net/sched/cls_api.c

   1 /*
   2  * net/sched/cls_api.c  Packet classifier API.
   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
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  * Changes:
  12  *
  13  * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
  14  *
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/types.h>
  19 #include <linux/kernel.h>
  20 #include <linux/string.h>
  21 #include <linux/errno.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/init.h>
  24 #include <linux/kmod.h>
  25 #include <linux/err.h>
  26 #include <linux/slab.h>
  27 #include <net/net_namespace.h>
  28 #include <net/sock.h>
  29 #include <net/netlink.h>
  30 #include <net/pkt_sched.h>
  31 #include <net/pkt_cls.h>
  32
  33 /* The list of all installed classifier types */
  34 static LIST_HEAD(tcf_proto_base);
  35
  36 /* Protects list of registered TC modules. It is pure SMP lock. */
  37 static DEFINE_RWLOCK(cls_mod_lock);
  38
  39 /* Find classifier type by string name */
  40
  41 static const struct tcf_proto_ops *tcf_proto_lookup_ops(struct nlattr *kind)
  42 {
  43         const struct tcf_proto_ops *t, *res = NULL;
  44
  45         if (kind) {
  46                 read_lock(&cls_mod_lock);
  47                 list_for_each_entry(t, &tcf_proto_base, head) {
  48                         if (nla_strcmp(kind, t->kind) == 0) {
  49                                 if (try_module_get(t->owner))
  50                                         res = t;
  51                                 break;
  52                         }
  53                 }
  54                 read_unlock(&cls_mod_lock);
  55         }
  56         return res;
  57 }
  58
  59 /* Register(unregister) new classifier type */
  60
  61 int register_tcf_proto_ops(struct tcf_proto_ops *ops)
  62 {
  63         struct tcf_proto_ops *t;
  64         int rc = -EEXIST;
  65
  66         write_lock(&cls_mod_lock);
  67         list_for_each_entry(t, &tcf_proto_base, head)
  68                 if (!strcmp(ops->kind, t->kind))
  69                         goto out;
  70
  71         list_add_tail(&ops->head, &tcf_proto_base);
  72         rc = 0;
  73 out:
  74         write_unlock(&cls_mod_lock);
  75         return rc;
  76 }
  77 EXPORT_SYMBOL(register_tcf_proto_ops);
  78
  79 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
  80 {
  81         struct tcf_proto_ops *t;
  82         int rc = -ENOENT;
  83
  84         /* Wait for outstanding call_rcu()s, if any, from a
  85          * tcf_proto_ops's destroy() handler.
  86          */
  87         rcu_barrier();
  88
  89         write_lock(&cls_mod_lock);
  90         list_for_each_entry(t, &tcf_proto_base, head) {
  91                 if (t == ops) {
  92                         list_del(&t->head);
  93                         rc = 0;
  94                         break;
  95                 }
  96         }
  97         write_unlock(&cls_mod_lock);
  98         return rc;
  99 }
 100 EXPORT_SYMBOL(unregister_tcf_proto_ops);
 101
 102 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 103                           struct nlmsghdr *n, struct tcf_proto *tp,
 104                           unsigned long fh, int event, bool unicast);
 105
 106 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
 107                                  struct nlmsghdr *n,
 108                                  struct tcf_proto __rcu **chain, int event)
 109 {
 110         struct tcf_proto __rcu **it_chain;
 111         struct tcf_proto *tp;
 112
 113         for (it_chain = chain; (tp = rtnl_dereference(*it_chain)) != NULL;
 114              it_chain = &tp->next)
 115                 tfilter_notify(net, oskb, n, tp, 0, event, false);
 116 }
 117
 118 /* Select new prio value from the range, managed by kernel. */
 119
 120 static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 121 {
 122         u32 first = TC_H_MAKE(0xC0000000U, 0U);
 123
 124         if (tp)
 125                 first = tp->prio - 1;
 126
 127         return first;
 128 }
 129
 130 /* Add/change/delete/get a filter node */
 131
 132 static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
 133 {
 134         struct net *net = sock_net(skb->sk);
 135         struct nlattr *tca[TCA_MAX + 1];
 136         struct tcmsg *t;
 137         u32 protocol;
