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, <[email protected]>
   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 #include <net/inet_dscp.h>
  66
  67 #include <linux/nospec.h>
  68
  69 struct ipmr_rule {
  70         struct fib_rule         common;
  71 };
  72
  73 struct ipmr_result {
  74         struct mr_table         *mrt;
  75 };
  76
  77 /* Big lock, protecting vif table, mrt cache and mroute socket state.
  78  * Note that the changes are semaphored via rtnl_lock.
  79  */
  80
  81 static DEFINE_SPINLOCK(mrt_lock);
  82
  83 static struct net_device *vif_dev_read(const struct vif_device *vif)
  84 {
  85         return rcu_dereference(vif->dev);
  86 }
  87
  88 /* Multicast router control variables */
  89
  90 /* Special spinlock for queue of unresolved entries */
  91 static DEFINE_SPINLOCK(mfc_unres_lock);
  92
  93 /* We return to original Alan's scheme. Hash table of resolved
  94  * entries is changed only in process context and protected
  95  * with weak lock mrt_lock. Queue of unresolved entries is protected
  96  * with strong spinlock mfc_unres_lock.
  97  *
  98  * In this case data path is free of exclusive locks at all.
  99  */
 100
 101 static struct kmem_cache *mrt_cachep __ro_after_init;
 102
 103 static struct mr_table *ipmr_new_table(struct net *net, u32 id);
 104 static void ipmr_free_table(struct mr_table *mrt);
 105
 106 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
 107                           struct net_device *dev, struct sk_buff *skb,
 108                           struct mfc_cache *cache, int local);
 109 static int ipmr_cache_report(const struct mr_table *mrt,
 110                              struct sk_buff *pkt, vifi_t vifi, int assert);
 111 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
 112                                  int cmd);
 113 static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt);
 114 static void mroute_clean_tables(struct mr_table *mrt, int flags);
 115 static void ipmr_expire_process(struct timer_list *t);
 116
 117 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 118 #define ipmr_for_each_table(mrt, net)                                   \
 119         list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list,        \
 120                                 lockdep_rtnl_is_held() ||               \
 121                                 list_empty(&net->ipv4.mr_tables))
 122
 123 static bool ipmr_can_free_table(struct net *net)
 124 {
 125         return !check_net(net) || !net_initialized(net);
 126 }
 127
 128 static struct mr_table *ipmr_mr_table_iter(struct net *net,
 129                                            struct mr_table *mrt)
 130 {
 131         struct mr_table *ret;
 132
 133         if (!mrt)
 134                 ret = list_entry_rcu(net->ipv4.mr_tables.next,
 135                                      struct mr_table, list);
 136         else
 137                 ret = list_entry_rcu(mrt->list.next,
 138                                      struct mr_table, list);
 139
 140         if (&ret->list == &net->ipv4.mr_tables)
 141                 return NULL;
 142         return ret;
 143 }
 144
 145 static struct mr_table *__ipmr_get_table(struct net *net, u32 id)
 146 {
 147         struct mr_table *mrt;
 148
 149         ipmr_for_each_table(mrt, net) {
 150                 if (mrt->id == id)
 151                         return mrt;
 152         }
 153         return NULL;
 154 }
 155
 156 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 157 {
 158         struct mr_table *mrt;
 159
 160         rcu_read_lock();
 161         mrt = __ipmr_get_table(net, id);
 162         rcu_read_unlock();
 163         return mrt;
 164 }
 165
 166 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 167                            struct mr_table **mrt)
 168 {
 169         int err;
 170         struct ipmr_result res;
 171         struct fib_lookup_arg arg = {
 172                 .result = &res,
 173                 .flags = FIB_LOOKUP_NOREF,
 174         };
 175
 176         /* update flow if oif or iif point to device enslaved to l3mdev */
 177         l3mdev_update_flow(net, flowi4_to_flowi(flp4));
 178
 179         err = fib_rules_lookup(net->ipv4.mr_rules_ops,
 180                                flowi4_to_flowi(flp4), 0, &arg);
 181         if (err < 0)
 182                 return err;
 183         *mrt = res.mrt;
 184         return 0;
 185 }
 186
 187 static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
 188                             int flags, struct fib_lookup_arg *arg)
 189 {
 190         struct ipmr_result *res = arg->result;
 191         struct mr_table *mrt;
 192
 193         switch (rule->action) {
 194         case FR_ACT_TO_TBL:
 195                 break;
 196         case FR_ACT_UNREACHABLE:
 197                 return -ENETUNREACH;
 198         case FR_ACT_PROHIBIT:
 199                 return -EACCES;
 200         case FR_ACT_BLACKHOLE:
 201         default:
 202                 return -EINVAL;
 203         }
 204
 205         arg->table = fib_rule_get_table(rule, arg);
 206
 207         mrt = __ipmr_get_table(rule->fr_net, arg->table);
 208         if (!mrt)
 209                 return -EAGAIN;
 210         res->mrt = mrt;
 211         return 0;
 212 }
 213
 214 static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
 215 {
 216         return 1;
 217 }
 218
 219 static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
 220                                struct fib_rule_hdr *frh, struct nlattr **tb,
 221                                struct netlink_ext_ack *extack)
 222 {
 223         return 0;
 224 }
 225
 226 static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
 227                              struct nlattr **tb)
 228 {
 229         return 1;
 230 }
 231
 232 static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
 233                           struct fib_rule_hdr *frh)
 234 {
 235         frh->dst_len = 0;
 236         frh->src_len = 0;
 237         frh->tos     = 0;
 238         return 0;
 239 }
 240
 241 static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
 242         .family         = RTNL_FAMILY_IPMR,
 243         .rule_size      = sizeof(struct ipmr_rule),
 244         .addr_size      = sizeof(u32),
 245         .action         = ipmr_rule_action,
 246         .match          = ipmr_rule_match,
 247         .configure      = ipmr_rule_configure,
 248         .compare        = ipmr_rule_compare,
 249         .fill           = ipmr_rule_fill,
 250         .nlgroup        = RTNLGRP_IPV4_RULE,
 251         .owner          = THIS_MODULE,
 252 };
 253
 254 static int __net_init ipmr_rules_init(struct net *net)
 255 {
 256         struct fib_rules_ops *ops;
 257         struct mr_table *mrt;
 258         int err;
 259
 260         ops = fib_rules_register(&ipmr_rules_ops_template, net);
 261         if (IS_ERR(ops))
 262                 return PTR_ERR(ops);
 263
 264         INIT_LIST_HEAD(&net->ipv4.mr_tables);
 265
 266         mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 267         if (IS_ERR(mrt)) {
 268                 err = PTR_ERR(mrt);
 269                 goto err1;
 270         }
 271
 272         err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT);
 273         if (err < 0)
 274                 goto err2;
 275
 276         net->ipv4.mr_rules_ops = ops;
 277         return 0;
 278
 279 err2:
 280         rtnl_lock();
 281         ipmr_free_table(mrt);
 282         rtnl_unlock();
 283 err1:
 284         fib_rules_unregister(ops);
 285         return err;
 286 }
 287
 288 static void __net_exit ipmr_rules_exit(struct net *net)
 289 {
 290         struct mr_table *mrt, *next;
 291
 292         ASSERT_RTNL();
 293         list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
 294                 list_del(&mrt->list);
 295                 ipmr_free_table(mrt);
 296         }
 297         fib_rules_unregister(net->ipv4.mr_rules_ops);
 298 }
 299
 300 static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
 301                            struct netlink_ext_ack *extack)
 302 {
 303         return fib_rules_dump(net, nb, RTNL_FAMILY_IPMR, extack);
 304 }
 305
 306 static unsigned int ipmr_rules_seq_read(const struct net *net)
 307 {
 308         return fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
 309 }
 310
 311 bool ipmr_rule_default(const struct fib_rule *rule)
 312 {
 313         return fib_rule_matchall(rule) && rule->table == RT_TABLE_DEFAULT;
 314 }
 315 EXPORT_SYMBOL(ipmr_rule_default);
 316 #else
 317 #define ipmr_for_each_table(mrt, net) \
 318         for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
 319
 320 static bool ipmr_can_free_table(struct net *net)
 321 {
 322         return !check_net(net);
 323 }
 324
 325 static struct mr_table *ipmr_mr_table_iter(struct net *net,
 326                                            struct mr_table *mrt)
 327 {
 328         if (!mrt)
 329                 return net->ipv4.mrt;
 330         return NULL;
 331 }
 332
 333 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 334 {
 335         return net->ipv4.mrt;
 336 }
 337
 338 #define __ipmr_get_table ipmr_get_table
 339
 340 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 341                            struct mr_table **mrt)
 342 {
 343         *mrt = net->ipv4.mrt;
 344         return 0;
 345 }
 346
 347 static int __net_init ipmr_rules_init(struct net *net)
 348 {
 349         struct mr_table *mrt;
 350
 351         mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 352         if (IS_ERR(mrt))
 353                 return PTR_ERR(mrt);
 354         net->ipv4.mrt = mrt;
 355         return 0;
 356 }
 357
 358 static void __net_exit ipmr_rules_exit(struct net *net)
 359 {
 360         ASSERT_RTNL();
 361         ipmr_free_table(net->ipv4.mrt);
 362         net->ipv4.mrt = NULL;
 363 }
 364
 365 static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
 366                            struct netlink_ext_ack *extack)
 367 {
 368         return 0;
 369 }
 370
 371 static unsigned int ipmr_rules_seq_read(const struct net *net)
 372 {
 373         return 0;
 374 }
 375
 376 bool ipmr_rule_default(const struct fib_rule *rule)
 377 {
 378         return true;
 379 }
 380 EXPORT_SYMBOL(ipmr_rule_default);
 381 #endif
 382
 383 static inline int ipmr_hash_cmp(struct rhashtable_compare_arg *arg,
 384                                 const void *ptr)
 385 {
 386         const struct mfc_cache_cmp_arg *cmparg = arg->key;
 387         const struct mfc_cache *c = ptr;
 388
 389         return cmparg->mfc_mcastgrp != c->mfc_mcastgrp ||
 390                cmparg->mfc_origin != c->mfc_origin;
 391 }
 392
 393 static const struct rhashtable_params ipmr_rht_params = {
 394         .head_offset = offsetof(struct mr_mfc, mnode),
 395         .key_offset = offsetof(struct mfc_cache, cmparg),
 396         .key_len = sizeof(struct mfc_cache_cmp_arg),
 397         .nelem_hint = 3,
 398         .obj_cmpfn = ipmr_hash_cmp,
 399         .automatic_shrinking = true,
 400 };
 401
 402 static void ipmr_new_table_set(struct mr_table *mrt,
 403                                struct net *net)
 404 {
 405 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 406         list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
 407 #endif
 408 }
 409
 410 static struct mfc_cache_cmp_arg ipmr_mr_table_ops_cmparg_any = {
 411         .mfc_mcastgrp = htonl(INADDR_ANY),
 412         .mfc_origin = htonl(INADDR_ANY),
 413 };
 414
 415 static struct mr_table_ops ipmr_mr_table_ops = {
 416         .rht_params = &ipmr_rht_params,
 417         .cmparg_any = &ipmr_mr_table_ops_cmparg_any,
 418 };
 419
 420 static struct mr_table *ipmr_new_table(struct net *net, u32 id)
 421 {
 422         struct mr_table *mrt;
 423
 424         /* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) */
 425         if (id != RT_TABLE_DEFAULT && id >= 1000000000)
 426                 return ERR_PTR(-EINVAL);
 427
 428         mrt = __ipmr_get_table(net, id);
 429         if (mrt)
 430                 return mrt;
 431
 432         return mr_table_alloc(net, id, &ipmr_mr_table_ops,
 433                               ipmr_expire_process, ipmr_new_table_set);
 434 }
 435
 436 static void ipmr_free_table(struct mr_table *mrt)
 437 {
 438         struct net *net = read_pnet(&mrt->net);
 439
 440         WARN_ON_ONCE(!ipmr_can_free_table(net));
 441
 442         timer_shutdown_sync(&mrt->ipmr_expire_timer);
 443         mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC |
 444                                  MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC);
 445         rhltable_destroy(&mrt->mfc_hash);
 446         kfree(mrt);
 447 }
 448
 449 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
 450
 451 /* Initialize ipmr pimreg/tunnel in_device */
 452 static bool ipmr_init_vif_indev(const struct net_device *dev)
 453 {
 454         struct in_device *in_dev;
 455
 456         ASSERT_RTNL();
 457
 458         in_dev = __in_dev_get_rtnl(dev);
 459         if (!in_dev)
 460                 return false;
 461         ipv4_devconf_setall(in_dev);
 462         neigh_parms_data_state_setall(in_dev->arp_parms);
 463         IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
 464
 465         return true;
 466 }
 467
 468 static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
 469 {
 470         struct net_device *tunnel_dev, *new_dev;
 471         struct ip_tunnel_parm_kern p = { };
 472         int err;
 473
 474         tunnel_dev = __dev_get_by_name(net, "tunl0");
 475         if (!tunnel_dev)
 476                 goto out;
 477
 478         p.iph.daddr = v->vifc_rmt_addr.s_addr;
 479         p.iph.saddr = v->vifc_lcl_addr.s_addr;
 480         p.iph.version = 4;
 481         p.iph.ihl = 5;
 482         p.iph.protocol = IPPROTO_IPIP;
 483         sprintf(p.name, "dvmrp%d", v->vifc_vifi);
 484
 485         if (!tunnel_dev->netdev_ops->ndo_tunnel_ctl)
 486                 goto out;
 487         err = tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p,
 488                         SIOCADDTUNNEL);
 489         if (err)
 490                 goto out;
 491
 492         new_dev = __dev_get_by_name(net, p.name);
 493         if (!new_dev)
 494                 goto out;
 495
 496         new_dev->flags |= IFF_MULTICAST;
 497         if (!ipmr_init_vif_indev(new_dev))
 498                 goto out_unregister;
 499         if (dev_open(new_dev, NULL))
 500                 goto out_unregister;
 501         dev_hold(new_dev);
 502         err = dev_set_allmulti(new_dev, 1);
 503         if (err) {
 504                 dev_close(new_dev);
 505                 tunnel_dev->netdev_ops->ndo_tunnel_ctl(tunnel_dev, &p,
 506                                 SIOCDELTUNNEL);
 507                 dev_put(new_dev);
 508                 new_dev = ERR_PTR(err);
 509         }
 510         return new_dev;
 511
 512 out_unregister:
 513         unregister_netdevice(new_dev);
 514 out:
 515         return ERR_PTR(-ENOBUFS);
 516 }
