xref: /openbmc/linux/net/sched/cls_flow.c (revision 7dd65feb) 
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 
24 #include <net/pkt_cls.h>
25 #include <net/ip.h>
26 #include <net/route.h>
27 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
28 #include <net/netfilter/nf_conntrack.h>
29 #endif
30 
31 struct flow_head {
32 	struct list_head	filters;
33 };
34 
35 struct flow_filter {
36 	struct list_head	list;
37 	struct tcf_exts		exts;
38 	struct tcf_ematch_tree	ematches;
39 	struct timer_list	perturb_timer;
40 	u32			perturb_period;
41 	u32			handle;
42 
43 	u32			nkeys;
44 	u32			keymask;
45 	u32			mode;
46 	u32			mask;
47 	u32			xor;
48 	u32			rshift;
49 	u32			addend;
50 	u32			divisor;
51 	u32			baseclass;
52 	u32			hashrnd;
53 };
54 
55 static const struct tcf_ext_map flow_ext_map = {
56 	.action	= TCA_FLOW_ACT,
57 	.police	= TCA_FLOW_POLICE,
58 };
59 
60 static inline u32 addr_fold(void *addr)
61 {
62 	unsigned long a = (unsigned long)addr;
63 
64 	return (a & 0xFFFFFFFF) ^ (BITS_PER_LONG > 32 ? a >> 32 : 0);
65 }
66 
67 static u32 flow_get_src(const struct sk_buff *skb)
68 {
69 	switch (skb->protocol) {
70 	case htons(ETH_P_IP):
71 		return ntohl(ip_hdr(skb)->saddr);
72 	case htons(ETH_P_IPV6):
73 		return ntohl(ipv6_hdr(skb)->saddr.s6_addr32[3]);
74 	default:
75 		return addr_fold(skb->sk);
76 	}
77 }
78 
79 static u32 flow_get_dst(const struct sk_buff *skb)
80 {
81 	switch (skb->protocol) {
82 	case htons(ETH_P_IP):
83 		return ntohl(ip_hdr(skb)->daddr);
84 	case htons(ETH_P_IPV6):
85 		return ntohl(ipv6_hdr(skb)->daddr.s6_addr32[3]);
86 	default:
87 		return addr_fold(skb_dst(skb)) ^ (__force u16)skb->protocol;
88 	}
89 }
90 
91 static u32 flow_get_proto(const struct sk_buff *skb)
92 {
93 	switch (skb->protocol) {
94 	case htons(ETH_P_IP):
95 		return ip_hdr(skb)->protocol;
96 	case htons(ETH_P_IPV6):
97 		return ipv6_hdr(skb)->nexthdr;
98 	default:
99 		return 0;
100 	}
101 }
102 
103 static int has_ports(u8 protocol)
104 {
105 	switch (protocol) {
106 	case IPPROTO_TCP:
107 	case IPPROTO_UDP:
108 	case IPPROTO_UDPLITE:
109 	case IPPROTO_SCTP:
110 	case IPPROTO_DCCP:
111 	case IPPROTO_ESP:
112 		return 1;
113 	default:
114 		return 0;
115 	}
116 }
117 
118 static u32 flow_get_proto_src(const struct sk_buff *skb)
119 {
120 	u32 res = 0;
121 
122 	switch (skb->protocol) {
123 	case htons(ETH_P_IP): {
124 		struct iphdr *iph = ip_hdr(skb);
125 
126 		if (!(iph->frag_off&htons(IP_MF|IP_OFFSET)) &&
127 		    has_ports(iph->protocol))
128 			res = ntohs(*(__be16 *)((void *)iph + iph->ihl * 4));
129 		break;
130 	}
131 	case htons(ETH_P_IPV6): {
132 		struct ipv6hdr *iph = ipv6_hdr(skb);
133 
134 		if (has_ports(iph->nexthdr))
135 			res = ntohs(*(__be16 *)&iph[1]);
136 		break;
137 	}
138 	default:
139 		res = addr_fold(skb->sk);
140 	}
141 
142 	return res;
143 }
144 
145 static u32 flow_get_proto_dst(const struct sk_buff *skb)
146 {
147 	u32 res = 0;
148 
