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;
 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         tp_created = 0;
 159
 160         err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL);
 161         if (err < 0)
 162                 return err;
 163
 164         t = nlmsg_data(n);
 165         protocol = TC_H_MIN(t->tcm_info);
 166         prio = TC_H_MAJ(t->tcm_info);
 167         nprio = prio;
 168         parent = t->tcm_parent;
 169         cl = 0;
 170
 171         if (prio == 0) {
 172                 switch (n->nlmsg_type) {
 173                 case RTM_DELTFILTER:
 174                         if (protocol || t->tcm_handle || tca[TCA_KIND])
 175                                 return -ENOENT;
 176                         break;
 177                 case RTM_NEWTFILTER:
 178                         /* If no priority is provided by the user,
 179                          * we allocate one.
 180                          */
 181                         if (n->nlmsg_flags & NLM_F_CREATE) {
 182                                 prio = TC_H_MAKE(0x80000000U, 0U);
 183                                 break;
 184                         }
 185                         /* fall-through */
 186                 default:
 187                         return -ENOENT;
 188                 }
 189         }
 190
 191         /* Find head of filter chain. */
 192
 193         /* Find link */
 194         dev = __dev_get_by_index(net, t->tcm_ifindex);
 195         if (dev == NULL)
 196                 return -ENODEV;
 197
 198         /* Find qdisc */
 199         if (!parent) {
 200                 q = dev->qdisc;
 201                 parent = q->handle;
 202         } else {
 203                 q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
 204                 if (q == NULL)
 205                         return -EINVAL;
 206         }
 207
 208         /* Is it classful? */
 209         cops = q->ops->cl_ops;
 210         if (!cops)
 211                 return -EINVAL;
 212
 213         if (cops->tcf_chain == NULL)
 214                 return -EOPNOTSUPP;
 215
 216         /* Do we search for filter, attached to class? */
 217         if (TC_H_MIN(parent)) {
 218                 cl = cops->get(q, parent);
 219                 if (cl == 0)
 220                         return -ENOENT;
 221         }
 222
 223         /* And the last stroke */
 224         chain = cops->tcf_chain(q, cl);
 225         err = -EINVAL;
 226         if (chain == NULL)
 227                 goto errout;
 228         if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
 229                 tfilter_notify_chain(net, skb, n, chain, RTM_DELTFILTER);
 230                 tcf_destroy_chain(chain);
 231                 err = 0;
 232                 goto errout;
 233         }
 234
 235         /* Check the chain for existence of proto-tcf with this priority */
 236         for (back = chain;
 237              (tp = rtnl_dereference(*back)) != NULL;
 238              back = &tp->next) {
 239                 if (tp->prio >= prio) {
 240                         if (tp->prio == prio) {
 241                                 if (!nprio ||
 242                                     (tp->protocol != protocol && protocol))
 243                                         goto errout;
 244                         } else
 245                                 tp = NULL;
 246                         break;
 247                 }
 248         }
 249
 250         if (tp == NULL) {
 251                 /* Proto-tcf does not exist, create new one */
 252
 253                 if (tca[TCA_KIND] == NULL || !protocol)
 254                         goto errout;
 255
 256                 err = -ENOENT;
 257                 if (n->nlmsg_type != RTM_NEWTFILTER ||
 258                     !(n->nlmsg_flags & NLM_F_CREATE))
 259                         goto errout;
 260
 261
 262                 /* Create new proto tcf */
 263
 264                 err = -ENOBUFS;
 265                 tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 266                 if (tp == NULL)
 267                         goto errout;
 268                 err = -ENOENT;
 269                 tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND]);
 270                 if (tp_ops == NULL) {
 271 #ifdef CONFIG_MODULES
 272                         struct nlattr *kind = tca[TCA_KIND];
 273                         char name[IFNAMSIZ];
 274
 275                         if (kind != NULL &&
 276                             nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
 277                                 rtnl_unlock();
 278                                 request_module("cls_%s", name);
 279                                 rtnl_lock();
 280                                 tp_ops = tcf_proto_lookup_ops(kind);
 281                                 /* We dropped the RTNL semaphore in order to
 282                                  * perform the module load.  So, even if we
 283                                  * succeeded in loading the module we have to
 284                                  * replay the request.  We indicate this using
 285                                  * -EAGAIN.