 517
 518 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
 519 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
 520 {
 521         struct net *net = dev_net(dev);
 522         struct mr_table *mrt;
 523         struct flowi4 fl4 = {
 524                 .flowi4_oif     = dev->ifindex,
 525                 .flowi4_iif     = skb->skb_iif ? : LOOPBACK_IFINDEX,
 526                 .flowi4_mark    = skb->mark,
 527         };
 528         int err;
 529
 530         err = ipmr_fib_lookup(net, &fl4, &mrt);
 531         if (err < 0) {
 532                 kfree_skb(skb);
 533                 return err;
 534         }
 535
 536         DEV_STATS_ADD(dev, tx_bytes, skb->len);
 537         DEV_STATS_INC(dev, tx_packets);
 538         rcu_read_lock();
 539
 540         /* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */
 541         ipmr_cache_report(mrt, skb, READ_ONCE(mrt->mroute_reg_vif_num),
 542                           IGMPMSG_WHOLEPKT);
 543
 544         rcu_read_unlock();
 545         kfree_skb(skb);
 546         return NETDEV_TX_OK;
 547 }
 548
 549 static int reg_vif_get_iflink(const struct net_device *dev)
 550 {
 551         return 0;
 552 }
 553
 554 static const struct net_device_ops reg_vif_netdev_ops = {
 555         .ndo_start_xmit = reg_vif_xmit,
 556         .ndo_get_iflink = reg_vif_get_iflink,
 557 };
 558
 559 static void reg_vif_setup(struct net_device *dev)
 560 {
 561         dev->type               = ARPHRD_PIMREG;
 562         dev->mtu                = ETH_DATA_LEN - sizeof(struct iphdr) - 8;
 563         dev->flags              = IFF_NOARP;
 564         dev->netdev_ops         = &reg_vif_netdev_ops;
 565         dev->needs_free_netdev  = true;
 566         dev->netns_local        = true;
 567 }
 568
 569 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
 570 {
 571         struct net_device *dev;
 572         char name[IFNAMSIZ];
 573
 574         if (mrt->id == RT_TABLE_DEFAULT)
 575                 sprintf(name, "pimreg");
 576         else
 577                 sprintf(name, "pimreg%u", mrt->id);
 578
 579         dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
 580
 581         if (!dev)
 582                 return NULL;
 583
 584         dev_net_set(dev, net);
 585
 586         if (register_netdevice(dev)) {
 587                 free_netdev(dev);
 588                 return NULL;
 589         }
 590
 591         if (!ipmr_init_vif_indev(dev))
 592                 goto failure;
 593         if (dev_open(dev, NULL))
 594                 goto failure;
 595
 596         dev_hold(dev);
 597
 598         return dev;
 599
 600 failure:
 601         unregister_netdevice(dev);
 602         return NULL;
 603 }
 604
 605 /* called with rcu_read_lock() */
 606 static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
 607                      unsigned int pimlen)
 608 {
 609         struct net_device *reg_dev = NULL;
 610         struct iphdr *encap;
 611         int vif_num;
 612
 613         encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
 614         /* Check that:
 615          * a. packet is really sent to a multicast group
 616          * b. packet is not a NULL-REGISTER
 617          * c. packet is not truncated
 618          */
 619         if (!ipv4_is_multicast(encap->daddr) ||
 620             encap->tot_len == 0 ||
 621             ntohs(encap->tot_len) + pimlen > skb->len)
 622                 return 1;
 623
 624         /* Pairs with WRITE_ONCE() in vif_add()/vid_delete() */
 625         vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
 626         if (vif_num >= 0)
 627                 reg_dev = vif_dev_read(&mrt->vif_table[vif_num]);
 628         if (!reg_dev)
 629                 return 1;
 630
 631         skb->mac_header = skb->network_header;
 632         skb_pull(skb, (u8 *)encap - skb->data);
 633         skb_reset_network_header(skb);
 634         skb->protocol = htons(ETH_P_IP);
 635         skb->ip_summed = CHECKSUM_NONE;
 636
 637         skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
 638
 639         netif_rx(skb);
 640
 641         return NET_RX_SUCCESS;
 642 }
 643 #else
 644 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
 645 {
 646         return NULL;
 647 }
 648 #endif
 649
 650 static int call_ipmr_vif_entry_notifiers(struct net *net,
 651                                          enum fib_event_type event_type,
 652                                          struct vif_device *vif,
 653                                          struct net_device *vif_dev,
 654                                          vifi_t vif_index, u32 tb_id)
 655 {
 656         return mr_call_vif_notifiers(net, RTNL_FAMILY_IPMR, event_type,
 657                                      vif, vif_dev, vif_index, tb_id,
 658                                      &net->ipv4.ipmr_seq);
 659 }
 660
 661 static int call_ipmr_mfc_entry_notifiers(struct net *net,
 662                                          enum fib_event_type event_type,
 663                                          struct mfc_cache *mfc, u32 tb_id)
 664 {
 665         return mr_call_mfc_notifiers(net, RTNL_FAMILY_IPMR, event_type,
 666                                      &mfc->_c, tb_id, &net->ipv4.ipmr_seq);
 667 }
 668
 669 /**
 670  *      vif_delete - Delete a VIF entry
 671  *      @mrt: Table to delete from
 672  *      @vifi: VIF identifier to delete
 673  *      @notify: Set to 1, if the caller is a notifier_call
 674  *      @head: if unregistering the VIF, place it on this queue
 675  */
 676 static int vif_delete(struct mr_table *mrt, int vifi, int notify,
 677                       struct list_head *head)
 678 {
 679         struct net *net = read_pnet(&mrt->net);
 680         struct vif_device *v;
 681         struct net_device *dev;
 682         struct in_device *in_dev;
 683
 684         if (vifi < 0 || vifi >= mrt->maxvif)
 685                 return -EADDRNOTAVAIL;
 686
 687         v = &mrt->vif_table[vifi];
 688
 689         dev = rtnl_dereference(v->dev);
 690         if (!dev)
 691                 return -EADDRNOTAVAIL;
 692
 693         spin_lock(&mrt_lock);
 694         call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_DEL, v, dev,
 695                                       vifi, mrt->id);
 696         RCU_INIT_POINTER(v->dev, NULL);
 697
 698         if (vifi == mrt->mroute_reg_vif_num) {
 699                 /* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */
 700                 WRITE_ONCE(mrt->mroute_reg_vif_num, -1);
 701         }
 702         if (vifi + 1 == mrt->maxvif) {
 703                 int tmp;
 704
 705                 for (tmp = vifi - 1; tmp >= 0; tmp--) {
 706                         if (VIF_EXISTS(mrt, tmp))
 707                                 break;
 708                 }
 709                 WRITE_ONCE(mrt->maxvif, tmp + 1);
 710         }
 711
 712         spin_unlock(&mrt_lock);
 713
 714         dev_set_allmulti(dev, -1);
 715
 716         in_dev = __in_dev_get_rtnl(dev);
 717         if (in_dev) {
 718                 IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
 719                 inet_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
 720                                             NETCONFA_MC_FORWARDING,
 721                                             dev->ifindex, &in_dev->cnf);
 722                 ip_rt_multicast_event(in_dev);
 723         }
 724
 725         if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
 726                 unregister_netdevice_queue(dev, head);
 727
 728         netdev_put(dev, &v->dev_tracker);
 729         return 0;
 730 }
 731
 732 static void ipmr_cache_free_rcu(struct rcu_head *head)
 733 {
 734         struct mr_mfc *c = container_of(head, struct mr_mfc, rcu);
 735
 736         kmem_cache_free(mrt_cachep, (struct mfc_cache *)c);
 737 }
 738
 739 static void ipmr_cache_free(struct mfc_cache *c)
 740 {
 741         call_rcu(&c->_c.rcu, ipmr_cache_free_rcu);
 742 }
 743
 744 /* Destroy an unresolved cache entry, killing queued skbs
 745  * and reporting error to netlink readers.
 746  */
 747 static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
 748 {
 749         struct net *net = read_pnet(&mrt->net);
 750         struct sk_buff *skb;
 751         struct nlmsgerr *e;
 752
 753         atomic_dec(&mrt->cache_resolve_queue_len);
 754
 755         while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved))) {
 756                 if (ip_hdr(skb)->version == 0) {
 757                         struct nlmsghdr *nlh = skb_pull(skb,
 758                                                         sizeof(struct iphdr));
 759                         nlh->nlmsg_type = NLMSG_ERROR;
 760                         nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
 761                         skb_trim(skb, nlh->nlmsg_len);
 762                         e = nlmsg_data(nlh);
 763                         e->error = -ETIMEDOUT;
 764                         memset(&e->msg, 0, sizeof(e->msg));
 765
 766                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
 767                 } else {
 768                         kfree_skb(skb);
 769                 }
 770         }
 771
 772         ipmr_cache_free(c);
 773 }
 774
 775 /* Timer process for the unresolved queue. */
 776 static void ipmr_expire_process(struct timer_list *t)
 777 {
 778         struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
 779         struct mr_mfc *c, *next;
 780         unsigned long expires;
 781         unsigned long now;
 782
 783         if (!spin_trylock(&mfc_unres_lock)) {
 784                 mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10);
 785                 return;
 786         }
 787
 788         if (list_empty(&mrt->mfc_unres_queue))
 789                 goto out;
 790
 791         now = jiffies;
 792         expires = 10*HZ;
 793
 794         list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
 795                 if (time_after(c->mfc_un.unres.expires, now)) {
 796                         unsigned long interval = c->mfc_un.unres.expires - now;
 797                         if (interval < expires)
 798                                 expires = interval;
 799                         continue;
 800                 }
 801
 802                 list_del(&c->list);
 803                 mroute_netlink_event(mrt, (struct mfc_cache *)c, RTM_DELROUTE);
 804                 ipmr_destroy_unres(mrt, (struct mfc_cache *)c);
 805         }
 806
 807         if (!list_empty(&mrt->mfc_unres_queue))
 808                 mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
 809
 810 out:
 811         spin_unlock(&mfc_unres_lock);
 812 }
 813
 814 /* Fill oifs list. It is called under locked mrt_lock. */
 815 static void ipmr_update_thresholds(struct mr_table *mrt, struct mr_mfc *cache,
 816                                    unsigned char *ttls)
 817 {
 818         int vifi;
 819
 820         cache->mfc_un.res.minvif = MAXVIFS;
 821         cache->mfc_un.res.maxvif = 0;
 822         memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
 823
 824         for (vifi = 0; vifi < mrt->maxvif; vifi++) {
 825                 if (VIF_EXISTS(mrt, vifi) &&
 826                     ttls[vifi] && ttls[vifi] < 255) {
 827                         cache->mfc_un.res.ttls[vifi] = ttls[vifi];
 828                         if (cache->mfc_un.res.minvif > vifi)
 829                                 cache->mfc_un.res.minvif = vifi;
 830                         if (cache->mfc_un.res.maxvif <= vifi)
 831                                 cache->mfc_un.res.maxvif = vifi + 1;
 832                 }
 833         }
 834         cache->mfc_un.res.lastuse = jiffies;
 835 }
 836
 837 static int vif_add(struct net *net, struct mr_table *mrt,
 838                    struct vifctl *vifc, int mrtsock)
 839 {
 840         struct netdev_phys_item_id ppid = { };
 841         int vifi = vifc->vifc_vifi;
 842         struct vif_device *v = &mrt->vif_table[vifi];
 843         struct net_device *dev;
 844         struct in_device *in_dev;
 845         int err;
 846
 847         /* Is vif busy ? */
 848         if (VIF_EXISTS(mrt, vifi))
 849                 return -EADDRINUSE;
 850
 851         switch (vifc->vifc_flags) {
 852         case VIFF_REGISTER:
 853                 if (!ipmr_pimsm_enabled())
 854                         return -EINVAL;
 855                 /* Special Purpose VIF in PIM
 856                  * All the packets will be sent to the daemon
 857                  */
 858                 if (mrt->mroute_reg_vif_num >= 0)
 859                         return -EADDRINUSE;
 860                 dev = ipmr_reg_vif(net, mrt);
 861                 if (!dev)
 862                         return -ENOBUFS;
 863                 err = dev_set_allmulti(dev, 1);
 864                 if (err) {
 865                         unregister_netdevice(dev);
 866                         dev_put(dev);
 867                         return err;
 868                 }
 869                 break;
 870         case VIFF_TUNNEL:
 871                 dev = ipmr_new_tunnel(net, vifc);
 872                 if (IS_ERR(dev))
 873                         return PTR_ERR(dev);
 874                 break;
 875         case VIFF_USE_IFINDEX:
 876         case 0:
 877                 if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
 878                         dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
 879                         if (dev && !__in_dev_get_rtnl(dev)) {
 880                                 dev_put(dev);
 881                                 return -EADDRNOTAVAIL;
 882                         }
 883                 } else {
 884                         dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
 885                 }
 886                 if (!dev)
 887                         return -EADDRNOTAVAIL;
 888                 err = dev_set_allmulti(dev, 1);
 889                 if (err) {
 890                         dev_put(dev);
 891                         return err;
 892                 }
 893                 break;
 894         default:
 895                 return -EINVAL;
 896         }
 897
 898         in_dev = __in_dev_get_rtnl(dev);
 899         if (!in_dev) {
 900                 dev_put(dev);
 901                 return -EADDRNOTAVAIL;
 902         }
 903         IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
 904         inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_MC_FORWARDING,
 905                                     dev->ifindex, &in_dev->cnf);
 906         ip_rt_multicast_event(in_dev);
 907
 908         /* Fill in the VIF structures */
 909         vif_device_init(v, dev, vifc->vifc_rate_limit,
 910                         vifc->vifc_threshold,
 911                         vifc->vifc_flags | (!mrtsock ? VIFF_STATIC : 0),
 912                         (VIFF_TUNNEL | VIFF_REGISTER));
 913
 914         err = dev_get_port_parent_id(dev, &ppid, true);
 915         if (err == 0) {
 916                 memcpy(v->dev_parent_id.id, ppid.id, ppid.id_len);
