Initial import

1 files changed, 1033 insertions, 0 deletions

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
new file mode 100644
index 000000000..e6bcf55dc
--- /dev/null
+++ b/include/net/netfilter/nf_tables.h
@@ -0,0 +1,1033 @@
+#ifndef _NET_NF_TABLES_H
+#define _NET_NF_TABLES_H
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter/nf_tables.h>
+#include <linux/u64_stats_sync.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;
+	const struct nf_hook_ops	*ops;
+	u8				nhoff;
+	u8				thoff;
+	u8				tprot;
+	/* for x_tables compatibility */
+	struct xt_action_param		xt;
+};
+
+static inline void nft_set_pktinfo(struct nft_pktinfo *pkt,
+				   const struct nf_hook_ops *ops,
+				   struct sk_buff *skb,
+				   const struct nf_hook_state *state)
+{
+	pkt->skb = skb;
+	pkt->in = pkt->xt.in = state->in;
+	pkt->out = pkt->xt.out = state->out;
+	pkt->ops = ops;
+	pkt->xt.hooknum = ops->hooknum;
+	pkt->xt.family = ops->pf;
+}
+
+/**
+ * 	struct nft_verdict - nf_tables verdict
+ *
+ * 	@code: nf_tables/netfilter verdict code
+ * 	@chain: destination chain for NFT_JUMP/NFT_GOTO
+ */
+struct nft_verdict {
+	u32				code;
+	struct nft_chain		*chain;
+};
+
+struct nft_data {
+	union {
+		u32			data[4];
+		struct nft_verdict	verdict;
+	};
+} __attribute__((aligned(__alignof__(u64))));
+
+/**
+ *	struct nft_regs - nf_tables register set
+ *
+ *	@data: data registers
+ *	@verdict: verdict register
+ *
+ *	The first four data registers alias to the verdict register.
+ */
+struct nft_regs {
+	union {
+		u32			data[20];
+		struct nft_verdict	verdict;
+	};
+};
+
+static inline void nft_data_copy(u32 *dst, const struct nft_data *src,
+				 unsigned int len)
+{
+	memcpy(dst, src, len);
+}
+
+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
+ *
+ *	@net: net namespace
+ * 	@afi: address family info
+ * 	@table: the table the chain is contained in
+ * 	@chain: the chain the rule is contained in
+ *	@nla: netlink attributes
+ *	@portid: netlink portID of the original message
+ *	@seq: netlink sequence number
+ *	@report: notify via unicast netlink message
+ */
+struct nft_ctx {
+	struct net			*net;
+	struct nft_af_info		*afi;
+	struct nft_table		*table;
+	struct nft_chain		*chain;
+	const struct nlattr * const 	*nla;
+	u32				portid;
+	u32				seq;
+	bool				report;
+};
+
+struct nft_data_desc {
+	enum nft_data_types		type;
+	unsigned int			len;
+};
+
+int nft_data_init(const struct nft_ctx *ctx,
+		  struct nft_data *data, unsigned int size,
+		  struct nft_data_desc *desc, const struct nlattr *nla);
+void nft_data_uninit(const struct nft_data *data, enum nft_data_types type);
+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;
+}
+
+unsigned int nft_parse_register(const struct nlattr *attr);
+int nft_dump_register(struct sk_buff *skb, unsigned int attr, unsigned int reg);
+
+int nft_validate_register_load(enum nft_registers reg, unsigned int len);
+int nft_validate_register_store(const struct nft_ctx *ctx,
+				enum nft_registers reg,
+				const struct nft_data *data,
+				enum nft_data_types type, unsigned int len);
+
+/**
+ *	struct nft_userdata - user defined data associated with an object
+ *
+ *	@len: length of the data
+ *	@data: content
+ *
+ *	The presence of user data is indicated in an object specific fashion,
+ *	so a length of zero can't occur and the value "len" indicates data
+ *	of length len + 1.
