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/err.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/init.h>
  25 #include <linux/kmod.h>
  26 #include <linux/err.h>
  27 #include <linux/slab.h>
  28 #include <net/net_namespace.h>
  29 #include <net/sock.h>
  30 #include <net/netlink.h>
  31 #include <net/pkt_sched.h>
  32 #include <net/pkt_cls.h>
  33
  34 /* The list of all installed classifier types */
  35 static LIST_HEAD(tcf_proto_base);
  36
  37 /* Protects list of registered TC modules. It is pure SMP lock. */
  38 static DEFINE_RWLOCK(cls_mod_lock);
  39
  40 /* Find classifier type by string name */
  41
  42 static const struct tcf_proto_ops *tcf_proto_lookup_ops(const char *kind)
  43 {
  44         const struct tcf_proto_ops *t, *res = NULL;
  45
  46         if (kind) {
  47                 read_lock(&cls_mod_lock);
  48                 list_for_each_entry(t, &tcf_proto_base, head) {
  49                         if (strcmp(kind, t->kind) == 0) {
  50                                 if (try_module_get(t->owner))
  51                                         res = t;
  52                                 break;
  53                         }
  54                 }
  55                 read_unlock(&cls_mod_lock);
  56         }
  57         return res;
  58 }
  59
  60 /* Register(unregister) new classifier type */
  61
  62 int register_tcf_proto_ops(struct tcf_proto_ops *ops)
  63 {
  64         struct tcf_proto_ops *t;
  65         int rc = -EEXIST;
  66
  67         write_lock(&cls_mod_lock);
  68         list_for_each_entry(t, &tcf_proto_base, head)
  69                 if (!strcmp(ops->kind, t->kind))
  70                         goto out;
  71
  72         list_add_tail(&ops->head, &tcf_proto_base);
  73         rc = 0;
  74 out:
  75         write_unlock(&cls_mod_lock);
  76         return rc;
  77 }
  78 EXPORT_SYMBOL(register_tcf_proto_ops);
  79
  80 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
  81 {
  82         struct tcf_proto_ops *t;
  83         int rc = -ENOENT;
  84
  85         /* Wait for outstanding call_rcu()s, if any, from a
  86          * tcf_proto_ops's destroy() handler.
  87          */
  88         rcu_barrier();
  89
  90         write_lock(&cls_mod_lock);
  91         list_for_each_entry(t, &tcf_proto_base, head) {
  92                 if (t == ops) {
  93                         list_del(&t->head);
  94                         rc = 0;
  95                         break;
  96                 }
  97         }
  98         write_unlock(&cls_mod_lock);
  99         return rc;
 100 }
 101 EXPORT_SYMBOL(unregister_tcf_proto_ops);
 102
 103 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 104                           struct nlmsghdr *n, struct tcf_proto *tp,
 105                           unsigned long fh, int event, bool unicast);
 106
 107 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
 108                                  struct nlmsghdr *n,
 109                                  struct tcf_proto __rcu **chain, int event)
 110 {
 111         struct tcf_proto __rcu **it_chain;
 112         struct tcf_proto *tp;
 113
 114         for (it_chain = chain; (tp = rtnl_dereference(*it_chain)) != NULL;
 115              it_chain = &tp->next)
 116                 tfilter_notify(net, oskb, n, tp, 0, event, false);
 117 }
 118
 119 /* Select new prio value from the range, managed by kernel. */
 120
 121 static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 122 {
 123         u32 first = TC_H_MAKE(0xC0000000U, 0U);
 124
 125         if (tp)
 126                 first = tp->prio - 1;
 127
 128         return first;
 129 }
 130
 131 static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 132                                           u32 prio, u32 parent, struct Qdisc *q)
 133 {
 134         struct tcf_proto *tp;
 135         int err;
 136
 137         tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 138         if (!tp)
 139                 return ERR_PTR(-ENOBUFS);
 140
 141         err = -ENOENT;
 142         tp->ops = tcf_proto_lookup_ops(kind);
 143         if (!tp->ops) {
 144 #ifdef CONFIG_MODULES
 145                 rtnl_unlock();
 146                 request_module("cls_%s", kind);
 147                 rtnl_lock();
 148                 tp->ops = tcf_proto_lookup_ops(kind);
 149                 /* We dropped the RTNL semaphore in order to perform
 150                  * the module load. So, even if we succeeded in loading
 151                  * the module we have to replay the request. We indicate
 152                  * this using -EAGAIN.
