net/sched/cls_bpf.c

   1 /*
   2  * Berkeley Packet Filter based traffic classifier
   3  *
   4  * Might be used to classify traffic through flexible, user-defined and
   5  * possibly JIT-ed BPF filters for traffic control as an alternative to
   6  * ematches.
   7  *
   8  * (C) 2013 Daniel Borkmann <dborkman@redhat.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/types.h>
  17 #include <linux/skbuff.h>
  18 #include <linux/filter.h>
  19 #include <linux/bpf.h>
  20
  21 #include <net/rtnetlink.h>
  22 #include <net/pkt_cls.h>
  23 #include <net/sock.h>
  24
  25 MODULE_LICENSE("GPL");
  26 MODULE_AUTHOR("Daniel Borkmann <dborkman@redhat.com>");
  27 MODULE_DESCRIPTION("TC BPF based classifier");
  28
  29 #define CLS_BPF_NAME_LEN        256
  30 #define CLS_BPF_SUPPORTED_GEN_FLAGS             \
  31         (TCA_CLS_FLAGS_SKIP_HW | TCA_CLS_FLAGS_SKIP_SW)
  32
  33 struct cls_bpf_head {
  34         struct list_head plist;
  35         u32 hgen;
  36         struct rcu_head rcu;
  37 };
  38
  39 struct cls_bpf_prog {
  40         struct bpf_prog *filter;
  41         struct list_head link;
  42         struct tcf_result res;
  43         bool exts_integrated;
  44         bool offloaded;
  45         u32 gen_flags;
  46         struct tcf_exts exts;
  47         u32 handle;
  48         u16 bpf_num_ops;
  49         struct sock_filter *bpf_ops;
  50         const char *bpf_name;
  51         struct tcf_proto *tp;
  52         struct rcu_head rcu;
  53 };
  54
  55 static const struct nla_policy bpf_policy[TCA_BPF_MAX + 1] = {
  56         [TCA_BPF_CLASSID]       = { .type = NLA_U32 },
  57         [TCA_BPF_FLAGS]         = { .type = NLA_U32 },
  58         [TCA_BPF_FLAGS_GEN]     = { .type = NLA_U32 },
  59         [TCA_BPF_FD]            = { .type = NLA_U32 },
  60         [TCA_BPF_NAME]          = { .type = NLA_NUL_STRING,
  61                                     .len = CLS_BPF_NAME_LEN },
  62         [TCA_BPF_OPS_LEN]       = { .type = NLA_U16 },
  63         [TCA_BPF_OPS]           = { .type = NLA_BINARY,
  64                                     .len = sizeof(struct sock_filter) * BPF_MAXINSNS },
  65 };
  66
  67 static int cls_bpf_exec_opcode(int code)
  68 {
  69         switch (code) {
  70         case TC_ACT_OK:
  71         case TC_ACT_SHOT:
  72         case TC_ACT_STOLEN:
  73         case TC_ACT_REDIRECT:
  74         case TC_ACT_UNSPEC:
  75                 return code;
  76         default:
  77                 return TC_ACT_UNSPEC;
  78         }
  79 }
  80
  81 static int cls_bpf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
  82                             struct tcf_result *res)
  83 {
  84         struct cls_bpf_head *head = rcu_dereference_bh(tp->root);
  85         bool at_ingress = skb_at_tc_ingress(skb);
  86         struct cls_bpf_prog *prog;
  87         int ret = -1;
  88
  89         /* Needed here for accessing maps. */
  90         rcu_read_lock();
  91         list_for_each_entry_rcu(prog, &head->plist, link) {
  92                 int filter_res;
  93
  94                 qdisc_skb_cb(skb)->tc_classid = prog->res.classid;
  95
  96                 if (tc_skip_sw(prog->gen_flags)) {
  97                         filter_res = prog->exts_integrated ? TC_ACT_UNSPEC : 0;
  98                 } else if (at_ingress) {
  99                         /* It is safe to push/pull even if skb_shared() */
 100                         __skb_push(skb, skb->mac_len);
 101                         bpf_compute_data_end(skb);
 102                         filter_res = BPF_PROG_RUN(prog->filter, skb);
 103                         __skb_pull(skb, skb->mac_len);
 104                 } else {
 105                         bpf_compute_data_end(skb);
 106                         filter_res = BPF_PROG_RUN(prog->filter, skb);
 107                 }