 917                 v->dev_parent_id.id_len = ppid.id_len;
 918         } else {
 919                 v->dev_parent_id.id_len = 0;
 920         }
 921
 922         v->local = vifc->vifc_lcl_addr.s_addr;
 923         v->remote = vifc->vifc_rmt_addr.s_addr;
 924
 925         /* And finish update writing critical data */
 926         spin_lock(&mrt_lock);
 927         rcu_assign_pointer(v->dev, dev);
 928         netdev_tracker_alloc(dev, &v->dev_tracker, GFP_ATOMIC);
 929         if (v->flags & VIFF_REGISTER) {
 930                 /* Pairs with READ_ONCE() in ipmr_cache_report() and reg_vif_xmit() */
 931                 WRITE_ONCE(mrt->mroute_reg_vif_num, vifi);
 932         }
 933         if (vifi+1 > mrt->maxvif)
 934                 WRITE_ONCE(mrt->maxvif, vifi + 1);
 935         spin_unlock(&mrt_lock);
 936         call_ipmr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD, v, dev,
 937                                       vifi, mrt->id);
 938         return 0;
 939 }
 940
 941 /* called with rcu_read_lock() */
 942 static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
 943                                          __be32 origin,
 944                                          __be32 mcastgrp)
 945 {
 946         struct mfc_cache_cmp_arg arg = {
 947                         .mfc_mcastgrp = mcastgrp,
 948                         .mfc_origin = origin
 949         };
 950
 951         return mr_mfc_find(mrt, &arg);
 952 }
 953
 954 /* Look for a (*,G) entry */
 955 static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
 956                                              __be32 mcastgrp, int vifi)
 957 {
 958         struct mfc_cache_cmp_arg arg = {
 959                         .mfc_mcastgrp = mcastgrp,
 960                         .mfc_origin = htonl(INADDR_ANY)
 961         };
 962
 963         if (mcastgrp == htonl(INADDR_ANY))
 964                 return mr_mfc_find_any_parent(mrt, vifi);
 965         return mr_mfc_find_any(mrt, vifi, &arg);
 966 }
 967
 968 /* Look for a (S,G,iif) entry if parent != -1 */
 969 static struct mfc_cache *ipmr_cache_find_parent(struct mr_table *mrt,
 970                                                 __be32 origin, __be32 mcastgrp,
 971                                                 int parent)
 972 {
 973         struct mfc_cache_cmp_arg arg = {
 974                         .mfc_mcastgrp = mcastgrp,
 975                         .mfc_origin = origin,
 976         };
 977
 978         return mr_mfc_find_parent(mrt, &arg, parent);
 979 }
 980
 981 /* Allocate a multicast cache entry */
 982 static struct mfc_cache *ipmr_cache_alloc(void)
 983 {
 984         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
 985
 986         if (c) {
 987                 c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
 988                 c->_c.mfc_un.res.minvif = MAXVIFS;
 989                 c->_c.free = ipmr_cache_free_rcu;
 990                 refcount_set(&c->_c.mfc_un.res.refcount, 1);
 991         }
 992         return c;
 993 }
 994
 995 static struct mfc_cache *ipmr_cache_alloc_unres(void)
 996 {
 997         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
 998
 999         if (c) {
1000                 skb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
1001                 c->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
1002         }
1003         return c;
1004 }
1005
1006 /* A cache entry has gone into a resolved state from queued */
1007 static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
1008                                struct mfc_cache *uc, struct mfc_cache *c)
1009 {
1010         struct sk_buff *skb;
1011         struct nlmsgerr *e;
1012
1013         /* Play the pending entries through our router */
1014         while ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
1015                 if (ip_hdr(skb)->version == 0) {
1016                         struct nlmsghdr *nlh = skb_pull(skb,
1017                                                         sizeof(struct iphdr));
1018
1019                         if (mr_fill_mroute(mrt, skb, &c->_c,
1020                                            nlmsg_data(nlh)) > 0) {
1021                                 nlh->nlmsg_len = skb_tail_pointer(skb) -
1022                                                  (u8 *)nlh;
1023                         } else {
1024                                 nlh->nlmsg_type = NLMSG_ERROR;
1025                                 nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
1026                                 skb_trim(skb, nlh->nlmsg_len);
1027                                 e = nlmsg_data(nlh);
1028                                 e->error = -EMSGSIZE;
1029                                 memset(&e->msg, 0, sizeof(e->msg));
1030                         }
1031
1032                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
1033                 } else {
1034                         rcu_read_lock();
1035                         ip_mr_forward(net, mrt, skb->dev, skb, c, 0);
1036                         rcu_read_unlock();
1037                 }
1038         }
1039 }
1040
1041 /* Bounce a cache query up to mrouted and netlink.
1042  *
1043  * Called under rcu_read_lock().
1044  */
1045 static int ipmr_cache_report(const struct mr_table *mrt,
1046                              struct sk_buff *pkt, vifi_t vifi, int assert)
1047 {
1048         const int ihl = ip_hdrlen(pkt);
1049         struct sock *mroute_sk;
1050         struct igmphdr *igmp;
1051         struct igmpmsg *msg;
1052         struct sk_buff *skb;
1053         int ret;
1054
1055         mroute_sk = rcu_dereference(mrt->mroute_sk);
1056         if (!mroute_sk)
1057                 return -EINVAL;
1058
1059         if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE)
1060                 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
1061         else
1062                 skb = alloc_skb(128, GFP_ATOMIC);
1063
1064         if (!skb)
1065                 return -ENOBUFS;
1066
1067         if (assert == IGMPMSG_WHOLEPKT || assert == IGMPMSG_WRVIFWHOLE) {
1068                 /* Ugly, but we have no choice with this interface.
1069                  * Duplicate old header, fix ihl, length etc.
1070                  * And all this only to mangle msg->im_msgtype and
1071                  * to set msg->im_mbz to "mbz" :-)
1072                  */
1073                 skb_push(skb, sizeof(struct iphdr));
1074                 skb_reset_network_header(skb);
1075                 skb_reset_transport_header(skb);
1076                 msg = (struct igmpmsg *)skb_network_header(skb);
1077                 memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
1078                 msg->im_msgtype = assert;
1079                 msg->im_mbz = 0;
1080                 if (assert == IGMPMSG_WRVIFWHOLE) {
1081                         msg->im_vif = vifi;
1082                         msg->im_vif_hi = vifi >> 8;
1083                 } else {
1084                         /* Pairs with WRITE_ONCE() in vif_add() and vif_delete() */
1085                         int vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
1086
1087                         msg->im_vif = vif_num;
1088                         msg->im_vif_hi = vif_num >> 8;
1089                 }
1090                 ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
1091                 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
1092                                              sizeof(struct iphdr));
1093         } else {
1094                 /* Copy the IP header */
1095                 skb_set_network_header(skb, skb->len);
1096                 skb_put(skb, ihl);
1097                 skb_copy_to_linear_data(skb, pkt->data, ihl);
1098                 /* Flag to the kernel this is a route add */
1099                 ip_hdr(skb)->protocol = 0;
1100                 msg = (struct igmpmsg *)skb_network_header(skb);
1101                 msg->im_vif = vifi;
1102                 msg->im_vif_hi = vifi >> 8;
1103                 ipv4_pktinfo_prepare(mroute_sk, pkt, false);
1104                 memcpy(skb->cb, pkt->cb, sizeof(skb->cb));
1105                 /* Add our header */
1106                 igmp = skb_put(skb, sizeof(struct igmphdr));
1107                 igmp->type = assert;
1108                 msg->im_msgtype = assert;
1109                 igmp->code = 0;
1110                 ip_hdr(skb)->tot_len = htons(skb->len); /* Fix the length */
1111                 skb->transport_header = skb->network_header;
1112         }
1113
1114         igmpmsg_netlink_event(mrt, skb);
1115
1116         /* Deliver to mrouted */
1117         ret = sock_queue_rcv_skb(mroute_sk, skb);
1118
1119         if (ret < 0) {
1120                 net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1121                 kfree_skb(skb);
1122         }
1123
1124         return ret;
1125 }
1126
1127 /* Queue a packet for resolution. It gets locked cache entry! */
1128 /* Called under rcu_read_lock() */
1129 static int ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi,
1130                                  struct sk_buff *skb, struct net_device *dev)
1131 {
1132         const struct iphdr *iph = ip_hdr(skb);
1133         struct mfc_cache *c;
1134         bool found = false;
1135         int err;
1136
1137         spin_lock_bh(&mfc_unres_lock);
1138         list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
1139                 if (c->mfc_mcastgrp == iph->daddr &&
1140                     c->mfc_origin == iph->saddr) {
1141                         found = true;
1142                         break;
1143                 }
1144         }
1145
1146         if (!found) {
1147                 /* Create a new entry if allowable */
1148                 c = ipmr_cache_alloc_unres();
1149                 if (!c) {
1150                         spin_unlock_bh(&mfc_unres_lock);
1151
1152                         kfree_skb(skb);
1153                         return -ENOBUFS;
1154                 }
1155
1156                 /* Fill in the new cache entry */
1157                 c->_c.mfc_parent = -1;
1158                 c->mfc_origin   = iph->saddr;
1159                 c->mfc_mcastgrp = iph->daddr;
1160
1161                 /* Reflect first query at mrouted. */
1162                 err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1163
1164                 if (err < 0) {
1165                         /* If the report failed throw the cache entry
1166                            out - Brad Parker
1167                          */
1168                         spin_unlock_bh(&mfc_unres_lock);
1169
1170                         ipmr_cache_free(c);
1171                         kfree_skb(skb);
1172                         return err;
1173                 }
1174
1175                 atomic_inc(&mrt->cache_resolve_queue_len);
1176                 list_add(&c->_c.list, &mrt->mfc_unres_queue);
1177                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1178
1179                 if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1180                         mod_timer(&mrt->ipmr_expire_timer,
1181                                   c->_c.mfc_un.unres.expires);
1182         }
1183
1184         /* See if we can append the packet */
1185         if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
1186                 kfree_skb(skb);
1187                 err = -ENOBUFS;
1188         } else {
1189                 if (dev) {
1190                         skb->dev = dev;
1191                         skb->skb_iif = dev->ifindex;
1192                 }
1193                 skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
1194                 err = 0;
1195         }
1196
1197         spin_unlock_bh(&mfc_unres_lock);
1198         return err;
1199 }
1200
1201 /* MFC cache manipulation by user space mroute daemon */
1202
1203 static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1204 {
1205         struct net *net = read_pnet(&mrt->net);
1206         struct mfc_cache *c;
1207
1208         /* The entries are added/deleted only under RTNL */
1209         rcu_read_lock();
1210         c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1211                                    mfc->mfcc_mcastgrp.s_addr, parent);
1212         rcu_read_unlock();
1213         if (!c)
1214                 return -ENOENT;
1215         rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ipmr_rht_params);
1216         list_del_rcu(&c->_c.list);
1217         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id);
1218         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1219         mr_cache_put(&c->_c);
1220
1221         return 0;
1222 }
1223
1224 static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1225                         struct mfcctl *mfc, int mrtsock, int parent)
1226 {
1227         struct mfc_cache *uc, *c;
1228         struct mr_mfc *_uc;
1229         bool found;
1230         int ret;
1231
1232         if (mfc->mfcc_parent >= MAXVIFS)
1233                 return -ENFILE;
1234
1235         /* The entries are added/deleted only under RTNL */
1236         rcu_read_lock();
1237         c = ipmr_cache_find_parent(mrt, mfc->mfcc_origin.s_addr,
1238                                    mfc->mfcc_mcastgrp.s_addr, parent);
1239         rcu_read_unlock();
1240         if (c) {
1241                 spin_lock(&mrt_lock);
1242                 c->_c.mfc_parent = mfc->mfcc_parent;
1243                 ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1244                 if (!mrtsock)
1245                         c->_c.mfc_flags |= MFC_STATIC;
1246                 spin_unlock(&mrt_lock);
1247                 call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c,
1248                                               mrt->id);
1249                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1250                 return 0;
1251         }
1252
1253         if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1254             !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1255                 return -EINVAL;
1256
1257         c = ipmr_cache_alloc();
1258         if (!c)
1259                 return -ENOMEM;
1260
1261         c->mfc_origin = mfc->mfcc_origin.s_addr;
1262         c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1263         c->_c.mfc_parent = mfc->mfcc_parent;
1264         ipmr_update_thresholds(mrt, &c->_c, mfc->mfcc_ttls);
1265         if (!mrtsock)
1266                 c->_c.mfc_flags |= MFC_STATIC;
1267
1268         ret = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
1269                                   ipmr_rht_params);
1270         if (ret) {
1271                 pr_err("ipmr: rhtable insert error %d\n", ret);
1272                 ipmr_cache_free(c);
1273                 return ret;
1274         }
1275         list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
1276         /* Check to see if we resolved a queued list. If so we
1277          * need to send on the frames and tidy up.