 153                  */
 154                 if (tp->ops) {
 155                         module_put(tp->ops->owner);
 156                         err = -EAGAIN;
 157                 } else {
 158                         err = -ENOENT;
 159                 }
 160                 goto errout;
 161 #endif
 162         }
 163         tp->classify = tp->ops->classify;
 164         tp->protocol = protocol;
 165         tp->prio = prio;
 166         tp->classid = parent;
 167         tp->q = q;
 168
 169         err = tp->ops->init(tp);
 170         if (err) {
 171                 module_put(tp->ops->owner);
 172                 goto errout;
 173         }
 174         return tp;
 175
 176 errout:
 177         kfree(tp);
 178         return ERR_PTR(err);
 179 }
 180
 181 static bool tcf_proto_destroy(struct tcf_proto *tp, bool force)
 182 {
 183         if (tp->ops->destroy(tp, force)) {
 184                 module_put(tp->ops->owner);
 185                 kfree_rcu(tp, rcu);
 186                 return true;
 187         }
 188         return false;
 189 }
 190
 191 void tcf_destroy_chain(struct tcf_proto __rcu **fl)
 192 {
 193         struct tcf_proto *tp;
 194
 195         while ((tp = rtnl_dereference(*fl)) != NULL) {
 196                 RCU_INIT_POINTER(*fl, tp->next);
 197                 tcf_proto_destroy(tp, true);
 198         }
 199 }
 200 EXPORT_SYMBOL(tcf_destroy_chain);
 201
 202 /* Add/change/delete/get a filter node */
 203
 204 static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
 205 {
 206         struct net *net = sock_net(skb->sk);
 207         struct nlattr *tca[TCA_MAX + 1];
 208         struct tcmsg *t;
 209         u32 protocol;
 210         u32 prio;
 211         u32 nprio;
 212         u32 parent;
 213         struct net_device *dev;
 214         struct Qdisc  *q;
 215         struct tcf_proto __rcu **back;
 216         struct tcf_proto __rcu **chain;
 217         struct tcf_proto *next;
 218         struct tcf_proto *tp;
 219         const struct Qdisc_class_ops *cops;
 220         unsigned long cl;
 221         unsigned long fh;
 222         int err;
 223         int tp_created;
 224
 225         if ((n->nlmsg_type != RTM_GETTFILTER) &&
 226             !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
 227                 return -EPERM;
 228
 229 replay:
 230         tp_created = 0;
 231
 232         err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL);
 233         if (err < 0)
 234                 return err;
 235
 236         t = nlmsg_data(n);
 237         protocol = TC_H_MIN(t->tcm_info);
 238         prio = TC_H_MAJ(t->tcm_info);
 239         nprio = prio;
 240         parent = t->tcm_parent;
 241         cl = 0;
 242
 243         if (prio == 0) {
 244                 switch (n->nlmsg_type) {
 245                 case RTM_DELTFILTER:
 246                         if (protocol || t->tcm_handle || tca[TCA_KIND])
 247                                 return -ENOENT;
 248                         break;
 249                 case RTM_NEWTFILTER:
 250                         /* If no priority is provided by the user,
 251                          * we allocate one.