 138         u32 prio;
 139         u32 nprio;
 140         u32 parent;
 141         struct net_device *dev;
 142         struct Qdisc  *q;
 143         struct tcf_proto __rcu **back;
 144         struct tcf_proto __rcu **chain;
 145         struct tcf_proto *tp;
 146         const struct tcf_proto_ops *tp_ops;
 147         const struct Qdisc_class_ops *cops;
 148         unsigned long cl;
 149         unsigned long fh;
 150         int err;
 151         int tp_created = 0;
 152
 153         if ((n->nlmsg_type != RTM_GETTFILTER) &&
 154             !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
 155                 return -EPERM;
 156
 157 replay:
 158         err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL);
 159         if (err < 0)
 160                 return err;
 161
 162         t = nlmsg_data(n);
 163         protocol = TC_H_MIN(t->tcm_info);
 164         prio = TC_H_MAJ(t->tcm_info);
 165         nprio = prio;
 166         parent = t->tcm_parent;
 167         cl = 0;
 168
 169         if (prio == 0) {
 170                 switch (n->nlmsg_type) {
 171                 case RTM_DELTFILTER:
 172                         if (protocol || t->tcm_handle || tca[TCA_KIND])
 173                                 return -ENOENT;
 174                         break;
 175                 case RTM_NEWTFILTER:
 176                         /* If no priority is provided by the user,
 177                          * we allocate one.
 178                          */
 179                         if (n->nlmsg_flags & NLM_F_CREATE) {
 180                                 prio = TC_H_MAKE(0x80000000U, 0U);
 181                                 break;
 182                         }
 183                         /* fall-through */
 184                 default:
 185                         return -ENOENT;
 186                 }
 187         }
 188
 189         /* Find head of filter chain. */
 190
 191         /* Find link */
 192         dev = __dev_get_by_index(net, t->tcm_ifindex);
 193         if (dev == NULL)
 194                 return -ENODEV;
 195
 196         /* Find qdisc */
 197         if (!parent) {
 198                 q = dev->qdisc;
 199                 parent = q->handle;
 200         } else {
 201                 q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
 202                 if (q == NULL)
 203                         return -EINVAL;
 204         }
 205
 206         /* Is it classful? */
 207         cops = q->ops->cl_ops;
 208         if (!cops)
 209                 return -EINVAL;
 210
 211         if (cops->tcf_chain == NULL)
 212                 return -EOPNOTSUPP;
 213
 214         /* Do we search for filter, attached to class? */
 215         if (TC_H_MIN(parent)) {
 216                 cl = cops->get(q, parent);
 217                 if (cl == 0)
 218                         return -ENOENT;
 219         }
 220
 221         /* And the last stroke */
 222         chain = cops->tcf_chain(q, cl);
 223         err = -EINVAL;
 224         if (chain == NULL)
 225                 goto errout;
 226         if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
 227                 tfilter_notify_chain(net, skb, n, chain, RTM_DELTFILTER);
 228                 tcf_destroy_chain(chain);
 229                 err = 0;
 230                 goto errout;
 231         }
 232
 233         /* Check the chain for existence of proto-tcf with this priority */
 234         for (back = chain;
 235              (tp = rtnl_dereference(*back)) != NULL;
 236              back = &tp->next) {
 237                 if (tp->prio >= prio) {
 238                         if (tp->prio == prio) {
 239                                 if (!nprio ||
 240                                     (tp->protocol != protocol && protocol))
 241                                         goto errout;
 242                         } else
 243                                 tp = NULL;
 244                         break;
 245                 }
 246         }
 247
 248         if (tp == NULL) {
 249                 /* Proto-tcf does not exist, create new one */
 250
 251                 if (tca[TCA_KIND] == NULL || !protocol)
 252                         goto errout;
 253
 254                 err = -ENOENT;
 255                 if (n->nlmsg_type != RTM_NEWTFILTER ||
