net/sched/cls_bpf.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Berkeley Packet Filter based traffic classifier
   4  *
   5  * Might be used to classify traffic through flexible, user-defined and
   6  * possibly JIT-ed BPF filters for traffic control as an alternative to
   7  * ematches.
   8  *
   9  * (C) 2013 Daniel Borkmann <dborkman@redhat.com>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/filter.h>
  16 #include <linux/bpf.h>
  17 #include <linux/idr.h>
  18
  19 #include <net/rtnetlink.h>
  20 #include <net/pkt_cls.h>
  21 #include <net/sock.h>
  22 #include <net/tc_wrapper.h>
  23
  24 MODULE_LICENSE("GPL");
  25 MODULE_AUTHOR("Daniel Borkmann <dborkman@redhat.com>");
  26 MODULE_DESCRIPTION("TC BPF based classifier");
  27
  28 #define CLS_BPF_NAME_LEN        256
  29 #define CLS_BPF_SUPPORTED_GEN_FLAGS             \
  30         (TCA_CLS_FLAGS_SKIP_HW | TCA_CLS_FLAGS_SKIP_SW)
  31
  32 struct cls_bpf_head {
  33         struct list_head plist;
  34         struct idr handle_idr;
  35         struct rcu_head rcu;
  36 };
  37
  38 struct cls_bpf_prog {
  39         struct bpf_prog *filter;
  40         struct list_head link;
  41         struct tcf_result res;
  42         bool exts_integrated;
  43         u32 gen_flags;
  44         unsigned int in_hw_count;
  45         struct tcf_exts exts;
  46         u32 handle;
  47         u16 bpf_num_ops;
  48         struct sock_filter *bpf_ops;
  49         const char *bpf_name;
  50         struct tcf_proto *tp;
  51         struct rcu_work rwork;
  52 };
  53
  54 static const struct nla_policy bpf_policy[TCA_BPF_MAX + 1] = {
  55         [TCA_BPF_CLASSID]       = { .type = NLA_U32 },
  56         [TCA_BPF_FLAGS]         = { .type = NLA_U32 },
  57         [TCA_BPF_FLAGS_GEN]     = { .type = NLA_U32 },
  58         [TCA_BPF_FD]            = { .type = NLA_U32 },
  59         [TCA_BPF_NAME]          = { .type = NLA_NUL_STRING,
  60                                     .len = CLS_BPF_NAME_LEN },
  61         [TCA_BPF_OPS_LEN]       = { .type = NLA_U16 },
  62         [TCA_BPF_OPS]           = { .type = NLA_BINARY,
  63                                     .len = sizeof(struct sock_filter) * BPF_MAXINSNS },
  64 };
  65
  66 static int cls_bpf_exec_opcode(int code)
  67 {
  68         switch (code) {
  69         case TC_ACT_OK:
  70         case TC_ACT_SHOT:
  71         case TC_ACT_STOLEN:
  72         case TC_ACT_TRAP:
  73         case TC_ACT_REDIRECT:
  74         case TC_ACT_UNSPEC:
  75                 return code;
  76         default:
  77                 return TC_ACT_UNSPEC;
  78         }
  79 }
  80
  81 TC_INDIRECT_SCOPE int cls_bpf_classify(struct sk_buff *skb,
  82                                        const struct tcf_proto *tp,
  83                                        struct tcf_result *res)
  84 {
  85         struct cls_bpf_head *head = rcu_dereference_bh(tp->root);
  86         bool at_ingress = skb_at_tc_ingress(skb);
  87         struct cls_bpf_prog *prog;
  88         int ret = -1;
  89
  90         list_for_each_entry_rcu(prog, &head->plist, link) {
  91                 int filter_res;
  92
  93                 qdisc_skb_cb(skb)->tc_classid = prog->res.classid;
  94
  95                 if (tc_skip_sw(prog->gen_flags)) {
  96                         filter_res = prog->exts_integrated ? TC_ACT_UNSPEC : 0;
  97                 } else if (at_ingress) {
  98                         /* It is safe to push/pull even if skb_shared() */
  99                         __skb_push(skb, skb->mac_len);
 100                         bpf_compute_data_pointers(skb);
 101                         filter_res = bpf_prog_run(prog->filter, skb);
