linux/net/core/fib_rules.c
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   1/*
   2 * net/core/fib_rules.c         Generic Routing Rules
   3 *
   4 *      This program is free software; you can redistribute it and/or
   5 *      modify it under the terms of the GNU General Public License as
   6 *      published by the Free Software Foundation, version 2.
   7 *
   8 * Authors:     Thomas Graf <tgraf@suug.ch>
   9 */
  10
  11#include <linux/types.h>
  12#include <linux/kernel.h>
  13#include <linux/slab.h>
  14#include <linux/list.h>
  15#include <linux/module.h>
  16#include <net/net_namespace.h>
  17#include <net/sock.h>
  18#include <net/fib_rules.h>
  19
  20int fib_default_rule_add(struct fib_rules_ops *ops,
  21                         u32 pref, u32 table, u32 flags)
  22{
  23        struct fib_rule *r;
  24
  25        r = kzalloc(ops->rule_size, GFP_KERNEL);
  26        if (r == NULL)
  27                return -ENOMEM;
  28
  29        atomic_set(&r->refcnt, 1);
  30        r->action = FR_ACT_TO_TBL;
  31        r->pref = pref;
  32        r->table = table;
  33        r->flags = flags;
  34        r->fr_net = hold_net(ops->fro_net);
  35
  36        /* The lock is not required here, the list in unreacheable
  37         * at the moment this function is called */
  38        list_add_tail(&r->list, &ops->rules_list);
  39        return 0;
  40}
  41EXPORT_SYMBOL(fib_default_rule_add);
  42
  43u32 fib_default_rule_pref(struct fib_rules_ops *ops)
  44{
  45        struct list_head *pos;
  46        struct fib_rule *rule;
  47
  48        if (!list_empty(&ops->rules_list)) {
  49                pos = ops->rules_list.next;
  50                if (pos->next != &ops->rules_list) {
  51                        rule = list_entry(pos->next, struct fib_rule, list);
  52                        if (rule->pref)
  53                                return rule->pref - 1;
  54                }
  55        }
  56
  57        return 0;
  58}
  59EXPORT_SYMBOL(fib_default_rule_pref);
  60
  61static void notify_rule_change(int event, struct fib_rule *rule,
  62                               struct fib_rules_ops *ops, struct nlmsghdr *nlh,
  63                               u32 pid);
  64
  65static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
  66{
  67        struct fib_rules_ops *ops;
  68
  69        rcu_read_lock();
  70        list_for_each_entry_rcu(ops, &net->rules_ops, list) {
  71                if (ops->family == family) {
  72                        if (!try_module_get(ops->owner))
  73                                ops = NULL;
  74                        rcu_read_unlock();
  75                        return ops;
  76                }
  77        }
  78        rcu_read_unlock();
  79
  80        return NULL;
  81}
  82
  83static void rules_ops_put(struct fib_rules_ops *ops)
  84{
  85        if (ops)
  86                module_put(ops->owner);
  87}
  88
  89static void flush_route_cache(struct fib_rules_ops *ops)
  90{
  91        if (ops->flush_cache)
  92                ops->flush_cache(ops);
  93}
  94
  95static int __fib_rules_register(struct fib_rules_ops *ops)
  96{
  97        int err = -EEXIST;
  98        struct fib_rules_ops *o;
  99        struct net *net;
 100
 101        net = ops->fro_net;
 102
 103        if (ops->rule_size < sizeof(struct fib_rule))
 104                return -EINVAL;
 105
 106        if (ops->match == NULL || ops->configure == NULL ||
 107            ops->compare == NULL || ops->fill == NULL ||
 108            ops->action == NULL)
 109                return -EINVAL;
 110
 111        spin_lock(&net->rules_mod_lock);
 112        list_for_each_entry(o, &net->rules_ops, list)
 113                if (ops->family == o->family)
 114                        goto errout;
 115
 116        hold_net(net);
 117        list_add_tail_rcu(&ops->list, &net->rules_ops);
 118        err = 0;
 119errout:
 120        spin_unlock(&net->rules_mod_lock);
 121
 122        return err;
 123}
 124
 125struct fib_rules_ops *
 126fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
 127{
 128        struct fib_rules_ops *ops;
 129        int err;
 130
 131        ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
 132        if (ops == NULL)
 133                return ERR_PTR(-ENOMEM);
 134
 135        INIT_LIST_HEAD(&ops->rules_list);
