#ifndef _NET_NF_TABLES_H
#define _NET_NF_TABLES_H
#include <linux/list.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netlink.h>
#define NFT_JUMP_STACK_SIZE 16
struct nft_pktinfo {
struct sk_buff *skb;
const struct net_device *in;
const struct net_device *out;
u8 hooknum;
u8 nhoff;
u8 thoff;
};
struct nft_data {
union {
u32 data[4];
struct {
u32 verdict;
struct nft_chain *chain;
};
};
} __attribute__((aligned(__alignof__(u64))));
static inline int nft_data_cmp(const struct nft_data *d1,
const struct nft_data *d2,
unsigned int len)
{
return memcmp(d1->data, d2->data, len);
}
static inline void nft_data_copy(struct nft_data *dst,
const struct nft_data *src)
{
BUILD_BUG_ON(__alignof__(*dst) != __alignof__(u64));
*(u64 *)&dst->data[0] = *(u64 *)&src->data[0];
*(u64 *)&dst->data[2] = *(u64 *)&src->data[2];
}
static inline void nft_data_debug(const struct nft_data *data)
{
pr_debug("data[0]=%x data[1]=%x data[2]=%x data[3]=%x\n",
data->data[0], data->data[1],
data->data[2], data->data[3]);
}
/**
* struct nft_ctx - nf_tables rule/set context
*
* @skb: netlink skb
* @nlh: netlink message header
* @afi: address family info
* @table: the table the chain is contained in
* @chain: the chain the rule is contained in
*/
struct nft_ctx {
const struct sk_buff *skb;
const struct nlmsghdr *nlh;
const struct nft_af_info *afi;
const struct nft_table *table;
const struct nft_chain *chain;
};
struct nft_data_desc {
enum nft_data_types type;
unsigned int len;
};
extern int nft_data_init(const struct nft_ctx *ctx, struct nft_data *data,
struct nft_data_desc *desc, const struct nlattr *nla);
extern void nft_data_uninit(const struct nft_data *data,
enum nft_data_types type);
extern int nft_data_dump(struct sk_buff *skb, int attr,
const struct nft_data *data,
enum nft_data_types type, unsigned int len);
static inline enum nft_data_types nft_dreg_to_type(enum nft_registers reg)
{
return reg == NFT_REG_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
}
static inline enum nft_registers nft_type_to_reg(enum nft_data_types type)
{
return type == NFT_DATA_VERDICT ? NFT_REG_VERDICT : NFT_REG_1;
}
extern int nft_validate_input_register(enum nft_registers reg);
extern int nft_validate_output_register(enum nft_registers reg);
extern int nft_validate_data_load(const struct nft_ctx *ctx,
enum nft_registers reg,
const struct nft_data *data,
enum nft_data_types type);
/**
* struct nft_set_elem - generic representation of set elements
*
* @cookie: implementation specific element cookie
* @key: element key
* @data: element data (maps only)
* @flags: element flags (end of interval)
*
* The cookie can be used to store a handle to the element for subsequent
* removal.
