xref: /linux/include/net/pkt_cls.h (revision d257f9bf06129613de539ea71ecea60848b662cd)
1 #ifndef __NET_PKT_CLS_H
2 #define __NET_PKT_CLS_H
3 
4 #include <linux/pkt_cls.h>
5 #include <net/sch_generic.h>
6 #include <net/act_api.h>
7 
8 /* Basic packet classifier frontend definitions. */
9 
10 struct tcf_walker {
11 	int	stop;
12 	int	skip;
13 	int	count;
14 	int	(*fn)(struct tcf_proto *, unsigned long node, struct tcf_walker *);
15 };
16 
17 int register_tcf_proto_ops(struct tcf_proto_ops *ops);
18 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops);
19 
20 #ifdef CONFIG_NET_CLS
21 struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
22 				bool create);
23 void tcf_chain_put(struct tcf_chain *chain);
24 int tcf_block_get(struct tcf_block **p_block,
25 		  struct tcf_proto __rcu **p_filter_chain);
26 void tcf_block_put(struct tcf_block *block);
27 int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
28 		 struct tcf_result *res, bool compat_mode);
29 
30 #else
31 static inline
32 int tcf_block_get(struct tcf_block **p_block,
33 		  struct tcf_proto __rcu **p_filter_chain)
34 {
35 	return 0;
36 }
37 
38 static inline void tcf_block_put(struct tcf_block *block)
39 {
40 }
41 
42 static inline int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
43 			       struct tcf_result *res, bool compat_mode)
44 {
45 	return TC_ACT_UNSPEC;
46 }
47 #endif
48 
49 static inline unsigned long
50 __cls_set_class(unsigned long *clp, unsigned long cl)
51 {
52 	return xchg(clp, cl);
53 }
54 
55 static inline unsigned long
56 cls_set_class(struct tcf_proto *tp, unsigned long *clp,
57 	unsigned long cl)
58 {
59 	unsigned long old_cl;
60 
61 	tcf_tree_lock(tp);
62 	old_cl = __cls_set_class(clp, cl);
63 	tcf_tree_unlock(tp);
64 
65 	return old_cl;
66 }
67 
68 static inline void
69 tcf_bind_filter(struct tcf_proto *tp, struct tcf_result *r, unsigned long base)
70 {
71 	unsigned long cl;
72 
73 	cl = tp->q->ops->cl_ops->bind_tcf(tp->q, base, r->classid);
74 	cl = cls_set_class(tp, &r->class, cl);
75 	if (cl)
76 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
77 }
78 
79 static inline void
80 tcf_unbind_filter(struct tcf_proto *tp, struct tcf_result *r)
81 {
82 	unsigned long cl;
83 
84 	if ((cl = __cls_set_class(&r->class, 0)) != 0)
85 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
86 }
87 
88 struct tcf_exts {
89 #ifdef CONFIG_NET_CLS_ACT
90 	__u32	type; /* for backward compat(TCA_OLD_COMPAT) */
91 	int nr_actions;
92 	struct tc_action **actions;
93 #endif
94 	/* Map to export classifier specific extension TLV types to the
95 	 * generic extensions API. Unsupported extensions must be set to 0.
96 	 */
97 	int action;
98 	int police;
99 };
100 
101 static inline int tcf_exts_init(struct tcf_exts *exts, int action, int police)
102 {
103 #ifdef CONFIG_NET_CLS_ACT
104 	exts->type = 0;
105 	exts->nr_actions = 0;
106 	exts->actions = kcalloc(TCA_ACT_MAX_PRIO, sizeof(struct tc_action *),
107 				GFP_KERNEL);
108 	if (!exts->actions)
109 		return -ENOMEM;
110 #endif
111 	exts->action = action;
112 	exts->police = police;
113 	return 0;
114 }
115 
116 /**
117  * tcf_exts_is_predicative - check if a predicative extension is present
118  * @exts: tc filter extensions handle
119  *
120  * Returns 1 if a predicative extension is present, i.e. an extension which
121  * might cause further actions and thus overrule the regular tcf_result.