 136        ops->fro_net = net;
 137
 138        err = __fib_rules_register(ops);
 139        if (err) {
 140                kfree(ops);
 141                ops = ERR_PTR(err);
 142        }
 143
 144        return ops;
 145}
 146EXPORT_SYMBOL_GPL(fib_rules_register);
 147
 148static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
 149{
 150        struct fib_rule *rule, *tmp;
 151
 152        list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
 153                list_del_rcu(&rule->list);
 154                if (ops->delete)
 155                        ops->delete(rule);
 156                fib_rule_put(rule);
 157        }
 158}
 159
 160static void fib_rules_put_rcu(struct rcu_head *head)
 161{
 162        struct fib_rules_ops *ops = container_of(head, struct fib_rules_ops, rcu);
 163        struct net *net = ops->fro_net;
 164
 165        release_net(net);
 166        kfree(ops);
 167}
 168
 169void fib_rules_unregister(struct fib_rules_ops *ops)
 170{
 171        struct net *net = ops->fro_net;
 172
 173        spin_lock(&net->rules_mod_lock);
 174        list_del_rcu(&ops->list);
 175        fib_rules_cleanup_ops(ops);
 176        spin_unlock(&net->rules_mod_lock);
 177
 178        call_rcu(&ops->rcu, fib_rules_put_rcu);
 179}
 180EXPORT_SYMBOL_GPL(fib_rules_unregister);
 181
 182static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
 183                          struct flowi *fl, int flags)
 184{
 185        int ret = 0;
 186
 187        if (rule->iifindex && (rule->iifindex != fl->flowi_iif))
 188                goto out;
 189
 190        if (rule->oifindex && (rule->oifindex != fl->flowi_oif))
 191                goto out;
 192
 193        if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
 194                goto out;
 195
 196        ret = ops->match(rule, fl, flags);
 197out:
 198        return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
 199}
 200
 201int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
 202                     int flags, struct fib_lookup_arg *arg)
 203{
 204        struct fib_rule *rule;
 205        int err;
 206
 207        rcu_read_lock();
 208
 209        list_for_each_entry_rcu(rule, &ops->rules_list, list) {
 210jumped:
 211                if (!fib_rule_match(rule, ops, fl, flags))
 212                        continue;
 213
 214                if (rule->action == FR_ACT_GOTO) {
 215                        struct fib_rule *target;
 216
 217                        target = rcu_dereference(rule->ctarget);
 218                        if (target == NULL) {
 219                                continue;
 220                        } else {
 221                                rule = target;
 222                                goto jumped;
 223                        }
 224                } else if (rule->action == FR_ACT_NOP)
 225                        continue;
 226                else
 227                        err = ops->action(rule, fl, flags, arg);
 228
 229                if (err != -EAGAIN) {
 230                        if ((arg->flags & FIB_LOOKUP_NOREF) ||
 231                            likely(atomic_inc_not_zero(&rule->refcnt))) {
 232                                arg->rule = rule;
 233                                goto out;
 234                        }
 235                        break;
 236                }
 237        }
 238
 239        err = -ESRCH;
 240out:
 241        rcu_read_unlock();
 242
 243        return err;
 244}
 245EXPORT_SYMBOL_GPL(fib_rules_lookup);
 246
 247static int validate_rulemsg(struct fib_rule_hdr *frh, struct nlattr **tb,
 248                            struct fib_rules_ops *ops)
 249{
 250        int err = -EINVAL;
 251
 252        if (frh->src_len)
 253                if (tb[FRA_SRC] == NULL ||
 254                    frh->src_len > (ops->addr_size * 8) ||
 255                    nla_len(tb[FRA_SRC]) != ops->addr_size)
 256                        goto errout;
 257
 258        if (frh->dst_len)
 259                if (tb[FRA_DST] == NULL ||
 260                    frh->dst_len > (ops->addr_size * 8) ||
 261                    nla_len(tb[FRA_DST]) != ops->addr_size)
 262                        goto errout;
 263
 264        err = 0;
 265errout:
 266        return err;
 267}
 268
 269static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 270{
