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         possible_net_t          net;
  77         u32                     id;
  78         struct sock __rcu       *mroute_sk;
  79         struct timer_list       ipmr_expire_timer;
  80         struct list_head        mfc_unres_queue;
  81         struct list_head        mfc_cache_array[MFC_LINES];
  82         struct vif_device       vif_table[MAXVIFS];
  83         int                     maxvif;
  84         atomic_t                cache_resolve_queue_len;
  85         bool                    mroute_do_assert;
  86         bool                    mroute_do_pim;
  87 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
  88         int                     mroute_reg_vif_num;
  89 #endif
  90 };
  91
  92 struct ipmr_rule {
  93         struct fib_rule         common;
  94 };
  95
  96 struct ipmr_result {
  97         struct mr_table         *mrt;
  98 };
  99
 100 /* Big lock, protecting vif table, mrt cache and mroute socket state.
 101  * Note that the changes are semaphored via rtnl_lock.
 102  */
 103
 104 static DEFINE_RWLOCK(mrt_lock);
 105
 106 /*
 107  *      Multicast router control variables
 108  */
 109
 110 #define VIF_EXISTS(_mrt, _idx) ((_mrt)->vif_table[_idx].dev != NULL)
 111
 112 /* Special spinlock for queue of unresolved entries */
 113 static DEFINE_SPINLOCK(mfc_unres_lock);
 114
 115 /* We return to original Alan's scheme. Hash table of resolved
 116  * entries is changed only in process context and protected
 117  * with weak lock mrt_lock. Queue of unresolved entries is protected
 118  * with strong spinlock mfc_unres_lock.
 119  *
 120  * In this case data path is free of exclusive locks at all.
 121  */
 122
 123 static struct kmem_cache *mrt_cachep __read_mostly;
 124
 125 static struct mr_table *ipmr_new_table(struct net *net, u32 id);
 126 static void ipmr_free_table(struct mr_table *mrt);
 127
 128 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
 129                           struct sk_buff *skb, struct mfc_cache *cache,
 130                           int local);
 131 static int ipmr_cache_report(struct mr_table *mrt,
 132                              struct sk_buff *pkt, vifi_t vifi, int assert);
 133 static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
 134                               struct mfc_cache *c, struct rtmsg *rtm);
 135 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
 136                                  int cmd);
 137 static void mroute_clean_tables(struct mr_table *mrt);
 138 static void ipmr_expire_process(unsigned long arg);
 139
 140 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 141 #define ipmr_for_each_table(mrt, net) \
 142         list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list)
 143
 144 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 145 {
 146         struct mr_table *mrt;
 147
 148         ipmr_for_each_table(mrt, net) {
 149                 if (mrt->id == id)
 150                         return mrt;
 151         }
 152         return NULL;
 153 }
 154
 155 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 156                            struct mr_table **mrt)
 157 {
 158         int err;
 159         struct ipmr_result res;
 160         struct fib_lookup_arg arg = {
 161                 .result = &res,
 162                 .flags = FIB_LOOKUP_NOREF,
 163         };
 164
 165         err = fib_rules_lookup(net->ipv4.mr_rules_ops,
 166                                flowi4_to_flowi(flp4), 0, &arg);
 167         if (err < 0)
 168                 return err;
 169         *mrt = res.mrt;
 170         return 0;
 171 }
 172
 173 static int ipmr_rule_action(struct fib_rule *rule, struct flowi *flp,
 174                             int flags, struct fib_lookup_arg *arg)
 175 {
 176         struct ipmr_result *res = arg->result;
 177         struct mr_table *mrt;
 178
 179         switch (rule->action) {
 180         case FR_ACT_TO_TBL:
 181                 break;
 182         case FR_ACT_UNREACHABLE:
 183                 return -ENETUNREACH;
 184         case FR_ACT_PROHIBIT:
 185                 return -EACCES;
 186         case FR_ACT_BLACKHOLE:
 187         default:
 188                 return -EINVAL;
 189         }
 190
 191         mrt = ipmr_get_table(rule->fr_net, rule->table);
 192         if (!mrt)
 193                 return -EAGAIN;
 194         res->mrt = mrt;
 195         return 0;
 196 }
 197
 198 static int ipmr_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
 199 {
 200         return 1;
 201 }
 202
 203 static const struct nla_policy ipmr_rule_policy[FRA_MAX + 1] = {
 204         FRA_GENERIC_POLICY,
 205 };
 206
 207 static int ipmr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
 208                                struct fib_rule_hdr *frh, struct nlattr **tb)
 209 {
 210         return 0;
 211 }
 212
 213 static int ipmr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
 214                              struct nlattr **tb)
 215 {
 216         return 1;
 217 }
 218
 219 static int ipmr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
 220                           struct fib_rule_hdr *frh)
 221 {
 222         frh->dst_len = 0;
 223         frh->src_len = 0;
 224         frh->tos     = 0;
 225         return 0;
 226 }
 227
 228 static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
 229         .family         = RTNL_FAMILY_IPMR,
 230         .rule_size      = sizeof(struct ipmr_rule),
 231         .addr_size      = sizeof(u32),
 232         .action         = ipmr_rule_action,
 233         .match          = ipmr_rule_match,
 234         .configure      = ipmr_rule_configure,
 235         .compare        = ipmr_rule_compare,
 236         .fill           = ipmr_rule_fill,
 237         .nlgroup        = RTNLGRP_IPV4_RULE,
 238         .policy         = ipmr_rule_policy,
 239         .owner          = THIS_MODULE,
 240 };
 241
 242 static int __net_init ipmr_rules_init(struct net *net)
 243 {
 244         struct fib_rules_ops *ops;
 245         struct mr_table *mrt;
 246         int err;
 247
 248         ops = fib_rules_register(&ipmr_rules_ops_template, net);
 249         if (IS_ERR(ops))
 250                 return PTR_ERR(ops);
 251
 252         INIT_LIST_HEAD(&net->ipv4.mr_tables);
 253
 254         mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 255         if (!mrt) {
 256                 err = -ENOMEM;
 257                 goto err1;
 258         }
 259
 260         err = fib_default_rule_add(ops, 0x7fff, RT_TABLE_DEFAULT, 0);
 261         if (err < 0)
 262                 goto err2;
 263
 264         net->ipv4.mr_rules_ops = ops;
 265         return 0;
 266
 267 err2:
 268         ipmr_free_table(mrt);
 269 err1:
 270         fib_rules_unregister(ops);
 271         return err;
 272 }
 273
 274 static void __net_exit ipmr_rules_exit(struct net *net)
 275 {
 276         struct mr_table *mrt, *next;
 277
 278         rtnl_lock();
 279         list_for_each_entry_safe(mrt, next, &net->ipv4.mr_tables, list) {
 280                 list_del(&mrt->list);
 281                 ipmr_free_table(mrt);
 282         }
 283         fib_rules_unregister(net->ipv4.mr_rules_ops);
 284         rtnl_unlock();
 285 }
 286 #else
 287 #define ipmr_for_each_table(mrt, net) \
 288         for (mrt = net->ipv4.mrt; mrt; mrt = NULL)
 289
 290 static struct mr_table *ipmr_get_table(struct net *net, u32 id)
 291 {
 292         return net->ipv4.mrt;
 293 }
 294
 295 static int ipmr_fib_lookup(struct net *net, struct flowi4 *flp4,
 296                            struct mr_table **mrt)
 297 {
 298         *mrt = net->ipv4.mrt;
 299         return 0;
 300 }
 301
 302 static int __net_init ipmr_rules_init(struct net *net)
 303 {
 304         net->ipv4.mrt = ipmr_new_table(net, RT_TABLE_DEFAULT);
 305         return net->ipv4.mrt ? 0 : -ENOMEM;
 306 }
 307
 308 static void __net_exit ipmr_rules_exit(struct net *net)
 309 {
 310         rtnl_lock();
 311         ipmr_free_table(net->ipv4.mrt);
 312         net->ipv4.mrt = NULL;
 313         rtnl_unlock();
 314 }
 315 #endif
 316
 317 static struct mr_table *ipmr_new_table(struct net *net, u32 id)
 318 {
 319         struct mr_table *mrt;
 320         unsigned int i;
 321
 322         mrt = ipmr_get_table(net, id);
 323         if (mrt)
 324                 return mrt;
 325
 326         mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
 327         if (!mrt)
 328                 return NULL;
 329         write_pnet(&mrt->net, net);
 330         mrt->id = id;
 331
 332         /* Forwarding cache */
 333         for (i = 0; i < MFC_LINES; i++)
 334                 INIT_LIST_HEAD(&mrt->mfc_cache_array[i]);
 335
 336         INIT_LIST_HEAD(&mrt->mfc_unres_queue);
 337
 338         setup_timer(&mrt->ipmr_expire_timer, ipmr_expire_process,
 339                     (unsigned long)mrt);
 340
 341 #ifdef CONFIG_IP_PIMSM
 342         mrt->mroute_reg_vif_num = -1;
 343 #endif
 344 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 345         list_add_tail_rcu(&mrt->list, &net->ipv4.mr_tables);
 346 #endif
 347         return mrt;
 348 }
 349
 350 static void ipmr_free_table(struct mr_table *mrt)
 351 {
 352         del_timer_sync(&mrt->ipmr_expire_timer);
 353         mroute_clean_tables(mrt);
 354         kfree(mrt);
 355 }
 356
 357 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
 358
 359 static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
 360 {
 361         struct net *net = dev_net(dev);
 362
 363         dev_close(dev);
 364
 365         dev = __dev_get_by_name(net, "tunl0");
 366         if (dev) {
 367                 const struct net_device_ops *ops = dev->netdev_ops;
 368                 struct ifreq ifr;
 369                 struct ip_tunnel_parm p;
 370
 371                 memset(&p, 0, sizeof(p));
 372                 p.iph.daddr = v->vifc_rmt_addr.s_addr;
 373                 p.iph.saddr = v->vifc_lcl_addr.s_addr;
 374                 p.iph.version = 4;
 375                 p.iph.ihl = 5;
 376                 p.iph.protocol = IPPROTO_IPIP;
 377                 sprintf(p.name, "dvmrp%d", v->vifc_vifi);
 378                 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
 379
 380                 if (ops->ndo_do_ioctl) {
 381                         mm_segment_t oldfs = get_fs();
 382
 383                         set_fs(KERNEL_DS);
 384                         ops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
 385                         set_fs(oldfs);
 386                 }
 387         }
 388 }
 389
 390 static
 391 struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
 392 {
 393         struct net_device  *dev;
 394
 395         dev = __dev_get_by_name(net, "tunl0");
 396
 397         if (dev) {
 398                 const struct net_device_ops *ops = dev->netdev_ops;
 399                 int err;
 400                 struct ifreq ifr;
 401                 struct ip_tunnel_parm p;
 402                 struct in_device  *in_dev;
 403
 404                 memset(&p, 0, sizeof(p));
 405                 p.iph.daddr = v->vifc_rmt_addr.s_addr;
 406                 p.iph.saddr = v->vifc_lcl_addr.s_addr;
 407                 p.iph.version = 4;
 408                 p.iph.ihl = 5;
 409                 p.iph.protocol = IPPROTO_IPIP;
 410                 sprintf(p.name, "dvmrp%d", v->vifc_vifi);
 411                 ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
 412
 413                 if (ops->ndo_do_ioctl) {
 414                         mm_segment_t oldfs = get_fs();
 415
 416                         set_fs(KERNEL_DS);
 417                         err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
 418                         set_fs(oldfs);
 419                 } else {
 420                         err = -EOPNOTSUPP;
 421                 }
 422                 dev = NULL;
 423
 424                 if (err == 0 &&
 425                     (dev = __dev_get_by_name(net, p.name)) != NULL) {
 426                         dev->flags |= IFF_MULTICAST;
 427
 428                         in_dev = __in_dev_get_rtnl(dev);
 429                         if (!in_dev)
 430                                 goto failure;
 431
 432                         ipv4_devconf_setall(in_dev);
 433                         neigh_parms_data_state_setall(in_dev->arp_parms);
 434                         IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
 435
 436                         if (dev_open(dev))
 437                                 goto failure;
 438                         dev_hold(dev);
 439                 }
 440         }
 441         return dev;
 442
 443 failure:
 444         /* allow the register to be completed before unregistering. */
 445         rtnl_unlock();
 446         rtnl_lock();
 447
 448         unregister_netdevice(dev);
 449         return NULL;
 450 }
 451
 452 #ifdef CONFIG_IP_PIMSM
 453
 454 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
 455 {
 456         struct net *net = dev_net(dev);
 457         struct mr_table *mrt;
 458         struct flowi4 fl4 = {
 459                 .flowi4_oif     = dev->ifindex,
 460                 .flowi4_iif     = skb->skb_iif ? : LOOPBACK_IFINDEX,
