| /* |
| * ebt_dnat |
| * |
| * Authors: |
| * Bart De Schuymer <bdschuym@pandora.be> |
| * |
| * June, 2002 |
| * |
| */ |
| |
| #include <linux/netfilter_bridge/ebtables.h> |
| #include <linux/netfilter_bridge/ebt_nat.h> |
| #include <linux/module.h> |
| #include <net/sock.h> |
| |
| static int ebt_target_dnat(struct sk_buff **pskb, unsigned int hooknr, |
| const struct net_device *in, const struct net_device *out, |
| const void *data, unsigned int datalen) |
| { |
| struct ebt_nat_info *info = (struct ebt_nat_info *)data; |
| |
| if (skb_shared(*pskb) || skb_cloned(*pskb)) { |
| struct sk_buff *nskb; |
| |
| nskb = skb_copy(*pskb, GFP_ATOMIC); |
| if (!nskb) |
| return NF_DROP; |
| if ((*pskb)->sk) |
| skb_set_owner_w(nskb, (*pskb)->sk); |
| kfree_skb(*pskb); |
| *pskb = nskb; |
| } |
| memcpy(eth_hdr(*pskb)->h_dest, info->mac, ETH_ALEN); |
| return info->target; |
| } |
| |
| static int ebt_target_dnat_check(const char *tablename, unsigned int hookmask, |
| const struct ebt_entry *e, void *data, unsigned int datalen) |
| { |
| struct ebt_nat_info *info = (struct ebt_nat_info *)data; |
| |
| if (BASE_CHAIN && info->target == EBT_RETURN) |
| return -EINVAL; |
| CLEAR_BASE_CHAIN_BIT; |
| if ( (strcmp(tablename, "nat") || |
| (hookmask & ~((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT)))) && |
| (strcmp(tablename, "broute") || hookmask & ~(1 << NF_BR_BROUTING)) ) |
| return -EINVAL; |
| if (datalen != EBT_ALIGN(sizeof(struct ebt_nat_info))) |
| return -EINVAL; |
| if (INVALID_TARGET) |
| return -EINVAL; |
| return 0; |
| } |
| |
| static struct ebt_target dnat = |
| { |
| .name = EBT_DNAT_TARGET, |
| .target = ebt_target_dnat, |
| .check = ebt_target_dnat_check, |
| .me = THIS_MODULE, |
| }; |
| |
| static int __init ebt_dnat_init(void) |
| { |
| return ebt_register_target(&dnat); |
| } |
| |
| static void __exit ebt_dnat_fini(void) |
| { |
| ebt_unregister_target(&dnat); |
| } |
| |
| module_init(ebt_dnat_init); |
| module_exit(ebt_dnat_fini); |
| MODULE_LICENSE("GPL"); |