net/ipv4/ipmr.c

   1 /*
   2  *      IP multicast routing support for mrouted 3.6/3.8
   3  *
   4  *              (c) 1995 Alan Cox, <[email protected]>
   5  *        Linux Consultancy and Custom Driver Development
   6  *
   7  *      This program is free software; you can redistribute it and/or
   8  *      modify it under the terms of the GNU General Public License
   9  *      as published by the Free Software Foundation; either version
  10  *      2 of the License, or (at your option) any later version.
  11  *
  12  *      Fixes:
  13  *      Michael Chastain        :       Incorrect size of copying.
  14  *      Alan Cox                :       Added the cache manager code
  15  *      Alan Cox                :       Fixed the clone/copy bug and device race.
  16  *      Mike McLagan            :       Routing by source
  17  *      Malcolm Beattie         :       Buffer handling fixes.
  18  *      Alexey Kuznetsov        :       Double buffer free and other fixes.
  19  *      SVR Anand               :       Fixed several multicast bugs and problems.
  20  *      Alexey Kuznetsov        :       Status, optimisations and more.
  21  *      Brad Parker             :       Better behaviour on mrouted upcall
  22  *                                      overflow.
  23  *      Carlos Picoto           :       PIMv1 Support
  24  *      Pavlin Ivanov Radoslavov:       PIMv2 Registers must checksum only PIM header
  25  *                                      Relax this requirement to work with older peers.
  26  *
  27  */
  28
  29 #include <asm/uaccess.h>
  30 #include <linux/types.h>
  31 #include <linux/capability.h>
  32 #include <linux/errno.h>
  33 #include <linux/timer.h>
  34 #include <linux/mm.h>
  35 #include <linux/kernel.h>
  36 #include <linux/fcntl.h>
  37 #include <linux/stat.h>
  38 #include <linux/socket.h>
  39 #include <linux/in.h>
  40 #include <linux/inet.h>
  41 #include <linux/netdevice.h>
  42 #include <linux/inetdevice.h>
  43 #include <linux/igmp.h>
  44 #include <linux/proc_fs.h>
  45 #include <linux/seq_file.h>
  46 #include <linux/mroute.h>
  47 #include <linux/init.h>
  48 #include <linux/if_ether.h>
  49 #include <linux/slab.h>
  50 #include <net/net_namespace.h>
  51 #include <net/ip.h>
  52 #include <net/protocol.h>
  53 #include <linux/skbuff.h>
  54 #include <net/route.h>
  55 #include <net/sock.h>
  56 #include <net/icmp.h>
  57 #include <net/udp.h>
  58 #include <net/raw.h>
  59 #include <linux/notifier.h>
  60 #include <linux/if_arp.h>
  61 #include <linux/netfilter_ipv4.h>
  62 #include <linux/compat.h>
  63 #include <linux/export.h>
  64 #include <net/ip_tunnels.h>
  65 #include <net/checksum.h>
  66 #include <net/netlink.h>
  67 #include <net/fib_rules.h>
  68 #include <linux/netconf.h>
  69
  70 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
  71 #define CONFIG_IP_PIMSM 1
  72 #endif
  73
  74 struct mr_table {
  75         struct list_head        list;
  76 #ifdef CONFIG_NET_NS
  77         struct net              *net;
  78 #endif
  79         u32                     id;
  80         struct sock __rcu       *mroute_sk;
  81         struct timer_list       ipmr_expire_timer;
  82         struct list_head        mfc_unres_queue;
  83         struct list_head        mfc_cache_array[MFC_LINES];
  84         struct vif_device       vif_table[MAXVIFS];
  85         int                     maxvif;
  86         atomic_t                cache_resolve_queue_len;
  87         bool                    mroute_do_assert;
  88         bool                    mroute_do_pim;
  89 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
  90         int                     mroute_reg_vif_num;
  91 #endif
  92 };
  93
  94 struct ipmr_rule {
  95         struct fib_rule         common;
  96 };
  97
  98 struct ipmr_result {
  99         struct mr_table         *mrt;
 100 };
 101
 102 /* Big lock, protecting vif table, mrt cache and mroute socket state.
 103  * Note that the changes are semaphored via rtnl_lock.
 104  */
 105
 106 static DEFINE_RWLOCK(mrt_lock);
 107
 108 /*
 109  *      Multicast router control variables
 110  */
 111
 112 #define VIF_EXISTS(_mrt, _idx) ((_mrt)->vif_table[_idx].dev != NULL)
 113
 114 /* Special spinlock for queue of unresolved entries */
 115 static DEFINE_SPINLOCK(mfc_unres_lock);
 116
 117 /* We return to original Alan's scheme. Hash table of resolved
 118  * entries is changed only in process context and protected
 119  * with weak lock mrt_lock. Queue of unresolved entries is protected
 120  * with strong spinlock mfc_unres_lock.
 121  *
 122  * In this case data path is free of exclusive locks at all.
 123  */
 124
 125 static struct kmem_cache *mrt_cachep __read_mostly;
 126
 127 static struct mr_table *ipmr_new_table(struct net *net, u32 id);
 128 static void ipmr_free_table(struct mr_table *mrt);
 129
 130 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
 131                           struct sk_buff *skb, struct mfc_cache *cache,
 132                           int local);
 133 static int ipmr_cache_report(struct mr_table *mrt,
 134                              struct sk_buff *pkt, vifi_t vifi, int assert);
 135 static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
 136                               struct mfc_cache *c, struct rtmsg *rtm);
 137 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
 138                                  int cmd);
 139 static void mroute_clean_tables(struct mr_table *mrt);
 140 static void ipmr_expire_process(unsigned long arg);
 141
 142 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 143 #define ipmr_for_each_table(mrt, net) \
 144         list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list)
 145
 146 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 147 {
 148         struct mr_table *mrt;
 149
 150         ipmr_for_each_table(mrt, net) {
 151                 if (mrt->id == id)
 152                         return mrt;
 153         }
 154         return NULL;
 155 }
 156
 157 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 158                            struct mr_table **mrt)
 159 {
 160         int err;
 161         struct ipmr_result res;
 162         struct fib_lookup_arg arg = {
 163                 .result = &res,
 164                 .flags = FIB_LOOKUP_NOREF,
 165         };
 166
 167         err = fib_rules_lookup(net->ipv4.mr_rules_ops,
 168                                flowi4_to_flowi(flp4), 0, &arg);
 169         if (err < 0)
 170                 return err;
 171         *mrt = res.mrt;
 172         return 0;
 173 }
 174
 175 static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
 176                             int flags, struct fib_lookup_arg *arg)
 177 {
 178         struct ipmr_result *res = arg->result;
 179         struct mr_table *mrt;
 180
 181         switch (rule->action) {
 182         case FR_ACT_TO_TBL:
 183                 break;
 184         case FR_ACT_UNREACHABLE:
 185                 return -ENETUNREACH;
 186         case FR_ACT_PROHIBIT:
 187                 return -EACCES;
 188         case FR_ACT_BLACKHOLE:
 189         default:
 190                 return -EINVAL;
 191         }
 192
 193         mrt = ipmr_get_table(rule->fr_net, rule->table);
 194         if (mrt == NULL)
 195                 return -EAGAIN;
 196         res->mrt = mrt;
 197         return 0;
 198 }
 199
 200 static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
 201 {
 202         return 1;
 203 }
 204
 205 static const struct nla_policy ipmr_rule_policy[FRA_MAX + 1] = {
 206         FRA_GENERIC_POLICY,
 207 };
 208
 209 static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
 210                                struct fib_rule_hdr *frh, struct nlattr **tb)
 211 {
 212         return 0;
 213 }
 214
 215 static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
 216                              struct nlattr **tb)
 217 {
 218         return 1;
 219 }
 220
 221 static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
 222                           struct fib_rule_hdr *frh)
 223 {
 224         frh->dst_len = 0;
 225         frh->src_len = 0;
 226         frh->tos     = 0;
 227         return 0;
 228 }
 229
 230 static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
 231         .family         = RTNL_FAMILY_IPMR,
 232         .rule_size      = sizeof(struct ipmr_rule),
 233         .addr_size      = sizeof(u32),
 234         .action         = ipmr_rule_action,
 235         .match          = ipmr_rule_match,
 236         .configure      = ipmr_rule_configure,
 237         .compare        = ipmr_rule_compare,
 238         .default_pref   = fib_default_rule_pref,
 239         .fill           = ipmr_rule_fill,
 240         .nlgroup        = RTNLGRP_IPV4_RULE,
 241         .policy         = ipmr_rule_policy,
 242         .owner          = THIS_MODULE,
 243 };
 244
 245 static int __net_init ipmr_rules_init(struct net *net)
 246 {
 247         struct fib_rules_ops *ops;
 248         struct mr_table *mrt;
 249         int err;
 250
 251         ops = fib_rules_register(&ipmr_rules_ops_template, net);
 252         if (IS_ERR(ops))
 253                 return PTR_ERR(ops);
 254
 255         INIT_LIST_HEAD(&net->ipv4.mr_tables);
 256
 257         mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 258         if (mrt == NULL) {
 259                 err = -ENOMEM;
 260                 goto err1;
 261         }
 262
 263         err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
 264         if (err < 0)
 265                 goto err2;
 266
 267         net->ipv4.mr_rules_ops = ops;
 268         return 0;
 269
 270 err2:
 271         kfree(mrt);
 272 err1:
 273         fib_rules_unregister(ops);
 274         return err;
 275 }
 276
 277 static void __net_exit ipmr_rules_exit(struct net *net)
 278 {
 279         struct mr_table *mrt, *next;
 280
 281         list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
 282                 list_del(&mrt->list);
 283                 ipmr_free_table(mrt);
 284         }
 285         fib_rules_unregister(net->ipv4.mr_rules_ops);
 286 }
 287 #else
 288 #define ipmr_for_each_table(mrt, net) \
 289         for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
 290
 291 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 292 {
 293         return net->ipv4.mrt;
 294 }
 295
 296 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 297                            struct mr_table **mrt)
 298 {
 299         *mrt = net->ipv4.mrt;
