| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * ebtable_nat |
| * |
| * Authors: |
| * Bart De Schuymer <bdschuym@pandora.be> |
| * |
| * April, 2002 |
| * |
| */ |
| |
| #include <linux/netfilter_bridge/ebtables.h> |
| #include <uapi/linux/netfilter_bridge.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_kernel 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 const struct ebt_table frame_nat = { |
| .name = "nat", |
| .table = &initial_table, |
| .valid_hooks = NAT_VALID_HOOKS, |
| .me = THIS_MODULE, |
| }; |
| |
| static const struct nf_hook_ops ebt_ops_nat[] = { |
| { |
| .hook = ebt_do_table, |
| .pf = NFPROTO_BRIDGE, |
| .hooknum = NF_BR_LOCAL_OUT, |
| .priority = NF_BR_PRI_NAT_DST_OTHER, |
| }, |
| { |
| .hook = ebt_do_table, |
| .pf = NFPROTO_BRIDGE, |
| .hooknum = NF_BR_POST_ROUTING, |
| .priority = NF_BR_PRI_NAT_SRC, |
| }, |
| { |
| .hook = ebt_do_table, |
| .pf = NFPROTO_BRIDGE, |
| .hooknum = NF_BR_PRE_ROUTING, |
| .priority = NF_BR_PRI_NAT_DST_BRIDGED, |
| }, |
| }; |
| |
| static int frame_nat_table_init(struct net *net) |
| { |
| return ebt_register_table(net, &frame_nat, ebt_ops_nat); |
| } |
| |
| static void __net_exit frame_nat_net_pre_exit(struct net *net) |
| { |
| ebt_unregister_table_pre_exit(net, "nat"); |
| } |
| |
| static void __net_exit frame_nat_net_exit(struct net *net) |
| { |
| ebt_unregister_table(net, "nat"); |
| } |
| |
| static struct pernet_operations frame_nat_net_ops = { |
| .exit = frame_nat_net_exit, |
| .pre_exit = frame_nat_net_pre_exit, |
| }; |
| |
| static int __init ebtable_nat_init(void) |
| { |
| int ret = ebt_register_template(&frame_nat, frame_nat_table_init); |
| |
| if (ret) |
| return ret; |
| |
| ret = register_pernet_subsys(&frame_nat_net_ops); |
| if (ret) { |
| ebt_unregister_template(&frame_nat); |
| return ret; |
| } |
| |
| return ret; |
| } |
| |
| static void __exit ebtable_nat_fini(void) |
| { |
| unregister_pernet_subsys(&frame_nat_net_ops); |
| ebt_unregister_template(&frame_nat); |
| } |
| |
| module_init(ebtable_nat_init); |
| module_exit(ebtable_nat_fini); |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("ebtables legacy stateless nat table"); |