+ */
+struct nft_userdata {
+	u8			len;
+	unsigned char		data[0];
+};
+
+/**
+ *	struct nft_set_elem - generic representation of set elements
+ *
+ *	@key: element key
+ *	@priv: element private data and extensions
+ */
+struct nft_set_elem {
+	union {
+		u32		buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
+		struct nft_data	val;
+	} key;
+	void			*priv;
+};
+
+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_desc - description of set elements
+ *
+ *	@klen: key length
+ *	@dlen: data length
+ *	@size: number of set elements
+ */
+struct nft_set_desc {
+	unsigned int		klen;
+	unsigned int		dlen;
+	unsigned int		size;
+};
+
+/**
+ *	enum nft_set_class - performance class
+ *
+ *	@NFT_LOOKUP_O_1: constant, O(1)
+ *	@NFT_LOOKUP_O_LOG_N: logarithmic, O(log N)
+ *	@NFT_LOOKUP_O_N: linear, O(N)
+ */
+enum nft_set_class {
+	NFT_SET_CLASS_O_1,
+	NFT_SET_CLASS_O_LOG_N,
+	NFT_SET_CLASS_O_N,
+};
+
+/**
+ *	struct nft_set_estimate - estimation of memory and performance
+ *				  characteristics
+ *
+ *	@size: required memory
+ *	@class: lookup performance class
+ */
+struct nft_set_estimate {
+	unsigned int		size;
+	enum nft_set_class	class;
+};
+
+struct nft_set_ext;
+struct nft_expr;
+
+/**
+ *	struct nft_set_ops - nf_tables set operations
+ *
+ *	@lookup: look up an element within the set
+ *	@insert: insert new element into set
+ *	@activate: activate new element in the next generation
+ *	@deactivate: deactivate element in the next generation
+ *	@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
+ *	@elemsize: element private size
+ *	@features: features supported by the implementation
+ */
+struct nft_set_ops {
+	bool				(*lookup)(const struct nft_set *set,
+						  const u32 *key,
+						  const struct nft_set_ext **ext);
+	bool				(*update)(struct nft_set *set,
+						  const u32 *key,
+						  void *(*new)(struct nft_set *,
+							       const struct nft_expr *,
+							       struct nft_regs *),
+						  const struct nft_expr *expr,
+						  struct nft_regs *regs,
+						  const struct nft_set_ext **ext);
+
+	int				(*insert)(const struct nft_set *set,
+						  const struct nft_set_elem *elem);
+	void				(*activate)(const struct nft_set *set,
+						    const struct nft_set_elem *elem);
+	void *				(*deactivate)(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[]);
+	bool				(*estimate)(const struct nft_set_desc *desc,
+						    u32 features,
+						    struct nft_set_estimate *est);
+	int				(*init)(const struct nft_set *set,
+						const struct nft_set_desc *desc,
+						const struct nlattr * const nla[]);
+	void				(*destroy)(const struct nft_set *set);
+
+	struct list_head		list;
+	struct module			*owner;
+	unsigned int			elemsize;
+	u32				features;
+};
+
+int nft_register_set(struct nft_set_ops *ops);
+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)
+ * 	@size: maximum set size
+ * 	@nelems: number of elements
+ * 	@ndeact: number of deactivated elements queued for removal
+ * 	@timeout: default timeout value in msecs
+ * 	@gc_int: garbage collection interval in msecs
+ *	@policy: set parameterization (see enum nft_set_policies)
+ * 	@ops: set ops
+ * 	@pnet: network namespace
+ * 	@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;
+	u32				size;
+	atomic_t			nelems;
+	u32				ndeact;
+	u64				timeout;
+	u32				gc_int;
+	u16				policy;
+	/* runtime data below here */
