xref: /linux/include/net/pkt_cls.h (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
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 {
12 	int	stop;
13 	int	skip;
14 	int	count;
15 	int	(*fn)(struct tcf_proto *, unsigned long node, struct tcf_walker *);
16 };
17 
18 extern int register_tcf_proto_ops(struct tcf_proto_ops *ops);
19 extern int unregister_tcf_proto_ops(struct tcf_proto_ops *ops);
20 
21 static inline unsigned long
22 __cls_set_class(unsigned long *clp, unsigned long cl)
23 {
24 	unsigned long old_cl;
25 
26 	old_cl = *clp;
27 	*clp = cl;
28 	return old_cl;
29 }
30 
31 static inline unsigned long
32 cls_set_class(struct tcf_proto *tp, unsigned long *clp,
33 	unsigned long cl)
34 {
35 	unsigned long old_cl;
36 
37 	tcf_tree_lock(tp);
38 	old_cl = __cls_set_class(clp, cl);
39 	tcf_tree_unlock(tp);
40 
41 	return old_cl;
42 }
43 
44 static inline void
45 tcf_bind_filter(struct tcf_proto *tp, struct tcf_result *r, unsigned long base)
46 {
47 	unsigned long cl;
48 
49 	cl = tp->q->ops->cl_ops->bind_tcf(tp->q, base, r->classid);
50 	cl = cls_set_class(tp, &r->class, cl);
51 	if (cl)
52 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
53 }
54 
55 static inline void
56 tcf_unbind_filter(struct tcf_proto *tp, struct tcf_result *r)
57 {
58 	unsigned long cl;
59 
60 	if ((cl = __cls_set_class(&r->class, 0)) != 0)
61 		tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
62 }
63 
64 struct tcf_exts
65 {
66 #ifdef CONFIG_NET_CLS_ACT
67 	struct tc_action *action;
68 #endif
69 };
70 
71 /* Map to export classifier specific extension TLV types to the
72  * generic extensions API. Unsupported extensions must be set to 0.
73  */
74 struct tcf_ext_map
75 {
76 	int action;
77 	int police;
78 };
79 
80 /**
81  * tcf_exts_is_predicative - check if a predicative extension is present
82  * @exts: tc filter extensions handle
83  *
84  * Returns 1 if a predicative extension is present, i.e. an extension which
85  * might cause further actions and thus overrule the regular tcf_result.
86  */
87 static inline int
88 tcf_exts_is_predicative(struct tcf_exts *exts)
89 {
90 #ifdef CONFIG_NET_CLS_ACT
91 	return !!exts->action;
92 #else
93 	return 0;
94 #endif
95 }
96 
97 /**
98  * tcf_exts_is_available - check if at least one extension is present
99  * @exts: tc filter extensions handle
100  *
101  * Returns 1 if at least one extension is present.
102  */
103 static inline int
104 tcf_exts_is_available(struct tcf_exts *exts)
105 {
106 	/* All non-predicative extensions must be added here. */
107 	return tcf_exts_is_predicative(exts);
108 }
109 
110 /**
111  * tcf_exts_exec - execute tc filter extensions
112  * @skb: socket buffer
113  * @exts: tc filter extensions handle
114  * @res: desired result
115  *
116  * Executes all configured extensions. Returns 0 on a normal execution,
117  * a negative number if the filter must be considered unmatched or
118  * a positive action code (TC_ACT_*) which must be returned to the
119  * underlying layer.