 256                     !(n->nlmsg_flags & NLM_F_CREATE))
 257                         goto errout;
 258
 259
 260                 /* Create new proto tcf */
 261
 262                 err = -ENOBUFS;
 263                 tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 264                 if (tp == NULL)
 265                         goto errout;
 266                 err = -ENOENT;
 267                 tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND]);
 268                 if (tp_ops == NULL) {
 269 #ifdef CONFIG_MODULES
 270                         struct nlattr *kind = tca[TCA_KIND];
 271                         char name[IFNAMSIZ];
 272
 273                         if (kind != NULL &&
 274                             nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
 275                                 rtnl_unlock();
 276                                 request_module("cls_%s", name);
 277                                 rtnl_lock();
 278                                 tp_ops = tcf_proto_lookup_ops(kind);
 279                                 /* We dropped the RTNL semaphore in order to
 280                                  * perform the module load.  So, even if we
 281                                  * succeeded in loading the module we have to
 282                                  * replay the request.  We indicate this using
 283                                  * -EAGAIN.
 284                                  */
 285                                 if (tp_ops != NULL) {
 286                                         module_put(tp_ops->owner);
 287                                         err = -EAGAIN;
 288                                 }
 289                         }
 290 #endif
 291                         kfree(tp);
 292                         goto errout;
 293                 }
 294                 tp->ops = tp_ops;
 295                 tp->protocol = protocol;
 296                 tp->prio = nprio ? :
 297                                TC_H_MAJ(tcf_auto_prio(rtnl_dereference(*back)));
 298                 tp->q = q;
 299                 tp->classify = tp_ops->classify;
 300                 tp->classid = parent;
 301
 302                 err = tp_ops->init(tp);
 303                 if (err != 0) {
 304                         module_put(tp_ops->owner);
 305                         kfree(tp);
 306                         goto errout;
 307                 }
 308
 309                 tp_created = 1;
 310
 311         } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind))
 312                 goto errout;
 313
 314         fh = tp->ops->get(tp, t->tcm_handle);
 315
 316         if (fh == 0) {
 317                 if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
 318                         struct tcf_proto *next = rtnl_dereference(tp->next);
 319
 320                         RCU_INIT_POINTER(*back, next);
 321
 322                         tfilter_notify(net, skb, n, tp, fh,
 323                                        RTM_DELTFILTER, false);
 324                         tcf_destroy(tp, true);
 325                         err = 0;
 326                         goto errout;
 327                 }
 328
 329                 err = -ENOENT;
 330                 if (n->nlmsg_type != RTM_NEWTFILTER ||
 331                     !(n->nlmsg_flags & NLM_F_CREATE))
 332                         goto errout;
 333         } else {
 334                 switch (n->nlmsg_type) {
 335                 case RTM_NEWTFILTER:
 336                         err = -EEXIST;
 337                         if (n->nlmsg_flags & NLM_F_EXCL) {
 338                                 if (tp_created)
 339                                         tcf_destroy(tp, true);
 340                                 goto errout;
 341                         }
 342                         break;
 343                 case RTM_DELTFILTER:
 344                         err = tp->ops->delete(tp, fh);
 345                         if (err == 0) {
 346                                 struct tcf_proto *next = rtnl_dereference(tp->next);
 347
 348                                 tfilter_notify(net, skb, n, tp,
 349                                                t->tcm_handle,
 350                                                RTM_DELTFILTER, false);
