| /* |
| * ebtable_nat |
| * |
| * Authors: |
| * Bart De Schuymer <bdschuym@pandora.be> |
| * |
| * April, 2002 |
| * |
| */ |
| |
| #include <linux/netfilter_bridge/ebtables.h> |
| #include <linux/module.h> |
| |
| #define NAT_VALID_HOOKS ((1 << NF_BR_PRE_ROUTING) | (1 << NF_BR_LOCAL_OUT) | \ |
| (1 << NF_BR_POST_ROUTING)) |
| |
| static struct ebt_entries initial_chains[] = |
| { |
| { |
| .name = "PREROUTING", |
| .policy = EBT_ACCEPT, |
| }, |
| { |
| .name = "OUTPUT", |
| .policy = EBT_ACCEPT, |
| }, |
| { |
| .name = "POSTROUTING", |
| .policy = EBT_ACCEPT, |
| } |
| }; |
| |
| static struct ebt_replace initial_table = |
| { |
| .name = "nat", |
| .valid_hooks = NAT_VALID_HOOKS, |
| .entries_size = 3 * sizeof(struct ebt_entries), |
| .hook_entry = { |
| [NF_BR_PRE_ROUTING] = &initial_chains[0], |
| [NF_BR_LOCAL_OUT] = &initial_chains[1], |
| [NF_BR_POST_ROUTING] = &initial_chains[2], |
| }, |
| .entries = (char *)initial_chains, |
| }; |
| |
| static int check(const struct ebt_table_info *info, unsigned int valid_hooks) |
| { |
| if (valid_hooks & ~NAT_VALID_HOOKS) |
| return -EINVAL; |
| return 0; |
| } |
| |
| static struct ebt_table frame_nat = |
| { |
| .name = "nat", |
| .table = &initial_table, |
| .valid_hooks = NAT_VALID_HOOKS, |
| .lock = RW_LOCK_UNLOCKED, |
| .check = check, |
| .me = THIS_MODULE, |
| }; |
| |
| static unsigned int |
| ebt_nat_dst(unsigned int hook, struct sk_buff **pskb, const struct net_device *in |
| , const struct net_device *out, int (*okfn)(struct sk_buff *)) |
| { |
| return ebt_do_table(hook, pskb, in, out, &frame_nat); |
| } |
| |
| static unsigned int |
| ebt_nat_src(unsigned int hook, struct sk_buff **pskb, const struct net_device *in |
| , const struct net_device *out, int (*okfn)(struct sk_buff *)) |
| { |
| return ebt_do_table(hook, pskb, in, out, &frame_nat); |
| } |
| |
| static struct nf_hook_ops ebt_ops_nat[] = { |
| { |
| .hook = ebt_nat_dst, |
| .owner = THIS_MODULE, |
| .pf = PF_BRIDGE, |
| .hooknum = NF_BR_LOCAL_OUT, |
| .priority = NF_BR_PRI_NAT_DST_OTHER, |
| }, |
| { |
| .hook = ebt_nat_src, |
| .owner = THIS_MODULE, |
| .pf = PF_BRIDGE, |
| .hooknum = NF_BR_POST_ROUTING, |
| .priority = NF_BR_PRI_NAT_SRC, |
| }, |
| { |
| .hook = ebt_nat_dst, |
| .owner = THIS_MODULE, |
| .pf = PF_BRIDGE, |
| .hooknum = NF_BR_PRE_ROUTING, |
| .priority = NF_BR_PRI_NAT_DST_BRIDGED, |
| }, |
| }; |
| |
| static int __init ebtable_nat_init(void) |
| { |
| int i, ret, j; |
| |
| ret = ebt_register_table(&frame_nat); |
| if (ret < 0) |
| return ret; |
| for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++) |
| if ((ret = nf_register_hook(&ebt_ops_nat[i])) < 0) |
| goto cleanup; |
| return ret; |
| cleanup: |
| for (j = 0; j < i; j++) |
| nf_unregister_hook(&ebt_ops_nat[j]); |
| ebt_unregister_table(&frame_nat); |
| return ret; |
| } |
| |
| static void __exit ebtable_nat_fini(void) |
| { |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE(ebt_ops_nat); i++) |
| nf_unregister_hook(&ebt_ops_nat[i]); |
| ebt_unregister_table(&frame_nat); |
| } |
| |
| module_init(ebtable_nat_init); |
| module_exit(ebtable_nat_fini); |
| MODULE_LICENSE("GPL"); |