net/core/fib_rules.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * net/core/fib_rules.c         Generic Routing Rules
   4  *
   5  * Authors:     Thomas Graf <[email protected]>
   6  */
   7
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <linux/slab.h>
  11 #include <linux/list.h>
  12 #include <linux/module.h>
  13 #include <net/net_namespace.h>
  14 #include <net/inet_dscp.h>
  15 #include <net/sock.h>
  16 #include <net/fib_rules.h>
  17 #include <net/ip_tunnels.h>
  18 #include <linux/indirect_call_wrapper.h>
  19
  20 #if defined(CONFIG_IPV6) && defined(CONFIG_IPV6_MULTIPLE_TABLES)
  21 #ifdef CONFIG_IP_MULTIPLE_TABLES
  22 #define INDIRECT_CALL_MT(f, f2, f1, ...) \
  23         INDIRECT_CALL_INET(f, f2, f1, __VA_ARGS__)
  24 #else
  25 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
  26 #endif
  27 #elif defined(CONFIG_IP_MULTIPLE_TABLES)
  28 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__)
  29 #else
  30 #define INDIRECT_CALL_MT(f, f2, f1, ...) f(__VA_ARGS__)
  31 #endif
  32
  33 static const struct fib_kuid_range fib_kuid_range_unset = {
  34         KUIDT_INIT(0),
  35         KUIDT_INIT(~0),
  36 };
  37
  38 bool fib_rule_matchall(const struct fib_rule *rule)
  39 {
  40         if (rule->iifindex || rule->oifindex || rule->mark || rule->tun_id ||
  41             rule->flags)
  42                 return false;
  43         if (rule->suppress_ifgroup != -1 || rule->suppress_prefixlen != -1)
  44                 return false;
  45         if (!uid_eq(rule->uid_range.start, fib_kuid_range_unset.start) ||
  46             !uid_eq(rule->uid_range.end, fib_kuid_range_unset.end))
  47                 return false;
  48         if (fib_rule_port_range_set(&rule->sport_range))
  49                 return false;
  50         if (fib_rule_port_range_set(&rule->dport_range))
  51                 return false;
  52         return true;
  53 }
  54 EXPORT_SYMBOL_GPL(fib_rule_matchall);
  55
  56 int fib_default_rule_add(struct fib_rules_ops *ops,
  57                          u32 pref, u32 table)
  58 {
  59         struct fib_rule *r;
  60
  61         r = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT);
  62         if (r == NULL)
  63                 return -ENOMEM;
  64
  65         refcount_set(&r->refcnt, 1);
  66         r->action = FR_ACT_TO_TBL;
  67         r->pref = pref;
  68         r->table = table;
  69         r->proto = RTPROT_KERNEL;
  70         r->fr_net = ops->fro_net;
  71         r->uid_range = fib_kuid_range_unset;
  72
  73         r->suppress_prefixlen = -1;
  74         r->suppress_ifgroup = -1;
  75
  76         /* The lock is not required here, the list in unreachable
  77          * at the moment this function is called */
  78         list_add_tail(&r->list, &ops->rules_list);
  79         return 0;
  80 }
  81 EXPORT_SYMBOL(fib_default_rule_add);
  82
  83 static u32 fib_default_rule_pref(struct fib_rules_ops *ops)
  84 {
  85         struct list_head *pos;
  86         struct fib_rule *rule;
  87
  88         if (!list_empty(&ops->rules_list)) {
  89                 pos = ops->rules_list.next;
  90                 if (pos->next != &ops->rules_list) {
  91                         rule = list_entry(pos->next, struct fib_rule, list);
  92                         if (rule->pref)
  93                                 return rule->pref - 1;
  94                 }
  95         }
  96
  97         return 0;
  98 }
  99
 100 static void notify_rule_change(int event, struct fib_rule *rule,
 101                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
 102                                u32 pid);
 103
 104 static struct fib_rules_ops *lookup_rules_ops(const struct net *net,
 105                                               int family)
 106 {
 107         struct fib_rules_ops *ops;
 108
 109         rcu_read_lock();
 110         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
 111                 if (ops->family == family) {
 112                         if (!try_module_get(ops->owner))
 113                                 ops = NULL;
 114                         rcu_read_unlock();
 115                         return ops;
 116                 }
 117         }
 118         rcu_read_unlock();
 119
 120         return NULL;
 121 }
 122
 123 static void rules_ops_put(struct fib_rules_ops *ops)
 124 {
 125         if (ops)
 126                 module_put(ops->owner);
 127 }
 128
 129 static void flush_route_cache(struct fib_rules_ops *ops)
 130 {
 131         if (ops->flush_cache)
 132                 ops->flush_cache(ops);
 133 }
 134
 135 static int __fib_rules_register(struct fib_rules_ops *ops)
 136 {
 137         int err = -EEXIST;
 138         struct fib_rules_ops *o;
 139         struct net *net;
 140
 141         net = ops->fro_net;
 142
 143         if (ops->rule_size < sizeof(struct fib_rule))
 144                 return -EINVAL;
 145
 146         if (ops->match == NULL || ops->configure == NULL ||
 147             ops->compare == NULL || ops->fill == NULL ||
 148             ops->action == NULL)
 149                 return -EINVAL;
 150
 151         spin_lock(&net->rules_mod_lock);
 152         list_for_each_entry(o, &net->rules_ops, list)
 153                 if (ops->family == o->family)
 154                         goto errout;
 155
 156         list_add_tail_rcu(&ops->list, &net->rules_ops);
 157         err = 0;
 158 errout:
 159         spin_unlock(&net->rules_mod_lock);
 160
 161         return err;
 162 }
 163
 164 struct fib_rules_ops *
 165 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
 166 {
 167         struct fib_rules_ops *ops;
 168         int err;
 169
 170         ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
 171         if (ops == NULL)
 172                 return ERR_PTR(-ENOMEM);
 173
 174         INIT_LIST_HEAD(&ops->rules_list);
 175         ops->fro_net = net;
 176
 177         err = __fib_rules_register(ops);
 178         if (err) {
 179                 kfree(ops);
 180                 ops = ERR_PTR(err);
 181         }
 182
 183         return ops;
 184 }
 185 EXPORT_SYMBOL_GPL(fib_rules_register);
 186
 187 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
 188 {
 189         struct fib_rule *rule, *tmp;
 190
 191         list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