+	const struct nft_set_ops	*ops ____cacheline_aligned;
+	possible_net_t			pnet;
+	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;
+}
+
+static inline struct nft_set *nft_set_container_of(const void *priv)
+{
+	return (void *)priv - offsetof(struct nft_set, data);
+}
+
+struct nft_set *nf_tables_set_lookup(const struct nft_table *table,
+				     const struct nlattr *nla);
+struct nft_set *nf_tables_set_lookup_byid(const struct net *net,
+					  const struct nlattr *nla);
+
+static inline unsigned long nft_set_gc_interval(const struct nft_set *set)
+{
+	return set->gc_int ? msecs_to_jiffies(set->gc_int) : HZ;
+}
+
+/**
+ *	struct nft_set_binding - nf_tables set binding
+ *
+ *	@list: set bindings list node
+ *	@chain: chain containing the rule bound to the set
+ *	@flags: set action flags
+ *
+ *	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;
+	u32				flags;
+};
+
+int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
+		       struct nft_set_binding *binding);
+void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set,
+			  struct nft_set_binding *binding);
+
+/**
+ *	enum nft_set_extensions - set extension type IDs
+ *
+ *	@NFT_SET_EXT_KEY: element key
+ *	@NFT_SET_EXT_DATA: mapping data
+ *	@NFT_SET_EXT_FLAGS: element flags
+ *	@NFT_SET_EXT_TIMEOUT: element timeout
+ *	@NFT_SET_EXT_EXPIRATION: element expiration time
+ *	@NFT_SET_EXT_USERDATA: user data associated with the element
+ *	@NFT_SET_EXT_EXPR: expression assiociated with the element
+ *	@NFT_SET_EXT_NUM: number of extension types
+ */
+enum nft_set_extensions {
+	NFT_SET_EXT_KEY,
+	NFT_SET_EXT_DATA,
+	NFT_SET_EXT_FLAGS,
+	NFT_SET_EXT_TIMEOUT,
+	NFT_SET_EXT_EXPIRATION,
+	NFT_SET_EXT_USERDATA,
+	NFT_SET_EXT_EXPR,
+	NFT_SET_EXT_NUM
+};
+
+/**
+ *	struct nft_set_ext_type - set extension type
+ *
+ * 	@len: fixed part length of the extension
+ * 	@align: alignment requirements of the extension
+ */
+struct nft_set_ext_type {
+	u8	len;
+	u8	align;
+};
+
+extern const struct nft_set_ext_type nft_set_ext_types[];
+
+/**
+ *	struct nft_set_ext_tmpl - set extension template
+ *
+ *	@len: length of extension area
+ *	@offset: offsets of individual extension types
+ */
+struct nft_set_ext_tmpl {
+	u16	len;
+	u8	offset[NFT_SET_EXT_NUM];
+};
+
+/**
+ *	struct nft_set_ext - set extensions
+ *
+ *	@genmask: generation mask
+ *	@offset: offsets of individual extension types
+ *	@data: beginning of extension data
+ */
+struct nft_set_ext {
+	u8	genmask;
+	u8	offset[NFT_SET_EXT_NUM];
+	char	data[0];
+};
+
+static inline void nft_set_ext_prepare(struct nft_set_ext_tmpl *tmpl)
+{
+	memset(tmpl, 0, sizeof(*tmpl));
+	tmpl->len = sizeof(struct nft_set_ext);
+}
+
+static inline void nft_set_ext_add_length(struct nft_set_ext_tmpl *tmpl, u8 id,
+					  unsigned int len)
+{
+	tmpl->len	 = ALIGN(tmpl->len, nft_set_ext_types[id].align);
+	BUG_ON(tmpl->len > U8_MAX);
+	tmpl->offset[id] = tmpl->len;
+	tmpl->len	+= nft_set_ext_types[id].len + len;
+}
+
+static inline void nft_set_ext_add(struct nft_set_ext_tmpl *tmpl, u8 id)
+{
+	nft_set_ext_add_length(tmpl, id, 0);
+}
+
+static inline void nft_set_ext_init(struct nft_set_ext *ext,
+				    const struct nft_set_ext_tmpl *tmpl)
+{
+	memcpy(ext->offset, tmpl->offset, sizeof(ext->offset));
+}
+
+static inline bool __nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
+{
+	return !!ext->offset[id];
+}
+
