James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 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 <net/ip.h> |
| 21 | |
| 22 | MODULE_LICENSE("GPL"); |
| 23 | MODULE_AUTHOR("James Morris <jmorris <at> redhat.com>"); |
| 24 | MODULE_DESCRIPTION("iptables security table, for MAC rules"); |
| 25 | |
| 26 | #define SECURITY_VALID_HOOKS (1 << NF_INET_LOCAL_IN) | \ |
| 27 | (1 << NF_INET_FORWARD) | \ |
| 28 | (1 << NF_INET_LOCAL_OUT) |
| 29 | |
Jan Engelhardt | 35aad0f | 2009-08-24 14:56:30 +0200 | [diff] [blame] | 30 | static const struct xt_table security_table = { |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 31 | .name = "security", |
| 32 | .valid_hooks = SECURITY_VALID_HOOKS, |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 33 | .me = THIS_MODULE, |
Jan Engelhardt | f88e6a8 | 2009-06-13 06:25:44 +0200 | [diff] [blame] | 34 | .af = NFPROTO_IPV4, |
Jan Engelhardt | 2b95efe | 2009-06-17 13:57:48 +0200 | [diff] [blame] | 35 | .priority = NF_IP_PRI_SECURITY, |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 36 | }; |
| 37 | |
| 38 | static unsigned int |
Jan Engelhardt | 737535c | 2009-06-13 06:46:36 +0200 | [diff] [blame] | 39 | iptable_security_hook(unsigned int hook, struct sk_buff *skb, |
| 40 | const struct net_device *in, |
| 41 | const struct net_device *out, |
| 42 | int (*okfn)(struct sk_buff *)) |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 43 | { |
Jan Engelhardt | 2b21e05 | 2009-06-13 06:57:10 +0200 | [diff] [blame] | 44 | const struct net *net; |
Jan Engelhardt | 737535c | 2009-06-13 06:46:36 +0200 | [diff] [blame] | 45 | |
Jan Engelhardt | 2b21e05 | 2009-06-13 06:57:10 +0200 | [diff] [blame] | 46 | if (hook == NF_INET_LOCAL_OUT && |
| 47 | (skb->len < sizeof(struct iphdr) || |
| 48 | ip_hdrlen(skb) < sizeof(struct iphdr))) |
| 49 | /* Somebody is playing with raw sockets. */ |
| 50 | return NF_ACCEPT; |
Jan Engelhardt | 737535c | 2009-06-13 06:46:36 +0200 | [diff] [blame] | 51 | |
Jan Engelhardt | 2b21e05 | 2009-06-13 06:57:10 +0200 | [diff] [blame] | 52 | net = dev_net((in != NULL) ? in : out); |
| 53 | return ipt_do_table(skb, hook, in, out, net->ipv4.iptable_security); |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 54 | } |
| 55 | |
Jan Engelhardt | 2b95efe | 2009-06-17 13:57:48 +0200 | [diff] [blame] | 56 | static struct nf_hook_ops *sectbl_ops __read_mostly; |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 57 | |
| 58 | static int __net_init iptable_security_net_init(struct net *net) |
| 59 | { |
Jan Engelhardt | e3eaa99 | 2009-06-17 22:14:54 +0200 | [diff] [blame^] | 60 | struct ipt_replace *repl; |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 61 | |
Jan Engelhardt | e3eaa99 | 2009-06-17 22:14:54 +0200 | [diff] [blame^] | 62 | repl = ipt_alloc_initial_table(&security_table); |
| 63 | if (repl == NULL) |
| 64 | return -ENOMEM; |
| 65 | net->ipv4.iptable_security = |
| 66 | ipt_register_table(net, &security_table, repl); |
| 67 | kfree(repl); |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 68 | if (IS_ERR(net->ipv4.iptable_security)) |
| 69 | return PTR_ERR(net->ipv4.iptable_security); |
| 70 | |
| 71 | return 0; |
| 72 | } |
| 73 | |
| 74 | static void __net_exit iptable_security_net_exit(struct net *net) |
| 75 | { |
Alexey Dobriyan | f54e936 | 2010-01-18 08:25:47 +0100 | [diff] [blame] | 76 | ipt_unregister_table(net, net->ipv4.iptable_security); |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 77 | } |
| 78 | |
| 79 | static struct pernet_operations iptable_security_net_ops = { |
| 80 | .init = iptable_security_net_init, |
| 81 | .exit = iptable_security_net_exit, |
| 82 | }; |
| 83 | |
| 84 | static int __init iptable_security_init(void) |
| 85 | { |
| 86 | int ret; |
| 87 | |
| 88 | ret = register_pernet_subsys(&iptable_security_net_ops); |
| 89 | if (ret < 0) |
| 90 | return ret; |
| 91 | |
Jan Engelhardt | 2b95efe | 2009-06-17 13:57:48 +0200 | [diff] [blame] | 92 | sectbl_ops = xt_hook_link(&security_table, iptable_security_hook); |
| 93 | if (IS_ERR(sectbl_ops)) { |
| 94 | ret = PTR_ERR(sectbl_ops); |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 95 | goto cleanup_table; |
Jan Engelhardt | 2b95efe | 2009-06-17 13:57:48 +0200 | [diff] [blame] | 96 | } |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 97 | |
| 98 | return ret; |
| 99 | |
| 100 | cleanup_table: |
| 101 | unregister_pernet_subsys(&iptable_security_net_ops); |
| 102 | return ret; |
| 103 | } |
| 104 | |
| 105 | static void __exit iptable_security_fini(void) |
| 106 | { |
Jan Engelhardt | 2b95efe | 2009-06-17 13:57:48 +0200 | [diff] [blame] | 107 | xt_hook_unlink(&security_table, sectbl_ops); |
James Morris | 560ee65 | 2008-06-09 15:57:24 -0700 | [diff] [blame] | 108 | unregister_pernet_subsys(&iptable_security_net_ops); |
| 109 | } |
| 110 | |
| 111 | module_init(iptable_security_init); |
| 112 | module_exit(iptable_security_fini); |