xref: /linux/include/net/pkt_cls.h (revision bb9707077b4ee5f77bc9939b057ff8a0d410296f)
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 static inline unsigned long
21 __cls_set_class(unsigned long *clp, unsigned long cl)
22 {
23 	return xchg(clp, cl);
24 }
25 
26 static inline unsigned long
27 cls_set_class(struct tcf_proto *tp, unsigned long *clp,
28 	unsigned long cl)
29 {
30 	unsigned long old_cl;
31 
32 	tcf_tree_lock(tp);
33 	old_cl = __cls_set_class(clp, cl);
34 	tcf_tree_unlock(tp);
35 
36 	return old_cl;
37 }
38 
39 static inline void
40 tcf_bind_filter(struct tcf_proto *tp, struct tcf_result *r, unsigned long base)
41 {
42 	unsigned long cl;
43 
44 	cl = tp->q->ops->cl_ops->bind_tcf(tp->q, base, r->classid);
45 	cl = cls_set_class(tp, &r->class, cl);
46 	if (cl)
47 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
48 }
49 
50 static inline void
51 tcf_unbind_filter(struct tcf_proto *tp, struct tcf_result *r)
52 {
53 	unsigned long cl;
54 
55 	if ((cl = __cls_set_class(&r->class, 0)) != 0)
56 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
57 }
58 
59 struct tcf_exts {
60 #ifdef CONFIG_NET_CLS_ACT
61 	__u32	type; /* for backward compat(TCA_OLD_COMPAT) */
62 	struct list_head actions;
63 #endif
64 	/* Map to export classifier specific extension TLV types to the
65 	 * generic extensions API. Unsupported extensions must be set to 0.
66 	 */
67 	int action;
68 	int police;
69 };
70 
71 static inline void tcf_exts_init(struct tcf_exts *exts, int action, int police)
72 {
73 #ifdef CONFIG_NET_CLS_ACT
74 	exts->type = 0;
75 	INIT_LIST_HEAD(&exts->actions);
76 #endif
77 	exts->action = action;
78 	exts->police = police;
79 }
80 
81 /**
82  * tcf_exts_is_predicative - check if a predicative extension is present
83  * @exts: tc filter extensions handle
84  *
85  * Returns 1 if a predicative extension is present, i.e. an extension which
86  * might cause further actions and thus overrule the regular tcf_result.
87  */
88 static inline int
89 tcf_exts_is_predicative(struct tcf_exts *exts)
90 {
91 #ifdef CONFIG_NET_CLS_ACT
92 	return !list_empty(&exts->actions);
93 #else
94 	return 0;
95 #endif
96 }
97 
98 /**
99  * tcf_exts_is_available - check if at least one extension is present
100  * @exts: tc filter extensions handle
101  *
102  * Returns 1 if at least one extension is present.
103  */
104 static inline int
105 tcf_exts_is_available(struct tcf_exts *exts)
106 {
107 	/* All non-predicative extensions must be added here. */
108 	return tcf_exts_is_predicative(exts);
109 }
110 
111 /**
112  * tcf_exts_exec - execute tc filter extensions
113  * @skb: socket buffer
114  * @exts: tc filter extensions handle
115  * @res: desired result
116  *
117  * Executes all configured extensions. Returns 0 on a normal execution,
118  * a negative number if the filter must be considered unmatched or
119  * a positive action code (TC_ACT_*) which must be returned to the
120  * underlying layer.
121  */
122 static inline int
123 tcf_exts_exec(struct sk_buff *skb, struct tcf_exts *exts,
124 	       struct tcf_result *res)
125 {
126 #ifdef CONFIG_NET_CLS_ACT
127 	if (!list_empty(&exts->actions))
128 		return tcf_action_exec(skb, &exts->actions, res);
129 #endif
130 	return 0;
131 }
132 
133 int tcf_exts_validate(struct net *net, struct tcf_proto *tp,
134 		      struct nlattr **tb, struct nlattr *rate_tlv,
135 		      struct tcf_exts *exts, bool ovr);
136 void tcf_exts_destroy(struct tcf_exts *exts);
137 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
138 		     struct tcf_exts *src);
139 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts);
140 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts);
141 
142 /**
143  * struct tcf_pkt_info - packet information
144  */
145 struct tcf_pkt_info {
146 	unsigned char *		ptr;
147 	int			nexthdr;
148 };
149 
150 #ifdef CONFIG_NET_EMATCH
151 
152 struct tcf_ematch_ops;
153 
154 /**
155  * struct tcf_ematch - extended match (ematch)
156  *
157  * @matchid: identifier to allow userspace to reidentify a match
158  * @flags: flags specifying attributes and the relation to other matches
