// SPDX-License-Identifier: GPL-2.0-only
/*
 *  ebtable_filter
 *
 *      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 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 const struct nf_hook_ops ebt_ops_filter[] = {
        {
                .hook           = ebt_do_table,
                .pf             = NFPROTO_BRIDGE,
                .hooknum        = NF_BR_LOCAL_IN,
                .priority       = NF_BR_PRI_FILTER_BRIDGED,
        },
        {
                .hook           = ebt_do_table,
                .pf             = NFPROTO_BRIDGE,
                .hooknum        = NF_BR_FORWARD,
                .priority       = NF_BR_PRI_FILTER_BRIDGED,
        },
        {
                .hook           = ebt_do_table,
                .pf             = NFPROTO_BRIDGE,
                .hooknum        = NF_BR_LOCAL_OUT,
                .priority       = NF_BR_PRI_FILTER_OTHER,
        },
};

static int frame_filter_table_init(struct net *net)
{
        return ebt_register_table(net, &frame_filter, ebt_ops_filter);
}

static void __net_exit frame_filter_net_pre_exit(struct net *net)
{
        ebt_unregister_table_pre_exit(net, "filter");
}

static void __net_exit frame_filter_net_exit(struct net *net)
{
        ebt_unregister_table(net, "filter");
}

static struct pernet_operations frame_filter_net_ops = {
        .exit = frame_filter_net_exit,
        .pre_exit = frame_filter_net_pre_exit,
};

static int __init ebtable_filter_init(void)
{
        int ret = ebt_register_template(&frame_filter, frame_filter_table_init);

        if (ret)
                return ret;

        ret = register_pernet_subsys(&frame_filter_net_ops);
        if (ret) {
                ebt_unregister_template(&frame_filter);
                return ret;
        }

        return 0;
}

static void __exit ebtable_filter_fini(void)
{
        unregister_pernet_subsys(&frame_filter_net_ops);
        ebt_unregister_template(&frame_filter);
}

module_init(ebtable_filter_init);
module_exit(ebtable_filter_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ebtables legacy filter table");