1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * "security" table for IPv6 4 * 5 * This is for use by Mandatory Access Control (MAC) security models, 6 * which need to be able to manage security policy in separate context 7 * to DAC. 8 * 9 * Based on iptable_mangle.c 10 * 11 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling 12 * Copyright (C) 2000-2004 Netfilter Core Team <coreteam <at> netfilter.org> 13 * Copyright (C) 2008 Red Hat, Inc., James Morris <jmorris <at> redhat.com> 14 */ 15 #include <linux/module.h> 16 #include <linux/netfilter_ipv6/ip6_tables.h> 17 #include <linux/slab.h> 18 19 MODULE_LICENSE("GPL"); 20 MODULE_AUTHOR("James Morris <jmorris <at> redhat.com>"); 21 MODULE_DESCRIPTION("ip6tables security table, for MAC rules"); 22 23 #define SECURITY_VALID_HOOKS (1 << NF_INET_LOCAL_IN) | \ 24 (1 << NF_INET_FORWARD) | \ 25 (1 << NF_INET_LOCAL_OUT) 26 27 static int __net_init ip6table_security_table_init(struct net *net); 28 29 static const struct xt_table security_table = { 30 .name = "security", 31 .valid_hooks = SECURITY_VALID_HOOKS, 32 .me = THIS_MODULE, 33 .af = NFPROTO_IPV6, 34 .priority = NF_IP6_PRI_SECURITY, 35 .table_init = ip6table_security_table_init, 36 }; 37 38 static unsigned int 39 ip6table_security_hook(void *priv, struct sk_buff *skb, 40 const struct nf_hook_state *state) 41 { 42 return ip6t_do_table(skb, state, state->net->ipv6.ip6table_security); 43 } 44 45 static struct nf_hook_ops *sectbl_ops __read_mostly; 46 47 static int __net_init ip6table_security_table_init(struct net *net) 48 { 49 struct ip6t_replace *repl; 50 int ret; 51 52 if (net->ipv6.ip6table_security) 53 return 0; 54 55 repl = ip6t_alloc_initial_table(&security_table); 56 if (repl == NULL) 57 return -ENOMEM; 58 ret = ip6t_register_table(net, &security_table, repl, sectbl_ops, 59 &net->ipv6.ip6table_security); 60 kfree(repl); 61 return ret; 62 } 63 64 static void __net_exit ip6table_security_net_pre_exit(struct net *net) 65 { 66 if (net->ipv6.ip6table_security) 67 ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_security, 68 sectbl_ops); 69 } 70 71 static void __net_exit ip6table_security_net_exit(struct net *net) 72 { 73 if (!net->ipv6.ip6table_security) 74 return; 75 ip6t_unregister_table_exit(net, net->ipv6.ip6table_security); 76 net->ipv6.ip6table_security = NULL; 77 } 78 79 static struct pernet_operations ip6table_security_net_ops = { 80 .pre_exit = ip6table_security_net_pre_exit, 81 .exit = ip6table_security_net_exit, 82 }; 83 84 static int __init ip6table_security_init(void) 85 { 86 int ret; 87 88 sectbl_ops = xt_hook_ops_alloc(&security_table, ip6table_security_hook); 89 if (IS_ERR(sectbl_ops)) 90 return PTR_ERR(sectbl_ops); 91 92 ret = register_pernet_subsys(&ip6table_security_net_ops); 93 if (ret < 0) { 94 kfree(sectbl_ops); 95 return ret; 96 } 97 98 ret = ip6table_security_table_init(&init_net); 99 if (ret) { 100 unregister_pernet_subsys(&ip6table_security_net_ops); 101 kfree(sectbl_ops); 102 } 103 return ret; 104 } 105 106 static void __exit ip6table_security_fini(void) 107 { 108 unregister_pernet_subsys(&ip6table_security_net_ops); 109 kfree(sectbl_ops); 110 } 111 112 module_init(ip6table_security_init); 113 module_exit(ip6table_security_fini); 114