xref: /linux/include/net/pkt_cls.h (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 extern int register_tcf_proto_ops(struct tcf_proto_ops *ops);
18 extern 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 	unsigned long old_cl;
24 
25 	old_cl = *clp;
26 	*clp = cl;
27 	return old_cl;
28 }
29 
30 static inline unsigned long
31 cls_set_class(struct tcf_proto *tp, unsigned long *clp,
32 	unsigned long cl)
33 {
34 	unsigned long old_cl;
35 
36 	tcf_tree_lock(tp);
37 	old_cl = __cls_set_class(clp, cl);
38 	tcf_tree_unlock(tp);
39 
40 	return old_cl;
41 }
42 
43 static inline void
44 tcf_bind_filter(struct tcf_proto *tp, struct tcf_result *r, unsigned long base)
45 {
46 	unsigned long cl;
47 
48 	cl = tp->q->ops->cl_ops->bind_tcf(tp->q, base, r->classid);
49 	cl = cls_set_class(tp, &r->class, cl);
50 	if (cl)
51 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
52 }
53 
54 static inline void
55 tcf_unbind_filter(struct tcf_proto *tp, struct tcf_result *r)
56 {
57 	unsigned long cl;
58 
59 	if ((cl = __cls_set_class(&r->class, 0)) != 0)
60 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
61 }
62 
63 struct tcf_exts {
64 #ifdef CONFIG_NET_CLS_ACT
65 	struct tc_action *action;
66 #endif
67 };
68 
69 /* Map to export classifier specific extension TLV types to the
70  * generic extensions API. Unsupported extensions must be set to 0.
71  */
72 struct tcf_ext_map {
73 	int action;
74 	int police;
75 };
76 
77 /**
78  * tcf_exts_is_predicative - check if a predicative extension is present
79  * @exts: tc filter extensions handle
80  *
81  * Returns 1 if a predicative extension is present, i.e. an extension which
82  * might cause further actions and thus overrule the regular tcf_result.
83  */
84 static inline int
85 tcf_exts_is_predicative(struct tcf_exts *exts)
86 {
87 #ifdef CONFIG_NET_CLS_ACT
88 	return !!exts->action;
89 #else
90 	return 0;
91 #endif
92 }
93 
94 /**
95  * tcf_exts_is_available - check if at least one extension is present
96  * @exts: tc filter extensions handle
97  *
98  * Returns 1 if at least one extension is present.
99  */
100 static inline int
101 tcf_exts_is_available(struct tcf_exts *exts)
102 {
103 	/* All non-predicative extensions must be added here. */
104 	return tcf_exts_is_predicative(exts);
105 }
106 
107 /**
108  * tcf_exts_exec - execute tc filter extensions
109  * @skb: socket buffer
110  * @exts: tc filter extensions handle
111  * @res: desired result
112  *
113  * Executes all configured extensions. Returns 0 on a normal execution,
114  * a negative number if the filter must be considered unmatched or
115  * a positive action code (TC_ACT_*) which must be returned to the
116  * underlying layer.