 192                 list_del_rcu(&rule->list);
 193                 if (ops->delete)
 194                         ops->delete(rule);
 195                 fib_rule_put(rule);
 196         }
 197 }
 198
 199 void fib_rules_unregister(struct fib_rules_ops *ops)
 200 {
 201         struct net *net = ops->fro_net;
 202
 203         spin_lock(&net->rules_mod_lock);
 204         list_del_rcu(&ops->list);
 205         spin_unlock(&net->rules_mod_lock);
 206
 207         fib_rules_cleanup_ops(ops);
 208         kfree_rcu(ops, rcu);
 209 }
 210 EXPORT_SYMBOL_GPL(fib_rules_unregister);
 211
 212 static int uid_range_set(struct fib_kuid_range *range)
 213 {
 214         return uid_valid(range->start) && uid_valid(range->end);
 215 }
 216
 217 static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb)
 218 {
 219         struct fib_rule_uid_range *in;
 220         struct fib_kuid_range out;
 221
 222         in = (struct fib_rule_uid_range *)nla_data(tb[FRA_UID_RANGE]);
 223
 224         out.start = make_kuid(current_user_ns(), in->start);
 225         out.end = make_kuid(current_user_ns(), in->end);
 226
 227         return out;
 228 }
 229
 230 static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range)
 231 {
 232         struct fib_rule_uid_range out = {
 233                 from_kuid_munged(current_user_ns(), range->start),
 234                 from_kuid_munged(current_user_ns(), range->end)
 235         };
 236
 237         return nla_put(skb, FRA_UID_RANGE, sizeof(out), &out);
 238 }
 239
 240 static int nla_get_port_range(struct nlattr *pattr,
 241                               struct fib_rule_port_range *port_range)
 242 {
 243         const struct fib_rule_port_range *pr = nla_data(pattr);
 244
 245         if (!fib_rule_port_range_valid(pr))
 246                 return -EINVAL;
 247
 248         port_range->start = pr->start;
 249         port_range->end = pr->end;
 250
 251         return 0;
 252 }
 253
 254 static int nla_put_port_range(struct sk_buff *skb, int attrtype,
 255                               struct fib_rule_port_range *range)
 256 {
 257         return nla_put(skb, attrtype, sizeof(*range), range);
 258 }
 259
 260 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
 261                           struct flowi *fl, int flags,
 262                           struct fib_lookup_arg *arg)
 263 {
 264         int ret = 0;
 265
 266         if (rule->iifindex && (rule->iifindex != fl->flowi_iif))
 267                 goto out;
 268
 269         if (rule->oifindex && (rule->oifindex != fl->flowi_oif))
 270                 goto out;
 271
 272         if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
 273                 goto out;
 274
 275         if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id))
 276                 goto out;
 277
 278         if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg))
 279                 goto out;
 280
 281         if (uid_lt(fl->flowi_uid, rule->uid_range.start) ||
 282             uid_gt(fl->flowi_uid, rule->uid_range.end))
 283                 goto out;
 284
 285         ret = INDIRECT_CALL_MT(ops->match,
 286                                fib6_rule_match,
 287                                fib4_rule_match,
 288                                rule, fl, flags);
 289 out:
 290         return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
 291 }
 292
 293 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
 294                      int flags, struct fib_lookup_arg *arg)
 295 {
 296         struct fib_rule *rule;
 297         int err;
 298
 299         rcu_read_lock();
 300
 301         list_for_each_entry_rcu(rule, &ops->rules_list, list) {
 302 jumped:
 303                 if (!fib_rule_match(rule, ops, fl, flags, arg))
 304                         continue;
 305
 306                 if (rule->action == FR_ACT_GOTO) {
 307                         struct fib_rule *target;
 308
 309                         target = rcu_dereference(rule->ctarget);
 310                         if (target == NULL) {
 311                                 continue;
 312                         } else {
 313                                 rule = target;
 314                                 goto jumped;
 315                         }
 316                 } else if (rule->action == FR_ACT_NOP)
 317                         continue;
 318                 else
 319                         err = INDIRECT_CALL_MT(ops->action,
 320                                                fib6_rule_action,
 321                                                fib4_rule_action,
 322                                                rule, fl, flags, arg);
 323
 324                 if (!err && ops->suppress && INDIRECT_CALL_MT(ops->suppress,
 325                                                               fib6_rule_suppress,
 326                                                               fib4_rule_suppress,
 327                                                               rule, flags, arg))
 328                         continue;
 329
 330                 if (err != -EAGAIN) {
 331                         if ((arg->flags & FIB_LOOKUP_NOREF) ||
 332                             likely(refcount_inc_not_zero(&rule->refcnt))) {
 333                                 arg->rule = rule;
 334                                 goto out;
 335                         }
 336                         break;
 337                 }
 338         }
 339
 340         err = -ESRCH;
 341 out:
 342         rcu_read_unlock();
 343
 344         return err;
 345 }
 346 EXPORT_SYMBOL_GPL(fib_rules_lookup);
 347
 348 static int call_fib_rule_notifier(struct notifier_block *nb,
 349                                   enum fib_event_type event_type,
 350                                   struct fib_rule *rule, int family,
 351                                   struct netlink_ext_ack *extack)
 352 {
 353         struct fib_rule_notifier_info info = {
 354                 .info.family = family,
 355                 .info.extack = extack,
 356                 .rule = rule,
 357         };
 358
 359         return call_fib_notifier(nb, event_type, &info.info);
 360 }
 361
 362 static int call_fib_rule_notifiers(struct net *net,
 363                                    enum fib_event_type event_type,
 364                                    struct fib_rule *rule,