+static inline bool nft_set_ext_exists(const struct nft_set_ext *ext, u8 id)
+{
+	return ext && __nft_set_ext_exists(ext, id);
+}
+
+static inline void *nft_set_ext(const struct nft_set_ext *ext, u8 id)
+{
+	return (void *)ext + ext->offset[id];
+}
+
+static inline struct nft_data *nft_set_ext_key(const struct nft_set_ext *ext)
+{
+	return nft_set_ext(ext, NFT_SET_EXT_KEY);
+}
+
+static inline struct nft_data *nft_set_ext_data(const struct nft_set_ext *ext)
+{
+	return nft_set_ext(ext, NFT_SET_EXT_DATA);
+}
+
+static inline u8 *nft_set_ext_flags(const struct nft_set_ext *ext)
+{
+	return nft_set_ext(ext, NFT_SET_EXT_FLAGS);
+}
+
+static inline u64 *nft_set_ext_timeout(const struct nft_set_ext *ext)
+{
+	return nft_set_ext(ext, NFT_SET_EXT_TIMEOUT);
+}
+
+static inline unsigned long *nft_set_ext_expiration(const struct nft_set_ext *ext)
+{
+	return nft_set_ext(ext, NFT_SET_EXT_EXPIRATION);
+}
+
+static inline struct nft_userdata *nft_set_ext_userdata(const struct nft_set_ext *ext)
+{
+	return nft_set_ext(ext, NFT_SET_EXT_USERDATA);
+}
+
+static inline struct nft_expr *nft_set_ext_expr(const struct nft_set_ext *ext)
+{
+	return nft_set_ext(ext, NFT_SET_EXT_EXPR);
+}
+
+static inline bool nft_set_elem_expired(const struct nft_set_ext *ext)
+{
+	return nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION) &&
+	       time_is_before_eq_jiffies(*nft_set_ext_expiration(ext));
+}
+
+static inline struct nft_set_ext *nft_set_elem_ext(const struct nft_set *set,
+						   void *elem)
+{
+	return elem + set->ops->elemsize;
+}
+
+void *nft_set_elem_init(const struct nft_set *set,
+			const struct nft_set_ext_tmpl *tmpl,
+			const u32 *key, const u32 *data,
+			u64 timeout, gfp_t gfp);
+void nft_set_elem_destroy(const struct nft_set *set, void *elem);
+
+/**
+ *	struct nft_set_gc_batch_head - nf_tables set garbage collection batch
+ *
+ *	@rcu: rcu head
+ *	@set: set the elements belong to
+ *	@cnt: count of elements
+ */
+struct nft_set_gc_batch_head {
+	struct rcu_head			rcu;
+	const struct nft_set		*set;
+	unsigned int			cnt;
+};
+
+#define NFT_SET_GC_BATCH_SIZE	((PAGE_SIZE -				  \
+				  sizeof(struct nft_set_gc_batch_head)) / \
+				 sizeof(void *))
+
+/**
+ *	struct nft_set_gc_batch - nf_tables set garbage collection batch
+ *
+ * 	@head: GC batch head
+ * 	@elems: garbage collection elements
+ */
+struct nft_set_gc_batch {
+	struct nft_set_gc_batch_head	head;
+	void				*elems[NFT_SET_GC_BATCH_SIZE];
+};
+
+struct nft_set_gc_batch *nft_set_gc_batch_alloc(const struct nft_set *set,
+						gfp_t gfp);
+void nft_set_gc_batch_release(struct rcu_head *rcu);
+
+static inline void nft_set_gc_batch_complete(struct nft_set_gc_batch *gcb)
+{
+	if (gcb != NULL)
+		call_rcu(&gcb->head.rcu, nft_set_gc_batch_release);
+}
+
+static inline struct nft_set_gc_batch *
+nft_set_gc_batch_check(const struct nft_set *set, struct nft_set_gc_batch *gcb,
+		       gfp_t gfp)
+{
+	if (gcb != NULL) {
+		if (gcb->head.cnt + 1 < ARRAY_SIZE(gcb->elems))
+			return gcb;
+		nft_set_gc_batch_complete(gcb);
+	}
+	return nft_set_gc_batch_alloc(set, gfp);
+}
+
+static inline void nft_set_gc_batch_add(struct nft_set_gc_batch *gcb,
+					void *elem)
+{
+	gcb->elems[gcb->head.cnt++] = elem;
+}
+
+/**
+ *	struct nft_expr_type - nf_tables expression type
+ *
+ *	@select_ops: function to select nft_expr_ops
+ *	@ops: default ops, used when no select_ops functions is present