117  */
118 static inline int
119 tcf_exts_exec(struct sk_buff *skb, struct tcf_exts *exts,
120 	       struct tcf_result *res)
121 {
122 #ifdef CONFIG_NET_CLS_ACT
123 	if (exts->action)
124 		return tcf_action_exec(skb, exts->action, res);
125 #endif
126 	return 0;
127 }
128 
129 extern int tcf_exts_validate(struct tcf_proto *tp, struct nlattr **tb,
130 	                     struct nlattr *rate_tlv, struct tcf_exts *exts,
131 	                     const struct tcf_ext_map *map);
132 extern void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts);
133 extern void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
134 	                     struct tcf_exts *src);
135 extern int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
136 	                 const struct tcf_ext_map *map);
137 extern int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
138 	                       const struct tcf_ext_map *map);
139 
140 /**
141  * struct tcf_pkt_info - packet information
142  */
143 struct tcf_pkt_info {
144 	unsigned char *		ptr;
145 	int			nexthdr;
146 };
147 
148 #ifdef CONFIG_NET_EMATCH
149 
150 struct tcf_ematch_ops;
151 
152 /**
153  * struct tcf_ematch - extended match (ematch)
154  *
155  * @matchid: identifier to allow userspace to reidentify a match
156  * @flags: flags specifying attributes and the relation to other matches
157  * @ops: the operations lookup table of the corresponding ematch module
158  * @datalen: length of the ematch specific configuration data
159  * @data: ematch specific data
160  */
161 struct tcf_ematch {
162 	struct tcf_ematch_ops * ops;
163 	unsigned long		data;
164 	unsigned int		datalen;
165 	u16			matchid;
166 	u16			flags;
167 };
168 
169 static inline int tcf_em_is_container(struct tcf_ematch *em)
170 {
171 	return !em->ops;
172 }
173 
174 static inline int tcf_em_is_simple(struct tcf_ematch *em)
175 {
176 	return em->flags & TCF_EM_SIMPLE;
177 }
178 
179 static inline int tcf_em_is_inverted(struct tcf_ematch *em)
180 {
181 	return em->flags & TCF_EM_INVERT;
182 }
183 
184 static inline int tcf_em_last_match(struct tcf_ematch *em)
185 {
186 	return (em->flags & TCF_EM_REL_MASK) == TCF_EM_REL_END;
187 }
188 
189 static inline int tcf_em_early_end(struct tcf_ematch *em, int result)
190 {
191 	if (tcf_em_last_match(em))
192 		return 1;
193 
194 	if (result == 0 && em->flags & TCF_EM_REL_AND)
195 		return 1;
196 
197 	if (result != 0 && em->flags & TCF_EM_REL_OR)
198 		return 1;
199 
200 	return 0;
201 }
202 
203 /**
204  * struct tcf_ematch_tree - ematch tree handle
205  *
206  * @hdr: ematch tree header supplied by userspace
207  * @matches: array of ematches
208  */
209 struct tcf_ematch_tree {
210 	struct tcf_ematch_tree_hdr hdr;
211 	struct tcf_ematch *	matches;
212 
213 };
214 
215 /**
216  * struct tcf_ematch_ops - ematch module operations
217  *
218  * @kind: identifier (kind) of this ematch module
219  * @datalen: length of expected configuration data (optional)
220  * @change: called during validation (optional)
221  * @match: called during ematch tree evaluation, must return 1/0
222  * @destroy: called during destroyage (optional)
223  * @dump: called during dumping process (optional)
224  * @owner: owner, must be set to THIS_MODULE
225  * @link: link to previous/next ematch module (internal use)
226  */
227 struct tcf_ematch_ops {
228 	int			kind;
229 	int			datalen;
230 	int			(*change)(struct tcf_proto *, void *,
231 					  int, struct tcf_ematch *);
232 	int			(*match)(struct sk_buff *, struct tcf_ematch *,
233 					 struct tcf_pkt_info *);
234 	void			(*destroy)(struct tcf_proto *,
235 					   struct tcf_ematch *);
236 	int			(*dump)(struct sk_buff *, struct tcf_ematch *);
237 	struct module		*owner;
238 	struct list_head	link;
239 };
240 
241 extern int tcf_em_register(struct tcf_ematch_ops *);
242 extern void tcf_em_unregister(struct tcf_ematch_ops *);
243 extern int tcf_em_tree_validate(struct tcf_proto *, struct nlattr *,
244 				struct tcf_ematch_tree *);
245 extern void tcf_em_tree_destroy(struct tcf_proto *, struct tcf_ematch_tree *);
246 extern int tcf_em_tree_dump(struct sk_buff *, struct tcf_ematch_tree *, int);
247 extern int __tcf_em_tree_match(struct sk_buff *, struct tcf_ematch_tree *,
248 			       struct tcf_pkt_info *);
249 
250 /**
251  * tcf_em_tree_change - replace ematch tree of a running classifier
252  *
253  * @tp: classifier kind handle
254  * @dst: destination ematch tree variable
255  * @src: source ematch tree (temporary tree from tcf_em_tree_validate)
256  *
257  * This functions replaces the ematch tree in @dst with the ematch
258  * tree in @src. The classifier in charge of the ematch tree may be
259  * running.