 365                                    struct fib_rules_ops *ops,
 366                                    struct netlink_ext_ack *extack)
 367 {
 368         struct fib_rule_notifier_info info = {
 369                 .info.family = ops->family,
 370                 .info.extack = extack,
 371                 .rule = rule,
 372         };
 373
 374         ASSERT_RTNL();
 375         /* Paired with READ_ONCE() in fib_rules_seq() */
 376         WRITE_ONCE(ops->fib_rules_seq, ops->fib_rules_seq + 1);
 377         return call_fib_notifiers(net, event_type, &info.info);
 378 }
 379
 380 /* Called with rcu_read_lock() */
 381 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
 382                    struct netlink_ext_ack *extack)
 383 {
 384         struct fib_rules_ops *ops;
 385         struct fib_rule *rule;
 386         int err = 0;
 387
 388         ops = lookup_rules_ops(net, family);
 389         if (!ops)
 390                 return -EAFNOSUPPORT;
 391         list_for_each_entry_rcu(rule, &ops->rules_list, list) {
 392                 err = call_fib_rule_notifier(nb, FIB_EVENT_RULE_ADD,
 393                                              rule, family, extack);
 394                 if (err)
 395                         break;
 396         }
 397         rules_ops_put(ops);
 398
 399         return err;
 400 }
 401 EXPORT_SYMBOL_GPL(fib_rules_dump);
 402
 403 unsigned int fib_rules_seq_read(const struct net *net, int family)
 404 {
 405         unsigned int fib_rules_seq;
 406         struct fib_rules_ops *ops;
 407
 408         ops = lookup_rules_ops(net, family);
 409         if (!ops)
 410                 return 0;
 411         /* Paired with WRITE_ONCE() in call_fib_rule_notifiers() */
 412         fib_rules_seq = READ_ONCE(ops->fib_rules_seq);
 413         rules_ops_put(ops);
 414
 415         return fib_rules_seq;
 416 }
 417 EXPORT_SYMBOL_GPL(fib_rules_seq_read);
 418
 419 static struct fib_rule *rule_find(struct fib_rules_ops *ops,
 420                                   struct fib_rule_hdr *frh,
 421                                   struct nlattr **tb,
 422                                   struct fib_rule *rule,
 423                                   bool user_priority)
 424 {
 425         struct fib_rule *r;
 426
 427         list_for_each_entry(r, &ops->rules_list, list) {
 428                 if (rule->action && r->action != rule->action)
 429                         continue;
 430
 431                 if (rule->table && r->table != rule->table)
 432                         continue;
 433
 434                 if (user_priority && r->pref != rule->pref)
 435                         continue;
 436
 437                 if (rule->iifname[0] &&
 438                     memcmp(r->iifname, rule->iifname, IFNAMSIZ))
 439                         continue;
 440
 441                 if (rule->oifname[0] &&
 442                     memcmp(r->oifname, rule->oifname, IFNAMSIZ))
 443                         continue;
 444
 445                 if (rule->mark && r->mark != rule->mark)
 446                         continue;
 447
 448                 if (rule->suppress_ifgroup != -1 &&
 449                     r->suppress_ifgroup != rule->suppress_ifgroup)
 450                         continue;
 451
 452                 if (rule->suppress_prefixlen != -1 &&
 453                     r->suppress_prefixlen != rule->suppress_prefixlen)
 454                         continue;
 455
 456                 if (rule->mark_mask && r->mark_mask != rule->mark_mask)
 457                         continue;
 458
 459                 if (rule->tun_id && r->tun_id != rule->tun_id)
 460                         continue;
 461
 462                 if (r->fr_net != rule->fr_net)
 463                         continue;
 464
 465                 if (rule->l3mdev && r->l3mdev != rule->l3mdev)
 466                         continue;
 467
 468                 if (uid_range_set(&rule->uid_range) &&
 469                     (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
 470                     !uid_eq(r->uid_range.end, rule->uid_range.end)))
 471                         continue;
 472
 473                 if (rule->ip_proto && r->ip_proto != rule->ip_proto)
 474                         continue;
 475
 476                 if (rule->proto && r->proto != rule->proto)
 477                         continue;
 478
 479                 if (fib_rule_port_range_set(&rule->sport_range) &&
 480                     !fib_rule_port_range_compare(&r->sport_range,
 481                                                  &rule->sport_range))
 482                         continue;
 483
 484                 if (fib_rule_port_range_set(&rule->dport_range) &&
 485                     !fib_rule_port_range_compare(&r->dport_range,
 486                                                  &rule->dport_range))
 487                         continue;
 488
 489                 if (!ops->compare(r, frh, tb))
 490                         continue;
 491                 return r;
 492         }
 493
 494         return NULL;
 495 }
 496
 497 #ifdef CONFIG_NET_L3_MASTER_DEV
 498 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
 499                               struct netlink_ext_ack *extack)
 500 {
 501         nlrule->l3mdev = nla_get_u8(nla);
 502         if (nlrule->l3mdev != 1) {
 503                 NL_SET_ERR_MSG(extack, "Invalid l3mdev attribute");
 504                 return -1;
 505         }
 506
 507         return 0;
 508 }
 509 #else
 510 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
 511                               struct netlink_ext_ack *extack)
 512 {
 513         NL_SET_ERR_MSG(extack, "l3mdev support is not enabled in kernel");
 514         return -1;
 515 }
 516 #endif
 517
 518 static int fib_nl2rule(struct sk_buff *skb, struct nlmsghdr *nlh,
 519                        struct netlink_ext_ack *extack,
 520                        struct fib_rules_ops *ops,
 521                        struct nlattr *tb[],
 522                        struct fib_rule **rule,
 523                        bool *user_priority)
 524 {
 525         struct net *net = sock_net(skb->sk);
 526         struct fib_rule_hdr *frh = nlmsg_data(nlh);
 527         struct fib_rule *nlrule = NULL;
 528         int err = -EINVAL;
 529
 530         if (frh->src_len)