159  * @ops: the operations lookup table of the corresponding ematch module
160  * @datalen: length of the ematch specific configuration data
161  * @data: ematch specific data
162  */
163 struct tcf_ematch {
164 	struct tcf_ematch_ops * ops;
165 	unsigned long		data;
166 	unsigned int		datalen;
167 	u16			matchid;
168 	u16			flags;
169 	struct net		*net;
170 };
171 
172 static inline int tcf_em_is_container(struct tcf_ematch *em)
173 {
174 	return !em->ops;
175 }
176 
177 static inline int tcf_em_is_simple(struct tcf_ematch *em)
178 {
179 	return em->flags & TCF_EM_SIMPLE;
180 }
181 
182 static inline int tcf_em_is_inverted(struct tcf_ematch *em)
183 {
184 	return em->flags & TCF_EM_INVERT;
185 }
186 
187 static inline int tcf_em_last_match(struct tcf_ematch *em)
188 {
189 	return (em->flags & TCF_EM_REL_MASK) == TCF_EM_REL_END;
190 }
191 
192 static inline int tcf_em_early_end(struct tcf_ematch *em, int result)
193 {
194 	if (tcf_em_last_match(em))
195 		return 1;
196 
197 	if (result == 0 && em->flags & TCF_EM_REL_AND)
198 		return 1;
199 
200 	if (result != 0 && em->flags & TCF_EM_REL_OR)
201 		return 1;
202 
203 	return 0;
204 }
205 
206 /**
207  * struct tcf_ematch_tree - ematch tree handle
208  *
209  * @hdr: ematch tree header supplied by userspace
210  * @matches: array of ematches
211  */
212 struct tcf_ematch_tree {
213 	struct tcf_ematch_tree_hdr hdr;
214 	struct tcf_ematch *	matches;
215 
216 };
217 
218 /**
219  * struct tcf_ematch_ops - ematch module operations
220  *
221  * @kind: identifier (kind) of this ematch module
222  * @datalen: length of expected configuration data (optional)
223  * @change: called during validation (optional)
224  * @match: called during ematch tree evaluation, must return 1/0
225  * @destroy: called during destroyage (optional)
226  * @dump: called during dumping process (optional)
227  * @owner: owner, must be set to THIS_MODULE
228  * @link: link to previous/next ematch module (internal use)
229  */
230 struct tcf_ematch_ops {
231 	int			kind;
232 	int			datalen;
233 	int			(*change)(struct net *net, void *,
234 					  int, struct tcf_ematch *);
235 	int			(*match)(struct sk_buff *, struct tcf_ematch *,
236 					 struct tcf_pkt_info *);
237 	void			(*destroy)(struct tcf_ematch *);
238 	int			(*dump)(struct sk_buff *, struct tcf_ematch *);
239 	struct module		*owner;
240 	struct list_head	link;
241 };
242 
243 int tcf_em_register(struct tcf_ematch_ops *);
244 void tcf_em_unregister(struct tcf_ematch_ops *);
245 int tcf_em_tree_validate(struct tcf_proto *, struct nlattr *,
246 			 struct tcf_ematch_tree *);
247 void tcf_em_tree_destroy(struct tcf_ematch_tree *);
248 int tcf_em_tree_dump(struct sk_buff *, struct tcf_ematch_tree *, int);
249 int __tcf_em_tree_match(struct sk_buff *, struct tcf_ematch_tree *,
250 			struct tcf_pkt_info *);
251 
252 /**
253  * tcf_em_tree_change - replace ematch tree of a running classifier
254  *
255  * @tp: classifier kind handle
256  * @dst: destination ematch tree variable
257  * @src: source ematch tree (temporary tree from tcf_em_tree_validate)
258  *
259  * This functions replaces the ematch tree in @dst with the ematch
260  * tree in @src. The classifier in charge of the ematch tree may be
261  * running.
262  */
263 static inline void tcf_em_tree_change(struct tcf_proto *tp,
264 				      struct tcf_ematch_tree *dst,
265 				      struct tcf_ematch_tree *src)
266 {
267 	tcf_tree_lock(tp);
268 	memcpy(dst, src, sizeof(*dst));
269 	tcf_tree_unlock(tp);
270 }
271 
272 /**
273  * tcf_em_tree_match - evaulate an ematch tree
274  *
275  * @skb: socket buffer of the packet in question
276  * @tree: ematch tree to be used for evaluation
277  * @info: packet information examined by classifier
278  *
279  * This function matches @skb against the ematch tree in @tree by going
280  * through all ematches respecting their logic relations returning
281  * as soon as the result is obvious.
282  *
283  * Returns 1 if the ematch tree as-one matches, no ematches are configured
284  * or ematch is not enabled in the kernel, otherwise 0 is returned.