*/
struct nft_set_elem {
void *cookie;
struct nft_data key;
struct nft_data data;
u32 flags;
};
struct nft_set;
struct nft_set_iter {
unsigned int count;
unsigned int skip;
int err;
int (*fn)(const struct nft_ctx *ctx,
const struct nft_set *set,
const struct nft_set_iter *iter,
const struct nft_set_elem *elem);
};
/**
* struct nft_set_ops - nf_tables set operations
*
* @lookup: look up an element within the set
* @insert: insert new element into set
* @remove: remove element from set
* @walk: iterate over all set elemeennts
* @privsize: function to return size of set private data
* @init: initialize private data of new set instance
* @destroy: destroy private data of set instance
* @list: nf_tables_set_ops list node
* @owner: module reference
* @features: features supported by the implementation
*/
struct nft_set_ops {
bool (*lookup)(const struct nft_set *set,
const struct nft_data *key,
struct nft_data *data);
int (*get)(const struct nft_set *set,
struct nft_set_elem *elem);
int (*insert)(const struct nft_set *set,
const struct nft_set_elem *elem);
void (*remove)(const struct nft_set *set,
const struct nft_set_elem *elem);
void (*walk)(const struct nft_ctx *ctx,
const struct nft_set *set,
struct nft_set_iter *iter);
unsigned int (*privsize)(const struct nlattr * const nla[]);
int (*init)(const struct nft_set *set,
const struct nlattr * const nla[]);
void (*destroy)(const struct nft_set *set);
struct list_head list;
struct module *owner;
u32 features;
};
extern int nft_register_set(struct nft_set_ops *ops);
extern void nft_unregister_set(struct nft_set_ops *ops);
/**
* struct nft_set - nf_tables set instance
*
* @list: table set list node
* @bindings: list of set bindings
* @name: name of the set
* @ktype: key type (numeric type defined by userspace, not used in the kernel)
* @dtype: data type (verdict or numeric type defined by userspace)
* @ops: set ops
* @flags: set flags
* @klen: key length
* @dlen: data length
* @data: private set data
*/
struct nft_set {
struct list_head list;
struct list_head bindings;
char name[IFNAMSIZ];
u32 ktype;
u32 dtype;
/* runtime data below here */
const struct nft_set_ops *ops ____cacheline_aligned;
u16 flags;
u8 klen;
u8 dlen;
unsigned char data[]
__attribute__((aligned(__alignof__(u64))));
};
static inline void *nft_set_priv(const struct nft_set *set)
{
return (void *)set->data;
}
extern struct nft_set *nf_tables_set_lookup(const struct nft_table *table,
const struct nlattr *nla);
/**
* struct nft_set_binding - nf_tables set binding
*
* @list: set bindings list node
* @chain: chain containing the rule bound to the set
*
* A set binding contains all information necessary for validation
* of new elements added to a bound set.
*/
struct nft_set_binding {
struct list_head list;
const struct nft_chain *chain;
};
extern int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
struct nft_set_binding *binding);
extern void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set,
struct nft_set_binding *binding);
/**
* struct nft_expr_ops - nf_tables expression operations
*
* @eval: Expression evaluation function
* @init: initialization function
* @destroy: destruction function
* @dump: function to dump parameters
* @list: used internally
* @name: Identifier
* @owner: module reference
* @policy: netlink attribute policy
* @maxattr: highest netlink attribute number
* @size: full expression size, including private data size
*/
struct nft_expr;
struct nft_expr_ops {
void (*eval)(const struct nft_expr *expr,
struct nft_data data[NFT_REG_MAX + 1],
const struct nft_pktinfo *pkt);
int (*init)(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[]);
void (*destroy)(const struct nft_expr *expr);
int (*dump)(struct sk_buff *skb,
const struct nft_expr *expr);
const struct nft_data * (*get_verdict)(const struct nft_expr *expr);
struct list_head list;
const char *name;
struct module *owner;
const struct nla_policy *policy;
unsigned int maxattr;
unsigned int size;
};
#define NFT_EXPR_SIZE(size) (sizeof(struct nft_expr) + \
ALIGN(size, __alignof__(struct nft_expr)))
/**
* struct nft_expr - nf_tables expression
*
* @ops: expression ops
* @data: expression private data
*/
struct nft_expr {
const struct nft_expr_ops *ops;
unsigned char data[];
};
static inline void *nft_expr_priv(const struct nft_expr *expr)
{
return (void *)expr->data;
}
/**
* struct nft_rule - nf_tables rule
*
* @list: used internally
* @rcu_head: used internally for rcu
* @handle: rule handle
* @dlen: length of expression data
* @data: expression data
*/
struct nft_rule {
struct list_head list;
struct rcu_head rcu_head;
u64 handle:48,
dlen:16;
unsigned char data[]
__attribute__((aligned(__alignof__(struct nft_expr))));
};
static inline struct nft_expr *nft_expr_first(const struct nft_rule *rule)
{
return (struct nft_expr *)&rule->data[0];
}
static inline struct nft_expr *nft_expr_next(const struct nft_expr *expr)
{
return ((void *)expr) + expr->ops->size;
}
static inline struct nft_expr *nft_expr_last(const struct nft_rule *rule)
{
return (struct nft_expr *)&rule->data[rule->dlen];
}
/*
* The last pointer isn't really necessary, but the compiler isn't able to
* determine that the result of nft_expr_last() is always the same since it
* can't assume that the dlen value wasn't changed within calls in the loop.