 531                 if (!tb[FRA_SRC] ||
 532                     frh->src_len > (ops->addr_size * 8) ||
 533                     nla_len(tb[FRA_SRC]) != ops->addr_size) {
 534                         NL_SET_ERR_MSG(extack, "Invalid source address");
 535                         goto errout;
 536         }
 537
 538         if (frh->dst_len)
 539                 if (!tb[FRA_DST] ||
 540                     frh->dst_len > (ops->addr_size * 8) ||
 541                     nla_len(tb[FRA_DST]) != ops->addr_size) {
 542                         NL_SET_ERR_MSG(extack, "Invalid dst address");
 543                         goto errout;
 544         }
 545
 546         nlrule = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT);
 547         if (!nlrule) {
 548                 err = -ENOMEM;
 549                 goto errout;
 550         }
 551         refcount_set(&nlrule->refcnt, 1);
 552         nlrule->fr_net = net;
 553
 554         if (tb[FRA_PRIORITY]) {
 555                 nlrule->pref = nla_get_u32(tb[FRA_PRIORITY]);
 556                 *user_priority = true;
 557         } else {
 558                 nlrule->pref = fib_default_rule_pref(ops);
 559         }
 560
 561         nlrule->proto = nla_get_u8_default(tb[FRA_PROTOCOL], RTPROT_UNSPEC);
 562
 563         if (tb[FRA_IIFNAME]) {
 564                 struct net_device *dev;
 565
 566                 nlrule->iifindex = -1;
 567                 nla_strscpy(nlrule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
 568                 dev = __dev_get_by_name(net, nlrule->iifname);
 569                 if (dev)
 570                         nlrule->iifindex = dev->ifindex;
 571         }
 572
 573         if (tb[FRA_OIFNAME]) {
 574                 struct net_device *dev;
 575
 576                 nlrule->oifindex = -1;
 577                 nla_strscpy(nlrule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
 578                 dev = __dev_get_by_name(net, nlrule->oifname);
 579                 if (dev)
 580                         nlrule->oifindex = dev->ifindex;
 581         }
 582
 583         if (tb[FRA_FWMARK]) {
 584                 nlrule->mark = nla_get_u32(tb[FRA_FWMARK]);
 585                 if (nlrule->mark)
 586                         /* compatibility: if the mark value is non-zero all bits
 587                          * are compared unless a mask is explicitly specified.
 588                          */
 589                         nlrule->mark_mask = 0xFFFFFFFF;
 590         }
 591
 592         if (tb[FRA_FWMASK])
 593                 nlrule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
 594
 595         if (tb[FRA_TUN_ID])
 596                 nlrule->tun_id = nla_get_be64(tb[FRA_TUN_ID]);
 597
 598         if (tb[FRA_L3MDEV] &&
 599             fib_nl2rule_l3mdev(tb[FRA_L3MDEV], nlrule, extack) < 0)
 600                 goto errout_free;
 601
 602         nlrule->action = frh->action;
 603         nlrule->flags = frh->flags;
 604         nlrule->table = frh_get_table(frh, tb);
 605         if (tb[FRA_SUPPRESS_PREFIXLEN])
 606                 nlrule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]);
 607         else
 608                 nlrule->suppress_prefixlen = -1;
 609
 610         if (tb[FRA_SUPPRESS_IFGROUP])
 611                 nlrule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]);
 612         else
 613                 nlrule->suppress_ifgroup = -1;
 614
 615         if (tb[FRA_GOTO]) {
 616                 if (nlrule->action != FR_ACT_GOTO) {
 617                         NL_SET_ERR_MSG(extack, "Unexpected goto");
 618                         goto errout_free;
 619                 }
 620
 621                 nlrule->target = nla_get_u32(tb[FRA_GOTO]);
 622                 /* Backward jumps are prohibited to avoid endless loops */
 623                 if (nlrule->target <= nlrule->pref) {
 624                         NL_SET_ERR_MSG(extack, "Backward goto not supported");
 625                         goto errout_free;
 626                 }
 627         } else if (nlrule->action == FR_ACT_GOTO) {
 628                 NL_SET_ERR_MSG(extack, "Missing goto target for action goto");
 629                 goto errout_free;
 630         }
 631
 632         if (nlrule->l3mdev && nlrule->table) {
 633                 NL_SET_ERR_MSG(extack, "l3mdev and table are mutually exclusive");
 634                 goto errout_free;
 635         }
 636
 637         if (tb[FRA_UID_RANGE]) {
 638                 if (current_user_ns() != net->user_ns) {
 639                         err = -EPERM;
 640                         NL_SET_ERR_MSG(extack, "No permission to set uid");
 641                         goto errout_free;
 642                 }
 643
 644                 nlrule->uid_range = nla_get_kuid_range(tb);
 645
 646                 if (!uid_range_set(&nlrule->uid_range) ||
 647                     !uid_lte(nlrule->uid_range.start, nlrule->uid_range.end)) {
 648                         NL_SET_ERR_MSG(extack, "Invalid uid range");
 649                         goto errout_free;
 650                 }
 651         } else {
 652                 nlrule->uid_range = fib_kuid_range_unset;
 653         }
 654
 655         if (tb[FRA_IP_PROTO])
 656                 nlrule->ip_proto = nla_get_u8(tb[FRA_IP_PROTO]);
 657
 658         if (tb[FRA_SPORT_RANGE]) {
 659                 err = nla_get_port_range(tb[FRA_SPORT_RANGE],
 660                                          &nlrule->sport_range);
 661                 if (err) {
 662                         NL_SET_ERR_MSG(extack, "Invalid sport range");
 663                         goto errout_free;
 664                 }
 665         }
 666
 667         if (tb[FRA_DPORT_RANGE]) {
 668                 err = nla_get_port_range(tb[FRA_DPORT_RANGE],
 669                                          &nlrule->dport_range);
 670                 if (err) {
 671                         NL_SET_ERR_MSG(extack, "Invalid dport range");
 672                         goto errout_free;
 673                 }
 674         }
 675
 676         *rule = nlrule;
 677
 678         return 0;
 679
 680 errout_free:
 681         kfree(nlrule);
 682 errout:
 683         return err;
 684 }
 685
 686 static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh,
 687                        struct nlattr **tb, struct fib_rule *rule)
 688 {
 689         struct fib_rule *r;
