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/*
* This is the 1999 rewrite of IP Firewalling, aiming for kernel 2.3.x.
*
* Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
* Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org>
*
* 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/moduleparam.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
MODULE_DESCRIPTION("ip6tables filter table");
#define FILTER_VALID_HOOKS ((1 << NF_IP6_LOCAL_IN) | (1 << NF_IP6_FORWARD) | (1 << NF_IP6_LOCAL_OUT))
static struct
{
struct ip6t_replace repl;
struct ip6t_standard entries[3];
struct ip6t_error term;
} initial_table __initdata = {
.repl = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
.num_entries = 4,
.size = sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error),
.hook_entry = {
[NF_IP6_LOCAL_IN] = 0,
[NF_IP6_FORWARD] = sizeof(struct ip6t_standard),
[NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
},
.underflow = {
[NF_IP6_LOCAL_IN] = 0,
[NF_IP6_FORWARD] = sizeof(struct ip6t_standard),
[NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
},
},
.entries = {
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_IN */
IP6T_STANDARD_INIT(NF_ACCEPT), /* FORWARD */
IP6T_STANDARD_INIT(NF_ACCEPT), /* LOCAL_OUT */
},
.term = IP6T_ERROR_INIT, /* ERROR */
};
static struct xt_table packet_filter = {
.name = "filter",
.valid_hooks = FILTER_VALID_HOOKS,
.lock = RW_LOCK_UNLOCKED,
.me = THIS_MODULE,
.af = AF_INET6,
};
/* The work comes in here from netfilter.c. */
static unsigned int
ip6t_hook(unsigned int hook,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
return ip6t_do_table(skb, hook, in, out, &packet_filter);
}
static unsigned int
ip6t_local_out_hook(unsigned int hook,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
#if 0
/* root is playing with raw sockets. */
if (skb->len < sizeof(struct iphdr)
|| ip_hdrlen(skb) < sizeof(struct iphdr)) {
if (net_ratelimit())
printk("ip6t_hook: happy cracking.\n");
return NF_ACCEPT;
}
#endif
return ip6t_do_table(skb, hook, in, out, &packet_filter);
}
static struct nf_hook_ops ip6t_ops[] = {
{
.hook = ip6t_hook,
.owner = THIS_MODULE,
.pf = PF_INET6,
.hooknum = NF_IP6_LOCAL_IN,
.priority = NF_IP6_PRI_FILTER,
},
{
.hook = ip6t_hook,
.owner = THIS_MODULE,
.pf = PF_INET6,
.hooknum = NF_IP6_FORWARD,
.priority = NF_IP6_PRI_FILTER,
},
{
.hook = ip6t_local_out_hook,
.owner = THIS_MODULE,
.pf = PF_INET6,
.hooknum = NF_IP6_LOCAL_OUT,
.priority = NF_IP6_PRI_FILTER,
},
};
/* Default to forward because I got too much mail already. */
static int forward = NF_ACCEPT;
module_param(forward, bool, 0000);
static int __init ip6table_filter_init(void)
{
int ret;
if (forward < 0 || forward > NF_MAX_VERDICT) {
printk("iptables forward must be 0 or 1\n");
return -EINVAL;
}
/* Entry 1 is the FORWARD hook */
initial_table.entries[1].target.verdict = -forward - 1;
/* Register table */
ret = ip6t_register_table(&packet_filter, &initial_table.repl);
if (ret < 0)
return ret;
/* Register hooks */
ret = nf_register_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
if (ret < 0)
goto cleanup_table;
return ret;
cleanup_table:
ip6t_unregister_table(&packet_filter);
return ret;
}
static void __exit ip6table_filter_fini(void)
{
nf_unregister_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
ip6t_unregister_table(&packet_filter);
}
module_init(ip6table_filter_init);
module_exit(ip6table_filter_fini);
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