| /* |
| * ebtable_nat |
| * |
| * Authors: |
| * Bart De Schuymer <bart.de.schuymer@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[] = |
| { |
| {0, "PREROUTING", 0, EBT_ACCEPT, 0}, |
| {0, "OUTPUT", 0, EBT_ACCEPT, 0}, |
| {0, "POSTROUTING", 0, EBT_ACCEPT, 0} |
| }; |
| |
| static struct ebt_replace initial_table = |
| { |
| "nat", NAT_VALID_HOOKS, 0, 3 * sizeof(struct ebt_entries), |
| { [NF_BR_PRE_ROUTING]&initial_chains[0], [NF_BR_LOCAL_OUT]&initial_chains[1], |
| [NF_BR_POST_ROUTING]&initial_chains[2] }, 0, NULL, (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 = |
| { |
| {NULL, NULL}, "nat", &initial_table, NAT_VALID_HOOKS, |
| RW_LOCK_UNLOCKED, check, NULL |
| }; |
| |
| 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[] = { |
| { { NULL, NULL }, ebt_nat_dst, PF_BRIDGE, NF_BR_LOCAL_OUT, |
| NF_BR_PRI_NAT_DST_OTHER}, |
| { { NULL, NULL }, ebt_nat_src, PF_BRIDGE, NF_BR_POST_ROUTING, |
| NF_BR_PRI_NAT_SRC}, |
| { { NULL, NULL }, ebt_nat_dst, PF_BRIDGE, NF_BR_PRE_ROUTING, |
| NF_BR_PRI_NAT_DST_BRIDGED}, |
| }; |
| |
| static int __init init(void) |
| { |
| int i, ret, j; |
| |
| ret = ebt_register_table(&frame_nat); |
| if (ret < 0) |
| return ret; |
| for (i = 0; i < sizeof(ebt_ops_nat) / sizeof(ebt_ops_nat[0]); 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 fini(void) |
| { |
| int i; |
| |
| for (i = 0; i < sizeof(ebt_ops_nat) / sizeof(ebt_ops_nat[0]); i++) |
| nf_unregister_hook(&ebt_ops_nat[i]); |
| ebt_unregister_table(&frame_nat); |
| } |
| |
| module_init(init); |
| module_exit(fini); |
| EXPORT_NO_SYMBOLS; |
| MODULE_LICENSE("GPL"); |