xref: /openbmc/linux/include/net/pkt_cls.h (revision 37be287c)
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 	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 	__u32	type; /* for backward compat(TCA_OLD_COMPAT) */
66 	struct list_head actions;
67 #endif
68 	/* Map to export classifier specific extension TLV types to the
69 	 * generic extensions API. Unsupported extensions must be set to 0.
70 	 */
71 	int action;
72 	int police;
73 };
74 
75 static inline void tcf_exts_init(struct tcf_exts *exts, int action, int police)
76 {
77 #ifdef CONFIG_NET_CLS_ACT
78 	exts->type = 0;
79 	INIT_LIST_HEAD(&exts->actions);
80 #endif
81 	exts->action = action;
82 	exts->police = police;
83 }
84 
85 /**
86  * tcf_exts_is_predicative - check if a predicative extension is present
87  * @exts: tc filter extensions handle
88  *
89  * Returns 1 if a predicative extension is present, i.e. an extension which
90  * might cause further actions and thus overrule the regular tcf_result.
91  */
92 static inline int
93 tcf_exts_is_predicative(struct tcf_exts *exts)
94 {
95 #ifdef CONFIG_NET_CLS_ACT
96 	return !list_empty(&exts->actions);
97 #else
98 	return 0;
99 #endif
100 }
101 
102 /**
103  * tcf_exts_is_available - check if at least one extension is present
104  * @exts: tc filter extensions handle
105  *
106  * Returns 1 if at least one extension is present.
107  */
108 static inline int
109 tcf_exts_is_available(struct tcf_exts *exts)
110 {
111 	/* All non-predicative extensions must be added here. */
112 	return tcf_exts_is_predicative(exts);
113 }
114 
115 /**
116  * tcf_exts_exec - execute tc filter extensions
117  * @skb: socket buffer
118  * @exts: tc filter extensions handle
119  * @res: desired result
120  *
121  * Executes all configured extensions. Returns 0 on a normal execution,
122  * a negative number if the filter must be considered unmatched or
123  * a positive action code (TC_ACT_*) which must be returned to the
124  * underlying layer.
125  */
126 static inline int
127 tcf_exts_exec(struct sk_buff *skb, struct tcf_exts *exts,
128 	       struct tcf_result *res)
129 {
130 #ifdef CONFIG_NET_CLS_ACT
131 	if (!list_empty(&exts->actions))
132 		return tcf_action_exec(skb, &exts->actions, res);
133 #endif
134 	return 0;
135 }
136 
137 int tcf_exts_validate(struct net *net, struct tcf_proto *tp,
138 		      struct nlattr **tb, struct nlattr *rate_tlv,
139 		      struct tcf_exts *exts);
140 void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts);
141 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
142 		     struct tcf_exts *src);
143 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts);
144 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts);
145 
146 /**
147  * struct tcf_pkt_info - packet information
148  */
149 struct tcf_pkt_info {
150 	unsigned char *		ptr;
151 	int			nexthdr;
152 };
153 
154 #ifdef CONFIG_NET_EMATCH
155 
156 struct tcf_ematch_ops;
157 
158 /**
159  * struct tcf_ematch - extended match (ematch)
160  *
161  * @matchid: identifier to allow userspace to reidentify a match
162  * @flags: flags specifying attributes and the relation to other matches
163  * @ops: the operations lookup table of the corresponding ematch module
164  * @datalen: length of the ematch specific configuration data
165  * @data: ematch specific data
166  */
167 struct tcf_ematch {
168 	struct tcf_ematch_ops * ops;
169 	unsigned long		data;
170 	unsigned int		datalen;
171 	u16			matchid;
172 	u16			flags;
173 };
174 
175 static inline int tcf_em_is_container(struct tcf_ematch *em)
176 {
177 	return !em->ops;
178 }
179 
180 static inline int tcf_em_is_simple(struct tcf_ematch *em)
181 {
182 	return em->flags & TCF_EM_SIMPLE;
183 }
184 
185 static inline int tcf_em_is_inverted(struct tcf_ematch *em)
186 {
187 	return em->flags & TCF_EM_INVERT;
188 }
189 
190 static inline int tcf_em_last_match(struct tcf_ematch *em)
191 {
192 	return (em->flags & TCF_EM_REL_MASK) == TCF_EM_REL_END;
193 }
194 
195 static inline int tcf_em_early_end(struct tcf_ematch *em, int result)
196 {
197 	if (tcf_em_last_match(em))
198 		return 1;
199 
200 	if (result == 0 && em->flags & TCF_EM_REL_AND)
201 		return 1;
202 
203 	if (result != 0 && em->flags & TCF_EM_REL_OR)
204 		return 1;
205 
206 	return 0;
207 }
208 
209 /**
210  * struct tcf_ematch_tree - ematch tree handle
211  *
212  * @hdr: ematch tree header supplied by userspace
213  * @matches: array of ematches
214  */
215 struct tcf_ematch_tree {
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 	int			kind;
235 	int			datalen;
236 	int			(*change)(struct tcf_proto *, void *,
237 					  int, struct tcf_ematch *);
238 	int			(*match)(struct sk_buff *, struct tcf_ematch *,
239 					 struct tcf_pkt_info *);
240 	void			(*destroy)(struct tcf_proto *,
241 					   struct tcf_ematch *);
242 	int			(*dump)(struct sk_buff *, struct tcf_ematch *);
243 	struct module		*owner;
244 	struct list_head	link;
245 };
246 
247 int tcf_em_register(struct tcf_ematch_ops *);
248 void tcf_em_unregister(struct tcf_ematch_ops *);
249 int tcf_em_tree_validate(struct tcf_proto *, struct nlattr *,
250 			 struct tcf_ematch_tree *);
251 void tcf_em_tree_destroy(struct tcf_proto *, struct tcf_ematch_tree *);
252 int tcf_em_tree_dump(struct sk_buff *, struct tcf_ematch_tree *, int);
253 int __tcf_em_tree_match(struct sk_buff *, struct tcf_ematch_tree *,
254 			struct tcf_pkt_info *);
255 
256 /**
257  * tcf_em_tree_change - replace ematch tree of a running classifier
258  *
259  * @tp: classifier kind handle
260  * @dst: destination ematch tree variable
261  * @src: source ematch tree (temporary tree from tcf_em_tree_validate)
262  *
263  * This functions replaces the ematch tree in @dst with the ematch
264  * tree in @src. The classifier in charge of the ematch tree may be
265  * running.