1278          */
1279         found = false;
1280         spin_lock_bh(&mfc_unres_lock);
1281         list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
1282                 uc = (struct mfc_cache *)_uc;
1283                 if (uc->mfc_origin == c->mfc_origin &&
1284                     uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1285                         list_del(&_uc->list);
1286                         atomic_dec(&mrt->cache_resolve_queue_len);
1287                         found = true;
1288                         break;
1289                 }
1290         }
1291         if (list_empty(&mrt->mfc_unres_queue))
1292                 del_timer(&mrt->ipmr_expire_timer);
1293         spin_unlock_bh(&mfc_unres_lock);
1294
1295         if (found) {
1296                 ipmr_cache_resolve(net, mrt, uc, c);
1297                 ipmr_cache_free(uc);
1298         }
1299         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD, c, mrt->id);
1300         mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1301         return 0;
1302 }
1303
1304 /* Close the multicast socket, and clear the vif tables etc */
1305 static void mroute_clean_tables(struct mr_table *mrt, int flags)
1306 {
1307         struct net *net = read_pnet(&mrt->net);
1308         struct mr_mfc *c, *tmp;
1309         struct mfc_cache *cache;
1310         LIST_HEAD(list);
1311         int i;
1312
1313         /* Shut down all active vif entries */
1314         if (flags & (MRT_FLUSH_VIFS | MRT_FLUSH_VIFS_STATIC)) {
1315                 for (i = 0; i < mrt->maxvif; i++) {
1316                         if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
1317                              !(flags & MRT_FLUSH_VIFS_STATIC)) ||
1318                             (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT_FLUSH_VIFS)))
1319                                 continue;
1320                         vif_delete(mrt, i, 0, &list);
1321                 }
1322                 unregister_netdevice_many(&list);
1323         }
1324
1325         /* Wipe the cache */
1326         if (flags & (MRT_FLUSH_MFC | MRT_FLUSH_MFC_STATIC)) {
1327                 list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
1328                         if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC_STATIC)) ||
1329                             (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT_FLUSH_MFC)))
1330                                 continue;
1331                         rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
1332                         list_del_rcu(&c->list);
1333                         cache = (struct mfc_cache *)c;
1334                         call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
1335                                                       mrt->id);
1336                         mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1337                         mr_cache_put(c);
1338                 }
1339         }
1340
1341         if (flags & MRT_FLUSH_MFC) {
1342                 if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1343                         spin_lock_bh(&mfc_unres_lock);
1344                         list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
1345                                 list_del(&c->list);
1346                                 cache = (struct mfc_cache *)c;
1347                                 mroute_netlink_event(mrt, cache, RTM_DELROUTE);
1348                                 ipmr_destroy_unres(mrt, cache);
1349                         }
1350                         spin_unlock_bh(&mfc_unres_lock);
1351                 }
1352         }
1353 }
1354
1355 /* called from ip_ra_control(), before an RCU grace period,
1356  * we don't need to call synchronize_rcu() here
1357  */
1358 static void mrtsock_destruct(struct sock *sk)
1359 {
1360         struct net *net = sock_net(sk);
1361         struct mr_table *mrt;
1362
1363         rtnl_lock();
1364         ipmr_for_each_table(mrt, net) {
1365                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1366                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1367                         inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1368                                                     NETCONFA_MC_FORWARDING,
1369                                                     NETCONFA_IFINDEX_ALL,
1370                                                     net->ipv4.devconf_all);
1371                         RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1372                         mroute_clean_tables(mrt, MRT_FLUSH_VIFS | MRT_FLUSH_MFC);
1373                 }
1374         }
1375         rtnl_unlock();
1376 }
1377
1378 /* Socket options and virtual interface manipulation. The whole
1379  * virtual interface system is a complete heap, but unfortunately
1380  * that's how BSD mrouted happens to think. Maybe one day with a proper
1381  * MOSPF/PIM router set up we can clean this up.
1382  */
1383
1384 int ip_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval,
1385                          unsigned int optlen)
1386 {
1387         struct net *net = sock_net(sk);
1388         int val, ret = 0, parent = 0;
1389         struct mr_table *mrt;
1390         struct vifctl vif;
1391         struct mfcctl mfc;
1392         bool do_wrvifwhole;
1393         u32 uval;
1394
1395         /* There's one exception to the lock - MRT_DONE which needs to unlock */
1396         rtnl_lock();
1397         if (sk->sk_type != SOCK_RAW ||
1398             inet_sk(sk)->inet_num != IPPROTO_IGMP) {
1399                 ret = -EOPNOTSUPP;
1400                 goto out_unlock;
1401         }
1402
1403         mrt = __ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1404         if (!mrt) {
1405                 ret = -ENOENT;
1406                 goto out_unlock;
1407         }
1408         if (optname != MRT_INIT) {
1409                 if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1410                     !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
1411                         ret = -EACCES;
1412                         goto out_unlock;
1413                 }
1414         }
1415
1416         switch (optname) {
1417         case MRT_INIT:
1418                 if (optlen != sizeof(int)) {
1419                         ret = -EINVAL;
1420                         break;
1421                 }
1422                 if (rtnl_dereference(mrt->mroute_sk)) {
1423                         ret = -EADDRINUSE;
1424                         break;
1425                 }
1426
1427                 ret = ip_ra_control(sk, 1, mrtsock_destruct);
1428                 if (ret == 0) {
1429                         rcu_assign_pointer(mrt->mroute_sk, sk);
1430                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1431                         inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
1432                                                     NETCONFA_MC_FORWARDING,
1433                                                     NETCONFA_IFINDEX_ALL,
1434                                                     net->ipv4.devconf_all);
1435                 }
1436                 break;
1437         case MRT_DONE:
1438                 if (sk != rcu_access_pointer(mrt->mroute_sk)) {
1439                         ret = -EACCES;
1440                 } else {
1441                         /* We need to unlock here because mrtsock_destruct takes
1442                          * care of rtnl itself and we can't change that due to
1443                          * the IP_ROUTER_ALERT setsockopt which runs without it.
1444                          */
1445                         rtnl_unlock();
1446                         ret = ip_ra_control(sk, 0, NULL);
1447                         goto out;
1448                 }
1449                 break;
1450         case MRT_ADD_VIF:
1451         case MRT_DEL_VIF:
1452                 if (optlen != sizeof(vif)) {
1453                         ret = -EINVAL;
1454                         break;
1455                 }
1456                 if (copy_from_sockptr(&vif, optval, sizeof(vif))) {
1457                         ret = -EFAULT;
1458                         break;
1459                 }
1460                 if (vif.vifc_vifi >= MAXVIFS) {
1461                         ret = -ENFILE;
1462                         break;
1463                 }
1464                 if (optname == MRT_ADD_VIF) {
1465                         ret = vif_add(net, mrt, &vif,
1466                                       sk == rtnl_dereference(mrt->mroute_sk));
1467                 } else {
1468                         ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1469                 }
1470                 break;
1471         /* Manipulate the forwarding caches. These live
1472          * in a sort of kernel/user symbiosis.
1473          */
1474         case MRT_ADD_MFC:
1475         case MRT_DEL_MFC:
1476                 parent = -1;
1477                 fallthrough;
1478         case MRT_ADD_MFC_PROXY:
1479         case MRT_DEL_MFC_PROXY:
1480                 if (optlen != sizeof(mfc)) {
1481                         ret = -EINVAL;
1482                         break;
1483                 }
1484                 if (copy_from_sockptr(&mfc, optval, sizeof(mfc))) {
1485                         ret = -EFAULT;
1486                         break;
1487                 }
1488                 if (parent == 0)
1489                         parent = mfc.mfcc_parent;
1490                 if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1491                         ret = ipmr_mfc_delete(mrt, &mfc, parent);
1492                 else
1493                         ret = ipmr_mfc_add(net, mrt, &mfc,
1494                                            sk == rtnl_dereference(mrt->mroute_sk),
1495                                            parent);
1496                 break;
1497         case MRT_FLUSH:
1498                 if (optlen != sizeof(val)) {
1499                         ret = -EINVAL;
1500                         break;
1501                 }
1502                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1503                         ret = -EFAULT;
1504                         break;
1505                 }
1506                 mroute_clean_tables(mrt, val);
1507                 break;
1508         /* Control PIM assert. */
1509         case MRT_ASSERT:
1510                 if (optlen != sizeof(val)) {
1511                         ret = -EINVAL;
1512                         break;
1513                 }
1514                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1515                         ret = -EFAULT;
1516                         break;
1517                 }
1518                 mrt->mroute_do_assert = val;
1519                 break;
1520         case MRT_PIM:
1521                 if (!ipmr_pimsm_enabled()) {
1522                         ret = -ENOPROTOOPT;
1523                         break;
1524                 }
1525                 if (optlen != sizeof(val)) {
1526                         ret = -EINVAL;
1527                         break;
1528                 }
1529                 if (copy_from_sockptr(&val, optval, sizeof(val))) {
1530                         ret = -EFAULT;
1531                         break;
1532                 }
1533
1534                 do_wrvifwhole = (val == IGMPMSG_WRVIFWHOLE);
1535                 val = !!val;
1536                 if (val != mrt->mroute_do_pim) {
1537                         mrt->mroute_do_pim = val;
1538                         mrt->mroute_do_assert = val;
1539                         mrt->mroute_do_wrvifwhole = do_wrvifwhole;
1540                 }
1541                 break;
1542         case MRT_TABLE:
1543                 if (!IS_BUILTIN(CONFIG_IP_MROUTE_MULTIPLE_TABLES)) {
1544                         ret = -ENOPROTOOPT;
1545                         break;
1546                 }
1547                 if (optlen != sizeof(uval)) {
1548                         ret = -EINVAL;
1549                         break;
1550                 }
1551                 if (copy_from_sockptr(&uval, optval, sizeof(uval))) {
1552                         ret = -EFAULT;
1553                         break;
1554                 }
1555
1556                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1557                         ret = -EBUSY;
1558                 } else {
1559                         mrt = ipmr_new_table(net, uval);
1560                         if (IS_ERR(mrt))
1561                                 ret = PTR_ERR(mrt);
1562                         else
1563                                 raw_sk(sk)->ipmr_table = uval;
1564                 }
1565                 break;
1566         /* Spurious command, or MRT_VERSION which you cannot set. */
1567         default:
1568                 ret = -ENOPROTOOPT;
1569         }
1570 out_unlock:
1571         rtnl_unlock();
1572 out:
1573         return ret;
1574 }
1575
1576 /* Execute if this ioctl is a special mroute ioctl */
1577 int ipmr_sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1578 {
1579         switch (cmd) {
1580         /* These userspace buffers will be consumed by ipmr_ioctl() */
1581         case SIOCGETVIFCNT: {
1582                 struct sioc_vif_req buffer;
1583
1584                 return sock_ioctl_inout(sk, cmd, arg, &buffer,
1585                                       sizeof(buffer));
1586                 }
1587         case SIOCGETSGCNT: {
1588                 struct sioc_sg_req buffer;
1589
1590                 return sock_ioctl_inout(sk, cmd, arg, &buffer,
1591                                       sizeof(buffer));
1592                 }
1593         }
1594         /* return code > 0 means that the ioctl was not executed */
1595         return 1;
1596 }
1597
1598 /* Getsock opt support for the multicast routing system. */
1599 int ip_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval,
1600                          sockptr_t optlen)
1601 {
1602         int olr;
1603         int val;
1604         struct net *net = sock_net(sk);
1605         struct mr_table *mrt;
1606
1607         if (sk->sk_type != SOCK_RAW ||
1608             inet_sk(sk)->inet_num != IPPROTO_IGMP)
1609                 return -EOPNOTSUPP;
1610
1611         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1612         if (!mrt)
1613                 return -ENOENT;
1614
1615         switch (optname) {
1616         case MRT_VERSION:
1617                 val = 0x0305;
1618                 break;
1619         case MRT_PIM:
1620                 if (!ipmr_pimsm_enabled())
1621                         return -ENOPROTOOPT;
1622                 val = mrt->mroute_do_pim;
1623                 break;
1624         case MRT_ASSERT:
1625                 val = mrt->mroute_do_assert;
1626                 break;
1627         default:
1628                 return -ENOPROTOOPT;
1629         }
1630
1631         if (copy_from_sockptr(&olr, optlen, sizeof(int)))
1632                 return -EFAULT;
1633         if (olr < 0)
1634                 return -EINVAL;
1635
1636         olr = min_t(unsigned int, olr, sizeof(int));
1637
1638         if (copy_to_sockptr(optlen, &olr, sizeof(int)))
1639                 return -EFAULT;
1640         if (copy_to_sockptr(optval, &val, olr))
1641                 return -EFAULT;
1642         return 0;
1643 }
1644
1645 /* The IP multicast ioctl support routines. */
1646 int ipmr_ioctl(struct sock *sk, int cmd, void *arg)
1647 {
1648         struct vif_device *vif;
1649         struct mfc_cache *c;
1650         struct net *net = sock_net(sk);
1651         struct sioc_vif_req *vr;
1652         struct sioc_sg_req *sr;
1653         struct mr_table *mrt;
1654
1655         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1656         if (!mrt)
1657                 return -ENOENT;
1658
1659         switch (cmd) {
1660         case SIOCGETVIFCNT:
1661                 vr = (struct sioc_vif_req *)arg;
1662                 if (vr->vifi >= mrt->maxvif)
1663                         return -EINVAL;
1664                 vr->vifi = array_index_nospec(vr->vifi, mrt->maxvif);
1665                 rcu_read_lock();
1666                 vif = &mrt->vif_table[vr->vifi];
1667                 if (VIF_EXISTS(mrt, vr->vifi)) {
1668                         vr->icount = READ_ONCE(vif->pkt_in);
1669                         vr->ocount = READ_ONCE(vif->pkt_out);