 300         return 0;
 301 }
 302
 303 static int __net_init ipmr_rules_init(struct net *net)
 304 {
 305         net->ipv4.mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 306         return net->ipv4.mrt ? 0 : -ENOMEM;
 307 }
 308
 309 static void __net_exit ipmr_rules_exit(struct net *net)
 310 {
 311         ipmr_free_table(net->ipv4.mrt);
 312 }
 313 #endif
 314
 315 static struct mr_table *ipmr_new_table(struct net *net, u32 id)
 316 {
 317         struct mr_table *mrt;
 318         unsigned int i;
 319
 320         mrt = ipmr_get_table(net, id);
 321         if (mrt != NULL)
 322                 return mrt;
 323
 324         mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
 325         if (mrt == NULL)
 326                 return NULL;
 327         write_pnet(&mrt->net, net);
 328         mrt->id = id;
 329
 330         /* Forwarding cache */
 331         for (i = 0; i < MFC_LINES; i++)
 332                 INIT_LIST_HEAD(&mrt->mfc_cache_array[i]);
 333
 334         INIT_LIST_HEAD(&mrt->mfc_unres_queue);
 335
 336         setup_timer(&mrt->ipmr_expire_timer, ipmr_expire_process,
 337                     (unsigned long)mrt);
 338
 339 #ifdef CONFIG_IP_PIMSM
 340         mrt->mroute_reg_vif_num = -1;
 341 #endif
 342 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 343         list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
 344 #endif
 345         return mrt;
 346 }
 347
 348 static void ipmr_free_table(struct mr_table *mrt)
 349 {
 350         del_timer_sync(&mrt->ipmr_expire_timer);
 351         mroute_clean_tables(mrt);
 352         kfree(mrt);
 353 }
 354
 355 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
 356
 357 static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
 358 {
 359         struct net *net = dev_net(dev);
 360
 361         dev_close(dev);
 362
 363         dev = __dev_get_by_name(net, "tunl0");
 364         if (dev) {
 365                 const struct net_device_ops *ops = dev->netdev_ops;
 366                 struct ifreq ifr;
 367                 struct ip_tunnel_parm p;
 368
 369                 memset(&p, 0, sizeof(p));
 370                 p.iph.daddr = v->vifc_rmt_addr.s_addr;
 371                 p.iph.saddr = v->vifc_lcl_addr.s_addr;
 372                 p.iph.version = 4;
 373                 p.iph.ihl = 5;
 374                 p.iph.protocol = IPPROTO_IPIP;
 375                 sprintf(p.name, "dvmrp%d", v->vifc_vifi);
 376                 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
 377
 378                 if (ops->ndo_do_ioctl) {
 379                         mm_segment_t oldfs = get_fs();
 380
 381                         set_fs(KERNEL_DS);
 382                         ops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
 383                         set_fs(oldfs);
 384                 }
 385         }
 386 }
 387
 388 static
 389 struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
 390 {
 391         struct net_device  *dev;
 392
 393         dev = __dev_get_by_name(net, "tunl0");
 394
 395         if (dev) {
 396                 const struct net_device_ops *ops = dev->netdev_ops;
 397                 int err;
 398                 struct ifreq ifr;
 399                 struct ip_tunnel_parm p;
 400                 struct in_device  *in_dev;
 401
 402                 memset(&p, 0, sizeof(p));
 403                 p.iph.daddr = v->vifc_rmt_addr.s_addr;
 404                 p.iph.saddr = v->vifc_lcl_addr.s_addr;
 405                 p.iph.version = 4;
 406                 p.iph.ihl = 5;
 407                 p.iph.protocol = IPPROTO_IPIP;
 408                 sprintf(p.name, "dvmrp%d", v->vifc_vifi);
 409                 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
 410
 411                 if (ops->ndo_do_ioctl) {
 412                         mm_segment_t oldfs = get_fs();
 413
 414                         set_fs(KERNEL_DS);
 415                         err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
 416                         set_fs(oldfs);
 417                 } else {
 418                         err = -EOPNOTSUPP;
 419                 }
 420                 dev = NULL;
 421
 422                 if (err == 0 &&
 423                     (dev = __dev_get_by_name(net, p.name)) != NULL) {
 424                         dev->flags |= IFF_MULTICAST;
 425
 426                         in_dev = __in_dev_get_rtnl(dev);
 427                         if (in_dev == NULL)
 428                                 goto failure;
 429
 430                         ipv4_devconf_setall(in_dev);
 431                         neigh_parms_data_state_setall(in_dev->arp_parms);
 432                         IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
 433
 434                         if (dev_open(dev))
 435                                 goto failure;
 436                         dev_hold(dev);
 437                 }
 438         }
 439         return dev;
 440
 441 failure:
 442         /* allow the register to be completed before unregistering. */
 443         rtnl_unlock();
 444         rtnl_lock();
 445
 446         unregister_netdevice(dev);
 447         return NULL;
 448 }
 449
 450 #ifdef CONFIG_IP_PIMSM
 451
 452 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
 453 {
 454         struct net *net = dev_net(dev);
 455         struct mr_table *mrt;
 456         struct flowi4 fl4 = {
 457                 .flowi4_oif     = dev->ifindex,
 458                 .flowi4_iif     = skb->skb_iif,
 459                 .flowi4_mark    = skb->mark,
 460         };
 461         int err;
 462
 463         err = ipmr_fib_lookup(net, &fl4, &mrt);
 464         if (err < 0) {
 465                 kfree_skb(skb);
 466                 return err;
 467         }
 468
 469         read_lock(&mrt_lock);
 470         dev->stats.tx_bytes += skb->len;
 471         dev->stats.tx_packets++;
 472         ipmr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, IGMPMSG_WHOLEPKT);
 473         read_unlock(&mrt_lock);
 474         kfree_skb(skb);
 475         return NETDEV_TX_OK;
 476 }
 477
 478 static const struct net_device_ops reg_vif_netdev_ops = {
 479         .ndo_start_xmit = reg_vif_xmit,
 480 };
 481
 482 static void reg_vif_setup(struct net_device *dev)
 483 {
 484         dev->type               = ARPHRD_PIMREG;
 485         dev->mtu                = ETH_DATA_LEN - sizeof(struct iphdr) - 8;
 486         dev->flags              = IFF_NOARP;
 487         dev->netdev_ops         = &reg_vif_netdev_ops,
 488         dev->destructor         = free_netdev;
 489         dev->features           |= NETIF_F_NETNS_LOCAL;
 490 }
 491
 492 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
 493 {
 494         struct net_device *dev;
 495         struct in_device *in_dev;
 496         char name[IFNAMSIZ];
 497
 498         if (mrt->id == RT_TABLE_DEFAULT)
 499                 sprintf(name, "pimreg");
 500         else
 501                 sprintf(name, "pimreg%u", mrt->id);
 502
 503         dev = alloc_netdev(0, name, reg_vif_setup);
 504
 505         if (dev == NULL)
 506                 return NULL;
 507
 508         dev_net_set(dev, net);
 509
 510         if (register_netdevice(dev)) {
 511                 free_netdev(dev);
 512                 return NULL;
 513         }
 514         dev->iflink = 0;
 515
 516         rcu_read_lock();
 517         in_dev = __in_dev_get_rcu(dev);
 518         if (!in_dev) {
 519                 rcu_read_unlock();
 520                 goto failure;
 521         }
 522
 523         ipv4_devconf_setall(in_dev);
 524         neigh_parms_data_state_setall(in_dev->arp_parms);
 525         IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
 526         rcu_read_unlock();
 527
 528         if (dev_open(dev))
 529                 goto failure;
 530
 531         dev_hold(dev);
 532
 533         return dev;
 534
 535 failure:
 536         /* allow the register to be completed before unregistering. */
 537         rtnl_unlock();
 538         rtnl_lock();
 539
 540         unregister_netdevice(dev);
 541         return NULL;
 542 }
 543 #endif
 544
 545 /**
 546  *      vif_delete - Delete a VIF entry
 547  *      @notify: Set to 1, if the caller is a notifier_call
 548  */
 549
 550 static int vif_delete(struct mr_table *mrt, int vifi, int notify,
 551                       struct list_head *head)
 552 {
 553         struct vif_device *v;
 554         struct net_device *dev;
 555         struct in_device *in_dev;
 556
 557         if (vifi < 0 || vifi >= mrt->maxvif)
 558                 return -EADDRNOTAVAIL;
 559
 560         v = &mrt->vif_table[vifi];
 561
 562         write_lock_bh(&mrt_lock);
 563         dev = v->dev;
 564         v->dev = NULL;
 565
 566         if (!dev) {
 567                 write_unlock_bh(&mrt_lock);
 568                 return -EADDRNOTAVAIL;
 569         }
 570
 571 #ifdef CONFIG_IP_PIMSM
 572         if (vifi == mrt->mroute_reg_vif_num)
 573                 mrt->mroute_reg_vif_num = -1;
 574 #endif
 575
 576         if (vifi + 1 == mrt->maxvif) {
 577                 int tmp;
 578
 579                 for (tmp = vifi - 1; tmp >= 0; tmp--) {
 580                         if (VIF_EXISTS(mrt, tmp))
 581                                 break;
 582                 }
 583                 mrt->maxvif = tmp+1;
 584         }
 585
 586         write_unlock_bh(&mrt_lock);
 587
 588         dev_set_allmulti(dev, -1);
 589
 590         in_dev = __in_dev_get_rtnl(dev);
 591         if (in_dev) {
 592                 IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
 593                 inet_netconf_notify_devconf(dev_net(dev),
 594                                             NETCONFA_MC_FORWARDING,
 595                                             dev->ifindex, &in_dev->cnf);
 596                 ip_rt_multicast_event(in_dev);
 597         }
 598
 599         if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
 600                 unregister_netdevice_queue(dev, head);
 601
 602         dev_put(dev);
 603         return 0;
 604 }
 605
 606 static void ipmr_cache_free_rcu(struct rcu_head *head)
 607 {
 608         struct mfc_cache *c = container_of(head, struct mfc_cache, rcu);
 609
 610         kmem_cache_free(mrt_cachep, c);
 611 }
 612
 613 static inline void ipmr_cache_free(struct mfc_cache *c)
 614 {
 615         call_rcu(&c->rcu, ipmr_cache_free_rcu);
 616 }
 617
 618 /* Destroy an unresolved cache entry, killing queued skbs
 619  * and reporting error to netlink readers.
