1 /* 2 * net/sched/cls_flow.c Generic flow classifier 3 * 4 * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 2 9 * of the License, or (at your option) any later version. 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/init.h> 14 #include <linux/list.h> 15 #include <linux/jhash.h> 16 #include <linux/random.h> 17 #include <linux/pkt_cls.h> 18 #include <linux/skbuff.h> 19 #include <linux/in.h> 20 #include <linux/ip.h> 21 #include <linux/ipv6.h> 22 #include <linux/if_vlan.h> 23 #include <linux/slab.h> 24 #include <linux/module.h> 25 #include <net/inet_sock.h> 26 27 #include <net/pkt_cls.h> 28 #include <net/ip.h> 29 #include <net/route.h> 30 #include <net/flow_dissector.h> 31 32 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 33 #include <net/netfilter/nf_conntrack.h> 34 #endif 35 36 struct flow_head { 37 struct list_head filters; 38 struct rcu_head rcu; 39 }; 40 41 struct flow_filter { 42 struct list_head list; 43 struct tcf_exts exts; 44 struct tcf_ematch_tree ematches; 45 struct tcf_proto *tp; 46 struct timer_list perturb_timer; 47 u32 perturb_period; 48 u32 handle; 49 50 u32 nkeys; 51 u32 keymask; 52 u32 mode; 53 u32 mask; 54 u32 xor; 55 u32 rshift; 56 u32 addend; 57 u32 divisor; 58 u32 baseclass; 59 u32 hashrnd; 60 union { 61 struct work_struct work; 62 struct rcu_head rcu; 63 }; 64 }; 65 66 static inline u32 addr_fold(void *addr) 67 { 68 unsigned long a = (unsigned long)addr; 69 70 return (a & 0xFFFFFFFF) ^ (BITS_PER_LONG > 32 ? a >> 32 : 0); 71 } 72 73 static u32 flow_get_src(const struct sk_buff *skb, const struct flow_keys *flow) 74 { 75 __be32 src = flow_get_u32_src(flow); 76 77 if (src) 78 return ntohl(src); 79 80 return addr_fold(skb->sk); 81 } 82 83 static u32 flow_get_dst(const struct sk_buff *skb, const struct flow_keys *flow) 84 { 85 __be32 dst = flow_get_u32_dst(flow); 86 87 if (dst) 88 return ntohl(dst); 89 90 return addr_fold(skb_dst(skb)) ^ (__force u16) tc_skb_protocol(skb); 91 } 92 93 static u32 flow_get_proto(const struct sk_buff *skb, 94 const struct flow_keys *flow) 95 { 96 return flow->basic.ip_proto; 97 } 98 99 static u32 flow_get_proto_src(const struct sk_buff *skb, 100 const struct flow_keys *flow) 101 { 102 if (flow->ports.ports) 103 return ntohs(flow->ports.src); 104 105 return addr_fold(skb->sk); 106 } 107 108 static u32 flow_get_proto_dst(const struct sk_buff *skb, 109 const struct flow_keys *flow) 110 { 111 if (flow->ports.ports) 112 return ntohs(flow->ports.dst); 113 114 return addr_fold(skb_dst(skb)) ^ (__force u16) tc_skb_protocol(skb); 115 } 116 117 static u32 flow_get_iif(const struct sk_buff *skb) 118 { 119 return skb->skb_iif; 120 } 121 122 static u32 flow_get_priority(const struct sk_buff *skb) 123 { 124 return skb->priority; 125 } 126 127 static u32 flow_get_mark(const struct sk_buff *skb) 128 { 129 return skb->mark; 130 } 131 132 static u32 flow_get_nfct(const struct sk_buff *skb) 133 { 134 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 135 return addr_fold(skb_nfct(skb)); 136 #else 137 return 0; 138 #endif 139 } 140 141 