LXR linux/net/netfilter/xt

   1// SPDX-License-Identifier: GPL-2.0-only
   2/* IP tables module for matching the routing realm
   3 *
   4 * (C) 2003 by Sampsa Ranta <sampsa@netsonic.fi>
   5 */
   6
   7#include <linux/module.h>
   8#include <linux/skbuff.h>
   9#include <linux/netdevice.h>
  10#include <net/route.h>
  11
  12#include <linux/netfilter_ipv4.h>
  13#include <linux/netfilter/xt_realm.h>
  14#include <linux/netfilter/x_tables.h>
  15
  16MODULE_AUTHOR("Sampsa Ranta <sampsa@netsonic.fi>");
  17MODULE_LICENSE("GPL");
  18MODULE_DESCRIPTION("Xtables: Routing realm match");
  19MODULE_ALIAS("ipt_realm");
  20
  21static bool
  22realm_mt(const struct sk_buff *skb, struct xt_action_param *par)
  23{
  24        const struct xt_realm_info *info = par->matchinfo;
  25        const struct dst_entry *dst = skb_dst(skb);
  26
  27        return (info->id == (dst->tclassid & info->mask)) ^ info->invert;
  28}
  29
  30static struct xt_match realm_mt_reg __read_mostly = {
  31        .name           = "realm",
  32        .match          = realm_mt,
  33        .matchsize      = sizeof(struct xt_realm_info),
  34        .hooks          = (1 << NF_INET_POST_ROUTING) | (1 << NF_INET_FORWARD) |
  35                          (1 << NF_INET_LOCAL_OUT) | (1 << NF_INET_LOCAL_IN),
  36        .family         = NFPROTO_UNSPEC,
  37        .me             = THIS_MODULE
  38};
  39
  40static int __init realm_mt_init(void)
  41{
  42        return xt_register_match(&realm_mt_reg);
  43}
  44
  45static void __exit realm_mt_exit(void)
  46{
  47        xt_unregister_match(&realm_mt_reg);
  48}
  49
  50module_init(realm_mt_init);
  51module_exit(realm_mt_exit);
  52