 252                          */
 253                         if (n->nlmsg_flags & NLM_F_CREATE) {
 254                                 prio = TC_H_MAKE(0x80000000U, 0U);
 255                                 break;
 256                         }
 257                         /* fall-through */
 258                 default:
 259                         return -ENOENT;
 260                 }
 261         }
 262
 263         /* Find head of filter chain. */
 264
 265         /* Find link */
 266         dev = __dev_get_by_index(net, t->tcm_ifindex);
 267         if (dev == NULL)
 268                 return -ENODEV;
 269
 270         /* Find qdisc */
 271         if (!parent) {
 272                 q = dev->qdisc;
 273                 parent = q->handle;
 274         } else {
 275                 q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
 276                 if (q == NULL)
 277                         return -EINVAL;
 278         }
 279
 280         /* Is it classful? */
 281         cops = q->ops->cl_ops;
 282         if (!cops)
 283                 return -EINVAL;
 284
 285         if (cops->tcf_chain == NULL)
 286                 return -EOPNOTSUPP;
 287
 288         /* Do we search for filter, attached to class? */
 289         if (TC_H_MIN(parent)) {
 290                 cl = cops->get(q, parent);
 291                 if (cl == 0)
 292                         return -ENOENT;
 293         }
 294
 295         /* And the last stroke */
 296         chain = cops->tcf_chain(q, cl);
 297         if (chain == NULL) {
 298                 err = -EINVAL;
 299                 goto errout;
 300         }
 301         if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
 302                 tfilter_notify_chain(net, skb, n, chain, RTM_DELTFILTER);
 303                 tcf_destroy_chain(chain);
 304                 err = 0;
 305                 goto errout;
 306         }
 307
 308         /* Check the chain for existence of proto-tcf with this priority */
 309         for (back = chain;
 310              (tp = rtnl_dereference(*back)) != NULL;
 311              back = &tp->next) {
 312                 if (tp->prio >= prio) {
 313                         if (tp->prio == prio) {
 314                                 if (!nprio ||
 315                                     (tp->protocol != protocol && protocol)) {
 316                                         err = -EINVAL;
 317                                         goto errout;
 318                                 }
 319                         } else {
 320                                 tp = NULL;
 321                         }
 322                         break;
 323                 }
 324         }
 325
 326         if (tp == NULL) {
 327                 /* Proto-tcf does not exist, create new one */
 328
 329                 if (tca[TCA_KIND] == NULL || !protocol) {
 330                         err = -EINVAL;
 331                         goto errout;
 332                 }
 333
 334                 if (n->nlmsg_type != RTM_NEWTFILTER ||
 335                     !(n->nlmsg_flags & NLM_F_CREATE)) {
 336                         err = -ENOENT;
 337                         goto errout;
 338                 }
 339
 340                 if (!nprio)
 341                         nprio = TC_H_MAJ(tcf_auto_prio(rtnl_dereference(*back)));
 342
 343                 tp = tcf_proto_create(nla_data(tca[TCA_KIND]),
 344                                       protocol, nprio, parent, q);
 345                 if (IS_ERR(tp)) {
 346                         err = PTR_ERR(tp);
 347                         goto errout;
 348                 }
 349                 tp_created = 1;
 350         } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
 351                 err = -EINVAL;
 352                 goto errout;
 353         }
 354
 355         fh = tp->ops->get(tp, t->tcm_handle);
 356
 357         if (fh == 0) {
 358                 if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
 359                         next = rtnl_dereference(tp->next);
 360                         RCU_INIT_POINTER(*back, next);
 361                         tfilter_notify(net, skb, n, tp, fh,
 362                                        RTM_DELTFILTER, false);
 363                         tcf_proto_destroy(tp, true);
 364                         err = 0;
 365                         goto errout;
 366                 }
 367
 368                 if (n->nlmsg_type != RTM_NEWTFILTER ||
 369                     !(n->nlmsg_flags & NLM_F_CREATE)) {
 370                         err = -ENOENT;
 371                         goto errout;
 372                 }
 373         } else {
 374                 switch (n->nlmsg_type) {
 375                 case RTM_NEWTFILTER:
 376                         if (n->nlmsg_flags & NLM_F_EXCL) {
