1 files changed, 144 insertions, 0 deletions
diff --git a/net/netfilter/xt_CONNSECMARK.c b/net/netfilter/xt_CONNSECMARK.c
new file mode 100644
index 0000000..b54c375
--- /dev/null
+++ b/net/netfilter/xt_CONNSECMARK.c
@@ -0,0 +1,144 @@
+/*
+ * This module is used to copy security markings from packets
+ * to connections, and restore security markings from connections
+ * back to packets.  This would normally be performed in conjunction
+ * with the SECMARK target and state match.
+ *
+ * Based somewhat on CONNMARK:
+ *   Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com>
+ *    by Henrik Nordstrom <hno@marasystems.com>
+ *
+ * (C) 2006,2008 Red Hat, Inc., James Morris <jmorris@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/skbuff.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter/xt_CONNSECMARK.h>
+#include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_ecache.h>
+
+#define PFX "CONNSECMARK: "
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("James Morris <jmorris@redhat.com>");
+MODULE_DESCRIPTION("Xtables: target for copying between connection and security mark");
+MODULE_ALIAS("ipt_CONNSECMARK");
+MODULE_ALIAS("ip6t_CONNSECMARK");
+
+/*
+ * If the packet has a security mark and the connection does not, copy
+ * the security mark from the packet to the connection.
+ */
+static void secmark_save(const struct sk_buff *skb)
+{
+	if (skb->secmark) {
+		struct nf_conn *ct;
+		enum ip_conntrack_info ctinfo;
+
+		ct = nf_ct_get(skb, &ctinfo);
+		if (ct && !ct->secmark) {
+			ct->secmark = skb->secmark;
+			nf_conntrack_event_cache(IPCT_SECMARK, ct);
+		}
+	}
+}
+
+/*
+ * If packet has no security mark, and the connection does, restore the
+ * security mark from the connection to the packet.
+ */
+static void secmark_restore(struct sk_buff *skb)
+{
+	if (!skb->secmark) {
+		const struct nf_conn *ct;
+		enum ip_conntrack_info ctinfo;
+
+		ct = nf_ct_get(skb, &ctinfo);
+		if (ct && ct->secmark)
+			skb->secmark = ct->secmark;
+	}
+}
+
+static unsigned int
+connsecmark_tg(struct sk_buff *skb, const struct xt_target_param *par)
+{
+	const struct xt_connsecmark_target_info *info = par->targinfo;
+
+	switch (info->mode) {
+	case CONNSECMARK_SAVE:
+		secmark_save(skb);
+		break;
+
+	case CONNSECMARK_RESTORE:
+		secmark_restore(skb);
+		break;
+
+	default:
+		BUG();
+	}
+
+	return XT_CONTINUE;
+}
+
+static bool connsecmark_tg_check(const struct xt_tgchk_param *par)
+{
+	const struct xt_connsecmark_target_info *info = par->targinfo;
+
+	if (strcmp(par->table, "mangle") != 0 &&
+	    strcmp(par->table, "security") != 0) {
+		printk(KERN_INFO PFX "target only valid in the \'mangle\' "
+		       "or \'security\' tables, not \'%s\'.\n", par->table);
+		return false;
+	}
+
+	switch (info->mode) {
+	case CONNSECMARK_SAVE:
+	case CONNSECMARK_RESTORE:
+		break;
+
+	default:
+		printk(KERN_INFO PFX "invalid mode: %hu\n", info->mode);
+		return false;
+	}
+
+	if (nf_ct_l3proto_try_module_get(par->family) < 0) {
+		printk(KERN_WARNING "can't load conntrack support for "
+				    "proto=%u\n", par->family);
+		return false;
+	}
+	return true;
+}
+
+static void connsecmark_tg_destroy(const struct xt_tgdtor_param *par)
+{
+	nf_ct_l3proto_module_put(par->family);
+}
+
+static struct xt_target connsecmark_tg_reg __read_mostly = {
+	.name       = "CONNSECMARK",
+	.revision   = 0,
+	.family     = NFPROTO_UNSPEC,
+	.checkentry = connsecmark_tg_check,
+	.destroy    = connsecmark_tg_destroy,
+	.target     = connsecmark_tg,
+	.targetsize = sizeof(struct xt_connsecmark_target_info),
+	.me         = THIS_MODULE,
+};
+
+static int __init connsecmark_tg_init(void)
+{
+	return xt_register_target(&connsecmark_tg_reg);
+}
+
+static void __exit connsecmark_tg_exit(void)
+{
+	xt_unregister_target(&connsecmark_tg_reg);
+}
+
+module_init(connsecmark_tg_init);
+module_exit(connsecmark_tg_exit);