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 142 #define CTTUPLE(skb, member) \ 143 ({ \ 144 enum ip_conntrack_info ctinfo; \ 145 const struct nf_conn *ct = nf_ct_get(skb, &ctinfo); \ 146 if (ct == NULL) \ 147 goto fallback; \ 148 ct->tuplehash[CTINFO2DIR(ctinfo)].tuple.member; \ 149 }) 150 #else 151 #define CTTUPLE(skb, member) \ 152 ({ \ 153 goto fallback; \ 154 0; \ 155 }) 156 #endif 157 158 static u32 flow_get_nfct_src(const struct sk_buff *skb, 159 const struct flow_keys *flow) 160 { 161 switch (tc_skb_protocol(skb)) { 162 case htons(ETH_P_IP): 163 return ntohl(CTTUPLE(skb, src.u3.ip)); 164 case htons(ETH_P_IPV6): 165 return ntohl(CTTUPLE(skb, src.u3.ip6[3])); 166 } 167 fallback: 168 return flow_get_src(skb, flow); 169 } 170 171 static u32 flow_get_nfct_dst(const struct sk_buff *skb, 172 const struct flow_keys *flow) 173 { 174 switch (tc_skb_protocol(skb)) { 175 case htons(ETH_P_IP): 176 return ntohl(CTTUPLE(skb, dst.u3.ip)); 177 case htons(ETH_P_IPV6): 178 return ntohl(CTTUPLE(skb, dst.u3.ip6[3])); 179 } 180 fallback: 181 return flow_get_dst(skb, flow); 182 } 183 184 static u32 flow_get_nfct_proto_src(const struct sk_buff *skb, 185 const struct flow_keys *flow) 186 { 187 return ntohs(CTTUPLE(skb, src.u.all)); 188 fallback: 189 return flow_get_proto_src(skb, flow); 190 } 191 192 static u32 flow_get_nfct_proto_dst(const struct sk_buff *skb, 193 const struct flow_keys *flow) 194 { 195 return ntohs(CTTUPLE(skb, dst.u.all)); 196 fallback: 197 return flow_get_proto_dst(skb, flow); 198 } 199 200 static u32 flow_get_rtclassid(const struct sk_buff *skb) 201 { 202 #ifdef CONFIG_IP_ROUTE_CLASSID 203 if (skb_dst(skb)) 204 return skb_dst(skb)->tclassid; 205 #endif 206 return 0; 207 } 208 209 static u32 flow_get_skuid(const struct sk_buff *skb) 210 { 211 struct sock *sk = skb_to_full_sk(skb); 212 213 if (sk && sk->sk_socket && sk->sk_socket->file) { 214 kuid_t skuid = sk->sk_socket->file->f_cred->fsuid; 215 216 return from_kuid(&init_user_ns, skuid); 217 } 218 return 0; 219 } 220 221 static u32 flow_get_skgid(const struct sk_buff *skb) 222 { 223 struct sock *sk = skb_to_full_sk(skb); 224 225 if (sk && sk->sk_socket && sk->sk_socket->file) { 226 kgid_t skgid = sk->sk_socket->file->f_cred->fsgid; 227 228 return from_kgid(&init_user_ns, skgid); 229 } 230 return 0; 231 } 232 233 static u32 flow_get_vlan_tag(const struct sk_buff *skb) 234 { 235 u16 uninitialized_var(tag); 236 237 if (vlan_get_tag(skb, &tag) < 0) 238 return 0; 239 return tag & VLAN_VID_MASK; 240 } 241 242 static u32 flow_get_rxhash(struct sk_buff *skb) 243 { 244 return skb_get_hash(skb); 245 } 246 247 static u32 flow_key_get(struct sk_buff *skb, int key, struct flow_keys *flow) 248 { 249 switch (key) { 250 case FLOW_KEY_SRC: 251 return flow_get_src(skb, flow); 252 case FLOW_KEY_DST: 253 return flow_get_dst(skb, flow); 254 case FLOW_KEY_PROTO: 255 return flow_get_proto(skb, flow); 256 case FLOW_KEY_PROTO_SRC: 257 return flow_get_proto_src(skb, flow); 258 case FLOW_KEY_PROTO_DST: 259 return flow_get_proto_dst(skb, flow); 260 case FLOW_KEY_IIF: 261 return flow_get_iif(skb); 