 271        struct net *net = sock_net(skb->sk);
 272        struct fib_rule_hdr *frh = nlmsg_data(nlh);
 273        struct fib_rules_ops *ops = NULL;
 274        struct fib_rule *rule, *r, *last = NULL;
 275        struct nlattr *tb[FRA_MAX+1];
 276        int err = -EINVAL, unresolved = 0;
 277
 278        if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 279                goto errout;
 280
 281        ops = lookup_rules_ops(net, frh->family);
 282        if (ops == NULL) {
 283                err = -EAFNOSUPPORT;
 284                goto errout;
 285        }
 286
 287        err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
 288        if (err < 0)
 289                goto errout;
 290
 291        err = validate_rulemsg(frh, tb, ops);
 292        if (err < 0)
 293                goto errout;
 294
 295        rule = kzalloc(ops->rule_size, GFP_KERNEL);
 296        if (rule == NULL) {
 297                err = -ENOMEM;
 298                goto errout;
 299        }
 300        rule->fr_net = hold_net(net);
 301
 302        if (tb[FRA_PRIORITY])
 303                rule->pref = nla_get_u32(tb[FRA_PRIORITY]);
 304
 305        if (tb[FRA_IIFNAME]) {
 306                struct net_device *dev;
 307
 308                rule->iifindex = -1;
 309                nla_strlcpy(rule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
 310                dev = __dev_get_by_name(net, rule->iifname);
 311                if (dev)
 312                        rule->iifindex = dev->ifindex;
 313        }
 314
 315        if (tb[FRA_OIFNAME]) {
 316                struct net_device *dev;
 317
 318                rule->oifindex = -1;
 319                nla_strlcpy(rule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
 320                dev = __dev_get_by_name(net, rule->oifname);
 321                if (dev)
 322                        rule->oifindex = dev->ifindex;
 323        }
 324
 325        if (tb[FRA_FWMARK]) {
 326                rule->mark = nla_get_u32(tb[FRA_FWMARK]);
 327                if (rule->mark)
 328                        /* compatibility: if the mark value is non-zero all bits
 329                         * are compared unless a mask is explicitly specified.
 330                         */
 331                        rule->mark_mask = 0xFFFFFFFF;
 332        }
 333
 334        if (tb[FRA_FWMASK])
 335                rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
 336
 337        rule->action = frh->action;
 338        rule->flags = frh->flags;
 339        rule->table = frh_get_table(frh, tb);
 340
 341        if (!tb[FRA_PRIORITY] && ops->default_pref)
 342                rule->pref = ops->default_pref(ops);
 343
 344        err = -EINVAL;
 345        if (tb[FRA_GOTO]) {
 346                if (rule->action != FR_ACT_GOTO)
 347                        goto errout_free;
 348
 349                rule->target = nla_get_u32(tb[FRA_GOTO]);
 350                /* Backward jumps are prohibited to avoid endless loops */
 351                if (rule->target <= rule->pref)
 352                        goto errout_free;
 353
 354                list_for_each_entry(r, &ops->rules_list, list) {
 355                        if (r->pref == rule->target) {
 356                                RCU_INIT_POINTER(rule->ctarget, r);
 357                                break;
 358                        }
 359                }
 360
 361                if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
 362                        unresolved = 1;
 363        } else if (rule->action == FR_ACT_GOTO)
 364                goto errout_free;
 365
 366        err = ops->configure(rule, skb, frh, tb);
 367        if (err < 0)
 368                goto errout_free;
 369
 370        list_for_each_entry(r, &ops->rules_list, list) {
 371                if (r->pref > rule->pref)
 372                        break;
 373                last = r;
 374        }
 375
 376        fib_rule_get(rule);
 377
 378        if (last)
 379                list_add_rcu(&rule->list, &last->list);
 380        else
 381                list_add_rcu(&rule->list, &ops->rules_list);
 382
 383        if (ops->unresolved_rules) {
 384                /*
 385                 * There are unresolved goto rules in the list, check if
 386                 * any of them are pointing to this new rule.