 108
 109                 if (prog->exts_integrated) {
 110                         res->class   = 0;
 111                         res->classid = TC_H_MAJ(prog->res.classid) |
 112                                        qdisc_skb_cb(skb)->tc_classid;
 113
 114                         ret = cls_bpf_exec_opcode(filter_res);
 115                         if (ret == TC_ACT_UNSPEC)
 116                                 continue;
 117                         break;
 118                 }
 119
 120                 if (filter_res == 0)
 121                         continue;
 122                 if (filter_res != -1) {
 123                         res->class   = 0;
 124                         res->classid = filter_res;
 125                 } else {
 126                         *res = prog->res;
 127                 }
 128
 129                 ret = tcf_exts_exec(skb, &prog->exts, res);
 130                 if (ret < 0)
 131                         continue;
 132
 133                 break;
 134         }
 135         rcu_read_unlock();
 136
 137         return ret;
 138 }
 139
 140 static bool cls_bpf_is_ebpf(const struct cls_bpf_prog *prog)
 141 {
 142         return !prog->bpf_ops;
 143 }
 144
 145 static int cls_bpf_offload_cmd(struct tcf_proto *tp, struct cls_bpf_prog *prog,
 146                                enum tc_clsbpf_command cmd)
 147 {
 148         struct net_device *dev = tp->q->dev_queue->dev;
 149         struct tc_cls_bpf_offload bpf_offload = {};
 150         struct tc_to_netdev offload;
 151         int err;
 152
 153         offload.type = TC_SETUP_CLSBPF;
 154         offload.cls_bpf = &bpf_offload;
 155
 156         bpf_offload.command = cmd;
 157         bpf_offload.exts = &prog->exts;
 158         bpf_offload.prog = prog->filter;
 159         bpf_offload.name = prog->bpf_name;
 160         bpf_offload.exts_integrated = prog->exts_integrated;
 161         bpf_offload.gen_flags = prog->gen_flags;
 162
 163         err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
 164                                             tp->protocol, &offload);
 165
 166         if (!err && (cmd == TC_CLSBPF_ADD || cmd == TC_CLSBPF_REPLACE))
 167                 prog->gen_flags |= TCA_CLS_FLAGS_IN_HW;
 168
 169         return err;
 170 }
 171
 172 static int cls_bpf_offload(struct tcf_proto *tp, struct cls_bpf_prog *prog,
 173                            struct cls_bpf_prog *oldprog)
 174 {
 175         struct net_device *dev = tp->q->dev_queue->dev;
 176         struct cls_bpf_prog *obj = prog;
 177         enum tc_clsbpf_command cmd;
 178         bool skip_sw;
 179         int ret;
 180
 181         skip_sw = tc_skip_sw(prog->gen_flags) ||
 182                 (oldprog && tc_skip_sw(oldprog->gen_flags));
 183
 184         if (oldprog && oldprog->offloaded) {
 185                 if (tc_should_offload(dev, tp, prog->gen_flags)) {
 186                         cmd = TC_CLSBPF_REPLACE;
 187                 } else if (!tc_skip_sw(prog->gen_flags)) {
 188                         obj = oldprog;
 189                         cmd = TC_CLSBPF_DESTROY;
 190                 } else {
 191                         return -EINVAL;
 192                 }
 193         } else {
 194                 if (!tc_should_offload(dev, tp, prog->gen_flags))
 195                         return skip_sw ? -EINVAL : 0;
 196                 cmd = TC_CLSBPF_ADD;
 197         }
 198
 199         ret = cls_bpf_offload_cmd(tp, obj, cmd);
 200         if (ret)
 201                 return skip_sw ? ret : 0;
 202
 203         obj->offloaded = true;
 204         if (oldprog)
 205                 oldprog->offloaded = false;
 206
 207         return 0;
 208 }
 209
 210 static void cls_bpf_stop_offload(struct tcf_proto *tp,
 211                                  struct cls_bpf_prog *prog)
 212 {
 213         int err;