1670                         vr->ibytes = READ_ONCE(vif->bytes_in);
1671                         vr->obytes = READ_ONCE(vif->bytes_out);
1672                         rcu_read_unlock();
1673
1674                         return 0;
1675                 }
1676                 rcu_read_unlock();
1677                 return -EADDRNOTAVAIL;
1678         case SIOCGETSGCNT:
1679                 sr = (struct sioc_sg_req *)arg;
1680
1681                 rcu_read_lock();
1682                 c = ipmr_cache_find(mrt, sr->src.s_addr, sr->grp.s_addr);
1683                 if (c) {
1684                         sr->pktcnt = c->_c.mfc_un.res.pkt;
1685                         sr->bytecnt = c->_c.mfc_un.res.bytes;
1686                         sr->wrong_if = c->_c.mfc_un.res.wrong_if;
1687                         rcu_read_unlock();
1688                         return 0;
1689                 }
1690                 rcu_read_unlock();
1691                 return -EADDRNOTAVAIL;
1692         default:
1693                 return -ENOIOCTLCMD;
1694         }
1695 }
1696
1697 #ifdef CONFIG_COMPAT
1698 struct compat_sioc_sg_req {
1699         struct in_addr src;
1700         struct in_addr grp;
1701         compat_ulong_t pktcnt;
1702         compat_ulong_t bytecnt;
1703         compat_ulong_t wrong_if;
1704 };
1705
1706 struct compat_sioc_vif_req {
1707         vifi_t  vifi;           /* Which iface */
1708         compat_ulong_t icount;
1709         compat_ulong_t ocount;
1710         compat_ulong_t ibytes;
1711         compat_ulong_t obytes;
1712 };
1713
1714 int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1715 {
1716         struct compat_sioc_sg_req sr;
1717         struct compat_sioc_vif_req vr;
1718         struct vif_device *vif;
1719         struct mfc_cache *c;
1720         struct net *net = sock_net(sk);
1721         struct mr_table *mrt;
1722
1723         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1724         if (!mrt)
1725                 return -ENOENT;
1726
1727         switch (cmd) {
1728         case SIOCGETVIFCNT:
1729                 if (copy_from_user(&vr, arg, sizeof(vr)))
1730                         return -EFAULT;
1731                 if (vr.vifi >= mrt->maxvif)
1732                         return -EINVAL;
1733                 vr.vifi = array_index_nospec(vr.vifi, mrt->maxvif);
1734                 rcu_read_lock();
1735                 vif = &mrt->vif_table[vr.vifi];
1736                 if (VIF_EXISTS(mrt, vr.vifi)) {
1737                         vr.icount = READ_ONCE(vif->pkt_in);
1738                         vr.ocount = READ_ONCE(vif->pkt_out);
1739                         vr.ibytes = READ_ONCE(vif->bytes_in);
1740                         vr.obytes = READ_ONCE(vif->bytes_out);
1741                         rcu_read_unlock();
1742
1743                         if (copy_to_user(arg, &vr, sizeof(vr)))
1744                                 return -EFAULT;
1745                         return 0;
1746                 }
1747                 rcu_read_unlock();
1748                 return -EADDRNOTAVAIL;
1749         case SIOCGETSGCNT:
1750                 if (copy_from_user(&sr, arg, sizeof(sr)))
1751                         return -EFAULT;
1752
1753                 rcu_read_lock();
1754                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1755                 if (c) {
1756                         sr.pktcnt = c->_c.mfc_un.res.pkt;
1757                         sr.bytecnt = c->_c.mfc_un.res.bytes;
1758                         sr.wrong_if = c->_c.mfc_un.res.wrong_if;
1759                         rcu_read_unlock();
1760
1761                         if (copy_to_user(arg, &sr, sizeof(sr)))
1762                                 return -EFAULT;
1763                         return 0;
1764                 }
1765                 rcu_read_unlock();
1766                 return -EADDRNOTAVAIL;
1767         default:
1768                 return -ENOIOCTLCMD;
1769         }
1770 }
1771 #endif
1772
1773 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1774 {
1775         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1776         struct net *net = dev_net(dev);
1777         struct mr_table *mrt;
1778         struct vif_device *v;
1779         int ct;
1780
1781         if (event != NETDEV_UNREGISTER)
1782                 return NOTIFY_DONE;
1783
1784         ipmr_for_each_table(mrt, net) {
1785                 v = &mrt->vif_table[0];
1786                 for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1787                         if (rcu_access_pointer(v->dev) == dev)
1788                                 vif_delete(mrt, ct, 1, NULL);
1789                 }
1790         }
1791         return NOTIFY_DONE;
1792 }
1793
1794 static struct notifier_block ip_mr_notifier = {
1795         .notifier_call = ipmr_device_event,
1796 };
1797
1798 /* Encapsulate a packet by attaching a valid IPIP header to it.
1799  * This avoids tunnel drivers and other mess and gives us the speed so
1800  * important for multicast video.
1801  */
1802 static void ip_encap(struct net *net, struct sk_buff *skb,
1803                      __be32 saddr, __be32 daddr)
1804 {
1805         struct iphdr *iph;
1806         const struct iphdr *old_iph = ip_hdr(skb);
1807
1808         skb_push(skb, sizeof(struct iphdr));
1809         skb->transport_header = skb->network_header;
1810         skb_reset_network_header(skb);
1811         iph = ip_hdr(skb);
1812
1813         iph->version    =       4;
1814         iph->tos        =       old_iph->tos;
1815         iph->ttl        =       old_iph->ttl;
1816         iph->frag_off   =       0;
1817         iph->daddr      =       daddr;
1818         iph->saddr      =       saddr;
1819         iph->protocol   =       IPPROTO_IPIP;
1820         iph->ihl        =       5;
1821         iph->tot_len    =       htons(skb->len);
1822         ip_select_ident(net, skb, NULL);
1823         ip_send_check(iph);
1824
1825         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1826         nf_reset_ct(skb);
1827 }
1828
1829 static inline int ipmr_forward_finish(struct net *net, struct sock *sk,
1830                                       struct sk_buff *skb)
1831 {
1832         struct ip_options *opt = &(IPCB(skb)->opt);
1833
1834         IP_INC_STATS(net, IPSTATS_MIB_OUTFORWDATAGRAMS);
1835
1836         if (unlikely(opt->optlen))
1837                 ip_forward_options(skb);
1838
1839         return dst_output(net, sk, skb);
1840 }
1841
1842 #ifdef CONFIG_NET_SWITCHDEV
1843 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1844                                    int in_vifi, int out_vifi)
1845 {
1846         struct vif_device *out_vif = &mrt->vif_table[out_vifi];
1847         struct vif_device *in_vif = &mrt->vif_table[in_vifi];
1848
1849         if (!skb->offload_l3_fwd_mark)
1850                 return false;
1851         if (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
1852                 return false;
1853         return netdev_phys_item_id_same(&out_vif->dev_parent_id,
1854                                         &in_vif->dev_parent_id);
1855 }
1856 #else
1857 static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
1858                                    int in_vifi, int out_vifi)
1859 {
1860         return false;
1861 }
1862 #endif
1863
1864 /* Processing handlers for ipmr_forward, under rcu_read_lock() */
1865
1866 static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1867                             int in_vifi, struct sk_buff *skb, int vifi)
1868 {
1869         const struct iphdr *iph = ip_hdr(skb);
1870         struct vif_device *vif = &mrt->vif_table[vifi];
1871         struct net_device *vif_dev;
1872         struct net_device *dev;
1873         struct rtable *rt;
1874         struct flowi4 fl4;
1875         int    encap = 0;
1876
1877         vif_dev = vif_dev_read(vif);
1878         if (!vif_dev)
1879                 goto out_free;
1880
1881         if (vif->flags & VIFF_REGISTER) {
1882                 WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1883                 WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1884                 DEV_STATS_ADD(vif_dev, tx_bytes, skb->len);
1885                 DEV_STATS_INC(vif_dev, tx_packets);
1886                 ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1887                 goto out_free;
1888         }
1889
1890         if (ipmr_forward_offloaded(skb, mrt, in_vifi, vifi))
1891                 goto out_free;
1892
1893         if (vif->flags & VIFF_TUNNEL) {
1894                 rt = ip_route_output_ports(net, &fl4, NULL,
1895                                            vif->remote, vif->local,
1896                                            0, 0,
1897                                            IPPROTO_IPIP,
1898                                            iph->tos & INET_DSCP_MASK, vif->link);
1899                 if (IS_ERR(rt))
1900                         goto out_free;
1901                 encap = sizeof(struct iphdr);
1902         } else {
1903                 rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1904                                            0, 0,
1905                                            IPPROTO_IPIP,
1906                                            iph->tos & INET_DSCP_MASK, vif->link);
1907                 if (IS_ERR(rt))
1908                         goto out_free;
1909         }
1910
1911         dev = rt->dst.dev;
1912
1913         if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1914                 /* Do not fragment multicasts. Alas, IPv4 does not
1915                  * allow to send ICMP, so that packets will disappear
1916                  * to blackhole.
1917                  */
1918                 IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);
1919                 ip_rt_put(rt);
1920                 goto out_free;
1921         }
1922
1923         encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1924
1925         if (skb_cow(skb, encap)) {
1926                 ip_rt_put(rt);
1927                 goto out_free;
1928         }
1929
1930         WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
1931         WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
1932
1933         skb_dst_drop(skb);
1934         skb_dst_set(skb, &rt->dst);
1935         ip_decrease_ttl(ip_hdr(skb));
1936
1937         /* FIXME: forward and output firewalls used to be called here.
1938          * What do we do with netfilter? -- RR
1939          */
1940         if (vif->flags & VIFF_TUNNEL) {
1941                 ip_encap(net, skb, vif->local, vif->remote);
1942                 /* FIXME: extra output firewall step used to be here. --RR */
1943                 DEV_STATS_INC(vif_dev, tx_packets);
1944                 DEV_STATS_ADD(vif_dev, tx_bytes, skb->len);
1945         }
1946
1947         IPCB(skb)->flags |= IPSKB_FORWARDED;
1948
1949         /* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1950          * not only before forwarding, but after forwarding on all output
1951          * interfaces. It is clear, if mrouter runs a multicasting
1952          * program, it should receive packets not depending to what interface
1953          * program is joined.
1954          * If we will not make it, the program will have to join on all
1955          * interfaces. On the other hand, multihoming host (or router, but
1956          * not mrouter) cannot join to more than one interface - it will
1957          * result in receiving multiple packets.
1958          */
1959         NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD,
1960                 net, NULL, skb, skb->dev, dev,
1961                 ipmr_forward_finish);
1962         return;
1963
1964 out_free:
1965         kfree_skb(skb);
1966 }
1967
1968 /* Called with mrt_lock or rcu_read_lock() */
1969 static int ipmr_find_vif(const struct mr_table *mrt, struct net_device *dev)
1970 {
1971         int ct;
1972         /* Pairs with WRITE_ONCE() in vif_delete()/vif_add() */
1973         for (ct = READ_ONCE(mrt->maxvif) - 1; ct >= 0; ct--) {
1974                 if (rcu_access_pointer(mrt->vif_table[ct].dev) == dev)
1975                         break;
1976         }
1977         return ct;
1978 }
1979
1980 /* "local" means that we should preserve one skb (for local delivery) */
1981 /* Called uner rcu_read_lock() */
1982 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1983                           struct net_device *dev, struct sk_buff *skb,
1984                           struct mfc_cache *c, int local)
1985 {
1986         int true_vifi = ipmr_find_vif(mrt, dev);
1987         int psend = -1;
1988         int vif, ct;
1989
1990         vif = c->_c.mfc_parent;
1991         c->_c.mfc_un.res.pkt++;
1992         c->_c.mfc_un.res.bytes += skb->len;
1993         c->_c.mfc_un.res.lastuse = jiffies;
1994
1995         if (c->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1996                 struct mfc_cache *cache_proxy;
1997
1998                 /* For an (*,G) entry, we only check that the incoming
1999                  * interface is part of the static tree.
2000                  */
2001                 cache_proxy = mr_mfc_find_any_parent(mrt, vif);
2002                 if (cache_proxy &&
2003                     cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
2004                         goto forward;
2005         }
2006
2007         /* Wrong interface: drop packet and (maybe) send PIM assert. */
2008         if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) {
2009                 if (rt_is_output_route(skb_rtable(skb))) {
2010                         /* It is our own packet, looped back.
2011                          * Very complicated situation...
2012                          *
2013                          * The best workaround until routing daemons will be
2014                          * fixed is not to redistribute packet, if it was
2015                          * send through wrong interface. It means, that
2016                          * multicast applications WILL NOT work for
2017                          * (S,G), which have default multicast route pointing
2018                          * to wrong oif. In any case, it is not a good
2019                          * idea to use multicasting applications on router.
2020                          */
2021                         goto dont_forward;
2022                 }
2023
2024                 c->_c.mfc_un.res.wrong_if++;
2025
2026                 if (true_vifi >= 0 && mrt->mroute_do_assert &&
2027                     /* pimsm uses asserts, when switching from RPT to SPT,
2028                      * so that we cannot check that packet arrived on an oif.
2029                      * It is bad, but otherwise we would need to move pretty
2030                      * large chunk of pimd to kernel. Ough... --ANK
2031                      */
2032                     (mrt->mroute_do_pim ||
2033                      c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
2034                     time_after(jiffies,
2035                                c->_c.mfc_un.res.last_assert +
2036                                MFC_ASSERT_THRESH)) {
2037                         c->_c.mfc_un.res.last_assert = jiffies;
2038                         ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
2039                         if (mrt->mroute_do_wrvifwhole)
2040                                 ipmr_cache_report(mrt, skb, true_vifi,
2041                                                   IGMPMSG_WRVIFWHOLE);
2042                 }
2043                 goto dont_forward;
2044         }
2045
2046 forward:
2047         WRITE_ONCE(mrt->vif_table[vif].pkt_in,
2048                    mrt->vif_table[vif].pkt_in + 1);
2049         WRITE_ONCE(mrt->vif_table[vif].bytes_in,
2050                    mrt->vif_table[vif].bytes_in + skb->len);
2051
2052         /* Forward the frame */
2053         if (c->mfc_origin == htonl(INADDR_ANY) &&
2054             c->mfc_mcastgrp == htonl(INADDR_ANY)) {
2055                 if (true_vifi >= 0 &&
2056                     true_vifi != c->_c.mfc_parent &&
2057                     ip_hdr(skb)->ttl >
2058                                 c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
2059                         /* It's an (*,*) entry and the packet is not coming from
2060                          * the upstream: forward the packet to the upstream
2061                          * only.