149 	switch (skb->protocol) {
150 	case htons(ETH_P_IP): {
151 		struct iphdr *iph = ip_hdr(skb);
152 
153 		if (!(iph->frag_off&htons(IP_MF|IP_OFFSET)) &&
154 		    has_ports(iph->protocol))
155 			res = ntohs(*(__be16 *)((void *)iph + iph->ihl * 4 + 2));
156 		break;
157 	}
158 	case htons(ETH_P_IPV6): {
159 		struct ipv6hdr *iph = ipv6_hdr(skb);
160 
161 		if (has_ports(iph->nexthdr))
162 			res = ntohs(*(__be16 *)((void *)&iph[1] + 2));
163 		break;
164 	}
165 	default:
166 		res = addr_fold(skb_dst(skb)) ^ (__force u16)skb->protocol;
167 	}
168 
169 	return res;
170 }
171 
172 static u32 flow_get_iif(const struct sk_buff *skb)
173 {
174 	return skb->skb_iif;
175 }
176 
177 static u32 flow_get_priority(const struct sk_buff *skb)
178 {
179 	return skb->priority;
180 }
181 
182 static u32 flow_get_mark(const struct sk_buff *skb)
183 {
184 	return skb->mark;
185 }
186 
187 static u32 flow_get_nfct(const struct sk_buff *skb)
188 {
189 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
190 	return addr_fold(skb->nfct);
191 #else
192 	return 0;
193 #endif
194 }
195 
196 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
197 #define CTTUPLE(skb, member)						\
198 ({									\
199 	enum ip_conntrack_info ctinfo;					\
200 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);			\
201 	if (ct == NULL)							\
202 		goto fallback;						\
203 	ct->tuplehash[CTINFO2DIR(ctinfo)].tuple.member;			\
204 })
205 #else
206 #define CTTUPLE(skb, member)						\
207 ({									\
208 	goto fallback;							\
209 	0;								\
210 })
211 #endif
212 
213 static u32 flow_get_nfct_src(const struct sk_buff *skb)
214 {
215 	switch (skb->protocol) {
216 	case htons(ETH_P_IP):
217 		return ntohl(CTTUPLE(skb, src.u3.ip));
218 	case htons(ETH_P_IPV6):
219 		return ntohl(CTTUPLE(skb, src.u3.ip6[3]));
220 	}
221 fallback:
222 	return flow_get_src(skb);
223 }
224 
225 static u32 flow_get_nfct_dst(const struct sk_buff *skb)
226 {
227 	switch (skb->protocol) {
228 	case htons(ETH_P_IP):
229 		return ntohl(CTTUPLE(skb, dst.u3.ip));
230 	case htons(ETH_P_IPV6):
231 		return ntohl(CTTUPLE(skb, dst.u3.ip6[3]));
232 	}
233 fallback:
234 	return flow_get_dst(skb);
235 }
236 
237 static u32 flow_get_nfct_proto_src(const struct sk_buff *skb)
238 {
239 	return ntohs(CTTUPLE(skb, src.u.all));
240 fallback:
241 	return flow_get_proto_src(skb);
242 }
243 
244 static u32 flow_get_nfct_proto_dst(const struct sk_buff *skb)
245 {
246 	return ntohs(CTTUPLE(skb, dst.u.all));
247 fallback:
248 	return flow_get_proto_dst(skb);
249 }
250 
251 static u32 flow_get_rtclassid(const struct sk_buff *skb)
252 {
253 #ifdef CONFIG_NET_CLS_ROUTE
254 	if (skb_dst(skb))
255 		return skb_dst(skb)->tclassid;
256 #endif
257 	return 0;
258 }
259 
260 static u32 flow_get_skuid(const struct sk_buff *skb)
261 {
262 	if (skb->sk && skb->sk->sk_socket && skb->sk->sk_socket->file)
263 		return skb->sk->sk_socket->file->f_cred->fsuid;
264 	return 0;