 102                         __skb_pull(skb, skb->mac_len);
 103                 } else {
 104                         bpf_compute_data_pointers(skb);
 105                         filter_res = bpf_prog_run(prog->filter, skb);
 106                 }
 107                 if (unlikely(!skb->tstamp && skb->mono_delivery_time))
 108                         skb->mono_delivery_time = 0;
 109
 110                 if (prog->exts_integrated) {
 111                         res->class   = 0;
 112                         res->classid = TC_H_MAJ(prog->res.classid) |
 113                                        qdisc_skb_cb(skb)->tc_classid;
 114
 115                         ret = cls_bpf_exec_opcode(filter_res);
 116                         if (ret == TC_ACT_UNSPEC)
 117                                 continue;
 118                         break;
 119                 }
 120
 121                 if (filter_res == 0)
 122                         continue;
 123                 if (filter_res != -1) {
 124                         res->class   = 0;
 125                         res->classid = filter_res;
 126                 } else {
 127                         *res = prog->res;
 128                 }
 129
 130                 ret = tcf_exts_exec(skb, &prog->exts, res);
 131                 if (ret < 0)
 132                         continue;
 133
 134                 break;
 135         }
 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                                struct cls_bpf_prog *oldprog,
 147                                struct netlink_ext_ack *extack)
 148 {
 149         struct tcf_block *block = tp->chain->block;
 150         struct tc_cls_bpf_offload cls_bpf = {};
 151         struct cls_bpf_prog *obj;
 152         bool skip_sw;
 153         int err;
 154
 155         skip_sw = prog && tc_skip_sw(prog->gen_flags);
 156         obj = prog ?: oldprog;
 157
 158         tc_cls_common_offload_init(&cls_bpf.common, tp, obj->gen_flags, extack);
 159         cls_bpf.command = TC_CLSBPF_OFFLOAD;
 160         cls_bpf.exts = &obj->exts;
 161         cls_bpf.prog = prog ? prog->filter : NULL;
 162         cls_bpf.oldprog = oldprog ? oldprog->filter : NULL;
 163         cls_bpf.name = obj->bpf_name;
 164         cls_bpf.exts_integrated = obj->exts_integrated;
 165
 166         if (oldprog && prog)
 167                 err = tc_setup_cb_replace(block, tp, TC_SETUP_CLSBPF, &cls_bpf,
 168                                           skip_sw, &oldprog->gen_flags,
 169                                           &oldprog->in_hw_count,
 170                                           &prog->gen_flags, &prog->in_hw_count,
 171                                           true);
 172         else if (prog)
 173                 err = tc_setup_cb_add(block, tp, TC_SETUP_CLSBPF, &cls_bpf,
 174                                       skip_sw, &prog->gen_flags,
 175                                       &prog->in_hw_count, true);
 176         else
 177                 err = tc_setup_cb_destroy(block, tp, TC_SETUP_CLSBPF, &cls_bpf,
 178                                           skip_sw, &oldprog->gen_flags,
 179                                           &oldprog->in_hw_count, true);
 180
 181         if (prog && err) {
 182                 cls_bpf_offload_cmd(tp, oldprog, prog, extack);
 183                 return err;
 184         }
 185
 186         if (prog && skip_sw && !(prog->gen_flags & TCA_CLS_FLAGS_IN_HW))
 187                 return -EINVAL;
 188
 189         return 0;
 190 }
 191
 192 static u32 cls_bpf_flags(u32 flags)
 193 {
 194         return flags & CLS_BPF_SUPPORTED_GEN_FLAGS;
 195 }
 196
 197 static int cls_bpf_offload(struct tcf_proto *tp, struct cls_bpf_prog *prog,
