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v4.6
 
  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
 36struct flow_head {
 37	struct list_head	filters;
 38	struct rcu_head		rcu;
 39};
 40
 41struct 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
 63static 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
 70static 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
 80static 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
 90static u32 flow_get_proto(const struct sk_buff *skb, const struct flow_keys *flow)
 
 91{
 92	return flow->basic.ip_proto;
 93}
 94
 95static 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
103static 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
111static u32 flow_get_iif(const struct sk_buff *skb)
112{
113	return skb->skb_iif;
114}
115
116static u32 flow_get_priority(const struct sk_buff *skb)
117{
118	return skb->priority;
119}
120
121static u32 flow_get_mark(const struct sk_buff *skb)
122{
123	return skb->mark;
124}
125
126static 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
152static 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	}
160fallback:
161	return flow_get_src(skb, flow);
162}
163
164static 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	}
172fallback:
173	return flow_get_dst(skb, flow);
174}
175
176static 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));
179fallback:
180	return flow_get_proto_src(skb, flow);
181}
182
183static 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));
186fallback:
187	return flow_get_proto_dst(skb, flow);
188}
189
190static 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
199static 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
211static 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
223static 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
232static u32 flow_get_rxhash(struct sk_buff *skb)
233{
234	return skb_get_hash(skb);
235}
236
237static 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
292static 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
341static 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
350static 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
365static 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
 
 
 
 
 
 
 
 
 
 
375static 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
545err2:
546	tcf_em_tree_destroy(&t);
547	kfree(fnew);
548err1:
549	tcf_exts_destroy(&e);
550	return err;
551}
552
553static 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
562static 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
574static 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
591static 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
602static 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
658nla_put_failure:
659	nla_nest_cancel(skb, nest);
660	return -1;
661}
662
663static 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		}
675skip:
676		arg->count++;
677	}
678}
679
680static 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
693static int __init cls_flow_init(void)
694{
695	return register_tcf_proto_ops(&cls_flow_ops);
696}
697
698static void __exit cls_flow_exit(void)
699{
700	unregister_tcf_proto_ops(&cls_flow_ops);
701}
702
703module_init(cls_flow_init);
704module_exit(cls_flow_exit);
705
706MODULE_LICENSE("GPL");
707MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
708MODULE_DESCRIPTION("TC flow classifier");
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * net/sched/cls_flow.c		Generic flow classifier
  4 *
  5 * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net>
 
 
 
 
 