 620  */
 621
 622 static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
 623 {
 624         struct net *net = read_pnet(&mrt->net);
 625         struct sk_buff *skb;
 626         struct nlmsgerr *e;
 627
 628         atomic_dec(&mrt->cache_resolve_queue_len);
 629
 630         while ((skb = skb_dequeue(&c->mfc_un.unres.unresolved))) {
 631                 if (ip_hdr(skb)->version == 0) {
 632                         struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
 633                         nlh->nlmsg_type = NLMSG_ERROR;
 634                         nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
 635                         skb_trim(skb, nlh->nlmsg_len);
 636                         e = nlmsg_data(nlh);
 637                         e->error = -ETIMEDOUT;
 638                         memset(&e->msg, 0, sizeof(e->msg));
 639
 640                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
 641                 } else {
 642                         kfree_skb(skb);
 643                 }
 644         }
 645
 646         ipmr_cache_free(c);
 647 }
 648
 649
 650 /* Timer process for the unresolved queue. */
 651
 652 static void ipmr_expire_process(unsigned long arg)
 653 {
 654         struct mr_table *mrt = (struct mr_table *)arg;
 655         unsigned long now;
 656         unsigned long expires;
 657         struct mfc_cache *c, *next;
 658
 659         if (!spin_trylock(&mfc_unres_lock)) {
 660                 mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10);
 661                 return;
 662         }
 663
 664         if (list_empty(&mrt->mfc_unres_queue))
 665                 goto out;
 666
 667         now = jiffies;
 668         expires = 10*HZ;
 669
 670         list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
 671                 if (time_after(c->mfc_un.unres.expires, now)) {
 672                         unsigned long interval = c->mfc_un.unres.expires - now;
 673                         if (interval < expires)
 674                                 expires = interval;
 675                         continue;
 676                 }
 677
 678                 list_del(&c->list);
 679                 mroute_netlink_event(mrt, c, RTM_DELROUTE);
 680                 ipmr_destroy_unres(mrt, c);
 681         }
 682
 683         if (!list_empty(&mrt->mfc_unres_queue))
 684                 mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
 685
 686 out:
 687         spin_unlock(&mfc_unres_lock);
 688 }
 689
 690 /* Fill oifs list. It is called under write locked mrt_lock. */
 691
 692 static void ipmr_update_thresholds(struct mr_table *mrt, struct mfc_cache *cache,
 693                                    unsigned char *ttls)
 694 {
 695         int vifi;
 696
 697         cache->mfc_un.res.minvif = MAXVIFS;
 698         cache->mfc_un.res.maxvif = 0;
 699         memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
 700
 701         for (vifi = 0; vifi < mrt->maxvif; vifi++) {
 702                 if (VIF_EXISTS(mrt, vifi) &&
 703                     ttls[vifi] && ttls[vifi] < 255) {
 704                         cache->mfc_un.res.ttls[vifi] = ttls[vifi];
 705                         if (cache->mfc_un.res.minvif > vifi)
 706                                 cache->mfc_un.res.minvif = vifi;
 707                         if (cache->mfc_un.res.maxvif <= vifi)
 708                                 cache->mfc_un.res.maxvif = vifi + 1;
 709                 }
 710         }
 711 }
 712
 713 static int vif_add(struct net *net, struct mr_table *mrt,
 714                    struct vifctl *vifc, int mrtsock)
 715 {
 716         int vifi = vifc->vifc_vifi;
 717         struct vif_device *v = &mrt->vif_table[vifi];
 718         struct net_device *dev;
 719         struct in_device *in_dev;
 720         int err;
 721
 722         /* Is vif busy ? */
 723         if (VIF_EXISTS(mrt, vifi))
 724                 return -EADDRINUSE;
 725
 726         switch (vifc->vifc_flags) {
 727 #ifdef CONFIG_IP_PIMSM
 728         case VIFF_REGISTER:
 729                 /*
 730                  * Special Purpose VIF in PIM
 731                  * All the packets will be sent to the daemon
 732                  */
 733                 if (mrt->mroute_reg_vif_num >= 0)
 734                         return -EADDRINUSE;
 735                 dev = ipmr_reg_vif(net, mrt);
 736                 if (!dev)
 737                         return -ENOBUFS;
 738                 err = dev_set_allmulti(dev, 1);
 739                 if (err) {
 740                         unregister_netdevice(dev);
 741                         dev_put(dev);
 742                         return err;
 743                 }
 744                 break;
 745 #endif
 746         case VIFF_TUNNEL:
 747                 dev = ipmr_new_tunnel(net, vifc);
 748                 if (!dev)
 749                         return -ENOBUFS;
 750                 err = dev_set_allmulti(dev, 1);
 751                 if (err) {
 752                         ipmr_del_tunnel(dev, vifc);
 753                         dev_put(dev);
 754                         return err;
 755                 }
 756                 break;
 757
 758         case VIFF_USE_IFINDEX:
 759         case 0:
 760                 if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
 761                         dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
 762                         if (dev && __in_dev_get_rtnl(dev) == NULL) {
 763                                 dev_put(dev);
 764                                 return -EADDRNOTAVAIL;
 765                         }
 766                 } else {
 767                         dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
 768                 }
 769                 if (!dev)
 770                         return -EADDRNOTAVAIL;
 771                 err = dev_set_allmulti(dev, 1);
 772                 if (err) {
 773                         dev_put(dev);
 774                         return err;
 775                 }
 776                 break;
 777         default:
 778                 return -EINVAL;
 779         }
 780
 781         in_dev = __in_dev_get_rtnl(dev);
 782         if (!in_dev) {
 783                 dev_put(dev);
 784                 return -EADDRNOTAVAIL;
 785         }
 786         IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
 787         inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING, dev->ifindex,
 788                                     &in_dev->cnf);
 789         ip_rt_multicast_event(in_dev);
 790
 791         /* Fill in the VIF structures */
 792
 793         v->rate_limit = vifc->vifc_rate_limit;
 794         v->local = vifc->vifc_lcl_addr.s_addr;
 795         v->remote = vifc->vifc_rmt_addr.s_addr;
 796         v->flags = vifc->vifc_flags;
 797         if (!mrtsock)
 798                 v->flags |= VIFF_STATIC;
 799         v->threshold = vifc->vifc_threshold;
 800         v->bytes_in = 0;
 801         v->bytes_out = 0;
 802         v->pkt_in = 0;
 803         v->pkt_out = 0;
 804         v->link = dev->ifindex;
 805         if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER))
 806                 v->link = dev->iflink;
 807
 808         /* And finish update writing critical data */
 809         write_lock_bh(&mrt_lock);
 810         v->dev = dev;
 811 #ifdef CONFIG_IP_PIMSM
 812         if (v->flags & VIFF_REGISTER)
 813                 mrt->mroute_reg_vif_num = vifi;
 814 #endif
 815         if (vifi+1 > mrt->maxvif)
 816                 mrt->maxvif = vifi+1;
 817         write_unlock_bh(&mrt_lock);
 818         return 0;
 819 }
 820
 821 /* called with rcu_read_lock() */
 822 static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
 823                                          __be32 origin,
 824                                          __be32 mcastgrp)
 825 {
 826         int line = MFC_HASH(mcastgrp, origin);
 827         struct mfc_cache *c;
 828
 829         list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list) {
 830                 if (c->mfc_origin == origin && c->mfc_mcastgrp == mcastgrp)
 831                         return c;
 832         }
 833         return NULL;
 834 }
 835
 836 /* Look for a (*,*,oif) entry */
 837 static struct mfc_cache *ipmr_cache_find_any_parent(struct mr_table *mrt,
 838                                                     int vifi)
 839 {
 840         int line = MFC_HASH(htonl(INADDR_ANY), htonl(INADDR_ANY));
 841         struct mfc_cache *c;
 842
 843         list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list)
 844                 if (c->mfc_origin == htonl(INADDR_ANY) &&
 845                     c->mfc_mcastgrp == htonl(INADDR_ANY) &&
 846                     c->mfc_un.res.ttls[vifi] < 255)
 847                         return c;
 848
 849         return NULL;
 850 }
 851
 852 /* Look for a (*,G) entry */
 853 static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
 854                                              __be32 mcastgrp, int vifi)
 855 {
 856         int line = MFC_HASH(mcastgrp, htonl(INADDR_ANY));
 857         struct mfc_cache *c, *proxy;
 858
 859         if (mcastgrp == htonl(INADDR_ANY))
 860                 goto skip;
 861
 862         list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list)
 863                 if (c->mfc_origin == htonl(INADDR_ANY) &&
 864                     c->mfc_mcastgrp == mcastgrp) {
 865                         if (c->mfc_un.res.ttls[vifi] < 255)
 866                                 return c;
 867
 868                         /* It's ok if the vifi is part of the static tree */
 869                         proxy = ipmr_cache_find_any_parent(mrt,
 870                                                            c->mfc_parent);
 871                         if (proxy && proxy->mfc_un.res.ttls[vifi] < 255)
 872                                 return c;
 873                 }
 874
 875 skip:
 876         return ipmr_cache_find_any_parent(mrt, vifi);
 877 }
 878
 879 /*
 880  *      Allocate a multicast cache entry
 881  */
 882 static struct mfc_cache *ipmr_cache_alloc(void)
 883 {
 884         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
 885
 886         if (c)
 887                 c->mfc_un.res.minvif = MAXVIFS;
 888         return c;
 889 }
 890
 891 static struct mfc_cache *ipmr_cache_alloc_unres(void)
 892 {
 893         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
 894
 895         if (c) {
 896                 skb_queue_head_init(&c->mfc_un.unres.unresolved);
 897                 c->mfc_un.unres.expires = jiffies + 10*HZ;
 898         }
 899         return c;
 900 }
 901
 902 /*
 903  *      A cache entry has gone into a resolved state from queued
 904  */
 905
 906 static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
 907                                struct mfc_cache *uc, struct mfc_cache *c)
 908 {
 909         struct sk_buff *skb;
 910         struct nlmsgerr *e;
 911
 912         /* Play the pending entries through our router */
 913
 914         while ((skb = __skb_dequeue(&uc->mfc_un.unres.unresolved))) {
 915                 if (ip_hdr(skb)->version == 0) {
 916                         struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
 917
 918                         if (__ipmr_fill_mroute(mrt, skb, c, nlmsg_data(nlh)) > 0) {
 919                                 nlh->nlmsg_len = skb_tail_pointer(skb) -
 920                                                  (u8 *)nlh;
 921                         } else {
 922                                 nlh->nlmsg_type = NLMSG_ERROR;
 923                                 nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
 924                                 skb_trim(skb, nlh->nlmsg_len);
 925                                 e = nlmsg_data(nlh);
 926                                 e->error = -EMSGSIZE;
 927                                 memset(&e->msg, 0, sizeof(e->msg));
 928                         }
 929
 930                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
 931                 } else {
 932                         ip_mr_forward(net, mrt, skb, c, 0);
 933                 }
 934         }
 935 }
 936
 937 /*
 938  *      Bounce a cache query up to mrouted. We could use netlink for this but mrouted
 939  *      expects the following bizarre scheme.
 940  *
 941  *      Called under mrt_lock.
 942  */
 943
 944 static int ipmr_cache_report(struct mr_table *mrt,
 945                              struct sk_buff *pkt, vifi_t vifi, int assert)
 946 {
 947         struct sk_buff *skb;
 948         const int ihl = ip_hdrlen(pkt);
 949         struct igmphdr *igmp;
 950         struct igmpmsg *msg;
 951         struct sock *mroute_sk;
 952         int ret;
 953
 954 #ifdef CONFIG_IP_PIMSM
 955         if (assert == IGMPMSG_WHOLEPKT)
 956                 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
 957         else
 958 #endif
 959                 skb = alloc_skb(128, GFP_ATOMIC);
 960
 961         if (!skb)
 962                 return -ENOBUFS;
 963
 964 #ifdef CONFIG_IP_PIMSM
 965         if (assert == IGMPMSG_WHOLEPKT) {
 966                 /* Ugly, but we have no choice with this interface.
 967                  * Duplicate old header, fix ihl, length etc.
 968                  * And all this only to mangle msg->im_msgtype and
 969                  * to set msg->im_mbz to "mbz" :-)
 970                  */
 971                 skb_push(skb, sizeof(struct iphdr));
 972                 skb_reset_network_header(skb);
 973                 skb_reset_transport_header(skb);
 974                 msg = (struct igmpmsg *)skb_network_header(skb);
 975                 memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
 976                 msg->im_msgtype = IGMPMSG_WHOLEPKT;
 977                 msg->im_mbz = 0;
 978                 msg->im_vif = mrt->mroute_reg_vif_num;
 979                 ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
 980                 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
 981                                              sizeof(struct iphdr));
 982         } else
 983 #endif
 984         {
 985
 986         /* Copy the IP header */
 987
 988         skb_set_network_header(skb, skb->len);
 989         skb_put(skb, ihl);
 990         skb_copy_to_linear_data(skb, pkt->data, ihl);
 991         ip_hdr(skb)->protocol = 0;      /* Flag to the kernel this is a route add */
 992         msg = (struct igmpmsg *)skb_network_header(skb);
 993         msg->im_vif = vifi;
 994         skb_dst_set(skb, dst_clone(skb_dst(pkt)));
 995
 996         /* Add our header */
 997
 998         igmp = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
 999         igmp->type      =
1000         msg->im_msgtype = assert;
1001         igmp->code      = 0;
1002         ip_hdr(skb)->tot_len = htons(skb->len);         /* Fix the length */
1003         skb->transport_header = skb->network_header;
1004         }
1005
1006         rcu_read_lock();
1007         mroute_sk = rcu_dereference(mrt->mroute_sk);
1008         if (mroute_sk == NULL) {
1009                 rcu_read_unlock();
1010                 kfree_skb(skb);
1011                 return -EINVAL;
1012         }
1013
1014         /* Deliver to mrouted */
1015
1016         ret = sock_queue_rcv_skb(mroute_sk, skb);
1017         rcu_read_unlock();
1018         if (ret < 0) {
1019                 net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1020                 kfree_skb(skb);
1021         }
1022
1023         return ret;
1024 }
1025
1026 /*
1027  *      Queue a packet for resolution. It gets locked cache entry!