122  */
123 static inline int
124 tcf_exts_is_predicative(struct tcf_exts *exts)
125 {
126 #ifdef CONFIG_NET_CLS_ACT
127 	return exts->nr_actions;
128 #else
129 	return 0;
130 #endif
131 }
132 
133 /**
134  * tcf_exts_is_available - check if at least one extension is present
135  * @exts: tc filter extensions handle
136  *
137  * Returns 1 if at least one extension is present.
138  */
139 static inline int
140 tcf_exts_is_available(struct tcf_exts *exts)
141 {
142 	/* All non-predicative extensions must be added here. */
143 	return tcf_exts_is_predicative(exts);
144 }
145 
146 static inline void tcf_exts_to_list(const struct tcf_exts *exts,
147 				    struct list_head *actions)
148 {
149 #ifdef CONFIG_NET_CLS_ACT
150 	int i;
151 
152 	for (i = 0; i < exts->nr_actions; i++) {
153 		struct tc_action *a = exts->actions[i];
154 
155 		list_add_tail(&a->list, actions);
156 	}
157 #endif
158 }
159 
160 static inline void
161 tcf_exts_stats_update(const struct tcf_exts *exts,
162 		      u64 bytes, u64 packets, u64 lastuse)
163 {
164 #ifdef CONFIG_NET_CLS_ACT
165 	int i;
166 
167 	preempt_disable();
168 
169 	for (i = 0; i < exts->nr_actions; i++) {
170 		struct tc_action *a = exts->actions[i];
171 
172 		tcf_action_stats_update(a, bytes, packets, lastuse);
173 	}
174 
175 	preempt_enable();
176 #endif
177 }
178 
179 /**
180  * tcf_exts_exec - execute tc filter extensions
181  * @skb: socket buffer
182  * @exts: tc filter extensions handle
183  * @res: desired result
184  *
185  * Executes all configured extensions. Returns 0 on a normal execution,
186  * a negative number if the filter must be considered unmatched or
187  * a positive action code (TC_ACT_*) which must be returned to the
188  * underlying layer.
189  */
190 static inline int
191 tcf_exts_exec(struct sk_buff *skb, struct tcf_exts *exts,
192 	       struct tcf_result *res)
193 {
194 #ifdef CONFIG_NET_CLS_ACT
195 	if (exts->nr_actions)
196 		return tcf_action_exec(skb, exts->actions, exts->nr_actions,
197 				       res);
198 #endif
199 	return 0;
200 }
201 
202 #ifdef CONFIG_NET_CLS_ACT
203 
204 #define tc_no_actions(_exts)  ((_exts)->nr_actions == 0)
205 #define tc_single_action(_exts) ((_exts)->nr_actions == 1)
206 
207 #else /* CONFIG_NET_CLS_ACT */
208 
209 #define tc_no_actions(_exts) true
210 #define tc_single_action(_exts) false
211 
212 #endif /* CONFIG_NET_CLS_ACT */
213 
214 int tcf_exts_validate(struct net *net, struct tcf_proto *tp,
215 		      struct nlattr **tb, struct nlattr *rate_tlv,
216 		      struct tcf_exts *exts, bool ovr);
217 void tcf_exts_destroy(struct tcf_exts *exts);
218 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
219 		     struct tcf_exts *src);
220 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts);
221 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts);
222 int tcf_exts_get_dev(struct net_device *dev, struct tcf_exts *exts,
223 		     struct net_device **hw_dev);
224 
225 /**
226  * struct tcf_pkt_info - packet information
227  */
228 struct tcf_pkt_info {
229 	unsigned char *		ptr;
230 	int			nexthdr;
231 };
232 
233 #ifdef CONFIG_NET_EMATCH
234 
235 struct tcf_ematch_ops;
236 
237 /**
238  * struct tcf_ematch - extended match (ematch)
239  *
240  * @matchid: identifier to allow userspace to reidentify a match