  6 */
  7
  8#include <linux/kernel.h>
  9#include <linux/init.h>
 10#include <linux/list.h>
 11#include <linux/jhash.h>
 12#include <linux/random.h>
 13#include <linux/pkt_cls.h>
 14#include <linux/skbuff.h>
 15#include <linux/in.h>
 16#include <linux/ip.h>
 17#include <linux/ipv6.h>
 18#include <linux/if_vlan.h>
 19#include <linux/slab.h>
 20#include <linux/module.h>
 21#include <net/inet_sock.h>
 22
 23#include <net/pkt_cls.h>
 24#include <net/ip.h>
 25#include <net/route.h>
 26#include <net/flow_dissector.h>
 27#include <net/tc_wrapper.h>
 28
 29#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 30#include <net/netfilter/nf_conntrack.h>
 31#endif
 32
 33struct flow_head {
 34	struct list_head	filters;
 35	struct rcu_head		rcu;
 36};
 37
 38struct flow_filter {
 39	struct list_head	list;
 40	struct tcf_exts		exts;
 41	struct tcf_ematch_tree	ematches;
 42	struct tcf_proto	*tp;
 43	struct timer_list	perturb_timer;
 44	u32			perturb_period;
 45	u32			handle;
 46
 47	u32			nkeys;
 48	u32			keymask;
 49	u32			mode;
 50	u32			mask;
 51	u32			xor;
 52	u32			rshift;
 53	u32			addend;
 54	u32			divisor;
 55	u32			baseclass;
 56	u32			hashrnd;
 57	struct rcu_work		rwork;
 58};
 59
 60static 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
 67static u32 flow_get_src(const struct sk_buff *skb, const struct flow_keys *flow)
 68{
 69	__be32 src = flow_get_u32_src(flow);
 70
 71	if (src)
 72		return ntohl(src);
 73
 74	return addr_fold(skb->sk);
 75}
 76
 77static u32 flow_get_dst(const struct sk_buff *skb, const struct flow_keys *flow)
 78{
 79	__be32 dst = flow_get_u32_dst(flow);
 80
 81	if (dst)
 82		return ntohl(dst);
 83
 84	return addr_fold(skb_dst(skb)) ^ (__force u16)skb_protocol(skb, true);
 85}
 86
 87static u32 flow_get_proto(const struct sk_buff *skb,
 88			  const struct flow_keys *flow)
 89{
 90	return flow->basic.ip_proto;
 91}
 92
 93static u32 flow_get_proto_src(const struct sk_buff *skb,
 94			      const struct flow_keys *flow)
 95{
 96	if (flow->ports.ports)
 97		return ntohs(flow->ports.src);
 98
 99	return addr_fold(skb->sk);
100}
101
102static u32 flow_get_proto_dst(const struct sk_buff *skb,
103			      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)skb_protocol(skb, true);
109}
110
111static u32 flow_get_iif(const struct sk_buff *skb)
112{
113	return skb->skb_iif;
114}
115
116static u32 flow_get_priority(const struct sk_buff *skb)
117{
118	return skb->priority;
119}
120
121static u32 flow_get_mark(const struct sk_buff *skb)
122{
123	return skb->mark;
124}
125
126static u32 flow_get_nfct(const struct sk_buff *skb)
127{
128#if IS_ENABLED(CONFIG_NF_CONNTRACK)
129	return addr_fold(skb_nfct(skb));
130#else
131	return 0;
132#endif
133}
134
135#if IS_ENABLED(CONFIG_NF_CONNTRACK)
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
152static u32 flow_get_nfct_src(const struct sk_buff *skb,
153			     const struct flow_keys *flow)
154{
155	switch (skb_protocol(skb, true)) {
156	case htons(ETH_P_IP):
157		return ntohl(CTTUPLE(skb, src.u3.ip));
158	case htons(ETH_P_IPV6):
159		return ntohl(CTTUPLE(skb, src.u3.ip6[3]));
160	}
161fallback:
162	return flow_get_src(skb, flow);
163}
164
165static u32 flow_get_nfct_dst(const struct sk_buff *skb,
166			     const struct flow_keys *flow)
167{
168	switch (skb_protocol(skb, true)) {
169	case htons(ETH_P_IP):
170		return ntohl(CTTUPLE(skb, dst.u3.ip));
171	case htons(ETH_P_IPV6):
172		return ntohl(CTTUPLE(skb, dst.u3.ip6[3]));
173	}
174fallback:
175	return flow_get_dst(skb, flow);
176}
177
178static u32 flow_get_nfct_proto_src(const struct sk_buff *skb,
179				   const struct flow_keys *flow)
180{
181	return ntohs(CTTUPLE(skb, src.u.all));
182fallback:
183	return flow_get_proto_src(skb, flow);
184}
185
186static u32 flow_get_nfct_proto_dst(const struct sk_buff *skb,
187				   const struct flow_keys *flow)
188{
189	return ntohs(CTTUPLE(skb, dst.u.all));
190fallback:
191	return flow_get_proto_dst(skb, flow);
192}
193
194static u32 flow_get_rtclassid(const struct sk_buff *skb)
195{
196#ifdef CONFIG_IP_ROUTE_CLASSID
197	if (skb_dst(skb))
198		return skb_dst(skb)->tclassid;
199#endif
200	return 0;
201}
202
203static u32 flow_get_skuid(const struct sk_buff *skb)
204{
205	struct sock *sk = skb_to_full_sk(skb);
206
207	if (sk && sk->sk_socket && sk->sk_socket->file) {
208		kuid_t skuid = sk->sk_socket->file->f_cred->fsuid;
209
210		return from_kuid(&init_user_ns, skuid);
211	}
212	return 0;
213}
214
215static u32 flow_get_skgid(const struct sk_buff *skb)
216{