2062                          */
2063                         psend = c->_c.mfc_parent;
2064                         goto last_forward;
2065                 }
2066                 goto dont_forward;
2067         }
2068         for (ct = c->_c.mfc_un.res.maxvif - 1;
2069              ct >= c->_c.mfc_un.res.minvif; ct--) {
2070                 /* For (*,G) entry, don't forward to the incoming interface */
2071                 if ((c->mfc_origin != htonl(INADDR_ANY) ||
2072                      ct != true_vifi) &&
2073                     ip_hdr(skb)->ttl > c->_c.mfc_un.res.ttls[ct]) {
2074                         if (psend != -1) {
2075                                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2076
2077                                 if (skb2)
2078                                         ipmr_queue_xmit(net, mrt, true_vifi,
2079                                                         skb2, psend);
2080                         }
2081                         psend = ct;
2082                 }
2083         }
2084 last_forward:
2085         if (psend != -1) {
2086                 if (local) {
2087                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2088
2089                         if (skb2)
2090                                 ipmr_queue_xmit(net, mrt, true_vifi, skb2,
2091                                                 psend);
2092                 } else {
2093                         ipmr_queue_xmit(net, mrt, true_vifi, skb, psend);
2094                         return;
2095                 }
2096         }
2097
2098 dont_forward:
2099         if (!local)
2100                 kfree_skb(skb);
2101 }
2102
2103 static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
2104 {
2105         struct rtable *rt = skb_rtable(skb);
2106         struct iphdr *iph = ip_hdr(skb);
2107         struct flowi4 fl4 = {
2108                 .daddr = iph->daddr,
2109                 .saddr = iph->saddr,
2110                 .flowi4_tos = inet_dscp_to_dsfield(ip4h_dscp(iph)),
2111                 .flowi4_oif = (rt_is_output_route(rt) ?
2112                                skb->dev->ifindex : 0),
2113                 .flowi4_iif = (rt_is_output_route(rt) ?
2114                                LOOPBACK_IFINDEX :
2115                                skb->dev->ifindex),
2116                 .flowi4_mark = skb->mark,
2117         };
2118         struct mr_table *mrt;
2119         int err;
2120
2121         err = ipmr_fib_lookup(net, &fl4, &mrt);
2122         if (err)
2123                 return ERR_PTR(err);
2124         return mrt;
2125 }
2126
2127 /* Multicast packets for forwarding arrive here
2128  * Called with rcu_read_lock();
2129  */
2130 int ip_mr_input(struct sk_buff *skb)
2131 {
2132         struct mfc_cache *cache;
2133         struct net *net = dev_net(skb->dev);
2134         int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
2135         struct mr_table *mrt;
2136         struct net_device *dev;
2137
2138         /* skb->dev passed in is the loX master dev for vrfs.
2139          * As there are no vifs associated with loopback devices,
2140          * get the proper interface that does have a vif associated with it.
2141          */
2142         dev = skb->dev;
2143         if (netif_is_l3_master(skb->dev)) {
2144                 dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
2145                 if (!dev) {
2146                         kfree_skb(skb);
2147                         return -ENODEV;
2148                 }
2149         }
2150
2151         /* Packet is looped back after forward, it should not be
2152          * forwarded second time, but still can be delivered locally.
2153          */
2154         if (IPCB(skb)->flags & IPSKB_FORWARDED)
2155                 goto dont_forward;
2156
2157         mrt = ipmr_rt_fib_lookup(net, skb);
2158         if (IS_ERR(mrt)) {
2159                 kfree_skb(skb);
2160                 return PTR_ERR(mrt);
2161         }
2162         if (!local) {
2163                 if (IPCB(skb)->opt.router_alert) {
2164                         if (ip_call_ra_chain(skb))
2165                                 return 0;
2166                 } else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
2167                         /* IGMPv1 (and broken IGMPv2 implementations sort of
2168                          * Cisco IOS <= 11.2(8)) do not put router alert
2169                          * option to IGMP packets destined to routable
2170                          * groups. It is very bad, because it means
2171                          * that we can forward NO IGMP messages.
2172                          */
2173                         struct sock *mroute_sk;
2174
2175                         mroute_sk = rcu_dereference(mrt->mroute_sk);
2176                         if (mroute_sk) {
2177                                 nf_reset_ct(skb);
2178                                 raw_rcv(mroute_sk, skb);
2179                                 return 0;
2180                         }
2181                 }
2182         }
2183
2184         /* already under rcu_read_lock() */
2185         cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
2186         if (!cache) {
2187                 int vif = ipmr_find_vif(mrt, dev);
2188
2189                 if (vif >= 0)
2190                         cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
2191                                                     vif);
2192         }
2193
2194         /* No usable cache entry */
2195         if (!cache) {
2196                 int vif;
2197
2198                 if (local) {
2199                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2200                         ip_local_deliver(skb);
2201                         if (!skb2)
2202                                 return -ENOBUFS;
2203                         skb = skb2;
2204                 }
2205
2206                 vif = ipmr_find_vif(mrt, dev);
2207                 if (vif >= 0)
2208                         return ipmr_cache_unresolved(mrt, vif, skb, dev);
2209                 kfree_skb(skb);
2210                 return -ENODEV;
2211         }
2212
2213         ip_mr_forward(net, mrt, dev, skb, cache, local);
2214
2215         if (local)
2216                 return ip_local_deliver(skb);
2217
2218         return 0;
2219
2220 dont_forward:
2221         if (local)
2222                 return ip_local_deliver(skb);
2223         kfree_skb(skb);
2224         return 0;
2225 }
2226
2227 #ifdef CONFIG_IP_PIMSM_V1
2228 /* Handle IGMP messages of PIMv1 */
2229 int pim_rcv_v1(struct sk_buff *skb)
2230 {
2231         struct igmphdr *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 = igmp_hdr(skb);
2239
2240         mrt = ipmr_rt_fib_lookup(net, skb);
2241         if (IS_ERR(mrt))
2242                 goto drop;
2243         if (!mrt->mroute_do_pim ||
2244             pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
2245                 goto drop;
2246
2247         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2248 drop:
2249                 kfree_skb(skb);
2250         }
2251         return 0;
2252 }
2253 #endif
2254
2255 #ifdef CONFIG_IP_PIMSM_V2
2256 static int pim_rcv(struct sk_buff *skb)
2257 {
2258         struct pimreghdr *pim;
2259         struct net *net = dev_net(skb->dev);
2260         struct mr_table *mrt;
2261
2262         if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2263                 goto drop;
2264
2265         pim = (struct pimreghdr *)skb_transport_header(skb);
2266         if (pim->type != ((PIM_VERSION << 4) | (PIM_TYPE_REGISTER)) ||
2267             (pim->flags & PIM_NULL_REGISTER) ||
2268             (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
2269              csum_fold(skb_checksum(skb, 0, skb->len, 0))))
2270                 goto drop;
2271
2272         mrt = ipmr_rt_fib_lookup(net, skb);
2273         if (IS_ERR(mrt))
2274                 goto drop;
2275         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2276 drop:
2277                 kfree_skb(skb);
2278         }
2279         return 0;
2280 }
2281 #endif
2282
2283 int ipmr_get_route(struct net *net, struct sk_buff *skb,
2284                    __be32 saddr, __be32 daddr,
2285                    struct rtmsg *rtm, u32 portid)
2286 {
2287         struct mfc_cache *cache;
2288         struct mr_table *mrt;
2289         int err;
2290
2291         rcu_read_lock();
2292         mrt = __ipmr_get_table(net, RT_TABLE_DEFAULT);
2293         if (!mrt) {
2294                 rcu_read_unlock();
2295                 return -ENOENT;
2296         }
2297
2298         cache = ipmr_cache_find(mrt, saddr, daddr);
2299         if (!cache && skb->dev) {
2300                 int vif = ipmr_find_vif(mrt, skb->dev);
2301
2302                 if (vif >= 0)
2303                         cache = ipmr_cache_find_any(mrt, daddr, vif);
2304         }
2305         if (!cache) {
2306                 struct sk_buff *skb2;
2307                 struct iphdr *iph;
2308                 struct net_device *dev;
2309                 int vif = -1;
2310
2311                 dev = skb->dev;
2312                 if (dev)
2313                         vif = ipmr_find_vif(mrt, dev);
2314                 if (vif < 0) {
2315                         rcu_read_unlock();
2316                         return -ENODEV;
2317                 }
2318
2319                 skb2 = skb_realloc_headroom(skb, sizeof(struct iphdr));
2320                 if (!skb2) {
2321                         rcu_read_unlock();
2322                         return -ENOMEM;
2323                 }
2324
2325                 NETLINK_CB(skb2).portid = portid;
2326                 skb_push(skb2, sizeof(struct iphdr));
2327                 skb_reset_network_header(skb2);
2328                 iph = ip_hdr(skb2);
2329                 iph->ihl = sizeof(struct iphdr) >> 2;
2330                 iph->saddr = saddr;
2331                 iph->daddr = daddr;
2332                 iph->version = 0;
2333                 err = ipmr_cache_unresolved(mrt, vif, skb2, dev);
2334                 rcu_read_unlock();
2335                 return err;
2336         }
2337
2338         err = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
2339         rcu_read_unlock();
2340         return err;
2341 }
2342
2343 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2344                             u32 portid, u32 seq, struct mfc_cache *c, int cmd,
2345                             int flags)
2346 {
2347         struct nlmsghdr *nlh;
2348         struct rtmsg *rtm;
2349         int err;
2350
2351         nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2352         if (!nlh)
2353                 return -EMSGSIZE;
2354
2355         rtm = nlmsg_data(nlh);
2356         rtm->rtm_family   = RTNL_FAMILY_IPMR;
2357         rtm->rtm_dst_len  = 32;
2358         rtm->rtm_src_len  = 32;
2359         rtm->rtm_tos      = 0;
2360         rtm->rtm_table    = mrt->id;
2361         if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2362                 goto nla_put_failure;
2363         rtm->rtm_type     = RTN_MULTICAST;
2364         rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2365         if (c->_c.mfc_flags & MFC_STATIC)
2366                 rtm->rtm_protocol = RTPROT_STATIC;
2367         else
2368                 rtm->rtm_protocol = RTPROT_MROUTED;
2369         rtm->rtm_flags    = 0;
2370
2371         if (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) ||
2372             nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp))
2373                 goto nla_put_failure;
2374         err = mr_fill_mroute(mrt, skb, &c->_c, rtm);
2375         /* do not break the dump if cache is unresolved */
2376         if (err < 0 && err != -ENOENT)
2377                 goto nla_put_failure;
2378
2379         nlmsg_end(skb, nlh);
2380         return 0;
2381
2382 nla_put_failure:
2383         nlmsg_cancel(skb, nlh);
2384         return -EMSGSIZE;
2385 }
2386
2387 static int _ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2388                              u32 portid, u32 seq, struct mr_mfc *c, int cmd,
2389                              int flags)
2390 {
2391         return ipmr_fill_mroute(mrt, skb, portid, seq, (struct mfc_cache *)c,
2392                                 cmd, flags);
2393 }
2394
2395 static size_t mroute_msgsize(bool unresolved, int maxvif)
2396 {
2397         size_t len =
2398                 NLMSG_ALIGN(sizeof(struct rtmsg))
2399                 + nla_total_size(4)     /* RTA_TABLE */
2400                 + nla_total_size(4)     /* RTA_SRC */
2401                 + nla_total_size(4)     /* RTA_DST */
2402                 ;
2403
2404         if (!unresolved)
2405                 len = len
2406                       + nla_total_size(4)       /* RTA_IIF */
2407                       + nla_total_size(0)       /* RTA_MULTIPATH */
2408                       + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2409                                                 /* RTA_MFC_STATS */
2410                       + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
2411                 ;
2412
2413         return len;
2414 }
2415
2416 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2417                                  int cmd)
2418 {
2419         struct net *net = read_pnet(&mrt->net);
2420         struct sk_buff *skb;
2421         int err = -ENOBUFS;
2422
2423         skb = nlmsg_new(mroute_msgsize(mfc->_c.mfc_parent >= MAXVIFS,
2424                                        mrt->maxvif),
2425                         GFP_ATOMIC);
2426         if (!skb)
2427                 goto errout;
2428
2429         err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2430         if (err < 0)
2431                 goto errout;
2432
2433         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2434         return;
2435
2436 errout:
2437         kfree_skb(skb);
2438         rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
2439 }
2440
2441 static size_t igmpmsg_netlink_msgsize(size_t payloadlen)
2442 {
2443         size_t len =
2444                 NLMSG_ALIGN(sizeof(struct rtgenmsg))
2445                 + nla_total_size(1)     /* IPMRA_CREPORT_MSGTYPE */
2446                 + nla_total_size(4)     /* IPMRA_CREPORT_VIF_ID */
2447                 + nla_total_size(4)     /* IPMRA_CREPORT_SRC_ADDR */
2448                 + nla_total_size(4)     /* IPMRA_CREPORT_DST_ADDR */
