Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * ebtable_filter | |
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 FILTER_VALID_HOOKS ((1 << NF_BR_LOCAL_IN) | (1 << NF_BR_FORWARD) | \ | |
15 | (1 << NF_BR_LOCAL_OUT)) | |
16 | ||
17 | static struct ebt_entries initial_chains[] = | |
18 | { | |
19 | { | |
20 | .name = "INPUT", | |
21 | .policy = EBT_ACCEPT, | |
22 | }, | |
23 | { | |
24 | .name = "FORWARD", | |
25 | .policy = EBT_ACCEPT, | |
26 | }, | |
27 | { | |
28 | .name = "OUTPUT", | |
29 | .policy = EBT_ACCEPT, | |
30 | }, | |
31 | }; | |
32 | ||
33 | static struct ebt_replace initial_table = | |
34 | { | |
35 | .name = "filter", | |
36 | .valid_hooks = FILTER_VALID_HOOKS, | |
37 | .entries_size = 3 * sizeof(struct ebt_entries), | |
38 | .hook_entry = { | |
39 | [NF_BR_LOCAL_IN] = &initial_chains[0], | |
40 | [NF_BR_FORWARD] = &initial_chains[1], | |
41 | [NF_BR_LOCAL_OUT] = &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 & ~FILTER_VALID_HOOKS) | |
49 | return -EINVAL; | |
50 | return 0; | |
51 | } | |
52 | ||
53 | static struct ebt_table frame_filter = | |
54 | { | |
55 | .name = "filter", | |
56 | .table = &initial_table, | |
57 | .valid_hooks = FILTER_VALID_HOOKS, | |
58 | .lock = RW_LOCK_UNLOCKED, | |
59 | .check = check, | |
60 | .me = THIS_MODULE, | |
61 | }; | |
62 | ||
63 | static unsigned int | |
64 | ebt_hook (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_filter); | |
68 | } | |
69 | ||
70 | static struct nf_hook_ops ebt_ops_filter[] = { | |
71 | { | |
72 | .hook = ebt_hook, | |
73 | .owner = THIS_MODULE, | |
74 | .pf = PF_BRIDGE, | |
75 | .hooknum = NF_BR_LOCAL_IN, | |
76 | .priority = NF_BR_PRI_FILTER_BRIDGED, | |
77 | }, | |
78 | { | |
79 | .hook = ebt_hook, | |
80 | .owner = THIS_MODULE, | |
81 | .pf = PF_BRIDGE, | |
82 | .hooknum = NF_BR_FORWARD, | |
83 | .priority = NF_BR_PRI_FILTER_BRIDGED, | |
84 | }, | |
85 | { | |
86 | .hook = ebt_hook, | |
87 | .owner = THIS_MODULE, | |
88 | .pf = PF_BRIDGE, | |
89 | .hooknum = NF_BR_LOCAL_OUT, | |
90 | .priority = NF_BR_PRI_FILTER_OTHER, | |
91 | }, | |
92 | }; | |
93 | ||
94 | static int __init init(void) | |
95 | { | |
96 | int i, j, ret; | |
97 | ||
98 | ret = ebt_register_table(&frame_filter); | |
99 | if (ret < 0) | |
100 | return ret; | |
101 | for (i = 0; i < ARRAY_SIZE(ebt_ops_filter); i++) | |
102 | if ((ret = nf_register_hook(&ebt_ops_filter[i])) < 0) | |
103 | goto cleanup; | |
104 | return ret; | |
105 | cleanup: | |
106 | for (j = 0; j < i; j++) | |
107 | nf_unregister_hook(&ebt_ops_filter[j]); | |
108 | ebt_unregister_table(&frame_filter); | |
109 | return ret; | |
110 | } | |
111 | ||
112 | static void __exit fini(void) | |
113 | { | |
114 | int i; | |
115 | ||
116 | for (i = 0; i < ARRAY_SIZE(ebt_ops_filter); i++) | |
117 | nf_unregister_hook(&ebt_ops_filter[i]); | |
118 | ebt_unregister_table(&frame_filter); | |
119 | } | |
120 | ||
121 | module_init(init); | |
122 | module_exit(fini); | |
123 | MODULE_LICENSE("GPL"); |