 690
 691         list_for_each_entry(r, &ops->rules_list, list) {
 692                 if (r->action != rule->action)
 693                         continue;
 694
 695                 if (r->table != rule->table)
 696                         continue;
 697
 698                 if (r->pref != rule->pref)
 699                         continue;
 700
 701                 if (memcmp(r->iifname, rule->iifname, IFNAMSIZ))
 702                         continue;
 703
 704                 if (memcmp(r->oifname, rule->oifname, IFNAMSIZ))
 705                         continue;
 706
 707                 if (r->mark != rule->mark)
 708                         continue;
 709
 710                 if (r->suppress_ifgroup != rule->suppress_ifgroup)
 711                         continue;
 712
 713                 if (r->suppress_prefixlen != rule->suppress_prefixlen)
 714                         continue;
 715
 716                 if (r->mark_mask != rule->mark_mask)
 717                         continue;
 718
 719                 if (r->tun_id != rule->tun_id)
 720                         continue;
 721
 722                 if (r->fr_net != rule->fr_net)
 723                         continue;
 724
 725                 if (r->l3mdev != rule->l3mdev)
 726                         continue;
 727
 728                 if (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
 729                     !uid_eq(r->uid_range.end, rule->uid_range.end))
 730                         continue;
 731
 732                 if (r->ip_proto != rule->ip_proto)
 733                         continue;
 734
 735                 if (r->proto != rule->proto)
 736                         continue;
 737
 738                 if (!fib_rule_port_range_compare(&r->sport_range,
 739                                                  &rule->sport_range))
 740                         continue;
 741
 742                 if (!fib_rule_port_range_compare(&r->dport_range,
 743                                                  &rule->dport_range))
 744                         continue;
 745
 746                 if (!ops->compare(r, frh, tb))
 747                         continue;
 748                 return 1;
 749         }
 750         return 0;
 751 }
 752
 753 static const struct nla_policy fib_rule_policy[FRA_MAX + 1] = {
 754         [FRA_UNSPEC]    = { .strict_start_type = FRA_DPORT_RANGE + 1 },
 755         [FRA_IIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
 756         [FRA_OIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
 757         [FRA_PRIORITY]  = { .type = NLA_U32 },
 758         [FRA_FWMARK]    = { .type = NLA_U32 },
 759         [FRA_FLOW]      = { .type = NLA_U32 },
 760         [FRA_TUN_ID]    = { .type = NLA_U64 },
 761         [FRA_FWMASK]    = { .type = NLA_U32 },
 762         [FRA_TABLE]     = { .type = NLA_U32 },
 763         [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 },
 764         [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 },
 765         [FRA_GOTO]      = { .type = NLA_U32 },
 766         [FRA_L3MDEV]    = { .type = NLA_U8 },
 767         [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) },
 768         [FRA_PROTOCOL]  = { .type = NLA_U8 },
 769         [FRA_IP_PROTO]  = { .type = NLA_U8 },
 770         [FRA_SPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
 771         [FRA_DPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
 772         [FRA_DSCP]      = NLA_POLICY_MAX(NLA_U8, INET_DSCP_MASK >> 2),
 773 };
 774
 775 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 776                    struct netlink_ext_ack *extack)
 777 {
 778         struct net *net = sock_net(skb->sk);
 779         struct fib_rule_hdr *frh = nlmsg_data(nlh);
 780         struct fib_rules_ops *ops = NULL;
 781         struct fib_rule *rule = NULL, *r, *last = NULL;
 782         struct nlattr *tb[FRA_MAX + 1];
 783         int err = -EINVAL, unresolved = 0;
 784         bool user_priority = false;
 785
 786         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
 787                 NL_SET_ERR_MSG(extack, "Invalid msg length");
 788                 goto errout;
 789         }
 790
 791         ops = lookup_rules_ops(net, frh->family);
 792         if (!ops) {
 793                 err = -EAFNOSUPPORT;
 794                 NL_SET_ERR_MSG(extack, "Rule family not supported");
 795                 goto errout;
 796         }
 797
 798         err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
 799                                      fib_rule_policy, extack);
 800         if (err < 0) {
 801                 NL_SET_ERR_MSG(extack, "Error parsing msg");
 802                 goto errout;
 803         }
 804
 805         err = fib_nl2rule(skb, nlh, extack, ops, tb, &rule, &user_priority);
 806         if (err)
 807                 goto errout;
 808
 809         if ((nlh->nlmsg_flags & NLM_F_EXCL) &&
 810             rule_exists(ops, frh, tb, rule)) {
 811                 err = -EEXIST;
 812                 goto errout_free;
 813         }
 814
 815         err = ops->configure(rule, skb, frh, tb, extack);
 816         if (err < 0)
 817                 goto errout_free;
 818
 819         err = call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule, ops,
 820                                       extack);
 821         if (err < 0)
 822                 goto errout_free;
 823
 824         list_for_each_entry(r, &ops->rules_list, list) {
 825                 if (r->pref == rule->target) {
 826                         RCU_INIT_POINTER(rule->ctarget, r);
 827                         break;
 828                 }
 829         }
 830
 831         if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
 832                 unresolved = 1;
 833
 834         list_for_each_entry(r, &ops->rules_list, list) {
 835                 if (r->pref > rule->pref)
 836                         break;
 837                 last = r;
 838         }
 839
 840         if (last)
 841                 list_add_rcu(&rule->list, &last->list);
 842         else
 843                 list_add_rcu(&rule->list, &ops->rules_list);
 844
 845         if (ops->unresolved_rules) {
 846                 /*
 847                  * There are unresolved goto rules in the list, check if
 848                  * any of them are pointing to this new rule.