 351                                 if (tcf_destroy(tp, false))
 352                                         RCU_INIT_POINTER(*back, next);
 353                         }
 354                         goto errout;
 355                 case RTM_GETTFILTER:
 356                         err = tfilter_notify(net, skb, n, tp, fh,
 357                                              RTM_NEWTFILTER, true);
 358                         goto errout;
 359                 default:
 360                         err = -EINVAL;
 361                         goto errout;
 362                 }
 363         }
 364
 365         err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
 366                               n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE);
 367         if (err == 0) {
 368                 if (tp_created) {
 369                         RCU_INIT_POINTER(tp->next, rtnl_dereference(*back));
 370                         rcu_assign_pointer(*back, tp);
 371                 }
 372                 tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER, false);
 373         } else {
 374                 if (tp_created)
 375                         tcf_destroy(tp, true);
 376         }
 377
 378 errout:
 379         if (cl)
 380                 cops->put(q, cl);
 381         if (err == -EAGAIN)
 382                 /* Replay the request. */
 383                 goto replay;
 384         return err;
 385 }
 386
 387 static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 388                          struct tcf_proto *tp, unsigned long fh, u32 portid,
 389                          u32 seq, u16 flags, int event)
 390 {
 391         struct tcmsg *tcm;
 392         struct nlmsghdr  *nlh;
 393         unsigned char *b = skb_tail_pointer(skb);
 394
 395         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
 396         if (!nlh)
 397                 goto out_nlmsg_trim;
 398         tcm = nlmsg_data(nlh);
 399         tcm->tcm_family = AF_UNSPEC;
 400         tcm->tcm__pad1 = 0;
 401         tcm->tcm__pad2 = 0;
 402         tcm->tcm_ifindex = qdisc_dev(tp->q)->ifindex;
 403         tcm->tcm_parent = tp->classid;
 404         tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
 405         if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
 406                 goto nla_put_failure;
 407         tcm->tcm_handle = fh;
 408         if (RTM_DELTFILTER != event) {
 409                 tcm->tcm_handle = 0;
 410                 if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm) < 0)
 411                         goto nla_put_failure;
 412         }
 413         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 414         return skb->len;
 415
 416 out_nlmsg_trim:
 417 nla_put_failure:
 418         nlmsg_trim(skb, b);
 419         return -1;
 420 }
 421
 422 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 423                           struct nlmsghdr *n, struct tcf_proto *tp,
 424                           unsigned long fh, int event, bool unicast)
 425 {
 426         struct sk_buff *skb;
 427         u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
 428
 429         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 430         if (!skb)
 431                 return -ENOBUFS;
 432
 433         if (tcf_fill_node(net, skb, tp, fh, portid, n->nlmsg_seq, 0, event) <= 0) {
 434                 kfree_skb(skb);
 435                 return -EINVAL;
 436         }
 437
 438         if (unicast)
 439                 return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
 440
 441         return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
 442                               n->nlmsg_flags & NLM_F_ECHO);
 443 }
 444
 445 struct tcf_dump_args {
 446         struct tcf_walker w;
 447         struct sk_buff *skb;
 448         struct netlink_callback *cb;
 449 };
 450
 451 static int tcf_node_dump(struct tcf_proto *tp, unsigned long n,
 452                          struct tcf_walker *arg)
 453 {
 454         struct tcf_dump_args *a = (void *)arg;
 455         struct net *net = sock_net(a->skb->sk);
 456
 457         return tcf_fill_node(net, a->skb, tp, n, NETLINK_CB(a->cb->skb).portid,
 458                              a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