2449                 + nla_total_size(4)     /* IPMRA_CREPORT_TABLE */
2450                                         /* IPMRA_CREPORT_PKT */
2451                 + nla_total_size(payloadlen)
2452                 ;
2453
2454         return len;
2455 }
2456
2457 static void igmpmsg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt)
2458 {
2459         struct net *net = read_pnet(&mrt->net);
2460         struct nlmsghdr *nlh;
2461         struct rtgenmsg *rtgenm;
2462         struct igmpmsg *msg;
2463         struct sk_buff *skb;
2464         struct nlattr *nla;
2465         int payloadlen;
2466
2467         payloadlen = pkt->len - sizeof(struct igmpmsg);
2468         msg = (struct igmpmsg *)skb_network_header(pkt);
2469
2470         skb = nlmsg_new(igmpmsg_netlink_msgsize(payloadlen), GFP_ATOMIC);
2471         if (!skb)
2472                 goto errout;
2473
2474         nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
2475                         sizeof(struct rtgenmsg), 0);
2476         if (!nlh)
2477                 goto errout;
2478         rtgenm = nlmsg_data(nlh);
2479         rtgenm->rtgen_family = RTNL_FAMILY_IPMR;
2480         if (nla_put_u8(skb, IPMRA_CREPORT_MSGTYPE, msg->im_msgtype) ||
2481             nla_put_u32(skb, IPMRA_CREPORT_VIF_ID, msg->im_vif | (msg->im_vif_hi << 8)) ||
2482             nla_put_in_addr(skb, IPMRA_CREPORT_SRC_ADDR,
2483                             msg->im_src.s_addr) ||
2484             nla_put_in_addr(skb, IPMRA_CREPORT_DST_ADDR,
2485                             msg->im_dst.s_addr) ||
2486             nla_put_u32(skb, IPMRA_CREPORT_TABLE, mrt->id))
2487                 goto nla_put_failure;
2488
2489         nla = nla_reserve(skb, IPMRA_CREPORT_PKT, payloadlen);
2490         if (!nla || skb_copy_bits(pkt, sizeof(struct igmpmsg),
2491                                   nla_data(nla), payloadlen))
2492                 goto nla_put_failure;
2493
2494         nlmsg_end(skb, nlh);
2495
2496         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE_R, NULL, GFP_ATOMIC);
2497         return;
2498
2499 nla_put_failure:
2500         nlmsg_cancel(skb, nlh);
2501 errout:
2502         kfree_skb(skb);
2503         rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE_R, -ENOBUFS);
2504 }
2505
2506 static int ipmr_rtm_valid_getroute_req(struct sk_buff *skb,
2507                                        const struct nlmsghdr *nlh,
2508                                        struct nlattr **tb,
2509                                        struct netlink_ext_ack *extack)
2510 {
2511         struct rtmsg *rtm;
2512         int i, err;
2513
2514         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2515                 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for multicast route get request");
2516                 return -EINVAL;
2517         }
2518
2519         if (!netlink_strict_get_check(skb))
2520                 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
2521                                               rtm_ipv4_policy, extack);
2522
2523         rtm = nlmsg_data(nlh);
2524         if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) ||
2525             (rtm->rtm_dst_len && rtm->rtm_dst_len != 32) ||
2526             rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol ||
2527             rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) {
2528                 NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for multicast route get request");
2529                 return -EINVAL;
2530         }
2531
2532         err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2533                                             rtm_ipv4_policy, extack);
2534         if (err)
2535                 return err;
2536
2537         if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
2538             (tb[RTA_DST] && !rtm->rtm_dst_len)) {
2539                 NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4");
2540                 return -EINVAL;
2541         }
2542
2543         for (i = 0; i <= RTA_MAX; i++) {
2544                 if (!tb[i])
2545                         continue;
2546
2547                 switch (i) {
2548                 case RTA_SRC:
2549                 case RTA_DST:
2550                 case RTA_TABLE:
2551                         break;
2552                 default:
2553                         NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in multicast route get request");
2554                         return -EINVAL;
2555                 }
2556         }
2557
2558         return 0;
2559 }
2560
2561 static int ipmr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2562                              struct netlink_ext_ack *extack)
2563 {
2564         struct net *net = sock_net(in_skb->sk);
2565         struct nlattr *tb[RTA_MAX + 1];
2566         struct sk_buff *skb = NULL;
2567         struct mfc_cache *cache;
2568         struct mr_table *mrt;
2569         __be32 src, grp;
2570         u32 tableid;
2571         int err;
2572
2573         err = ipmr_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
2574         if (err < 0)
2575                 goto errout;
2576
2577         src = nla_get_in_addr_default(tb[RTA_SRC], 0);
2578         grp = nla_get_in_addr_default(tb[RTA_DST], 0);
2579         tableid = nla_get_u32_default(tb[RTA_TABLE], 0);
2580
2581         mrt = __ipmr_get_table(net, tableid ? tableid : RT_TABLE_DEFAULT);
2582         if (!mrt) {
2583                 err = -ENOENT;
2584                 goto errout_free;
2585         }
2586
2587         /* entries are added/deleted only under RTNL */
2588         rcu_read_lock();
2589         cache = ipmr_cache_find(mrt, src, grp);
2590         rcu_read_unlock();
2591         if (!cache) {
2592                 err = -ENOENT;
2593                 goto errout_free;
2594         }
2595
2596         skb = nlmsg_new(mroute_msgsize(false, mrt->maxvif), GFP_KERNEL);
2597         if (!skb) {
2598                 err = -ENOBUFS;
2599                 goto errout_free;
2600         }
2601
2602         err = ipmr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
2603                                nlh->nlmsg_seq, cache,
2604                                RTM_NEWROUTE, 0);
2605         if (err < 0)
2606                 goto errout_free;
2607
2608         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2609
2610 errout:
2611         return err;
2612
2613 errout_free:
2614         kfree_skb(skb);
2615         goto errout;
2616 }
2617
2618 static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2619 {
2620         struct fib_dump_filter filter = {
2621                 .rtnl_held = true,
2622         };
2623         int err;
2624
2625         if (cb->strict_check) {
2626                 err = ip_valid_fib_dump_req(sock_net(skb->sk), cb->nlh,
2627                                             &filter, cb);
2628                 if (err < 0)
2629                         return err;
2630         }
2631
2632         if (filter.table_id) {
2633                 struct mr_table *mrt;
2634
2635                 mrt = __ipmr_get_table(sock_net(skb->sk), filter.table_id);
2636                 if (!mrt) {
2637                         if (rtnl_msg_family(cb->nlh) != RTNL_FAMILY_IPMR)
2638                                 return skb->len;
2639
2640                         NL_SET_ERR_MSG(cb->extack, "ipv4: MR table does not exist");
2641                         return -ENOENT;
2642                 }
2643                 err = mr_table_dump(mrt, skb, cb, _ipmr_fill_mroute,
2644                                     &mfc_unres_lock, &filter);
2645                 return skb->len ? : err;
2646         }
2647
2648         return mr_rtm_dumproute(skb, cb, ipmr_mr_table_iter,
2649                                 _ipmr_fill_mroute, &mfc_unres_lock, &filter);
2650 }
2651
2652 static const struct nla_policy rtm_ipmr_policy[RTA_MAX + 1] = {
2653         [RTA_SRC]       = { .type = NLA_U32 },
2654         [RTA_DST]       = { .type = NLA_U32 },
2655         [RTA_IIF]       = { .type = NLA_U32 },
2656         [RTA_TABLE]     = { .type = NLA_U32 },
2657         [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
2658 };
2659
2660 static bool ipmr_rtm_validate_proto(unsigned char rtm_protocol)
2661 {
2662         switch (rtm_protocol) {
2663         case RTPROT_STATIC:
2664         case RTPROT_MROUTED:
2665                 return true;
2666         }
2667         return false;
2668 }
2669
2670 static int ipmr_nla_get_ttls(const struct nlattr *nla, struct mfcctl *mfcc)
2671 {
2672         struct rtnexthop *rtnh = nla_data(nla);
2673         int remaining = nla_len(nla), vifi = 0;
2674
2675         while (rtnh_ok(rtnh, remaining)) {
2676                 mfcc->mfcc_ttls[vifi] = rtnh->rtnh_hops;
2677                 if (++vifi == MAXVIFS)
2678                         break;
2679                 rtnh = rtnh_next(rtnh, &remaining);
2680         }
2681
2682         return remaining > 0 ? -EINVAL : vifi;
2683 }
2684
2685 /* returns < 0 on error, 0 for ADD_MFC and 1 for ADD_MFC_PROXY */
2686 static int rtm_to_ipmr_mfcc(struct net *net, struct nlmsghdr *nlh,
2687                             struct mfcctl *mfcc, int *mrtsock,
2688                             struct mr_table **mrtret,
2689                             struct netlink_ext_ack *extack)
2690 {
2691         struct net_device *dev = NULL;
2692         u32 tblid = RT_TABLE_DEFAULT;
2693         struct mr_table *mrt;
2694         struct nlattr *attr;
2695         struct rtmsg *rtm;
2696         int ret, rem;
2697
2698         ret = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX,
2699                                         rtm_ipmr_policy, extack);
2700         if (ret < 0)
2701                 goto out;
2702         rtm = nlmsg_data(nlh);
2703
2704         ret = -EINVAL;
2705         if (rtm->rtm_family != RTNL_FAMILY_IPMR || rtm->rtm_dst_len != 32 ||
2706             rtm->rtm_type != RTN_MULTICAST ||
2707             rtm->rtm_scope != RT_SCOPE_UNIVERSE ||
2708             !ipmr_rtm_validate_proto(rtm->rtm_protocol))
2709                 goto out;
2710
2711         memset(mfcc, 0, sizeof(*mfcc));
2712         mfcc->mfcc_parent = -1;
2713         ret = 0;
2714         nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), rem) {
2715                 switch (nla_type(attr)) {
2716                 case RTA_SRC:
2717                         mfcc->mfcc_origin.s_addr = nla_get_be32(attr);
2718                         break;
2719                 case RTA_DST:
2720                         mfcc->mfcc_mcastgrp.s_addr = nla_get_be32(attr);
2721                         break;
2722                 case RTA_IIF:
2723                         dev = __dev_get_by_index(net, nla_get_u32(attr));
2724                         if (!dev) {
2725                                 ret = -ENODEV;
2726                                 goto out;
2727                         }
2728                         break;
2729                 case RTA_MULTIPATH:
2730                         if (ipmr_nla_get_ttls(attr, mfcc) < 0) {
2731                                 ret = -EINVAL;
2732                                 goto out;
2733                         }
2734                         break;
2735                 case RTA_PREFSRC:
2736                         ret = 1;
2737                         break;
2738                 case RTA_TABLE:
2739                         tblid = nla_get_u32(attr);
2740                         break;
2741                 }
2742         }
2743         mrt = __ipmr_get_table(net, tblid);
2744         if (!mrt) {
2745                 ret = -ENOENT;
2746                 goto out;
2747         }
2748         *mrtret = mrt;
2749         *mrtsock = rtm->rtm_protocol == RTPROT_MROUTED ? 1 : 0;
2750         if (dev)
2751                 mfcc->mfcc_parent = ipmr_find_vif(mrt, dev);
2752
2753 out:
2754         return ret;
2755 }
2756
2757 /* takes care of both newroute and delroute */
2758 static int ipmr_rtm_route(struct sk_buff *skb, struct nlmsghdr *nlh,
2759                           struct netlink_ext_ack *extack)
2760 {
2761         struct net *net = sock_net(skb->sk);
2762         int ret, mrtsock, parent;
2763         struct mr_table *tbl;
2764         struct mfcctl mfcc;
2765
2766         mrtsock = 0;
2767         tbl = NULL;
2768         ret = rtm_to_ipmr_mfcc(net, nlh, &mfcc, &mrtsock, &tbl, extack);
2769         if (ret < 0)
2770                 return ret;
2771
2772         parent = ret ? mfcc.mfcc_parent : -1;
2773         if (nlh->nlmsg_type == RTM_NEWROUTE)
2774                 return ipmr_mfc_add(net, tbl, &mfcc, mrtsock, parent);
2775         else
2776                 return ipmr_mfc_delete(tbl, &mfcc, parent);
2777 }
2778
2779 static bool ipmr_fill_table(struct mr_table *mrt, struct sk_buff *skb)
2780 {
2781         u32 queue_len = atomic_read(&mrt->cache_resolve_queue_len);
2782
2783         if (nla_put_u32(skb, IPMRA_TABLE_ID, mrt->id) ||
2784             nla_put_u32(skb, IPMRA_TABLE_CACHE_RES_QUEUE_LEN, queue_len) ||
2785             nla_put_s32(skb, IPMRA_TABLE_MROUTE_REG_VIF_NUM,
2786                         mrt->mroute_reg_vif_num) ||
2787             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_ASSERT,
2788                        mrt->mroute_do_assert) ||
2789             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_PIM, mrt->mroute_do_pim) ||
2790             nla_put_u8(skb, IPMRA_TABLE_MROUTE_DO_WRVIFWHOLE,
2791                        mrt->mroute_do_wrvifwhole))
2792                 return false;
2793
2794         return true;
2795 }
2796
2797 static bool ipmr_fill_vif(struct mr_table *mrt, u32 vifid, struct sk_buff *skb)
2798 {
2799         struct net_device *vif_dev;
2800         struct nlattr *vif_nest;
2801         struct vif_device *vif;
2802
2803         vif = &mrt->vif_table[vifid];
2804         vif_dev = rtnl_dereference(vif->dev);
2805         /* if the VIF doesn't exist just continue */
2806         if (!vif_dev)
2807                 return true;
2808
2809         vif_nest = nla_nest_start_noflag(skb, IPMRA_VIF);
2810         if (!vif_nest)
2811                 return false;
2812
2813         if (nla_put_u32(skb, IPMRA_VIFA_IFINDEX, vif_dev->ifindex) ||
2814             nla_put_u32(skb, IPMRA_VIFA_VIF_ID, vifid) ||
2815             nla_put_u16(skb, IPMRA_VIFA_FLAGS, vif->flags) ||