 461                 .flowi4_mark    = skb->mark,
 462         };
 463         int err;
 464
 465         err = ipmr_fib_lookup(net, &fl4, &mrt);
 466         if (err < 0) {
 467                 kfree_skb(skb);
 468                 return err;
 469         }
 470
 471         read_lock(&mrt_lock);
 472         dev->stats.tx_bytes += skb->len;
 473         dev->stats.tx_packets++;
 474         ipmr_cache_report(mrt, skb, mrt->mroute_reg_vif_num, IGMPMSG_WHOLEPKT);
 475         read_unlock(&mrt_lock);
 476         kfree_skb(skb);
 477         return NETDEV_TX_OK;
 478 }
 479
 480 static int reg_vif_get_iflink(const struct net_device *dev)
 481 {
 482         return 0;
 483 }
 484
 485 static const struct net_device_ops reg_vif_netdev_ops = {
 486         .ndo_start_xmit = reg_vif_xmit,
 487         .ndo_get_iflink = reg_vif_get_iflink,
 488 };
 489
 490 static void reg_vif_setup(struct net_device *dev)
 491 {
 492         dev->type               = ARPHRD_PIMREG;
 493         dev->mtu                = ETH_DATA_LEN - sizeof(struct iphdr) - 8;
 494         dev->flags              = IFF_NOARP;
 495         dev->netdev_ops         = &reg_vif_netdev_ops;
 496         dev->destructor         = free_netdev;
 497         dev->features           |= NETIF_F_NETNS_LOCAL;
 498 }
 499
 500 static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
 501 {
 502         struct net_device *dev;
 503         struct in_device *in_dev;
 504         char name[IFNAMSIZ];
 505
 506         if (mrt->id == RT_TABLE_DEFAULT)
 507                 sprintf(name, "pimreg");
 508         else
 509                 sprintf(name, "pimreg%u", mrt->id);
 510
 511         dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
 512
 513         if (!dev)
 514                 return NULL;
 515
 516         dev_net_set(dev, net);
 517
 518         if (register_netdevice(dev)) {
 519                 free_netdev(dev);
 520                 return NULL;
 521         }
 522
 523         rcu_read_lock();
 524         in_dev = __in_dev_get_rcu(dev);
 525         if (!in_dev) {
 526                 rcu_read_unlock();
 527                 goto failure;
 528         }
 529
 530         ipv4_devconf_setall(in_dev);
 531         neigh_parms_data_state_setall(in_dev->arp_parms);
 532         IPV4_DEVCONF(in_dev->cnf, RP_FILTER) = 0;
 533         rcu_read_unlock();
 534
 535         if (dev_open(dev))
 536                 goto failure;
 537
 538         dev_hold(dev);
 539
 540         return dev;
 541
 542 failure:
 543         /* allow the register to be completed before unregistering. */
 544         rtnl_unlock();
 545         rtnl_lock();
 546
 547         unregister_netdevice(dev);
 548         return NULL;
 549 }
 550 #endif
 551
 552 /**
 553  *      vif_delete - Delete a VIF entry
 554  *      @notify: Set to 1, if the caller is a notifier_call
 555  */
 556
 557 static int vif_delete(struct mr_table *mrt, int vifi, int notify,
 558                       struct list_head *head)
 559 {
 560         struct vif_device *v;
 561         struct net_device *dev;
 562         struct in_device *in_dev;
 563
 564         if (vifi < 0 || vifi >= mrt->maxvif)
 565                 return -EADDRNOTAVAIL;
 566
 567         v = &mrt->vif_table[vifi];
 568
 569         write_lock_bh(&mrt_lock);
 570         dev = v->dev;
 571         v->dev = NULL;
 572
 573         if (!dev) {
 574                 write_unlock_bh(&mrt_lock);
 575                 return -EADDRNOTAVAIL;
 576         }
 577
 578 #ifdef CONFIG_IP_PIMSM
 579         if (vifi == mrt->mroute_reg_vif_num)
 580                 mrt->mroute_reg_vif_num = -1;
 581 #endif
 582
 583         if (vifi + 1 == mrt->maxvif) {
 584                 int tmp;
 585
 586                 for (tmp = vifi - 1; tmp >= 0; tmp--) {
 587                         if (VIF_EXISTS(mrt, tmp))
 588                                 break;
 589                 }
 590                 mrt->maxvif = tmp+1;
 591         }
 592
 593         write_unlock_bh(&mrt_lock);
 594
 595         dev_set_allmulti(dev, -1);
 596
 597         in_dev = __in_dev_get_rtnl(dev);
 598         if (in_dev) {
 599                 IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
 600                 inet_netconf_notify_devconf(dev_net(dev),
 601                                             NETCONFA_MC_FORWARDING,
 602                                             dev->ifindex, &in_dev->cnf);
 603                 ip_rt_multicast_event(in_dev);
 604         }
 605
 606         if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER) && !notify)
 607                 unregister_netdevice_queue(dev, head);
 608
 609         dev_put(dev);
 610         return 0;
 611 }
 612
 613 static void ipmr_cache_free_rcu(struct rcu_head *head)
 614 {
 615         struct mfc_cache *c = container_of(head, struct mfc_cache, rcu);
 616
 617         kmem_cache_free(mrt_cachep, c);
 618 }
 619
 620 static inline void ipmr_cache_free(struct mfc_cache *c)
 621 {
 622         call_rcu(&c->rcu, ipmr_cache_free_rcu);
 623 }
 624
 625 /* Destroy an unresolved cache entry, killing queued skbs
 626  * and reporting error to netlink readers.
 627  */
 628
 629 static void ipmr_destroy_unres(struct mr_table *mrt, struct mfc_cache *c)
 630 {
 631         struct net *net = read_pnet(&mrt->net);
 632         struct sk_buff *skb;
 633         struct nlmsgerr *e;
 634
 635         atomic_dec(&mrt->cache_resolve_queue_len);
 636
 637         while ((skb = skb_dequeue(&c->mfc_un.unres.unresolved))) {
 638                 if (ip_hdr(skb)->version == 0) {
 639                         struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
 640                         nlh->nlmsg_type = NLMSG_ERROR;
 641                         nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
 642                         skb_trim(skb, nlh->nlmsg_len);
 643                         e = nlmsg_data(nlh);
 644                         e->error = -ETIMEDOUT;
 645                         memset(&e->msg, 0, sizeof(e->msg));
 646
 647                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
 648                 } else {
 649                         kfree_skb(skb);
 650                 }
 651         }
 652
 653         ipmr_cache_free(c);
 654 }
 655
 656
 657 /* Timer process for the unresolved queue. */
 658
 659 static void ipmr_expire_process(unsigned long arg)
 660 {
 661         struct mr_table *mrt = (struct mr_table *)arg;
 662         unsigned long now;
 663         unsigned long expires;
 664         struct mfc_cache *c, *next;
 665
 666         if (!spin_trylock(&mfc_unres_lock)) {
 667                 mod_timer(&mrt->ipmr_expire_timer, jiffies+HZ/10);
 668                 return;
 669         }
 670
 671         if (list_empty(&mrt->mfc_unres_queue))
 672                 goto out;
 673
 674         now = jiffies;
 675         expires = 10*HZ;
 676
 677         list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
 678                 if (time_after(c->mfc_un.unres.expires, now)) {
 679                         unsigned long interval = c->mfc_un.unres.expires - now;
 680                         if (interval < expires)
 681                                 expires = interval;
 682                         continue;
 683                 }
 684
 685                 list_del(&c->list);
 686                 mroute_netlink_event(mrt, c, RTM_DELROUTE);
 687                 ipmr_destroy_unres(mrt, c);
 688         }
 689
 690         if (!list_empty(&mrt->mfc_unres_queue))
 691                 mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
 692
 693 out:
 694         spin_unlock(&mfc_unres_lock);
 695 }
 696
 697 /* Fill oifs list. It is called under write locked mrt_lock. */
 698
 699 static void ipmr_update_thresholds(struct mr_table *mrt, struct mfc_cache *cache,
 700                                    unsigned char *ttls)
 701 {
 702         int vifi;
 703
 704         cache->mfc_un.res.minvif = MAXVIFS;
 705         cache->mfc_un.res.maxvif = 0;
 706         memset(cache->mfc_un.res.ttls, 255, MAXVIFS);
 707
 708         for (vifi = 0; vifi < mrt->maxvif; vifi++) {
 709                 if (VIF_EXISTS(mrt, vifi) &&
 710                     ttls[vifi] && ttls[vifi] < 255) {
 711                         cache->mfc_un.res.ttls[vifi] = ttls[vifi];
 712                         if (cache->mfc_un.res.minvif > vifi)
 713                                 cache->mfc_un.res.minvif = vifi;
 714                         if (cache->mfc_un.res.maxvif <= vifi)
 715                                 cache->mfc_un.res.maxvif = vifi + 1;
 716                 }
 717         }
 718 }
 719
 720 static int vif_add(struct net *net, struct mr_table *mrt,
 721                    struct vifctl *vifc, int mrtsock)
 722 {
 723         int vifi = vifc->vifc_vifi;
 724         struct vif_device *v = &mrt->vif_table[vifi];
 725         struct net_device *dev;
 726         struct in_device *in_dev;
 727         int err;
 728
 729         /* Is vif busy ? */
 730         if (VIF_EXISTS(mrt, vifi))
 731                 return -EADDRINUSE;
 732
 733         switch (vifc->vifc_flags) {
 734 #ifdef CONFIG_IP_PIMSM
 735         case VIFF_REGISTER:
 736                 /*
 737                  * Special Purpose VIF in PIM
 738                  * All the packets will be sent to the daemon
 739                  */
 740                 if (mrt->mroute_reg_vif_num >= 0)
 741                         return -EADDRINUSE;
 742                 dev = ipmr_reg_vif(net, mrt);
 743                 if (!dev)
 744                         return -ENOBUFS;
 745                 err = dev_set_allmulti(dev, 1);
 746                 if (err) {
 747                         unregister_netdevice(dev);
 748                         dev_put(dev);
 749                         return err;
 750                 }
 751                 break;
 752 #endif
 753         case VIFF_TUNNEL:
 754                 dev = ipmr_new_tunnel(net, vifc);
 755                 if (!dev)
 756                         return -ENOBUFS;
 757                 err = dev_set_allmulti(dev, 1);
 758                 if (err) {
 759                         ipmr_del_tunnel(dev, vifc);
 760                         dev_put(dev);
 761                         return err;
 762                 }
 763                 break;
 764
 765         case VIFF_USE_IFINDEX:
 766         case 0:
 767                 if (vifc->vifc_flags == VIFF_USE_IFINDEX) {
 768                         dev = dev_get_by_index(net, vifc->vifc_lcl_ifindex);
 769                         if (dev && !__in_dev_get_rtnl(dev)) {
 770                                 dev_put(dev);
 771                                 return -EADDRNOTAVAIL;
 772                         }
 773                 } else {
 774                         dev = ip_dev_find(net, vifc->vifc_lcl_addr.s_addr);
 775                 }
 776                 if (!dev)
 777                         return -EADDRNOTAVAIL;
 778                 err = dev_set_allmulti(dev, 1);
 779                 if (err) {
 780                         dev_put(dev);
 781                         return err;
 782                 }
 783                 break;
 784         default:
 785                 return -EINVAL;
 786         }
 787
 788         in_dev = __in_dev_get_rtnl(dev);
 789         if (!in_dev) {
 790                 dev_put(dev);
 791                 return -EADDRNOTAVAIL;
 792         }
 793         IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
 794         inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING, dev->ifindex,
 795                                     &in_dev->cnf);
 796         ip_rt_multicast_event(in_dev);
 797
 798         /* Fill in the VIF structures */
 799
 800         v->rate_limit = vifc->vifc_rate_limit;
 801         v->local = vifc->vifc_lcl_addr.s_addr;
 802         v->remote = vifc->vifc_rmt_addr.s_addr;
 803         v->flags = vifc->vifc_flags;
 804         if (!mrtsock)
 805                 v->flags |= VIFF_STATIC;
 806         v->threshold = vifc->vifc_threshold;
 807         v->bytes_in = 0;
 808         v->bytes_out = 0;
 809         v->pkt_in = 0;
 810         v->pkt_out = 0;
 811         v->link = dev->ifindex;
 812         if (v->flags & (VIFF_TUNNEL | VIFF_REGISTER))
 813                 v->link = dev_get_iflink(dev);
 814
 815         /* And finish update writing critical data */
 816         write_lock_bh(&mrt_lock);
 817         v->dev = dev;
 818 #ifdef CONFIG_IP_PIMSM
 819         if (v->flags & VIFF_REGISTER)
 820                 mrt->mroute_reg_vif_num = vifi;
 821 #endif
 822         if (vifi+1 > mrt->maxvif)
 823                 mrt->maxvif = vifi+1;
 824         write_unlock_bh(&mrt_lock);
 825         return 0;
 826 }
 827
 828 /* called with rcu_read_lock() */
 829 static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt,
 830                                          __be32 origin,
 831                                          __be32 mcastgrp)
 832 {
 833         int line = MFC_HASH(mcastgrp, origin);
 834         struct mfc_cache *c;
 835
 836         list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list) {
 837                 if (c->mfc_origin == origin && c->mfc_mcastgrp == mcastgrp)