 198                            struct cls_bpf_prog *oldprog,
 199                            struct netlink_ext_ack *extack)
 200 {
 201         if (prog && oldprog &&
 202             cls_bpf_flags(prog->gen_flags) !=
 203             cls_bpf_flags(oldprog->gen_flags))
 204                 return -EINVAL;
 205
 206         if (prog && tc_skip_hw(prog->gen_flags))
 207                 prog = NULL;
 208         if (oldprog && tc_skip_hw(oldprog->gen_flags))
 209                 oldprog = NULL;
 210         if (!prog && !oldprog)
 211                 return 0;
 212
 213         return cls_bpf_offload_cmd(tp, prog, oldprog, extack);
 214 }
 215
 216 static void cls_bpf_stop_offload(struct tcf_proto *tp,
 217                                  struct cls_bpf_prog *prog,
 218                                  struct netlink_ext_ack *extack)
 219 {
 220         int err;
 221
 222         err = cls_bpf_offload_cmd(tp, NULL, prog, extack);
 223         if (err)
 224                 pr_err("Stopping hardware offload failed: %d\n", err);
 225 }
 226
 227 static void cls_bpf_offload_update_stats(struct tcf_proto *tp,
 228                                          struct cls_bpf_prog *prog)
 229 {
 230         struct tcf_block *block = tp->chain->block;
 231         struct tc_cls_bpf_offload cls_bpf = {};
 232
 233         tc_cls_common_offload_init(&cls_bpf.common, tp, prog->gen_flags, NULL);
 234         cls_bpf.command = TC_CLSBPF_STATS;
 235         cls_bpf.exts = &prog->exts;
 236         cls_bpf.prog = prog->filter;
 237         cls_bpf.name = prog->bpf_name;
 238         cls_bpf.exts_integrated = prog->exts_integrated;
 239
 240         tc_setup_cb_call(block, TC_SETUP_CLSBPF, &cls_bpf, false, true);
 241 }
 242
 243 static int cls_bpf_init(struct tcf_proto *tp)
 244 {
 245         struct cls_bpf_head *head;
 246
 247         head = kzalloc(sizeof(*head), GFP_KERNEL);
 248         if (head == NULL)
 249                 return -ENOBUFS;
 250
 251         INIT_LIST_HEAD_RCU(&head->plist);
 252         idr_init(&head->handle_idr);
 253         rcu_assign_pointer(tp->root, head);
 254
 255         return 0;
 256 }
 257
 258 static void cls_bpf_free_parms(struct cls_bpf_prog *prog)
 259 {
 260         if (cls_bpf_is_ebpf(prog))
 261                 bpf_prog_put(prog->filter);
 262         else
 263                 bpf_prog_destroy(prog->filter);
 264
 265         kfree(prog->bpf_name);
 266         kfree(prog->bpf_ops);
 267 }
 268
 269 static void __cls_bpf_delete_prog(struct cls_bpf_prog *prog)
 270 {
 271         tcf_exts_destroy(&prog->exts);
 272         tcf_exts_put_net(&prog->exts);
 273
 274         cls_bpf_free_parms(prog);
 275         kfree(prog);
 276 }
 277
 278 static void cls_bpf_delete_prog_work(struct work_struct *work)
 279 {
 280         struct cls_bpf_prog *prog = container_of(to_rcu_work(work),
 281                                                  struct cls_bpf_prog,
 282                                                  rwork);
 283         rtnl_lock();
 284         __cls_bpf_delete_prog(prog);
 285         rtnl_unlock();
 286 }
 287
 288 static void __cls_bpf_delete(struct tcf_proto *tp, struct cls_bpf_prog *prog,
 289                              struct netlink_ext_ack *extack)
 290 {
 291         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 292
 293         idr_remove(&head->handle_idr, prog->handle);
 294         cls_bpf_stop_offload(tp, prog, extack);
 295         list_del_rcu(&prog->link);
 296         tcf_unbind_filter(tp, &prog->res);
 297         if (tcf_exts_get_net(&prog->exts))
 298                 tcf_queue_work(&prog->rwork, cls_bpf_delete_prog_work);
 299         else
 300                 __cls_bpf_delete_prog(prog);
 301 }
 302