217	struct sock *sk = skb_to_full_sk(skb);
218
219	if (sk && sk->sk_socket && sk->sk_socket->file) {
220		kgid_t skgid = sk->sk_socket->file->f_cred->fsgid;
221
222		return from_kgid(&init_user_ns, skgid);
223	}
224	return 0;
225}
226
227static u32 flow_get_vlan_tag(const struct sk_buff *skb)
228{
229	u16 tag;
230
231	if (vlan_get_tag(skb, &tag) < 0)
232		return 0;
233	return tag & VLAN_VID_MASK;
234}
235
236static u32 flow_get_rxhash(struct sk_buff *skb)
237{
238	return skb_get_hash(skb);
239}
240
241static u32 flow_key_get(struct sk_buff *skb, int key, struct flow_keys *flow)
242{
243	switch (key) {
244	case FLOW_KEY_SRC:
245		return flow_get_src(skb, flow);
246	case FLOW_KEY_DST:
247		return flow_get_dst(skb, flow);
248	case FLOW_KEY_PROTO:
249		return flow_get_proto(skb, flow);
250	case FLOW_KEY_PROTO_SRC:
251		return flow_get_proto_src(skb, flow);
252	case FLOW_KEY_PROTO_DST:
253		return flow_get_proto_dst(skb, flow);
254	case FLOW_KEY_IIF:
255		return flow_get_iif(skb);
256	case FLOW_KEY_PRIORITY:
257		return flow_get_priority(skb);
258	case FLOW_KEY_MARK:
259		return flow_get_mark(skb);
260	case FLOW_KEY_NFCT:
261		return flow_get_nfct(skb);
262	case FLOW_KEY_NFCT_SRC:
263		return flow_get_nfct_src(skb, flow);
264	case FLOW_KEY_NFCT_DST:
265		return flow_get_nfct_dst(skb, flow);
266	case FLOW_KEY_NFCT_PROTO_SRC:
267		return flow_get_nfct_proto_src(skb, flow);
268	case FLOW_KEY_NFCT_PROTO_DST:
269		return flow_get_nfct_proto_dst(skb, flow);
270	case FLOW_KEY_RTCLASSID:
271		return flow_get_rtclassid(skb);
272	case FLOW_KEY_SKUID:
273		return flow_get_skuid(skb);
274	case FLOW_KEY_SKGID:
275		return flow_get_skgid(skb);
276	case FLOW_KEY_VLAN_TAG:
277		return flow_get_vlan_tag(skb);
278	case FLOW_KEY_RXHASH:
279		return flow_get_rxhash(skb);
280	default:
281		WARN_ON(1);
282		return 0;
283	}
284}
285
286#define FLOW_KEYS_NEEDED ((1 << FLOW_KEY_SRC) | 		\
287			  (1 << FLOW_KEY_DST) |			\
288			  (1 << FLOW_KEY_PROTO) |		\
289			  (1 << FLOW_KEY_PROTO_SRC) |		\
290			  (1 << FLOW_KEY_PROTO_DST) | 		\
291			  (1 << FLOW_KEY_NFCT_SRC) |		\
292			  (1 << FLOW_KEY_NFCT_DST) |		\
293			  (1 << FLOW_KEY_NFCT_PROTO_SRC) |	\
294			  (1 << FLOW_KEY_NFCT_PROTO_DST))
295
296TC_INDIRECT_SCOPE int flow_classify(struct sk_buff *skb,
297				    const struct tcf_proto *tp,
298				    struct tcf_result *res)
299{
300	struct flow_head *head = rcu_dereference_bh(tp->root);
301	struct flow_filter *f;
302	u32 keymask;
303	u32 classid;
304	unsigned int n, key;
305	int r;
306
307	list_for_each_entry_rcu(f, &head->filters, list) {
308		u32 keys[FLOW_KEY_MAX + 1];
309		struct flow_keys flow_keys;
310
311		if (!tcf_em_tree_match(skb, &f->ematches, NULL))
312			continue;
313
314		keymask = f->keymask;
315		if (keymask & FLOW_KEYS_NEEDED)
316			skb_flow_dissect_flow_keys(skb, &flow_keys, 0);
317
318		for (n = 0; n < f->nkeys; n++) {
319			key = ffs(keymask) - 1;
320			keymask &= ~(1 << key);
321			keys[n] = flow_key_get(skb, key, &flow_keys);
322		}
323
324		if (f->mode == FLOW_MODE_HASH)
325			classid = jhash2(keys, f->nkeys, f->hashrnd);
326		else {
327			classid = keys[0];
328			classid = (classid & f->mask) ^ f->xor;
329			classid = (classid >> f->rshift) + f->addend;
330		}
331
332		if (f->divisor)
333			classid %= f->divisor;
334
335		res->class   = 0;
336		res->classid = TC_H_MAKE(f->baseclass, f->baseclass + classid);
337
338		r = tcf_exts_exec(skb, &f->exts, res);
339		if (r < 0)
340			continue;
341		return r;
342	}
343	return -1;
344}
345
346static void flow_perturbation(struct timer_list *t)
347{
348	struct flow_filter *f = from_timer(f, t, perturb_timer);
349
350	get_random_bytes(&f->hashrnd, 4);
351	if (f->perturb_period)
352		mod_timer(&f->perturb_timer, jiffies + f->perturb_period);
353}
354
355static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = {
356	[TCA_FLOW_KEYS]		= { .type = NLA_U32 },
357	[TCA_FLOW_MODE]		= { .type = NLA_U32 },
358	[TCA_FLOW_BASECLASS]	= { .type = NLA_U32 },
359	[TCA_FLOW_RSHIFT]	= NLA_POLICY_MAX(NLA_U32,
360						 31 /* BITS_PER_U32 - 1 */),
361	[TCA_FLOW_ADDEND]	= { .type = NLA_U32 },
362	[TCA_FLOW_MASK]		= { .type = NLA_U32 },
363	[TCA_FLOW_XOR]		= { .type = NLA_U32 },
364	[TCA_FLOW_DIVISOR]	= { .type = NLA_U32 },
365	[TCA_FLOW_ACT]		= { .type = NLA_NESTED },
366	[TCA_FLOW_POLICE]	= { .type = NLA_NESTED },
367	[TCA_FLOW_EMATCHES]	= { .type = NLA_NESTED },
368	[TCA_FLOW_PERTURB]	= { .type = NLA_U32 },
369};
370
371static void __flow_destroy_filter(struct flow_filter *f)
372{
373	timer_shutdown_sync(&f->perturb_timer);
 