 387                 */
 388                list_for_each_entry(r, &ops->rules_list, list) {
 389                        if (r->action == FR_ACT_GOTO &&
 390                            r->target == rule->pref &&
 391                            rtnl_dereference(r->ctarget) == NULL) {
 392                                rcu_assign_pointer(r->ctarget, rule);
 393                                if (--ops->unresolved_rules == 0)
 394                                        break;
 395                        }
 396                }
 397        }
 398
 399        if (rule->action == FR_ACT_GOTO)
 400                ops->nr_goto_rules++;
 401
 402        if (unresolved)
 403                ops->unresolved_rules++;
 404
 405        notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
 406        flush_route_cache(ops);
 407        rules_ops_put(ops);
 408        return 0;
 409
 410errout_free:
 411        release_net(rule->fr_net);
 412        kfree(rule);
 413errout:
 414        rules_ops_put(ops);
 415        return err;
 416}
 417
 418static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 419{
 420        struct net *net = sock_net(skb->sk);
 421        struct fib_rule_hdr *frh = nlmsg_data(nlh);
 422        struct fib_rules_ops *ops = NULL;
 423        struct fib_rule *rule, *tmp;
 424        struct nlattr *tb[FRA_MAX+1];
 425        int err = -EINVAL;
 426
 427        if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 428                goto errout;
 429
 430        ops = lookup_rules_ops(net, frh->family);
 431        if (ops == NULL) {
 432                err = -EAFNOSUPPORT;
 433                goto errout;
 434        }
 435
 436        err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
 437        if (err < 0)
 438                goto errout;
 439
 440        err = validate_rulemsg(frh, tb, ops);
 441        if (err < 0)
 442                goto errout;
 443
 444        list_for_each_entry(rule, &ops->rules_list, list) {
 445                if (frh->action && (frh->action != rule->action))
 446                        continue;
 447
 448                if (frh->table && (frh_get_table(frh, tb) != rule->table))
 449                        continue;
 450
 451                if (tb[FRA_PRIORITY] &&
 452                    (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
 453                        continue;
 454
 455                if (tb[FRA_IIFNAME] &&
 456                    nla_strcmp(tb[FRA_IIFNAME], rule->iifname))
 457                        continue;
 458
 459                if (tb[FRA_OIFNAME] &&
 460                    nla_strcmp(tb[FRA_OIFNAME], rule->oifname))
 461                        continue;
 462
 463                if (tb[FRA_FWMARK] &&
 464                    (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
 465                        continue;
 466
 467                if (tb[FRA_FWMASK] &&
 468                    (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
 469                        continue;
 470
 471                if (!ops->compare(rule, frh, tb))
 472                        continue;
 473
 474                if (rule->flags & FIB_RULE_PERMANENT) {
 475                        err = -EPERM;
 476                        goto errout;
 477                }
 478
 479                list_del_rcu(&rule->list);
 480
 481                if (rule->action == FR_ACT_GOTO) {
 482                        ops->nr_goto_rules--;
 483                        if (rtnl_dereference(rule->ctarget) == NULL)
 484                                ops->unresolved_rules--;
 485                }
 486
 487                /*
 488                 * Check if this rule is a target to any of them. If so,
 489                 * disable them. As this operation is eventually very
 490                 * expensive, it is only performed if goto rules have
 491                 * actually been added.