265 }
266 
267 static u32 flow_get_skgid(const struct sk_buff *skb)
268 {
269 	if (skb->sk && skb->sk->sk_socket && skb->sk->sk_socket->file)
270 		return skb->sk->sk_socket->file->f_cred->fsgid;
271 	return 0;
272 }
273 
274 static u32 flow_get_vlan_tag(const struct sk_buff *skb)
275 {
276 	u16 uninitialized_var(tag);
277 
278 	if (vlan_get_tag(skb, &tag) < 0)
279 		return 0;
280 	return tag & VLAN_VID_MASK;
281 }
282 
283 static u32 flow_key_get(const struct sk_buff *skb, int key)
284 {
285 	switch (key) {
286 	case FLOW_KEY_SRC:
287 		return flow_get_src(skb);
288 	case FLOW_KEY_DST:
289 		return flow_get_dst(skb);
290 	case FLOW_KEY_PROTO:
291 		return flow_get_proto(skb);
292 	case FLOW_KEY_PROTO_SRC:
293 		return flow_get_proto_src(skb);
294 	case FLOW_KEY_PROTO_DST:
295 		return flow_get_proto_dst(skb);
296 	case FLOW_KEY_IIF:
297 		return flow_get_iif(skb);
298 	case FLOW_KEY_PRIORITY:
299 		return flow_get_priority(skb);
300 	case FLOW_KEY_MARK:
301 		return flow_get_mark(skb);
302 	case FLOW_KEY_NFCT:
303 		return flow_get_nfct(skb);
304 	case FLOW_KEY_NFCT_SRC:
305 		return flow_get_nfct_src(skb);
306 	case FLOW_KEY_NFCT_DST:
307 		return flow_get_nfct_dst(skb);
308 	case FLOW_KEY_NFCT_PROTO_SRC:
309 		return flow_get_nfct_proto_src(skb);
310 	case FLOW_KEY_NFCT_PROTO_DST:
311 		return flow_get_nfct_proto_dst(skb);
312 	case FLOW_KEY_RTCLASSID:
313 		return flow_get_rtclassid(skb);
314 	case FLOW_KEY_SKUID:
315 		return flow_get_skuid(skb);
316 	case FLOW_KEY_SKGID:
317 		return flow_get_skgid(skb);
318 	case FLOW_KEY_VLAN_TAG:
319 		return flow_get_vlan_tag(skb);
320 	default:
321 		WARN_ON(1);
322 		return 0;
323 	}
324 }
325 
326 static int flow_classify(struct sk_buff *skb, struct tcf_proto *tp,
327 			 struct tcf_result *res)
328 {
329 	struct flow_head *head = tp->root;
330 	struct flow_filter *f;
331 	u32 keymask;
332 	u32 classid;
333 	unsigned int n, key;
334 	int r;
335 
336 	list_for_each_entry(f, &head->filters, list) {
337 		u32 keys[f->nkeys];
338 
339 		if (!tcf_em_tree_match(skb, &f->ematches, NULL))
340 			continue;
341 
342 		keymask = f->keymask;
343 
344 		for (n = 0; n < f->nkeys; n++) {
345 			key = ffs(keymask) - 1;
346 			keymask &= ~(1 << key);
347 			keys[n] = flow_key_get(skb, key);
348 		}
349 
350 		if (f->mode == FLOW_MODE_HASH)
351 			classid = jhash2(keys, f->nkeys, f->hashrnd);
352 		else {
353 			classid = keys[0];
354 			classid = (classid & f->mask) ^ f->xor;
355 			classid = (classid >> f->rshift) + f->addend;
356 		}
357 
358 		if (f->divisor)
359 			classid %= f->divisor;
360 
361 		res->class   = 0;
362 		res->classid = TC_H_MAKE(f->baseclass, f->baseclass + classid);
363 
364 		r = tcf_exts_exec(skb, &f->exts, res);
365 		if (r < 0)
366 			continue;
367 		return r;
368 	}
369 	return -1;
370 }
371 
372 static void flow_perturbation(unsigned long arg)
373 {
374 	struct flow_filter *f = (struct flow_filter *)arg;
375 
