1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 *  ebtables
4 *
5 *	Authors:
6 *	Bart De Schuymer		<bdschuym@pandora.be>
7 *
8 *  ebtables.c,v 2.0, April, 2002
9 *
10 *  This code is strongly inspired by the iptables code which is
11 *  Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
12 */
13#ifndef __LINUX_BRIDGE_EFF_H
14#define __LINUX_BRIDGE_EFF_H
15
16#include <linux/if.h>
17#include <linux/if_ether.h>
18#include <uapi/linux/netfilter_bridge/ebtables.h>
19
20struct ebt_match {
21	struct list_head list;
22	const char name[EBT_FUNCTION_MAXNAMELEN];
23	bool (*match)(const struct sk_buff *skb, const struct net_device *in,
24		const struct net_device *out, const struct xt_match *match,
25		const void *matchinfo, int offset, unsigned int protoff,
26		bool *hotdrop);
27	bool (*checkentry)(const char *table, const void *entry,
28		const struct xt_match *match, void *matchinfo,
29		unsigned int hook_mask);
30	void (*destroy)(const struct xt_match *match, void *matchinfo);
31	unsigned int matchsize;
32	u_int8_t revision;
33	u_int8_t family;
34	struct module *me;
35};
36
37struct ebt_watcher {
38	struct list_head list;
39	const char name[EBT_FUNCTION_MAXNAMELEN];
40	unsigned int (*target)(struct sk_buff *skb,
41		const struct net_device *in, const struct net_device *out,
42		unsigned int hook_num, const struct xt_target *target,
43		const void *targinfo);
44	bool (*checkentry)(const char *table, const void *entry,
45		const struct xt_target *target, void *targinfo,
46		unsigned int hook_mask);
47	void (*destroy)(const struct xt_target *target, void *targinfo);
48	unsigned int targetsize;
49	u_int8_t revision;
50	u_int8_t family;
51	struct module *me;
52};
53
54struct ebt_target {
55	struct list_head list;
56	const char name[EBT_FUNCTION_MAXNAMELEN];
57	/* returns one of the standard EBT_* verdicts */
58	unsigned int (*target)(struct sk_buff *skb,
59		const struct net_device *in, const struct net_device *out,
60		unsigned int hook_num, const struct xt_target *target,
61		const void *targinfo);
62	bool (*checkentry)(const char *table, const void *entry,
63		const struct xt_target *target, void *targinfo,
64		unsigned int hook_mask);
65	void (*destroy)(const struct xt_target *target, void *targinfo);
66	unsigned int targetsize;
67	u_int8_t revision;
68	u_int8_t family;
69	struct module *me;
70};
71
72/* used for jumping from and into user defined chains (udc) */
73struct ebt_chainstack {
74	struct ebt_entries *chaininfo; /* pointer to chain data */
75	struct ebt_entry *e; /* pointer to entry data */
76	unsigned int n; /* n'th entry */
77};
78
79struct ebt_table_info {
80	/* total size of the entries */
81	unsigned int entries_size;
82	unsigned int nentries;
83	/* pointers to the start of the chains */
84	struct ebt_entries *hook_entry[NF_BR_NUMHOOKS];
85	/* room to maintain the stack used for jumping from and into udc */
86	struct ebt_chainstack **chainstack;
87	char *entries;
88	struct ebt_counter counters[] ____cacheline_aligned;
89};
90
91struct ebt_table {
92	struct list_head list;
93	char name[EBT_TABLE_MAXNAMELEN];
94	struct ebt_replace_kernel *table;
95	unsigned int valid_hooks;
96	rwlock_t lock;
97	/* the data used by the kernel */
98	struct ebt_table_info *private;
99	struct nf_hook_ops *ops;
100	struct module *me;
101};
102
103#define EBT_ALIGN(s) (((s) + (__alignof__(struct _xt_align)-1)) & \
104		     ~(__alignof__(struct _xt_align)-1))
105
106extern int ebt_register_table(struct net *net,
107			      const struct ebt_table *table,
108			      const struct nf_hook_ops *ops);
109extern void ebt_unregister_table(struct net *net, const char *tablename);
110void ebt_unregister_table_pre_exit(struct net *net, const char *tablename);
111extern unsigned int ebt_do_table(void *priv, struct sk_buff *skb,
112				 const struct nf_hook_state *state);
113
114/* True if the hook mask denotes that the rule is in a base chain,
115 * used in the check() functions */
116#define BASE_CHAIN (par->hook_mask & (1 << NF_BR_NUMHOOKS))
117/* Clear the bit in the hook mask that tells if the rule is on a base chain */
118#define CLEAR_BASE_CHAIN_BIT (par->hook_mask &= ~(1 << NF_BR_NUMHOOKS))
119
120static inline bool ebt_invalid_target(int target)
121{
122	return (target < -NUM_STANDARD_TARGETS || target >= 0);
123}
124
125int ebt_register_template(const struct ebt_table *t, int(*table_init)(struct net *net));
126void ebt_unregister_template(const struct ebt_table *t);
127#endif
128