 377                                 if (tp_created)
 378                                         tcf_proto_destroy(tp, true);
 379                                 err = -EEXIST;
 380                                 goto errout;
 381                         }
 382                         break;
 383                 case RTM_DELTFILTER:
 384                         err = tp->ops->delete(tp, fh);
 385                         if (err)
 386                                 goto errout;
 387                         next = rtnl_dereference(tp->next);
 388                         tfilter_notify(net, skb, n, tp, t->tcm_handle,
 389                                        RTM_DELTFILTER, false);
 390                         if (tcf_proto_destroy(tp, false))
 391                                 RCU_INIT_POINTER(*back, next);
 392                         goto errout;
 393                 case RTM_GETTFILTER:
 394                         err = tfilter_notify(net, skb, n, tp, fh,
 395                                              RTM_NEWTFILTER, true);
 396                         goto errout;
 397                 default:
 398                         err = -EINVAL;
 399                         goto errout;
 400                 }
 401         }
 402
 403         err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
 404                               n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE);
 405         if (err == 0) {
 406                 if (tp_created) {
 407                         RCU_INIT_POINTER(tp->next, rtnl_dereference(*back));
 408                         rcu_assign_pointer(*back, tp);
 409                 }
 410                 tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER, false);
 411         } else {
 412                 if (tp_created)
 413                         tcf_proto_destroy(tp, true);
 414         }
 415
 416 errout:
 417         if (cl)
 418                 cops->put(q, cl);
 419         if (err == -EAGAIN)
 420                 /* Replay the request. */
 421                 goto replay;
 422         return err;
 423 }
 424
 425 static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 426                          struct tcf_proto *tp, unsigned long fh, u32 portid,
 427                          u32 seq, u16 flags, int event)
 428 {
 429         struct tcmsg *tcm;
 430         struct nlmsghdr  *nlh;
 431         unsigned char *b = skb_tail_pointer(skb);
 432
 433         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
 434         if (!nlh)
 435                 goto out_nlmsg_trim;
 436         tcm = nlmsg_data(nlh);
 437         tcm->tcm_family = AF_UNSPEC;
 438         tcm->tcm__pad1 = 0;
 439         tcm->tcm__pad2 = 0;
 440         tcm->tcm_ifindex = qdisc_dev(tp->q)->ifindex;
 441         tcm->tcm_parent = tp->classid;
 442         tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
 443         if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
 444                 goto nla_put_failure;
 445         tcm->tcm_handle = fh;
 446         if (RTM_DELTFILTER != event) {
 447                 tcm->tcm_handle = 0;
 448                 if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm) < 0)
 449                         goto nla_put_failure;
 450         }
 451         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 452         return skb->len;
 453
 454 out_nlmsg_trim:
 455 nla_put_failure:
 456         nlmsg_trim(skb, b);
 457         return -1;
 458 }
 459
 460 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 461                           struct nlmsghdr *n, struct tcf_proto *tp,
 462                           unsigned long fh, int event, bool unicast)
 463 {
 464         struct sk_buff *skb;
 465         u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
 466
 467         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 468         if (!skb)
 469                 return -ENOBUFS;
 470
 471         if (tcf_fill_node(net, skb, tp, fh, portid, n->nlmsg_seq,
 472                           n->nlmsg_flags, event) <= 0) {
 473                 kfree_skb(skb);
 474                 return -EINVAL;
 475         }
 476
 477         if (unicast)
 478                 return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
 479
 480         return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
 481                               n->nlmsg_flags & NLM_F_ECHO);
 482 }
 483
 484 struct tcf_dump_args {
 485         struct tcf_walker w;
 486         struct sk_buff *skb;
 487         struct netlink_callback *cb;
 488 };
 489
 490 static int tcf_node_dump(struct tcf_proto *tp, unsigned long n,
 491                          struct tcf_walker *arg)
 492 {
 493         struct tcf_dump_args *a = (void *)arg;