 838                         return c;
 839         }
 840         return NULL;
 841 }
 842
 843 /* Look for a (*,*,oif) entry */
 844 static struct mfc_cache *ipmr_cache_find_any_parent(struct mr_table *mrt,
 845                                                     int vifi)
 846 {
 847         int line = MFC_HASH(htonl(INADDR_ANY), htonl(INADDR_ANY));
 848         struct mfc_cache *c;
 849
 850         list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list)
 851                 if (c->mfc_origin == htonl(INADDR_ANY) &&
 852                     c->mfc_mcastgrp == htonl(INADDR_ANY) &&
 853                     c->mfc_un.res.ttls[vifi] < 255)
 854                         return c;
 855
 856         return NULL;
 857 }
 858
 859 /* Look for a (*,G) entry */
 860 static struct mfc_cache *ipmr_cache_find_any(struct mr_table *mrt,
 861                                              __be32 mcastgrp, int vifi)
 862 {
 863         int line = MFC_HASH(mcastgrp, htonl(INADDR_ANY));
 864         struct mfc_cache *c, *proxy;
 865
 866         if (mcastgrp == htonl(INADDR_ANY))
 867                 goto skip;
 868
 869         list_for_each_entry_rcu(c, &mrt->mfc_cache_array[line], list)
 870                 if (c->mfc_origin == htonl(INADDR_ANY) &&
 871                     c->mfc_mcastgrp == mcastgrp) {
 872                         if (c->mfc_un.res.ttls[vifi] < 255)
 873                                 return c;
 874
 875                         /* It's ok if the vifi is part of the static tree */
 876                         proxy = ipmr_cache_find_any_parent(mrt,
 877                                                            c->mfc_parent);
 878                         if (proxy && proxy->mfc_un.res.ttls[vifi] < 255)
 879                                 return c;
 880                 }
 881
 882 skip:
 883         return ipmr_cache_find_any_parent(mrt, vifi);
 884 }
 885
 886 /*
 887  *      Allocate a multicast cache entry
 888  */
 889 static struct mfc_cache *ipmr_cache_alloc(void)
 890 {
 891         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
 892
 893         if (c)
 894                 c->mfc_un.res.minvif = MAXVIFS;
 895         return c;
 896 }
 897
 898 static struct mfc_cache *ipmr_cache_alloc_unres(void)
 899 {
 900         struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
 901
 902         if (c) {
 903                 skb_queue_head_init(&c->mfc_un.unres.unresolved);
 904                 c->mfc_un.unres.expires = jiffies + 10*HZ;
 905         }
 906         return c;
 907 }
 908
 909 /*
 910  *      A cache entry has gone into a resolved state from queued
 911  */
 912
 913 static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
 914                                struct mfc_cache *uc, struct mfc_cache *c)
 915 {
 916         struct sk_buff *skb;
 917         struct nlmsgerr *e;
 918
 919         /* Play the pending entries through our router */
 920
 921         while ((skb = __skb_dequeue(&uc->mfc_un.unres.unresolved))) {
 922                 if (ip_hdr(skb)->version == 0) {
 923                         struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
 924
 925                         if (__ipmr_fill_mroute(mrt, skb, c, nlmsg_data(nlh)) > 0) {
 926                                 nlh->nlmsg_len = skb_tail_pointer(skb) -
 927                                                  (u8 *)nlh;
 928                         } else {
 929                                 nlh->nlmsg_type = NLMSG_ERROR;
 930                                 nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
 931                                 skb_trim(skb, nlh->nlmsg_len);
 932                                 e = nlmsg_data(nlh);
 933                                 e->error = -EMSGSIZE;
 934                                 memset(&e->msg, 0, sizeof(e->msg));
 935                         }
 936
 937                         rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
 938                 } else {
 939                         ip_mr_forward(net, mrt, skb, c, 0);
 940                 }
 941         }
 942 }
 943
 944 /*
 945  *      Bounce a cache query up to mrouted. We could use netlink for this but mrouted
 946  *      expects the following bizarre scheme.
 947  *
 948  *      Called under mrt_lock.
 949  */
 950
 951 static int ipmr_cache_report(struct mr_table *mrt,
 952                              struct sk_buff *pkt, vifi_t vifi, int assert)
 953 {
 954         struct sk_buff *skb;
 955         const int ihl = ip_hdrlen(pkt);
 956         struct igmphdr *igmp;
 957         struct igmpmsg *msg;
 958         struct sock *mroute_sk;
 959         int ret;
 960
 961 #ifdef CONFIG_IP_PIMSM
 962         if (assert == IGMPMSG_WHOLEPKT)
 963                 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
 964         else
 965 #endif
 966                 skb = alloc_skb(128, GFP_ATOMIC);
 967
 968         if (!skb)
 969                 return -ENOBUFS;
 970
 971 #ifdef CONFIG_IP_PIMSM
 972         if (assert == IGMPMSG_WHOLEPKT) {
 973                 /* Ugly, but we have no choice with this interface.
 974                  * Duplicate old header, fix ihl, length etc.
 975                  * And all this only to mangle msg->im_msgtype and
 976                  * to set msg->im_mbz to "mbz" :-)
 977                  */
 978                 skb_push(skb, sizeof(struct iphdr));
 979                 skb_reset_network_header(skb);
 980                 skb_reset_transport_header(skb);
 981                 msg = (struct igmpmsg *)skb_network_header(skb);
 982                 memcpy(msg, skb_network_header(pkt), sizeof(struct iphdr));
 983                 msg->im_msgtype = IGMPMSG_WHOLEPKT;
 984                 msg->im_mbz = 0;
 985                 msg->im_vif = mrt->mroute_reg_vif_num;
 986                 ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
 987                 ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
 988                                              sizeof(struct iphdr));
 989         } else
 990 #endif
 991         {
 992
 993         /* Copy the IP header */
 994
 995         skb_set_network_header(skb, skb->len);
 996         skb_put(skb, ihl);
 997         skb_copy_to_linear_data(skb, pkt->data, ihl);
 998         ip_hdr(skb)->protocol = 0;      /* Flag to the kernel this is a route add */
 999         msg = (struct igmpmsg *)skb_network_header(skb);
1000         msg->im_vif = vifi;
1001         skb_dst_set(skb, dst_clone(skb_dst(pkt)));
1002
1003         /* Add our header */
1004
1005         igmp = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
1006         igmp->type      =
1007         msg->im_msgtype = assert;
1008         igmp->code      = 0;
1009         ip_hdr(skb)->tot_len = htons(skb->len);         /* Fix the length */
1010         skb->transport_header = skb->network_header;
1011         }
1012
1013         rcu_read_lock();
1014         mroute_sk = rcu_dereference(mrt->mroute_sk);
1015         if (!mroute_sk) {
1016                 rcu_read_unlock();
1017                 kfree_skb(skb);
1018                 return -EINVAL;
1019         }
1020
1021         /* Deliver to mrouted */
1022
1023         ret = sock_queue_rcv_skb(mroute_sk, skb);
1024         rcu_read_unlock();
1025         if (ret < 0) {
1026                 net_warn_ratelimited("mroute: pending queue full, dropping entries\n");
1027                 kfree_skb(skb);
1028         }
1029
1030         return ret;
1031 }
1032
1033 /*
1034  *      Queue a packet for resolution. It gets locked cache entry!
1035  */
1036
1037 static int
1038 ipmr_cache_unresolved(struct mr_table *mrt, vifi_t vifi, struct sk_buff *skb)
1039 {
1040         bool found = false;
1041         int err;
1042         struct mfc_cache *c;
1043         const struct iphdr *iph = ip_hdr(skb);
1044
1045         spin_lock_bh(&mfc_unres_lock);
1046         list_for_each_entry(c, &mrt->mfc_unres_queue, list) {
1047                 if (c->mfc_mcastgrp == iph->daddr &&
1048                     c->mfc_origin == iph->saddr) {
1049                         found = true;
1050                         break;
1051                 }
1052         }
1053
1054         if (!found) {
1055                 /* Create a new entry if allowable */
1056
1057                 if (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
1058                     (c = ipmr_cache_alloc_unres()) == NULL) {
1059                         spin_unlock_bh(&mfc_unres_lock);
1060
1061                         kfree_skb(skb);
1062                         return -ENOBUFS;
1063                 }
1064
1065                 /* Fill in the new cache entry */
1066
1067                 c->mfc_parent   = -1;
1068                 c->mfc_origin   = iph->saddr;
1069                 c->mfc_mcastgrp = iph->daddr;
1070
1071                 /* Reflect first query at mrouted. */
1072
1073                 err = ipmr_cache_report(mrt, skb, vifi, IGMPMSG_NOCACHE);
1074                 if (err < 0) {
1075                         /* If the report failed throw the cache entry
1076                            out - Brad Parker
1077                          */
1078                         spin_unlock_bh(&mfc_unres_lock);
1079
1080                         ipmr_cache_free(c);
1081                         kfree_skb(skb);
1082                         return err;
1083                 }
1084
1085                 atomic_inc(&mrt->cache_resolve_queue_len);
1086                 list_add(&c->list, &mrt->mfc_unres_queue);
1087                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1088
1089                 if (atomic_read(&mrt->cache_resolve_queue_len) == 1)
1090                         mod_timer(&mrt->ipmr_expire_timer, c->mfc_un.unres.expires);
1091         }
1092
1093         /* See if we can append the packet */
1094
1095         if (c->mfc_un.unres.unresolved.qlen > 3) {
1096                 kfree_skb(skb);
1097                 err = -ENOBUFS;
1098         } else {
1099                 skb_queue_tail(&c->mfc_un.unres.unresolved, skb);
1100                 err = 0;
1101         }
1102
1103         spin_unlock_bh(&mfc_unres_lock);
1104         return err;
1105 }
1106
1107 /*
1108  *      MFC cache manipulation by user space mroute daemon
1109  */
1110
1111 static int ipmr_mfc_delete(struct mr_table *mrt, struct mfcctl *mfc, int parent)
1112 {
1113         int line;
1114         struct mfc_cache *c, *next;
1115
1116         line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1117
1118         list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[line], list) {
1119                 if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1120                     c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr &&
1121                     (parent == -1 || parent == c->mfc_parent)) {
1122                         list_del_rcu(&c->list);
1123                         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1124                         ipmr_cache_free(c);
1125                         return 0;
1126                 }
1127         }
1128         return -ENOENT;
1129 }
1130
1131 static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
1132                         struct mfcctl *mfc, int mrtsock, int parent)
1133 {
1134         bool found = false;
1135         int line;
1136         struct mfc_cache *uc, *c;
1137
1138         if (mfc->mfcc_parent >= MAXVIFS)
1139                 return -ENFILE;
1140
1141         line = MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr);
1142
1143         list_for_each_entry(c, &mrt->mfc_cache_array[line], list) {
1144                 if (c->mfc_origin == mfc->mfcc_origin.s_addr &&
1145                     c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr &&
1146                     (parent == -1 || parent == c->mfc_parent)) {
1147                         found = true;
1148                         break;
1149                 }
1150         }
1151
1152         if (found) {
1153                 write_lock_bh(&mrt_lock);
1154                 c->mfc_parent = mfc->mfcc_parent;
1155                 ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1156                 if (!mrtsock)
1157                         c->mfc_flags |= MFC_STATIC;
1158                 write_unlock_bh(&mrt_lock);
1159                 mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1160                 return 0;
1161         }
1162
1163         if (mfc->mfcc_mcastgrp.s_addr != htonl(INADDR_ANY) &&
1164             !ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
1165                 return -EINVAL;
1166
1167         c = ipmr_cache_alloc();
1168         if (!c)
1169                 return -ENOMEM;
1170
1171         c->mfc_origin = mfc->mfcc_origin.s_addr;
1172         c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
1173         c->mfc_parent = mfc->mfcc_parent;
1174         ipmr_update_thresholds(mrt, c, mfc->mfcc_ttls);
1175         if (!mrtsock)
1176                 c->mfc_flags |= MFC_STATIC;
1177
1178         list_add_rcu(&c->list, &mrt->mfc_cache_array[line]);
1179
1180         /*
1181          *      Check to see if we resolved a queued list. If so we
1182          *      need to send on the frames and tidy up.
