// SPDX-License-Identifier: GPL-2.0-only /* * ebtable_filter * * Authors: * Bart De Schuymer * * April, 2002 * */ #include #include #include #define FILTER_VALID_HOOKS ((1 << NF_BR_LOCAL_IN) | (1 << NF_BR_FORWARD) | \ (1 << NF_BR_LOCAL_OUT)) static struct ebt_entries initial_chains[] = { { .name = "INPUT", .policy = EBT_ACCEPT, }, { .name = "FORWARD", .policy = EBT_ACCEPT, }, { .name = "OUTPUT", .policy = EBT_ACCEPT, }, }; static struct ebt_replace_kernel initial_table = { .name = "filter", .valid_hooks = FILTER_VALID_HOOKS, .entries_size = 3 * sizeof(struct ebt_entries), .hook_entry = { [NF_BR_LOCAL_IN] = &initial_chains[0], [NF_BR_FORWARD] = &initial_chains[1], [NF_BR_LOCAL_OUT] = &initial_chains[2], }, .entries = (char *)initial_chains, }; static const struct ebt_table frame_filter = { .name = "filter", .table = &initial_table, .valid_hooks = FILTER_VALID_HOOKS, .me = THIS_MODULE, }; static unsigned int ebt_in_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) { return ebt_do_table(skb, state, state->net->xt.frame_filter); } static unsigned int ebt_out_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) { return ebt_do_table(skb, state, state->net->xt.frame_filter); } static const struct nf_hook_ops ebt_ops_filter[] = { { .hook = ebt_in_hook, .pf = NFPROTO_BRIDGE, .hooknum = NF_BR_LOCAL_IN, .priority = NF_BR_PRI_FILTER_BRIDGED, }, { .hook = ebt_in_hook, .pf = NFPROTO_BRIDGE, .hooknum = NF_BR_FORWARD, .priority = NF_BR_PRI_FILTER_BRIDGED, }, { .hook = ebt_out_hook, .pf = NFPROTO_BRIDGE, .hooknum = NF_BR_LOCAL_OUT, .priority = NF_BR_PRI_FILTER_OTHER, }, }; static int __net_init frame_filter_net_init(struct net *net) { return ebt_register_table(net, &frame_filter, ebt_ops_filter, &net->xt.frame_filter); } static void __net_exit frame_filter_net_pre_exit(struct net *net) { ebt_unregister_table_pre_exit(net, "filter", ebt_ops_filter); } static void __net_exit frame_filter_net_exit(struct net *net) { ebt_unregister_table(net, net->xt.frame_filter); } static struct pernet_operations frame_filter_net_ops = { .init = frame_filter_net_init, .exit = frame_filter_net_exit, .pre_exit = frame_filter_net_pre_exit, }; static int __init ebtable_filter_init(void) { return register_pernet_subsys(&frame_filter_net_ops); } static void __exit ebtable_filter_fini(void) { unregister_pernet_subsys(&frame_filter_net_ops); } module_init(ebtable_filter_init); module_exit(ebtable_filter_fini); MODULE_LICENSE("GPL");