1028  */
1029
1030 static int
1031 ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi, struct sk_buff *skb)
1032 {
1033         bool found = false;
1034         int err;
1035         struct mfc_cache *c;
1036         const struct iphdr *iph = ip_hdr(skb);
1037
1038         spin_lock_bh(&mfc_unres_lock);
1039         list_for_each_entry(c, &mrt->mfc_unres_queue, list) {
1040                 if (c->mfc_mcastgrp == iph->daddr &&
1041                     c->mfc_origin == iph->saddr) {
1042                         found = true;
1043                         break;
1044                 }
1045         }
1046
1047         if (!found) {
1048                 /* Create a new entry if allowable */
1049
1050                 if (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
1051                     (c = ipmr_cache_alloc_unres()) == NULL) {
1052                         spin_unlock_bh(&mfc_unres_lock);
1053
1054                         kfree_skb(skb);
1055                         return -ENOBUFS;
1056                 }
1057
1058                 /* Fill in the new cache entry */
1059
1060                 c->mfc_parent   = -1;
1061                 c->mfc_origin   = iph->saddr;
1062                 c->mfc_mcastgrp = iph->daddr;
1063
1064                 /* Reflect first query at mrouted. */
1065
1066                 err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1067                 if (err < 0) {
1068                         /* If the report failed throw the cache entry
1069                            out - Brad Parker
1070                          */
1071                         spin_unlock_bh(&mfc_unres_lock);
1072
1073                         ipmr_cache_free(c);
1074                         kfree_skb(skb);
1075                         return err;
1076                 }
1077
1078                 atomic_inc(&mrt->cache_resolve_queue_len);
1079                 list_add(&c->list, &mrt->mfc_unres_queue);
1080                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1081
1082                 if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1083                         mod_timer(&mrt->ipmr_expire_timer, c->mfc_un.unres.expires);
1084         }
1085
1086         /* See if we can append the packet */
1087
1088         if (c->mfc_un.unres.unresolved.qlen > 3) {
1089                 kfree_skb(skb);
1090                 err = -ENOBUFS;
1091         } else {
1092                 skb_queue_tail(&c->mfc_un.unres.unresolved, skb);
1093                 err = 0;
1094         }
1095
1096         spin_unlock_bh(&mfc_unres_lock);
1097         return err;
1098 }
1099
1100 /*
1101  *      MFC cache manipulation by user space mroute daemon
1102  */
1103
1104 static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1105 {
1106         int line;
1107         struct mfc_cache *c, *next;
1108
1109         line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1110
1111         list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[line], list) {
1112                 if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1113                     c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr &&
1114                     (parent == -1 || parent == c->mfc_parent)) {
1115                         list_del_rcu(&c->list);
1116                         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1117                         ipmr_cache_free(c);
1118                         return 0;
1119                 }
1120         }
1121         return -ENOENT;
1122 }
1123
1124 static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1125                         struct mfcctl *mfc, int mrtsock, int parent)
1126 {
1127         bool found = false;
1128         int line;
1129         struct mfc_cache *uc, *c;
1130
1131         if (mfc->mfcc_parent >= MAXVIFS)
1132                 return -ENFILE;
1133
1134         line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1135
1136         list_for_each_entry(c, &mrt->mfc_cache_array[line], list) {
1137                 if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1138                     c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr &&
1139                     (parent == -1 || parent == c->mfc_parent)) {
1140                         found = true;
1141                         break;
1142                 }
1143         }
1144
1145         if (found) {
1146                 write_lock_bh(&mrt_lock);
1147                 c->mfc_parent = mfc->mfcc_parent;
1148                 ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1149                 if (!mrtsock)
1150                         c->mfc_flags |= MFC_STATIC;
1151                 write_unlock_bh(&mrt_lock);
1152                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1153                 return 0;
1154         }
1155
1156         if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1157             !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1158                 return -EINVAL;
1159
1160         c = ipmr_cache_alloc();
1161         if (c == NULL)
1162                 return -ENOMEM;
1163
1164         c->mfc_origin = mfc->mfcc_origin.s_addr;
1165         c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1166         c->mfc_parent = mfc->mfcc_parent;
1167         ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1168         if (!mrtsock)
1169                 c->mfc_flags |= MFC_STATIC;
1170
1171         list_add_rcu(&c->list, &mrt->mfc_cache_array[line]);
1172
1173         /*
1174          *      Check to see if we resolved a queued list. If so we
1175          *      need to send on the frames and tidy up.
1176          */
1177         found = false;
1178         spin_lock_bh(&mfc_unres_lock);
1179         list_for_each_entry(uc, &mrt->mfc_unres_queue, list) {
1180                 if (uc->mfc_origin == c->mfc_origin &&
1181                     uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1182                         list_del(&uc->list);
1183                         atomic_dec(&mrt->cache_resolve_queue_len);
1184                         found = true;
1185                         break;
1186                 }
1187         }
1188         if (list_empty(&mrt->mfc_unres_queue))
1189                 del_timer(&mrt->ipmr_expire_timer);
1190         spin_unlock_bh(&mfc_unres_lock);
1191
1192         if (found) {
1193                 ipmr_cache_resolve(net, mrt, uc, c);
1194                 ipmr_cache_free(uc);
1195         }
1196         mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1197         return 0;
1198 }
1199
1200 /*
1201  *      Close the multicast socket, and clear the vif tables etc
1202  */
1203
1204 static void mroute_clean_tables(struct mr_table *mrt)
1205 {
1206         int i;
1207         LIST_HEAD(list);
1208         struct mfc_cache *c, *next;
1209
1210         /* Shut down all active vif entries */
1211
1212         for (i = 0; i < mrt->maxvif; i++) {
1213                 if (!(mrt->vif_table[i].flags & VIFF_STATIC))
1214                         vif_delete(mrt, i, 0, &list);
1215         }
1216         unregister_netdevice_many(&list);
1217
1218         /* Wipe the cache */
1219
1220         for (i = 0; i < MFC_LINES; i++) {
1221                 list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[i], list) {
1222                         if (c->mfc_flags & MFC_STATIC)
1223                                 continue;
1224                         list_del_rcu(&c->list);
1225                         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1226                         ipmr_cache_free(c);
1227                 }
1228         }
1229
1230         if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1231                 spin_lock_bh(&mfc_unres_lock);
1232                 list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
1233                         list_del(&c->list);
1234                         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1235                         ipmr_destroy_unres(mrt, c);
1236                 }
1237                 spin_unlock_bh(&mfc_unres_lock);
1238         }
1239 }
1240
1241 /* called from ip_ra_control(), before an RCU grace period,
1242  * we dont need to call synchronize_rcu() here
1243  */
1244 static void mrtsock_destruct(struct sock *sk)
1245 {
1246         struct net *net = sock_net(sk);
1247         struct mr_table *mrt;
1248
1249         rtnl_lock();
1250         ipmr_for_each_table(mrt, net) {
1251                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1252                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1253                         inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
1254                                                     NETCONFA_IFINDEX_ALL,
1255                                                     net->ipv4.devconf_all);
1256                         RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1257                         mroute_clean_tables(mrt);
1258                 }
1259         }
1260         rtnl_unlock();
1261 }
1262
1263 /*
1264  *      Socket options and virtual interface manipulation. The whole
1265  *      virtual interface system is a complete heap, but unfortunately
1266  *      that's how BSD mrouted happens to think. Maybe one day with a proper
1267  *      MOSPF/PIM router set up we can clean this up.
1268  */
1269
1270 int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsigned int optlen)
1271 {
1272         int ret, parent = 0;
1273         struct vifctl vif;
1274         struct mfcctl mfc;
1275         struct net *net = sock_net(sk);
1276         struct mr_table *mrt;
1277
1278         if (sk->sk_type != SOCK_RAW ||
1279             inet_sk(sk)->inet_num != IPPROTO_IGMP)
1280                 return -EOPNOTSUPP;
1281
1282         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1283         if (mrt == NULL)
1284                 return -ENOENT;
1285
1286         if (optname != MRT_INIT) {
1287                 if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1288                     !ns_capable(net->user_ns, CAP_NET_ADMIN))
1289                         return -EACCES;
1290         }
1291
1292         switch (optname) {
1293         case MRT_INIT:
1294                 if (optlen != sizeof(int))
1295                         return -EINVAL;
1296
1297                 rtnl_lock();
1298                 if (rtnl_dereference(mrt->mroute_sk)) {
1299                         rtnl_unlock();
1300                         return -EADDRINUSE;
1301                 }
1302
1303                 ret = ip_ra_control(sk, 1, mrtsock_destruct);
1304                 if (ret == 0) {
1305                         rcu_assign_pointer(mrt->mroute_sk, sk);
1306                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1307                         inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
1308                                                     NETCONFA_IFINDEX_ALL,
1309                                                     net->ipv4.devconf_all);
1310                 }
1311                 rtnl_unlock();
1312                 return ret;
1313         case MRT_DONE:
1314                 if (sk != rcu_access_pointer(mrt->mroute_sk))
1315                         return -EACCES;
1316                 return ip_ra_control(sk, 0, NULL);
1317         case MRT_ADD_VIF:
1318         case MRT_DEL_VIF:
1319                 if (optlen != sizeof(vif))
1320                         return -EINVAL;
1321                 if (copy_from_user(&vif, optval, sizeof(vif)))
1322                         return -EFAULT;
1323                 if (vif.vifc_vifi >= MAXVIFS)
1324                         return -ENFILE;
1325                 rtnl_lock();
1326                 if (optname == MRT_ADD_VIF) {
1327                         ret = vif_add(net, mrt, &vif,
1328                                       sk == rtnl_dereference(mrt->mroute_sk));
1329                 } else {
1330                         ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1331                 }
1332                 rtnl_unlock();
1333                 return ret;
1334
1335                 /*
1336                  *      Manipulate the forwarding caches. These live
1337                  *      in a sort of kernel/user symbiosis.
1338                  */
1339         case MRT_ADD_MFC:
1340         case MRT_DEL_MFC:
1341                 parent = -1;
1342         case MRT_ADD_MFC_PROXY:
1343         case MRT_DEL_MFC_PROXY:
1344                 if (optlen != sizeof(mfc))
1345                         return -EINVAL;
1346                 if (copy_from_user(&mfc, optval, sizeof(mfc)))
1347                         return -EFAULT;
1348                 if (parent == 0)
1349                         parent = mfc.mfcc_parent;
1350                 rtnl_lock();
1351                 if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1352                         ret = ipmr_mfc_delete(mrt, &mfc, parent);
1353                 else
1354                         ret = ipmr_mfc_add(net, mrt, &mfc,
1355                                            sk == rtnl_dereference(mrt->mroute_sk),
1356                                            parent);
1357                 rtnl_unlock();
1358                 return ret;
1359                 /*
1360                  *      Control PIM assert.
1361                  */
1362         case MRT_ASSERT:
1363         {
1364                 int v;
1365                 if (optlen != sizeof(v))
1366                         return -EINVAL;
1367                 if (get_user(v, (int __user *)optval))
1368                         return -EFAULT;
1369                 mrt->mroute_do_assert = v;
1370                 return 0;
1371         }
1372 #ifdef CONFIG_IP_PIMSM
1373         case MRT_PIM:
1374         {
1375                 int v;
1376
1377                 if (optlen != sizeof(v))
1378                         return -EINVAL;
1379                 if (get_user(v, (int __user *)optval))
1380                         return -EFAULT;
1381                 v = !!v;
1382
1383                 rtnl_lock();
1384                 ret = 0;
1385                 if (v != mrt->mroute_do_pim) {
1386                         mrt->mroute_do_pim = v;
1387                         mrt->mroute_do_assert = v;
1388                 }
1389                 rtnl_unlock();
1390                 return ret;
1391         }
1392 #endif
1393 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
1394         case MRT_TABLE:
1395         {
1396                 u32 v;
1397
1398                 if (optlen != sizeof(u32))
1399                         return -EINVAL;
1400                 if (get_user(v, (u32 __user *)optval))
1401                         return -EFAULT;
1402
1403                 /* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) */
1404                 if (v != RT_TABLE_DEFAULT && v >= 1000000000)
1405                         return -EINVAL;
1406
1407                 rtnl_lock();
1408                 ret = 0;
1409                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1410                         ret = -EBUSY;
1411                 } else {
1412                         if (!ipmr_new_table(net, v))
1413                                 ret = -ENOMEM;
1414                         else
1415                                 raw_sk(sk)->ipmr_table = v;
1416                 }
1417                 rtnl_unlock();
1418                 return ret;
1419         }
1420 #endif
1421         /*
1422          *      Spurious command, or MRT_VERSION which you cannot
1423          *      set.