120  */
121 static inline int
122 tcf_exts_exec(struct sk_buff *skb, struct tcf_exts *exts,
123 	       struct tcf_result *res)
124 {
125 #ifdef CONFIG_NET_CLS_ACT
126 	if (exts->action)
127 		return tcf_action_exec(skb, exts->action, res);
128 #endif
129 	return 0;
130 }
131 
132 extern int tcf_exts_validate(struct tcf_proto *tp, struct nlattr **tb,
133 	                     struct nlattr *rate_tlv, struct tcf_exts *exts,
134 	                     const struct tcf_ext_map *map);
135 extern void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts);
136 extern void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
137 	                     struct tcf_exts *src);
138 extern int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
139 	                 const struct tcf_ext_map *map);
140 extern int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
141 	                       const struct tcf_ext_map *map);
142 
143 /**
144  * struct tcf_pkt_info - packet information
145  */
146 struct tcf_pkt_info
147 {
148 	unsigned char *		ptr;
149 	int			nexthdr;
150 };
151 
152 #ifdef CONFIG_NET_EMATCH
153 
154 struct tcf_ematch_ops;
155 
156 /**
157  * struct tcf_ematch - extended match (ematch)
158  *
159  * @matchid: identifier to allow userspace to reidentify a match
160  * @flags: flags specifying attributes and the relation to other matches
161  * @ops: the operations lookup table of the corresponding ematch module
162  * @datalen: length of the ematch specific configuration data
163  * @data: ematch specific data
164  */
165 struct tcf_ematch
166 {
167 	struct tcf_ematch_ops * ops;
168 	unsigned long		data;
169 	unsigned int		datalen;
170 	u16			matchid;
171 	u16			flags;
172 };
173 
174 static inline int tcf_em_is_container(struct tcf_ematch *em)
175 {
176 	return !em->ops;
177 }
178 
179 static inline int tcf_em_is_simple(struct tcf_ematch *em)
180 {
181 	return em->flags & TCF_EM_SIMPLE;
182 }
183 
184 static inline int tcf_em_is_inverted(struct tcf_ematch *em)
185 {
186 	return em->flags & TCF_EM_INVERT;
187 }
188 
189 static inline int tcf_em_last_match(struct tcf_ematch *em)
190 {
191 	return (em->flags & TCF_EM_REL_MASK) == TCF_EM_REL_END;
192 }
193 
194 static inline int tcf_em_early_end(struct tcf_ematch *em, int result)
195 {
196 	if (tcf_em_last_match(em))
197 		return 1;
198 
199 	if (result == 0 && em->flags & TCF_EM_REL_AND)
200 		return 1;
201 
202 	if (result != 0 && em->flags & TCF_EM_REL_OR)
203 		return 1;
204 
205 	return 0;
206 }
207 
208 /**
209  * struct tcf_ematch_tree - ematch tree handle
210  *
211  * @hdr: ematch tree header supplied by userspace
212  * @matches: array of ematches
213  */
214 struct tcf_ematch_tree
215 {
216 	struct tcf_ematch_tree_hdr hdr;
217 	struct tcf_ematch *	matches;
218 
219 };
220 
221 /**
222  * struct tcf_ematch_ops - ematch module operations
223  *
224  * @kind: identifier (kind) of this ematch module
225  * @datalen: length of expected configuration data (optional)
226  * @change: called during validation (optional)
227  * @match: called during ematch tree evaluation, must return 1/0
228  * @destroy: called during destroyage (optional)
229  * @dump: called during dumping process (optional)
230  * @owner: owner, must be set to THIS_MODULE
231  * @link: link to previous/next ematch module (internal use)
232  */
233 struct tcf_ematch_ops
234 {
235 	int			kind;
236 	int			datalen;
237 	int			(*change)(struct tcf_proto *, void *,
238 					  int, struct tcf_ematch *);
239 	int			(*match)(struct sk_buff *, struct tcf_ematch *,
240 					 struct tcf_pkt_info *);
241 	void			(*destroy)(struct tcf_proto *,
242 					   struct tcf_ematch *);
243 	int			(*dump)(struct sk_buff *, struct tcf_ematch *);
244 	struct module		*owner;
245 	struct list_head	link;
246 };
247 
248 extern int tcf_em_register(struct tcf_ematch_ops *);
249 extern void tcf_em_unregister(struct tcf_ematch_ops *);
250 extern int tcf_em_tree_validate(struct tcf_proto *, struct nlattr *,
251 				struct tcf_ematch_tree *);
252 extern void tcf_em_tree_destroy(struct tcf_proto *, struct tcf_ematch_tree *);
253 extern int tcf_em_tree_dump(struct sk_buff *, struct tcf_ematch_tree *, int);
254 extern int __tcf_em_tree_match(struct sk_buff *, struct tcf_ematch_tree *,
255 			       struct tcf_pkt_info *);
256 
257 /**
258  * tcf_em_tree_change - replace ematch tree of a running classifier
259  *
260  * @tp: classifier kind handle
261  * @dst: destination ematch tree variable
262  * @src: source ematch tree (temporary tree from tcf_em_tree_validate)
263  *
264  * This functions replaces the ematch tree in @dst with the ematch
265  * tree in @src. The classifier in charge of the ematch tree may be
266  * running.