 303 static int cls_bpf_delete(struct tcf_proto *tp, void *arg, bool *last,
 304                           bool rtnl_held, struct netlink_ext_ack *extack)
 305 {
 306         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 307
 308         __cls_bpf_delete(tp, arg, extack);
 309         *last = list_empty(&head->plist);
 310         return 0;
 311 }
 312
 313 static void cls_bpf_destroy(struct tcf_proto *tp, bool rtnl_held,
 314                             struct netlink_ext_ack *extack)
 315 {
 316         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 317         struct cls_bpf_prog *prog, *tmp;
 318
 319         list_for_each_entry_safe(prog, tmp, &head->plist, link)
 320                 __cls_bpf_delete(tp, prog, extack);
 321
 322         idr_destroy(&head->handle_idr);
 323         kfree_rcu(head, rcu);
 324 }
 325
 326 static void *cls_bpf_get(struct tcf_proto *tp, u32 handle)
 327 {
 328         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 329         struct cls_bpf_prog *prog;
 330
 331         list_for_each_entry(prog, &head->plist, link) {
 332                 if (prog->handle == handle)
 333                         return prog;
 334         }
 335
 336         return NULL;
 337 }
 338
 339 static int cls_bpf_prog_from_ops(struct nlattr **tb, struct cls_bpf_prog *prog)
 340 {
 341         struct sock_filter *bpf_ops;
 342         struct sock_fprog_kern fprog_tmp;
 343         struct bpf_prog *fp;
 344         u16 bpf_size, bpf_num_ops;
 345         int ret;
 346
 347         bpf_num_ops = nla_get_u16(tb[TCA_BPF_OPS_LEN]);
 348         if (bpf_num_ops > BPF_MAXINSNS || bpf_num_ops == 0)
 349                 return -EINVAL;
 350
 351         bpf_size = bpf_num_ops * sizeof(*bpf_ops);
 352         if (bpf_size != nla_len(tb[TCA_BPF_OPS]))
 353                 return -EINVAL;
 354
 355         bpf_ops = kmemdup(nla_data(tb[TCA_BPF_OPS]), bpf_size, GFP_KERNEL);
 356         if (bpf_ops == NULL)
 357                 return -ENOMEM;
 358
 359         fprog_tmp.len = bpf_num_ops;
 360         fprog_tmp.filter = bpf_ops;
 361
 362         ret = bpf_prog_create(&fp, &fprog_tmp);
 363         if (ret < 0) {
 364                 kfree(bpf_ops);
 365                 return ret;
 366         }
 367
 368         prog->bpf_ops = bpf_ops;
 369         prog->bpf_num_ops = bpf_num_ops;
 370         prog->bpf_name = NULL;
 371         prog->filter = fp;
 372
 373         return 0;
 374 }
 375
 376 static int cls_bpf_prog_from_efd(struct nlattr **tb, struct cls_bpf_prog *prog,
 377                                  u32 gen_flags, const struct tcf_proto *tp)
 378 {
 379         struct bpf_prog *fp;
 380         char *name = NULL;
 381         bool skip_sw;
 382         u32 bpf_fd;
 383
 384         bpf_fd = nla_get_u32(tb[TCA_BPF_FD]);
 385         skip_sw = gen_flags & TCA_CLS_FLAGS_SKIP_SW;
 386
 387         fp = bpf_prog_get_type_dev(bpf_fd, BPF_PROG_TYPE_SCHED_CLS, skip_sw);
 388         if (IS_ERR(fp))
 389                 return PTR_ERR(fp);
 390
 391         if (tb[TCA_BPF_NAME]) {
 392                 name = nla_memdup(tb[TCA_BPF_NAME], GFP_KERNEL);
 393                 if (!name) {
 394                         bpf_prog_put(fp);
 395                         return -ENOMEM;
 396                 }
 397         }
 398
 399         prog->bpf_ops = NULL;
 400         prog->bpf_name = name;
 401         prog->filter = fp;
 402
 403         if (fp->dst_needed)
 404                 tcf_block_netif_keep_dst(tp->chain->block);
 405
 406         return 0;
 407 }
 408
 409 static int cls_bpf_set_parms(struct net *net, struct tcf_proto *tp,
 410                              struct cls_bpf_prog *prog, unsigned long base,