376 	get_random_bytes(&f->hashrnd, 4);
377 	if (f->perturb_period)
378 		mod_timer(&f->perturb_timer, jiffies + f->perturb_period);
379 }
380 
381 static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = {
382 	[TCA_FLOW_KEYS]		= { .type = NLA_U32 },
383 	[TCA_FLOW_MODE]		= { .type = NLA_U32 },
384 	[TCA_FLOW_BASECLASS]	= { .type = NLA_U32 },
385 	[TCA_FLOW_RSHIFT]	= { .type = NLA_U32 },
386 	[TCA_FLOW_ADDEND]	= { .type = NLA_U32 },
387 	[TCA_FLOW_MASK]		= { .type = NLA_U32 },
388 	[TCA_FLOW_XOR]		= { .type = NLA_U32 },
389 	[TCA_FLOW_DIVISOR]	= { .type = NLA_U32 },
390 	[TCA_FLOW_ACT]		= { .type = NLA_NESTED },
391 	[TCA_FLOW_POLICE]	= { .type = NLA_NESTED },
392 	[TCA_FLOW_EMATCHES]	= { .type = NLA_NESTED },
393 	[TCA_FLOW_PERTURB]	= { .type = NLA_U32 },
394 };
395 
396 static int flow_change(struct tcf_proto *tp, unsigned long base,
397 		       u32 handle, struct nlattr **tca,
398 		       unsigned long *arg)
399 {
400 	struct flow_head *head = tp->root;
401 	struct flow_filter *f;
402 	struct nlattr *opt = tca[TCA_OPTIONS];
403 	struct nlattr *tb[TCA_FLOW_MAX + 1];
404 	struct tcf_exts e;
405 	struct tcf_ematch_tree t;
406 	unsigned int nkeys = 0;
407 	unsigned int perturb_period = 0;
408 	u32 baseclass = 0;
409 	u32 keymask = 0;
410 	u32 mode;
411 	int err;
412 
413 	if (opt == NULL)
414 		return -EINVAL;
415 
416 	err = nla_parse_nested(tb, TCA_FLOW_MAX, opt, flow_policy);
417 	if (err < 0)
418 		return err;
419 
420 	if (tb[TCA_FLOW_BASECLASS]) {
421 		baseclass = nla_get_u32(tb[TCA_FLOW_BASECLASS]);
422 		if (TC_H_MIN(baseclass) == 0)
423 			return -EINVAL;
424 	}
425 
426 	if (tb[TCA_FLOW_KEYS]) {
427 		keymask = nla_get_u32(tb[TCA_FLOW_KEYS]);
428 
429 		nkeys = hweight32(keymask);
430 		if (nkeys == 0)
431 			return -EINVAL;
432 
433 		if (fls(keymask) - 1 > FLOW_KEY_MAX)
434 			return -EOPNOTSUPP;
435 	}
436 
437 	err = tcf_exts_validate(tp, tb, tca[TCA_RATE], &e, &flow_ext_map);
438 	if (err < 0)
439 		return err;
440 
441 	err = tcf_em_tree_validate(tp, tb[TCA_FLOW_EMATCHES], &t);
442 	if (err < 0)
443 		goto err1;
444 
445 	f = (struct flow_filter *)*arg;
446 	if (f != NULL) {
447 		err = -EINVAL;
448 		if (f->handle != handle && handle)
449 			goto err2;
450 
451 		mode = f->mode;
452 		if (tb[TCA_FLOW_MODE])
453 			mode = nla_get_u32(tb[TCA_FLOW_MODE]);
454 		if (mode != FLOW_MODE_HASH && nkeys > 1)
455 			goto err2;
456 
457 		if (mode == FLOW_MODE_HASH)
458 			perturb_period = f->perturb_period;
459 		if (tb[TCA_FLOW_PERTURB]) {
460 			if (mode != FLOW_MODE_HASH)
461 				goto err2;
462 			perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
463 		}
464 	} else {
465 		err = -EINVAL;
466 		if (!handle)
467 			goto err2;
468 		if (!tb[TCA_FLOW_KEYS])
469 			goto err2;
470 
471 		mode = FLOW_MODE_MAP;
472 		if (tb[TCA_FLOW_MODE])
473 			mode = nla_get_u32(tb[TCA_FLOW_MODE]);
474 		if (mode != FLOW_MODE_HASH && nkeys > 1)
475 			goto err2;
476 
