Merge branch 'master' of /usr/src/ntfs-2.6/
[linux-2.6] / net / bridge / netfilter / ebtable_nat.c
1 /*
2  *  ebtable_nat
3  *
4  *      Authors:
5  *      Bart De Schuymer <bdschuym@pandora.be>
6  *
7  *  April, 2002
8  *
9  */
10
11 #include <linux/netfilter_bridge/ebtables.h>
12 #include <linux/module.h>
13
14 #define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \
15    (1 << NF_BR_POST_ROUTING))
16
17 static struct ebt_entries initial_chains[] =
18 {
19         {
20                 .name   = "PREROUTING",
21                 .policy = EBT_ACCEPT,
22         },
23         {
24                 .name   = "OUTPUT",
25                 .policy = EBT_ACCEPT,
26         },
27         {
28                 .name   = "POSTROUTING",
29                 .policy = EBT_ACCEPT,
30         }
31 };
32
33 static struct ebt_replace initial_table =
34 {
35         .name           = "nat",
36         .valid_hooks    = NAT_VALID_HOOKS,
37         .entries_size   = 3 * sizeof(struct ebt_entries),
38         .hook_entry     = {
39                 [NF_BR_PRE_ROUTING]     = &initial_chains[0],
40                 [NF_BR_LOCAL_OUT]       = &initial_chains[1],
41                 [NF_BR_POST_ROUTING]    = &initial_chains[2],
42         },
43         .entries        = (char *)initial_chains,
44 };
45
46 static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
47 {
48         if (valid_hooks & ~NAT_VALID_HOOKS)
49                 return -EINVAL;
50         return 0;
51 }
52
53 static struct ebt_table frame_nat =
54 {
55         .name           = "nat",
56         .table          = &initial_table,
57         .valid_hooks    = NAT_VALID_HOOKS,
58         .lock           = RW_LOCK_UNLOCKED,
59         .check          = check,
60         .me             = THIS_MODULE,
61 };
62
63 static unsigned int
64 ebt_nat_dst(unsigned int hook, struct sk_buff **pskb, const struct net_device *in
65    , const struct net_device *out, int (*okfn)(struct sk_buff *))
66 {
67         return ebt_do_table(hook, pskb, in, out, &frame_nat);
68 }
69
70 static unsigned int
71 ebt_nat_src(unsigned int hook, struct sk_buff **pskb, const struct net_device *in
72    , const struct net_device *out, int (*okfn)(struct sk_buff *))
73 {
74         return ebt_do_table(hook, pskb, in, out, &frame_nat);
75 }
76
77 static struct nf_hook_ops ebt_ops_nat[] = {
78         {
79                 .hook           = ebt_nat_dst,
80                 .owner          = THIS_MODULE,
81                 .pf             = PF_BRIDGE,
82                 .hooknum        = NF_BR_LOCAL_OUT,
83                 .priority       = NF_BR_PRI_NAT_DST_OTHER,
84         },
85         {
86                 .hook           = ebt_nat_src,
87                 .owner          = THIS_MODULE,
88                 .pf             = PF_BRIDGE,
89                 .hooknum        = NF_BR_POST_ROUTING,
90                 .priority       = NF_BR_PRI_NAT_SRC,
91         },
92         {
93                 .hook           = ebt_nat_dst,
94                 .owner          = THIS_MODULE,
95                 .pf             = PF_BRIDGE,
96                 .hooknum        = NF_BR_PRE_ROUTING,
97                 .priority       = NF_BR_PRI_NAT_DST_BRIDGED,
98         },
99 };
100
101 static int __init init(void)
102 {
103         int i, ret, j;
104
105         ret = ebt_register_table(&frame_nat);
106         if (ret < 0)
107                 return ret;
108         for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++)
109                 if ((ret = nf_register_hook(&ebt_ops_nat[i])) < 0)
110                         goto cleanup;
111         return ret;
112 cleanup:
113         for (j = 0; j < i; j++)
114                 nf_unregister_hook(&ebt_ops_nat[j]);
115         ebt_unregister_table(&frame_nat);
116         return ret;
117 }
118
119 static void __exit fini(void)
120 {
121         int i;
122
123         for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++)
124                 nf_unregister_hook(&ebt_ops_nat[i]);
125         ebt_unregister_table(&frame_nat);
126 }
127
128 module_init(init);
129 module_exit(fini);
130 MODULE_LICENSE("GPL");