 411                              struct nlattr **tb, struct nlattr *est, u32 flags,
 412                              struct netlink_ext_ack *extack)
 413 {
 414         bool is_bpf, is_ebpf, have_exts = false;
 415         u32 gen_flags = 0;
 416         int ret;
 417
 418         is_bpf = tb[TCA_BPF_OPS_LEN] && tb[TCA_BPF_OPS];
 419         is_ebpf = tb[TCA_BPF_FD];
 420         if ((!is_bpf && !is_ebpf) || (is_bpf && is_ebpf))
 421                 return -EINVAL;
 422
 423         ret = tcf_exts_validate(net, tp, tb, est, &prog->exts, flags,
 424                                 extack);
 425         if (ret < 0)
 426                 return ret;
 427
 428         if (tb[TCA_BPF_FLAGS]) {
 429                 u32 bpf_flags = nla_get_u32(tb[TCA_BPF_FLAGS]);
 430
 431                 if (bpf_flags & ~TCA_BPF_FLAG_ACT_DIRECT)
 432                         return -EINVAL;
 433
 434                 have_exts = bpf_flags & TCA_BPF_FLAG_ACT_DIRECT;
 435         }
 436         if (tb[TCA_BPF_FLAGS_GEN]) {
 437                 gen_flags = nla_get_u32(tb[TCA_BPF_FLAGS_GEN]);
 438                 if (gen_flags & ~CLS_BPF_SUPPORTED_GEN_FLAGS ||
 439                     !tc_flags_valid(gen_flags))
 440                         return -EINVAL;
 441         }
 442
 443         prog->exts_integrated = have_exts;
 444         prog->gen_flags = gen_flags;
 445
 446         ret = is_bpf ? cls_bpf_prog_from_ops(tb, prog) :
 447                        cls_bpf_prog_from_efd(tb, prog, gen_flags, tp);
 448         if (ret < 0)
 449                 return ret;
 450
 451         if (tb[TCA_BPF_CLASSID]) {
 452                 prog->res.classid = nla_get_u32(tb[TCA_BPF_CLASSID]);
 453                 tcf_bind_filter(tp, &prog->res, base);
 454         }
 455
 456         return 0;
 457 }
 458
 459 static int cls_bpf_change(struct net *net, struct sk_buff *in_skb,
 460                           struct tcf_proto *tp, unsigned long base,
 461                           u32 handle, struct nlattr **tca,
 462                           void **arg, u32 flags,
 463                           struct netlink_ext_ack *extack)
 464 {
 465         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 466         struct cls_bpf_prog *oldprog = *arg;
 467         struct nlattr *tb[TCA_BPF_MAX + 1];
 468         struct cls_bpf_prog *prog;
 469         int ret;
 470
 471         if (tca[TCA_OPTIONS] == NULL)
 472                 return -EINVAL;
 473
 474         ret = nla_parse_nested_deprecated(tb, TCA_BPF_MAX, tca[TCA_OPTIONS],
 475                                           bpf_policy, NULL);
 476         if (ret < 0)
 477                 return ret;
 478
 479         prog = kzalloc(sizeof(*prog), GFP_KERNEL);
 480         if (!prog)
 481                 return -ENOBUFS;
 482
 483         ret = tcf_exts_init(&prog->exts, net, TCA_BPF_ACT, TCA_BPF_POLICE);
 484         if (ret < 0)
 485                 goto errout;
 486
 487         if (oldprog) {
 488                 if (handle && oldprog->handle != handle) {
 489                         ret = -EINVAL;
 490                         goto errout;
 491                 }
 492         }
 493
 494         if (handle == 0) {
 495                 handle = 1;
 496                 ret = idr_alloc_u32(&head->handle_idr, prog, &handle,
 497                                     INT_MAX, GFP_KERNEL);
 498         } else if (!oldprog) {
 499                 ret = idr_alloc_u32(&head->handle_idr, prog, &handle,
 500                                     handle, GFP_KERNEL);
 501         }
 502
 503         if (ret)
 504                 goto errout;
 505         prog->handle = handle;
 506
 507         ret = cls_bpf_set_parms(net, tp, prog, base, tb, tca[TCA_RATE], flags,
