queue_len) ||
2755             nla_put_s32(skb, IPMRA_TABLE_MROUTE_REG_VIF_NUM,
2756                         mrt->mroute_reg_vif_num) ||
2757             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_ASSERT,
2758                        mrt->mroute_do_assert) ||
2759             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_PIM, mrt->mroute_do_pim) ||
2760             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE,
2761                        mrt->mroute_do_wrvifwhole))
2762                 return false;
2763
2764         return true;
2765 }
2766
2767 static bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb)
2768 {
2769         struct net_device *vif_dev;
2770         struct nlattr *vif_nest;
2771         struct vif_device *vif;
2772
2773         vif = &mrt->vif_table[vifid];
2774         vif_dev = rtnl_dereference(vif->dev);
2775         /* if the VIF doesn't exist just continue */
2776         if (!vif_dev)
2777                 return true;
2778
2779         vif_nest = nla_nest_start_noflag(skb, IPMRA_VIF);
2780         if (!vif_nest)
2781                 return false;
2782
2783         if (nla_put_u32(skb, IPMRA_VIFA_IFINDEX, vif_dev->ifindex) ||
2784             nla_put_u32(skb, IPMRA_VIFA_VIF_ID, vifid) ||
2785             nla_put_u16(skb, IPMRA_VIFA_FLAGS, vif->flags) ||
2786             nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_IN, vif->bytes_in,
2787                               IPMRA_VIFA_PAD) ||
2788             nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_OUT, vif->bytes_out,
2789                               IPMRA_VIFA_PAD) ||
2790             nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_IN, vif->pkt_in,
2791                               IPMRA_VIFA_PAD) ||
2792             nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_OUT, vif->pkt_out,
2793                               IPMRA_VIFA_PAD) ||
2794             nla_put_be32(skb, IPMRA_VIFA_LOCAL_ADDR, vif->local) ||
2795             nla_put_be32(skb, IPMRA_VIFA_REMOTE_ADDR, vif->remote)) {
2796                 nla_nest_cancel(skb, vif_nest);
2797                 return false;
2798         }
2799         nla_nest_end(skb, vif_nest);
2800
2801         return true;
2802 }
2803
2804 static int ipmr_valid_dumplink(const struct nlmsghdr *nlh,
2805                                struct netlink_ext_ack *extack)
2806 {
2807         struct ifinfomsg *ifm;
2808
2809         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
2810                 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for ipmr link dump");
2811                 return -EINVAL;
2812         }
2813
2814         if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
2815                 NL_SET_ERR_MSG(extack, "Invalid data after header in ipmr link dump");
2816                 return -EINVAL;
2817         }
2818
2819         ifm = nlmsg_data(nlh);
2820         if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
2821             ifm->ifi_change || ifm->ifi_index) {
2822                 NL_SET_ERR_MSG(extack, "Invalid values in header for ipmr link dump request");
2823                 return -EINVAL;
2824         }
2825
2826         return 0;
2827 }
2828
2829 static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb)
2830 {
2831         struct net *net = sock_net(skb->sk);
2832         struct nlmsghdr *nlh = NULL;
2833         unsigned int t = 0, s_t;
2834         unsigned int e = 0, s_e;
2835         struct mr_table *mrt;
2836
2837         if (cb->strict_check) {
2838                 int err = ipmr_valid_dumplink(cb->nlh, cb->extack);
2839
2840                 if (err < 0)
2841                         return err;
2842         }
2843
2844         s_t = cb->args[0];
2845         s_e = cb->args[1];
2846
2847         ipmr_for_each_table(mrt, net) {
2848                 struct nlattr *vifs, *af;
2849                 struct ifinfomsg *hdr;
2850                 u32 i;
2851
2852                 if (t < s_t)
2853                         goto skip_table;
2854                 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
2855                                 cb->nlh->nlmsg_seq, RTM_NEWLINK,
2856                                 sizeof(*hdr), NLM_F_MULTI);
2857                 if (!nlh)
2858                         break;
2859
2860                 hdr = nlmsg_data(nlh);
2861                 memset(hdr, 0, sizeof(*hdr));
2862                 hdr->ifi_family = RTNL_FAMILY_IPMR;
2863
2864                 af = nla_nest_start_noflag(skb, IFLA_AF_SPEC);
2865                 if (!af) {
2866                         nlmsg_cancel(skb, nlh);
2867                         goto out;
2868                 }
2869
2870                 if (!ipmr_fill_table(mrt, skb)) {
2871                         nlmsg_cancel(skb, nlh);
2872                         goto out;
2873                 }
2874
2875                 vifs = nla_nest_start_noflag(skb, IPMRA_TABLE_VIFS);
2876                 if (!vifs) {
2877                         nla_nest_end(skb, af);
2878                         nlmsg_end(skb, nlh);
2879                         goto out;
2880                 }
2881                 for (i = 0; i < mrt->maxvif; i++) {
2882                         if (e < s_e)
2883                                 goto skip_entry;
