2 * This is the 1999 rewrite of IP Firewalling, aiming for kernel 2.3.x.
4 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
5 * Copyright (C) 2000-2004 Netfilter Core Team <coreteam@netfilter.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/netfilter_ipv4/ip_tables.h>
18 MODULE_LICENSE("GPL");
19 MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
20 MODULE_DESCRIPTION("iptables filter table");
22 #define FILTER_VALID_HOOKS ((1 << NF_IP_LOCAL_IN) | (1 << NF_IP_FORWARD) | (1 << NF_IP_LOCAL_OUT))
26 struct ipt_replace repl
;
27 struct ipt_standard entries
[3];
28 struct ipt_error term
;
29 } initial_table __initdata
= {
32 .valid_hooks
= FILTER_VALID_HOOKS
,
34 .size
= sizeof(struct ipt_standard
) * 3 + sizeof(struct ipt_error
),
37 [NF_IP_FORWARD
] = sizeof(struct ipt_standard
),
38 [NF_IP_LOCAL_OUT
] = sizeof(struct ipt_standard
) * 2,
42 [NF_IP_FORWARD
] = sizeof(struct ipt_standard
),
43 [NF_IP_LOCAL_OUT
] = sizeof(struct ipt_standard
) * 2,
47 IPT_STANDARD_INIT(NF_ACCEPT
), /* LOCAL_IN */
48 IPT_STANDARD_INIT(NF_ACCEPT
), /* FORWARD */
49 IPT_STANDARD_INIT(NF_ACCEPT
), /* LOCAL_OUT */
51 .term
= IPT_ERROR_INIT
, /* ERROR */
54 static struct xt_table packet_filter
= {
56 .valid_hooks
= FILTER_VALID_HOOKS
,
61 /* The work comes in here from netfilter.c. */
63 ipt_hook(unsigned int hook
,
65 const struct net_device
*in
,
66 const struct net_device
*out
,
67 int (*okfn
)(struct sk_buff
*))
69 return ipt_do_table(skb
, hook
, in
, out
, &packet_filter
);
73 ipt_local_out_hook(unsigned int hook
,
75 const struct net_device
*in
,
76 const struct net_device
*out
,
77 int (*okfn
)(struct sk_buff
*))
79 /* root is playing with raw sockets. */
80 if (skb
->len
< sizeof(struct iphdr
) ||
81 ip_hdrlen(skb
) < sizeof(struct iphdr
)) {
83 printk("iptable_filter: ignoring short SOCK_RAW "
88 return ipt_do_table(skb
, hook
, in
, out
, &packet_filter
);
91 static struct nf_hook_ops ipt_ops
[] = {
96 .hooknum
= NF_IP_LOCAL_IN
,
97 .priority
= NF_IP_PRI_FILTER
,
101 .owner
= THIS_MODULE
,
103 .hooknum
= NF_IP_FORWARD
,
104 .priority
= NF_IP_PRI_FILTER
,
107 .hook
= ipt_local_out_hook
,
108 .owner
= THIS_MODULE
,
110 .hooknum
= NF_IP_LOCAL_OUT
,
111 .priority
= NF_IP_PRI_FILTER
,
115 /* Default to forward because I got too much mail already. */
116 static int forward
= NF_ACCEPT
;
117 module_param(forward
, bool, 0000);
119 static int __init
iptable_filter_init(void)
123 if (forward
< 0 || forward
> NF_MAX_VERDICT
) {
124 printk("iptables forward must be 0 or 1\n");
128 /* Entry 1 is the FORWARD hook */
129 initial_table
.entries
[1].target
.verdict
= -forward
- 1;
132 ret
= ipt_register_table(&packet_filter
, &initial_table
.repl
);
137 ret
= nf_register_hooks(ipt_ops
, ARRAY_SIZE(ipt_ops
));
139 ipt_unregister_table(&packet_filter
);
145 static void __exit
iptable_filter_fini(void)
147 nf_unregister_hooks(ipt_ops
, ARRAY_SIZE(ipt_ops
));
148 ipt_unregister_table(&packet_filter
);
151 module_init(iptable_filter_init
);
152 module_exit(iptable_filter_fini
);