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_INET_LOCAL_IN) | \
23 (1 << NF_INET_FORWARD) | \
24 (1 << NF_INET_LOCAL_OUT))
28 struct ipt_replace repl
;
29 struct ipt_standard entries
[3];
30 struct ipt_error term
;
31 } initial_table __net_initdata
= {
34 .valid_hooks
= FILTER_VALID_HOOKS
,
36 .size
= sizeof(struct ipt_standard
) * 3 + sizeof(struct ipt_error
),
38 [NF_INET_LOCAL_IN
] = 0,
39 [NF_INET_FORWARD
] = sizeof(struct ipt_standard
),
40 [NF_INET_LOCAL_OUT
] = sizeof(struct ipt_standard
) * 2,
43 [NF_INET_LOCAL_IN
] = 0,
44 [NF_INET_FORWARD
] = sizeof(struct ipt_standard
),
45 [NF_INET_LOCAL_OUT
] = sizeof(struct ipt_standard
) * 2,
49 IPT_STANDARD_INIT(NF_ACCEPT
), /* LOCAL_IN */
50 IPT_STANDARD_INIT(NF_ACCEPT
), /* FORWARD */
51 IPT_STANDARD_INIT(NF_ACCEPT
), /* LOCAL_OUT */
53 .term
= IPT_ERROR_INIT
, /* ERROR */
56 static struct xt_table packet_filter
= {
58 .valid_hooks
= FILTER_VALID_HOOKS
,
59 .lock
= __RW_LOCK_UNLOCKED(packet_filter
.lock
),
64 /* The work comes in here from netfilter.c. */
66 ipt_local_in_hook(unsigned int hook
,
68 const struct net_device
*in
,
69 const struct net_device
*out
,
70 int (*okfn
)(struct sk_buff
*))
72 return ipt_do_table(skb
, hook
, in
, out
,
73 nf_local_in_net(in
, out
)->ipv4
.iptable_filter
);
77 ipt_hook(unsigned int hook
,
79 const struct net_device
*in
,
80 const struct net_device
*out
,
81 int (*okfn
)(struct sk_buff
*))
83 return ipt_do_table(skb
, hook
, in
, out
,
84 nf_forward_net(in
, out
)->ipv4
.iptable_filter
);
88 ipt_local_out_hook(unsigned int hook
,
90 const struct net_device
*in
,
91 const struct net_device
*out
,
92 int (*okfn
)(struct sk_buff
*))
94 /* root is playing with raw sockets. */
95 if (skb
->len
< sizeof(struct iphdr
) ||
96 ip_hdrlen(skb
) < sizeof(struct iphdr
)) {
98 printk("iptable_filter: ignoring short SOCK_RAW "
103 return ipt_do_table(skb
, hook
, in
, out
,
104 nf_local_out_net(in
, out
)->ipv4
.iptable_filter
);
107 static struct nf_hook_ops ipt_ops
[] __read_mostly
= {
109 .hook
= ipt_local_in_hook
,
110 .owner
= THIS_MODULE
,
112 .hooknum
= NF_INET_LOCAL_IN
,
113 .priority
= NF_IP_PRI_FILTER
,
117 .owner
= THIS_MODULE
,
119 .hooknum
= NF_INET_FORWARD
,
120 .priority
= NF_IP_PRI_FILTER
,
123 .hook
= ipt_local_out_hook
,
124 .owner
= THIS_MODULE
,
126 .hooknum
= NF_INET_LOCAL_OUT
,
127 .priority
= NF_IP_PRI_FILTER
,
131 /* Default to forward because I got too much mail already. */
132 static int forward
= NF_ACCEPT
;
133 module_param(forward
, bool, 0000);
135 static int __net_init
iptable_filter_net_init(struct net
*net
)
138 net
->ipv4
.iptable_filter
=
139 ipt_register_table(net
, &packet_filter
, &initial_table
.repl
);
140 if (IS_ERR(net
->ipv4
.iptable_filter
))
141 return PTR_ERR(net
->ipv4
.iptable_filter
);
145 static void __net_exit
iptable_filter_net_exit(struct net
*net
)
147 ipt_unregister_table(net
->ipv4
.iptable_filter
);
150 static struct pernet_operations iptable_filter_net_ops
= {
151 .init
= iptable_filter_net_init
,
152 .exit
= iptable_filter_net_exit
,
155 static int __init
iptable_filter_init(void)
159 if (forward
< 0 || forward
> NF_MAX_VERDICT
) {
160 printk("iptables forward must be 0 or 1\n");
164 /* Entry 1 is the FORWARD hook */
165 initial_table
.entries
[1].target
.verdict
= -forward
- 1;
167 ret
= register_pernet_subsys(&iptable_filter_net_ops
);
172 ret
= nf_register_hooks(ipt_ops
, ARRAY_SIZE(ipt_ops
));
179 unregister_pernet_subsys(&iptable_filter_net_ops
);
183 static void __exit
iptable_filter_fini(void)
185 nf_unregister_hooks(ipt_ops
, ARRAY_SIZE(ipt_ops
));
186 unregister_pernet_subsys(&iptable_filter_net_ops
);
189 module_init(iptable_filter_init
);
190 module_exit(iptable_filter_fini
);