include/net/pkt_cls.h

   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         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 int tcf_exts_validate(struct net *net, struct tcf_proto *tp,
 130                       struct nlattr **tb, struct nlattr *rate_tlv,
 131                       struct tcf_exts *exts,
 132                       const struct tcf_ext_map *map);
 133 void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts);
 134 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
 135                      struct tcf_exts *src);
 136 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
 137                   const struct tcf_ext_map *map);
 138 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
 139                         const struct tcf_ext_map *map);
 140
 141 /**
 142  * struct tcf_pkt_info - packet information
 143  */
 144 struct tcf_pkt_info {
 145         unsigned char *         ptr;
 146         int                     nexthdr;
 147 };
 148
 149 #ifdef CONFIG_NET_EMATCH
 150
 151 struct tcf_ematch_ops;
 152
 153 /**
 154  * struct tcf_ematch - extended match (ematch)
 155  *
 156  * @matchid: identifier to allow userspace to reidentify a match
 157  * @flags: flags specifying attributes and the relation to other matches
 158  * @ops: the operations lookup table of the corresponding ematch module
 159  * @datalen: length of the ematch specific configuration data
 160  * @data: ematch specific data
 161  */
 162 struct tcf_ematch {
 163         struct tcf_ematch_ops * ops;
 164         unsigned long           data;
 165         unsigned int            datalen;
 166         u16                     matchid;
 167         u16                     flags;
 168 };
 169
 170 static inline int tcf_em_is_container(struct tcf_ematch *em)
 171 {
 172         return !em->ops;
 173 }
 174
 175 static inline int tcf_em_is_simple(struct tcf_ematch *em)
 176 {
 177         return em->flags & TCF_EM_SIMPLE;
 178 }
 179
 180 static inline int tcf_em_is_inverted(struct tcf_ematch *em)
 181 {
 182         return em->flags & TCF_EM_INVERT;
 183 }
 184
 185 static inline int tcf_em_last_match(struct tcf_ematch *em)
 186 {
 187         return (em->flags & TCF_EM_REL_MASK) == TCF_EM_REL_END;
 188 }
 189
 190 static inline int tcf_em_early_end(struct tcf_ematch *em, int result)
 191 {
 192         if (tcf_em_last_match(em))
 193                 return 1;
 194
 195         if (result == 0 && em->flags & TCF_EM_REL_AND)
 196                 return 1;
 197
 198         if (result != 0 && em->flags & TCF_EM_REL_OR)
 199                 return 1;
 200
 201         return 0;
 202 }
 203
 204 /**
 205  * struct tcf_ematch_tree - ematch tree handle
 206  *
 207  * @hdr: ematch tree header supplied by userspace
 208  * @matches: array of ematches
 209  */
 210 struct tcf_ematch_tree {
 211         struct tcf_ematch_tree_hdr hdr;
 212         struct tcf_ematch *     matches;
 213
 214 };
 215
 216 /**
 217  * struct tcf_ematch_ops - ematch module operations
 218  *
 219  * @kind: identifier (kind) of this ematch module
 220  * @datalen: length of expected configuration data (optional)
 221  * @change: called during validation (optional)
 222  * @match: called during ematch tree evaluation, must return 1/0
 223  * @destroy: called during destroyage (optional)
 224  * @dump: called during dumping process (optional)
 225  * @owner: owner, must be set to THIS_MODULE
 226  * @link: link to previous/next ematch module (internal use)
 227  */
 228 struct tcf_ematch_ops {
 229         int                     kind;
 230         int                     datalen;
 231         int                     (*change)(struct tcf_proto *, void *,
 232                                           int, struct tcf_ematch *);
 233         int                     (*match)(struct sk_buff *, struct tcf_ematch *,
 234                                          struct tcf_pkt_info *);
 235         void                    (*destroy)(struct tcf_proto *,
 236                                            struct tcf_ematch *);
 237         int                     (*dump)(struct sk_buff *, struct tcf_ematch *);
 238         struct module           *owner;
 239         struct list_head        link;
 240 };
 241
 242 int tcf_em_register(struct tcf_ematch_ops *);
 243 void tcf_em_unregister(struct tcf_ematch_ops *);
 244 int tcf_em_tree_validate(struct tcf_proto *, struct nlattr *,
 245                          struct tcf_ematch_tree *);
 246 void tcf_em_tree_destroy(struct tcf_proto *, struct tcf_ematch_tree *);
 247 int tcf_em_tree_dump(struct sk_buff *, struct tcf_ematch_tree *, int);
 248 int __tcf_em_tree_match(struct sk_buff *, struct tcf_ematch_tree *,
 249                         struct tcf_pkt_info *);
 250
 251 /**
 252  * tcf_em_tree_change - replace ematch tree of a running classifier
 253  *
 254  * @tp: classifier kind handle
 255  * @dst: destination ematch tree variable
 256  * @src: source ematch tree (temporary tree from tcf_em_tree_validate)
 257  *
 258  * This functions replaces the ematch tree in @dst with the ematch
 259  * tree in @src. The classifier in charge of the ematch tree may be
 260  * running.