2816             nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_IN, vif->bytes_in,
2817                               IPMRA_VIFA_PAD) ||
2818             nla_put_u64_64bit(skb, IPMRA_VIFA_BYTES_OUT, vif->bytes_out,
2819                               IPMRA_VIFA_PAD) ||
2820             nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_IN, vif->pkt_in,
2821                               IPMRA_VIFA_PAD) ||
2822             nla_put_u64_64bit(skb, IPMRA_VIFA_PACKETS_OUT, vif->pkt_out,
2823                               IPMRA_VIFA_PAD) ||
2824             nla_put_be32(skb, IPMRA_VIFA_LOCAL_ADDR, vif->local) ||
2825             nla_put_be32(skb, IPMRA_VIFA_REMOTE_ADDR, vif->remote)) {
2826                 nla_nest_cancel(skb, vif_nest);
2827                 return false;
2828         }
2829         nla_nest_end(skb, vif_nest);
2830
2831         return true;
2832 }
2833
2834 static int ipmr_valid_dumplink(const struct nlmsghdr *nlh,
2835                                struct netlink_ext_ack *extack)
2836 {
2837         struct ifinfomsg *ifm;
2838
2839         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
2840                 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for ipmr link dump");
2841                 return -EINVAL;
2842         }
2843
2844         if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
2845                 NL_SET_ERR_MSG(extack, "Invalid data after header in ipmr link dump");
2846                 return -EINVAL;
2847         }
2848
2849         ifm = nlmsg_data(nlh);
2850         if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
2851             ifm->ifi_change || ifm->ifi_index) {
2852                 NL_SET_ERR_MSG(extack, "Invalid values in header for ipmr link dump request");
2853                 return -EINVAL;
2854         }
2855
2856         return 0;
2857 }
2858
2859 static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback *cb)
2860 {
2861         struct net *net = sock_net(skb->sk);
2862         struct nlmsghdr *nlh = NULL;
2863         unsigned int t = 0, s_t;
2864         unsigned int e = 0, s_e;
2865         struct mr_table *mrt;
2866
2867         if (cb->strict_check) {
2868                 int err = ipmr_valid_dumplink(cb->nlh, cb->extack);
2869
2870                 if (err < 0)
2871                         return err;
2872         }
2873
2874         s_t = cb->args[0];
2875         s_e = cb->args[1];
2876
2877         ipmr_for_each_table(mrt, net) {
2878                 struct nlattr *vifs, *af;
2879                 struct ifinfomsg *hdr;
2880                 u32 i;
2881
2882                 if (t < s_t)
2883                         goto skip_table;
2884                 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
2885                                 cb->nlh->nlmsg_seq, RTM_NEWLINK,
2886                                 sizeof(*hdr), NLM_F_MULTI);
2887                 if (!nlh)
2888                         break;
2889
2890                 hdr = nlmsg_data(nlh);
2891                 memset(hdr, 0, sizeof(*hdr));
2892                 hdr->ifi_family = RTNL_FAMILY_IPMR;
2893
2894                 af = nla_nest_start_noflag(skb, IFLA_AF_SPEC);
2895                 if (!af) {
2896                         nlmsg_cancel(skb, nlh);
2897                         goto out;
2898                 }
2899
2900                 if (!ipmr_fill_table(mrt, skb)) {
2901                         nlmsg_cancel(skb, nlh);
2902                         goto out;
2903                 }
2904
2905                 vifs = nla_nest_start_noflag(skb, IPMRA_TABLE_VIFS);
2906                 if (!vifs) {
2907                         nla_nest_end(skb, af);
2908                         nlmsg_end(skb, nlh);
2909                         goto out;
2910                 }
2911                 for (i = 0; i < mrt->maxvif; i++) {
2912                         if (e < s_e)
2913                                 goto skip_entry;
2914                         if (!ipmr_fill_vif(mrt, i, skb)) {
2915                                 nla_nest_end(skb, vifs);
2916                                 nla_nest_end(skb, af);
2917                                 nlmsg_end(skb, nlh);
2918                                 goto out;
2919                         }
2920 skip_entry:
2921                         e++;
2922                 }
2923                 s_e = 0;
2924                 e = 0;
2925                 nla_nest_end(skb, vifs);
2926                 nla_nest_end(skb, af);
2927                 nlmsg_end(skb, nlh);
2928 skip_table:
2929                 t++;
2930         }
2931
2932 out:
2933         cb->args[1] = e;
2934         cb->args[0] = t;
2935
2936         return skb->len;
2937 }
2938
2939 #ifdef CONFIG_PROC_FS
2940 /* The /proc interfaces to multicast routing :
2941  * /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2942  */
2943
2944 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2945         __acquires(RCU)
2946 {
2947         struct mr_vif_iter *iter = seq->private;
2948         struct net *net = seq_file_net(seq);
2949         struct mr_table *mrt;
2950
2951         rcu_read_lock();
2952         mrt = __ipmr_get_table(net, RT_TABLE_DEFAULT);
2953         if (!mrt) {
2954                 rcu_read_unlock();
2955                 return ERR_PTR(-ENOENT);
2956         }
2957
2958         iter->mrt = mrt;
2959
2960         return mr_vif_seq_start(seq, pos);
2961 }
2962
2963 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2964         __releases(RCU)
2965 {
2966         rcu_read_unlock();
2967 }
2968
2969 static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2970 {
2971         struct mr_vif_iter *iter = seq->private;
2972         struct mr_table *mrt = iter->mrt;
2973
2974         if (v == SEQ_START_TOKEN) {
2975                 seq_puts(seq,
2976                          "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
2977         } else {
2978                 const struct vif_device *vif = v;
2979                 const struct net_device *vif_dev;
2980                 const char *name;
2981
2982                 vif_dev = vif_dev_read(vif);
2983                 name = vif_dev ? vif_dev->name : "none";
2984                 seq_printf(seq,
2985                            "%2td %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
2986                            vif - mrt->vif_table,
2987                            name, vif->bytes_in, vif->pkt_in,
2988                            vif->bytes_out, vif->pkt_out,
2989                            vif->flags, vif->local, vif->remote);
2990         }
2991         return 0;
2992 }
2993
2994 static const struct seq_operations ipmr_vif_seq_ops = {
2995         .start = ipmr_vif_seq_start,
2996         .next  = mr_vif_seq_next,
2997         .stop  = ipmr_vif_seq_stop,
2998         .show  = ipmr_vif_seq_show,
2999 };
3000
3001 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
3002 {
3003         struct net *net = seq_file_net(seq);
3004         struct mr_table *mrt;
3005
3006         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
3007         if (!mrt)
3008                 return ERR_PTR(-ENOENT);
3009
3010         return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
3011 }
3012
3013 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
3014 {
3015         int n;
3016
3017         if (v == SEQ_START_TOKEN) {
3018                 seq_puts(seq,
3019                  "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
3020         } else {
3021                 const struct mfc_cache *mfc = v;
3022                 const struct mr_mfc_iter *it = seq->private;
3023                 const struct mr_table *mrt = it->mrt;
3024
3025                 seq_printf(seq, "%08X %08X %-3hd",
3026                            (__force u32) mfc->mfc_mcastgrp,
3027                            (__force u32) mfc->mfc_origin,
3028                            mfc->_c.mfc_parent);
3029
3030                 if (it->cache != &mrt->mfc_unres_queue) {
3031                         seq_printf(seq, " %8lu %8lu %8lu",
3032                                    mfc->_c.mfc_un.res.pkt,
3033                                    mfc->_c.mfc_un.res.bytes,
3034                                    mfc->_c.mfc_un.res.wrong_if);
3035                         for (n = mfc->_c.mfc_un.res.minvif;
3036                              n < mfc->_c.mfc_un.res.maxvif; n++) {
3037                                 if (VIF_EXISTS(mrt, n) &&
3038                                     mfc->_c.mfc_un.res.ttls[n] < 255)
3039                                         seq_printf(seq,
3040                                            " %2d:%-3d",
3041                                            n, mfc->_c.mfc_un.res.ttls[n]);
3042                         }
3043                 } else {
3044                         /* unresolved mfc_caches don't contain
3045                          * pkt, bytes and wrong_if values
3046                          */
3047                         seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
3048                 }
3049                 seq_putc(seq, '\n');
3050         }
3051         return 0;
3052 }
3053
3054 static const struct seq_operations ipmr_mfc_seq_ops = {
3055         .start = ipmr_mfc_seq_start,
3056         .next  = mr_mfc_seq_next,
3057         .stop  = mr_mfc_seq_stop,
3058         .show  = ipmr_mfc_seq_show,
3059 };
3060 #endif
3061
3062 #ifdef CONFIG_IP_PIMSM_V2
3063 static const struct net_protocol pim_protocol = {
3064         .handler        =       pim_rcv,
3065 };
3066 #endif
3067
3068 static unsigned int ipmr_seq_read(const struct net *net)
3069 {
3070         return READ_ONCE(net->ipv4.ipmr_seq) + ipmr_rules_seq_read(net);
3071 }
3072
3073 static int ipmr_dump(struct net *net, struct notifier_block *nb,
3074                      struct netlink_ext_ack *extack)
3075 {
3076         return mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump,
3077                        ipmr_mr_table_iter, extack);
3078 }
3079
3080 static const struct fib_notifier_ops ipmr_notifier_ops_template = {
3081         .family         = RTNL_FAMILY_IPMR,
3082         .fib_seq_read   = ipmr_seq_read,
3083         .fib_dump       = ipmr_dump,
3084         .owner          = THIS_MODULE,
3085 };
3086
3087 static int __net_init ipmr_notifier_init(struct net *net)
3088 {
3089         struct fib_notifier_ops *ops;
3090
3091         net->ipv4.ipmr_seq = 0;
3092
3093         ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net);
3094         if (IS_ERR(ops))
3095                 return PTR_ERR(ops);
3096         net->ipv4.ipmr_notifier_ops = ops;
3097
3098         return 0;
3099 }
3100
3101 static void __net_exit ipmr_notifier_exit(struct net *net)
3102 {
3103         fib_notifier_ops_unregister(net->ipv4.ipmr_notifier_ops);
3104         net->ipv4.ipmr_notifier_ops = NULL;
3105 }
3106
3107 /* Setup for IP multicast routing */
3108 static int __net_init ipmr_net_init(struct net *net)
3109 {
3110         int err;
3111
3112         err = ipmr_notifier_init(net);
3113         if (err)
3114                 goto ipmr_notifier_fail;
3115
3116         err = ipmr_rules_init(net);
3117         if (err < 0)
3118                 goto ipmr_rules_fail;
3119
3120 #ifdef CONFIG_PROC_FS
3121         err = -ENOMEM;
3122         if (!proc_create_net("ip_mr_vif", 0, net->proc_net, &ipmr_vif_seq_ops,
3123                         sizeof(struct mr_vif_iter)))
3124                 goto proc_vif_fail;
3125         if (!proc_create_net("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
3126                         sizeof(struct mr_mfc_iter)))
3127                 goto proc_cache_fail;
3128 #endif
3129         return 0;
3130
3131 #ifdef CONFIG_PROC_FS
3132 proc_cache_fail:
3133         remove_proc_entry("ip_mr_vif", net->proc_net);
3134 proc_vif_fail:
3135         rtnl_lock();
3136         ipmr_rules_exit(net);
3137         rtnl_unlock();
3138 #endif
3139 ipmr_rules_fail:
3140         ipmr_notifier_exit(net);
3141 ipmr_notifier_fail:
3142         return err;
3143 }
3144
3145 static void __net_exit ipmr_net_exit(struct net *net)
3146 {
3147 #ifdef CONFIG_PROC_FS
3148         remove_proc_entry("ip_mr_cache", net->proc_net);
3149         remove_proc_entry("ip_mr_vif", net->proc_net);
3150 #endif
3151         ipmr_notifier_exit(net);
3152 }
3153
3154 static void __net_exit ipmr_net_exit_batch(struct list_head *net_list)
3155 {
3156         struct net *net;
3157
3158         rtnl_lock();
3159         list_for_each_entry(net, net_list, exit_list)
3160                 ipmr_rules_exit(net);
3161         rtnl_unlock();
3162 }
3163
3164 static struct pernet_operations ipmr_net_ops = {
3165         .init = ipmr_net_init,
3166         .exit = ipmr_net_exit,
3167         .exit_batch = ipmr_net_exit_batch,
3168 };
3169
3170 static const struct rtnl_msg_handler ipmr_rtnl_msg_handlers[] __initconst = {
3171         {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_GETLINK,
3172          .dumpit = ipmr_rtm_dumplink},
3173         {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_NEWROUTE,
3174          .doit = ipmr_rtm_route},
3175         {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_DELROUTE,
3176          .doit = ipmr_rtm_route},
3177         {.protocol = RTNL_FAMILY_IPMR, .msgtype = RTM_GETROUTE,
3178          .doit = ipmr_rtm_getroute, .dumpit = ipmr_rtm_dumproute},
3179 };
3180
3181 int __init ip_mr_init(void)
3182 {
3183         int err;
3184
3185         mrt_cachep = KMEM_CACHE(mfc_cache, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
3186
3187         err = register_pernet_subsys(&ipmr_net_ops);
3188         if (err)
3189                 goto reg_pernet_fail;
3190
3191         err = register_netdevice_notifier(&ip_mr_notifier);
3192         if (err)
3193                 goto reg_notif_fail;
3194 #ifdef CONFIG_IP_PIMSM_V2
3195         if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
3196                 pr_err("%s: can't add PIM protocol\n", __func__);
3197                 err = -EAGAIN;
3198                 goto add_proto_fail;
3199         }
3200 #endif
3201         rtnl_register_many(ipmr_rtnl_msg_handlers);
3202
3203         return 0;
3204
3205 #ifdef CONFIG_IP_PIMSM_V2
3206 add_proto_fail:
3207         unregister_netdevice_notifier(&ip_mr_notifier);
3208 #endif
3209 reg_notif_fail:
3210         unregister_pernet_subsys(&ipmr_net_ops);
3211 reg_pernet_fail:
3212         kmem_cache_destroy(mrt_cachep);
3213         return err;
3214 }