/* SPDX-License-Identifier: GPL-2.0 */
/*
 *  ebtables
 *
 *      Authors:
 *      Bart De Schuymer                <bdschuym@pandora.be>
 *
 *  ebtables.c,v 2.0, April, 2002
 *
 *  This code is strongly inspired by the iptables code which is
 *  Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
 */
#ifndef __LINUX_BRIDGE_EFF_H
#define __LINUX_BRIDGE_EFF_H

#include <linux/if.h>
#include <linux/if_ether.h>
#include <uapi/linux/netfilter_bridge/ebtables.h>

struct ebt_match {
        struct list_head list;
        const char name[EBT_FUNCTION_MAXNAMELEN];
        bool (*match)(const struct sk_buff *skb, const struct net_device *in,
                const struct net_device *out, const struct xt_match *match,
                const void *matchinfo, int offset, unsigned int protoff,
                bool *hotdrop);
        bool (*checkentry)(const char *table, const void *entry,
                const struct xt_match *match, void *matchinfo,
                unsigned int hook_mask);
        void (*destroy)(const struct xt_match *match, void *matchinfo);
        unsigned int matchsize;
        u_int8_t revision;
        u_int8_t family;
        struct module *me;
};

struct ebt_watcher {
        struct list_head list;
        const char name[EBT_FUNCTION_MAXNAMELEN];
        unsigned int (*target)(struct sk_buff *skb,
                const struct net_device *in, const struct net_device *out,
                unsigned int hook_num, const struct xt_target *target,
                const void *targinfo);
        bool (*checkentry)(const char *table, const void *entry,
                const struct xt_target *target, void *targinfo,
                unsigned int hook_mask);
        void (*destroy)(const struct xt_target *target, void *targinfo);
        unsigned int targetsize;
        u_int8_t revision;
        u_int8_t family;
        struct module *me;
};

struct ebt_target {
        struct list_head list;
        const char name[EBT_FUNCTION_MAXNAMELEN];
        /* returns one of the standard EBT_* verdicts */
        unsigned int (*target)(struct sk_buff *skb,
                const struct net_device *in, const struct net_device *out,
                unsigned int hook_num, const struct xt_target *target,
                const void *targinfo);
        bool (*checkentry)(const char *table, const void *entry,
                const struct xt_target *target, void *targinfo,
                unsigned int hook_mask);
        void (*destroy)(const struct xt_target *target, void *targinfo);
        unsigned int targetsize;
        u_int8_t revision;
        u_int8_t family;
        struct module *me;
};

/* used for jumping from and into user defined chains (udc) */
struct ebt_chainstack {
        struct ebt_entries *chaininfo; /* pointer to chain data */
        struct ebt_entry *e; /* pointer to entry data */
        unsigned int n; /* n'th entry */
};

struct ebt_table_info {
        /* total size of the entries */
        unsigned int entries_size;
        unsigned int nentries;
        /* pointers to the start of the chains */
        struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
        /* room to maintain the stack used for jumping from and into udc */
        struct ebt_chainstack **chainstack;
        char *entries;
        struct ebt_counter counters[] ____cacheline_aligned;
};

struct ebt_table {
        struct list_head list;
        char name[EBT_TABLE_MAXNAMELEN];
        struct ebt_replace_kernel *table;
        unsigned int valid_hooks;
        rwlock_t lock;
        /* the data used by the kernel */
        struct ebt_table_info *private;
        struct nf_hook_ops *ops;
        struct module *me;
};

#define EBT_ALIGN(s) (((s) + (__alignof__(struct _xt_align)-1)) & \
                     ~(__alignof__(struct _xt_align)-1))

extern int ebt_register_table(struct net *net,
                              const struct ebt_table *table,
                              const struct nf_hook_ops *ops);
extern void ebt_unregister_table(struct net *net, const char *tablename);
void ebt_unregister_table_pre_exit(struct net *net, const char *tablename);
extern unsigned int ebt_do_table(void *priv, struct sk_buff *skb,
                                 const struct nf_hook_state *state);

/* True if the hook mask denotes that the rule is in a base chain,
 * used in the check() functions */
#define BASE_CHAIN (par->hook_mask & (1 << NF_BR_NUMHOOKS))
/* Clear the bit in the hook mask that tells if the rule is on a base chain */
#define CLEAR_BASE_CHAIN_BIT (par->hook_mask &= ~(1 << NF_BR_NUMHOOKS))

static inline bool ebt_invalid_target(int target)
{
        return (target < -NUM_STANDARD_TARGETS || target >= 0);
}

int ebt_register_template(const struct ebt_table *t, int(*table_init)(struct net *net));
void ebt_unregister_template(const struct ebt_table *t);
#endif