 492                 */
 493                if (ops->nr_goto_rules > 0) {
 494                        list_for_each_entry(tmp, &ops->rules_list, list) {
 495                                if (rtnl_dereference(tmp->ctarget) == rule) {
 496                                        RCU_INIT_POINTER(tmp->ctarget, NULL);
 497                                        ops->unresolved_rules++;
 498                                }
 499                        }
 500                }
 501
 502                notify_rule_change(RTM_DELRULE, rule, ops, nlh,
 503                                   NETLINK_CB(skb).pid);
 504                if (ops->delete)
 505                        ops->delete(rule);
 506                fib_rule_put(rule);
 507                flush_route_cache(ops);
 508                rules_ops_put(ops);
 509                return 0;
 510        }
 511
 512        err = -ENOENT;
 513errout:
 514        rules_ops_put(ops);
 515        return err;
 516}
 517
 518static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
 519                                         struct fib_rule *rule)
 520{
 521        size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
 522                         + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
 523                         + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
 524                         + nla_total_size(4) /* FRA_PRIORITY */
 525                         + nla_total_size(4) /* FRA_TABLE */
 526                         + nla_total_size(4) /* FRA_FWMARK */
 527                         + nla_total_size(4); /* FRA_FWMASK */
 528
 529        if (ops->nlmsg_payload)
 530                payload += ops->nlmsg_payload(rule);
 531
 532        return payload;
 533}
 534
 535static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
 536                            u32 pid, u32 seq, int type, int flags,
 537                            struct fib_rules_ops *ops)
 538{
 539        struct nlmsghdr *nlh;
 540        struct fib_rule_hdr *frh;
 541
 542        nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
 543        if (nlh == NULL)
 544                return -EMSGSIZE;
 545
 546        frh = nlmsg_data(nlh);
 547        frh->family = ops->family;
 548        frh->table = rule->table;
 549        if (nla_put_u32(skb, FRA_TABLE, rule->table))
 550                goto nla_put_failure;
 551        frh->res1 = 0;
 552        frh->res2 = 0;
 553        frh->action = rule->action;
 554        frh->flags = rule->flags;
 555
 556        if (rule->action == FR_ACT_GOTO &&
 557            rcu_access_pointer(rule->ctarget) == NULL)
 558                frh->flags |= FIB_RULE_UNRESOLVED;
 559
 560        if (rule->iifname[0]) {
 561                if (nla_put_string(skb, FRA_IIFNAME, rule->iifname))
 562                        goto nla_put_failure;
 563                if (rule->iifindex == -1)
 564                        frh->flags |= FIB_RULE_IIF_DETACHED;
 565        }
 566
 567        if (rule->oifname[0]) {
 568                if (nla_put_string(skb, FRA_OIFNAME, rule->oifname))
 569                        goto nla_put_failure;
 570                if (rule->oifindex == -1)
 571                        frh->flags |= FIB_RULE_OIF_DETACHED;
 572        }
 573
 574        if ((rule->pref &&
 575             nla_put_u32(skb, FRA_PRIORITY, rule->pref)) ||
 576            (rule->mark &&
 577             nla_put_u32(skb, FRA_FWMARK, rule->mark)) ||
 578            ((rule->mark_mask || rule->mark) &&
 579             nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) ||
 580            (rule->target &&
 581             nla_put_u32(skb, FRA_GOTO, rule->target)))
 582                goto nla_put_failure;
 583        if (ops->fill(rule, skb, frh) < 0)
 584                goto nla_put_failure;
 585
 586        return nlmsg_end(skb, nlh);
 587
 588nla_put_failure:
 589        nlmsg_cancel(skb, nlh);
 590        return -EMSGSIZE;
 591}
 592
 593static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
 594                      struct fib_rules_ops *ops)
 595{
 596        int idx = 0;
 597        struct fib_rule *rule;
 598
 599        rcu_read_lock();
 600        list_for_each_entry_rcu(rule, &ops->rules_list, list) {
 601                if (idx < cb->args[1])
 602                        goto skip;
 603
 604                if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
 605                                     cb->nlh->nlmsg_seq, RTM_NEWRULE,
 606                                     NLM_F_MULTI, ops) < 0)
 607                        break;
 608skip:
 609                idx++;
 610        }
 611        rcu_read_unlock();
 612        cb->args[1] = idx;
 613        rules_ops_put(ops);
 614
 615        return skb->len;
 616}
 617
 618static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 619{
 620        struct net *net = sock_net(skb->sk);
 621        struct fib_rules_ops *ops;
 622        int idx = 0, family;
 623