241  * @flags: flags specifying attributes and the relation to other matches
242  * @ops: the operations lookup table of the corresponding ematch module
243  * @datalen: length of the ematch specific configuration data
244  * @data: ematch specific data
245  */
246 struct tcf_ematch {
247 	struct tcf_ematch_ops * ops;
248 	unsigned long		data;
249 	unsigned int		datalen;
250 	u16			matchid;
251 	u16			flags;
252 	struct net		*net;
253 };
254 
255 static inline int tcf_em_is_container(struct tcf_ematch *em)
256 {
257 	return !em->ops;
258 }
259 
260 static inline int tcf_em_is_simple(struct tcf_ematch *em)
261 {
262 	return em->flags & TCF_EM_SIMPLE;
263 }
264 
265 static inline int tcf_em_is_inverted(struct tcf_ematch *em)
266 {
267 	return em->flags & TCF_EM_INVERT;
268 }
269 
270 static inline int tcf_em_last_match(struct tcf_ematch *em)
271 {
272 	return (em->flags & TCF_EM_REL_MASK) == TCF_EM_REL_END;
273 }
274 
275 static inline int tcf_em_early_end(struct tcf_ematch *em, int result)
276 {
277 	if (tcf_em_last_match(em))
278 		return 1;
279 
280 	if (result == 0 && em->flags & TCF_EM_REL_AND)
281 		return 1;
282 
283 	if (result != 0 && em->flags & TCF_EM_REL_OR)
284 		return 1;
285 
286 	return 0;
287 }
288 
289 /**
290  * struct tcf_ematch_tree - ematch tree handle
291  *
292  * @hdr: ematch tree header supplied by userspace
293  * @matches: array of ematches
294  */
295 struct tcf_ematch_tree {
296 	struct tcf_ematch_tree_hdr hdr;
297 	struct tcf_ematch *	matches;
298 
299 };
300 
301 /**
302  * struct tcf_ematch_ops - ematch module operations
303  *
304  * @kind: identifier (kind) of this ematch module
305  * @datalen: length of expected configuration data (optional)
306  * @change: called during validation (optional)
307  * @match: called during ematch tree evaluation, must return 1/0
308  * @destroy: called during destroyage (optional)
309  * @dump: called during dumping process (optional)
310  * @owner: owner, must be set to THIS_MODULE
311  * @link: link to previous/next ematch module (internal use)
312  */
313 struct tcf_ematch_ops {
314 	int			kind;
315 	int			datalen;
316 	int			(*change)(struct net *net, void *,
317 					  int, struct tcf_ematch *);
318 	int			(*match)(struct sk_buff *, struct tcf_ematch *,
319 					 struct tcf_pkt_info *);
320 	void			(*destroy)(struct tcf_ematch *);
321 	int			(*dump)(struct sk_buff *, struct tcf_ematch *);
322 	struct module		*owner;
323 	struct list_head	link;
324 };
325 
326 int tcf_em_register(struct tcf_ematch_ops *);
327 void tcf_em_unregister(struct tcf_ematch_ops *);
328 int tcf_em_tree_validate(struct tcf_proto *, struct nlattr *,
329 			 struct tcf_ematch_tree *);
330 void tcf_em_tree_destroy(struct tcf_ematch_tree *);
331 int tcf_em_tree_dump(struct sk_buff *, struct tcf_ematch_tree *, int);
332 int __tcf_em_tree_match(struct sk_buff *, struct tcf_ematch_tree *,
333 			struct tcf_pkt_info *);
334 
335 /**
336  * tcf_em_tree_change - replace ematch tree of a running classifier
337  *
338  * @tp: classifier kind handle
339  * @dst: destination ematch tree variable
340  * @src: source ematch tree (temporary tree from tcf_em_tree_validate)
341  *
342  * This functions replaces the ematch tree in @dst with the ematch
343  * tree in @src. The classifier in charge of the ematch tree may be
344  * running.