1183          */
1184         found = false;
1185         spin_lock_bh(&mfc_unres_lock);
1186         list_for_each_entry(uc, &mrt->mfc_unres_queue, list) {
1187                 if (uc->mfc_origin == c->mfc_origin &&
1188                     uc->mfc_mcastgrp == c->mfc_mcastgrp) {
1189                         list_del(&uc->list);
1190                         atomic_dec(&mrt->cache_resolve_queue_len);
1191                         found = true;
1192                         break;
1193                 }
1194         }
1195         if (list_empty(&mrt->mfc_unres_queue))
1196                 del_timer(&mrt->ipmr_expire_timer);
1197         spin_unlock_bh(&mfc_unres_lock);
1198
1199         if (found) {
1200                 ipmr_cache_resolve(net, mrt, uc, c);
1201                 ipmr_cache_free(uc);
1202         }
1203         mroute_netlink_event(mrt, c, RTM_NEWROUTE);
1204         return 0;
1205 }
1206
1207 /*
1208  *      Close the multicast socket, and clear the vif tables etc
1209  */
1210
1211 static void mroute_clean_tables(struct mr_table *mrt)
1212 {
1213         int i;
1214         LIST_HEAD(list);
1215         struct mfc_cache *c, *next;
1216
1217         /* Shut down all active vif entries */
1218
1219         for (i = 0; i < mrt->maxvif; i++) {
1220                 if (!(mrt->vif_table[i].flags & VIFF_STATIC))
1221                         vif_delete(mrt, i, 0, &list);
1222         }
1223         unregister_netdevice_many(&list);
1224
1225         /* Wipe the cache */
1226
1227         for (i = 0; i < MFC_LINES; i++) {
1228                 list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[i], list) {
1229                         if (c->mfc_flags & MFC_STATIC)
1230                                 continue;
1231                         list_del_rcu(&c->list);
1232                         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1233                         ipmr_cache_free(c);
1234                 }
1235         }
1236
1237         if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
1238                 spin_lock_bh(&mfc_unres_lock);
1239                 list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
1240                         list_del(&c->list);
1241                         mroute_netlink_event(mrt, c, RTM_DELROUTE);
1242                         ipmr_destroy_unres(mrt, c);
1243                 }
1244                 spin_unlock_bh(&mfc_unres_lock);
1245         }
1246 }
1247
1248 /* called from ip_ra_control(), before an RCU grace period,
1249  * we dont need to call synchronize_rcu() here
1250  */
1251 static void mrtsock_destruct(struct sock *sk)
1252 {
1253         struct net *net = sock_net(sk);
1254         struct mr_table *mrt;
1255
1256         rtnl_lock();
1257         ipmr_for_each_table(mrt, net) {
1258                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1259                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
1260                         inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
1261                                                     NETCONFA_IFINDEX_ALL,
1262                                                     net->ipv4.devconf_all);
1263                         RCU_INIT_POINTER(mrt->mroute_sk, NULL);
1264                         mroute_clean_tables(mrt);
1265                 }
1266         }
1267         rtnl_unlock();
1268 }
1269
1270 /*
1271  *      Socket options and virtual interface manipulation. The whole
1272  *      virtual interface system is a complete heap, but unfortunately
1273  *      that's how BSD mrouted happens to think. Maybe one day with a proper
1274  *      MOSPF/PIM router set up we can clean this up.
1275  */
1276
1277 int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsigned int optlen)
1278 {
1279         int ret, parent = 0;
1280         struct vifctl vif;
1281         struct mfcctl mfc;
1282         struct net *net = sock_net(sk);
1283         struct mr_table *mrt;
1284
1285         if (sk->sk_type != SOCK_RAW ||
1286             inet_sk(sk)->inet_num != IPPROTO_IGMP)
1287                 return -EOPNOTSUPP;
1288
1289         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1290         if (!mrt)
1291                 return -ENOENT;
1292
1293         if (optname != MRT_INIT) {
1294                 if (sk != rcu_access_pointer(mrt->mroute_sk) &&
1295                     !ns_capable(net->user_ns, CAP_NET_ADMIN))
1296                         return -EACCES;
1297         }
1298
1299         switch (optname) {
1300         case MRT_INIT:
1301                 if (optlen != sizeof(int))
1302                         return -EINVAL;
1303
1304                 rtnl_lock();
1305                 if (rtnl_dereference(mrt->mroute_sk)) {
1306                         rtnl_unlock();
1307                         return -EADDRINUSE;
1308                 }
1309
1310                 ret = ip_ra_control(sk, 1, mrtsock_destruct);
1311                 if (ret == 0) {
1312                         rcu_assign_pointer(mrt->mroute_sk, sk);
1313                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
1314                         inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
1315                                                     NETCONFA_IFINDEX_ALL,
1316                                                     net->ipv4.devconf_all);
1317                 }
1318                 rtnl_unlock();
1319                 return ret;
1320         case MRT_DONE:
1321                 if (sk != rcu_access_pointer(mrt->mroute_sk))
1322                         return -EACCES;
1323                 return ip_ra_control(sk, 0, NULL);
1324         case MRT_ADD_VIF:
1325         case MRT_DEL_VIF:
1326                 if (optlen != sizeof(vif))
1327                         return -EINVAL;
1328                 if (copy_from_user(&vif, optval, sizeof(vif)))
1329                         return -EFAULT;
1330                 if (vif.vifc_vifi >= MAXVIFS)
1331                         return -ENFILE;
1332                 rtnl_lock();
1333                 if (optname == MRT_ADD_VIF) {
1334                         ret = vif_add(net, mrt, &vif,
1335                                       sk == rtnl_dereference(mrt->mroute_sk));
1336                 } else {
1337                         ret = vif_delete(mrt, vif.vifc_vifi, 0, NULL);
1338                 }
1339                 rtnl_unlock();
1340                 return ret;
1341
1342                 /*
1343                  *      Manipulate the forwarding caches. These live
1344                  *      in a sort of kernel/user symbiosis.
1345                  */
1346         case MRT_ADD_MFC:
1347         case MRT_DEL_MFC:
1348                 parent = -1;
1349         case MRT_ADD_MFC_PROXY:
1350         case MRT_DEL_MFC_PROXY:
1351                 if (optlen != sizeof(mfc))
1352                         return -EINVAL;
1353                 if (copy_from_user(&mfc, optval, sizeof(mfc)))
1354                         return -EFAULT;
1355                 if (parent == 0)
1356                         parent = mfc.mfcc_parent;
1357                 rtnl_lock();
1358                 if (optname == MRT_DEL_MFC || optname == MRT_DEL_MFC_PROXY)
1359                         ret = ipmr_mfc_delete(mrt, &mfc, parent);
1360                 else
1361                         ret = ipmr_mfc_add(net, mrt, &mfc,
1362                                            sk == rtnl_dereference(mrt->mroute_sk),
1363                                            parent);
1364                 rtnl_unlock();
1365                 return ret;
1366                 /*
1367                  *      Control PIM assert.
1368                  */
1369         case MRT_ASSERT:
1370         {
1371                 int v;
1372                 if (optlen != sizeof(v))
1373                         return -EINVAL;
1374                 if (get_user(v, (int __user *)optval))
1375                         return -EFAULT;
1376                 mrt->mroute_do_assert = v;
1377                 return 0;
1378         }
1379 #ifdef CONFIG_IP_PIMSM
1380         case MRT_PIM:
1381         {
1382                 int v;
1383
1384                 if (optlen != sizeof(v))
1385                         return -EINVAL;
1386                 if (get_user(v, (int __user *)optval))
1387                         return -EFAULT;
1388                 v = !!v;
1389
1390                 rtnl_lock();
1391                 ret = 0;
1392                 if (v != mrt->mroute_do_pim) {
1393                         mrt->mroute_do_pim = v;
1394                         mrt->mroute_do_assert = v;
1395                 }
1396                 rtnl_unlock();
1397                 return ret;
1398         }
1399 #endif
1400 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
1401         case MRT_TABLE:
1402         {
1403                 u32 v;
1404
1405                 if (optlen != sizeof(u32))
1406                         return -EINVAL;
1407                 if (get_user(v, (u32 __user *)optval))
1408                         return -EFAULT;
1409
1410                 /* "pimreg%u" should not exceed 16 bytes (IFNAMSIZ) */
1411                 if (v != RT_TABLE_DEFAULT && v >= 1000000000)
1412                         return -EINVAL;
1413
1414                 rtnl_lock();
1415                 ret = 0;
1416                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
1417                         ret = -EBUSY;
1418                 } else {
1419                         if (!ipmr_new_table(net, v))
1420                                 ret = -ENOMEM;
1421                         else
1422                                 raw_sk(sk)->ipmr_table = v;
1423                 }
1424                 rtnl_unlock();
1425                 return ret;
1426         }
1427 #endif
1428         /*
1429          *      Spurious command, or MRT_VERSION which you cannot
1430          *      set.
1431          */
1432         default:
1433                 return -ENOPROTOOPT;
1434         }
1435 }
1436
1437 /*
1438  *      Getsock opt support for the multicast routing system.
1439  */
1440
1441 int ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int __user *optlen)
1442 {
1443         int olr;
1444         int val;
1445         struct net *net = sock_net(sk);
1446         struct mr_table *mrt;
1447
1448         if (sk->sk_type != SOCK_RAW ||
1449             inet_sk(sk)->inet_num != IPPROTO_IGMP)
1450                 return -EOPNOTSUPP;
1451
1452         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1453         if (!mrt)
1454                 return -ENOENT;
1455
1456         if (optname != MRT_VERSION &&
1457 #ifdef CONFIG_IP_PIMSM
1458            optname != MRT_PIM &&
1459 #endif
1460            optname != MRT_ASSERT)
1461                 return -ENOPROTOOPT;
1462
1463         if (get_user(olr, optlen))
1464                 return -EFAULT;
1465
1466         olr = min_t(unsigned int, olr, sizeof(int));
1467         if (olr < 0)
1468                 return -EINVAL;
1469
1470         if (put_user(olr, optlen))
1471                 return -EFAULT;
1472         if (optname == MRT_VERSION)
1473                 val = 0x0305;
1474 #ifdef CONFIG_IP_PIMSM
1475         else if (optname == MRT_PIM)
1476                 val = mrt->mroute_do_pim;
1477 #endif
1478         else
1479                 val = mrt->mroute_do_assert;
1480         if (copy_to_user(optval, &val, olr))
1481                 return -EFAULT;
1482         return 0;
1483 }
1484
1485 /*
1486  *      The IP multicast ioctl support routines.