260  */
261 static inline void tcf_em_tree_change(struct tcf_proto *tp,
262 				      struct tcf_ematch_tree *dst,
263 				      struct tcf_ematch_tree *src)
264 {
265 	tcf_tree_lock(tp);
266 	memcpy(dst, src, sizeof(*dst));
267 	tcf_tree_unlock(tp);
268 }
269 
270 /**
271  * tcf_em_tree_match - evaulate an ematch tree
272  *
273  * @skb: socket buffer of the packet in question
274  * @tree: ematch tree to be used for evaluation
275  * @info: packet information examined by classifier
276  *
277  * This function matches @skb against the ematch tree in @tree by going
278  * through all ematches respecting their logic relations returning
279  * as soon as the result is obvious.
280  *
281  * Returns 1 if the ematch tree as-one matches, no ematches are configured
282  * or ematch is not enabled in the kernel, otherwise 0 is returned.
283  */
284 static inline int tcf_em_tree_match(struct sk_buff *skb,
285 				    struct tcf_ematch_tree *tree,
286 				    struct tcf_pkt_info *info)
287 {
288 	if (tree->hdr.nmatches)
289 		return __tcf_em_tree_match(skb, tree, info);
290 	else
291 		return 1;
292 }
293 
294 #define MODULE_ALIAS_TCF_EMATCH(kind)	MODULE_ALIAS("ematch-kind-" __stringify(kind))
295 
296 #else /* CONFIG_NET_EMATCH */
297 
298 struct tcf_ematch_tree {
299 };
300 
301 #define tcf_em_tree_validate(tp, tb, t) ((void)(t), 0)
302 #define tcf_em_tree_destroy(tp, t) do { (void)(t); } while(0)
303 #define tcf_em_tree_dump(skb, t, tlv) (0)
304 #define tcf_em_tree_change(tp, dst, src) do { } while(0)
305 #define tcf_em_tree_match(skb, t, info) ((void)(info), 1)
306 
307 #endif /* CONFIG_NET_EMATCH */
308 
309 static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
310 {
311 	switch (layer) {
312 		case TCF_LAYER_LINK:
313 			return skb->data;
314 		case TCF_LAYER_NETWORK:
315 			return skb_network_header(skb);
316 		case TCF_LAYER_TRANSPORT:
317 			return skb_transport_header(skb);
318 	}
319 
320 	return NULL;
321 }
322 
323 static inline int tcf_valid_offset(const struct sk_buff *skb,
324 				   const unsigned char *ptr, const int len)
325 {
326 	return likely((ptr + len) <= skb_tail_pointer(skb) &&
327 		      ptr >= skb->head &&
328 		      (ptr <= (ptr + len)));
329 }
330 
331 #ifdef CONFIG_NET_CLS_IND
332 #include <net/net_namespace.h>
333 
334 static inline int
335 tcf_change_indev(struct tcf_proto *tp, char *indev, struct nlattr *indev_tlv)
336 {
337 	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ)
338 		return -EINVAL;
339 	return 0;
340 }
341 
342 static inline int
343 tcf_match_indev(struct sk_buff *skb, char *indev)
344 {
345 	struct net_device *dev;
346 
347 	if (indev[0]) {
348 		if  (!skb->skb_iif)
349 			return 0;
350 		dev = __dev_get_by_index(dev_net(skb->dev), skb->skb_iif);
351 		if (!dev || strcmp(indev, dev->name))
352 			return 0;
353 	}
354 
355 	return 1;
356 }
357 #endif /* CONFIG_NET_CLS_IND */
358 
359 #endif
360