477 		if (tb[TCA_FLOW_PERTURB]) {
478 			if (mode != FLOW_MODE_HASH)
479 				goto err2;
480 			perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
481 		}
482 
483 		if (TC_H_MAJ(baseclass) == 0)
484 			baseclass = TC_H_MAKE(tp->q->handle, baseclass);
485 		if (TC_H_MIN(baseclass) == 0)
486 			baseclass = TC_H_MAKE(baseclass, 1);
487 
488 		err = -ENOBUFS;
489 		f = kzalloc(sizeof(*f), GFP_KERNEL);
490 		if (f == NULL)
491 			goto err2;
492 
493 		f->handle = handle;
494 		f->mask	  = ~0U;
495 
496 		get_random_bytes(&f->hashrnd, 4);
497 		f->perturb_timer.function = flow_perturbation;
498 		f->perturb_timer.data = (unsigned long)f;
499 		init_timer_deferrable(&f->perturb_timer);
500 	}
501 
502 	tcf_exts_change(tp, &f->exts, &e);
503 	tcf_em_tree_change(tp, &f->ematches, &t);
504 
505 	tcf_tree_lock(tp);
506 
507 	if (tb[TCA_FLOW_KEYS]) {
508 		f->keymask = keymask;
509 		f->nkeys   = nkeys;
510 	}
511 
512 	f->mode = mode;
513 
514 	if (tb[TCA_FLOW_MASK])
515 		f->mask = nla_get_u32(tb[TCA_FLOW_MASK]);
516 	if (tb[TCA_FLOW_XOR])
517 		f->xor = nla_get_u32(tb[TCA_FLOW_XOR]);
518 	if (tb[TCA_FLOW_RSHIFT])
519 		f->rshift = nla_get_u32(tb[TCA_FLOW_RSHIFT]);
520 	if (tb[TCA_FLOW_ADDEND])
521 		f->addend = nla_get_u32(tb[TCA_FLOW_ADDEND]);
522 
523 	if (tb[TCA_FLOW_DIVISOR])
524 		f->divisor = nla_get_u32(tb[TCA_FLOW_DIVISOR]);
525 	if (baseclass)
526 		f->baseclass = baseclass;
527 
528 	f->perturb_period = perturb_period;
529 	del_timer(&f->perturb_timer);
530 	if (perturb_period)
531 		mod_timer(&f->perturb_timer, jiffies + perturb_period);
532 
533 	if (*arg == 0)
534 		list_add_tail(&f->list, &head->filters);
535 
536 	tcf_tree_unlock(tp);
537 
538 	*arg = (unsigned long)f;
539 	return 0;
540 
541 err2:
542 	tcf_em_tree_destroy(tp, &t);
543 err1:
544 	tcf_exts_destroy(tp, &e);
545 	return err;
546 }
547 
548 static void flow_destroy_filter(struct tcf_proto *tp, struct flow_filter *f)
549 {
550 	del_timer_sync(&f->perturb_timer);
551 	tcf_exts_destroy(tp, &f->exts);
552 	tcf_em_tree_destroy(tp, &f->ematches);
553 	kfree(f);
554 }
555 
556 static int flow_delete(struct tcf_proto *tp, unsigned long arg)
557 {
558 	struct flow_filter *f = (struct flow_filter *)arg;
559 
560 	tcf_tree_lock(tp);
561 	list_del(&f->list);
562 	tcf_tree_unlock(tp);
563 	flow_destroy_filter(tp, f);
564 	return 0;
565 }
566 
567 static int flow_init(struct tcf_proto *tp)
568 {
569 	struct flow_head *head;
570 
571 	head = kzalloc(sizeof(*head), GFP_KERNEL);
572 	if (head == NULL)
573 		return -ENOBUFS;
574 	INIT_LIST_HEAD(&head->filters);
575 	tp->root = head;
576 	return 0;
577 }
578 
579 static void flow_destroy(struct tcf_proto *tp)
580 {
581 	struct flow_head *head = tp->root;
582 	struct flow_filter *f, *next;
583 
584 	list_for_each_entry_safe(f, next, &head->filters, list) {
585 		list_del(&f->list);
586 		flow_destroy_filter(tp, f);
587 	}
588 	kfree(head);
589 }
590 
591 static unsigned long flow_get(struct tcf_proto *tp, u32 handle)
