LXR linux/net/ipv6/netfilter/ip6t

   1/*
   2 * Copyright (c) 2011 Patrick McHardy <kaber@trash.net>
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 as
   6 * published by the Free Software Foundation.
   7 *
   8 * Based on Rusty Russell's IPv6 MASQUERADE target. Development of IPv6
   9 * NAT funded by Astaro.
  10 */
  11
  12#include <linux/kernel.h>
  13#include <linux/module.h>
  14#include <linux/netdevice.h>
  15#include <linux/ipv6.h>
  16#include <linux/netfilter.h>
  17#include <linux/netfilter_ipv6.h>
  18#include <linux/netfilter/x_tables.h>
  19#include <net/netfilter/nf_nat.h>
  20#include <net/addrconf.h>
  21#include <net/ipv6.h>
  22#include <net/netfilter/ipv6/nf_nat_masquerade.h>
  23
  24static unsigned int
  25masquerade_tg6(struct sk_buff *skb, const struct xt_action_param *par)
  26{
  27        return nf_nat_masquerade_ipv6(skb, par->targinfo, xt_out(par));
  28}
  29
  30static int masquerade_tg6_checkentry(const struct xt_tgchk_param *par)
  31{
  32        const struct nf_nat_range2 *range = par->targinfo;
  33
  34        if (range->flags & NF_NAT_RANGE_MAP_IPS)
  35                return -EINVAL;
  36        return nf_ct_netns_get(par->net, par->family);
  37}
  38
  39static void masquerade_tg6_destroy(const struct xt_tgdtor_param *par)
  40{
  41        nf_ct_netns_put(par->net, par->family);
  42}
  43
  44static struct xt_target masquerade_tg6_reg __read_mostly = {
  45        .name           = "MASQUERADE",
  46        .family         = NFPROTO_IPV6,
  47        .checkentry     = masquerade_tg6_checkentry,
  48        .destroy        = masquerade_tg6_destroy,
  49        .target         = masquerade_tg6,
  50        .targetsize     = sizeof(struct nf_nat_range),
  51        .table          = "nat",
  52        .hooks          = 1 << NF_INET_POST_ROUTING,
  53        .me             = THIS_MODULE,
  54};
  55
  56static int __init masquerade_tg6_init(void)
  57{
  58        int err;
  59
  60        err = xt_register_target(&masquerade_tg6_reg);
  61        if (err)
  62                return err;
  63
  64        err = nf_nat_masquerade_ipv6_register_notifier();
  65        if (err)
  66                xt_unregister_target(&masquerade_tg6_reg);
  67
  68        return err;
  69}
  70static void __exit masquerade_tg6_exit(void)
  71{
  72        nf_nat_masquerade_ipv6_unregister_notifier();
  73        xt_unregister_target(&masquerade_tg6_reg);
  74}
  75
  76module_init(masquerade_tg6_init);
  77module_exit(masquerade_tg6_exit);
  78
  79MODULE_LICENSE("GPL");
  80MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
  81MODULE_DESCRIPTION("Xtables: automatic address SNAT");
  82