1424          */
1425         default:
1426                 return -ENOPROTOOPT;
1427         }
1428 }
1429
1430 /*
1431  *      Getsock opt support for the multicast routing system.
1432  */
1433
1434 int ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen)
1435 {
1436         int olr;
1437         int val;
1438         struct net *net = sock_net(sk);
1439         struct mr_table *mrt;
1440
1441         if (sk->sk_type != SOCK_RAW ||
1442             inet_sk(sk)->inet_num != IPPROTO_IGMP)
1443                 return -EOPNOTSUPP;
1444
1445         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1446         if (mrt == NULL)
1447                 return -ENOENT;
1448
1449         if (optname != MRT_VERSION &&
1450 #ifdef CONFIG_IP_PIMSM
1451            optname != MRT_PIM &&
1452 #endif
1453            optname != MRT_ASSERT)
1454                 return -ENOPROTOOPT;
1455
1456         if (get_user(olr, optlen))
1457                 return -EFAULT;
1458
1459         olr = min_t(unsigned int, olr, sizeof(int));
1460         if (olr < 0)
1461                 return -EINVAL;
1462
1463         if (put_user(olr, optlen))
1464                 return -EFAULT;
1465         if (optname == MRT_VERSION)
1466                 val = 0x0305;
1467 #ifdef CONFIG_IP_PIMSM
1468         else if (optname == MRT_PIM)
1469                 val = mrt->mroute_do_pim;
1470 #endif
1471         else
1472                 val = mrt->mroute_do_assert;
1473         if (copy_to_user(optval, &val, olr))
1474                 return -EFAULT;
1475         return 0;
1476 }
1477
1478 /*
1479  *      The IP multicast ioctl support routines.
1480  */
1481
1482 int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
1483 {
1484         struct sioc_sg_req sr;
1485         struct sioc_vif_req vr;
1486         struct vif_device *vif;
1487         struct mfc_cache *c;
1488         struct net *net = sock_net(sk);
1489         struct mr_table *mrt;
1490
1491         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1492         if (mrt == NULL)
1493                 return -ENOENT;
1494
1495         switch (cmd) {
1496         case SIOCGETVIFCNT:
1497                 if (copy_from_user(&vr, arg, sizeof(vr)))
1498                         return -EFAULT;
1499                 if (vr.vifi >= mrt->maxvif)
1500                         return -EINVAL;
1501                 read_lock(&mrt_lock);
1502                 vif = &mrt->vif_table[vr.vifi];
1503                 if (VIF_EXISTS(mrt, vr.vifi)) {
1504                         vr.icount = vif->pkt_in;
1505                         vr.ocount = vif->pkt_out;
1506                         vr.ibytes = vif->bytes_in;
1507                         vr.obytes = vif->bytes_out;
1508                         read_unlock(&mrt_lock);
1509
1510                         if (copy_to_user(arg, &vr, sizeof(vr)))
1511                                 return -EFAULT;
1512                         return 0;
1513                 }
1514                 read_unlock(&mrt_lock);
1515                 return -EADDRNOTAVAIL;
1516         case SIOCGETSGCNT:
1517                 if (copy_from_user(&sr, arg, sizeof(sr)))
1518                         return -EFAULT;
1519
1520                 rcu_read_lock();
1521                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1522                 if (c) {
1523                         sr.pktcnt = c->mfc_un.res.pkt;
1524                         sr.bytecnt = c->mfc_un.res.bytes;
1525                         sr.wrong_if = c->mfc_un.res.wrong_if;
1526                         rcu_read_unlock();
1527
1528                         if (copy_to_user(arg, &sr, sizeof(sr)))
1529                                 return -EFAULT;
1530                         return 0;
1531                 }
1532                 rcu_read_unlock();
1533                 return -EADDRNOTAVAIL;
1534         default:
1535                 return -ENOIOCTLCMD;
1536         }
1537 }
1538
1539 #ifdef CONFIG_COMPAT
1540 struct compat_sioc_sg_req {
1541         struct in_addr src;
1542         struct in_addr grp;
1543         compat_ulong_t pktcnt;
1544         compat_ulong_t bytecnt;
1545         compat_ulong_t wrong_if;
1546 };
1547
1548 struct compat_sioc_vif_req {
1549         vifi_t  vifi;           /* Which iface */
1550         compat_ulong_t icount;
1551         compat_ulong_t ocount;
1552         compat_ulong_t ibytes;
1553         compat_ulong_t obytes;
1554 };
1555
1556 int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1557 {
1558         struct compat_sioc_sg_req sr;
1559         struct compat_sioc_vif_req vr;
1560         struct vif_device *vif;
1561         struct mfc_cache *c;
1562         struct net *net = sock_net(sk);
1563         struct mr_table *mrt;
1564
1565         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1566         if (mrt == NULL)
1567                 return -ENOENT;
1568
1569         switch (cmd) {
1570         case SIOCGETVIFCNT:
1571                 if (copy_from_user(&vr, arg, sizeof(vr)))
1572                         return -EFAULT;
1573                 if (vr.vifi >= mrt->maxvif)
1574                         return -EINVAL;
1575                 read_lock(&mrt_lock);
1576                 vif = &mrt->vif_table[vr.vifi];
1577                 if (VIF_EXISTS(mrt, vr.vifi)) {
1578                         vr.icount = vif->pkt_in;
1579                         vr.ocount = vif->pkt_out;
1580                         vr.ibytes = vif->bytes_in;
1581                         vr.obytes = vif->bytes_out;
1582                         read_unlock(&mrt_lock);
1583
1584                         if (copy_to_user(arg, &vr, sizeof(vr)))
1585                                 return -EFAULT;
1586                         return 0;
1587                 }
1588                 read_unlock(&mrt_lock);
1589                 return -EADDRNOTAVAIL;
1590         case SIOCGETSGCNT:
1591                 if (copy_from_user(&sr, arg, sizeof(sr)))
1592                         return -EFAULT;
1593
1594                 rcu_read_lock();
1595                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1596                 if (c) {
1597                         sr.pktcnt = c->mfc_un.res.pkt;
1598                         sr.bytecnt = c->mfc_un.res.bytes;
1599                         sr.wrong_if = c->mfc_un.res.wrong_if;
1600                         rcu_read_unlock();
1601
1602                         if (copy_to_user(arg, &sr, sizeof(sr)))
1603                                 return -EFAULT;
1604                         return 0;
1605                 }
1606                 rcu_read_unlock();
1607                 return -EADDRNOTAVAIL;
1608         default:
1609                 return -ENOIOCTLCMD;
1610         }
1611 }
1612 #endif
1613
1614
1615 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1616 {
1617         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1618         struct net *net = dev_net(dev);
1619         struct mr_table *mrt;
1620         struct vif_device *v;
1621         int ct;
1622
1623         if (event != NETDEV_UNREGISTER)
1624                 return NOTIFY_DONE;
1625
1626         ipmr_for_each_table(mrt, net) {
1627                 v = &mrt->vif_table[0];
1628                 for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1629                         if (v->dev == dev)
1630                                 vif_delete(mrt, ct, 1, NULL);
1631                 }
1632         }
1633         return NOTIFY_DONE;
1634 }
1635
1636
1637 static struct notifier_block ip_mr_notifier = {
1638         .notifier_call = ipmr_device_event,
1639 };
1640
1641 /*
1642  *      Encapsulate a packet by attaching a valid IPIP header to it.
1643  *      This avoids tunnel drivers and other mess and gives us the speed so
1644  *      important for multicast video.
1645  */
1646
1647 static void ip_encap(struct sk_buff *skb, __be32 saddr, __be32 daddr)
1648 {
1649         struct iphdr *iph;
1650         const struct iphdr *old_iph = ip_hdr(skb);
1651
1652         skb_push(skb, sizeof(struct iphdr));
1653         skb->transport_header = skb->network_header;
1654         skb_reset_network_header(skb);
1655         iph = ip_hdr(skb);
1656
1657         iph->version    =       4;
1658         iph->tos        =       old_iph->tos;
1659         iph->ttl        =       old_iph->ttl;
1660         iph->frag_off   =       0;
1661         iph->daddr      =       daddr;
1662         iph->saddr      =       saddr;
1663         iph->protocol   =       IPPROTO_IPIP;
1664         iph->ihl        =       5;
1665         iph->tot_len    =       htons(skb->len);
1666         ip_select_ident(skb, skb_dst(skb), NULL);
1667         ip_send_check(iph);
1668
1669         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1670         nf_reset(skb);
1671 }
1672
1673 static inline int ipmr_forward_finish(struct sk_buff *skb)
1674 {
1675         struct ip_options *opt = &(IPCB(skb)->opt);
1676
1677         IP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTFORWDATAGRAMS);
1678         IP_ADD_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTOCTETS, skb->len);
1679
1680         if (unlikely(opt->optlen))
1681                 ip_forward_options(skb);
1682
1683         return dst_output(skb);
1684 }
1685
1686 /*
1687  *      Processing handlers for ipmr_forward
1688  */
1689
1690 static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1691                             struct sk_buff *skb, struct mfc_cache *c, int vifi)
1692 {
1693         const struct iphdr *iph = ip_hdr(skb);
1694         struct vif_device *vif = &mrt->vif_table[vifi];
1695         struct net_device *dev;
1696         struct rtable *rt;
1697         struct flowi4 fl4;
1698         int    encap = 0;
1699
1700         if (vif->dev == NULL)
1701                 goto out_free;
1702
1703 #ifdef CONFIG_IP_PIMSM
1704         if (vif->flags & VIFF_REGISTER) {
1705                 vif->pkt_out++;
1706                 vif->bytes_out += skb->len;
1707                 vif->dev->stats.tx_bytes += skb->len;
1708                 vif->dev->stats.tx_packets++;
1709                 ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1710                 goto out_free;
1711         }
1712 #endif
1713
1714         if (vif->flags & VIFF_TUNNEL) {
1715                 rt = ip_route_output_ports(net, &fl4, NULL,
1716                                            vif->remote, vif->local,
1717                                            0, 0,
1718                                            IPPROTO_IPIP,
1719                                            RT_TOS(iph->tos), vif->link);
1720                 if (IS_ERR(rt))
1721                         goto out_free;
1722                 encap = sizeof(struct iphdr);
1723         } else {
1724                 rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1725                                            0, 0,
1726                                            IPPROTO_IPIP,
1727                                            RT_TOS(iph->tos), vif->link);
1728                 if (IS_ERR(rt))
1729                         goto out_free;
1730         }
1731
1732         dev = rt->dst.dev;
1733
1734         if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1735                 /* Do not fragment multicasts. Alas, IPv4 does not
1736                  * allow to send ICMP, so that packets will disappear
1737                  * to blackhole.
1738                  */
1739
1740                 IP_INC_STATS_BH(dev_net(dev), IPSTATS_MIB_FRAGFAILS);
1741                 ip_rt_put(rt);
1742                 goto out_free;
1743         }
1744
1745         encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1746
1747         if (skb_cow(skb, encap)) {
1748                 ip_rt_put(rt);
1749                 goto out_free;
1750         }
1751
1752         vif->pkt_out++;
1753         vif->bytes_out += skb->len;
1754
1755         skb_dst_drop(skb);
1756         skb_dst_set(skb, &rt->dst);
1757         ip_decrease_ttl(ip_hdr(skb));
1758
1759         /* FIXME: forward and output firewalls used to be called here.
