root/net/netfilter/xt_MARK.c

DEFINITIONS

1. mark_tg_v0
2. mark_tg_v1
3. mark_tg
4. mark_tg_check_v0
5. mark_tg_check_v1
6. mark_tg_compat_from_user_v0
7. mark_tg_compat_to_user_v0
8. mark_tg_compat_from_user_v1
9. mark_tg_compat_to_user_v1
10. mark_tg_init
11. mark_tg_exit

/*
 *      xt_MARK - Netfilter module to modify the NFMARK field of an skb
 *
 *      (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
 *      Copyright © CC Computer Consultants GmbH, 2007 - 2008
 *      Jan Engelhardt <jengelh@computergmbh.de>
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License version 2 as
 *      published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <net/checksum.h>

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

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

static unsigned int
mark_tg_v0(struct sk_buff *skb, const struct xt_target_param *par)
{
        const struct xt_mark_target_info *markinfo = par->targinfo;

        skb->mark = markinfo->mark;
        return XT_CONTINUE;
}

static unsigned int
mark_tg_v1(struct sk_buff *skb, const struct xt_target_param *par)
{
        const struct xt_mark_target_info_v1 *markinfo = par->targinfo;
        int mark = 0;

        switch (markinfo->mode) {
        case XT_MARK_SET:
                mark = markinfo->mark;
                break;

        case XT_MARK_AND:
                mark = skb->mark & markinfo->mark;
                break;

        case XT_MARK_OR:
                mark = skb->mark | markinfo->mark;
                break;
        }

        skb->mark = mark;
        return XT_CONTINUE;
}

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

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

static bool mark_tg_check_v0(const struct xt_tgchk_param *par)
{
        const struct xt_mark_target_info *markinfo = par->targinfo;

        if (markinfo->mark > 0xffffffff) {
                printk(KERN_WARNING "MARK: Only supports 32bit wide mark\n");
                return false;
        }
        return true;
}

static bool mark_tg_check_v1(const struct xt_tgchk_param *par)
{
        const struct xt_mark_target_info_v1 *markinfo = par->targinfo;

        if (markinfo->mode != XT_MARK_SET
            && markinfo->mode != XT_MARK_AND
            && markinfo->mode != XT_MARK_OR) {
                printk(KERN_WARNING "MARK: unknown mode %u\n",
                       markinfo->mode);
                return false;
        }
        if (markinfo->mark > 0xffffffff) {
                printk(KERN_WARNING "MARK: Only supports 32bit wide mark\n");
                return false;
        }
        return true;
}

#ifdef CONFIG_COMPAT
struct compat_xt_mark_target_info {
        compat_ulong_t  mark;
};

static void mark_tg_compat_from_user_v0(void *dst, void *src)
{
        const struct compat_xt_mark_target_info *cm = src;
        struct xt_mark_target_info m = {
                .mark   = cm->mark,
        };
        memcpy(dst, &m, sizeof(m));
}

static int mark_tg_compat_to_user_v0(void __user *dst, void *src)
{
        const struct xt_mark_target_info *m = src;
        struct compat_xt_mark_target_info cm = {
                .mark   = m->mark,
        };
        return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
}

struct compat_xt_mark_target_info_v1 {
        compat_ulong_t  mark;
        u_int8_t        mode;
        u_int8_t        __pad1;
        u_int16_t       __pad2;
};

static void mark_tg_compat_from_user_v1(void *dst, void *src)
{
        const struct compat_xt_mark_target_info_v1 *cm = src;
        struct xt_mark_target_info_v1 m = {
                .mark   = cm->mark,
                .mode   = cm->mode,
        };
        memcpy(dst, &m, sizeof(m));
}

static int mark_tg_compat_to_user_v1(void __user *dst, void *src)
{
        const struct xt_mark_target_info_v1 *m = src;
        struct compat_xt_mark_target_info_v1 cm = {
                .mark   = m->mark,
                .mode   = m->mode,
        };
        return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
}
#endif /* CONFIG_COMPAT */

static struct xt_target mark_tg_reg[] __read_mostly = {
        {
                .name           = "MARK",
                .family         = NFPROTO_UNSPEC,
                .revision       = 0,
                .checkentry     = mark_tg_check_v0,
                .target         = mark_tg_v0,
                .targetsize     = sizeof(struct xt_mark_target_info),
#ifdef CONFIG_COMPAT
                .compatsize     = sizeof(struct compat_xt_mark_target_info),
                .compat_from_user = mark_tg_compat_from_user_v0,
                .compat_to_user = mark_tg_compat_to_user_v0,
#endif
                .table          = "mangle",
                .me             = THIS_MODULE,
        },
        {
                .name           = "MARK",
                .family         = NFPROTO_UNSPEC,
                .revision       = 1,
                .checkentry     = mark_tg_check_v1,
                .target         = mark_tg_v1,
                .targetsize     = sizeof(struct xt_mark_target_info_v1),
#ifdef CONFIG_COMPAT
                .compatsize     = sizeof(struct compat_xt_mark_target_info_v1),
                .compat_from_user = mark_tg_compat_from_user_v1,
                .compat_to_user = mark_tg_compat_to_user_v1,
#endif
                .table          = "mangle",
                .me             = THIS_MODULE,
        },
        {
                .name           = "MARK",
                .revision       = 2,
                .family         = NFPROTO_UNSPEC,
                .target         = mark_tg,
                .targetsize     = sizeof(struct xt_mark_tginfo2),
                .me             = THIS_MODULE,
        },
};

static int __init mark_tg_init(void)
{
        return xt_register_targets(mark_tg_reg, ARRAY_SIZE(mark_tg_reg));
}

static void __exit mark_tg_exit(void)
{
        xt_unregister_targets(mark_tg_reg, ARRAY_SIZE(mark_tg_reg));
}

module_init(mark_tg_init);
module_exit(mark_tg_exit);