1487  */
1488
1489 int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg)
1490 {
1491         struct sioc_sg_req sr;
1492         struct sioc_vif_req vr;
1493         struct vif_device *vif;
1494         struct mfc_cache *c;
1495         struct net *net = sock_net(sk);
1496         struct mr_table *mrt;
1497
1498         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1499         if (!mrt)
1500                 return -ENOENT;
1501
1502         switch (cmd) {
1503         case SIOCGETVIFCNT:
1504                 if (copy_from_user(&vr, arg, sizeof(vr)))
1505                         return -EFAULT;
1506                 if (vr.vifi >= mrt->maxvif)
1507                         return -EINVAL;
1508                 read_lock(&mrt_lock);
1509                 vif = &mrt->vif_table[vr.vifi];
1510                 if (VIF_EXISTS(mrt, vr.vifi)) {
1511                         vr.icount = vif->pkt_in;
1512                         vr.ocount = vif->pkt_out;
1513                         vr.ibytes = vif->bytes_in;
1514                         vr.obytes = vif->bytes_out;
1515                         read_unlock(&mrt_lock);
1516
1517                         if (copy_to_user(arg, &vr, sizeof(vr)))
1518                                 return -EFAULT;
1519                         return 0;
1520                 }
1521                 read_unlock(&mrt_lock);
1522                 return -EADDRNOTAVAIL;
1523         case SIOCGETSGCNT:
1524                 if (copy_from_user(&sr, arg, sizeof(sr)))
1525                         return -EFAULT;
1526
1527                 rcu_read_lock();
1528                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1529                 if (c) {
1530                         sr.pktcnt = c->mfc_un.res.pkt;
1531                         sr.bytecnt = c->mfc_un.res.bytes;
1532                         sr.wrong_if = c->mfc_un.res.wrong_if;
1533                         rcu_read_unlock();
1534
1535                         if (copy_to_user(arg, &sr, sizeof(sr)))
1536                                 return -EFAULT;
1537                         return 0;
1538                 }
1539                 rcu_read_unlock();
1540                 return -EADDRNOTAVAIL;
1541         default:
1542                 return -ENOIOCTLCMD;
1543         }
1544 }
1545
1546 #ifdef CONFIG_COMPAT
1547 struct compat_sioc_sg_req {
1548         struct in_addr src;
1549         struct in_addr grp;
1550         compat_ulong_t pktcnt;
1551         compat_ulong_t bytecnt;
1552         compat_ulong_t wrong_if;
1553 };
1554
1555 struct compat_sioc_vif_req {
1556         vifi_t  vifi;           /* Which iface */
1557         compat_ulong_t icount;
1558         compat_ulong_t ocount;
1559         compat_ulong_t ibytes;
1560         compat_ulong_t obytes;
1561 };
1562
1563 int ipmr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
1564 {
1565         struct compat_sioc_sg_req sr;
1566         struct compat_sioc_vif_req vr;
1567         struct vif_device *vif;
1568         struct mfc_cache *c;
1569         struct net *net = sock_net(sk);
1570         struct mr_table *mrt;
1571
1572         mrt = ipmr_get_table(net, raw_sk(sk)->ipmr_table ? : RT_TABLE_DEFAULT);
1573         if (!mrt)
1574                 return -ENOENT;
1575
1576         switch (cmd) {
1577         case SIOCGETVIFCNT:
1578                 if (copy_from_user(&vr, arg, sizeof(vr)))
1579                         return -EFAULT;
1580                 if (vr.vifi >= mrt->maxvif)
1581                         return -EINVAL;
1582                 read_lock(&mrt_lock);
1583                 vif = &mrt->vif_table[vr.vifi];
1584                 if (VIF_EXISTS(mrt, vr.vifi)) {
1585                         vr.icount = vif->pkt_in;
1586                         vr.ocount = vif->pkt_out;
1587                         vr.ibytes = vif->bytes_in;
1588                         vr.obytes = vif->bytes_out;
1589                         read_unlock(&mrt_lock);
1590
1591                         if (copy_to_user(arg, &vr, sizeof(vr)))
1592                                 return -EFAULT;
1593                         return 0;
1594                 }
1595                 read_unlock(&mrt_lock);
1596                 return -EADDRNOTAVAIL;
1597         case SIOCGETSGCNT:
1598                 if (copy_from_user(&sr, arg, sizeof(sr)))
1599                         return -EFAULT;
1600
1601                 rcu_read_lock();
1602                 c = ipmr_cache_find(mrt, sr.src.s_addr, sr.grp.s_addr);
1603                 if (c) {
1604                         sr.pktcnt = c->mfc_un.res.pkt;
1605                         sr.bytecnt = c->mfc_un.res.bytes;
1606                         sr.wrong_if = c->mfc_un.res.wrong_if;
1607                         rcu_read_unlock();
1608
1609                         if (copy_to_user(arg, &sr, sizeof(sr)))
1610                                 return -EFAULT;
1611                         return 0;
1612                 }
1613                 rcu_read_unlock();
1614                 return -EADDRNOTAVAIL;
1615         default:
1616                 return -ENOIOCTLCMD;
1617         }
1618 }
1619 #endif
1620
1621
1622 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
1623 {
1624         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1625         struct net *net = dev_net(dev);
1626         struct mr_table *mrt;
1627         struct vif_device *v;
1628         int ct;
1629
1630         if (event != NETDEV_UNREGISTER)
1631                 return NOTIFY_DONE;
1632
1633         ipmr_for_each_table(mrt, net) {
1634                 v = &mrt->vif_table[0];
1635                 for (ct = 0; ct < mrt->maxvif; ct++, v++) {
1636                         if (v->dev == dev)
1637                                 vif_delete(mrt, ct, 1, NULL);
1638                 }
1639         }
1640         return NOTIFY_DONE;
1641 }
1642
1643
1644 static struct notifier_block ip_mr_notifier = {
1645         .notifier_call = ipmr_device_event,
1646 };
1647
1648 /*
1649  *      Encapsulate a packet by attaching a valid IPIP header to it.
1650  *      This avoids tunnel drivers and other mess and gives us the speed so
1651  *      important for multicast video.
1652  */
1653
1654 static void ip_encap(struct net *net, struct sk_buff *skb,
1655                      __be32 saddr, __be32 daddr)
1656 {
1657         struct iphdr *iph;
1658         const struct iphdr *old_iph = ip_hdr(skb);
1659
1660         skb_push(skb, sizeof(struct iphdr));
1661         skb->transport_header = skb->network_header;
1662         skb_reset_network_header(skb);
1663         iph = ip_hdr(skb);
1664
1665         iph->version    =       4;
1666         iph->tos        =       old_iph->tos;
1667         iph->ttl        =       old_iph->ttl;
1668         iph->frag_off   =       0;
1669         iph->daddr      =       daddr;
1670         iph->saddr      =       saddr;
1671         iph->protocol   =       IPPROTO_IPIP;
1672         iph->ihl        =       5;
1673         iph->tot_len    =       htons(skb->len);
1674         ip_select_ident(net, skb, NULL);
1675         ip_send_check(iph);
1676
1677         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1678         nf_reset(skb);
1679 }
1680
1681 static inline int ipmr_forward_finish(struct sock *sk, struct sk_buff *skb)
1682 {
1683         struct ip_options *opt = &(IPCB(skb)->opt);
1684
1685         IP_INC_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTFORWDATAGRAMS);
1686         IP_ADD_STATS_BH(dev_net(skb_dst(skb)->dev), IPSTATS_MIB_OUTOCTETS, skb->len);
1687
1688         if (unlikely(opt->optlen))
1689                 ip_forward_options(skb);
1690
1691         return dst_output_sk(sk, skb);
1692 }
1693
1694 /*
1695  *      Processing handlers for ipmr_forward
1696  */
1697
1698 static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
1699                             struct sk_buff *skb, struct mfc_cache *c, int vifi)
1700 {
1701         const struct iphdr *iph = ip_hdr(skb);
1702         struct vif_device *vif = &mrt->vif_table[vifi];
1703         struct net_device *dev;
1704         struct rtable *rt;
1705         struct flowi4 fl4;
1706         int    encap = 0;
1707
1708         if (!vif->dev)
1709                 goto out_free;
1710
1711 #ifdef CONFIG_IP_PIMSM
1712         if (vif->flags & VIFF_REGISTER) {
1713                 vif->pkt_out++;
1714                 vif->bytes_out += skb->len;
1715                 vif->dev->stats.tx_bytes += skb->len;
1716                 vif->dev->stats.tx_packets++;
1717                 ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
1718                 goto out_free;
1719         }
1720 #endif
1721
1722         if (vif->flags & VIFF_TUNNEL) {
1723                 rt = ip_route_output_ports(net, &fl4, NULL,
1724                                            vif->remote, vif->local,
1725                                            0, 0,
1726                                            IPPROTO_IPIP,
1727                                            RT_TOS(iph->tos), vif->link);
1728                 if (IS_ERR(rt))
1729                         goto out_free;
1730                 encap = sizeof(struct iphdr);
1731         } else {
1732                 rt = ip_route_output_ports(net, &fl4, NULL, iph->daddr, 0,
1733                                            0, 0,
1734                                            IPPROTO_IPIP,
1735                                            RT_TOS(iph->tos), vif->link);
1736                 if (IS_ERR(rt))
1737                         goto out_free;
1738         }
1739
1740         dev = rt->dst.dev;
1741
1742         if (skb->len+encap > dst_mtu(&rt->dst) && (ntohs(iph->frag_off) & IP_DF)) {
1743                 /* Do not fragment multicasts. Alas, IPv4 does not
1744                  * allow to send ICMP, so that packets will disappear
1745                  * to blackhole.
1746                  */
1747
1748                 IP_INC_STATS_BH(dev_net(dev), IPSTATS_MIB_FRAGFAILS);
1749                 ip_rt_put(rt);
1750                 goto out_free;
1751         }
1752
1753         encap += LL_RESERVED_SPACE(dev) + rt->dst.header_len;
1754
1755         if (skb_cow(skb, encap)) {
1756                 ip_rt_put(rt);
1757                 goto out_free;
1758         }
1759
1760         vif->pkt_out++;
1761         vif->bytes_out += skb->len;
1762
1763         skb_dst_drop(skb);
1764         skb_dst_set(skb, &rt->dst);
1765         ip_decrease_ttl(ip_hdr(skb));
1766
1767         /* FIXME: forward and output firewalls used to be called here.
1768          * What do we do with netfilter? -- RR
1769          */
1770         if (vif->flags & VIFF_TUNNEL) {
1771                 ip_encap(net, skb, vif->local, vif->remote);
1772                 /* FIXME: extra output firewall step used to be here. --RR */
1773                 vif->dev->stats.tx_packets++;
1774                 vif->dev->stats.tx_bytes += skb->len;
1775         }
1776
1777         IPCB(skb)->flags |= IPSKB_FORWARDED;
1778
1779         /*
1780          * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
1781          * not only before forwarding, but after forwarding on all output
1782          * interfaces. It is clear, if mrouter runs a multicasting
1783          * program, it should receive packets not depending to what interface
1784          * program is joined.
1785          * If we will not make it, the program will have to join on all
1786          * interfaces. On the other hand, multihoming host (or router, but
1787          * not mrouter) cannot join to more than one interface - it will
1788          * result in receiving multiple packets.