 459                              RTM_NEWTFILTER);
 460 }
 461
 462 /* called with RTNL */
 463 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
 464 {
 465         struct net *net = sock_net(skb->sk);
 466         int t;
 467         int s_t;
 468         struct net_device *dev;
 469         struct Qdisc *q;
 470         struct tcf_proto *tp, __rcu **chain;
 471         struct tcmsg *tcm = nlmsg_data(cb->nlh);
 472         unsigned long cl = 0;
 473         const struct Qdisc_class_ops *cops;
 474         struct tcf_dump_args arg;
 475
 476         if (nlmsg_len(cb->nlh) < sizeof(*tcm))
 477                 return skb->len;
 478         dev = __dev_get_by_index(net, tcm->tcm_ifindex);
 479         if (!dev)
 480                 return skb->len;
 481
 482         if (!tcm->tcm_parent)
 483                 q = dev->qdisc;
 484         else
 485                 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
 486         if (!q)
 487                 goto out;
 488         cops = q->ops->cl_ops;
 489         if (!cops)
 490                 goto errout;
 491         if (cops->tcf_chain == NULL)
 492                 goto errout;
 493         if (TC_H_MIN(tcm->tcm_parent)) {
 494                 cl = cops->get(q, tcm->tcm_parent);
 495                 if (cl == 0)
 496                         goto errout;
 497         }
 498         chain = cops->tcf_chain(q, cl);
 499         if (chain == NULL)
 500                 goto errout;
 501
 502         s_t = cb->args[0];
 503
 504         for (tp = rtnl_dereference(*chain), t = 0;
 505              tp; tp = rtnl_dereference(tp->next), t++) {
 506                 if (t < s_t)
 507                         continue;
 508                 if (TC_H_MAJ(tcm->tcm_info) &&
 509                     TC_H_MAJ(tcm->tcm_info) != tp->prio)
 510                         continue;
 511                 if (TC_H_MIN(tcm->tcm_info) &&
 512                     TC_H_MIN(tcm->tcm_info) != tp->protocol)
 513                         continue;
 514                 if (t > s_t)
 515                         memset(&cb->args[1], 0,
 516                                sizeof(cb->args)-sizeof(cb->args[0]));
 517                 if (cb->args[1] == 0) {
 518                         if (tcf_fill_node(net, skb, tp, 0,
 519                                           NETLINK_CB(cb->skb).portid,
 520                                           cb->nlh->nlmsg_seq, NLM_F_MULTI,
 521                                           RTM_NEWTFILTER) <= 0)
 522                                 break;
 523
 524                         cb->args[1] = 1;
 525                 }
 526                 if (tp->ops->walk == NULL)
 527                         continue;
 528                 arg.w.fn = tcf_node_dump;
 529                 arg.skb = skb;
 530                 arg.cb = cb;
 531                 arg.w.stop = 0;
 532                 arg.w.skip = cb->args[1] - 1;
 533                 arg.w.count = 0;
 534                 tp->ops->walk(tp, &arg.w);
 535                 cb->args[1] = arg.w.count + 1;
 536                 if (arg.w.stop)
 537                         break;
 538         }
 539
 540         cb->args[0] = t;
 541
 542 errout:
 543         if (cl)
 544                 cops->put(q, cl);
 545 out:
 546         return skb->len;
 547 }
 548
 549 void tcf_exts_destroy(struct tcf_exts *exts)
 550 {
 551 #ifdef CONFIG_NET_CLS_ACT
 552         LIST_HEAD(actions);
 553
 554         tcf_exts_to_list(exts, &actions);
 555         tcf_action_destroy(&actions, TCA_ACT_UNBIND);
 556         kfree(exts->actions);
 557         exts->nr_actions = 0;
 558 #endif
 559 }
 560 EXPORT_SYMBOL(tcf_exts_destroy);
 561
 562 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
 563                       struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr)
 564 {
 565 #ifdef CONFIG_NET_CLS_ACT
 566         {
 567                 struct tc_action *act;
 568
 569                 if (exts->police && tb[exts->police]) {
 570                         act = tcf_action_init_1(net, tb[exts->police], rate_tlv,
 571                                                 "police", ovr, TCA_ACT_BIND);
 572                         if (IS_ERR(act))
 573                                 return PTR_ERR(act);
 574
 575                         act->type = exts->type = TCA_OLD_COMPAT;