345  */
346 static inline void tcf_em_tree_change(struct tcf_proto *tp,
347 				      struct tcf_ematch_tree *dst,
348 				      struct tcf_ematch_tree *src)
349 {
350 	tcf_tree_lock(tp);
351 	memcpy(dst, src, sizeof(*dst));
352 	tcf_tree_unlock(tp);
353 }
354 
355 /**
356  * tcf_em_tree_match - evaulate an ematch tree
357  *
358  * @skb: socket buffer of the packet in question
359  * @tree: ematch tree to be used for evaluation
360  * @info: packet information examined by classifier
361  *
362  * This function matches @skb against the ematch tree in @tree by going
363  * through all ematches respecting their logic relations returning
364  * as soon as the result is obvious.
365  *
366  * Returns 1 if the ematch tree as-one matches, no ematches are configured
367  * or ematch is not enabled in the kernel, otherwise 0 is returned.
368  */
369 static inline int tcf_em_tree_match(struct sk_buff *skb,
370 				    struct tcf_ematch_tree *tree,
371 				    struct tcf_pkt_info *info)
372 {
373 	if (tree->hdr.nmatches)
374 		return __tcf_em_tree_match(skb, tree, info);
375 	else
376 		return 1;
377 }
378 
379 #define MODULE_ALIAS_TCF_EMATCH(kind)	MODULE_ALIAS("ematch-kind-" __stringify(kind))
380 
381 #else /* CONFIG_NET_EMATCH */
382 
383 struct tcf_ematch_tree {
384 };
385 
386 #define tcf_em_tree_validate(tp, tb, t) ((void)(t), 0)
387 #define tcf_em_tree_destroy(t) do { (void)(t); } while(0)
388 #define tcf_em_tree_dump(skb, t, tlv) (0)
389 #define tcf_em_tree_change(tp, dst, src) do { } while(0)
390 #define tcf_em_tree_match(skb, t, info) ((void)(info), 1)
391 
392 #endif /* CONFIG_NET_EMATCH */
393 
394 static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
395 {
396 	switch (layer) {
397 		case TCF_LAYER_LINK:
398 			return skb->data;
399 		case TCF_LAYER_NETWORK:
400 			return skb_network_header(skb);
401 		case TCF_LAYER_TRANSPORT:
402 			return skb_transport_header(skb);
403 	}
404 
405 	return NULL;
406 }
407 
408 static inline int tcf_valid_offset(const struct sk_buff *skb,
409 				   const unsigned char *ptr, const int len)
410 {
411 	return likely((ptr + len) <= skb_tail_pointer(skb) &&
412 		      ptr >= skb->head &&
413 		      (ptr <= (ptr + len)));
414 }
415 
416 #ifdef CONFIG_NET_CLS_IND
417 #include <net/net_namespace.h>
418 
419 static inline int
420 tcf_change_indev(struct net *net, struct nlattr *indev_tlv)
421 {
422 	char indev[IFNAMSIZ];
423 	struct net_device *dev;
424 
425 	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ)
426 		return -EINVAL;
427 	dev = __dev_get_by_name(net, indev);
428 	if (!dev)
429 		return -ENODEV;
430 	return dev->ifindex;
431 }
432 
433 static inline bool
434 tcf_match_indev(struct sk_buff *skb, int ifindex)
435 {
436 	if (!ifindex)
437 		return true;
438 	if  (!skb->skb_iif)
439 		return false;
440 	return ifindex == skb->skb_iif;
441 }
442 #endif /* CONFIG_NET_CLS_IND */
443 
444 struct tc_cls_u32_knode {
445 	struct tcf_exts *exts;
446 	struct tc_u32_sel *sel;
447 	u32 handle;
448 	u32 val;
449 	u32 mask;
450 	u32 link_handle;
451 	u8 fshift;