*/
#define nft_rule_for_each_expr(expr, last, rule) \
for ((expr) = nft_expr_first(rule), (last) = nft_expr_last(rule); \
(expr) != (last); \
(expr) = nft_expr_next(expr))
enum nft_chain_flags {
NFT_BASE_CHAIN = 0x1,
NFT_CHAIN_BUILTIN = 0x2,
};
/**
* struct nft_chain - nf_tables chain
*
* @rules: list of rules in the chain
* @list: used internally
* @rcu_head: used internally
* @handle: chain handle
* @flags: bitmask of enum nft_chain_flags
* @use: number of jump references to this chain
* @level: length of longest path to this chain
* @name: name of the chain
*/
struct nft_chain {
struct list_head rules;
struct list_head list;
struct rcu_head rcu_head;
u64 handle;
u8 flags;
u16 use;
u16 level;
char name[NFT_CHAIN_MAXNAMELEN];
};
/**
* struct nft_base_chain - nf_tables base chain
*
* @ops: netfilter hook ops
* @chain: the chain
*/
struct nft_base_chain {
struct nf_hook_ops ops;
struct nft_chain chain;
};
static inline struct nft_base_chain *nft_base_chain(const struct nft_chain *chain)
{
return container_of(chain, struct nft_base_chain, chain);
}
extern unsigned int nft_do_chain(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *));
enum nft_table_flags {
NFT_TABLE_BUILTIN = 0x1,
};
/**
* struct nft_table - nf_tables table
*
* @list: used internally
* @chains: chains in the table
* @sets: sets in the table
* @hgenerator: handle generator state
* @use: number of chain references to this table
* @flags: table flag (see enum nft_table_flags)
* @name: name of the table
*/
struct nft_table {
struct list_head list;
struct list_head chains;
struct list_head sets;
u64 hgenerator;
u32 use;
u16 flags;
char name[];
};
/**
* struct nft_af_info - nf_tables address family info
*
* @list: used internally
* @family: address family
* @nhooks: number of hooks in this family
* @owner: module owner
* @tables: used internally
* @hooks: hookfn overrides for packet validation
*/
struct nft_af_info {
struct list_head list;
int family;
unsigned int nhooks;
struct module *owner;
struct list_head tables;
nf_hookfn *hooks[NF_MAX_HOOKS];
};
extern int nft_register_afinfo(struct nft_af_info *);
extern void nft_unregister_afinfo(struct nft_af_info *);
extern int nft_register_table(struct nft_table *, int family);
extern void nft_unregister_table(struct nft_table *, int family);
extern int nft_register_expr(struct nft_expr_ops *);
extern void nft_unregister_expr(struct nft_expr_ops *);
#define MODULE_ALIAS_NFT_FAMILY(family) \
MODULE_ALIAS("nft-afinfo-" __stringify(family))
#define MODULE_ALIAS_NFT_TABLE(family, name) \
MODULE_ALIAS("nft-table-" __stringify(family) "-" name)
#define MODULE_ALIAS_NFT_EXPR(name) \
MODULE_ALIAS("nft-expr-" name)
#define MODULE_ALIAS_NFT_SET() \
MODULE_ALIAS("nft-set")
#endif /* _NET_NF_TABLES_H */
