kernel-fxtec-pro1x/include/net/pkt_cls.h
David S. Miller da521b2c4f net: Fix range checks in tcf_valid_offset().
This function has three bugs:

1) The offset should be valid most of the time, this is just
   a sanity check, therefore we should use "likely" not "unlikely"

2) This is the only place where we can check for arithmetic overflow
   of the pointer plus the length.

3) The existing range checks are off by one, the valid range is
   skb->head to skb_tail_pointer(), inclusive.

Based almost entirely upon a patch by Ralph Loader.

Reported-by: Ralph Loader <suckfish@ihug.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-21 12:43:16 -08:00

359 lines
9.1 KiB
C

#ifndef __NET_PKT_CLS_H
#define __NET_PKT_CLS_H
#include <linux/pkt_cls.h>
#include <net/sch_generic.h>
#include <net/act_api.h>
/* Basic packet classifier frontend definitions. */
struct tcf_walker {
int stop;
int skip;
int count;
int (*fn)(struct tcf_proto *, unsigned long node, struct tcf_walker *);
};
extern int register_tcf_proto_ops(struct tcf_proto_ops *ops);
extern int unregister_tcf_proto_ops(struct tcf_proto_ops *ops);
static inline unsigned long
__cls_set_class(unsigned long *clp, unsigned long cl)
{
unsigned long old_cl;
old_cl = *clp;
*clp = cl;
return old_cl;
}
static inline unsigned long
cls_set_class(struct tcf_proto *tp, unsigned long *clp,
unsigned long cl)
{
unsigned long old_cl;
tcf_tree_lock(tp);
old_cl = __cls_set_class(clp, cl);
tcf_tree_unlock(tp);
return old_cl;
}
static inline void
tcf_bind_filter(struct tcf_proto *tp, struct tcf_result *r, unsigned long base)
{
unsigned long cl;
cl = tp->q->ops->cl_ops->bind_tcf(tp->q, base, r->classid);
cl = cls_set_class(tp, &r->class, cl);
if (cl)
tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
}
static inline void
tcf_unbind_filter(struct tcf_proto *tp, struct tcf_result *r)
{
unsigned long cl;
if ((cl = __cls_set_class(&r->class, 0)) != 0)
tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
}
struct tcf_exts {
#ifdef CONFIG_NET_CLS_ACT
struct tc_action *action;
#endif
};
/* Map to export classifier specific extension TLV types to the
* generic extensions API. Unsupported extensions must be set to 0.
*/
struct tcf_ext_map {
int action;
int police;
};
/**
* tcf_exts_is_predicative - check if a predicative extension is present
* @exts: tc filter extensions handle
*
* Returns 1 if a predicative extension is present, i.e. an extension which
* might cause further actions and thus overrule the regular tcf_result.
*/
static inline int
tcf_exts_is_predicative(struct tcf_exts *exts)
{
#ifdef CONFIG_NET_CLS_ACT
return !!exts->action;
#else
return 0;
#endif
}
/**
* tcf_exts_is_available - check if at least one extension is present
* @exts: tc filter extensions handle
*
* Returns 1 if at least one extension is present.
*/
static inline int
tcf_exts_is_available(struct tcf_exts *exts)
{
/* All non-predicative extensions must be added here. */
return tcf_exts_is_predicative(exts);
}
/**
* tcf_exts_exec - execute tc filter extensions
* @skb: socket buffer
* @exts: tc filter extensions handle
* @res: desired result
*
* Executes all configured extensions. Returns 0 on a normal execution,
* a negative number if the filter must be considered unmatched or
* a positive action code (TC_ACT_*) which must be returned to the
* underlying layer.
*/
static inline int
tcf_exts_exec(struct sk_buff *skb, struct tcf_exts *exts,
struct tcf_result *res)
{
#ifdef CONFIG_NET_CLS_ACT
if (exts->action)
return tcf_action_exec(skb, exts->action, res);
#endif
return 0;
}
extern int tcf_exts_validate(struct tcf_proto *tp, struct nlattr **tb,
struct nlattr *rate_tlv, struct tcf_exts *exts,
const struct tcf_ext_map *map);
extern void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts);
extern void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
struct tcf_exts *src);
extern int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
const struct tcf_ext_map *map);
extern int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
const struct tcf_ext_map *map);
/**
* struct tcf_pkt_info - packet information
*/
struct tcf_pkt_info {
unsigned char * ptr;
int nexthdr;
};
#ifdef CONFIG_NET_EMATCH
struct tcf_ematch_ops;
/**
* struct tcf_ematch - extended match (ematch)
*
* @matchid: identifier to allow userspace to reidentify a match
* @flags: flags specifying attributes and the relation to other matches
* @ops: the operations lookup table of the corresponding ematch module
* @datalen: length of the ematch specific configuration data
* @data: ematch specific data
*/
struct tcf_ematch {
struct tcf_ematch_ops * ops;
unsigned long data;
unsigned int datalen;
u16 matchid;
u16 flags;
};
static inline int tcf_em_is_container(struct tcf_ematch *em)
{
return !em->ops;
}