 849                  */
 850                 list_for_each_entry(r, &ops->rules_list, list) {
 851                         if (r->action == FR_ACT_GOTO &&
 852                             r->target == rule->pref &&
 853                             rtnl_dereference(r->ctarget) == NULL) {
 854                                 rcu_assign_pointer(r->ctarget, rule);
 855                                 if (--ops->unresolved_rules == 0)
 856                                         break;
 857                         }
 858                 }
 859         }
 860
 861         if (rule->action == FR_ACT_GOTO)
 862                 ops->nr_goto_rules++;
 863
 864         if (unresolved)
 865                 ops->unresolved_rules++;
 866
 867         if (rule->tun_id)
 868                 ip_tunnel_need_metadata();
 869
 870         notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
 871         flush_route_cache(ops);
 872         rules_ops_put(ops);
 873         return 0;
 874
 875 errout_free:
 876         kfree(rule);
 877 errout:
 878         rules_ops_put(ops);
 879         return err;
 880 }
 881 EXPORT_SYMBOL_GPL(fib_nl_newrule);
 882
 883 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 884                    struct netlink_ext_ack *extack)
 885 {
 886         struct net *net = sock_net(skb->sk);
 887         struct fib_rule_hdr *frh = nlmsg_data(nlh);
 888         struct fib_rules_ops *ops = NULL;
 889         struct fib_rule *rule = NULL, *r, *nlrule = NULL;
 890         struct nlattr *tb[FRA_MAX+1];
 891         int err = -EINVAL;
 892         bool user_priority = false;
 893
 894         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
 895                 NL_SET_ERR_MSG(extack, "Invalid msg length");
 896                 goto errout;
 897         }
 898
 899         ops = lookup_rules_ops(net, frh->family);
 900         if (ops == NULL) {
 901                 err = -EAFNOSUPPORT;
 902                 NL_SET_ERR_MSG(extack, "Rule family not supported");
 903                 goto errout;
 904         }
 905
 906         err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
 907                                      fib_rule_policy, extack);
 908         if (err < 0) {
 909                 NL_SET_ERR_MSG(extack, "Error parsing msg");
 910                 goto errout;
 911         }
 912
 913         err = fib_nl2rule(skb, nlh, extack, ops, tb, &nlrule, &user_priority);
 914         if (err)
 915                 goto errout;
 916
 917         rule = rule_find(ops, frh, tb, nlrule, user_priority);
 918         if (!rule) {
 919                 err = -ENOENT;
 920                 goto errout;
 921         }
 922
 923         if (rule->flags & FIB_RULE_PERMANENT) {
 924                 err = -EPERM;
 925                 goto errout;
 926         }
 927
 928         if (ops->delete) {
 929                 err = ops->delete(rule);
 930                 if (err)
 931                         goto errout;
 932         }
 933
 934         if (rule->tun_id)
 935                 ip_tunnel_unneed_metadata();
 936
 937         list_del_rcu(&rule->list);
 938
 939         if (rule->action == FR_ACT_GOTO) {
 940                 ops->nr_goto_rules--;
 941                 if (rtnl_dereference(rule->ctarget) == NULL)
 942                         ops->unresolved_rules--;
 943         }
 944
 945         /*
 946          * Check if this rule is a target to any of them. If so,
 947          * adjust to the next one with the same preference or
 948          * disable them. As this operation is eventually very
 949          * expensive, it is only performed if goto rules, except
 950          * current if it is goto rule, have actually been added.