2884                         if (!ipmr_fill_vif(mrt, i, skb)) {
2885                                 nla_nest_end(skb, vifs);
2886                                 nla_nest_end(skb, af);
2887                                 nlmsg_end(skb, nlh);
2888                                 goto out;
2889                         }
2890 skip_entry:
2891                         e++;
2892                 }
2893                 s_e = 0;
2894                 e = 0;
2895                 nla_nest_end(skb, vifs);
2896                 nla_nest_end(skb, af);
2897                 nlmsg_end(skb, nlh);
2898 skip_table:
2899                 t++;
2900         }
2901
2902 out:
2903         cb->args[1] = e;
2904         cb->args[0] = t;
2905
2906         return skb->len;
2907 }
2908
2909 #ifdef CONFIG_PROC_FS
2910 /* The /proc interfaces to multicast routing :
2911  * /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2912  */
2913
2914 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2915         __acquires(RCU)
2916 {
2917         struct mr_vif_iter *iter = seq->private;
2918         struct net *net = seq_file_net(seq);
2919         struct mr_table *mrt;
2920
2921         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2922         if (!mrt)
2923                 return ERR_PTR(-ENOENT);
2924
2925         iter->mrt = mrt;
2926
2927         rcu_read_lock();
2928         return mr_vif_seq_start(seq, pos);
2929 }
2930
2931 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2932         __releases(RCU)
2933 {
2934         rcu_read_unlock();
2935 }
2936
2937 static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2938 {
2939         struct mr_vif_iter *iter = seq->private;
2940         struct mr_table *mrt = iter->mrt;
2941
2942         if (v == SEQ_START_TOKEN) {
2943                 seq_puts(seq,
2944                          "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
2945         } else {
2946                 const struct vif_device *vif = v;
2947                 const struct net_device *vif_dev;
2948                 const char *name;
2949
2950                 vif_dev = vif_dev_read(vif);
2951                 name = vif_dev ? vif_dev->name : "none";
2952                 seq_printf(seq,
2953                            "%2td %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
2954                            vif - mrt->vif_table,
2955                            name, vif->bytes_in, vif->pkt_in,
2956                            vif->bytes_out, vif->pkt_out,
2957                            vif->flags, vif->local, vif->remote);
2958         }
2959         return 0;
2960 }
2961
2962 static const struct seq_operations ipmr_vif_seq_ops = {
2963         .start = ipmr_vif_seq_start,
2964         .next  = mr_vif_seq_next,
2965         .stop  = ipmr_vif_seq_stop,
2966         .show  = ipmr_vif_seq_show,
2967 };
2968
2969 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2970 {
2971         struct net *net = seq_file_net(seq);
2972         struct mr_table *mrt;
2973
2974         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2975         if (!mrt)
2976                 return ERR_PTR(-ENOENT);
2977
2978         return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
2979 }
2980
2981 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2982 {
2983         int n;
2984
2985         if (v == SEQ_START_TOKEN) {
2986                 seq_puts(seq,
2987                  "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
2988         } else {
2989                 const struct mfc_cache *mfc = v;
2990                 const struct mr_mfc_iter *it = seq->private;
2991                 const struct mr_table *mrt = it->mrt;
2992
2993                 seq_printf(seq, "%08X %08X %-3hd",
2994                            (__force u32) mfc->mfc_mcastgrp,
2995                            (__force u32) mfc->mfc_origin,
2996                            mfc->_c.mfc_parent);
2997
2998                 if (it->cache != &mrt->mfc_unres_queue) {
2999                         seq_printf(seq, " %8lu %8lu %8lu",
3000                                    mfc->_c.mfc_un.res.pkt,
3001                                    mfc->_c.mfc_un.res.bytes,
3002                                    mfc->_c.mfc_un.res.wrong_if);
3003                         for (n = mfc->_c.mfc_un.res.minvif;
3004                              n < mfc->_c.mfc_un.res.maxvif; n++) {
3005                                 if (VIF_EXISTS(mrt, n) &&
3006                                     mfc->_c.mfc_un.res.ttls[n] < 255)
3007                                         seq_printf(seq,
3008                                            " %2d:%-3d",
3009                                            n, mfc->_c.mfc_un.res.ttls[n]);
3010                         }
3011                 } else {
3012                         /* unresolved mfc_caches don't contain
3013                          * pkt, bytes and wrong_if values
3014                          */
3015                         seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
3016                 }
3017                 seq_putc(seq, '\n');
3018         }
3019         return 0;
3020 }
3021
3022 static const struct seq_operations ipmr_mfc_seq_ops = {