1789          */
1790         NF_HOOK(NFPROTO_IPV4, NF_INET_FORWARD, NULL, skb,
1791                 skb->dev, dev,
1792                 ipmr_forward_finish);
1793         return;
1794
1795 out_free:
1796         kfree_skb(skb);
1797 }
1798
1799 static int ipmr_find_vif(struct mr_table *mrt, struct net_device *dev)
1800 {
1801         int ct;
1802
1803         for (ct = mrt->maxvif-1; ct >= 0; ct--) {
1804                 if (mrt->vif_table[ct].dev == dev)
1805                         break;
1806         }
1807         return ct;
1808 }
1809
1810 /* "local" means that we should preserve one skb (for local delivery) */
1811
1812 static void ip_mr_forward(struct net *net, struct mr_table *mrt,
1813                           struct sk_buff *skb, struct mfc_cache *cache,
1814                           int local)
1815 {
1816         int psend = -1;
1817         int vif, ct;
1818         int true_vifi = ipmr_find_vif(mrt, skb->dev);
1819
1820         vif = cache->mfc_parent;
1821         cache->mfc_un.res.pkt++;
1822         cache->mfc_un.res.bytes += skb->len;
1823
1824         if (cache->mfc_origin == htonl(INADDR_ANY) && true_vifi >= 0) {
1825                 struct mfc_cache *cache_proxy;
1826
1827                 /* For an (*,G) entry, we only check that the incomming
1828                  * interface is part of the static tree.
1829                  */
1830                 cache_proxy = ipmr_cache_find_any_parent(mrt, vif);
1831                 if (cache_proxy &&
1832                     cache_proxy->mfc_un.res.ttls[true_vifi] < 255)
1833                         goto forward;
1834         }
1835
1836         /*
1837          * Wrong interface: drop packet and (maybe) send PIM assert.
1838          */
1839         if (mrt->vif_table[vif].dev != skb->dev) {
1840                 if (rt_is_output_route(skb_rtable(skb))) {
1841                         /* It is our own packet, looped back.
1842                          * Very complicated situation...
1843                          *
1844                          * The best workaround until routing daemons will be
1845                          * fixed is not to redistribute packet, if it was
1846                          * send through wrong interface. It means, that
1847                          * multicast applications WILL NOT work for
1848                          * (S,G), which have default multicast route pointing
1849                          * to wrong oif. In any case, it is not a good
1850                          * idea to use multicasting applications on router.
1851                          */
1852                         goto dont_forward;
1853                 }
1854
1855                 cache->mfc_un.res.wrong_if++;
1856
1857                 if (true_vifi >= 0 && mrt->mroute_do_assert &&
1858                     /* pimsm uses asserts, when switching from RPT to SPT,
1859                      * so that we cannot check that packet arrived on an oif.
1860                      * It is bad, but otherwise we would need to move pretty
1861                      * large chunk of pimd to kernel. Ough... --ANK
1862                      */
1863                     (mrt->mroute_do_pim ||
1864                      cache->mfc_un.res.ttls[true_vifi] < 255) &&
1865                     time_after(jiffies,
1866                                cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) {
1867                         cache->mfc_un.res.last_assert = jiffies;
1868                         ipmr_cache_report(mrt, skb, true_vifi, IGMPMSG_WRONGVIF);
1869                 }
1870                 goto dont_forward;
1871         }
1872
1873 forward:
1874         mrt->vif_table[vif].pkt_in++;
1875         mrt->vif_table[vif].bytes_in += skb->len;
1876
1877         /*
1878          *      Forward the frame
1879          */
1880         if (cache->mfc_origin == htonl(INADDR_ANY) &&
1881             cache->mfc_mcastgrp == htonl(INADDR_ANY)) {
1882                 if (true_vifi >= 0 &&
1883                     true_vifi != cache->mfc_parent &&
1884                     ip_hdr(skb)->ttl >
1885                                 cache->mfc_un.res.ttls[cache->mfc_parent]) {
1886                         /* It's an (*,*) entry and the packet is not coming from
1887                          * the upstream: forward the packet to the upstream
1888                          * only.
1889                          */
1890                         psend = cache->mfc_parent;
1891                         goto last_forward;
1892                 }
1893                 goto dont_forward;
1894         }
1895         for (ct = cache->mfc_un.res.maxvif - 1;
1896              ct >= cache->mfc_un.res.minvif; ct--) {
1897                 /* For (*,G) entry, don't forward to the incoming interface */
1898                 if ((cache->mfc_origin != htonl(INADDR_ANY) ||
1899                      ct != true_vifi) &&
1900                     ip_hdr(skb)->ttl > cache->mfc_un.res.ttls[ct]) {
1901                         if (psend != -1) {
1902                                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1903
1904                                 if (skb2)
1905                                         ipmr_queue_xmit(net, mrt, skb2, cache,
1906                                                         psend);
1907                         }
1908                         psend = ct;
1909                 }
1910         }
1911 last_forward:
1912         if (psend != -1) {
1913                 if (local) {
1914                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
1915
1916                         if (skb2)
1917                                 ipmr_queue_xmit(net, mrt, skb2, cache, psend);
1918                 } else {
1919                         ipmr_queue_xmit(net, mrt, skb, cache, psend);
1920                         return;
1921                 }
1922         }
1923
1924 dont_forward:
1925         if (!local)
1926                 kfree_skb(skb);
1927 }
1928
1929 static struct mr_table *ipmr_rt_fib_lookup(struct net *net, struct sk_buff *skb)
1930 {
1931         struct rtable *rt = skb_rtable(skb);
1932         struct iphdr *iph = ip_hdr(skb);
1933         struct flowi4 fl4 = {
1934                 .daddr = iph->daddr,
1935                 .saddr = iph->saddr,
1936                 .flowi4_tos = RT_TOS(iph->tos),
1937                 .flowi4_oif = (rt_is_output_route(rt) ?
1938                                skb->dev->ifindex : 0),
1939                 .flowi4_iif = (rt_is_output_route(rt) ?
1940                                LOOPBACK_IFINDEX :
1941                                skb->dev->ifindex),
1942                 .flowi4_mark = skb->mark,
1943         };
1944         struct mr_table *mrt;
1945         int err;
1946
1947         err = ipmr_fib_lookup(net, &fl4, &mrt);
1948         if (err)
1949                 return ERR_PTR(err);
1950         return mrt;
1951 }
1952
1953 /*
1954  *      Multicast packets for forwarding arrive here
1955  *      Called with rcu_read_lock();
1956  */
1957
1958 int ip_mr_input(struct sk_buff *skb)
1959 {
1960         struct mfc_cache *cache;
1961         struct net *net = dev_net(skb->dev);
1962         int local = skb_rtable(skb)->rt_flags & RTCF_LOCAL;
1963         struct mr_table *mrt;
1964
1965         /* Packet is looped back after forward, it should not be
1966          * forwarded second time, but still can be delivered locally.
1967          */
1968         if (IPCB(skb)->flags & IPSKB_FORWARDED)
1969                 goto dont_forward;
1970
1971         mrt = ipmr_rt_fib_lookup(net, skb);
1972         if (IS_ERR(mrt)) {
1973                 kfree_skb(skb);
1974                 return PTR_ERR(mrt);
1975         }
1976         if (!local) {
1977                 if (IPCB(skb)->opt.router_alert) {
1978                         if (ip_call_ra_chain(skb))
1979                                 return 0;
1980                 } else if (ip_hdr(skb)->protocol == IPPROTO_IGMP) {
1981                         /* IGMPv1 (and broken IGMPv2 implementations sort of
1982                          * Cisco IOS <= 11.2(8)) do not put router alert
1983                          * option to IGMP packets destined to routable
1984                          * groups. It is very bad, because it means
1985                          * that we can forward NO IGMP messages.
1986                          */
1987                         struct sock *mroute_sk;
1988
1989                         mroute_sk = rcu_dereference(mrt->mroute_sk);
1990                         if (mroute_sk) {
1991                                 nf_reset(skb);
1992                                 raw_rcv(mroute_sk, skb);
1993                                 return 0;
1994                         }
1995                     }
1996         }
1997
1998         /* already under rcu_read_lock() */
1999         cache = ipmr_cache_find(mrt, ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
2000         if (!cache) {
2001                 int vif = ipmr_find_vif(mrt, skb->dev);
2002
2003                 if (vif >= 0)
2004                         cache = ipmr_cache_find_any(mrt, ip_hdr(skb)->daddr,
2005                                                     vif);
2006         }
2007
2008         /*
2009          *      No usable cache entry
2010          */
2011         if (!cache) {
2012                 int vif;
2013
2014                 if (local) {
2015                         struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
2016                         ip_local_deliver(skb);
2017                         if (!skb2)
2018                                 return -ENOBUFS;
2019                         skb = skb2;
2020                 }
2021
2022                 read_lock(&mrt_lock);
2023                 vif = ipmr_find_vif(mrt, skb->dev);
2024                 if (vif >= 0) {
2025                         int err2 = ipmr_cache_unresolved(mrt, vif, skb);
2026                         read_unlock(&mrt_lock);
2027
2028                         return err2;
2029                 }
2030                 read_unlock(&mrt_lock);
2031                 kfree_skb(skb);
2032                 return -ENODEV;
2033         }
2034
2035         read_lock(&mrt_lock);
2036         ip_mr_forward(net, mrt, skb, cache, local);
2037         read_unlock(&mrt_lock);
2038
2039         if (local)
2040                 return ip_local_deliver(skb);
2041
2042         return 0;
2043
2044 dont_forward:
2045         if (local)
2046                 return ip_local_deliver(skb);
2047         kfree_skb(skb);
2048         return 0;
2049 }
2050
2051 #ifdef CONFIG_IP_PIMSM
2052 /* called with rcu_read_lock() */
2053 static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
2054                      unsigned int pimlen)
2055 {
2056         struct net_device *reg_dev = NULL;
2057         struct iphdr *encap;
2058
2059         encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
2060         /*
2061          * Check that:
2062          * a. packet is really sent to a multicast group
2063          * b. packet is not a NULL-REGISTER
2064          * c. packet is not truncated
2065          */
2066         if (!ipv4_is_multicast(encap->daddr) ||
2067             encap->tot_len == 0 ||
2068             ntohs(encap->tot_len) + pimlen > skb->len)
2069                 return 1;
2070
2071         read_lock(&mrt_lock);
2072         if (mrt->mroute_reg_vif_num >= 0)
2073                 reg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
2074         read_unlock(&mrt_lock);
2075
2076         if (!reg_dev)
2077                 return 1;
2078
2079         skb->mac_header = skb->network_header;
2080         skb_pull(skb, (u8 *)encap - skb->data);
2081         skb_reset_network_header(skb);
2082         skb->protocol = htons(ETH_P_IP);
2083         skb->ip_summed = CHECKSUM_NONE;
2084
2085         skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
2086
2087         netif_rx(skb);
2088
2089         return NET_RX_SUCCESS;
2090 }
2091 #endif
2092
2093 #ifdef CONFIG_IP_PIMSM_V1
2094 /*
2095  * Handle IGMP messages of PIMv1
2096  */
2097
2098 int pim_rcv_v1(struct sk_buff *skb)
2099 {
2100         struct igmphdr *pim;
2101         struct net *net = dev_net(skb->dev);
2102         struct mr_table *mrt;
2103
2104         if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2105                 goto drop;
2106