 951          */
 952         if (ops->nr_goto_rules > 0) {
 953                 struct fib_rule *n;
 954
 955                 n = list_next_entry(rule, list);
 956                 if (&n->list == &ops->rules_list || n->pref != rule->pref)
 957                         n = NULL;
 958                 list_for_each_entry(r, &ops->rules_list, list) {
 959                         if (rtnl_dereference(r->ctarget) != rule)
 960                                 continue;
 961                         rcu_assign_pointer(r->ctarget, n);
 962                         if (!n)
 963                                 ops->unresolved_rules++;
 964                 }
 965         }
 966
 967         call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule, ops,
 968                                 NULL);
 969         notify_rule_change(RTM_DELRULE, rule, ops, nlh,
 970                            NETLINK_CB(skb).portid);
 971         fib_rule_put(rule);
 972         flush_route_cache(ops);
 973         rules_ops_put(ops);
 974         kfree(nlrule);
 975         return 0;
 976
 977 errout:
 978         kfree(nlrule);
 979         rules_ops_put(ops);
 980         return err;
 981 }
 982 EXPORT_SYMBOL_GPL(fib_nl_delrule);
 983
 984 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
 985                                          struct fib_rule *rule)
 986 {
 987         size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
 988                          + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
 989                          + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
 990                          + nla_total_size(4) /* FRA_PRIORITY */
 991                          + nla_total_size(4) /* FRA_TABLE */
 992                          + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */
 993                          + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */
 994                          + nla_total_size(4) /* FRA_FWMARK */
 995                          + nla_total_size(4) /* FRA_FWMASK */
 996                          + nla_total_size_64bit(8) /* FRA_TUN_ID */
 997                          + nla_total_size(sizeof(struct fib_kuid_range))
 998                          + nla_total_size(1) /* FRA_PROTOCOL */
 999                          + nla_total_size(1) /* FRA_IP_PROTO */
1000                          + nla_total_size(sizeof(struct fib_rule_port_range)) /* FRA_SPORT_RANGE */
1001                          + nla_total_size(sizeof(struct fib_rule_port_range)); /* FRA_DPORT_RANGE */
1002
1003         if (ops->nlmsg_payload)
1004                 payload += ops->nlmsg_payload(rule);
1005
1006         return payload;
1007 }
1008
1009 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
1010                             u32 pid, u32 seq, int type, int flags,
1011                             struct fib_rules_ops *ops)
1012 {
1013         struct nlmsghdr *nlh;
1014         struct fib_rule_hdr *frh;
1015
1016         nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
1017         if (nlh == NULL)
1018                 return -EMSGSIZE;
1019
1020         frh = nlmsg_data(nlh);
1021         frh->family = ops->family;
1022         frh->table = rule->table < 256 ? rule->table : RT_TABLE_COMPAT;
1023         if (nla_put_u32(skb, FRA_TABLE, rule->table))
1024                 goto nla_put_failure;
1025         if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen))
1026                 goto nla_put_failure;
1027         frh->res1 = 0;
1028         frh->res2 = 0;
1029         frh->action = rule->action;
1030         frh->flags = rule->flags;
1031
1032         if (nla_put_u8(skb, FRA_PROTOCOL, rule->proto))
1033                 goto nla_put_failure;
1034
1035         if (rule->action == FR_ACT_GOTO &&
1036             rcu_access_pointer(rule->ctarget) == NULL)
1037                 frh->flags |= FIB_RULE_UNRESOLVED;
1038
1039         if (rule->iifname[0]) {
1040                 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname))
1041                         goto nla_put_failure;
1042                 if (rule->iifindex == -1)
1043                         frh->flags |= FIB_RULE_IIF_DETACHED;
1044         }
1045
1046         if (rule->oifname[0]) {
1047                 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname))
1048                         goto nla_put_failure;
1049                 if (rule->oifindex == -1)
1050                         frh->flags |= FIB_RULE_OIF_DETACHED;
1051         }
1052
1053         if ((rule->pref &&
1054              nla_put_u32(skb, FRA_PRIORITY, rule->pref)) ||
1055             (rule->mark &&
1056              nla_put_u32(skb, FRA_FWMARK, rule->mark)) ||
1057             ((rule->mark_mask || rule->mark) &&
1058              nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) ||
1059             (rule->target &&
1060              nla_put_u32(skb, FRA_GOTO, rule->target)) ||
1061             (rule->tun_id &&
1062              nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) ||
1063             (rule->l3mdev &&
1064              nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)) ||
1065             (uid_range_set(&rule->uid_range) &&
1066              nla_put_uid_range(skb, &rule->uid_range)) ||
1067             (fib_rule_port_range_set(&rule->sport_range) &&
1068              nla_put_port_range(skb, FRA_SPORT_RANGE, &rule->sport_range)) ||
1069             (fib_rule_port_range_set(&rule->dport_range) &&
1070              nla_put_port_range(skb, FRA_DPORT_RANGE, &rule->dport_range)) ||
1071             (rule->ip_proto && nla_put_u8(skb, FRA_IP_PROTO, rule->ip_proto)))
1072                 goto nla_put_failure;
1073
1074         if (rule->suppress_ifgroup != -1) {
1075                 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup))
1076                         goto nla_put_failure;
1077         }
1078
1079         if (ops->fill(rule, skb, frh) < 0)
1080                 goto nla_put_failure;
1081
1082         nlmsg_end(skb, nlh);
1083         return 0;
1084
1085 nla_put_failure:
1086         nlmsg_cancel(skb, nlh);
1087         return -EMSGSIZE;
1088 }
1089
1090 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
1091                       struct fib_rules_ops *ops)
1092 {
1093         int idx = 0;
1094         struct fib_rule *rule;
1095         int err = 0;
1096
1097         rcu_read_lock();
1098         list_for_each_entry_rcu(rule, &ops->rules_list, list) {
1099                 if (idx < cb->args[1])
1100                         goto skip;
1101
1102                 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
1103                                        cb->nlh->nlmsg_seq, RTM_NEWRULE,
1104                                        NLM_F_MULTI, ops);
1105                 if (err)
1106                         break;
1107 skip:
1108                 idx++;
1109         }
1110         rcu_read_unlock();
1111         cb->args[1] = idx;
1112         rules_ops_put(ops);
1113
1114         return err;
1115 }
1116
1117 static int fib_valid_dumprule_req(const struct nlmsghdr *nlh,