 494         struct net *net = sock_net(a->skb->sk);
 495
 496         return tcf_fill_node(net, a->skb, tp, n, NETLINK_CB(a->cb->skb).portid,
 497                              a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
 498                              RTM_NEWTFILTER);
 499 }
 500
 501 /* called with RTNL */
 502 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
 503 {
 504         struct net *net = sock_net(skb->sk);
 505         int t;
 506         int s_t;
 507         struct net_device *dev;
 508         struct Qdisc *q;
 509         struct tcf_proto *tp, __rcu **chain;
 510         struct tcmsg *tcm = nlmsg_data(cb->nlh);
 511         unsigned long cl = 0;
 512         const struct Qdisc_class_ops *cops;
 513         struct tcf_dump_args arg;
 514
 515         if (nlmsg_len(cb->nlh) < sizeof(*tcm))
 516                 return skb->len;
 517         dev = __dev_get_by_index(net, tcm->tcm_ifindex);
 518         if (!dev)
 519                 return skb->len;
 520
 521         if (!tcm->tcm_parent)
 522                 q = dev->qdisc;
 523         else
 524                 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
 525         if (!q)
 526                 goto out;
 527         cops = q->ops->cl_ops;
 528         if (!cops)
 529                 goto errout;
 530         if (cops->tcf_chain == NULL)
 531                 goto errout;
 532         if (TC_H_MIN(tcm->tcm_parent)) {
 533                 cl = cops->get(q, tcm->tcm_parent);
 534                 if (cl == 0)
 535                         goto errout;
 536         }
 537         chain = cops->tcf_chain(q, cl);
 538         if (chain == NULL)
 539                 goto errout;
 540
 541         s_t = cb->args[0];
 542
 543         for (tp = rtnl_dereference(*chain), t = 0;
 544              tp; tp = rtnl_dereference(tp->next), t++) {
 545                 if (t < s_t)
 546                         continue;
 547                 if (TC_H_MAJ(tcm->tcm_info) &&
 548                     TC_H_MAJ(tcm->tcm_info) != tp->prio)
 549                         continue;
 550                 if (TC_H_MIN(tcm->tcm_info) &&
 551                     TC_H_MIN(tcm->tcm_info) != tp->protocol)
 552                         continue;
 553                 if (t > s_t)
 554                         memset(&cb->args[1], 0,
 555                                sizeof(cb->args)-sizeof(cb->args[0]));
 556                 if (cb->args[1] == 0) {
 557                         if (tcf_fill_node(net, skb, tp, 0,
 558                                           NETLINK_CB(cb->skb).portid,
 559                                           cb->nlh->nlmsg_seq, NLM_F_MULTI,
 560                                           RTM_NEWTFILTER) <= 0)
 561                                 break;
 562
 563                         cb->args[1] = 1;
 564                 }
 565                 if (tp->ops->walk == NULL)
 566                         continue;
 567                 arg.w.fn = tcf_node_dump;
 568                 arg.skb = skb;
 569                 arg.cb = cb;
 570                 arg.w.stop = 0;
 571                 arg.w.skip = cb->args[1] - 1;
 572                 arg.w.count = 0;
 573                 tp->ops->walk(tp, &arg.w);
 574                 cb->args[1] = arg.w.count + 1;
 575                 if (arg.w.stop)
 576                         break;
 577         }
 578
 579         cb->args[0] = t;
 580
 581 errout:
 582         if (cl)
 583                 cops->put(q, cl);
 584 out:
 585         return skb->len;
 586 }
 587
 588 void tcf_exts_destroy(struct tcf_exts *exts)
 589 {
 590 #ifdef CONFIG_NET_CLS_ACT
 591         LIST_HEAD(actions);
 592
 593         tcf_exts_to_list(exts, &actions);
 594         tcf_action_destroy(&actions, TCA_ACT_UNBIND);
 595         kfree(exts->actions);
 596         exts->nr_actions = 0;
 597 #endif
 598 }
 599 EXPORT_SYMBOL(tcf_exts_destroy);
 600
 601 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
 602                       struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr)
 603 {
 604 #ifdef CONFIG_NET_CLS_ACT
 605         {
 606                 struct tc_action *act;
 607
 608                 if (exts->police && tb[exts->police]) {
 609                         act = tcf_action_init_1(net, tb[exts->police], rate_tlv,
 610                                                 "police", ovr, TCA_ACT_BIND);
 611                         if (IS_ERR(act))
 612                                 return PTR_ERR(act);
 613
 614                         act->type = exts->type = TCA_OLD_COMPAT;
 615                         exts->actions[0] = act;
 616                         exts->nr_actions = 1;
 617                 } else if (exts->action && tb[exts->action]) {
 618                         LIST_HEAD(actions);
 619                         int err, i = 0;