 
374	tcf_exts_destroy(&f->exts);
375	tcf_em_tree_destroy(&f->ematches);
376	tcf_exts_put_net(&f->exts);
377	kfree(f);
378}
379
380static void flow_destroy_filter_work(struct work_struct *work)
381{
382	struct flow_filter *f = container_of(to_rcu_work(work),
383					     struct flow_filter,
384					     rwork);
385	rtnl_lock();
386	__flow_destroy_filter(f);
387	rtnl_unlock();
388}
389
390static int flow_change(struct net *net, struct sk_buff *in_skb,
391		       struct tcf_proto *tp, unsigned long base,
392		       u32 handle, struct nlattr **tca,
393		       void **arg, u32 flags,
394		       struct netlink_ext_ack *extack)
395{
396	struct flow_head *head = rtnl_dereference(tp->root);
397	struct flow_filter *fold, *fnew;
398	struct nlattr *opt = tca[TCA_OPTIONS];
399	struct nlattr *tb[TCA_FLOW_MAX + 1];
 
 
400	unsigned int nkeys = 0;
401	unsigned int perturb_period = 0;
402	u32 baseclass = 0;
403	u32 keymask = 0;
404	u32 mode;
405	int err;
406
407	if (opt == NULL)
408		return -EINVAL;
409
410	err = nla_parse_nested_deprecated(tb, TCA_FLOW_MAX, opt, flow_policy,
411					  NULL);
412	if (err < 0)
413		return err;
414
415	if (tb[TCA_FLOW_BASECLASS]) {
416		baseclass = nla_get_u32(tb[TCA_FLOW_BASECLASS]);
417		if (TC_H_MIN(baseclass) == 0)
418			return -EINVAL;
419	}
420
421	if (tb[TCA_FLOW_KEYS]) {
422		keymask = nla_get_u32(tb[TCA_FLOW_KEYS]);
423
424		nkeys = hweight32(keymask);
425		if (nkeys == 0)
426			return -EINVAL;
427
428		if (fls(keymask) - 1 > FLOW_KEY_MAX)
429			return -EOPNOTSUPP;
430
431		if ((keymask & (FLOW_KEY_SKUID|FLOW_KEY_SKGID)) &&
432		    sk_user_ns(NETLINK_CB(in_skb).sk) != &init_user_ns)
433			return -EOPNOTSUPP;
434	}
435
436	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
437	if (!fnew)
438		return -ENOBUFS;
 