2107         pim = igmp_hdr(skb);
2108
2109         mrt = ipmr_rt_fib_lookup(net, skb);
2110         if (IS_ERR(mrt))
2111                 goto drop;
2112         if (!mrt->mroute_do_pim ||
2113             pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
2114                 goto drop;
2115
2116         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2117 drop:
2118                 kfree_skb(skb);
2119         }
2120         return 0;
2121 }
2122 #endif
2123
2124 #ifdef CONFIG_IP_PIMSM_V2
2125 static int pim_rcv(struct sk_buff *skb)
2126 {
2127         struct pimreghdr *pim;
2128         struct net *net = dev_net(skb->dev);
2129         struct mr_table *mrt;
2130
2131         if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(struct iphdr)))
2132                 goto drop;
2133
2134         pim = (struct pimreghdr *)skb_transport_header(skb);
2135         if (pim->type != ((PIM_VERSION << 4) | (PIM_REGISTER)) ||
2136             (pim->flags & PIM_NULL_REGISTER) ||
2137             (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
2138              csum_fold(skb_checksum(skb, 0, skb->len, 0))))
2139                 goto drop;
2140
2141         mrt = ipmr_rt_fib_lookup(net, skb);
2142         if (IS_ERR(mrt))
2143                 goto drop;
2144         if (__pim_rcv(mrt, skb, sizeof(*pim))) {
2145 drop:
2146                 kfree_skb(skb);
2147         }
2148         return 0;
2149 }
2150 #endif
2151
2152 static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2153                               struct mfc_cache *c, struct rtmsg *rtm)
2154 {
2155         int ct;
2156         struct rtnexthop *nhp;
2157         struct nlattr *mp_attr;
2158         struct rta_mfc_stats mfcs;
2159
2160         /* If cache is unresolved, don't try to parse IIF and OIF */
2161         if (c->mfc_parent >= MAXVIFS)
2162                 return -ENOENT;
2163
2164         if (VIF_EXISTS(mrt, c->mfc_parent) &&
2165             nla_put_u32(skb, RTA_IIF, mrt->vif_table[c->mfc_parent].dev->ifindex) < 0)
2166                 return -EMSGSIZE;
2167
2168         if (!(mp_attr = nla_nest_start(skb, RTA_MULTIPATH)))
2169                 return -EMSGSIZE;
2170
2171         for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
2172                 if (VIF_EXISTS(mrt, ct) && c->mfc_un.res.ttls[ct] < 255) {
2173                         if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp)))) {
2174                                 nla_nest_cancel(skb, mp_attr);
2175                                 return -EMSGSIZE;
2176                         }
2177
2178                         nhp->rtnh_flags = 0;
2179                         nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
2180                         nhp->rtnh_ifindex = mrt->vif_table[ct].dev->ifindex;
2181                         nhp->rtnh_len = sizeof(*nhp);
2182                 }
2183         }
2184
2185         nla_nest_end(skb, mp_attr);
2186
2187         mfcs.mfcs_packets = c->mfc_un.res.pkt;
2188         mfcs.mfcs_bytes = c->mfc_un.res.bytes;
2189         mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
2190         if (nla_put(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs) < 0)
2191                 return -EMSGSIZE;
2192
2193         rtm->rtm_type = RTN_MULTICAST;
2194         return 1;
2195 }
2196
2197 int ipmr_get_route(struct net *net, struct sk_buff *skb,
2198                    __be32 saddr, __be32 daddr,
2199                    struct rtmsg *rtm, int nowait)
2200 {
2201         struct mfc_cache *cache;
2202         struct mr_table *mrt;
2203         int err;
2204
2205         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2206         if (!mrt)
2207                 return -ENOENT;
2208
2209         rcu_read_lock();
2210         cache = ipmr_cache_find(mrt, saddr, daddr);
2211         if (!cache && skb->dev) {
2212                 int vif = ipmr_find_vif(mrt, skb->dev);
2213
2214                 if (vif >= 0)
2215                         cache = ipmr_cache_find_any(mrt, daddr, vif);
2216         }
2217         if (!cache) {
2218                 struct sk_buff *skb2;
2219                 struct iphdr *iph;
2220                 struct net_device *dev;
2221                 int vif = -1;
2222
2223                 if (nowait) {
2224                         rcu_read_unlock();
2225                         return -EAGAIN;
2226                 }
2227
2228                 dev = skb->dev;
2229                 read_lock(&mrt_lock);
2230                 if (dev)
2231                         vif = ipmr_find_vif(mrt, dev);
2232                 if (vif < 0) {
2233                         read_unlock(&mrt_lock);
2234                         rcu_read_unlock();
2235                         return -ENODEV;
2236                 }
2237                 skb2 = skb_clone(skb, GFP_ATOMIC);
2238                 if (!skb2) {
2239                         read_unlock(&mrt_lock);
2240                         rcu_read_unlock();
2241                         return -ENOMEM;
2242                 }
2243
2244                 skb_push(skb2, sizeof(struct iphdr));
2245                 skb_reset_network_header(skb2);
2246                 iph = ip_hdr(skb2);
2247                 iph->ihl = sizeof(struct iphdr) >> 2;
2248                 iph->saddr = saddr;
2249                 iph->daddr = daddr;
2250                 iph->version = 0;
2251                 err = ipmr_cache_unresolved(mrt, vif, skb2);
2252                 read_unlock(&mrt_lock);
2253                 rcu_read_unlock();
2254                 return err;
2255         }
2256
2257         read_lock(&mrt_lock);
2258         if (!nowait && (rtm->rtm_flags & RTM_F_NOTIFY))
2259                 cache->mfc_flags |= MFC_NOTIFY;
2260         err = __ipmr_fill_mroute(mrt, skb, cache, rtm);
2261         read_unlock(&mrt_lock);
2262         rcu_read_unlock();
2263         return err;
2264 }
2265
2266 static int ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
2267                             u32 portid, u32 seq, struct mfc_cache *c, int cmd,
2268                             int flags)
2269 {
2270         struct nlmsghdr *nlh;
2271         struct rtmsg *rtm;
2272         int err;
2273
2274         nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
2275         if (!nlh)
2276                 return -EMSGSIZE;
2277
2278         rtm = nlmsg_data(nlh);
2279         rtm->rtm_family   = RTNL_FAMILY_IPMR;
2280         rtm->rtm_dst_len  = 32;
2281         rtm->rtm_src_len  = 32;
2282         rtm->rtm_tos      = 0;
2283         rtm->rtm_table    = mrt->id;
2284         if (nla_put_u32(skb, RTA_TABLE, mrt->id))
2285                 goto nla_put_failure;
2286         rtm->rtm_type     = RTN_MULTICAST;
2287         rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
2288         if (c->mfc_flags & MFC_STATIC)
2289                 rtm->rtm_protocol = RTPROT_STATIC;
2290         else
2291                 rtm->rtm_protocol = RTPROT_MROUTED;
2292         rtm->rtm_flags    = 0;
2293
2294         if (nla_put_in_addr(skb, RTA_SRC, c->mfc_origin) ||
2295             nla_put_in_addr(skb, RTA_DST, c->mfc_mcastgrp))
2296                 goto nla_put_failure;
2297         err = __ipmr_fill_mroute(mrt, skb, c, rtm);
2298         /* do not break the dump if cache is unresolved */
2299         if (err < 0 && err != -ENOENT)
2300                 goto nla_put_failure;
2301
2302         nlmsg_end(skb, nlh);
2303         return 0;
2304
2305 nla_put_failure:
2306         nlmsg_cancel(skb, nlh);
2307         return -EMSGSIZE;
2308 }
2309
2310 static size_t mroute_msgsize(bool unresolved, int maxvif)
2311 {
2312         size_t len =
2313                 NLMSG_ALIGN(sizeof(struct rtmsg))
2314                 + nla_total_size(4)     /* RTA_TABLE */
2315                 + nla_total_size(4)     /* RTA_SRC */
2316                 + nla_total_size(4)     /* RTA_DST */
2317                 ;
2318
2319         if (!unresolved)
2320                 len = len
2321                       + nla_total_size(4)       /* RTA_IIF */
2322                       + nla_total_size(0)       /* RTA_MULTIPATH */
2323                       + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
2324                                                 /* RTA_MFC_STATS */
2325                       + nla_total_size(sizeof(struct rta_mfc_stats))
2326                 ;
2327
2328         return len;
2329 }
2330
2331 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
2332                                  int cmd)
2333 {
2334         struct net *net = read_pnet(&mrt->net);
2335         struct sk_buff *skb;
2336         int err = -ENOBUFS;
2337
2338         skb = nlmsg_new(mroute_msgsize(mfc->mfc_parent >= MAXVIFS, mrt->maxvif),
2339                         GFP_ATOMIC);
2340         if (!skb)
2341                 goto errout;
2342
2343         err = ipmr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
2344         if (err < 0)
2345                 goto errout;
2346
2347         rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MROUTE, NULL, GFP_ATOMIC);
2348         return;
2349
2350 errout:
2351         kfree_skb(skb);
2352         if (err < 0)
2353                 rtnl_set_sk_err(net, RTNLGRP_IPV4_MROUTE, err);
2354 }
2355
2356 static int ipmr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
2357 {
2358         struct net *net = sock_net(skb->sk);
2359         struct mr_table *mrt;
2360         struct mfc_cache *mfc;
2361         unsigned int t = 0, s_t;
2362         unsigned int h = 0, s_h;
2363         unsigned int e = 0, s_e;
2364
2365         s_t = cb->args[0];
2366         s_h = cb->args[1];
2367         s_e = cb->args[2];
2368
2369         rcu_read_lock();
2370         ipmr_for_each_table(mrt, net) {
2371                 if (t < s_t)
2372                         goto next_table;
2373                 if (t > s_t)
2374                         s_h = 0;
2375                 for (h = s_h; h < MFC_LINES; h++) {
2376                         list_for_each_entry_rcu(mfc, &mrt->mfc_cache_array[h], list) {
2377                                 if (e < s_e)
2378                                         goto next_entry;
2379                                 if (ipmr_fill_mroute(mrt, skb,
2380                                                      NETLINK_CB(cb->skb).portid,
2381                                                      cb->nlh->nlmsg_seq,
2382                                                      mfc, RTM_NEWROUTE,
2383                                                      NLM_F_MULTI) < 0)
2384                                         goto done;
2385 next_entry:
2386                                 e++;
2387                         }
2388                         e = s_e = 0;
2389                 }
2390                 spin_lock_bh(&mfc_unres_lock);
2391                 list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) {
2392                         if (e < s_e)
2393                                 goto next_entry2;
2394                         if (ipmr_fill_mroute(mrt, skb,
2395                                              NETLINK_CB(cb->skb).portid,
2396                                              cb->nlh->nlmsg_seq,
2397                                              mfc, RTM_NEWROUTE,
2398                                              NLM_F_MULTI) < 0) {
2399                                 spin_unlock_bh(&mfc_unres_lock);
2400                                 goto done;
2401                         }
2402 next_entry2:
2403                         e++;
2404                 }
2405                 spin_unlock_bh(&mfc_unres_lock);
2406                 e = s_e = 0;
2407                 s_h = 0;
2408 next_table:
2409                 t++;
2410         }
2411 done:
2412         rcu_read_unlock();
2413
2414         cb->args[2] = e;
2415         cb->args[1] = h;
2416         cb->args[0] = t;
2417
2418         return skb->len;
2419 }
2420
2421 #ifdef CONFIG_PROC_FS
2422 /*
2423  *      The /proc interfaces to multicast routing :
2424  *      /proc/net/ip_mr_cache & /proc/net/ip_mr_vif
2425  */
2426 struct ipmr_vif_iter {
2427         struct seq_net_private p;
2428         struct mr_table *mrt;
2429         int ct;
2430 };
2431
2432 static struct vif_device *ipmr_vif_seq_idx(struct net *net,
2433                                            struct ipmr_vif_iter *iter,
2434                                            loff_t pos)
2435 {