262 case FLOW_KEY_PRIORITY: 263 return flow_get_priority(skb); 264 case FLOW_KEY_MARK: 265 return flow_get_mark(skb); 266 case FLOW_KEY_NFCT: 267 return flow_get_nfct(skb); 268 case FLOW_KEY_NFCT_SRC: 269 return flow_get_nfct_src(skb, flow); 270 case FLOW_KEY_NFCT_DST: 271 return flow_get_nfct_dst(skb, flow); 272 case FLOW_KEY_NFCT_PROTO_SRC: 273 return flow_get_nfct_proto_src(skb, flow); 274 case FLOW_KEY_NFCT_PROTO_DST: 275 return flow_get_nfct_proto_dst(skb, flow); 276 case FLOW_KEY_RTCLASSID: 277 return flow_get_rtclassid(skb); 278 case FLOW_KEY_SKUID: 279 return flow_get_skuid(skb); 280 case FLOW_KEY_SKGID: 281 return flow_get_skgid(skb); 282 case FLOW_KEY_VLAN_TAG: 283 return flow_get_vlan_tag(skb); 284 case FLOW_KEY_RXHASH: 285 return flow_get_rxhash(skb); 286 default: 287 WARN_ON(1); 288 return 0; 289 } 290 } 291 292 #define FLOW_KEYS_NEEDED ((1 << FLOW_KEY_SRC) | \ 293 (1 << FLOW_KEY_DST) | \ 294 (1 << FLOW_KEY_PROTO) | \ 295 (1 << FLOW_KEY_PROTO_SRC) | \ 296 (1 << FLOW_KEY_PROTO_DST) | \ 297 (1 << FLOW_KEY_NFCT_SRC) | \ 298 (1 << FLOW_KEY_NFCT_DST) | \ 299 (1 << FLOW_KEY_NFCT_PROTO_SRC) | \ 300 (1 << FLOW_KEY_NFCT_PROTO_DST)) 301 302 static int flow_classify(struct sk_buff *skb, const struct tcf_proto *tp, 303 struct tcf_result *res) 304 { 305 struct flow_head *head = rcu_dereference_bh(tp->root); 306 struct flow_filter *f; 307 u32 keymask; 308 u32 classid; 309 unsigned int n, key; 310 int r; 311 312 list_for_each_entry_rcu(f, &head->filters, list) { 313 u32 keys[FLOW_KEY_MAX + 1]; 314 struct flow_keys flow_keys; 315 316 if (!tcf_em_tree_match(skb, &f->ematches, NULL)) 317 continue; 318 319 keymask = f->keymask; 320 if (keymask & FLOW_KEYS_NEEDED) 321 skb_flow_dissect_flow_keys(skb, &flow_keys, 0); 322 323 for (n = 0; n < f->nkeys; n++) { 324 key = ffs(keymask) - 1; 325 keymask &= ~(1 << key); 326 keys[n] = flow_key_get(skb, key, &flow_keys); 327 } 328 329 if (f->mode == FLOW_MODE_HASH) 330 classid = jhash2(keys, f->nkeys, f->hashrnd); 331 else { 332 classid = keys[0]; 333 classid = (classid & f->mask) ^ f->xor; 334 classid = (classid >> f->rshift) + f->addend; 335 } 336 337 if (f->divisor) 338 classid %= f->divisor; 339 340 res->class = 0; 341 res->classid = TC_H_MAKE(f->baseclass, f->baseclass + classid); 342 343 r = tcf_exts_exec(skb, &f->exts, res); 344 if (r < 0) 345 continue; 346 return r; 347 } 348 return -1; 349 } 350 351 static void flow_perturbation(struct timer_list *t) 352 { 353 struct flow_filter *f = from_timer(f, t, perturb_timer); 354 355 get_random_bytes(&f->hashrnd, 4); 356 if (f->perturb_period) 357 mod_timer(&f->perturb_timer, jiffies + f->perturb_period); 358 } 359 360 static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = { 361 [TCA_FLOW_KEYS] = { .type = NLA_U32 }, 362 [TCA_FLOW_MODE] = { .type = NLA_U32 }, 363 [TCA_FLOW_BASECLASS] = { .type = NLA_U32 }, 364 [TCA_FLOW_RSHIFT] = { .type = NLA_U32 }, 365 [TCA_FLOW_ADDEND] = { .type = NLA_U32 }, 366 [TCA_FLOW_MASK] = { .type = NLA_U32 }, 367 [TCA_FLOW_XOR] = { .type = NLA_U32 }, 368 [TCA_FLOW_DIVISOR] = { .type = NLA_U32 }, 369 [TCA_FLOW_ACT] = { .type = NLA_NESTED }, 370 [TCA_FLOW_POLICE] = { .type = NLA_NESTED }, 371 [TCA_FLOW_EMATCHES] = { .type = NLA_NESTED }, 372 [TCA_FLOW_PERTURB] = { .type = NLA_U32 }, 373 }; 374 375 static void flow_destroy_filter_work(struct work_struct *work) 376 { 377 struct flow_filter *f = container_of(work, struct flow_filter, work); 378 379 rtnl_lock(); 380 del_timer_sync(&f->perturb_timer); 381 tcf_exts_destroy(&f->exts); 382 tcf_em_tree_destroy(&f->ematches); 383 kfree(f); 384 rtnl_unlock(); 385 } 386 387 static void flow_destroy_filter(struct rcu_head *head) 388 { 389 struct flow_filter *f = container_of(head, struct flow_filter, rcu); 390 391 INIT_WORK(&f->work, flow_destroy_filter_work); 392 tcf_queue_work(&f->work); 393 } 394 395 static int flow_change(struct net *net, struct sk_buff *in_skb, 396 struct tcf_proto *tp, unsigned long base, 397 u32 handle, struct nlattr **tca, 398 void **arg, bool ovr) 399 { 400 struct flow_head *head = rtnl_dereference(tp->root); 401 struct flow_filter *fold, *fnew; 402 struct nlattr *opt = tca[TCA_OPTIONS]; 403 struct nlattr *tb[TCA_FLOW_MAX + 1]; 404 unsigned int nkeys = 0; 405 unsigned int perturb_period = 0; 406 u32 baseclass = 0; 407 u32 keymask = 0; 408 u32 mode; 409 int err; 410 411 if (opt == NULL) 412 return -EINVAL; 413 414 err = nla_parse_nested(tb, TCA_FLOW_MAX, opt, flow_policy, NULL); 415 if (err < 0) 416 return err; 417 418 if (tb[TCA_FLOW_BASECLASS]) { 419 baseclass = nla_get_u32(tb[TCA_FLOW_BASECLASS]); 420 if (TC_H_MIN(baseclass) == 0) 421 return -EINVAL; 422 } 423 424 if (tb[TCA_FLOW_KEYS]) { 425 keymask = nla_get_u32(tb[TCA_FLOW_KEYS]); 426 427 nkeys = hweight32(keymask); 428 if (nkeys == 0) 429 return -EINVAL; 430 431 if (fls(keymask) - 1 > FLOW_KEY_MAX) 432 return -EOPNOTSUPP; 433 434 if ((keymask & (FLOW_KEY_SKUID|FLOW_KEY_SKGID)) && 435 sk_user_ns(NETLINK_CB(in_skb).sk) != &init_user_ns) 436 return -EOPNOTSUPP; 437 } 438 439 fnew = kzalloc(sizeof(*fnew), GFP_KERNEL); 440 if (!fnew) 441 return -ENOBUFS; 442 443 err = tcf_em_tree_validate(tp, tb[TCA_FLOW_EMATCHES], &fnew->ematches); 444 if (err < 0) 445 goto err1; 446 447 err = tcf_exts_init(&fnew->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE); 448 if (err < 0) 449 goto err2; 450 451 err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &fnew->exts, ovr); 452 if (err < 0) 453 goto err2; 454 455 fold = *arg; 456 if (fold) { 457 err = -EINVAL; 458 if (fold->handle != handle && handle) 459 goto err2; 460 461 /* Copy fold into fnew */ 462 fnew->tp = fold->tp; 463 fnew->handle = fold->handle; 464 fnew->nkeys = fold->nkeys; 465 fnew->keymask = fold->keymask; 466 fnew->mode = fold->mode; 467 fnew->mask = fold->mask; 468 fnew->xor = fold->xor; 469 fnew->rshift = fold->rshift; 470 fnew->addend = fold->addend; 471 fnew->divisor = fold->divisor; 472 fnew->baseclass = fold->baseclass; 473 fnew->hashrnd = fold->hashrnd; 474 475 mode = fold->mode; 476 if (tb[TCA_FLOW_MODE]) 477 mode = nla_get_u32(tb[TCA_FLOW_MODE]); 478 if (mode != FLOW_MODE_HASH && nkeys > 1) 479 goto err2; 480 481 if (mode == FLOW_MODE_HASH) 482 perturb_period = fold->perturb_period; 483 if (tb[TCA_FLOW_PERTURB]) { 484 if (mode != FLOW_MODE_HASH) 485 goto err2; 486 perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ; 487 } 488 } else { 489 err = -EINVAL; 490 if (!handle) 491 goto err2; 492 if (!tb[TCA_FLOW_KEYS]) 493 goto err2; 494 495 mode = FLOW_MODE_MAP; 496 if (tb[TCA_FLOW_MODE]) 497 mode = nla_get_u32(tb[TCA_FLOW_MODE]); 498 if (mode != FLOW_MODE_HASH && nkeys > 1) 499 goto err2; 500 501 if (tb[TCA_FLOW_PERTURB]) { 502 if (mode != FLOW_MODE_HASH) 503 goto err2; 504 perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ; 505 } 506 507 if (TC_H_MAJ(baseclass) == 0) { 508 struct Qdisc *q = tcf_block_q(tp->chain->block); 509 510 baseclass = TC_H_MAKE(q->handle, baseclass); 511 } 512 if (TC_H_MIN(baseclass) == 0) 513 baseclass = TC_H_MAKE(baseclass, 1); 514 515 fnew->handle = handle; 516 fnew->mask = ~0U; 517 fnew->tp = tp; 518 get_random_bytes(&fnew->hashrnd, 4); 519 } 520 521 timer_setup(&fnew->perturb_timer, flow_perturbation, TIMER_DEFERRABLE); 522 523 netif_keep_dst(qdisc_dev(tp->q)); 524 525 if (tb[TCA_FLOW_KEYS]) { 526 fnew->keymask = keymask; 527 fnew->nkeys = nkeys; 528 } 529 530 fnew->mode = mode; 531 532 if (tb[TCA_FLOW_MASK]) 533 fnew->mask = nla_get_u32(tb[TCA_FLOW_MASK]); 534 if (tb[TCA_FLOW_XOR]) 535 fnew->xor = nla_get_u32(tb[TCA_FLOW_XOR]); 536 if (tb[TCA_FLOW_RSHIFT]) 537 fnew->rshift = nla_get_u32(tb[TCA_FLOW_RSHIFT]); 538 if (tb[TCA_FLOW_ADDEND]) 539 fnew->addend = nla_get_u32(tb[TCA_FLOW_ADDEND]); 540 541 if (tb[TCA_FLOW_DIVISOR]) 542 fnew->divisor = nla_get_u32(tb[TCA_FLOW_DIVISOR]); 543 if (baseclass) 544 fnew->baseclass = baseclass; 545 546 fnew->perturb_period = perturb_period; 547 if (perturb_period) 548 mod_timer(&fnew->perturb_timer, jiffies + perturb_period); 549 550 if (!*arg) 551 list_add_tail_rcu(&fnew->list, &head->filters); 552 else 553 list_replace_rcu(&fold->list, &fnew->list); 554 555 *arg = fnew; 556 557 if (fold) 558 call_rcu(&fold->rcu, flow_destroy_filter); 559 return 0; 560 561 err2: 562 tcf_exts_destroy(&fnew->exts); 563 tcf_em_tree_destroy(&fnew->ematches); 564 err1: 565 kfree(fnew); 566 return err; 567 } 568 569 static int flow_delete(struct tcf_proto *tp, void *arg, bool *last) 570 { 571 struct flow_head *head = rtnl_dereference(tp->root); 572 struct flow_filter *f = arg; 573 574 list_del_rcu(&f->list); 575 call_rcu(&f->rcu, flow_destroy_filter); 576 *last = list_empty(&head->filters); 577 return 0; 578 } 579 580 static int flow_init(struct tcf_proto *tp) 581 { 582 struct flow_head *head; 583 584 head = kzalloc(sizeof(*head), GFP_KERNEL); 585 if (head == NULL) 586 return -ENOBUFS; 587 INIT_LIST_HEAD(&head->filters); 588 rcu_assign_pointer(tp->root, head); 589 return 0; 590 } 591 592 static void flow_destroy(struct tcf_proto *tp) 593 { 594 struct flow_head *head = rtnl_dereference(tp->root); 595 struct flow_filter *f, *next; 596 597 list_for_each_entry_safe(f, next, &head->filters, list) { 598 list_del_rcu(&f->list); 599 call_rcu(&f->rcu, flow_destroy_filter); 600 } 