 286                                  */
 287                                 if (tp_ops != NULL) {
 288                                         module_put(tp_ops->owner);
 289                                         err = -EAGAIN;
 290                                 }
 291                         }
 292 #endif
 293                         kfree(tp);
 294                         goto errout;
 295                 }
 296                 tp->ops = tp_ops;
 297                 tp->protocol = protocol;
 298                 tp->prio = nprio ? :
 299                                TC_H_MAJ(tcf_auto_prio(rtnl_dereference(*back)));
 300                 tp->q = q;
 301                 tp->classify = tp_ops->classify;
 302                 tp->classid = parent;
 303
 304                 err = tp_ops->init(tp);
 305                 if (err != 0) {
 306                         module_put(tp_ops->owner);
 307                         kfree(tp);
 308                         goto errout;
 309                 }
 310
 311                 tp_created = 1;
 312
 313         } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind))
 314                 goto errout;
 315
 316         fh = tp->ops->get(tp, t->tcm_handle);
 317
 318         if (fh == 0) {
 319                 if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
 320                         struct tcf_proto *next = rtnl_dereference(tp->next);
 321
 322                         RCU_INIT_POINTER(*back, next);
 323
 324                         tfilter_notify(net, skb, n, tp, fh,
 325                                        RTM_DELTFILTER, false);
 326                         tcf_destroy(tp, true);
 327                         err = 0;
 328                         goto errout;
 329                 }
 330
 331                 err = -ENOENT;
 332                 if (n->nlmsg_type != RTM_NEWTFILTER ||
 333                     !(n->nlmsg_flags & NLM_F_CREATE))
 334                         goto errout;
 335         } else {
 336                 switch (n->nlmsg_type) {
 337                 case RTM_NEWTFILTER:
 338                         err = -EEXIST;
 339                         if (n->nlmsg_flags & NLM_F_EXCL) {
 340                                 if (tp_created)
 341                                         tcf_destroy(tp, true);
 342                                 goto errout;
 343                         }
 344                         break;
 345                 case RTM_DELTFILTER:
 346                         err = tp->ops->delete(tp, fh);
 347                         if (err == 0) {
 348                                 struct tcf_proto *next = rtnl_dereference(tp->next);
 349
 350                                 tfilter_notify(net, skb, n, tp,
 351                                                t->tcm_handle,
 352                                                RTM_DELTFILTER, false);
 353                                 if (tcf_destroy(tp, false))
 354                                         RCU_INIT_POINTER(*back, next);
 355                         }
 356                         goto errout;
 357                 case RTM_GETTFILTER:
 358                         err = tfilter_notify(net, skb, n, tp, fh,
 359                                              RTM_NEWTFILTER, true);
 360                         goto errout;
 361                 default:
 362                         err = -EINVAL;
 363                         goto errout;
 364                 }
 365         }
 366
 367         err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
 368                               n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE);
 369         if (err == 0) {
 370                 if (tp_created) {
 371                         RCU_INIT_POINTER(tp->next, rtnl_dereference(*back));
 372                         rcu_assign_pointer(*back, tp);
 373                 }
 374                 tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER, false);
 375         } else {
 376                 if (tp_created)
 377                         tcf_destroy(tp, true);
 378         }
 379
 380 errout:
 381         if (cl)