452 };
453 
454 struct tc_cls_u32_hnode {
455 	u32 handle;
456 	u32 prio;
457 	unsigned int divisor;
458 };
459 
460 enum tc_clsu32_command {
461 	TC_CLSU32_NEW_KNODE,
462 	TC_CLSU32_REPLACE_KNODE,
463 	TC_CLSU32_DELETE_KNODE,
464 	TC_CLSU32_NEW_HNODE,
465 	TC_CLSU32_REPLACE_HNODE,
466 	TC_CLSU32_DELETE_HNODE,
467 };
468 
469 struct tc_cls_u32_offload {
470 	/* knode values */
471 	enum tc_clsu32_command command;
472 	union {
473 		struct tc_cls_u32_knode knode;
474 		struct tc_cls_u32_hnode hnode;
475 	};
476 };
477 
478 static inline bool tc_can_offload(const struct net_device *dev,
479 				  const struct tcf_proto *tp)
480 {
481 	const struct Qdisc *sch = tp->q;
482 	const struct Qdisc_class_ops *cops = sch->ops->cl_ops;
483 
484 	if (!(dev->features & NETIF_F_HW_TC))
485 		return false;
486 	if (!dev->netdev_ops->ndo_setup_tc)
487 		return false;
488 	if (cops && cops->tcf_cl_offload)
489 		return cops->tcf_cl_offload(tp->classid);
490 
491 	return true;
492 }
493 
494 static inline bool tc_skip_hw(u32 flags)
495 {
496 	return (flags & TCA_CLS_FLAGS_SKIP_HW) ? true : false;
497 }
498 
499 static inline bool tc_should_offload(const struct net_device *dev,
500 				     const struct tcf_proto *tp, u32 flags)
501 {
502 	if (tc_skip_hw(flags))
503 		return false;
504 	return tc_can_offload(dev, tp);
505 }
506 
507 static inline bool tc_skip_sw(u32 flags)
508 {
509 	return (flags & TCA_CLS_FLAGS_SKIP_SW) ? true : false;
510 }
511 
512 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
513 static inline bool tc_flags_valid(u32 flags)
514 {
515 	if (flags & ~(TCA_CLS_FLAGS_SKIP_HW | TCA_CLS_FLAGS_SKIP_SW))
516 		return false;
517 
518 	if (!(flags ^ (TCA_CLS_FLAGS_SKIP_HW | TCA_CLS_FLAGS_SKIP_SW)))
519 		return false;
520 
521 	return true;
522 }
523 
524 static inline bool tc_in_hw(u32 flags)
525 {
526 	return (flags & TCA_CLS_FLAGS_IN_HW) ? true : false;
527 }
528 
529 enum tc_fl_command {
530 	TC_CLSFLOWER_REPLACE,
531 	TC_CLSFLOWER_DESTROY,
532 	TC_CLSFLOWER_STATS,
533 };
534 
535 struct tc_cls_flower_offload {
536 	enum tc_fl_command command;
537 	u32 prio;
538 	unsigned long cookie;
539 	struct flow_dissector *dissector;
540 	struct fl_flow_key *mask;
541 	struct fl_flow_key *key;
542 	struct tcf_exts *exts;
543 };
544 
545 enum tc_matchall_command {
546 	TC_CLSMATCHALL_REPLACE,
547 	TC_CLSMATCHALL_DESTROY,
548 };
549 
550 struct tc_cls_matchall_offload {
551 	enum tc_matchall_command command;
552 	struct tcf_exts *exts;
553 	unsigned long cookie;
554 };
555 
556 enum tc_clsbpf_command {
557 	TC_CLSBPF_ADD,
558 	TC_CLSBPF_REPLACE,
559 	TC_CLSBPF_DESTROY,
560 	TC_CLSBPF_STATS,
561 };
562 
563 struct tc_cls_bpf_offload {
564 	enum tc_clsbpf_command command;
565 	struct tcf_exts *exts;
566 	struct bpf_prog *prog;
567 	const char *name;
568 	bool exts_integrated;
569 	u32 gen_flags;
570 };
571 
572 
573 /* This structure holds cookie structure that is passed from user
574  * to the kernel for actions and classifiers
575  */
576 struct tc_cookie {
577 	u8  *data;
578 	u32 len;
579 };
580 #endif
581