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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))
/* Standard entry. */
struct ip6t_standard
{
struct ip6t_entry entry;
struct ip6t_standard_target target;
};
struct ip6t_error_target
{
struct ip6t_entry_target target;
char errorname[IP6T_FUNCTION_MAXNAMELEN];
};
struct ip6t_error
{
struct ip6t_entry entry;
struct ip6t_error_target target;
};
static struct
{
struct ip6t_replace repl;
struct ip6t_standard entries[3];
struct ip6t_error term;
} initial_table __initdata
= { { "filter", FILTER_VALID_HOOKS, 4,
sizeof(struct ip6t_standard) * 3 + sizeof(struct ip6t_error),
{ [NF_IP6_LOCAL_IN] = 0,
[NF_IP6_FORWARD] = sizeof(struct ip6t_standard),
[NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2 },
{ [NF_IP6_LOCAL_IN] = 0,
[NF_IP6_FORWARD] = sizeof(struct ip6t_standard),
[NF_IP6_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2 },
0, NULL, { } },
{
/* LOCAL_IN */
{ { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 },
0,
sizeof(struct ip6t_entry),
sizeof(struct ip6t_standard),
0, { 0, 0 }, { } },
{ { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } },
-NF_ACCEPT - 1 } },
/* FORWARD */
{ { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 },
0,
sizeof(struct ip6t_entry),
sizeof(struct ip6t_standard),
0, { 0, 0 }, { } },
{ { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } },
-NF_ACCEPT - 1 } },
/* LOCAL_OUT */
{ { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 },
0,
sizeof(struct ip6t_entry),
sizeof(struct ip6t_standard),
0, { 0, 0 }, { } },
{ { { { IP6T_ALIGN(sizeof(struct ip6t_standard_target)), "" } }, { } },
-NF_ACCEPT - 1 } }
},
/* ERROR */
{ { { { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, { { { 0 } } }, "", "", { 0 }, { 0 }, 0, 0, 0 },
0,
sizeof(struct ip6t_entry),
sizeof(struct ip6t_error),
0, { 0, 0 }, { } },
{ { { { IP6T_ALIGN(sizeof(struct ip6t_error_target)), IP6T_ERROR_TARGET } },
{ } },
"ERROR"
}
}
};
static struct ip6t_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 **pskb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
return ip6t_do_table(pskb, hook, in, out, &packet_filter, NULL);
}
static unsigned int
ip6t_local_out_hook(unsigned int hook,
struct sk_buff **pskb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
#if 0
/* root is playing with raw sockets. */
if ((*pskb)->len < sizeof(struct iphdr)
|| (*pskb)->nh.iph->ihl * 4 < sizeof(struct iphdr)) {
if (net_ratelimit())
printk("ip6t_hook: happy cracking.\n");
return NF_ACCEPT;
}
#endif
return ip6t_do_table(pskb, hook, in, out, &packet_filter, NULL);
}
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_hook(&ip6t_ops[0]);
if (ret < 0)
goto cleanup_table;
ret = nf_register_hook(&ip6t_ops[1]);
if (ret < 0)
goto cleanup_hook0;
ret = nf_register_hook(&ip6t_ops[2]);
if (ret < 0)
goto cleanup_hook1;
return ret;
cleanup_hook1:
nf_unregister_hook(&ip6t_ops[1]);
cleanup_hook0:
nf_unregister_hook(&ip6t_ops[0]);
cleanup_table:
ip6t_unregister_table(&packet_filter);
return ret;
}
static void __exit ip6table_filter_fini(void)
{
unsigned int i;
for (i = 0; i < sizeof(ip6t_ops)/sizeof(struct nf_hook_ops); i++)
nf_unregister_hook(&ip6t_ops[i]);
ip6t_unregister_table(&packet_filter);
}
module_init(ip6table_filter_init);
module_exit(ip6table_filter_fini);
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