267  */
268 static inline void tcf_em_tree_change(struct tcf_proto *tp,
269 				      struct tcf_ematch_tree *dst,
270 				      struct tcf_ematch_tree *src)
271 {
272 	tcf_tree_lock(tp);
273 	memcpy(dst, src, sizeof(*dst));
274 	tcf_tree_unlock(tp);
275 }
276 
277 /**
278  * tcf_em_tree_match - evaulate an ematch tree
279  *
280  * @skb: socket buffer of the packet in question
281  * @tree: ematch tree to be used for evaluation
282  * @info: packet information examined by classifier
283  *
284  * This function matches @skb against the ematch tree in @tree by going
285  * through all ematches respecting their logic relations returning
286  * as soon as the result is obvious.
287  *
288  * Returns 1 if the ematch tree as-one matches, no ematches are configured
289  * or ematch is not enabled in the kernel, otherwise 0 is returned.
290  */
291 static inline int tcf_em_tree_match(struct sk_buff *skb,
292 				    struct tcf_ematch_tree *tree,
293 				    struct tcf_pkt_info *info)
294 {
295 	if (tree->hdr.nmatches)
296 		return __tcf_em_tree_match(skb, tree, info);
297 	else
298 		return 1;
299 }
300 
301 #define MODULE_ALIAS_TCF_EMATCH(kind)	MODULE_ALIAS("ematch-kind-" __stringify(kind))
302 
303 #else /* CONFIG_NET_EMATCH */
304 
305 struct tcf_ematch_tree
306 {
307 };
308 
309 #define tcf_em_tree_validate(tp, tb, t) ((void)(t), 0)
310 #define tcf_em_tree_destroy(tp, t) do { (void)(t); } while(0)
311 #define tcf_em_tree_dump(skb, t, tlv) (0)
312 #define tcf_em_tree_change(tp, dst, src) do { } while(0)
313 #define tcf_em_tree_match(skb, t, info) ((void)(info), 1)
314 
315 #endif /* CONFIG_NET_EMATCH */
316 
317 static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
318 {
319 	switch (layer) {
320 		case TCF_LAYER_LINK:
321 			return skb->data;
322 		case TCF_LAYER_NETWORK:
323 			return skb_network_header(skb);
324 		case TCF_LAYER_TRANSPORT:
325 			return skb_transport_header(skb);
326 	}
327 
328 	return NULL;
329 }
330 
331 static inline int tcf_valid_offset(const struct sk_buff *skb,
332 				   const unsigned char *ptr, const int len)
333 {
334 	return unlikely((ptr + len) < skb_tail_pointer(skb) && ptr > skb->head);
335 }
336 
337 #ifdef CONFIG_NET_CLS_IND
338 #include <net/net_namespace.h>
339 
340 static inline int
341 tcf_change_indev(struct tcf_proto *tp, char *indev, struct nlattr *indev_tlv)
342 {
343 	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ)
344 		return -EINVAL;
345 	return 0;
346 }
347 
348 static inline int
349 tcf_match_indev(struct sk_buff *skb, char *indev)
350 {
351 	struct net_device *dev;
352 
353 	if (indev[0]) {
354 		if  (!skb->iif)
355 			return 0;
356 		dev = __dev_get_by_index(dev_net(skb->dev), skb->iif);
357 		if (!dev || strcmp(indev, dev->name))
358 			return 0;
359 	}
360 
361 	return 1;
362 }
363 #endif /* CONFIG_NET_CLS_IND */
364 
365 #endif
366