601 kfree_rcu(head, rcu); 602 } 603 604 static void *flow_get(struct tcf_proto *tp, u32 handle) 605 { 606 struct flow_head *head = rtnl_dereference(tp->root); 607 struct flow_filter *f; 608 609 list_for_each_entry(f, &head->filters, list) 610 if (f->handle == handle) 611 return f; 612 return NULL; 613 } 614 615 static int flow_dump(struct net *net, struct tcf_proto *tp, void *fh, 616 struct sk_buff *skb, struct tcmsg *t) 617 { 618 struct flow_filter *f = fh; 619 struct nlattr *nest; 620 621 if (f == NULL) 622 return skb->len; 623 624 t->tcm_handle = f->handle; 625 626 nest = nla_nest_start(skb, TCA_OPTIONS); 627 if (nest == NULL) 628 goto nla_put_failure; 629 630 if (nla_put_u32(skb, TCA_FLOW_KEYS, f->keymask) || 631 nla_put_u32(skb, TCA_FLOW_MODE, f->mode)) 632 goto nla_put_failure; 633 634 if (f->mask != ~0 || f->xor != 0) { 635 if (nla_put_u32(skb, TCA_FLOW_MASK, f->mask) || 636 nla_put_u32(skb, TCA_FLOW_XOR, f->xor)) 637 goto nla_put_failure; 638 } 639 if (f->rshift && 640 nla_put_u32(skb, TCA_FLOW_RSHIFT, f->rshift)) 641 goto nla_put_failure; 642 if (f->addend && 643 nla_put_u32(skb, TCA_FLOW_ADDEND, f->addend)) 644 goto nla_put_failure; 645 646 if (f->divisor && 647 nla_put_u32(skb, TCA_FLOW_DIVISOR, f->divisor)) 648 goto nla_put_failure; 649 if (f->baseclass && 650 nla_put_u32(skb, TCA_FLOW_BASECLASS, f->baseclass)) 651 goto nla_put_failure; 652 653 if (f->perturb_period && 654 nla_put_u32(skb, TCA_FLOW_PERTURB, f->perturb_period / HZ)) 655 goto nla_put_failure; 656 657 if (tcf_exts_dump(skb, &f->exts) < 0) 658 goto nla_put_failure; 659 #ifdef CONFIG_NET_EMATCH 660 if (f->ematches.hdr.nmatches && 661 tcf_em_tree_dump(skb, &f->ematches, TCA_FLOW_EMATCHES) < 0) 662 goto nla_put_failure; 663 #endif 664 nla_nest_end(skb, nest); 665 666 if (tcf_exts_dump_stats(skb, &f->exts) < 0) 667 goto nla_put_failure; 668 669 return skb->len; 670 671 nla_put_failure: 672 nla_nest_cancel(skb, nest); 673 return -1; 674 } 675 676 static void flow_walk(struct tcf_proto *tp, struct tcf_walker *arg) 677 { 678 struct flow_head *head = rtnl_dereference(tp->root); 679 struct flow_filter *f; 680 681 list_for_each_entry(f, &head->filters, list) { 682 if (arg->count < arg->skip) 683 goto skip; 684 if (arg->fn(tp, f, arg) < 0) { 685 arg->stop = 1; 686 break; 687 } 688 skip: 689 arg->count++; 690 } 691 } 692 693 static struct tcf_proto_ops cls_flow_ops __read_mostly = { 694 .kind = "flow", 695 .classify = flow_classify, 696 .init = flow_init, 697 .destroy = flow_destroy, 698 .change = flow_change, 699 .delete = flow_delete, 700 .get = flow_get, 701 .dump = flow_dump, 702 .walk = flow_walk, 703 .owner = THIS_MODULE, 704 }; 705 706 static int __init cls_flow_init(void) 707 { 708 return register_tcf_proto_ops(&cls_flow_ops); 709 } 710 711 static void __exit cls_flow_exit(void) 712 { 713 unregister_tcf_proto_ops(&cls_flow_ops); 714 } 715 716 module_init(cls_flow_init); 717 module_exit(cls_flow_exit); 718 719 MODULE_LICENSE("GPL"); 720 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); 721 MODULE_DESCRIPTION("TC flow classifier"); 722