1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Format of an ARP firewall descriptor
4 *
5 * src, tgt, src_mask, tgt_mask, arpop, arpop_mask are always stored in
6 * network byte order.
7 * flags are stored in host byte order (of course).
8 */
9 #ifndef _ARPTABLES_H
10 #define _ARPTABLES_H
11
12 #include <linux/if.h>
13 #include <linux/in.h>
14 #include <linux/if_arp.h>
15 #include <linux/skbuff.h>
16 #include <uapi/linux/netfilter_arp/arp_tables.h>
17
18 /* Standard entry. */
19 struct arpt_standard {
20 struct arpt_entry entry;
21 struct xt_standard_target target;
22 };
23
24 struct arpt_error {
25 struct arpt_entry entry;
26 struct xt_error_target target;
27 };
28
29 #define ARPT_ENTRY_INIT(__size) \
30 { \
31 .target_offset = sizeof(struct arpt_entry), \
32 .next_offset = (__size), \
33 }
34
35 #define ARPT_STANDARD_INIT(__verdict) \
36 { \
37 .entry = ARPT_ENTRY_INIT(sizeof(struct arpt_standard)), \
38 .target = XT_TARGET_INIT(XT_STANDARD_TARGET, \
39 sizeof(struct xt_standard_target)), \
40 .target.verdict = -(__verdict) - 1, \
41 }
42
43 #define ARPT_ERROR_INIT \
44 { \
45 .entry = ARPT_ENTRY_INIT(sizeof(struct arpt_error)), \
46 .target = XT_TARGET_INIT(XT_ERROR_TARGET, \
47 sizeof(struct xt_error_target)), \
48 .target.errorname = "ERROR", \
49 }
50
51 extern void *arpt_alloc_initial_table(const struct xt_table *);
52 int arpt_register_table(struct net *net, const struct xt_table *table,
53 const struct arpt_replace *repl,
54 const struct nf_hook_ops *ops, struct xt_table **res);
55 void arpt_unregister_table(struct net *net, struct xt_table *table,
56 const struct nf_hook_ops *ops);
57 extern unsigned int arpt_do_table(struct sk_buff *skb,
58 const struct nf_hook_state *state,
59 struct xt_table *table);
60
61 #ifdef CONFIG_COMPAT
62 #include <net/compat.h>
63
64 struct compat_arpt_entry {
65 struct arpt_arp arp;
66 __u16 target_offset;
67 __u16 next_offset;
68 compat_uint_t comefrom;
69 struct compat_xt_counters counters;
70 unsigned char elems[0];
71 };
72
73 static inline struct xt_entry_target *
compat_arpt_get_target(struct compat_arpt_entry * e)74 compat_arpt_get_target(struct compat_arpt_entry *e)
75 {
76 return (void *)e + e->target_offset;
77 }
78
79 #endif /* CONFIG_COMPAT */
80 #endif /* _ARPTABLES_H */
81