| /* |
| * "security" table |
| * |
| * This is for use by Mandatory Access Control (MAC) security models, |
| * which need to be able to manage security policy in separate context |
| * to DAC. |
| * |
| * Based on iptable_mangle.c |
| * |
| * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling |
| * Copyright (C) 2000-2004 Netfilter Core Team <coreteam <at> netfilter.org> |
| * Copyright (C) 2008 Red Hat, Inc., James Morris <jmorris <at> redhat.com> |
| * |
| * 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/netfilter_ipv4/ip_tables.h> |
| #include <linux/slab.h> |
| #include <net/ip.h> |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("James Morris <jmorris <at> redhat.com>"); |
| MODULE_DESCRIPTION("iptables security table, for MAC rules"); |
| |
| #define SECURITY_VALID_HOOKS (1 << NF_INET_LOCAL_IN) | \ |
| (1 << NF_INET_FORWARD) | \ |
| (1 << NF_INET_LOCAL_OUT) |
| |
| static const struct xt_table security_table = { |
| .name = "security", |
| .valid_hooks = SECURITY_VALID_HOOKS, |
| .me = THIS_MODULE, |
| .af = NFPROTO_IPV4, |
| .priority = NF_IP_PRI_SECURITY, |
| }; |
| |
| static unsigned int |
| iptable_security_hook(unsigned int hook, struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| int (*okfn)(struct sk_buff *)) |
| { |
| const struct net *net; |
| |
| if (hook == NF_INET_LOCAL_OUT && |
| (skb->len < sizeof(struct iphdr) || |
| ip_hdrlen(skb) < sizeof(struct iphdr))) |
| /* Somebody is playing with raw sockets. */ |
| return NF_ACCEPT; |
| |
| net = dev_net((in != NULL) ? in : out); |
| return ipt_do_table(skb, hook, in, out, net->ipv4.iptable_security); |
| } |
| |
| static struct nf_hook_ops *sectbl_ops __read_mostly; |
| |
| static int __net_init iptable_security_net_init(struct net *net) |
| { |
| struct ipt_replace *repl; |
| |
| repl = ipt_alloc_initial_table(&security_table); |
| if (repl == NULL) |
| return -ENOMEM; |
| net->ipv4.iptable_security = |
| ipt_register_table(net, &security_table, repl); |
| kfree(repl); |
| return PTR_RET(net->ipv4.iptable_security); |
| } |
| |
| static void __net_exit iptable_security_net_exit(struct net *net) |
| { |
| ipt_unregister_table(net, net->ipv4.iptable_security); |
| } |
| |
| static struct pernet_operations iptable_security_net_ops = { |
| .init = iptable_security_net_init, |
| .exit = iptable_security_net_exit, |
| }; |
| |
| static int __init iptable_security_init(void) |
| { |
| int ret; |
| |
| ret = register_pernet_subsys(&iptable_security_net_ops); |
| if (ret < 0) |
| return ret; |
| |
| sectbl_ops = xt_hook_link(&security_table, iptable_security_hook); |
| if (IS_ERR(sectbl_ops)) { |
| ret = PTR_ERR(sectbl_ops); |
| goto cleanup_table; |
| } |
| |
| return ret; |
| |
| cleanup_table: |
| unregister_pernet_subsys(&iptable_security_net_ops); |
| return ret; |
| } |
| |
| static void __exit iptable_security_fini(void) |
| { |
| xt_hook_unlink(&security_table, sectbl_ops); |
| unregister_pernet_subsys(&iptable_security_net_ops); |
| } |
| |
| module_init(iptable_security_init); |
| module_exit(iptable_security_fini); |