+ *	@list: used internally
+ *	@name: Identifier
+ *	@owner: module reference
+ *	@policy: netlink attribute policy
+ *	@maxattr: highest netlink attribute number
+ *	@family: address family for AF-specific types
+ *	@flags: expression type flags
+ */
+struct nft_expr_type {
+	const struct nft_expr_ops	*(*select_ops)(const struct nft_ctx *,
+						       const struct nlattr * const tb[]);
+	const struct nft_expr_ops	*ops;
+	struct list_head		list;
+	const char			*name;
+	struct module			*owner;
+	const struct nla_policy		*policy;
+	unsigned int			maxattr;
+	u8				family;
+	u8				flags;
+};
+
+#define NFT_EXPR_STATEFUL		0x1
+
+/**
+ *	struct nft_expr_ops - nf_tables expression operations
+ *
+ *	@eval: Expression evaluation function
+ *	@size: full expression size, including private data size
+ *	@init: initialization function
+ *	@destroy: destruction function
+ *	@dump: function to dump parameters
+ *	@type: expression type
+ *	@validate: validate expression, called during loop detection
+ *	@data: extra data to attach to this expression operation
+ */
+struct nft_expr;
+struct nft_expr_ops {
+	void				(*eval)(const struct nft_expr *expr,
+						struct nft_regs *regs,
+						const struct nft_pktinfo *pkt);
+	unsigned int			size;
+
+	int				(*init)(const struct nft_ctx *ctx,
+						const struct nft_expr *expr,
+						const struct nlattr * const tb[]);
+	void				(*destroy)(const struct nft_ctx *ctx,
+						   const struct nft_expr *expr);
+	int				(*dump)(struct sk_buff *skb,
+						const struct nft_expr *expr);
+	int				(*validate)(const struct nft_ctx *ctx,
+						    const struct nft_expr *expr,
+						    const struct nft_data **data);
+	const struct nft_expr_type	*type;
+	void				*data;
+};
+
+#define NFT_EXPR_MAXATTR		16
+#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_expr *nft_expr_init(const struct nft_ctx *ctx,
+			       const struct nlattr *nla);
+void nft_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr);
+int nft_expr_dump(struct sk_buff *skb, unsigned int attr,
+		  const struct nft_expr *expr);
+
+static inline void nft_expr_clone(struct nft_expr *dst, struct nft_expr *src)
+{
+	__module_get(src->ops->type->owner);
+	memcpy(dst, src, src->ops->size);
+}
+
+/**
+ *	struct nft_rule - nf_tables rule
+ *
+ *	@list: used internally
+ *	@handle: rule handle
+ *	@genmask: generation mask
+ *	@dlen: length of expression data
+ *	@udata: user data is appended to the rule
+ *	@data: expression data
+ */
+struct nft_rule {
+	struct list_head		list;
+	u64				handle:42,
+					genmask:2,
+					dlen:12,
+					udata:1;
+	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];
+}
+
+static inline struct nft_userdata *nft_userdata(const struct nft_rule *rule)
+{
+	return (void *)&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_INACTIVE		= 0x2,
+};
+
+/**
+ *	struct nft_chain - nf_tables chain
+ *
+ *	@rules: list of rules in the chain
+ *	@list: used internally
+ *	@table: table that this chain belongs to
+ *	@handle: chain handle
+ *	@use: number of jump references to this chain
+ *	@level: length of longest path to this chain
+ *	@flags: bitmask of enum nft_chain_flags
+ *	@name: name of the chain
+ */
+struct nft_chain {
+	struct list_head		rules;
+	struct list_head		list;
+	struct nft_table		*table;
+	u64				handle;
+	u32				use;
+	u16				level;
+	u8				flags;
+	char				name[NFT_CHAIN_MAXNAMELEN];
+};
+