439
440	err = tcf_em_tree_validate(tp, tb[TCA_FLOW_EMATCHES], &fnew->ematches);
441	if (err < 0)
442		goto err1;
443
444	err = tcf_exts_init(&fnew->exts, net, TCA_FLOW_ACT, TCA_FLOW_POLICE);
445	if (err < 0)
 
446		goto err2;
447
448	err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &fnew->exts, flags,
449				extack);
450	if (err < 0)
451		goto err2;
452
453	fold = *arg;
454	if (fold) {
455		err = -EINVAL;
456		if (fold->handle != handle && handle)
457			goto err2;
458
459		/* Copy fold into fnew */
460		fnew->tp = fold->tp;
461		fnew->handle = fold->handle;
462		fnew->nkeys = fold->nkeys;
463		fnew->keymask = fold->keymask;
464		fnew->mode = fold->mode;
465		fnew->mask = fold->mask;
466		fnew->xor = fold->xor;
467		fnew->rshift = fold->rshift;
468		fnew->addend = fold->addend;
469		fnew->divisor = fold->divisor;
470		fnew->baseclass = fold->baseclass;
471		fnew->hashrnd = fold->hashrnd;
472
473		mode = fold->mode;
474		if (tb[TCA_FLOW_MODE])
475			mode = nla_get_u32(tb[TCA_FLOW_MODE]);
476		if (mode != FLOW_MODE_HASH && nkeys > 1)
477			goto err2;
478
479		if (mode == FLOW_MODE_HASH)
480			perturb_period = fold->perturb_period;
481		if (tb[TCA_FLOW_PERTURB]) {
482			if (mode != FLOW_MODE_HASH)
483				goto err2;
484			perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
485		}
486	} else {
487		err = -EINVAL;
488		if (!handle)
489			goto err2;
490		if (!tb[TCA_FLOW_KEYS])
491			goto err2;
492
493		mode = FLOW_MODE_MAP;
494		if (tb[TCA_FLOW_MODE])
495			mode = nla_get_u32(tb[TCA_FLOW_MODE]);
496		if (mode != FLOW_MODE_HASH && nkeys > 1)
497			goto err2;
498
499		if (tb[TCA_FLOW_PERTURB]) {
500			if (mode != FLOW_MODE_HASH)
501				goto err2;
502			perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
503		}
504
505		if (TC_H_MAJ(baseclass) == 0) {
506			struct Qdisc *q = tcf_block_q(tp->chain->block);
507
508			baseclass = TC_H_MAKE(q->handle, baseclass);
509		}
510		if (TC_H_MIN(baseclass) == 0)
511			baseclass = TC_H_MAKE(baseclass, 1);
512
513		fnew->handle = handle;
514		fnew->mask  = ~0U;
515		fnew->tp = tp;
516		get_random_bytes(&fnew->hashrnd, 4);
517	}
518
519	timer_setup(&fnew->perturb_timer, flow_perturbation, TIMER_DEFERRABLE);
 