 261  */
 262 static inline void tcf_em_tree_change(struct tcf_proto *tp,
 263                                       struct tcf_ematch_tree *dst,
 264                                       struct tcf_ematch_tree *src)
 265 {
 266         tcf_tree_lock(tp);
 267         memcpy(dst, src, sizeof(*dst));
 268         tcf_tree_unlock(tp);
 269 }
 270
 271 /**
 272  * tcf_em_tree_match - evaulate an ematch tree
 273  *
 274  * @skb: socket buffer of the packet in question
 275  * @tree: ematch tree to be used for evaluation
 276  * @info: packet information examined by classifier
 277  *
 278  * This function matches @skb against the ematch tree in @tree by going
 279  * through all ematches respecting their logic relations returning
 280  * as soon as the result is obvious.
 281  *
 282  * Returns 1 if the ematch tree as-one matches, no ematches are configured
 283  * or ematch is not enabled in the kernel, otherwise 0 is returned.
 284  */
 285 static inline int tcf_em_tree_match(struct sk_buff *skb,
 286                                     struct tcf_ematch_tree *tree,
 287                                     struct tcf_pkt_info *info)
 288 {
 289         if (tree->hdr.nmatches)
 290                 return __tcf_em_tree_match(skb, tree, info);
 291         else
 292                 return 1;
 293 }
 294
 295 #define MODULE_ALIAS_TCF_EMATCH(kind)   MODULE_ALIAS("ematch-kind-" __stringify(kind))
 296
 297 #else /* CONFIG_NET_EMATCH */
 298
 299 struct tcf_ematch_tree {
 300 };
 301
 302 #define tcf_em_tree_validate(tp, tb, t) ((void)(t), 0)
 303 #define tcf_em_tree_destroy(tp, t) do { (void)(t); } while(0)
 304 #define tcf_em_tree_dump(skb, t, tlv) (0)
 305 #define tcf_em_tree_change(tp, dst, src) do { } while(0)
 306 #define tcf_em_tree_match(skb, t, info) ((void)(info), 1)
 307
 308 #endif /* CONFIG_NET_EMATCH */
 309
 310 static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
 311 {
 312         switch (layer) {
 313                 case TCF_LAYER_LINK:
 314                         return skb->data;
 315                 case TCF_LAYER_NETWORK:
 316                         return skb_network_header(skb);
 317                 case TCF_LAYER_TRANSPORT:
 318                         return skb_transport_header(skb);
 319         }
 320
 321         return NULL;
 322 }
 323
 324 static inline int tcf_valid_offset(const struct sk_buff *skb,
 325                                    const unsigned char *ptr, const int len)
 326 {
 327         return likely((ptr + len) <= skb_tail_pointer(skb) &&
 328                       ptr >= skb->head &&
 329                       (ptr <= (ptr + len)));
 330 }
 331
 332 #ifdef CONFIG_NET_CLS_IND
 333 #include <net/net_namespace.h>
 334
 335 static inline int
 336 tcf_change_indev(struct tcf_proto *tp, char *indev, struct nlattr *indev_tlv)
 337 {
 338         if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ)
 339                 return -EINVAL;
 340         return 0;
 341 }
 342
 343 static inline int
 344 tcf_match_indev(struct sk_buff *skb, char *indev)
 345 {
 346         struct net_device *dev;
 347
 348         if (indev[0]) {
 349                 if  (!skb->skb_iif)
 350                         return 0;
 351                 dev = __dev_get_by_index(dev_net(skb->dev), skb->skb_iif);
 352                 if (!dev || strcmp(indev, dev->name))
 353                         return 0;
 354         }
 355
 356         return 1;
 357 }
 358 #endif /* CONFIG_NET_CLS_IND */
 359
 360 #endif