 382                 cops->put(q, cl);
 383         if (err == -EAGAIN)
 384                 /* Replay the request. */
 385                 goto replay;
 386         return err;
 387 }
 388
 389 static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 390                          struct tcf_proto *tp, unsigned long fh, u32 portid,
 391                          u32 seq, u16 flags, int event)
 392 {
 393         struct tcmsg *tcm;
 394         struct nlmsghdr  *nlh;
 395         unsigned char *b = skb_tail_pointer(skb);
 396
 397         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
 398         if (!nlh)
 399                 goto out_nlmsg_trim;
 400         tcm = nlmsg_data(nlh);
 401         tcm->tcm_family = AF_UNSPEC;
 402         tcm->tcm__pad1 = 0;
 403         tcm->tcm__pad2 = 0;
 404         tcm->tcm_ifindex = qdisc_dev(tp->q)->ifindex;
 405         tcm->tcm_parent = tp->classid;
 406         tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
 407         if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
 408                 goto nla_put_failure;
 409         tcm->tcm_handle = fh;
 410         if (RTM_DELTFILTER != event) {
 411                 tcm->tcm_handle = 0;
 412                 if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm) < 0)
 413                         goto nla_put_failure;
 414         }
 415         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 416         return skb->len;
 417
 418 out_nlmsg_trim:
 419 nla_put_failure:
 420         nlmsg_trim(skb, b);
 421         return -1;
 422 }
 423
 424 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 425                           struct nlmsghdr *n, struct tcf_proto *tp,
 426                           unsigned long fh, int event, bool unicast)
 427 {
 428         struct sk_buff *skb;
 429         u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
 430
 431         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 432         if (!skb)
 433                 return -ENOBUFS;
 434
 435         if (tcf_fill_node(net, skb, tp, fh, portid, n->nlmsg_seq,
 436                           n->nlmsg_flags, event) <= 0) {
 437                 kfree_skb(skb);
 438                 return -EINVAL;
 439         }
 440
 441         if (unicast)
 442                 return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
 443
 444         return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
 445                               n->nlmsg_flags & NLM_F_ECHO);
 446 }
 447
 448 struct tcf_dump_args {
 449         struct tcf_walker w;
 450         struct sk_buff *skb;
 451         struct netlink_callback *cb;
 452 };
 453
 454 static int tcf_node_dump(struct tcf_proto *tp, unsigned long n,
 455                          struct tcf_walker *arg)
 456 {
 457         struct tcf_dump_args *a = (void *)arg;
 458         struct net *net = sock_net(a->skb->sk);
 459
 460         return tcf_fill_node(net, a->skb, tp, n, NETLINK_CB(a->cb->skb).portid,
 461                              a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
 462                              RTM_NEWTFILTER);
 463 }
 464
 465 /* called with RTNL */
 466 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
 467 {
 468         struct net *net = sock_net(skb->sk);
 469         int t;
 470         int s_t;
 471         struct net_device *dev;
 472         struct Qdisc *q;
 473         struct tcf_proto *tp, __rcu **chain;
 474         struct tcmsg *tcm = nlmsg_data(cb->nlh);
 475         unsigned long cl = 0;
 476         const struct Qdisc_class_ops *cops;
 477         struct tcf_dump_args arg;
 478
 479         if (nlmsg_len(cb->nlh) < sizeof(*tcm))
 480                 return skb->len;
 481         dev = __dev_get_by_index(net, tcm->tcm_ifindex);
 482         if (!dev)
 483                 return skb->len;
 484
 485         if (!tcm->tcm_parent)
 486                 q = dev->qdisc;
 487         else
 488                 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
 489         if (!q)
 490                 goto out;
 491         cops = q->ops->cl_ops;
 492         if (!cops)
 493                 goto errout;