285  */
286 static inline int tcf_em_tree_match(struct sk_buff *skb,
287 				    struct tcf_ematch_tree *tree,
288 				    struct tcf_pkt_info *info)
289 {
290 	if (tree->hdr.nmatches)
291 		return __tcf_em_tree_match(skb, tree, info);
292 	else
293 		return 1;
294 }
295 
296 #define MODULE_ALIAS_TCF_EMATCH(kind)	MODULE_ALIAS("ematch-kind-" __stringify(kind))
297 
298 #else /* CONFIG_NET_EMATCH */
299 
300 struct tcf_ematch_tree {
301 };
302 
303 #define tcf_em_tree_validate(tp, tb, t) ((void)(t), 0)
304 #define tcf_em_tree_destroy(t) do { (void)(t); } while(0)
305 #define tcf_em_tree_dump(skb, t, tlv) (0)
306 #define tcf_em_tree_change(tp, dst, src) do { } while(0)
307 #define tcf_em_tree_match(skb, t, info) ((void)(info), 1)
308 
309 #endif /* CONFIG_NET_EMATCH */
310 
311 static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
312 {
313 	switch (layer) {
314 		case TCF_LAYER_LINK:
315 			return skb->data;
316 		case TCF_LAYER_NETWORK:
317 			return skb_network_header(skb);
318 		case TCF_LAYER_TRANSPORT:
319 			return skb_transport_header(skb);
320 	}
321 
322 	return NULL;
323 }
324 
325 static inline int tcf_valid_offset(const struct sk_buff *skb,
326 				   const unsigned char *ptr, const int len)
327 {
328 	return likely((ptr + len) <= skb_tail_pointer(skb) &&
329 		      ptr >= skb->head &&
330 		      (ptr <= (ptr + len)));
331 }
332 
333 #ifdef CONFIG_NET_CLS_IND
334 #include <net/net_namespace.h>
335 
336 static inline int
337 tcf_change_indev(struct net *net, struct nlattr *indev_tlv)
338 {
339 	char indev[IFNAMSIZ];
340 	struct net_device *dev;
341 
342 	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ)
343 		return -EINVAL;
344 	dev = __dev_get_by_name(net, indev);
345 	if (!dev)
346 		return -ENODEV;
347 	return dev->ifindex;
348 }
349 
350 static inline bool
351 tcf_match_indev(struct sk_buff *skb, int ifindex)
352 {
353 	if (!ifindex)
354 		return true;
355 	if  (!skb->skb_iif)
356 		return false;
357 	return ifindex == skb->skb_iif;
358 }
359 #endif /* CONFIG_NET_CLS_IND */
360 
361 struct tc_cls_u32_knode {
362 	struct tcf_exts *exts;
363 	struct tc_u32_sel *sel;
364 	u32 handle;
365 	u32 val;
366 	u32 mask;
367 	u32 link_handle;
368 	u8 fshift;
369 };
370 
371 struct tc_cls_u32_hnode {
372 	u32 handle;
373 	u32 prio;
374 	unsigned int divisor;
375 };
376 
377 enum tc_clsu32_command {
378 	TC_CLSU32_NEW_KNODE,
379 	TC_CLSU32_REPLACE_KNODE,
380 	TC_CLSU32_DELETE_KNODE,
381 	TC_CLSU32_NEW_HNODE,
382 	TC_CLSU32_REPLACE_HNODE,
383 	TC_CLSU32_DELETE_HNODE,
384 };
385 
386 struct tc_cls_u32_offload {
387 	/* knode values */
388 	enum tc_clsu32_command command;
389 	union {
390 		struct tc_cls_u32_knode knode;
391 		struct tc_cls_u32_hnode hnode;
392 	};
393 };
394 
395 static inline bool tc_should_offload(const struct net_device *dev,
396 				     const struct tcf_proto *tp, u32 flags)
397 {
398 	const struct Qdisc *sch = tp->q;
399 	const struct Qdisc_class_ops *cops = sch->ops->cl_ops;
400 
401 	if (!(dev->features & NETIF_F_HW_TC))
402 		return false;
403 	if (flags & TCA_CLS_FLAGS_SKIP_HW)
404 		return false;
405 	if (!dev->netdev_ops->ndo_setup_tc)
406 		return false;
407 	if (cops && cops->tcf_cl_offload)
408 		return cops->tcf_cl_offload(tp->classid);
409 
410 	return true;
411 }
412 
413 static inline bool tc_skip_sw(u32 flags)
414 {
415 	return (flags & TCA_CLS_FLAGS_SKIP_SW) ? true : false;
416 }
417 
418 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
419 static inline bool tc_flags_valid(u32 flags)
420 {
421 	if (flags & ~(TCA_CLS_FLAGS_SKIP_HW | TCA_CLS_FLAGS_SKIP_SW))
422 		return false;
423 
424 	if (!(flags ^ (TCA_CLS_FLAGS_SKIP_HW | TCA_CLS_FLAGS_SKIP_SW)))
425 		return false;
426 
427 	return true;
428 }
429 
430 enum tc_fl_command {
431 	TC_CLSFLOWER_REPLACE,
432 	TC_CLSFLOWER_DESTROY,
433 	TC_CLSFLOWER_STATS,
434 };
435 
436 struct tc_cls_flower_offload {
437 	enum tc_fl_command command;
438 	unsigned long cookie;
439 	struct flow_dissector *dissector;
440 	struct fl_flow_key *mask;
441 	struct fl_flow_key *key;
442 	struct tcf_exts *exts;
443 };
444 
445 #endif
446