/net/ipv6/netfilter/ip6table_filter.c
C | 177 lines | 139 code | 22 blank | 16 comment | 8 complexity | f70101add1cf8302925f35827daf1cc4 MD5 | raw file
Possible License(s): GPL-2.0
- /*
- * 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_INET_LOCAL_IN) | \
- (1 << NF_INET_FORWARD) | \
- (1 << NF_INET_LOCAL_OUT))
- static struct
- {
- struct ip6t_replace repl;
- struct ip6t_standard entries[3];
- struct ip6t_error term;
- } initial_table __net_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_INET_LOCAL_IN] = 0,
- [NF_INET_FORWARD] = sizeof(struct ip6t_standard),
- [NF_INET_LOCAL_OUT] = sizeof(struct ip6t_standard) * 2
- },
- .underflow = {
- [NF_INET_LOCAL_IN] = 0,
- [NF_INET_FORWARD] = sizeof(struct ip6t_standard),
- [NF_INET_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 const struct xt_table packet_filter = {
- .name = "filter",
- .valid_hooks = FILTER_VALID_HOOKS,
- .me = THIS_MODULE,
- .af = NFPROTO_IPV6,
- };
- /* The work comes in here from netfilter.c. */
- static unsigned int
- ip6t_in_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,
- dev_net(in)->ipv6.ip6table_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,
- dev_net(out)->ipv6.ip6table_filter);
- }
- static struct nf_hook_ops ip6t_ops[] __read_mostly = {
- {
- .hook = ip6t_in_hook,
- .owner = THIS_MODULE,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_LOCAL_IN,
- .priority = NF_IP6_PRI_FILTER,
- },
- {
- .hook = ip6t_in_hook,
- .owner = THIS_MODULE,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_FORWARD,
- .priority = NF_IP6_PRI_FILTER,
- },
- {
- .hook = ip6t_local_out_hook,
- .owner = THIS_MODULE,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_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 __net_init ip6table_filter_net_init(struct net *net)
- {
- /* Register table */
- net->ipv6.ip6table_filter =
- ip6t_register_table(net, &packet_filter, &initial_table.repl);
- if (IS_ERR(net->ipv6.ip6table_filter))
- return PTR_ERR(net->ipv6.ip6table_filter);
- return 0;
- }
- static void __net_exit ip6table_filter_net_exit(struct net *net)
- {
- ip6t_unregister_table(net->ipv6.ip6table_filter);
- }
- static struct pernet_operations ip6table_filter_net_ops = {
- .init = ip6table_filter_net_init,
- .exit = ip6table_filter_net_exit,
- };
- 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;
- ret = register_pernet_subsys(&ip6table_filter_net_ops);
- 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:
- unregister_pernet_subsys(&ip6table_filter_net_ops);
- return ret;
- }
- static void __exit ip6table_filter_fini(void)
- {
- nf_unregister_hooks(ip6t_ops, ARRAY_SIZE(ip6t_ops));
- unregister_pernet_subsys(&ip6table_filter_net_ops);
- }
- module_init(ip6table_filter_init);
- module_exit(ip6table_filter_fini);