diff options
Diffstat (limited to 'kernel/net/ipv4/netfilter/iptable_security.c')
-rw-r--r-- | kernel/net/ipv4/netfilter/iptable_security.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/kernel/net/ipv4/netfilter/iptable_security.c b/kernel/net/ipv4/netfilter/iptable_security.c new file mode 100644 index 000000000..4bce3980c --- /dev/null +++ b/kernel/net/ipv4/netfilter/iptable_security.c @@ -0,0 +1,109 @@ +/* + * "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(const struct nf_hook_ops *ops, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + const struct net *net; + + if (ops->hooknum == 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(state->in ? state->in : state->out); + return ipt_do_table(skb, ops->hooknum, state, + 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_ERR_OR_ZERO(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); |