 214
 215         if (!prog->offloaded)
 216                 return;
 217
 218         err = cls_bpf_offload_cmd(tp, prog, TC_CLSBPF_DESTROY);
 219         if (err) {
 220                 pr_err("Stopping hardware offload failed: %d\n", err);
 221                 return;
 222         }
 223
 224         prog->offloaded = false;
 225 }
 226
 227 static void cls_bpf_offload_update_stats(struct tcf_proto *tp,
 228                                          struct cls_bpf_prog *prog)
 229 {
 230         if (!prog->offloaded)
 231                 return;
 232
 233         cls_bpf_offload_cmd(tp, prog, TC_CLSBPF_STATS);
 234 }
 235
 236 static int cls_bpf_init(struct tcf_proto *tp)
 237 {
 238         struct cls_bpf_head *head;
 239
 240         head = kzalloc(sizeof(*head), GFP_KERNEL);
 241         if (head == NULL)
 242                 return -ENOBUFS;
 243
 244         INIT_LIST_HEAD_RCU(&head->plist);
 245         rcu_assign_pointer(tp->root, head);
 246
 247         return 0;
 248 }
 249
 250 static void __cls_bpf_delete_prog(struct cls_bpf_prog *prog)
 251 {
 252         tcf_exts_destroy(&prog->exts);
 253
 254         if (cls_bpf_is_ebpf(prog))
 255                 bpf_prog_put(prog->filter);
 256         else
 257                 bpf_prog_destroy(prog->filter);
 258
 259         kfree(prog->bpf_name);
 260         kfree(prog->bpf_ops);
 261         kfree(prog);
 262 }
 263
 264 static void cls_bpf_delete_prog_rcu(struct rcu_head *rcu)
 265 {
 266         __cls_bpf_delete_prog(container_of(rcu, struct cls_bpf_prog, rcu));
 267 }
 268
 269 static void __cls_bpf_delete(struct tcf_proto *tp, struct cls_bpf_prog *prog)
 270 {
 271         cls_bpf_stop_offload(tp, prog);
 272         list_del_rcu(&prog->link);
 273         tcf_unbind_filter(tp, &prog->res);
 274         call_rcu(&prog->rcu, cls_bpf_delete_prog_rcu);
 275 }
 276
 277 static int cls_bpf_delete(struct tcf_proto *tp, unsigned long arg)
 278 {
 279         __cls_bpf_delete(tp, (struct cls_bpf_prog *) arg);
 280         return 0;
 281 }
 282
 283 static bool cls_bpf_destroy(struct tcf_proto *tp, bool force)
 284 {
 285         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 286         struct cls_bpf_prog *prog, *tmp;
 287
 288         if (!force && !list_empty(&head->plist))
 289                 return false;
 290
 291         list_for_each_entry_safe(prog, tmp, &head->plist, link)
 292                 __cls_bpf_delete(tp, prog);
 293
 294         kfree_rcu(head, rcu);
 295         return true;
 296 }
 297
 298 static unsigned long cls_bpf_get(struct tcf_proto *tp, u32 handle)
 299 {
 300         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 301         struct cls_bpf_prog *prog;
 302         unsigned long ret = 0UL;
 303
 304         list_for_each_entry(prog, &head->plist, link) {
 305                 if (prog->handle == handle) {
 306                         ret = (unsigned long) prog;
 307                         break;
 308                 }
 309         }
 310
 311         return ret;
 312 }
 313
 314 static int cls_bpf_prog_from_ops(struct nlattr **tb, struct cls_bpf_prog *prog)
 315 {
 316         struct sock_filter *bpf_ops;
 317         struct sock_fprog_kern fprog_tmp;
 318         struct bpf_prog *fp;
 319         u16 bpf_size, bpf_num_ops;
 320         int ret;
 321
 322         bpf_num_ops = nla_get_u16(tb[TCA_BPF_OPS_LEN]);
 323         if (bpf_num_ops > BPF_MAXINSNS || bpf_num_ops == 0)
 324                 return -EINVAL;
 325
 326         bpf_size = bpf_num_ops * sizeof(*bpf_ops);
 327         if (bpf_size != nla_len(tb[TCA_BPF_OPS]))
 328                 return -EINVAL;
 329
 330         bpf_ops = kzalloc(bpf_size, GFP_KERNEL);
 331         if (bpf_ops == NULL)
 332                 return -ENOMEM;
 333
 334         memcpy(bpf_ops, nla_data(tb[TCA_BPF_OPS]), bpf_size);
 335