2436         struct mr_table *mrt = iter->mrt;
2437
2438         for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
2439                 if (!VIF_EXISTS(mrt, iter->ct))
2440                         continue;
2441                 if (pos-- == 0)
2442                         return &mrt->vif_table[iter->ct];
2443         }
2444         return NULL;
2445 }
2446
2447 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos)
2448         __acquires(mrt_lock)
2449 {
2450         struct ipmr_vif_iter *iter = seq->private;
2451         struct net *net = seq_file_net(seq);
2452         struct mr_table *mrt;
2453
2454         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2455         if (!mrt)
2456                 return ERR_PTR(-ENOENT);
2457
2458         iter->mrt = mrt;
2459
2460         read_lock(&mrt_lock);
2461         return *pos ? ipmr_vif_seq_idx(net, seq->private, *pos - 1)
2462                 : SEQ_START_TOKEN;
2463 }
2464
2465 static void *ipmr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2466 {
2467         struct ipmr_vif_iter *iter = seq->private;
2468         struct net *net = seq_file_net(seq);
2469         struct mr_table *mrt = iter->mrt;
2470
2471         ++*pos;
2472         if (v == SEQ_START_TOKEN)
2473                 return ipmr_vif_seq_idx(net, iter, 0);
2474
2475         while (++iter->ct < mrt->maxvif) {
2476                 if (!VIF_EXISTS(mrt, iter->ct))
2477                         continue;
2478                 return &mrt->vif_table[iter->ct];
2479         }
2480         return NULL;
2481 }
2482
2483 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v)
2484         __releases(mrt_lock)
2485 {
2486         read_unlock(&mrt_lock);
2487 }
2488
2489 static int ipmr_vif_seq_show(struct seq_file *seq, void *v)
2490 {
2491         struct ipmr_vif_iter *iter = seq->private;
2492         struct mr_table *mrt = iter->mrt;
2493
2494         if (v == SEQ_START_TOKEN) {
2495                 seq_puts(seq,
2496                          "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags Local    Remote\n");
2497         } else {
2498                 const struct vif_device *vif = v;
2499                 const char *name =  vif->dev ? vif->dev->name : "none";
2500
2501                 seq_printf(seq,
2502                            "%2Zd %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
2503                            vif - mrt->vif_table,
2504                            name, vif->bytes_in, vif->pkt_in,
2505                            vif->bytes_out, vif->pkt_out,
2506                            vif->flags, vif->local, vif->remote);
2507         }
2508         return 0;
2509 }
2510
2511 static const struct seq_operations ipmr_vif_seq_ops = {
2512         .start = ipmr_vif_seq_start,
2513         .next  = ipmr_vif_seq_next,
2514         .stop  = ipmr_vif_seq_stop,
2515         .show  = ipmr_vif_seq_show,
2516 };
2517
2518 static int ipmr_vif_open(struct inode *inode, struct file *file)
2519 {
2520         return seq_open_net(inode, file, &ipmr_vif_seq_ops,
2521                             sizeof(struct ipmr_vif_iter));
2522 }
2523
2524 static const struct file_operations ipmr_vif_fops = {
2525         .owner   = THIS_MODULE,
2526         .open    = ipmr_vif_open,
2527         .read    = seq_read,
2528         .llseek  = seq_lseek,
2529         .release = seq_release_net,
2530 };
2531
2532 struct ipmr_mfc_iter {
2533         struct seq_net_private p;
2534         struct mr_table *mrt;
2535         struct list_head *cache;
2536         int ct;
2537 };
2538
2539
2540 static struct mfc_cache *ipmr_mfc_seq_idx(struct net *net,
2541                                           struct ipmr_mfc_iter *it, loff_t pos)
2542 {
2543         struct mr_table *mrt = it->mrt;
2544         struct mfc_cache *mfc;
2545
2546         rcu_read_lock();
2547         for (it->ct = 0; it->ct < MFC_LINES; it->ct++) {
2548                 it->cache = &mrt->mfc_cache_array[it->ct];
2549                 list_for_each_entry_rcu(mfc, it->cache, list)
2550                         if (pos-- == 0)
2551                                 return mfc;
2552         }
2553         rcu_read_unlock();
2554
2555         spin_lock_bh(&mfc_unres_lock);
2556         it->cache = &mrt->mfc_unres_queue;
2557         list_for_each_entry(mfc, it->cache, list)
2558                 if (pos-- == 0)
2559                         return mfc;
2560         spin_unlock_bh(&mfc_unres_lock);
2561
2562         it->cache = NULL;
2563         return NULL;
2564 }
2565
2566
2567 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
2568 {
2569         struct ipmr_mfc_iter *it = seq->private;
2570         struct net *net = seq_file_net(seq);
2571         struct mr_table *mrt;
2572
2573         mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
2574         if (!mrt)
2575                 return ERR_PTR(-ENOENT);
2576
2577         it->mrt = mrt;
2578         it->cache = NULL;
2579         it->ct = 0;
2580         return *pos ? ipmr_mfc_seq_idx(net, seq->private, *pos - 1)
2581                 : SEQ_START_TOKEN;
2582 }
2583
2584 static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2585 {
2586         struct mfc_cache *mfc = v;
2587         struct ipmr_mfc_iter *it = seq->private;
2588         struct net *net = seq_file_net(seq);
2589         struct mr_table *mrt = it->mrt;
2590
2591         ++*pos;
2592
2593         if (v == SEQ_START_TOKEN)
2594                 return ipmr_mfc_seq_idx(net, seq->private, 0);
2595
2596         if (mfc->list.next != it->cache)
2597                 return list_entry(mfc->list.next, struct mfc_cache, list);
2598
2599         if (it->cache == &mrt->mfc_unres_queue)
2600                 goto end_of_list;
2601
2602         BUG_ON(it->cache != &mrt->mfc_cache_array[it->ct]);
2603
2604         while (++it->ct < MFC_LINES) {
2605                 it->cache = &mrt->mfc_cache_array[it->ct];
2606                 if (list_empty(it->cache))
2607                         continue;
2608                 return list_first_entry(it->cache, struct mfc_cache, list);
2609         }
2610
2611         /* exhausted cache_array, show unresolved */
2612         rcu_read_unlock();
2613         it->cache = &mrt->mfc_unres_queue;
2614         it->ct = 0;
2615
2616         spin_lock_bh(&mfc_unres_lock);
2617         if (!list_empty(it->cache))
2618                 return list_first_entry(it->cache, struct mfc_cache, list);
2619
2620 end_of_list:
2621         spin_unlock_bh(&mfc_unres_lock);
2622         it->cache = NULL;
2623
2624         return NULL;
2625 }
2626
2627 static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
2628 {
2629         struct ipmr_mfc_iter *it = seq->private;
2630         struct mr_table *mrt = it->mrt;
2631
2632         if (it->cache == &mrt->mfc_unres_queue)
2633                 spin_unlock_bh(&mfc_unres_lock);
2634         else if (it->cache == &mrt->mfc_cache_array[it->ct])
2635                 rcu_read_unlock();
2636 }
2637
2638 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
2639 {
2640         int n;
2641
2642         if (v == SEQ_START_TOKEN) {
2643                 seq_puts(seq,
2644                  "Group    Origin   Iif     Pkts    Bytes    Wrong Oifs\n");
2645         } else {
2646                 const struct mfc_cache *mfc = v;
2647                 const struct ipmr_mfc_iter *it = seq->private;
2648                 const struct mr_table *mrt = it->mrt;
2649
2650                 seq_printf(seq, "%08X %08X %-3hd",
2651                            (__force u32) mfc->mfc_mcastgrp,
2652                            (__force u32) mfc->mfc_origin,
2653                            mfc->mfc_parent);
2654
2655                 if (it->cache != &mrt->mfc_unres_queue) {
2656                         seq_printf(seq, " %8lu %8lu %8lu",
2657                                    mfc->mfc_un.res.pkt,
2658                                    mfc->mfc_un.res.bytes,
2659                                    mfc->mfc_un.res.wrong_if);
2660                         for (n = mfc->mfc_un.res.minvif;
2661                              n < mfc->mfc_un.res.maxvif; n++) {
2662                                 if (VIF_EXISTS(mrt, n) &&
2663                                     mfc->mfc_un.res.ttls[n] < 255)
2664                                         seq_printf(seq,
2665                                            " %2d:%-3d",
2666                                            n, mfc->mfc_un.res.ttls[n]);
2667                         }
2668                 } else {
2669                         /* unresolved mfc_caches don't contain
2670                          * pkt, bytes and wrong_if values
2671                          */
2672                         seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
2673                 }
2674                 seq_putc(seq, '\n');
2675         }
2676         return 0;
2677 }
2678
2679 static const struct seq_operations ipmr_mfc_seq_ops = {
2680         .start = ipmr_mfc_seq_start,
2681         .next  = ipmr_mfc_seq_next,
2682         .stop  = ipmr_mfc_seq_stop,
2683         .show  = ipmr_mfc_seq_show,
2684 };
2685
2686 static int ipmr_mfc_open(struct inode *inode, struct file *file)
2687 {
2688         return seq_open_net(inode, file, &ipmr_mfc_seq_ops,
2689                             sizeof(struct ipmr_mfc_iter));
2690 }
2691
2692 static const struct file_operations ipmr_mfc_fops = {
2693         .owner   = THIS_MODULE,
2694         .open    = ipmr_mfc_open,
2695         .read    = seq_read,
2696         .llseek  = seq_lseek,
2697         .release = seq_release_net,
2698 };
2699 #endif
2700
2701 #ifdef CONFIG_IP_PIMSM_V2
2702 static const struct net_protocol pim_protocol = {
2703         .handler        =       pim_rcv,
2704         .netns_ok       =       1,
2705 };
2706 #endif
2707
2708
2709 /*
2710  *      Setup for IP multicast routing
2711  */
2712 static int __net_init ipmr_net_init(struct net *net)
2713 {
2714         int err;
2715
2716         err = ipmr_rules_init(net);
2717         if (err < 0)
2718                 goto fail;
2719
2720 #ifdef CONFIG_PROC_FS
2721         err = -ENOMEM;
2722         if (!proc_create("ip_mr_vif", 0, net->proc_net, &ipmr_vif_fops))
2723                 goto proc_vif_fail;
2724         if (!proc_create("ip_mr_cache", 0, net->proc_net, &ipmr_mfc_fops))
2725                 goto proc_cache_fail;
2726 #endif
2727         return 0;
2728
2729 #ifdef CONFIG_PROC_FS
2730 proc_cache_fail:
2731         remove_proc_entry("ip_mr_vif", net->proc_net);
2732 proc_vif_fail:
2733         ipmr_rules_exit(net);
2734 #endif
2735 fail:
2736         return err;
2737 }
2738
2739 static void __net_exit ipmr_net_exit(struct net *net)
2740 {
2741 #ifdef CONFIG_PROC_FS
2742         remove_proc_entry("ip_mr_cache", net->proc_net);
2743         remove_proc_entry("ip_mr_vif", net->proc_net);
2744 #endif
2745         ipmr_rules_exit(net);
2746 }
2747
2748 static struct pernet_operations ipmr_net_ops = {
2749         .init = ipmr_net_init,
2750         .exit = ipmr_net_exit,
2751 };
2752
2753 int __init ip_mr_init(void)
2754 {
2755         int err;
2756
2757         mrt_cachep = kmem_cache_create("ip_mrt_cache",
2758                                        sizeof(struct mfc_cache),
2759                                        0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,
2760                                        NULL);
2761         if (!mrt_cachep)
2762                 return -ENOMEM;
2763
2764         err = register_pernet_subsys(&ipmr_net_ops);
2765         if (err)
2766                 goto reg_pernet_fail;
2767
2768         err = register_netdevice_notifier(&ip_mr_notifier);
2769         if (err)
2770                 goto reg_notif_fail;
2771 #ifdef CONFIG_IP_PIMSM_V2
2772         if (inet_add_protocol(&pim_protocol, IPPROTO_PIM) < 0) {
2773                 pr_err("%s: can't add PIM protocol\n", __func__);
2774                 err = -EAGAIN;
2775                 goto add_proto_fail;
2776         }
2777 #endif
2778         rtnl_register(RTNL_FAMILY_IPMR, RTM_GETROUTE,
2779                       NULL, ipmr_rtm_dumproute, NULL);
2780         return 0;
2781
2782 #ifdef CONFIG_IP_PIMSM_V2
2783 add_proto_fail:
2784         unregister_netdevice_notifier(&ip_mr_notifier);
2785 #endif
2786 reg_notif_fail:
2787         unregister_pernet_subsys(&ipmr_net_ops);
2788 reg_pernet_fail:
2789         kmem_cache_destroy(mrt_cachep);
2790         return err;
2791 }