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         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 #endif