 494         if (cops->tcf_chain == NULL)
 495                 goto errout;
 496         if (TC_H_MIN(tcm->tcm_parent)) {
 497                 cl = cops->get(q, tcm->tcm_parent);
 498                 if (cl == 0)
 499                         goto errout;
 500         }
 501         chain = cops->tcf_chain(q, cl);
 502         if (chain == NULL)
 503                 goto errout;
 504
 505         s_t = cb->args[0];
 506
 507         for (tp = rtnl_dereference(*chain), t = 0;
 508              tp; tp = rtnl_dereference(tp->next), t++) {
 509                 if (t < s_t)
 510                         continue;
 511                 if (TC_H_MAJ(tcm->tcm_info) &&
 512                     TC_H_MAJ(tcm->tcm_info) != tp->prio)
 513                         continue;
 514                 if (TC_H_MIN(tcm->tcm_info) &&
 515                     TC_H_MIN(tcm->tcm_info) != tp->protocol)
 516                         continue;
 517                 if (t > s_t)
 518                         memset(&cb->args[1], 0,
 519                                sizeof(cb->args)-sizeof(cb->args[0]));
 520                 if (cb->args[1] == 0) {
 521                         if (tcf_fill_node(net, skb, tp, 0,
 522                                           NETLINK_CB(cb->skb).portid,
 523                                           cb->nlh->nlmsg_seq, NLM_F_MULTI,
 524                                           RTM_NEWTFILTER) <= 0)
 525                                 break;
 526
 527                         cb->args[1] = 1;
 528                 }
 529                 if (tp->ops->walk == NULL)
 530                         continue;
 531                 arg.w.fn = tcf_node_dump;
 532                 arg.skb = skb;
 533                 arg.cb = cb;
 534                 arg.w.stop = 0;
 535                 arg.w.skip = cb->args[1] - 1;
 536                 arg.w.count = 0;
 537                 tp->ops->walk(tp, &arg.w);
 538                 cb->args[1] = arg.w.count + 1;
 539                 if (arg.w.stop)
 540                         break;
 541         }
 542
 543         cb->args[0] = t;
 544
 545 errout:
 546         if (cl)
 547                 cops->put(q, cl);
 548 out:
 549         return skb->len;
 550 }
 551
 552 void tcf_exts_destroy(struct tcf_exts *exts)
 553 {
 554 #ifdef CONFIG_NET_CLS_ACT
 555         LIST_HEAD(actions);
 556
 557         tcf_exts_to_list(exts, &actions);
 558         tcf_action_destroy(&actions, TCA_ACT_UNBIND);
 559         kfree(exts->actions);
 560         exts->nr_actions = 0;
 561 #endif
 562 }
 563 EXPORT_SYMBOL(tcf_exts_destroy);
 564
 565 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
 566                       struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr)
 567 {
 568 #ifdef CONFIG_NET_CLS_ACT
 569         {
 570                 struct tc_action *act;
 571
 572                 if (exts->police && tb[exts->police]) {
 573                         act = tcf_action_init_1(net, tb[exts->police], rate_tlv,
 574                                                 "police", ovr, TCA_ACT_BIND);
 575                         if (IS_ERR(act))
 576                                 return PTR_ERR(act);
 577
 578                         act->type = exts->type = TCA_OLD_COMPAT;
 579                         exts->actions[0] = act;
 580                         exts->nr_actions = 1;
 581                 } else if (exts->action && tb[exts->action]) {
 582                         LIST_HEAD(actions);
 583                         int err, i = 0;
 584
 585                         err = tcf_action_init(net, tb[exts->action], rate_tlv,
 586                                               NULL, ovr, TCA_ACT_BIND,
 587                                               &actions);
 588                         if (err)
 589                                 return err;
 590                         list_for_each_entry(act, &actions, list)
 591                                 exts->actions[i++] = act;
 592                         exts->nr_actions = i;
 593                 }
 594         }
 595 #else
 596         if ((exts->action && tb[exts->action]) ||
 597             (exts->police && tb[exts->police]))