static inline int tcf_em_is_simple(struct tcf_ematch *em)
{
return em->flags & TCF_EM_SIMPLE;
}
static inline int tcf_em_is_inverted(struct tcf_ematch *em)
{
return em->flags & TCF_EM_INVERT;
}
static inline int tcf_em_last_match(struct tcf_ematch *em)
{
return (em->flags & TCF_EM_REL_MASK) == TCF_EM_REL_END;
}
static inline int tcf_em_early_end(struct tcf_ematch *em, int result)
{
if (tcf_em_last_match(em))
return 1;
if (result == 0 && em->flags & TCF_EM_REL_AND)
return 1;
if (result != 0 && em->flags & TCF_EM_REL_OR)
return 1;
return 0;
}
/**
* struct tcf_ematch_tree - ematch tree handle
*
* @hdr: ematch tree header supplied by userspace
* @matches: array of ematches
*/
struct tcf_ematch_tree {
struct tcf_ematch_tree_hdr hdr;
struct tcf_ematch * matches;
};
/**
* struct tcf_ematch_ops - ematch module operations
*
* @kind: identifier (kind) of this ematch module
* @datalen: length of expected configuration data (optional)
* @change: called during validation (optional)
* @match: called during ematch tree evaluation, must return 1/0
* @destroy: called during destroyage (optional)
* @dump: called during dumping process (optional)
* @owner: owner, must be set to THIS_MODULE
* @link: link to previous/next ematch module (internal use)
*/
struct tcf_ematch_ops {
int kind;
int datalen;
int (*change)(struct tcf_proto *, void *,
int, struct tcf_ematch *);
int (*match)(struct sk_buff *, struct tcf_ematch *,
struct tcf_pkt_info *);
void (*destroy)(struct tcf_proto *,
struct tcf_ematch *);
int (*dump)(struct sk_buff *, struct tcf_ematch *);
struct module *owner;
struct list_head link;
};
extern int tcf_em_register(struct tcf_ematch_ops *);
extern void tcf_em_unregister(struct tcf_ematch_ops *);
extern int tcf_em_tree_validate(struct tcf_proto *, struct nlattr *,
struct tcf_ematch_tree *);
extern void tcf_em_tree_destroy(struct tcf_proto *, struct tcf_ematch_tree *);
extern int tcf_em_tree_dump(struct sk_buff *, struct tcf_ematch_tree *, int);
extern int __tcf_em_tree_match(struct sk_buff *, struct tcf_ematch_tree *,
struct tcf_pkt_info *);
/**
* tcf_em_tree_change - replace ematch tree of a running classifier
*
* @tp: classifier kind handle
* @dst: destination ematch tree variable
* @src: source ematch tree (temporary tree from tcf_em_tree_validate)
*
* This functions replaces the ematch tree in @dst with the ematch
* tree in @src. The classifier in charge of the ematch tree may be
* running.
*/
static inline void tcf_em_tree_change(struct tcf_proto *tp,
struct tcf_ematch_tree *dst,
struct tcf_ematch_tree *src)
{
tcf_tree_lock(tp);
memcpy(dst, src, sizeof(*dst));
tcf_tree_unlock(tp);
}
/**
* tcf_em_tree_match - evaulate an ematch tree
*
* @skb: socket buffer of the packet in question
* @tree: ematch tree to be used for evaluation
* @info: packet information examined by classifier
*
* This function matches @skb against the ematch tree in @tree by going
* through all ematches respecting their logic relations returning
* as soon as the result is obvious.
*
* Returns 1 if the ematch tree as-one matches, no ematches are configured
* or ematch is not enabled in the kernel, otherwise 0 is returned.
*/
static inline int tcf_em_tree_match(struct sk_buff *skb,
struct tcf_ematch_tree *tree,
struct tcf_pkt_info *info)
{
if (tree->hdr.nmatches)
return __tcf_em_tree_match(skb, tree, info);
else
return 1;
}
#define MODULE_ALIAS_TCF_EMATCH(kind) MODULE_ALIAS("ematch-kind-" __stringify(kind))
#else /* CONFIG_NET_EMATCH */
struct tcf_ematch_tree {
};
#define tcf_em_tree_validate(tp, tb, t) ((void)(t), 0)
#define tcf_em_tree_destroy(tp, t) do { (void)(t); } while(0)
#define tcf_em_tree_dump(skb, t, tlv) (0)
#define tcf_em_tree_change(tp, dst, src) do { } while(0)
#define tcf_em_tree_match(skb, t, info) ((void)(info), 1)
#endif /* CONFIG_NET_EMATCH */
static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
{
switch (layer) {
case TCF_LAYER_LINK:
return skb->data;
case TCF_LAYER_NETWORK:
return skb_network_header(skb);
case TCF_LAYER_TRANSPORT:
return skb_transport_header(skb);
}
return NULL;
}
static inline int tcf_valid_offset(const struct sk_buff *skb,
const unsigned char *ptr, const int len)
{
return likely((ptr + len) <= skb_tail_pointer(skb) &&
ptr >= skb->head &&
(ptr <= (ptr + len)));
}
#ifdef CONFIG_NET_CLS_IND
#include <net/net_namespace.h>
static inline int
tcf_change_indev(struct tcf_proto *tp, char *indev, struct nlattr *indev_tlv)
{
if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ)
return -EINVAL;
return 0;
}
static inline int
tcf_match_indev(struct sk_buff *skb, char *indev)
{
struct net_device *dev;
if (indev[0]) {
if (!skb->skb_iif)
return 0;
dev = __dev_get_by_index(dev_net(skb->dev), skb->skb_iif);
if (!dev || strcmp(indev, dev->name))
return 0;
}
return 1;
}
#endif /* CONFIG_NET_CLS_IND */
#endif