1760          * What do we do with netfilter? -- RR
1761          */
1762         if (vif->flags & VIFF_TUNNEL) {
1763                 ip_encap(skb, vif->local, vif->remote);
1764                 /* FIXME: extra output firewall step used to be here. --RR */
1765                 vif->dev->stats.tx_packets++;
1766                 vif->dev->stats.tx_bytes += skb->len;
1767         }
1768
1769         IPCB(skb)->flags |= IPSKB_FORWARDED;
1770
1771         /*
1772          * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1773          * not only before forwarding, but after forwarding on all output
1774          * interfaces. It is clear, if mrouter runs a multicasting
1775          * program, it should receive packets not depending to what interface
1776          * program is joined.
1777          * If we will not make it, the program will have to join on all
1778          * interfaces. On the other hand, multihoming host (or router, but
1779          * not mrouter) cannot join to more than one interface - it will
1780          * result in receiving multiple packets.
1781          */
1782         NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD, skb, skb->dev, dev,
1783                 ipmr_forward_finish);
1784         return;
1785
1786 out_free:
1787         kfree_skb(skb);
1788 }
1789
1790 static int ipmr_find_vif(struct mr_table *mrt, struct net_device *dev)
1791 {
1792         int ct;
1793
1794         for (ct = mrt->maxvif-1; ct >= 0; ct--) {
1795                 if (mrt->vif_table[ct].dev == dev)
1796                         break;
1797         }
1798         return ct;
1799 }
1800
1801 /* "local" means that we should preserve one skb (for local delivery) */
1802
1803 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1804                           struct sk_buff *skb, struct mfc_cache *cache,
1805                           int local)
1806 {
1807         int psend = -1;
1808         int vif, ct;
1809         int true_vifi = ipmr_find_vif(mrt, skb->dev);
1810
1811         vif = cache->mfc_parent;
1812         cache->mfc_un.res.pkt++;
1813         cache->mfc_un.res.bytes += skb->len;
1814
1815         if (cache->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1816                 struct mfc_cache *cache_proxy;
1817
1818                 /* For an (*,G) entry, we only check that the incomming
1819                  * interface is part of the static tree.
1820                  */
1821                 cache_proxy = ipmr_cache_find_any_parent(mrt, vif);
1822                 if (cache_proxy &&
1823                     cache_proxy->mfc_un.res.ttls[true_vifi] < 255)
1824                         goto forward;
1825         }
1826
1827         /*
1828          * Wrong interface: drop packet and (maybe) send PIM assert.
1829          */
1830         if (mrt->vif_table[vif].dev != skb->dev) {
1831                 if (rt_is_output_route(skb_rtable(skb))) {
1832                         /* It is our own packet, looped back.
1833                          * Very complicated situation...
1834                          *
1835                          * The best workaround until routing daemons will be
1836                          * fixed is not to redistribute packet, if it was
1837                          * send through wrong interface. It means, that
1838                          * multicast applications WILL NOT work for
1839                          * (S,G), which have default multicast route pointing
1840                          * to wrong oif. In any case, it is not a good
1841                          * idea to use multicasting applications on router.
1842                          */
1843                         goto dont_forward;
1844                 }
1845
1846                 cache->mfc_un.res.wrong_if++;
1847
1848                 if (true_vifi >= 0 && mrt->mroute_do_assert &&
1849                     /* pimsm uses asserts, when switching from RPT to SPT,
1850                      * so that we cannot check that packet arrived on an oif.
1851                      * It is bad, but otherwise we would need to move pretty
1852                      * large chunk of pimd to kernel. Ough... --ANK
1853                      */
1854                     (mrt->mroute_do_pim ||
1855                      cache->mfc_un.res.ttls[true_vifi] < 255) &&
1856                     time_after(jiffies,
1857                                cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) {
1858                         cache->mfc_un.res.last_assert = jiffies;
1859                         ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
1860                 }
1861                 goto dont_forward;
1862         }
1863
1864 forward:
1865         mrt->vif_table[vif].pkt_in++;
1866         mrt->vif_table[vif].bytes_in += skb->len;
1867
1868         /*
1869          *      Forward the frame
1870          */
1871         if (cache->mfc_origin == htonl(INADDR_ANY) &&
1872             cache->mfc_mcastgrp == htonl(INADDR_ANY)) {
1873                 if (true_vifi >= 0 &&
1874                     true_vifi != cache->mfc_parent &&
1875                     ip_hdr(skb)->ttl >
1876                                 cache->mfc_un.res.ttls[cache->mfc_parent]) {
1877                         /* It's an (*,*) entry and the packet is not coming from
1878                          * the upstream: forward the packet to the upstream
1879                          * only.
1880                          */
1881                         psend = cache->mfc_parent;
1882                         goto last_forward;
1883                 }
1884                 goto dont_forward;
1885         }
1886         for (ct = cache->mfc_un.res.maxvif - 1;
1887              ct >= cache->mfc_un.res.minvif; ct--) {
1888                 /* For (*,G) entry, don't forward to the incoming interface */
1889                 if ((cache->mfc_origin != htonl(INADDR_ANY) ||
1890                      ct != true_vifi) &&
1891                     ip_hdr(skb)->ttl > cache->mfc_un.res.ttls[ct]) {
1892                         if (psend != -1) {
1893                                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1894
1895                                 if (skb2)
1896                                         ipmr_queue_xmit(net, mrt, skb2, cache,
1897                                                         psend);
1898                         }
1899                         psend = ct;
1900                 }
1901         }
1902 last_forward:
1903         if (psend != -1) {
1904                 if (local) {
1905                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1906
1907                         if (skb2)
1908                                 ipmr_queue_xmit(net, mrt, skb2, cache, psend);
1909                 } else {
1910                         ipmr_queue_xmit(net, mrt, skb, cache, psend);
1911                         return;
1912                 }
1913         }
1914
1915 dont_forward:
1916         if (!local)
1917                 kfree_skb(skb);
1918 }
1919
1920 static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
1921 {
1922         struct rtable *rt = skb_rtable(skb);
1923         struct iphdr *iph = ip_hdr(skb);
1924         struct flowi4 fl4 = {
1925                 .daddr = iph->daddr,
1926                 .saddr = iph->saddr,
1927                 .flowi4_tos = RT_TOS(iph->tos),
1928                 .flowi4_oif = (rt_is_output_route(rt) ?
1929                                skb->dev->ifindex : 0),
1930                 .flowi4_iif = (rt_is_output_route(rt) ?
1931                                LOOPBACK_IFINDEX :
1932                                skb->dev->ifindex),
1933                 .flowi4_mark = skb->mark,
1934         };
1935         struct mr_table *mrt;
1936         int err;
1937
1938         err = ipmr_fib_lookup(net, &fl4, &mrt);
1939         if (err)
1940                 return ERR_PTR(err);
1941         return mrt;
1942 }
1943
1944 /*
1945  *      Multicast packets for forwarding arrive here
1946  *      Called with rcu_read_lock();
1947  */
1948
1949 int ip_mr_input(struct sk_buff *skb)
1950 {
1951         struct mfc_cache *cache;
1952         struct net *net = dev_net(skb->dev);
1953         int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
1954         struct mr_table *mrt;
1955
1956         /* Packet is looped back after forward, it should not be
1957          * forwarded second time, but still can be delivered locally.
1958          */
1959         if (IPCB(skb)->flags & IPSKB_FORWARDED)
1960                 goto dont_forward;
1961
1962         mrt = ipmr_rt_fib_lookup(net, skb);
1963         if (IS_ERR(mrt)) {
1964                 kfree_skb(skb);
1965                 return PTR_ERR(mrt);
1966         }
1967         if (!local) {
1968                 if (IPCB(skb)->opt.router_alert) {
1969                         if (ip_call_ra_chain(skb))
1970                                 return 0;
1971                 } else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
1972                         /* IGMPv1 (and broken IGMPv2 implementations sort of
1973                          * Cisco IOS <= 11.2(8)) do not put router alert
1974                          * option to IGMP packets destined to routable
1975                          * groups. It is very bad, because it means
1976                          * that we can forward NO IGMP messages.
1977                          */
1978                         struct sock *mroute_sk;
1979
1980                         mroute_sk = rcu_dereference(mrt->mroute_sk);
1981                         if (mroute_sk) {
1982                                 nf_reset(skb);
1983                                 raw_rcv(mroute_sk, skb);
1984                                 return 0;
1985                         }
1986                     }
1987         }
1988
1989         /* already under rcu_read_lock() */
1990         cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
1991         if (cache == NULL) {
1992                 int vif = ipmr_find_vif(mrt, skb->dev);
1993
1994                 if (vif >= 0)
1995                         cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
1996                                                     vif);
1997         }
1998
1999         /*
2000          *      No usable cache entry
2001          */
2002         if (cache == NULL) {
2003                 int vif;
2004
2005                 if (local) {
2006                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2007                         ip_local_deliver(skb);
2008                         if (skb2 == NULL)
2009                                 return -ENOBUFS;
2010                         skb = skb2;
2011                 }
2012
2013                 read_lock(&mrt_lock);
2014                 vif = ipmr_find_vif(mrt, skb->dev);
2015                 if (vif >= 0) {
2016                         int err2 = ipmr_cache_unresolved(mrt, vif, skb);
2017                         read_unlock(&mrt_lock);
2018
2019                         return err2;
2020                 }
2021                 read_unlock(&mrt_lock);
2022                 kfree_skb(skb);
2023                 return -ENODEV;
2024         }
2025
2026         read_lock(&mrt_lock);
2027         ip_mr_forward(net, mrt, skb, cache, local);
2028         read_unlock(&mrt_lock);
2029
2030         if (local)
2031                 return ip_local_deliver(skb);
2032
2033         return 0;
2034
2035 dont_forward:
2036         if (local)
2037                 return ip_local_deliver(skb);
2038         kfree_skb(skb);
2039         return 0;
2040 }
2041
2042 #ifdef CONFIG_IP_PIMSM
2043 /* called with rcu_read_lock() */
2044 static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
2045                      unsigned int pimlen)
2046 {
2047         struct net_device *reg_dev = NULL;
2048         struct iphdr *encap;
2049
2050         encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
2051         /*
2052          * Check that:
2053          * a. packet is really sent to a multicast group
2054          * b. packet is not a NULL-REGISTER
2055          * c. packet is not truncated
2056          */
2057         if (!ipv4_is_multicast(encap->daddr) ||
2058             encap->tot_len == 0 ||
2059             ntohs(encap->tot_len) + pimlen > skb->len)
2060                 return 1;
2061
2062         read_lock(&mrt_lock);
2063         if (mrt->mroute_reg_vif_num >= 0)
2064                 reg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
2065         read_unlock(&mrt_lock);
2066
2067         if (reg_dev == NULL)
2068                 return 1;
2069
2070         skb->mac_header = skb->network_header;