266  */
267 static inline void tcf_em_tree_change(struct tcf_proto *tp,
268 				      struct tcf_ematch_tree *dst,
269 				      struct tcf_ematch_tree *src)
270 {
271 	tcf_tree_lock(tp);
272 	memcpy(dst, src, sizeof(*dst));
273 	tcf_tree_unlock(tp);
274 }
275 
276 /**
277  * tcf_em_tree_match - evaulate an ematch tree
278  *
279  * @skb: socket buffer of the packet in question
280  * @tree: ematch tree to be used for evaluation
281  * @info: packet information examined by classifier
282  *
283  * This function matches @skb against the ematch tree in @tree by going
284  * through all ematches respecting their logic relations returning
285  * as soon as the result is obvious.
286  *
287  * Returns 1 if the ematch tree as-one matches, no ematches are configured
288  * or ematch is not enabled in the kernel, otherwise 0 is returned.
289  */
290 static inline int tcf_em_tree_match(struct sk_buff *skb,
291 				    struct tcf_ematch_tree *tree,
292 				    struct tcf_pkt_info *info)
293 {
294 	if (tree->hdr.nmatches)
295 		return __tcf_em_tree_match(skb, tree, info);
296 	else
297 		return 1;
298 }
299 
300 #define MODULE_ALIAS_TCF_EMATCH(kind)	MODULE_ALIAS("ematch-kind-" __stringify(kind))
301 
302 #else /* CONFIG_NET_EMATCH */
303 
304 struct tcf_ematch_tree {
305 };
306 
307 #define tcf_em_tree_validate(tp, tb, t) ((void)(t), 0)
308 #define tcf_em_tree_destroy(tp, t) do { (void)(t); } while(0)
309 #define tcf_em_tree_dump(skb, t, tlv) (0)
310 #define tcf_em_tree_change(tp, dst, src) do { } while(0)
311 #define tcf_em_tree_match(skb, t, info) ((void)(info), 1)
312 
313 #endif /* CONFIG_NET_EMATCH */
314 
315 static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
316 {
317 	switch (layer) {
318 		case TCF_LAYER_LINK:
319 			return skb->data;
320 		case TCF_LAYER_NETWORK:
321 			return skb_network_header(skb);
322 		case TCF_LAYER_TRANSPORT:
323 			return skb_transport_header(skb);
324 	}
325 
326 	return NULL;
327 }
328 
329 static inline int tcf_valid_offset(const struct sk_buff *skb,
330 				   const unsigned char *ptr, const int len)
331 {
332 	return likely((ptr + len) <= skb_tail_pointer(skb) &&
333 		      ptr >= skb->head &&
334 		      (ptr <= (ptr + len)));
335 }
336 
337 #ifdef CONFIG_NET_CLS_IND
338 #include <net/net_namespace.h>
339 
340 static inline int
341 tcf_change_indev(struct net *net, struct nlattr *indev_tlv)
342 {
343 	char indev[IFNAMSIZ];
344 	struct net_device *dev;
345 
346 	if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ)
347 		return -EINVAL;
348 	dev = __dev_get_by_name(net, indev);
349 	if (!dev)
350 		return -ENODEV;
351 	return dev->ifindex;
352 }
353 
354 static inline bool
355 tcf_match_indev(struct sk_buff *skb, int ifindex)
356 {
357 	if (!ifindex)
358 		return true;
359 	if  (!skb->skb_iif)
360 		return false;
361 	return ifindex == skb->skb_iif;
362 }
363 #endif /* CONFIG_NET_CLS_IND */
364 
365 #endif
366