1 /* 2 * "security" table 3 * 4 * This is for use by Mandatory Access Control (MAC) security models, 5 * which need to be able to manage security policy in separate context 6 * to DAC. 7 * 8 * Based on iptable_mangle.c 9 * 10 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling 11 * Copyright (C) 2000-2004 Netfilter Core Team <coreteam <at> netfilter.org> 12 * Copyright (C) 2008 Red Hat, Inc., James Morris <jmorris <at> redhat.com> 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License version 2 as 16 * published by the Free Software Foundation. 17 */ 18 #include <linux/module.h> 19 #include <linux/netfilter_ipv4/ip_tables.h> 20 #include <linux/slab.h> 21 #include <net/ip.h> 22 23 MODULE_LICENSE("GPL"); 24 MODULE_AUTHOR("James Morris <jmorris <at> redhat.com>"); 25 MODULE_DESCRIPTION("iptables security table, for MAC rules"); 26 27 #define SECURITY_VALID_HOOKS (1 << NF_INET_LOCAL_IN) | \ 28 (1 << NF_INET_FORWARD) | \ 29 (1 << NF_INET_LOCAL_OUT) 30 31 static int __net_init iptable_security_table_init(struct net *net); 32 33 static const struct xt_table security_table = { 34 .name = "security", 35 .valid_hooks = SECURITY_VALID_HOOKS, 36 .me = THIS_MODULE, 37 .af = NFPROTO_IPV4, 38 .priority = NF_IP_PRI_SECURITY, 39 .table_init = iptable_security_table_init, 40 }; 41 42 static unsigned int 43 iptable_security_hook(void *priv, struct sk_buff *skb, 44 const struct nf_hook_state *state) 45 { 46 return ipt_do_table(skb, state, state->net->ipv4.iptable_security); 47 } 48 49 static struct nf_hook_ops *sectbl_ops __read_mostly; 50 51 static int __net_init iptable_security_table_init(struct net *net) 52 { 53 struct ipt_replace *repl; 54 int ret; 55 56 if (net->ipv4.iptable_security) 57 return 0; 58 59 repl = ipt_alloc_initial_table(&security_table); 60 if (repl == NULL) 61 return -ENOMEM; 62 ret = ipt_register_table(net, &security_table, repl, sectbl_ops, 63 &net->ipv4.iptable_security); 64 kfree(repl); 65 return ret; 66 } 67 68 static void __net_exit iptable_security_net_exit(struct net *net) 69 { 70 if (!net->ipv4.iptable_security) 71 return; 72 73 ipt_unregister_table(net, net->ipv4.iptable_security, sectbl_ops); 74 net->ipv4.iptable_security = NULL; 75 } 76 77 static struct pernet_operations iptable_security_net_ops = { 78 .exit = iptable_security_net_exit, 79 }; 80 81 static int __init iptable_security_init(void) 82 { 83 int ret; 84 85 sectbl_ops = xt_hook_ops_alloc(&security_table, iptable_security_hook); 86 if (IS_ERR(sectbl_ops)) 87 return PTR_ERR(sectbl_ops); 88 89 ret = register_pernet_subsys(&iptable_security_net_ops); 90 if (ret < 0) { 91 kfree(sectbl_ops); 92 return ret; 93 } 94 95 ret = iptable_security_table_init(&init_net); 96 if (ret) { 97 unregister_pernet_subsys(&iptable_security_net_ops); 98 kfree(sectbl_ops); 99 } 100 101 return ret; 102 } 103 104 static void __exit iptable_security_fini(void) 105 { 106 unregister_pernet_subsys(&iptable_security_net_ops); 107 kfree(sectbl_ops); 108 } 109 110 module_init(iptable_security_init); 111 module_exit(iptable_security_fini); 112