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