2 * Filtering ARP tables module.
4 * Copyright (C) 2002 David S. Miller (davem@redhat.com)
8 #include <linux/module.h>
9 #include <linux/netfilter_arp/arp_tables.h>
11 MODULE_LICENSE("GPL");
12 MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
13 MODULE_DESCRIPTION("arptables filter table");
15 #define FILTER_VALID_HOOKS ((1 << NF_ARP_IN) | (1 << NF_ARP_OUT) | \
16 (1 << NF_ARP_FORWARD))
20 struct arpt_replace repl
;
21 struct arpt_standard entries
[3];
22 struct arpt_error term
;
23 } initial_table __net_initdata
= {
26 .valid_hooks
= FILTER_VALID_HOOKS
,
28 .size
= sizeof(struct arpt_standard
) * 3 + sizeof(struct arpt_error
),
31 [NF_ARP_OUT
] = sizeof(struct arpt_standard
),
32 [NF_ARP_FORWARD
] = 2 * sizeof(struct arpt_standard
),
36 [NF_ARP_OUT
] = sizeof(struct arpt_standard
),
37 [NF_ARP_FORWARD
] = 2 * sizeof(struct arpt_standard
),
41 ARPT_STANDARD_INIT(NF_ACCEPT
), /* ARP_IN */
42 ARPT_STANDARD_INIT(NF_ACCEPT
), /* ARP_OUT */
43 ARPT_STANDARD_INIT(NF_ACCEPT
), /* ARP_FORWARD */
45 .term
= ARPT_ERROR_INIT
,
48 static struct xt_table packet_filter
= {
50 .valid_hooks
= FILTER_VALID_HOOKS
,
51 .lock
= __RW_LOCK_UNLOCKED(packet_filter
.lock
),
57 /* The work comes in here from netfilter.c */
58 static unsigned int arpt_in_hook(unsigned int hook
,
60 const struct net_device
*in
,
61 const struct net_device
*out
,
62 int (*okfn
)(struct sk_buff
*))
64 return arpt_do_table(skb
, hook
, in
, out
,
65 dev_net(in
)->ipv4
.arptable_filter
);
68 static unsigned int arpt_out_hook(unsigned int hook
,
70 const struct net_device
*in
,
71 const struct net_device
*out
,
72 int (*okfn
)(struct sk_buff
*))
74 return arpt_do_table(skb
, hook
, in
, out
,
75 dev_net(out
)->ipv4
.arptable_filter
);
78 static unsigned int arpt_forward_hook(unsigned int hook
,
80 const struct net_device
*in
,
81 const struct net_device
*out
,
82 int (*okfn
)(struct sk_buff
*))
84 return arpt_do_table(skb
, hook
, in
, out
,
85 dev_net(in
)->ipv4
.arptable_filter
);
88 static struct nf_hook_ops arpt_ops
[] __read_mostly
= {
94 .priority
= NF_IP_PRI_FILTER
,
97 .hook
= arpt_out_hook
,
100 .hooknum
= NF_ARP_OUT
,
101 .priority
= NF_IP_PRI_FILTER
,
104 .hook
= arpt_forward_hook
,
105 .owner
= THIS_MODULE
,
107 .hooknum
= NF_ARP_FORWARD
,
108 .priority
= NF_IP_PRI_FILTER
,
112 static int __net_init
arptable_filter_net_init(struct net
*net
)
115 net
->ipv4
.arptable_filter
=
116 arpt_register_table(net
, &packet_filter
, &initial_table
.repl
);
117 if (IS_ERR(net
->ipv4
.arptable_filter
))
118 return PTR_ERR(net
->ipv4
.arptable_filter
);
122 static void __net_exit
arptable_filter_net_exit(struct net
*net
)
124 arpt_unregister_table(net
->ipv4
.arptable_filter
);
127 static struct pernet_operations arptable_filter_net_ops
= {
128 .init
= arptable_filter_net_init
,
129 .exit
= arptable_filter_net_exit
,
132 static int __init
arptable_filter_init(void)
136 ret
= register_pernet_subsys(&arptable_filter_net_ops
);
140 ret
= nf_register_hooks(arpt_ops
, ARRAY_SIZE(arpt_ops
));
146 unregister_pernet_subsys(&arptable_filter_net_ops
);
150 static void __exit
arptable_filter_fini(void)
152 nf_unregister_hooks(arpt_ops
, ARRAY_SIZE(arpt_ops
));
153 unregister_pernet_subsys(&arptable_filter_net_ops
);
156 module_init(arptable_filter_init
);
157 module_exit(arptable_filter_fini
);