 
520
521	tcf_block_netif_keep_dst(tp->chain->block);
 
 
 
522
523	if (tb[TCA_FLOW_KEYS]) {
524		fnew->keymask = keymask;
525		fnew->nkeys   = nkeys;
526	}
527
528	fnew->mode = mode;
529
530	if (tb[TCA_FLOW_MASK])
531		fnew->mask = nla_get_u32(tb[TCA_FLOW_MASK]);
532	if (tb[TCA_FLOW_XOR])
533		fnew->xor = nla_get_u32(tb[TCA_FLOW_XOR]);
534	if (tb[TCA_FLOW_RSHIFT])
535		fnew->rshift = nla_get_u32(tb[TCA_FLOW_RSHIFT]);
536	if (tb[TCA_FLOW_ADDEND])
537		fnew->addend = nla_get_u32(tb[TCA_FLOW_ADDEND]);
538
539	if (tb[TCA_FLOW_DIVISOR])
540		fnew->divisor = nla_get_u32(tb[TCA_FLOW_DIVISOR]);
541	if (baseclass)
542		fnew->baseclass = baseclass;
543
544	fnew->perturb_period = perturb_period;
545	if (perturb_period)
546		mod_timer(&fnew->perturb_timer, jiffies + perturb_period);
547
548	if (!*arg)
549		list_add_tail_rcu(&fnew->list, &head->filters);
550	else
551		list_replace_rcu(&fold->list, &fnew->list);
552
553	*arg = fnew;
554
555	if (fold) {
556		tcf_exts_get_net(&fold->exts);
557		tcf_queue_work(&fold->rwork, flow_destroy_filter_work);
558	}
559	return 0;
560
561err2:
562	tcf_exts_destroy(&fnew->exts);
563	tcf_em_tree_destroy(&fnew->ematches);
564err1:
565	kfree(fnew);
566	return err;
567}
568
569static int flow_delete(struct tcf_proto *tp, void *arg, bool *last,
570		       bool rtnl_held, struct netlink_ext_ack *extack)
571{
572	struct flow_head *head = rtnl_dereference(tp->root);
573	struct flow_filter *f = arg;
574
575	list_del_rcu(&f->list);
576	tcf_exts_get_net(&f->exts);
577	tcf_queue_work(&f->rwork, flow_destroy_filter_work);
578	*last = list_empty(&head->filters);
579	return 0;
580}
581
582static int flow_init(struct tcf_proto *tp)
583{
584	struct flow_head *head;
585
586	head = kzalloc(sizeof(*head), GFP_KERNEL);
587	if (head == NULL)
588		return -ENOBUFS;
589	INIT_LIST_HEAD(&head->filters);
590	rcu_assign_pointer(tp->root, head);
591	return 0;
592}
593
594static void flow_destroy(struct tcf_proto *tp, bool rtnl_held,
595			 struct netlink_ext_ack *extack)
596{
597	struct flow_head *head = rtnl_dereference(tp->root);
598	struct flow_filter *f, *next;
599
 
 
 
600	list_for_each_entry_safe(f, next, &head->filters, list) {
601		list_del_rcu(&f->list);
602		if (tcf_exts_get_net(&f->exts))
603			tcf_queue_work(&f->rwork, flow_destroy_filter_work);
604		else
605			__flow_destroy_filter(f);
606	}
 
607	kfree_rcu(head, rcu);
 