2071         skb_pull(skb, (u8 *)encap - skb->data);
2072         skb_reset_network_header(skb);
2073         skb->protocol = htons(ETH_P_IP);
2074         skb->ip_summed = CHECKSUM_NONE;
2075
2076         skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
2077
2078         netif_rx(skb);
2079
2080         return NET_RX_SUCCESS;
2081 }
2082 #endif
2083
2084 #ifdef CONFIG_IP_PIMSM_V1
2085 /*
2086  * Handle IGMP messages of PIMv1
2087  */
2088
2089 int pim_rcv_v1(struct sk_buff *skb)
2090 {
2091         struct igmphdr *pim;
2092         struct net *net = dev_net(skb->dev);
2093         struct mr_table *mrt;
2094
2095         if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2096                 goto drop;
2097
2098         pim = igmp_hdr(skb);
2099
2100         mrt = ipmr_rt_fib_lookup(net, skb);
2101         if (IS_ERR(mrt))
2102                 goto drop;
2103         if (!mrt->mroute_do_pim ||
2104             pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
2105                 goto drop;
2106
2107         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2108 drop:
2109                 kfree_skb(skb);
2110         }
2111         return 0;
2112 }
2113 #endif
2114
2115 #ifdef CONFIG_IP_PIMSM_V2
2116 static int pim_rcv(struct sk_buff *skb)
2117 {
2118         struct pimreghdr *pim;
2119         struct net *net = dev_net(skb->dev);
2120         struct mr_table *mrt;
2121
2122         if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2123                 goto drop;
2124
2125         pim = (struct pimreghdr *)skb_transport_header(skb);
2126         if (pim->type != ((PIM_VERSION << 4) | (PIM_REGISTER)) ||
2127             (pim->flags & PIM_NULL_REGISTER) ||
2128             (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
2129              csum_fold(skb_checksum(skb, 0, skb->len, 0))))
2130                 goto drop;
2131
2132         mrt = ipmr_rt_fib_lookup(net, skb);
2133         if (IS_ERR(mrt))
2134                 goto drop;
2135         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2136 drop:
2137                 kfree_skb(skb);
2138         }
2139         return 0;
2140 }
2141 #endif
2142
2143 static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2144                               struct mfc_cache *c, struct rtmsg *rtm)
2145 {
2146         int ct;
2147         struct rtnexthop *nhp;
2148         struct nlattr *mp_attr;
2149         struct rta_mfc_stats mfcs;
2150
2151         /* If cache is unresolved, don't try to parse IIF and OIF */
2152         if (c->mfc_parent >= MAXVIFS)
2153                 return -ENOENT;
2154
2155         if (VIF_EXISTS(mrt, c->mfc_parent) &&
2156             nla_put_u32(skb, RTA_IIF, mrt->vif_table[c->mfc_parent].dev->ifindex) < 0)
2157                 return -EMSGSIZE;
2158
2159         if (!(mp_attr = nla_nest_start(skb, RTA_MULTIPATH)))
2160                 return -EMSGSIZE;
2161
2162         for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
2163                 if (VIF_EXISTS(mrt, ct) && c->mfc_un.res.ttls[ct] < 255) {
2164                         if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp)))) {
2165                                 nla_nest_cancel(skb, mp_attr);
2166                                 return -EMSGSIZE;
2167                         }
2168
2169                         nhp->rtnh_flags = 0;
2170                         nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
2171                         nhp->rtnh_ifindex = mrt->vif_table[ct].dev->ifindex;
2172                         nhp->rtnh_len = sizeof(*nhp);
2173                 }
2174         }
2175
2176         nla_nest_end(skb, mp_attr);
2177
2178         mfcs.mfcs_packets = c->mfc_un.res.pkt;
2179         mfcs.mfcs_bytes = c->mfc_un.res.bytes;
2180         mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
2181         if (nla_put(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs) < 0)
2182                 return -EMSGSIZE;
2183
2184         rtm->rtm_type = RTN_MULTICAST;
2185         return 1;
2186 }
2187
2188 int ipmr_get_route(struct net *net, struct sk_buff *skb,
2189                    __be32 saddr, __be32 daddr,
2190                    struct rtmsg *rtm, int nowait)
2191 {
2192         struct mfc_cache *cache;
2193         struct mr_table *mrt;
2194         int err;
2195
2196         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2197         if (mrt == NULL)
2198                 return -ENOENT;
2199
2200         rcu_read_lock();
2201         cache = ipmr_cache_find(mrt, saddr, daddr);
2202         if (cache == NULL && skb->dev) {
2203                 int vif = ipmr_find_vif(mrt, skb->dev);
2204
2205                 if (vif >= 0)
2206                         cache = ipmr_cache_find_any(mrt, daddr, vif);
2207         }
2208         if (cache == NULL) {
2209                 struct sk_buff *skb2;
2210                 struct iphdr *iph;
2211                 struct net_device *dev;
2212                 int vif = -1;
2213
2214                 if (nowait) {
2215                         rcu_read_unlock();
2216                         return -EAGAIN;
2217                 }
2218
2219                 dev = skb->dev;
2220                 read_lock(&mrt_lock);
2221                 if (dev)
2222                         vif = ipmr_find_vif(mrt, dev);
2223                 if (vif < 0) {
2224                         read_unlock(&mrt_lock);
2225                         rcu_read_unlock();
2226                         return -ENODEV;
2227                 }
2228                 skb2 = skb_clone(skb, GFP_ATOMIC);
2229                 if (!skb2) {
2230                         read_unlock(&mrt_lock);
2231                         rcu_read_unlock();
2232                         return -ENOMEM;
2233                 }
2234
2235                 skb_push(skb2, sizeof(struct iphdr));
2236                 skb_reset_network_header(skb2);
2237                 iph = ip_hdr(skb2);
2238                 iph->ihl = sizeof(struct iphdr) >> 2;
2239                 iph->saddr = saddr;
2240                 iph->daddr = daddr;
2241                 iph->version = 0;
2242                 err = ipmr_cache_unresolved(mrt, vif, skb2);
2243                 read_unlock(&mrt_lock);
2244                 rcu_read_unlock();
2245                 return err;
2246         }
2247
2248         read_lock(&mrt_lock);
2249         if (!nowait && (rtm->rtm_flags & RTM_F_NOTIFY))
2250                 cache->mfc_flags |= MFC_NOTIFY;
2251         err = __ipmr_fill_mroute(mrt, skb, cache, rtm);
2252         read_unlock(&mrt_lock);
2253         rcu_read_unlock();
2254         return err;
2255 }
2256
2257 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2258                             u32 portid, u32 seq, struct mfc_cache *c, int cmd)
2259 {
2260         struct nlmsghdr *nlh;
2261         struct rtmsg *rtm;
2262         int err;
2263
2264         nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), NLM_F_MULTI);
2265         if (nlh == NULL)
2266                 return -EMSGSIZE;
2267
2268         rtm = nlmsg_data(nlh);
2269         rtm->rtm_family   = RTNL_FAMILY_IPMR;
2270         rtm->rtm_dst_len  = 32;
2271         rtm->rtm_src_len  = 32;
2272         rtm->rtm_tos      = 0;
2273         rtm->rtm_table    = mrt->id;
2274         if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2275                 goto nla_put_failure;
2276         rtm->rtm_type     = RTN_MULTICAST;
2277         rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2278         if (c->mfc_flags & MFC_STATIC)
2279                 rtm->rtm_protocol = RTPROT_STATIC;
2280         else
2281                 rtm->rtm_protocol = RTPROT_MROUTED;
2282         rtm->rtm_flags    = 0;
2283
2284         if (nla_put_be32(skb, RTA_SRC, c->mfc_origin) ||
2285             nla_put_be32(skb, RTA_DST, c->mfc_mcastgrp))
2286                 goto nla_put_failure;
2287         err = __ipmr_fill_mroute(mrt, skb, c, rtm);
2288         /* do not break the dump if cache is unresolved */
2289         if (err < 0 && err != -ENOENT)
2290                 goto nla_put_failure;
2291
2292         return nlmsg_end(skb, nlh);
2293
2294 nla_put_failure:
2295         nlmsg_cancel(skb, nlh);
2296         return -EMSGSIZE;
2297 }
2298
2299 static size_t mroute_msgsize(bool unresolved, int maxvif)
2300 {
2301         size_t len =
2302                 NLMSG_ALIGN(sizeof(struct rtmsg))
2303                 + nla_total_size(4)     /* RTA_TABLE */
2304                 + nla_total_size(4)     /* RTA_SRC */
2305                 + nla_total_size(4)     /* RTA_DST */
2306                 ;
2307
2308         if (!unresolved)
2309                 len = len
2310                       + nla_total_size(4)       /* RTA_IIF */
2311                       + nla_total_size(0)       /* RTA_MULTIPATH */
2312                       + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2313                                                 /* RTA_MFC_STATS */
2314                       + nla_total_size(sizeof(struct rta_mfc_stats))
2315                 ;
2316
2317         return len;
2318 }
2319
2320 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2321                                  int cmd)
2322 {
2323         struct net *net = read_pnet(&mrt->net);
2324         struct sk_buff *skb;
2325         int err = -ENOBUFS;
2326
2327         skb = nlmsg_new(mroute_msgsize(mfc->mfc_parent >= MAXVIFS, mrt->maxvif),
2328                         GFP_ATOMIC);
2329         if (skb == NULL)
2330                 goto errout;
2331
2332         err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd);
2333         if (err < 0)
2334                 goto errout;
2335
2336         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2337         return;
2338
2339 errout:
2340         kfree_skb(skb);
2341         if (err < 0)
2342                 rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
2343 }
2344
2345 static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2346 {
2347         struct net *net = sock_net(skb->sk);
2348         struct mr_table *mrt;
2349         struct mfc_cache *mfc;
2350         unsigned int t = 0, s_t;
2351         unsigned int h = 0, s_h;
2352         unsigned int e = 0, s_e;
2353
2354         s_t = cb->args[0];
2355         s_h = cb->args[1];
2356         s_e = cb->args[2];
2357
2358         rcu_read_lock();
2359         ipmr_for_each_table(mrt, net) {
2360                 if (t < s_t)
2361                         goto next_table;
2362                 if (t > s_t)
2363                         s_h = 0;
2364                 for (h = s_h; h < MFC_LINES; h++) {
2365                         list_for_each_entry_rcu(mfc, &mrt->mfc_cache_array[h], list) {
2366                                 if (e < s_e)
2367                                         goto next_entry;
2368                                 if (ipmr_fill_mroute(mrt, skb,
2369                                                      NETLINK_CB(cb->skb).portid,
2370                                                      cb->nlh->nlmsg_seq,
2371                                                      mfc, RTM_NEWROUTE) < 0)
2372                                         goto done;
2373 next_entry:
2374                                 e++;
2375                         }
2376                         e = s_e = 0;
2377                 }
2378                 spin_lock_bh(&mfc_unres_lock);
2379                 list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) {
2380                         if (e < s_e)
2381                                 goto next_entry2;
2382                         if (ipmr_fill_mroute(mrt, skb,
2383                                              NETLINK_CB(cb->skb).portid,
2384                                              cb->nlh->nlmsg_seq,
2385                                              mfc, RTM_NEWROUTE) < 0) {
2386                                 spin_unlock_bh(&mfc_unres_lock);
2387                                 goto done;
2388                         }
2389 next_entry2:
2390                         e++;
2391                 }
2392                 spin_unlock_bh(&mfc_unres_lock);
2393                 e = s_e = 0;
2394                 s_h = 0;
2395 next_table:
2396                 t++;
2397         }
2398 done:
2399         rcu_read_unlock();
2400
2401         cb->args[2] = e;
2402         cb->args[1] = h;
2403         cb->args[0] = t;
2404
2405         return skb->len;
2406 }
2407
2408 #ifdef CONFIG_PROC_FS
2409 /*
2410  *      The /proc interfaces to multicast routing :
2411  *      /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2412  */
2413 struct ipmr_vif_iter {
2414         struct seq_net_private p;