 508                                 extack);
 509         if (ret < 0)
 510                 goto errout_idr;
 511
 512         ret = cls_bpf_offload(tp, prog, oldprog, extack);
 513         if (ret)
 514                 goto errout_parms;
 515
 516         if (!tc_in_hw(prog->gen_flags))
 517                 prog->gen_flags |= TCA_CLS_FLAGS_NOT_IN_HW;
 518
 519         if (oldprog) {
 520                 idr_replace(&head->handle_idr, prog, handle);
 521                 list_replace_rcu(&oldprog->link, &prog->link);
 522                 tcf_unbind_filter(tp, &oldprog->res);
 523                 tcf_exts_get_net(&oldprog->exts);
 524                 tcf_queue_work(&oldprog->rwork, cls_bpf_delete_prog_work);
 525         } else {
 526                 list_add_rcu(&prog->link, &head->plist);
 527         }
 528
 529         *arg = prog;
 530         return 0;
 531
 532 errout_parms:
 533         cls_bpf_free_parms(prog);
 534 errout_idr:
 535         if (!oldprog)
 536                 idr_remove(&head->handle_idr, prog->handle);
 537 errout:
 538         tcf_exts_destroy(&prog->exts);
 539         kfree(prog);
 540         return ret;
 541 }
 542
 543 static int cls_bpf_dump_bpf_info(const struct cls_bpf_prog *prog,
 544                                  struct sk_buff *skb)
 545 {
 546         struct nlattr *nla;
 547
 548         if (nla_put_u16(skb, TCA_BPF_OPS_LEN, prog->bpf_num_ops))
 549                 return -EMSGSIZE;
 550
 551         nla = nla_reserve(skb, TCA_BPF_OPS, prog->bpf_num_ops *
 552                           sizeof(struct sock_filter));
 553         if (nla == NULL)
 554                 return -EMSGSIZE;
 555
 556         memcpy(nla_data(nla), prog->bpf_ops, nla_len(nla));
 557
 558         return 0;
 559 }
 560
 561 static int cls_bpf_dump_ebpf_info(const struct cls_bpf_prog *prog,
 562                                   struct sk_buff *skb)
 563 {
 564         struct nlattr *nla;
 565
 566         if (prog->bpf_name &&
 567             nla_put_string(skb, TCA_BPF_NAME, prog->bpf_name))
 568                 return -EMSGSIZE;
 569
 570         if (nla_put_u32(skb, TCA_BPF_ID, prog->filter->aux->id))
 571                 return -EMSGSIZE;
 572
 573         nla = nla_reserve(skb, TCA_BPF_TAG, sizeof(prog->filter->tag));
 574         if (nla == NULL)
 575                 return -EMSGSIZE;
 576
 577         memcpy(nla_data(nla), prog->filter->tag, nla_len(nla));
 578
 579         return 0;
 580 }
 581
 582 static int cls_bpf_dump(struct net *net, struct tcf_proto *tp, void *fh,
 583                         struct sk_buff *skb, struct tcmsg *tm, bool rtnl_held)
 584 {
 585         struct cls_bpf_prog *prog = fh;
 586         struct nlattr *nest;
 587         u32 bpf_flags = 0;
 588         int ret;
 589
 590         if (prog == NULL)
 591                 return skb->len;
 592
 593         tm->tcm_handle = prog->handle;
 594
 595         cls_bpf_offload_update_stats(tp, prog);
 596
 597         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 598         if (nest == NULL)
 599                 goto nla_put_failure;
 600
 601         if (prog->res.classid &&
 602             nla_put_u32(skb, TCA_BPF_CLASSID, prog->res.classid))
 603                 goto nla_put_failure;
 604
 605         if (cls_bpf_is_ebpf(prog))
 606                 ret = cls_bpf_dump_ebpf_info(prog, skb);
 607         else
 608                 ret = cls_bpf_dump_bpf_info(prog, skb);
 609         if (ret)
 610                 goto nla_put_failure;
 611
 612         if (tcf_exts_dump(skb, &prog->exts) < 0)
 613                 goto nla_put_failure;
 614
 615         if (prog->exts_integrated)
 616                 bpf_flags |= TCA_BPF_FLAG_ACT_DIRECT;