1118                                    struct netlink_ext_ack *extack)
1119 {
1120         struct fib_rule_hdr *frh;
1121
1122         if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
1123                 NL_SET_ERR_MSG(extack, "Invalid header for fib rule dump request");
1124                 return -EINVAL;
1125         }
1126
1127         frh = nlmsg_data(nlh);
1128         if (frh->dst_len || frh->src_len || frh->tos || frh->table ||
1129             frh->res1 || frh->res2 || frh->action || frh->flags) {
1130                 NL_SET_ERR_MSG(extack,
1131                                "Invalid values in header for fib rule dump request");
1132                 return -EINVAL;
1133         }
1134
1135         if (nlmsg_attrlen(nlh, sizeof(*frh))) {
1136                 NL_SET_ERR_MSG(extack, "Invalid data after header in fib rule dump request");
1137                 return -EINVAL;
1138         }
1139
1140         return 0;
1141 }
1142
1143 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
1144 {
1145         const struct nlmsghdr *nlh = cb->nlh;
1146         struct net *net = sock_net(skb->sk);
1147         struct fib_rules_ops *ops;
1148         int err, idx = 0, family;
1149
1150         if (cb->strict_check) {
1151                 err = fib_valid_dumprule_req(nlh, cb->extack);
1152
1153                 if (err < 0)
1154                         return err;
1155         }
1156
1157         family = rtnl_msg_family(nlh);
1158         if (family != AF_UNSPEC) {
1159                 /* Protocol specific dump request */
1160                 ops = lookup_rules_ops(net, family);
1161                 if (ops == NULL)
1162                         return -EAFNOSUPPORT;
1163
1164                 return dump_rules(skb, cb, ops);
1165         }
1166
1167         err = 0;
1168         rcu_read_lock();
1169         list_for_each_entry_rcu(ops, &net->rules_ops, list) {
1170                 if (idx < cb->args[0] || !try_module_get(ops->owner))
1171                         goto skip;
1172
1173                 err = dump_rules(skb, cb, ops);
1174                 if (err < 0)
1175                         break;
1176
1177                 cb->args[1] = 0;
1178 skip:
1179                 idx++;
1180         }
1181         rcu_read_unlock();
1182         cb->args[0] = idx;
1183
1184         return err;
1185 }
1186
1187 static void notify_rule_change(int event, struct fib_rule *rule,
1188                                struct fib_rules_ops *ops, struct nlmsghdr *nlh,
1189                                u32 pid)
1190 {
1191         struct net *net;
1192         struct sk_buff *skb;
1193         int err = -ENOMEM;
1194
1195         net = ops->fro_net;
1196         skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
1197         if (skb == NULL)
1198                 goto errout;
1199
1200         err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
1201         if (err < 0) {
1202                 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
1203                 WARN_ON(err == -EMSGSIZE);
1204                 kfree_skb(skb);
1205                 goto errout;
1206         }
1207
1208         rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
1209         return;
1210 errout:
1211         rtnl_set_sk_err(net, ops->nlgroup, err);
1212 }
1213
1214 static void attach_rules(struct list_head *rules, struct net_device *dev)
1215 {
1216         struct fib_rule *rule;
1217
1218         list_for_each_entry(rule, rules, list) {
1219                 if (rule->iifindex == -1 &&
1220                     strcmp(dev->name, rule->iifname) == 0)
1221                         rule->iifindex = dev->ifindex;
1222                 if (rule->oifindex == -1 &&
1223                     strcmp(dev->name, rule->oifname) == 0)
1224                         rule->oifindex = dev->ifindex;
1225         }
1226 }
1227
1228 static void detach_rules(struct list_head *rules, struct net_device *dev)
1229 {
1230         struct fib_rule *rule;
1231
1232         list_for_each_entry(rule, rules, list) {
1233                 if (rule->iifindex == dev->ifindex)
1234                         rule->iifindex = -1;
1235                 if (rule->oifindex == dev->ifindex)
1236                         rule->oifindex = -1;
1237         }
1238 }
1239
1240
1241 static int fib_rules_event(struct notifier_block *this, unsigned long event,
1242                            void *ptr)
1243 {
1244         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1245         struct net *net = dev_net(dev);
1246         struct fib_rules_ops *ops;
1247
1248         ASSERT_RTNL();
1249
1250         switch (event) {
1251         case NETDEV_REGISTER:
1252                 list_for_each_entry(ops, &net->rules_ops, list)
1253                         attach_rules(&ops->rules_list, dev);
1254                 break;
1255
1256         case NETDEV_CHANGENAME:
1257                 list_for_each_entry(ops, &net->rules_ops, list) {
1258                         detach_rules(&ops->rules_list, dev);
1259                         attach_rules(&ops->rules_list, dev);
1260                 }
1261                 break;
1262
1263         case NETDEV_UNREGISTER:
1264                 list_for_each_entry(ops, &net->rules_ops, list)
1265                         detach_rules(&ops->rules_list, dev);
1266                 break;
1267         }
1268
1269         return NOTIFY_DONE;
1270 }
1271
1272 static struct notifier_block fib_rules_notifier = {
1273         .notifier_call = fib_rules_event,
1274 };
1275
1276 static int __net_init fib_rules_net_init(struct net *net)
1277 {
1278         INIT_LIST_HEAD(&net->rules_ops);
1279         spin_lock_init(&net->rules_mod_lock);
1280         return 0;
1281 }
1282
1283 static void __net_exit fib_rules_net_exit(struct net *net)
1284 {
1285         WARN_ON_ONCE(!list_empty(&net->rules_ops));
1286 }
1287
1288 static struct pernet_operations fib_rules_net_ops = {
1289         .init = fib_rules_net_init,
1290         .exit = fib_rules_net_exit,
1291 };
1292
1293 static const struct rtnl_msg_handler fib_rules_rtnl_msg_handlers[] __initconst = {
1294         {.msgtype = RTM_NEWRULE, .doit = fib_nl_newrule},
1295         {.msgtype = RTM_DELRULE, .doit = fib_nl_delrule},
1296         {.msgtype = RTM_GETRULE, .dumpit = fib_nl_dumprule,
1297          .flags = RTNL_FLAG_DUMP_UNLOCKED},
1298 };
1299
1300 static int __init fib_rules_init(void)
1301 {
1302         int err;
1303
1304         rtnl_register_many(fib_rules_rtnl_msg_handlers);
1305
1306         err = register_pernet_subsys(&fib_rules_net_ops);
1307         if (err < 0)
1308                 goto fail;
1309
1310         err = register_netdevice_notifier(&fib_rules_notifier);
1311         if (err < 0)
1312                 goto fail_unregister;
1313
1314         return 0;
1315
1316 fail_unregister:
1317         unregister_pernet_subsys(&fib_rules_net_ops);
1318 fail:
1319         rtnl_unregister_many(fib_rules_rtnl_msg_handlers);
1320         return err;
1321 }
1322
1323 subsys_initcall(fib_rules_init);