608}
609
610static void *flow_get(struct tcf_proto *tp, u32 handle)
611{
612	struct flow_head *head = rtnl_dereference(tp->root);
613	struct flow_filter *f;
614
615	list_for_each_entry(f, &head->filters, list)
616		if (f->handle == handle)
617			return f;
618	return NULL;
619}
620
621static int flow_dump(struct net *net, struct tcf_proto *tp, void *fh,
622		     struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
623{
624	struct flow_filter *f = fh;
625	struct nlattr *nest;
626
627	if (f == NULL)
628		return skb->len;
629
630	t->tcm_handle = f->handle;
631
632	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
633	if (nest == NULL)
634		goto nla_put_failure;
635
636	if (nla_put_u32(skb, TCA_FLOW_KEYS, f->keymask) ||
637	    nla_put_u32(skb, TCA_FLOW_MODE, f->mode))
638		goto nla_put_failure;
639
640	if (f->mask != ~0 || f->xor != 0) {
641		if (nla_put_u32(skb, TCA_FLOW_MASK, f->mask) ||
642		    nla_put_u32(skb, TCA_FLOW_XOR, f->xor))
643			goto nla_put_failure;
644	}
645	if (f->rshift &&
646	    nla_put_u32(skb, TCA_FLOW_RSHIFT, f->rshift))
647		goto nla_put_failure;
648	if (f->addend &&
649	    nla_put_u32(skb, TCA_FLOW_ADDEND, f->addend))
650		goto nla_put_failure;
651
652	if (f->divisor &&
653	    nla_put_u32(skb, TCA_FLOW_DIVISOR, f->divisor))
654		goto nla_put_failure;
655	if (f->baseclass &&
656	    nla_put_u32(skb, TCA_FLOW_BASECLASS, f->baseclass))
657		goto nla_put_failure;
658
659	if (f->perturb_period &&
660	    nla_put_u32(skb, TCA_FLOW_PERTURB, f->perturb_period / HZ))
661		goto nla_put_failure;
662
663	if (tcf_exts_dump(skb, &f->exts) < 0)
664		goto nla_put_failure;
665#ifdef CONFIG_NET_EMATCH
666	if (f->ematches.hdr.nmatches &&
667	    tcf_em_tree_dump(skb, &f->ematches, TCA_FLOW_EMATCHES) < 0)
668		goto nla_put_failure;
669#endif
670	nla_nest_end(skb, nest);
671
672	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
673		goto nla_put_failure;
674
675	return skb->len;
676
677nla_put_failure:
678	nla_nest_cancel(skb, nest);
679	return -1;
680}
681
682static void flow_walk(struct tcf_proto *tp, struct tcf_walker *arg,
683		      bool rtnl_held)
684{
685	struct flow_head *head = rtnl_dereference(tp->root);
686	struct flow_filter *f;
687
688	list_for_each_entry(f, &head->filters, list) {
689		if (!tc_cls_stats_dump(tp, arg, f))
 
 
 
690			break;
 
 
 
691	}
692}
693
694static struct tcf_proto_ops cls_flow_ops __read_mostly = {
695	.kind		= "flow",
696	.classify	= flow_classify,
697	.init		= flow_init,
698	.destroy	= flow_destroy,
699	.change		= flow_change,
700	.delete		= flow_delete,
701	.get		= flow_get,
702	.dump		= flow_dump,
703	.walk		= flow_walk,
704	.owner		= THIS_MODULE,
705};
706MODULE_ALIAS_NET_CLS("flow");
707
708static int __init cls_flow_init(void)
709{
710	return register_tcf_proto_ops(&cls_flow_ops);
711}
712
713static void __exit cls_flow_exit(void)
714{
715	unregister_tcf_proto_ops(&cls_flow_ops);
716}
717
718module_init(cls_flow_init);
719module_exit(cls_flow_exit);
720
721MODULE_LICENSE("GPL");
722MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
723MODULE_DESCRIPTION("TC flow classifier");