3023         .start = ipmr_mfc_seq_start,
3024         .next  = mr_mfc_seq_next,
3025         .stop  = mr_mfc_seq_stop,
3026         .show  = ipmr_mfc_seq_show,
3027 };
3028 #endif
3029
3030 #ifdef CONFIG_IP_PIMSM_V2
3031 static const struct net_protocol pim_protocol = {
3032         .handler        =       pim_rcv,
3033 };
3034 #endif
3035
3036 static unsigned int ipmr_seq_read(struct net *net)
3037 {
3038         ASSERT_RTNL();
3039
3040         return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
3041 }
3042
3043 static int ipmr_dump(struct net *net, struct notifier_block *nb,
3044                      struct netlink_ext_ack *extack)
3045 {
3046         return mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump,
3047                        ipmr_mr_table_iter, extack);
3048 }
3049
3050 static const struct fib_notifier_ops ipmr_notifier_ops_template = {
3051         .family         = RTNL_FAMILY_IPMR,
3052         .fib_seq_read   = ipmr_seq_read,
3053         .fib_dump       = ipmr_dump,
3054         .owner          = THIS_MODULE,
3055 };
3056
3057 static int __net_init ipmr_notifier_init(struct net *net)
3058 {
3059         struct fib_notifier_ops *ops;
3060
3061         net->ipv4.ipmr_seq = 0;
3062
3063         ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net);
3064         if (IS_ERR(ops))
3065                 return PTR_ERR(ops);
3066         net->ipv4.ipmr_notifier_ops = ops;
3067
3068         return 0;
3069 }
3070
3071 static void __net_exit ipmr_notifier_exit(struct net *net)
3072 {
3073         fib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops);
3074         net->ipv4.ipmr_notifier_ops = NULL;
3075 }
3076
3077 /* Setup for IP multicast routing */
3078 static int __net_init ipmr_net_init(struct net *net)
3079 {
3080         int err;
3081
3082         err = ipmr_notifier_init(net);
3083         if (err)
3084                 goto ipmr_notifier_fail;
3085
3086         err = ipmr_rules_init(net);
3087         if (err < 0)
3088                 goto ipmr_rules_fail;
3089
3090 #ifdef CONFIG_PROC_FS
3091         err = -ENOMEM;
3092         if (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops,
3093                         sizeof(struct mr_vif_iter)))
3094                 goto proc_vif_fail;
3095         if (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
3096                         sizeof(struct mr_mfc_iter)))
3097                 goto proc_cache_fail;
3098 #endif
3099         return 0;
3100
3101 #ifdef CONFIG_PROC_FS
3102 proc_cache_fail:
3103         remove_proc_entry("ip_mr_vif", net->proc_net);
3104 proc_vif_fail:
3105         rtnl_lock();
3106         ipmr_rules_exit(net);
3107         rtnl_unlock();
3108 #endif
3109 ipmr_rules_fail:
3110         ipmr_notifier_exit(net);
3111 ipmr_notifier_fail:
3112         return err;
3113 }
3114
3115 static void __net_exit ipmr_net_exit(struct net *net)
3116 {
3117 #ifdef CONFIG_PROC_FS
3118         remove_proc_entry("ip_mr_cache", net->proc_net);
3119         remove_proc_entry("ip_mr_vif", net->proc_net);
3120 #endif
3121         ipmr_notifier_exit(net);
3122 }
3123
3124 static void __net_exit ipmr_net_exit_batch(struct list_head *net_list)
3125 {
3126         struct net *net;
3127
3128         rtnl_lock();
3129         list_for_each_entry(net, net_list, exit_list)
3130                 ipmr_rules_exit(net);
3131         rtnl_unlock();
3132 }
3133
3134 static struct pernet_operations ipmr_net_ops = {
3135         .init = ipmr_net_init,
3136         .exit = ipmr_net_exit,
3137         .exit_batch = ipmr_net_exit_batch,
3138 };
3139
3140 int __init ip_mr_init(void)
3141 {
3142         int err;
3143
3144         mrt_cachep = kmem_cache_create("ip_mrt_cache",
3145                                        sizeof(struct mfc_cache),
3146                                        0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
3147                                        NULL);
3148
3149         err = register_pernet_subsys(&ipmr_net_ops);
3150         if (err)
3151                 goto reg_pernet_fail;
3152
3153         err = register_netdevice_notifier(&ip_mr_notifier);
3154         if (err)
3155                 goto reg_notif_fail;
3156 #ifdef CONFIG_IP_PIMSM_V2
3157         if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
3158                 pr_err("%s: can't add PIM protocol\n", __func__);
3159                 err = -EAGAIN;
3160                 goto add_proto_fail;
3161         }
3162 #endif
3163         rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
3164                       ipmr_rtm_getroute, ipmr_rtm_dumproute, 0);
3165         rtnl_register(RTNL_FAMILY_IPMR, RTM_NEWROUTE,
3166                       ipmr_rtm_route, NULL, 0);
3167         rtnl_register(RTNL_FAMILY_IPMR, RTM_DELROUTE,
3168                       ipmr_rtm_route, NULL, 0);
3169
3170         rtnl_register(RTNL_FAMILY_IPMR, RTM_GETLINK,
3171                       NULL, ipmr_rtm_dumplink, 0);
3172         return 0;
3173
3174 #ifdef CONFIG_IP_PIMSM_V2
3175 add_proto_fail:
3176         unregister_netdevice_notifier(&ip_mr_notifier);
3177 #endif
3178 reg_notif_fail:
3179         unregister_pernet_subsys(&ipmr_net_ops);
3180 reg_pernet_fail:
3181         kmem_cache_destroy(mrt_cachep);
3182         return err;
3183 }