// SPDX-License-Identifier: GPL-2.0-only
/*
 *      xt_mark - Netfilter module to match NFMARK value
 *
 *      (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
 *      Copyright © CC Computer Consultants GmbH, 2007 - 2008
 *      Jan Engelhardt <jengelh@medozas.de>
 */

#include <linux/module.h>
#include <linux/skbuff.h>

#include <linux/netfilter/xt_mark.h>
#include <linux/netfilter/x_tables.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
MODULE_DESCRIPTION("Xtables: packet mark operations");
MODULE_ALIAS("ipt_mark");
MODULE_ALIAS("ip6t_mark");
MODULE_ALIAS("ipt_MARK");
MODULE_ALIAS("ip6t_MARK");
MODULE_ALIAS("arpt_MARK");

static unsigned int
mark_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
        const struct xt_mark_tginfo2 *info = par->targinfo;

        skb->mark = (skb->mark & ~info->mask) ^ info->mark;
        return XT_CONTINUE;
}

static bool
mark_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
        const struct xt_mark_mtinfo1 *info = par->matchinfo;

        return ((skb->mark & info->mask) == info->mark) ^ info->invert;
}

static struct xt_target mark_tg_reg[] __read_mostly = {
        {
                .name           = "MARK",
                .revision       = 2,
                .family         = NFPROTO_IPV4,
                .target         = mark_tg,
                .targetsize     = sizeof(struct xt_mark_tginfo2),
                .me             = THIS_MODULE,
        },
#if IS_ENABLED(CONFIG_IP_NF_ARPTABLES) || IS_ENABLED(CONFIG_NFT_COMPAT_ARP)
        {
                .name           = "MARK",
                .revision       = 2,
                .family         = NFPROTO_ARP,
                .target         = mark_tg,
                .targetsize     = sizeof(struct xt_mark_tginfo2),
                .me             = THIS_MODULE,
        },
#endif
#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
        {
                .name           = "MARK",
                .revision       = 2,
                .family         = NFPROTO_IPV6,
                .target         = mark_tg,
                .targetsize     = sizeof(struct xt_mark_tginfo2),
                .me             = THIS_MODULE,
        },
#endif
};

static struct xt_match mark_mt_reg __read_mostly = {
        .name           = "mark",
        .revision       = 1,
        .family         = NFPROTO_UNSPEC,
        .match          = mark_mt,
        .matchsize      = sizeof(struct xt_mark_mtinfo1),
        .me             = THIS_MODULE,
};

static int __init mark_mt_init(void)
{
        int ret;

        ret = xt_register_targets(mark_tg_reg, ARRAY_SIZE(mark_tg_reg));
        if (ret < 0)
                return ret;
        ret = xt_register_match(&mark_mt_reg);
        if (ret < 0) {
                xt_unregister_targets(mark_tg_reg, ARRAY_SIZE(mark_tg_reg));
                return ret;
        }
        return 0;
}

static void __exit mark_mt_exit(void)
{
        xt_unregister_match(&mark_mt_reg);
        xt_unregister_targets(mark_tg_reg, ARRAY_SIZE(mark_tg_reg));
}

module_init(mark_mt_init);
module_exit(mark_mt_exit);