 576                         exts->actions[0] = act;
 577                         exts->nr_actions = 1;
 578                 } else if (exts->action && tb[exts->action]) {
 579                         LIST_HEAD(actions);
 580                         int err, i = 0;
 581
 582                         err = tcf_action_init(net, tb[exts->action], rate_tlv,
 583                                               NULL, ovr, TCA_ACT_BIND,
 584                                               &actions);
 585                         if (err)
 586                                 return err;
 587                         list_for_each_entry(act, &actions, list)
 588                                 exts->actions[i++] = act;
 589                         exts->nr_actions = i;
 590                 }
 591         }
 592 #else
 593         if ((exts->action && tb[exts->action]) ||
 594             (exts->police && tb[exts->police]))
 595                 return -EOPNOTSUPP;
 596 #endif
 597
 598         return 0;
 599 }
 600 EXPORT_SYMBOL(tcf_exts_validate);
 601
 602 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
 603                      struct tcf_exts *src)
 604 {
 605 #ifdef CONFIG_NET_CLS_ACT
 606         struct tcf_exts old = *dst;
 607
 608         tcf_tree_lock(tp);
 609         dst->nr_actions = src->nr_actions;
 610         dst->actions = src->actions;
 611         dst->type = src->type;
 612         tcf_tree_unlock(tp);
 613
 614         tcf_exts_destroy(&old);
 615 #endif
 616 }
 617 EXPORT_SYMBOL(tcf_exts_change);
 618
 619 #ifdef CONFIG_NET_CLS_ACT
 620 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
 621 {
 622         if (exts->nr_actions == 0)
 623                 return NULL;
 624         else
 625                 return exts->actions[0];
 626 }
 627 #endif
 628
 629 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
 630 {
 631 #ifdef CONFIG_NET_CLS_ACT
 632         struct nlattr *nest;
 633
 634         if (exts->action && exts->nr_actions) {
 635                 /*
 636                  * again for backward compatible mode - we want
 637                  * to work with both old and new modes of entering
 638                  * tc data even if iproute2  was newer - jhs
 639                  */
 640                 if (exts->type != TCA_OLD_COMPAT) {
 641                         LIST_HEAD(actions);
 642
 643                         nest = nla_nest_start(skb, exts->action);
 644                         if (nest == NULL)
 645                                 goto nla_put_failure;
 646
 647                         tcf_exts_to_list(exts, &actions);
 648                         if (tcf_action_dump(skb, &actions, 0, 0) < 0)
 649                                 goto nla_put_failure;
 650                         nla_nest_end(skb, nest);
 651                 } else if (exts->police) {
 652                         struct tc_action *act = tcf_exts_first_act(exts);
 653                         nest = nla_nest_start(skb, exts->police);
 654                         if (nest == NULL || !act)
 655                                 goto nla_put_failure;
 656                         if (tcf_action_dump_old(skb, act, 0, 0) < 0)
 657                                 goto nla_put_failure;
 658                         nla_nest_end(skb, nest);
 659                 }
 660         }
 661         return 0;
 662
 663 nla_put_failure:
 664         nla_nest_cancel(skb, nest);
 665         return -1;
 666 #else
 667         return 0;
 668 #endif
 669 }
 670 EXPORT_SYMBOL(tcf_exts_dump);
 671
 672
 673 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
 674 {
 675 #ifdef CONFIG_NET_CLS_ACT
 676         struct tc_action *a = tcf_exts_first_act(exts);
 677         if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
 678                 return -1;
 679 #endif
 680         return 0;
 681 }
 682 EXPORT_SYMBOL(tcf_exts_dump_stats);
 683
 684 static int __init tc_filter_init(void)
 685 {
 686         rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, NULL);
 687         rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, NULL);
 688         rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
 689                       tc_dump_tfilter, NULL);
 690
 691         return 0;
 692 }
 693
 694 subsys_initcall(tc_filter_init);