 617         if (bpf_flags && nla_put_u32(skb, TCA_BPF_FLAGS, bpf_flags))
 618                 goto nla_put_failure;
 619         if (prog->gen_flags &&
 620             nla_put_u32(skb, TCA_BPF_FLAGS_GEN, prog->gen_flags))
 621                 goto nla_put_failure;
 622
 623         nla_nest_end(skb, nest);
 624
 625         if (tcf_exts_dump_stats(skb, &prog->exts) < 0)
 626                 goto nla_put_failure;
 627
 628         return skb->len;
 629
 630 nla_put_failure:
 631         nla_nest_cancel(skb, nest);
 632         return -1;
 633 }
 634
 635 static void cls_bpf_bind_class(void *fh, u32 classid, unsigned long cl,
 636                                void *q, unsigned long base)
 637 {
 638         struct cls_bpf_prog *prog = fh;
 639
 640         tc_cls_bind_class(classid, cl, q, &prog->res, base);
 641 }
 642
 643 static void cls_bpf_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 644                          bool rtnl_held)
 645 {
 646         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 647         struct cls_bpf_prog *prog;
 648
 649         list_for_each_entry(prog, &head->plist, link) {
 650                 if (!tc_cls_stats_dump(tp, arg, prog))
 651                         break;
 652         }
 653 }
 654
 655 static int cls_bpf_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
 656                              void *cb_priv, struct netlink_ext_ack *extack)
 657 {
 658         struct cls_bpf_head *head = rtnl_dereference(tp->root);
 659         struct tcf_block *block = tp->chain->block;
 660         struct tc_cls_bpf_offload cls_bpf = {};
 661         struct cls_bpf_prog *prog;
 662         int err;
 663
 664         list_for_each_entry(prog, &head->plist, link) {
 665                 if (tc_skip_hw(prog->gen_flags))
 666                         continue;
 667
 668                 tc_cls_common_offload_init(&cls_bpf.common, tp, prog->gen_flags,
 669                                            extack);
 670                 cls_bpf.command = TC_CLSBPF_OFFLOAD;
 671                 cls_bpf.exts = &prog->exts;
 672                 cls_bpf.prog = add ? prog->filter : NULL;
 673                 cls_bpf.oldprog = add ? NULL : prog->filter;
 674                 cls_bpf.name = prog->bpf_name;
 675                 cls_bpf.exts_integrated = prog->exts_integrated;
 676
 677                 err = tc_setup_cb_reoffload(block, tp, add, cb, TC_SETUP_CLSBPF,
 678                                             &cls_bpf, cb_priv, &prog->gen_flags,
 679                                             &prog->in_hw_count);
 680                 if (err)
 681                         return err;
 682         }
 683
 684         return 0;
 685 }
 686
 687 static struct tcf_proto_ops cls_bpf_ops __read_mostly = {
 688         .kind           =       "bpf",
 689         .owner          =       THIS_MODULE,
 690         .classify       =       cls_bpf_classify,
 691         .init           =       cls_bpf_init,
 692         .destroy        =       cls_bpf_destroy,
 693         .get            =       cls_bpf_get,
 694         .change         =       cls_bpf_change,
 695         .delete         =       cls_bpf_delete,
 696         .walk           =       cls_bpf_walk,
 697         .reoffload      =       cls_bpf_reoffload,
 698         .dump           =       cls_bpf_dump,
 699         .bind_class     =       cls_bpf_bind_class,
 700 };
 701
 702 static int __init cls_bpf_init_mod(void)
 703 {
 704         return register_tcf_proto_ops(&cls_bpf_ops);
 705 }
 706
 707 static void __exit cls_bpf_exit_mod(void)
 708 {
 709         unregister_tcf_proto_ops(&cls_bpf_ops);
 710 }
 711
 712 module_init(cls_bpf_init_mod);
 713 module_exit(cls_bpf_exit_mod);