+enum nft_chain_type {
+	NFT_CHAIN_T_DEFAULT = 0,
+	NFT_CHAIN_T_ROUTE,
+	NFT_CHAIN_T_NAT,
+	NFT_CHAIN_T_MAX
+};
+
+/**
+ * 	struct nf_chain_type - nf_tables chain type info
+ *
+ * 	@name: name of the type
+ * 	@type: numeric identifier
+ * 	@family: address family
+ * 	@owner: module owner
+ * 	@hook_mask: mask of valid hooks
+ * 	@hooks: hookfn overrides
+ */
+struct nf_chain_type {
+	const char			*name;
+	enum nft_chain_type		type;
+	int				family;
+	struct module			*owner;
+	unsigned int			hook_mask;
+	nf_hookfn			*hooks[NF_MAX_HOOKS];
+};
+
+int nft_chain_validate_dependency(const struct nft_chain *chain,
+				  enum nft_chain_type type);
+int nft_chain_validate_hooks(const struct nft_chain *chain,
+                             unsigned int hook_flags);
+
+struct nft_stats {
+	u64			bytes;
+	u64			pkts;
+	struct u64_stats_sync	syncp;
+};
+
+#define NFT_HOOK_OPS_MAX		2
+
+/**
+ *	struct nft_base_chain - nf_tables base chain
+ *
+ *	@ops: netfilter hook ops
+ *	@pnet: net namespace that this chain belongs to
+ *	@type: chain type
+ *	@policy: default policy
+ *	@stats: per-cpu chain stats
+ *	@chain: the chain
+ */
+struct nft_base_chain {
+	struct nf_hook_ops		ops[NFT_HOOK_OPS_MAX];
+	possible_net_t			pnet;
+	const struct nf_chain_type	*type;
+	u8				policy;
+	struct nft_stats __percpu	*stats;
+	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);
+}
+
+unsigned int nft_do_chain(struct nft_pktinfo *pkt,
+			  const struct nf_hook_ops *ops);
+
+/**
+ *	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[NFT_TABLE_MAXNAMELEN];
+};
+
+/**
+ *	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
+ *	@nops: number of hook ops in this family
+ *	@hook_ops_init: initialization function for chain hook ops
+ *	@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;
+	unsigned int			nops;
+	void				(*hook_ops_init)(struct nf_hook_ops *,
+							 unsigned int);
+	nf_hookfn			*hooks[NF_MAX_HOOKS];
+};
+
+int nft_register_afinfo(struct net *, struct nft_af_info *);
+void nft_unregister_afinfo(struct nft_af_info *);
+
+int nft_register_chain_type(const struct nf_chain_type *);
+void nft_unregister_chain_type(const struct nf_chain_type *);
+
+int nft_register_expr(struct nft_expr_type *);
+void nft_unregister_expr(struct nft_expr_type *);
+
+#define nft_dereference(p)					\
+	nfnl_dereference(p, NFNL_SUBSYS_NFTABLES)
+
+#define MODULE_ALIAS_NFT_FAMILY(family)	\
+	MODULE_ALIAS("nft-afinfo-" __stringify(family))
+
+#define MODULE_ALIAS_NFT_CHAIN(family, name) \
+	MODULE_ALIAS("nft-chain-" __stringify(family) "-" name)
+
+#define MODULE_ALIAS_NFT_AF_EXPR(family, name) \
+	MODULE_ALIAS("nft-expr-" __stringify(family) "-" name)
+
+#define MODULE_ALIAS_NFT_EXPR(name) \
+	MODULE_ALIAS("nft-expr-" name)
+
+#define MODULE_ALIAS_NFT_SET() \
+	MODULE_ALIAS("nft-set")
+
+/*
+ * The gencursor defines two generations, the currently active and the
+ * next one. Objects contain a bitmask of 2 bits specifying the generations
+ * they're active in. A set bit means they're inactive in the generation
+ * represented by that bit.
+ *
+ * New objects start out as inactive in the current and active in the
+ * next generation. When committing the ruleset the bitmask is cleared,
+ * meaning they're active in all generations. When removing an object,
+ * it is set inactive in the next generation. After committing the ruleset,
+ * the objects are removed.