592 {
593 	struct flow_head *head = 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 void flow_put(struct tcf_proto *tp, unsigned long f)
603 {
604 	return;
605 }
606 
607 static int flow_dump(struct tcf_proto *tp, unsigned long fh,
608 		     struct sk_buff *skb, struct tcmsg *t)
609 {
610 	struct flow_filter *f = (struct flow_filter *)fh;
611 	struct nlattr *nest;
612 
613 	if (f == NULL)
614 		return skb->len;
615 
616 	t->tcm_handle = f->handle;
617 
618 	nest = nla_nest_start(skb, TCA_OPTIONS);
619 	if (nest == NULL)
620 		goto nla_put_failure;
621 
622 	NLA_PUT_U32(skb, TCA_FLOW_KEYS, f->keymask);
623 	NLA_PUT_U32(skb, TCA_FLOW_MODE, f->mode);
624 
625 	if (f->mask != ~0 || f->xor != 0) {
626 		NLA_PUT_U32(skb, TCA_FLOW_MASK, f->mask);
627 		NLA_PUT_U32(skb, TCA_FLOW_XOR, f->xor);
628 	}
629 	if (f->rshift)
630 		NLA_PUT_U32(skb, TCA_FLOW_RSHIFT, f->rshift);
631 	if (f->addend)
632 		NLA_PUT_U32(skb, TCA_FLOW_ADDEND, f->addend);
633 
634 	if (f->divisor)
635 		NLA_PUT_U32(skb, TCA_FLOW_DIVISOR, f->divisor);
636 	if (f->baseclass)
637 		NLA_PUT_U32(skb, TCA_FLOW_BASECLASS, f->baseclass);
638 
639 	if (f->perturb_period)
640 		NLA_PUT_U32(skb, TCA_FLOW_PERTURB, f->perturb_period / HZ);
641 
642 	if (tcf_exts_dump(skb, &f->exts, &flow_ext_map) < 0)
643 		goto nla_put_failure;
644 #ifdef CONFIG_NET_EMATCH
645 	if (f->ematches.hdr.nmatches &&
646 	    tcf_em_tree_dump(skb, &f->ematches, TCA_FLOW_EMATCHES) < 0)
647 		goto nla_put_failure;
648 #endif
649 	nla_nest_end(skb, nest);
650 
651 	if (tcf_exts_dump_stats(skb, &f->exts, &flow_ext_map) < 0)
652 		goto nla_put_failure;
653 
654 	return skb->len;
655 
656 nla_put_failure:
657 	nlmsg_trim(skb, nest);
658 	return -1;
659 }
660 
661 static void flow_walk(struct tcf_proto *tp, struct tcf_walker *arg)
662 {
663 	struct flow_head *head = tp->root;
664 	struct flow_filter *f;
665 
666 	list_for_each_entry(f, &head->filters, list) {
667 		if (arg->count < arg->skip)
668 			goto skip;
669 		if (arg->fn(tp, (unsigned long)f, arg) < 0) {
670 			arg->stop = 1;
671 			break;
672 		}
673 skip:
674 		arg->count++;
675 	}
676 }
677 
678 static struct tcf_proto_ops cls_flow_ops __read_mostly = {
679 	.kind		= "flow",
680 	.classify	= flow_classify,
681 	.init		= flow_init,
682 	.destroy	= flow_destroy,
683 	.change		= flow_change,
684 	.delete		= flow_delete,
685 	.get		= flow_get,
686 	.put		= flow_put,
687 	.dump		= flow_dump,
688 	.walk		= flow_walk,
689 	.owner		= THIS_MODULE,
690 };
691 
692 static int __init cls_flow_init(void)
693 {
694 	return register_tcf_proto_ops(&cls_flow_ops);
695 }
696 
697 static void __exit cls_flow_exit(void)
698 {
699 	unregister_tcf_proto_ops(&cls_flow_ops);
700 }
701 
702 module_init(cls_flow_init);
703 module_exit(cls_flow_exit);
704 
705 MODULE_LICENSE("GPL");
706 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
707 MODULE_DESCRIPTION("TC flow classifier");
708