net, netfilter: Remove redundant goto in ebt_ulog_packet
[linux-2.6.git] / net / bridge / netfilter / ebt_dnat.c
1 /*
2  *  ebt_dnat
3  *
4  *      Authors:
5  *      Bart De Schuymer <bdschuym@pandora.be>
6  *
7  *  June, 2002
8  *
9  */
10 #include <linux/module.h>
11 #include <net/sock.h>
12 #include <linux/netfilter.h>
13 #include <linux/netfilter/x_tables.h>
14 #include <linux/netfilter_bridge/ebtables.h>
15 #include <linux/netfilter_bridge/ebt_nat.h>
16
17 static unsigned int
18 ebt_dnat_tg(struct sk_buff *skb, const struct xt_action_param *par)
19 {
20         const struct ebt_nat_info *info = par->targinfo;
21
22         if (!skb_make_writable(skb, 0))
23                 return EBT_DROP;
24
25         memcpy(eth_hdr(skb)->h_dest, info->mac, ETH_ALEN);
26         return info->target;
27 }
28
29 static int ebt_dnat_tg_check(const struct xt_tgchk_param *par)
30 {
31         const struct ebt_nat_info *info = par->targinfo;
32         unsigned int hook_mask;
33
34         if (BASE_CHAIN && info->target == EBT_RETURN)
35                 return -EINVAL;
36
37         hook_mask = par->hook_mask & ~(1 << NF_BR_NUMHOOKS);
38         if ((strcmp(par->table, "nat") != 0 ||
39             (hook_mask & ~((1 << NF_BR_PRE_ROUTING) |
40             (1 << NF_BR_LOCAL_OUT)))) &&
41             (strcmp(par->table, "broute") != 0 ||
42             hook_mask & ~(1 << NF_BR_BROUTING)))
43                 return -EINVAL;
44         if (INVALID_TARGET)
45                 return -EINVAL;
46         return 0;
47 }
48
49 static struct xt_target ebt_dnat_tg_reg __read_mostly = {
50         .name           = "dnat",
51         .revision       = 0,
52         .family         = NFPROTO_BRIDGE,
53         .hooks          = (1 << NF_BR_NUMHOOKS) | (1 << NF_BR_PRE_ROUTING) |
54                           (1 << NF_BR_LOCAL_OUT) | (1 << NF_BR_BROUTING),
55         .target         = ebt_dnat_tg,
56         .checkentry     = ebt_dnat_tg_check,
57         .targetsize     = sizeof(struct ebt_nat_info),
58         .me             = THIS_MODULE,
59 };
60
61 static int __init ebt_dnat_init(void)
62 {
63         return xt_register_target(&ebt_dnat_tg_reg);
64 }
65
66 static void __exit ebt_dnat_fini(void)
67 {
68         xt_unregister_target(&ebt_dnat_tg_reg);
69 }
70
71 module_init(ebt_dnat_init);
72 module_exit(ebt_dnat_fini);
73 MODULE_DESCRIPTION("Ebtables: Destination MAC address translation");
74 MODULE_LICENSE("GPL");