1 files changed, 113 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/iptable_security.c b/net/ipv4/netfilter/iptable_security.c
new file mode 100644
index 00000000..be45bdc4
--- /dev/null
+++ b/net/ipv4/netfilter/iptable_security.c
@@ -0,0 +1,113 @@
+/*
+ * "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);
+	if (IS_ERR(net->ipv4.iptable_security))
+		return PTR_ERR(net->ipv4.iptable_security);
+
+	return 0;
+}
+
+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);