 336         fprog_tmp.len = bpf_num_ops;
 337         fprog_tmp.filter = bpf_ops;
 338
 339         ret = bpf_prog_create(&fp, &fprog_tmp);
 340         if (ret < 0) {
 341                 kfree(bpf_ops);
 342                 return ret;
 343         }
 344
 345         prog->bpf_ops = bpf_ops;
 346         prog->bpf_num_ops = bpf_num_ops;
 347         prog->bpf_name = NULL;
 348         prog->filter = fp;
 349
 350         return 0;
 351 }
 352
 353 static int cls_bpf_prog_from_efd(struct nlattr **tb, struct cls_bpf_prog *prog,
 354                                  const struct tcf_proto *tp)
 355 {
 356         struct bpf_prog *fp;
 357         char *name = NULL;
 358         u32 bpf_fd;
 359
 360         bpf_fd = nla_get_u32(tb[TCA_BPF_FD]);
 361
 362         fp = bpf_prog_get_type(bpf_fd, BPF_PROG_TYPE_SCHED_CLS);
 363         if (IS_ERR(fp))
 364                 return PTR_ERR(fp);
 365
 366         if (tb[TCA_BPF_NAME]) {
 367                 name = nla_memdup(tb[TCA_BPF_NAME], GFP_KERNEL);
 368                 if (!name) {
 369                         bpf_prog_put(fp);
 370                         return -ENOMEM;
 371                 }
 372         }
 373
 374         prog->bpf_ops = NULL;
 375         prog->bpf_name = name;
 376         prog->filter = fp;
 377
 378         if (fp->dst_needed && !(tp->q->flags & TCQ_F_INGRESS))
 379                 netif_keep_dst(qdisc_dev(tp->q));
 380
 381         return 0;
 382 }
 383
 384 static int cls_bpf_modify_existing(struct net *net, struct tcf_proto *tp,
 385                                    struct cls_bpf_prog *prog,
 386                                    unsigned long base, struct nlattr **tb,
 387                                    struct nlattr *est, bool ovr)
 388 {
 389         bool is_bpf, is_ebpf, have_exts = false;
 390         struct tcf_exts exts;
 391         u32 gen_flags = 0;
 392         int ret;
 393
 394         is_bpf = tb[TCA_BPF_OPS_LEN] && tb[TCA_BPF_OPS];
 395         is_ebpf = tb[TCA_BPF_FD];
 396         if ((!is_bpf && !is_ebpf) || (is_bpf && is_ebpf))
 397                 return -EINVAL;
 398
 399         ret = tcf_exts_init(&exts, TCA_BPF_ACT, TCA_BPF_POLICE);
 400         if (ret < 0)
 401                 return ret;
 402         ret = tcf_exts_validate(net, tp, tb, est, &exts, ovr);
 403         if (ret < 0)
 404                 goto errout;
 405
 406         if (tb[TCA_BPF_FLAGS]) {
 407                 u32 bpf_flags = nla_get_u32(tb[TCA_BPF_FLAGS]);
 408
 409                 if (bpf_flags & ~TCA_BPF_FLAG_ACT_DIRECT) {
 410                         ret = -EINVAL;
 411                         goto errout;
 412                 }
 413
 414                 have_exts = bpf_flags & TCA_BPF_FLAG_ACT_DIRECT;
 415         }
 416         if (tb[TCA_BPF_FLAGS_GEN]) {
 417                 gen_flags = nla_get_u32(tb[TCA_BPF_FLAGS_GEN]);
 418                 if (gen_flags & ~CLS_BPF_SUPPORTED_GEN_FLAGS ||
 419                     !tc_flags_valid(gen_flags)) {
 420                         ret = -EINVAL;
 421                         goto errout;
 422                 }
 423         }
 424
 425         prog->exts_integrated = have_exts;
 426         prog->gen_flags = gen_flags;
 427
 428         ret = is_bpf ? cls_bpf_prog_from_ops(tb, prog) :
 429                        cls_bpf_prog_from_efd(tb, prog, tp);
 430         if (ret < 0)
 431                 goto errout;
 432
 433         if (tb[TCA_BPF_CLASSID]) {
 434                 prog->res.classid = nla_get_u32(tb[TCA_BPF_CLASSID]);
 435                 tcf_bind_filter(tp, &prog->res, base);
 436         }
 437
 438         tcf_exts_change(tp, &prog->exts, &exts);
 439         return 0;
 440
 441 errout:
 442         tcf_exts_destroy(&exts);
 443         return ret;
 444 }
 445
 446 static u32 cls_bpf_grab_new_handle(struct tcf_proto *tp,
