*
*/
+#include <linux/netfilter.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_nat.h>
#include <linux/module.h>
#include <linux/if_arp.h>
#include <net/arp.h>
-static int ebt_target_snat(struct sk_buff **pskb, unsigned int hooknr,
+static int ebt_target_snat(struct sk_buff *skb, 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;
+ const struct ebt_nat_info *info = data;
- if (skb_shared(*pskb) || skb_cloned(*pskb)) {
- struct sk_buff *nskb;
+ if (!skb_make_writable(skb, 0))
+ return EBT_DROP;
- 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_source, info->mac, ETH_ALEN);
+ memcpy(eth_hdr(skb)->h_source, info->mac, ETH_ALEN);
if (!(info->target & NAT_ARP_BIT) &&
- eth_hdr(*pskb)->h_proto == htons(ETH_P_ARP)) {
- struct arphdr _ah, *ap;
+ eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) {
+ const struct arphdr *ap;
+ struct arphdr _ah;
- ap = skb_header_pointer(*pskb, 0, sizeof(_ah), &_ah);
+ ap = skb_header_pointer(skb, 0, sizeof(_ah), &_ah);
if (ap == NULL)
return EBT_DROP;
if (ap->ar_hln != ETH_ALEN)
goto out;
- if (skb_store_bits(*pskb, sizeof(_ah), info->mac,ETH_ALEN))
+ if (skb_store_bits(skb, sizeof(_ah), info->mac,ETH_ALEN))
return EBT_DROP;
}
out:
static int ebt_target_snat_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;
+ const struct ebt_nat_info *info = data;
int tmp;
if (datalen != EBT_ALIGN(sizeof(struct ebt_nat_info)))
return 0;
}
-static struct ebt_target snat =
-{
+static struct ebt_target snat __read_mostly = {
.name = EBT_SNAT_TARGET,
.target = ebt_target_snat,
.check = ebt_target_snat_check,
module_init(ebt_snat_init);
module_exit(ebt_snat_fini);
+MODULE_DESCRIPTION("Ebtables: Source MAC address translation");
MODULE_LICENSE("GPL");