 598                 return -EOPNOTSUPP;
 599 #endif
 600
 601         return 0;
 602 }
 603 EXPORT_SYMBOL(tcf_exts_validate);
 604
 605 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
 606                      struct tcf_exts *src)
 607 {
 608 #ifdef CONFIG_NET_CLS_ACT
 609         struct tcf_exts old = *dst;
 610
 611         tcf_tree_lock(tp);
 612         dst->nr_actions = src->nr_actions;
 613         dst->actions = src->actions;
 614         dst->type = src->type;
 615         tcf_tree_unlock(tp);
 616
 617         tcf_exts_destroy(&old);
 618 #endif
 619 }
 620 EXPORT_SYMBOL(tcf_exts_change);
 621
 622 #ifdef CONFIG_NET_CLS_ACT
 623 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
 624 {
 625         if (exts->nr_actions == 0)
 626                 return NULL;
 627         else
 628                 return exts->actions[0];
 629 }
 630 #endif
 631
 632 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
 633 {
 634 #ifdef CONFIG_NET_CLS_ACT
 635         struct nlattr *nest;
 636
 637         if (exts->action && exts->nr_actions) {
 638                 /*
 639                  * again for backward compatible mode - we want
 640                  * to work with both old and new modes of entering
 641                  * tc data even if iproute2  was newer - jhs
 642                  */
 643                 if (exts->type != TCA_OLD_COMPAT) {
 644                         LIST_HEAD(actions);
 645
 646                         nest = nla_nest_start(skb, exts->action);
 647                         if (nest == NULL)
 648                                 goto nla_put_failure;
 649
 650                         tcf_exts_to_list(exts, &actions);
 651                         if (tcf_action_dump(skb, &actions, 0, 0) < 0)
 652                                 goto nla_put_failure;
 653                         nla_nest_end(skb, nest);
 654                 } else if (exts->police) {
 655                         struct tc_action *act = tcf_exts_first_act(exts);
 656                         nest = nla_nest_start(skb, exts->police);
 657                         if (nest == NULL || !act)
 658                                 goto nla_put_failure;
 659                         if (tcf_action_dump_old(skb, act, 0, 0) < 0)
 660                                 goto nla_put_failure;
 661                         nla_nest_end(skb, nest);
 662                 }
 663         }
 664         return 0;
 665
 666 nla_put_failure:
 667         nla_nest_cancel(skb, nest);
 668         return -1;
 669 #else
 670         return 0;
 671 #endif
 672 }
 673 EXPORT_SYMBOL(tcf_exts_dump);
 674
 675
 676 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
 677 {
 678 #ifdef CONFIG_NET_CLS_ACT
 679         struct tc_action *a = tcf_exts_first_act(exts);
 680         if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
 681                 return -1;
 682 #endif
 683         return 0;
 684 }
 685 EXPORT_SYMBOL(tcf_exts_dump_stats);
 686
 687 int tcf_exts_get_dev(struct net_device *dev, struct tcf_exts *exts,
 688                      struct net_device **hw_dev)
 689 {
 690 #ifdef CONFIG_NET_CLS_ACT
 691         const struct tc_action *a;
 692         LIST_HEAD(actions);
 693
 694         if (tc_no_actions(exts))
 695                 return -EINVAL;
 696
 697         tcf_exts_to_list(exts, &actions);
 698         list_for_each_entry(a, &actions, list) {
 699                 if (a->ops->get_dev) {
 700                         a->ops->get_dev(a, dev_net(dev), hw_dev);
 701                         break;
 702                 }
 703         }
 704         if (*hw_dev)
 705                 return 0;
 706 #endif
 707         return -EOPNOTSUPP;
 708 }
 709 EXPORT_SYMBOL(tcf_exts_get_dev);
 710
 711 static int __init tc_filter_init(void)
 712 {
 713         rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, NULL);
 714         rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, NULL);
 715         rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
 716                       tc_dump_tfilter, NULL);
 717
 718         return 0;
 719 }
 720
 721 subsys_initcall(tc_filter_init);