#ifndef _NET_NF_TABLES_H
#define _NET_NF_TABLES_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 net_device *in,
                                   const struct net_device *out)
{
        pkt->skb = skb;
        pkt->in = pkt->xt.in = in;
        pkt->out = pkt->xt.out = out;
        pkt->ops = ops;
        pkt->xt.hooknum = ops->hooknum;
        pkt->xt.family = ops->pf;
}

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
 *
 *      @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,
                  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;
}

int nft_validate_input_register(enum nft_registers reg);
int nft_validate_output_register(enum nft_registers reg);
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_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_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[]);
        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;
        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
 *      @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;
        u32                             size;
        u32                             nelems;
        /* 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;
}

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);

/**
 *      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;
};

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);


/**
 *      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
 */
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;
};

/**
 *      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_data data[NFT_REG_MAX + 1],
                                                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_rule - nf_tables rule
 *
 *      @list: used internally
 *      @handle: rule handle
 *      @genmask: generation mask
 *      @dlen: length of expression data
 *      @ulen: length of user data (used for comments)
 *      @data: expression data
 */
struct nft_rule {
        struct list_head                list;
        u64                             handle:42,
                                        genmask:2,
                                        dlen:12,
                                        ulen:8;
        unsigned char                   data[]
                __attribute__((aligned(__alignof__(struct nft_expr))));
};

/**
 *      struct nft_trans - nf_tables object update in transaction
 *
 *      @rcu_head: rcu head to defer release of transaction data
 *      @list: used internally
 *      @msg_type: message type
 *      @ctx: transaction context
 *      @data: internal information related to the transaction
 */
struct nft_trans {
        struct rcu_head                 rcu_head;
        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)

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 void *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
 *      @net: net namespace that this chain belongs to
 *      @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 net                      *net;
        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 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
 *      @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];
        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[];
};

/**
 *      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 *);

/**
 *      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_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")

#endif /* _NET_NF_TABLES_H */