+ */
+static inline unsigned int nft_gencursor_next(const struct net *net)
+{
+	return net->nft.gencursor + 1 == 1 ? 1 : 0;
+}
+
+static inline u8 nft_genmask_next(const struct net *net)
+{
+	return 1 << nft_gencursor_next(net);
+}
+
+static inline u8 nft_genmask_cur(const struct net *net)
+{
+	/* Use ACCESS_ONCE() to prevent refetching the value for atomicity */
+	return 1 << ACCESS_ONCE(net->nft.gencursor);
+}
+
+#define NFT_GENMASK_ANY		((1 << 0) | (1 << 1))
+
+/*
+ * Set element transaction helpers
+ */
+
+static inline bool nft_set_elem_active(const struct nft_set_ext *ext,
+				       u8 genmask)
+{
+	return !(ext->genmask & genmask);
+}
+
+static inline void nft_set_elem_change_active(const struct nft_set *set,
+					      struct nft_set_ext *ext)
+{
+	ext->genmask ^= nft_genmask_next(read_pnet(&set->pnet));
+}
+
+/*
+ * We use a free bit in the genmask field to indicate the element
+ * is busy, meaning it is currently being processed either by
+ * the netlink API or GC.
+ *
+ * Even though the genmask is only a single byte wide, this works
+ * because the extension structure if fully constant once initialized,
+ * so there are no non-atomic write accesses unless it is already
+ * marked busy.
+ */
+#define NFT_SET_ELEM_BUSY_MASK	(1 << 2)
+
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+#define NFT_SET_ELEM_BUSY_BIT	2
+#elif defined(__BIG_ENDIAN_BITFIELD)
+#define NFT_SET_ELEM_BUSY_BIT	(BITS_PER_LONG - BITS_PER_BYTE + 2)
+#else
+#error
+#endif
+
+static inline int nft_set_elem_mark_busy(struct nft_set_ext *ext)
+{
+	unsigned long *word = (unsigned long *)ext;
+
+	BUILD_BUG_ON(offsetof(struct nft_set_ext, genmask) != 0);
+	return test_and_set_bit(NFT_SET_ELEM_BUSY_BIT, word);
+}
+
+static inline void nft_set_elem_clear_busy(struct nft_set_ext *ext)
+{
+	unsigned long *word = (unsigned long *)ext;
+
+	clear_bit(NFT_SET_ELEM_BUSY_BIT, word);
+}
+
+/**
+ *	struct nft_trans - nf_tables object update in transaction
+ *
+ *	@list: used internally
+ *	@msg_type: message type
+ *	@ctx: transaction context
+ *	@data: internal information related to the transaction
+ */
+struct nft_trans {
+	struct list_head		list;
+	int				msg_type;
+	struct nft_ctx			ctx;
+	char				data[0];
+};
+
+struct nft_trans_rule {
+	struct nft_rule			*rule;
+};
+
+#define nft_trans_rule(trans)	\
+	(((struct nft_trans_rule *)trans->data)->rule)
+
+struct nft_trans_set {
+	struct nft_set			*set;
+	u32				set_id;
+};
+
+#define nft_trans_set(trans)	\
+	(((struct nft_trans_set *)trans->data)->set)
+#define nft_trans_set_id(trans)	\
+	(((struct nft_trans_set *)trans->data)->set_id)
+
+struct nft_trans_chain {
+	bool				update;
+	char				name[NFT_CHAIN_MAXNAMELEN];
+	struct nft_stats __percpu	*stats;
+	u8				policy;
+};
+
+#define nft_trans_chain_update(trans)	\
+	(((struct nft_trans_chain *)trans->data)->update)
+#define nft_trans_chain_name(trans)	\
+	(((struct nft_trans_chain *)trans->data)->name)
+#define nft_trans_chain_stats(trans)	\
+	(((struct nft_trans_chain *)trans->data)->stats)
+#define nft_trans_chain_policy(trans)	\
+	(((struct nft_trans_chain *)trans->data)->policy)
+
+struct nft_trans_table {
+	bool				update;
+	bool				enable;
+};
+
+#define nft_trans_table_update(trans)	\
+	(((struct nft_trans_table *)trans->data)->update)
+#define nft_trans_table_enable(trans)	\
+	(((struct nft_trans_table *)trans->data)->enable)
+
+struct nft_trans_elem {
+	struct nft_set			*set;
+	struct nft_set_elem		elem;
+};
+
+#define nft_trans_elem_set(trans)	\
+	(((struct nft_trans_elem *)trans->data)->set)
+#define nft_trans_elem(trans)	\
+	(((struct nft_trans_elem *)trans->data)->elem)
+
+#endif /* _NET_NF_TABLES_H */