 447                                    struct cls_bpf_head *head)
 448 {
 449         unsigned int i = 0x80000000;
 450         u32 handle;
 451
 452         do {
 453                 if (++head->hgen == 0x7FFFFFFF)
 454                         head->hgen = 1;
 455         } while (--i > 0 && cls_bpf_get(tp, head->hgen));
 456
 457         if (unlikely(i == 0)) {
 458                 pr_err("Insufficient number of handles\n");
 459                 handle = 0;
 460         } else {
 461                 handle = head->hgen;
 462         }
 463
 464         return handle;
 465 }
 466
 467 static int cls_bpf_change(struct net *net, struct sk_buff *in_skb,
 468                           struct tcf_proto *tp, unsigned long base,
 469                           u32 handle, struct nlattr **tca,
 470                           unsigned long *arg, bool ovr)
 471 {
 472         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 473         struct cls_bpf_prog *oldprog = (struct cls_bpf_prog *) *arg;
 474         struct nlattr *tb[TCA_BPF_MAX + 1];
 475         struct cls_bpf_prog *prog;
 476         int ret;
 477
 478         if (tca[TCA_OPTIONS] == NULL)
 479                 return -EINVAL;
 480
 481         ret = nla_parse_nested(tb, TCA_BPF_MAX, tca[TCA_OPTIONS], bpf_policy,
 482                                NULL);
 483         if (ret < 0)
 484                 return ret;
 485
 486         prog = kzalloc(sizeof(*prog), GFP_KERNEL);
 487         if (!prog)
 488                 return -ENOBUFS;
 489
 490         ret = tcf_exts_init(&prog->exts, TCA_BPF_ACT, TCA_BPF_POLICE);
 491         if (ret < 0)
 492                 goto errout;
 493
 494         if (oldprog) {
 495                 if (handle && oldprog->handle != handle) {
 496                         ret = -EINVAL;
 497                         goto errout;
 498                 }
 499         }
 500
 501         if (handle == 0)
 502                 prog->handle = cls_bpf_grab_new_handle(tp, head);
 503         else
 504                 prog->handle = handle;
 505         if (prog->handle == 0) {
 506                 ret = -EINVAL;
 507                 goto errout;
 508         }
 509
 510         ret = cls_bpf_modify_existing(net, tp, prog, base, tb, tca[TCA_RATE],
 511                                       ovr);
 512         if (ret < 0)
 513                 goto errout;
 514
 515         ret = cls_bpf_offload(tp, prog, oldprog);
 516         if (ret) {
 517                 __cls_bpf_delete_prog(prog);
 518                 return ret;
 519         }
 520
 521         if (!tc_in_hw(prog->gen_flags))
 522                 prog->gen_flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 523
 524         if (oldprog) {
 525                 list_replace_rcu(&oldprog->link, &prog->link);
 526                 tcf_unbind_filter(tp, &oldprog->res);
 527                 call_rcu(&oldprog->rcu, cls_bpf_delete_prog_rcu);
 528         } else {
 529                 list_add_rcu(&prog->link, &head->plist);
 530         }
 531
 532         *arg = (unsigned long) prog;
 533         return 0;
 534
 535 errout:
 536         tcf_exts_destroy(&prog->exts);
 537         kfree(prog);
 538         return ret;
 539 }
 540
 541 static int cls_bpf_dump_bpf_info(const struct cls_bpf_prog *prog,
 542                                  struct sk_buff *skb)
 543 {
 544         struct nlattr *nla;
 545
 546         if (nla_put_u16(skb, TCA_BPF_OPS_LEN, prog->bpf_num_ops))
 547                 return -EMSGSIZE;
 548
 549         nla = nla_reserve(skb, TCA_BPF_OPS, prog->bpf_num_ops *
 550                           sizeof(struct sock_filter));
 551         if (nla == NULL)
 552                 return -EMSGSIZE;
 553
 554         memcpy(nla_data(nla), prog->bpf_ops, nla_len(nla));
 555
 556         return 0;
 557 }
 558
 559 static int cls_bpf_dump_ebpf_info(const struct cls_bpf_prog *prog,