 620
 621                         err = tcf_action_init(net, tb[exts->action], rate_tlv,
 622                                               NULL, ovr, TCA_ACT_BIND,
 623                                               &actions);
 624                         if (err)
 625                                 return err;
 626                         list_for_each_entry(act, &actions, list)
 627                                 exts->actions[i++] = act;
 628                         exts->nr_actions = i;
 629                 }
 630         }
 631 #else
 632         if ((exts->action && tb[exts->action]) ||
 633             (exts->police && tb[exts->police]))
 634                 return -EOPNOTSUPP;
 635 #endif
 636
 637         return 0;
 638 }
 639 EXPORT_SYMBOL(tcf_exts_validate);
 640
 641 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
 642                      struct tcf_exts *src)
 643 {
 644 #ifdef CONFIG_NET_CLS_ACT
 645         struct tcf_exts old = *dst;
 646
 647         tcf_tree_lock(tp);
 648         dst->nr_actions = src->nr_actions;
 649         dst->actions = src->actions;
 650         dst->type = src->type;
 651         tcf_tree_unlock(tp);
 652
 653         tcf_exts_destroy(&old);
 654 #endif
 655 }
 656 EXPORT_SYMBOL(tcf_exts_change);
 657
 658 #ifdef CONFIG_NET_CLS_ACT
 659 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
 660 {
 661         if (exts->nr_actions == 0)
 662                 return NULL;
 663         else
 664                 return exts->actions[0];
 665 }
 666 #endif
 667
 668 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
 669 {
 670 #ifdef CONFIG_NET_CLS_ACT
 671         struct nlattr *nest;
 672
 673         if (exts->action && exts->nr_actions) {
 674                 /*
 675                  * again for backward compatible mode - we want
 676                  * to work with both old and new modes of entering
 677                  * tc data even if iproute2  was newer - jhs
 678                  */
 679                 if (exts->type != TCA_OLD_COMPAT) {
 680                         LIST_HEAD(actions);
 681
 682                         nest = nla_nest_start(skb, exts->action);
 683                         if (nest == NULL)
 684                                 goto nla_put_failure;
 685
 686                         tcf_exts_to_list(exts, &actions);
 687                         if (tcf_action_dump(skb, &actions, 0, 0) < 0)
 688                                 goto nla_put_failure;
 689                         nla_nest_end(skb, nest);
 690                 } else if (exts->police) {
 691                         struct tc_action *act = tcf_exts_first_act(exts);
 692                         nest = nla_nest_start(skb, exts->police);
 693                         if (nest == NULL || !act)
 694                                 goto nla_put_failure;
 695                         if (tcf_action_dump_old(skb, act, 0, 0) < 0)
 696                                 goto nla_put_failure;
 697                         nla_nest_end(skb, nest);
 698                 }
 699         }
 700         return 0;
 701
 702 nla_put_failure:
 703         nla_nest_cancel(skb, nest);
 704         return -1;
 705 #else
 706         return 0;
 707 #endif
 708 }
 709 EXPORT_SYMBOL(tcf_exts_dump);
 710
 711
 712 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
 713 {
 714 #ifdef CONFIG_NET_CLS_ACT
 715         struct tc_action *a = tcf_exts_first_act(exts);
 716         if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
 717                 return -1;
 718 #endif
 719         return 0;
 720 }
 721 EXPORT_SYMBOL(tcf_exts_dump_stats);
 722
 723 int tcf_exts_get_dev(struct net_device *dev, struct tcf_exts *exts,
 724                      struct net_device **hw_dev)
 725 {
 726 #ifdef CONFIG_NET_CLS_ACT
 727         const struct tc_action *a;
 728         LIST_HEAD(actions);
 729
 730         if (tc_no_actions(exts))
 731                 return -EINVAL;
 732
 733         tcf_exts_to_list(exts, &actions);
 734         list_for_each_entry(a, &actions, list) {
 735                 if (a->ops->get_dev) {
 736                         a->ops->get_dev(a, dev_net(dev), hw_dev);
 737                         break;
 738                 }
 739         }
 740         if (*hw_dev)
 741                 return 0;
 742 #endif
 743         return -EOPNOTSUPP;
 744 }
 745 EXPORT_SYMBOL(tcf_exts_get_dev);
 746
 747 static int __init tc_filter_init(void)
 748 {
 749         rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, NULL);
 750         rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, NULL);
 751         rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
 752                       tc_dump_tfilter, NULL);
 753
 754         return 0;
 755 }
 756
 757 subsys_initcall(tc_filter_init);