 624        family = rtnl_msg_family(cb->nlh);
 625        if (family != AF_UNSPEC) {
 626                /* Protocol specific dump request */
 627                ops = lookup_rules_ops(net, family);
 628                if (ops == NULL)
 629                        return -EAFNOSUPPORT;
 630
 631                return dump_rules(skb, cb, ops);
 632        }
 633
 634        rcu_read_lock();
 635        list_for_each_entry_rcu(ops, &net->rules_ops, list) {
 636                if (idx < cb->args[0] || !try_module_get(ops->owner))
 637                        goto skip;
 638
 639                if (dump_rules(skb, cb, ops) < 0)
 640                        break;
 641
 642                cb->args[1] = 0;
 643skip:
 644                idx++;
 645        }
 646        rcu_read_unlock();
 647        cb->args[0] = idx;
 648
 649        return skb->len;
 650}
 651
 652static void notify_rule_change(int event, struct fib_rule *rule,
 653                               struct fib_rules_ops *ops, struct nlmsghdr *nlh,
 654                               u32 pid)
 655{
 656        struct net *net;
 657        struct sk_buff *skb;
 658        int err = -ENOBUFS;
 659
 660        net = ops->fro_net;
 661        skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
 662        if (skb == NULL)
 663                goto errout;
 664
 665        err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
 666        if (err < 0) {
 667                /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
 668                WARN_ON(err == -EMSGSIZE);
 669                kfree_skb(skb);
 670                goto errout;
 671        }
 672
 673        rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
 674        return;
 675errout:
 676        if (err < 0)
 677                rtnl_set_sk_err(net, ops->nlgroup, err);
 678}
 679
 680static void attach_rules(struct list_head *rules, struct net_device *dev)
 681{
 682        struct fib_rule *rule;
 683
 684        list_for_each_entry(rule, rules, list) {
 685                if (rule->iifindex == -1 &&
 686                    strcmp(dev->name, rule->iifname) == 0)
 687                        rule->iifindex = dev->ifindex;
 688                if (rule->oifindex == -1 &&
 689                    strcmp(dev->name, rule->oifname) == 0)
 690                        rule->oifindex = dev->ifindex;
 691        }
 692}
 693
 694static void detach_rules(struct list_head *rules, struct net_device *dev)
 695{
 696        struct fib_rule *rule;
 697
 698        list_for_each_entry(rule, rules, list) {
 699                if (rule->iifindex == dev->ifindex)
 700                        rule->iifindex = -1;
 701                if (rule->oifindex == dev->ifindex)
 702                        rule->oifindex = -1;
 703        }
 704}
 705
 706
 707static int fib_rules_event(struct notifier_block *this, unsigned long event,
 708                            void *ptr)
 709{
 710        struct net_device *dev = ptr;
 711        struct net *net = dev_net(dev);
 712        struct fib_rules_ops *ops;
 713
 714        ASSERT_RTNL();
 715
 716        switch (event) {
 717        case NETDEV_REGISTER:
 718                list_for_each_entry(ops, &net->rules_ops, list)
 719                        attach_rules(&ops->rules_list, dev);
 720                break;
 721
 722        case NETDEV_UNREGISTER:
 723                list_for_each_entry(ops, &net->rules_ops, list)
 724                        detach_rules(&ops->rules_list, dev);
 725                break;
 726        }
 727
 728        return NOTIFY_DONE;
 729}
 730
 731static struct notifier_block fib_rules_notifier = {
 732        .notifier_call = fib_rules_event,
 733};
 734
 735static int __net_init fib_rules_net_init(struct net *net)
 736{
 737        INIT_LIST_HEAD(&net->rules_ops);
 738        spin_lock_init(&net->rules_mod_lock);
 739        return 0;
 740}
 741
 742static struct pernet_operations fib_rules_net_ops = {
 743        .init = fib_rules_net_init,
 744};
 745
 746static int __init fib_rules_init(void)
 747{
 748        int err;
 749        rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, NULL);
 750        rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, NULL);
 751        rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, NULL);
 752
 753        err = register_pernet_subsys(&fib_rules_net_ops);
 754        if (err < 0)
 755                goto fail;
 756
 757        err = register_netdevice_notifier(&fib_rules_notifier);
 758        if (err < 0)
 759                goto fail_unregister;
 760
 761        return 0;
 762
 763fail_unregister:
 764        unregister_pernet_subsys(&fib_rules_net_ops);
 765fail:
 766        rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
 767        rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
 768        rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
 769        return err;
 770}
 771
 772subsys_initcall(fib_rules_init);
 773
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