 560                                   struct sk_buff *skb)
 561 {
 562         struct nlattr *nla;
 563
 564         if (prog->bpf_name &&
 565             nla_put_string(skb, TCA_BPF_NAME, prog->bpf_name))
 566                 return -EMSGSIZE;
 567
 568         nla = nla_reserve(skb, TCA_BPF_TAG, sizeof(prog->filter->tag));
 569         if (nla == NULL)
 570                 return -EMSGSIZE;
 571
 572         memcpy(nla_data(nla), prog->filter->tag, nla_len(nla));
 573
 574         return 0;
 575 }
 576
 577 static int cls_bpf_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 578                         struct sk_buff *skb, struct tcmsg *tm)
 579 {
 580         struct cls_bpf_prog *prog = (struct cls_bpf_prog *) fh;
 581         struct nlattr *nest;
 582         u32 bpf_flags = 0;
 583         int ret;
 584
 585         if (prog == NULL)
 586                 return skb->len;
 587
 588         tm->tcm_handle = prog->handle;
 589
 590         cls_bpf_offload_update_stats(tp, prog);
 591
 592         nest = nla_nest_start(skb, TCA_OPTIONS);
 593         if (nest == NULL)
 594                 goto nla_put_failure;
 595
 596         if (prog->res.classid &&
 597             nla_put_u32(skb, TCA_BPF_CLASSID, prog->res.classid))
 598                 goto nla_put_failure;
 599
 600         if (cls_bpf_is_ebpf(prog))
 601                 ret = cls_bpf_dump_ebpf_info(prog, skb);
 602         else
 603                 ret = cls_bpf_dump_bpf_info(prog, skb);
 604         if (ret)
 605                 goto nla_put_failure;
 606
 607         if (tcf_exts_dump(skb, &prog->exts) < 0)
 608                 goto nla_put_failure;
 609
 610         if (prog->exts_integrated)
 611                 bpf_flags |= TCA_BPF_FLAG_ACT_DIRECT;
 612         if (bpf_flags && nla_put_u32(skb, TCA_BPF_FLAGS, bpf_flags))
 613                 goto nla_put_failure;
 614         if (prog->gen_flags &&
 615             nla_put_u32(skb, TCA_BPF_FLAGS_GEN, prog->gen_flags))
 616                 goto nla_put_failure;
 617
 618         nla_nest_end(skb, nest);
 619
 620         if (tcf_exts_dump_stats(skb, &prog->exts) < 0)
 621                 goto nla_put_failure;
 622
 623         return skb->len;
 624
 625 nla_put_failure:
 626         nla_nest_cancel(skb, nest);
 627         return -1;
 628 }
 629
 630 static void cls_bpf_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 631 {
 632         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 633         struct cls_bpf_prog *prog;
 634
 635         list_for_each_entry(prog, &head->plist, link) {
 636                 if (arg->count < arg->skip)
 637                         goto skip;
 638                 if (arg->fn(tp, (unsigned long) prog, arg) < 0) {
 639                         arg->stop = 1;
 640                         break;
 641                 }
 642 skip:
 643                 arg->count++;
 644         }
 645 }
 646
 647 static struct tcf_proto_ops cls_bpf_ops __read_mostly = {
 648         .kind           =       "bpf",
 649         .owner          =       THIS_MODULE,
 650         .classify       =       cls_bpf_classify,
 651         .init           =       cls_bpf_init,
 652         .destroy        =       cls_bpf_destroy,
 653         .get            =       cls_bpf_get,
 654         .change         =       cls_bpf_change,
 655         .delete         =       cls_bpf_delete,
 656         .walk           =       cls_bpf_walk,
 657         .dump           =       cls_bpf_dump,
 658 };
 659
 660 static int __init cls_bpf_init_mod(void)
 661 {
 662         return register_tcf_proto_ops(&cls_bpf_ops);
 663 }
 664
 665 static void __exit cls_bpf_exit_mod(void)
 666 {
 667         unregister_tcf_proto_ops(&cls_bpf_ops);
 668 }
 669
 670 module_init(cls_bpf_init_mod);
 671 module_exit(cls_bpf_exit_mod);