2415         struct mr_table *mrt;
2416         int ct;
2417 };
2418
2419 static struct vif_device *ipmr_vif_seq_idx(struct net *net,
2420                                            struct ipmr_vif_iter *iter,
2421                                            loff_t pos)
2422 {
2423         struct mr_table *mrt = iter->mrt;
2424
2425         for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
2426                 if (!VIF_EXISTS(mrt, iter->ct))
2427                         continue;
2428                 if (pos-- == 0)
2429                         return &mrt->vif_table[iter->ct];
2430         }
2431         return NULL;
2432 }
2433
2434 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2435         __acquires(mrt_lock)
2436 {
2437         struct ipmr_vif_iter *iter = seq->private;
2438         struct net *net = seq_file_net(seq);
2439         struct mr_table *mrt;
2440
2441         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2442         if (mrt == NULL)
2443                 return ERR_PTR(-ENOENT);
2444
2445         iter->mrt = mrt;
2446
2447         read_lock(&mrt_lock);
2448         return *pos ? ipmr_vif_seq_idx(net, seq->private, *pos - 1)
2449                 : SEQ_START_TOKEN;
2450 }
2451
2452 static void *ipmr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2453 {
2454         struct ipmr_vif_iter *iter = seq->private;
2455         struct net *net = seq_file_net(seq);
2456         struct mr_table *mrt = iter->mrt;
2457
2458         ++*pos;
2459         if (v == SEQ_START_TOKEN)
2460                 return ipmr_vif_seq_idx(net, iter, 0);
2461
2462         while (++iter->ct < mrt->maxvif) {
2463                 if (!VIF_EXISTS(mrt, iter->ct))
2464                         continue;
2465                 return &mrt->vif_table[iter->ct];
2466         }
2467         return NULL;
2468 }
2469
2470 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2471         __releases(mrt_lock)
2472 {
2473         read_unlock(&mrt_lock);
2474 }
2475
2476 static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2477 {
2478         struct ipmr_vif_iter *iter = seq->private;
2479         struct mr_table *mrt = iter->mrt;
2480
2481         if (v == SEQ_START_TOKEN) {
2482                 seq_puts(seq,
2483                          "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
2484         } else {
2485                 const struct vif_device *vif = v;
2486                 const char *name =  vif->dev ? vif->dev->name : "none";
2487
2488                 seq_printf(seq,
2489                            "%2Zd %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
2490                            vif - mrt->vif_table,
2491                            name, vif->bytes_in, vif->pkt_in,
2492                            vif->bytes_out, vif->pkt_out,
2493                            vif->flags, vif->local, vif->remote);
2494         }
2495         return 0;
2496 }
2497
2498 static const struct seq_operations ipmr_vif_seq_ops = {
2499         .start = ipmr_vif_seq_start,
2500         .next  = ipmr_vif_seq_next,
2501         .stop  = ipmr_vif_seq_stop,
2502         .show  = ipmr_vif_seq_show,
2503 };
2504
2505 static int ipmr_vif_open(struct inode *inode, struct file *file)
2506 {
2507         return seq_open_net(inode, file, &ipmr_vif_seq_ops,
2508                             sizeof(struct ipmr_vif_iter));
2509 }
2510
2511 static const struct file_operations ipmr_vif_fops = {
2512         .owner   = THIS_MODULE,
2513         .open    = ipmr_vif_open,
2514         .read    = seq_read,
2515         .llseek  = seq_lseek,
2516         .release = seq_release_net,
2517 };
2518
2519 struct ipmr_mfc_iter {
2520         struct seq_net_private p;
2521         struct mr_table *mrt;
2522         struct list_head *cache;
2523         int ct;
2524 };
2525
2526
2527 static struct mfc_cache *ipmr_mfc_seq_idx(struct net *net,
2528                                           struct ipmr_mfc_iter *it, loff_t pos)
2529 {
2530         struct mr_table *mrt = it->mrt;
2531         struct mfc_cache *mfc;
2532
2533         rcu_read_lock();
2534         for (it->ct = 0; it->ct < MFC_LINES; it->ct++) {
2535                 it->cache = &mrt->mfc_cache_array[it->ct];
2536                 list_for_each_entry_rcu(mfc, it->cache, list)
2537                         if (pos-- == 0)
2538                                 return mfc;
2539         }
2540         rcu_read_unlock();
2541
2542         spin_lock_bh(&mfc_unres_lock);
2543         it->cache = &mrt->mfc_unres_queue;
2544         list_for_each_entry(mfc, it->cache, list)
2545                 if (pos-- == 0)
2546                         return mfc;
2547         spin_unlock_bh(&mfc_unres_lock);
2548
2549         it->cache = NULL;
2550         return NULL;
2551 }
2552
2553
2554 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2555 {
2556         struct ipmr_mfc_iter *it = seq->private;
2557         struct net *net = seq_file_net(seq);
2558         struct mr_table *mrt;
2559
2560         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2561         if (mrt == NULL)
2562                 return ERR_PTR(-ENOENT);
2563
2564         it->mrt = mrt;
2565         it->cache = NULL;
2566         it->ct = 0;
2567         return *pos ? ipmr_mfc_seq_idx(net, seq->private, *pos - 1)
2568                 : SEQ_START_TOKEN;
2569 }
2570
2571 static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2572 {
2573         struct mfc_cache *mfc = v;
2574         struct ipmr_mfc_iter *it = seq->private;
2575         struct net *net = seq_file_net(seq);
2576         struct mr_table *mrt = it->mrt;
2577
2578         ++*pos;
2579
2580         if (v == SEQ_START_TOKEN)
2581                 return ipmr_mfc_seq_idx(net, seq->private, 0);
2582
2583         if (mfc->list.next != it->cache)
2584                 return list_entry(mfc->list.next, struct mfc_cache, list);
2585
2586         if (it->cache == &mrt->mfc_unres_queue)
2587                 goto end_of_list;
2588
2589         BUG_ON(it->cache != &mrt->mfc_cache_array[it->ct]);
2590
2591         while (++it->ct < MFC_LINES) {
2592                 it->cache = &mrt->mfc_cache_array[it->ct];
2593                 if (list_empty(it->cache))
2594                         continue;
2595                 return list_first_entry(it->cache, struct mfc_cache, list);
2596         }
2597
2598         /* exhausted cache_array, show unresolved */
2599         rcu_read_unlock();
2600         it->cache = &mrt->mfc_unres_queue;
2601         it->ct = 0;
2602
2603         spin_lock_bh(&mfc_unres_lock);
2604         if (!list_empty(it->cache))
2605                 return list_first_entry(it->cache, struct mfc_cache, list);
2606
2607 end_of_list:
2608         spin_unlock_bh(&mfc_unres_lock);
2609         it->cache = NULL;
2610
2611         return NULL;
2612 }
2613
2614 static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
2615 {
2616         struct ipmr_mfc_iter *it = seq->private;
2617         struct mr_table *mrt = it->mrt;
2618
2619         if (it->cache == &mrt->mfc_unres_queue)
2620                 spin_unlock_bh(&mfc_unres_lock);
2621         else if (it->cache == &mrt->mfc_cache_array[it->ct])
2622                 rcu_read_unlock();
2623 }
2624
2625 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2626 {
2627         int n;
2628
2629         if (v == SEQ_START_TOKEN) {
2630                 seq_puts(seq,
2631                  "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
2632         } else {
2633                 const struct mfc_cache *mfc = v;
2634                 const struct ipmr_mfc_iter *it = seq->private;
2635                 const struct mr_table *mrt = it->mrt;
2636
2637                 seq_printf(seq, "%08X %08X %-3hd",
2638                            (__force u32) mfc->mfc_mcastgrp,
2639                            (__force u32) mfc->mfc_origin,
2640                            mfc->mfc_parent);
2641
2642                 if (it->cache != &mrt->mfc_unres_queue) {
2643                         seq_printf(seq, " %8lu %8lu %8lu",
2644                                    mfc->mfc_un.res.pkt,
2645                                    mfc->mfc_un.res.bytes,
2646                                    mfc->mfc_un.res.wrong_if);
2647                         for (n = mfc->mfc_un.res.minvif;
2648                              n < mfc->mfc_un.res.maxvif; n++) {
2649                                 if (VIF_EXISTS(mrt, n) &&
2650                                     mfc->mfc_un.res.ttls[n] < 255)
2651                                         seq_printf(seq,
2652                                            " %2d:%-3d",
2653                                            n, mfc->mfc_un.res.ttls[n]);
2654                         }
2655                 } else {
2656                         /* unresolved mfc_caches don't contain
2657                          * pkt, bytes and wrong_if values
2658                          */
2659                         seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
2660                 }
2661                 seq_putc(seq, '\n');
2662         }
2663         return 0;
2664 }
2665
2666 static const struct seq_operations ipmr_mfc_seq_ops = {
2667         .start = ipmr_mfc_seq_start,
2668         .next  = ipmr_mfc_seq_next,
2669         .stop  = ipmr_mfc_seq_stop,
2670         .show  = ipmr_mfc_seq_show,
2671 };
2672
2673 static int ipmr_mfc_open(struct inode *inode, struct file *file)
2674 {
2675         return seq_open_net(inode, file, &ipmr_mfc_seq_ops,
2676                             sizeof(struct ipmr_mfc_iter));
2677 }
2678
2679 static const struct file_operations ipmr_mfc_fops = {
2680         .owner   = THIS_MODULE,
2681         .open    = ipmr_mfc_open,
2682         .read    = seq_read,
2683         .llseek  = seq_lseek,
2684         .release = seq_release_net,
2685 };
2686 #endif
2687
2688 #ifdef CONFIG_IP_PIMSM_V2
2689 static const struct net_protocol pim_protocol = {
2690         .handler        =       pim_rcv,
2691         .netns_ok       =       1,
2692 };
2693 #endif
2694
2695
2696 /*
2697  *      Setup for IP multicast routing
2698  */
2699 static int __net_init ipmr_net_init(struct net *net)
2700 {
2701         int err;
2702
2703         err = ipmr_rules_init(net);
2704         if (err < 0)
2705                 goto fail;
2706
2707 #ifdef CONFIG_PROC_FS
2708         err = -ENOMEM;
2709         if (!proc_create("ip_mr_vif", 0, net->proc_net, &ipmr_vif_fops))
2710                 goto proc_vif_fail;
2711         if (!proc_create("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_fops))
2712                 goto proc_cache_fail;
2713 #endif
2714         return 0;
2715
2716 #ifdef CONFIG_PROC_FS
2717 proc_cache_fail:
2718         remove_proc_entry("ip_mr_vif", net->proc_net);
2719 proc_vif_fail:
2720         ipmr_rules_exit(net);
2721 #endif
2722 fail:
2723         return err;
2724 }
2725
2726 static void __net_exit ipmr_net_exit(struct net *net)
2727 {
2728 #ifdef CONFIG_PROC_FS
2729         remove_proc_entry("ip_mr_cache", net->proc_net);
2730         remove_proc_entry("ip_mr_vif", net->proc_net);
2731 #endif
2732         ipmr_rules_exit(net);
2733 }
2734
2735 static struct pernet_operations ipmr_net_ops = {
2736         .init = ipmr_net_init,
2737         .exit = ipmr_net_exit,
2738 };
2739
2740 int __init ip_mr_init(void)
2741 {
2742         int err;
2743
2744         mrt_cachep = kmem_cache_create("ip_mrt_cache",
2745                                        sizeof(struct mfc_cache),
2746                                        0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
2747                                        NULL);
2748         if (!mrt_cachep)
2749                 return -ENOMEM;
2750
2751         err = register_pernet_subsys(&ipmr_net_ops);
2752         if (err)
2753                 goto reg_pernet_fail;
2754
2755         err = register_netdevice_notifier(&ip_mr_notifier);
2756         if (err)
2757                 goto reg_notif_fail;
2758 #ifdef CONFIG_IP_PIMSM_V2
2759         if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
2760                 pr_err("%s: can't add PIM protocol\n", __func__);
2761                 err = -EAGAIN;
2762                 goto add_proto_fail;
2763         }
2764 #endif
2765         rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
2766                       NULL, ipmr_rtm_dumproute, NULL);
2767         return 0;
2768
2769 #ifdef CONFIG_IP_PIMSM_V2
2770 add_proto_fail:
2771         unregister_netdevice_notifier(&ip_mr_notifier);
2772 #endif
2773 reg_notif_fail:
2774         unregister_pernet_subsys(&ipmr_net_ops);
2775 reg_pernet_fail:
2776         kmem_cache_destroy(mrt_cachep);
2777         return err;
2778 }