1 files changed, 118 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ipt_CONNMARK.c b/net/ipv4/netfilter/ipt_CONNMARK.c
new file mode 100644
index 00000000000..30ddd3e18eb
--- /dev/null
+++ b/net/ipv4/netfilter/ipt_CONNMARK.c
@@ -0,0 +1,118 @@
+/* This kernel module is used to modify the connection mark values, or
+ * to optionally restore the skb nfmark from the connection mark
+ *
+ * Copyright (C) 2002,2004 MARA Systems AB <http://www.marasystems.com>
+ * by Henrik Nordstrom <hno@marasystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <net/checksum.h>
+
+MODULE_AUTHOR("Henrik Nordstrom <hno@marasytems.com>");
+MODULE_DESCRIPTION("IP tables CONNMARK matching module");
+MODULE_LICENSE("GPL");
+
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_ipv4/ipt_CONNMARK.h>
+#include <linux/netfilter_ipv4/ip_conntrack.h>
+
+static unsigned int
+target(struct sk_buff **pskb,
+       const struct net_device *in,
+       const struct net_device *out,
+       unsigned int hooknum,
+       const void *targinfo,
+       void *userinfo)
+{
+	const struct ipt_connmark_target_info *markinfo = targinfo;
+	unsigned long diff;
+	unsigned long nfmark;
+	unsigned long newmark;
+
+	enum ip_conntrack_info ctinfo;
+	struct ip_conntrack *ct = ip_conntrack_get((*pskb), &ctinfo);
+	if (ct) {
+	    switch(markinfo->mode) {
+	    case IPT_CONNMARK_SET:
+		newmark = (ct->mark & ~markinfo->mask) | markinfo->mark;
+		if (newmark != ct->mark)
+		    ct->mark = newmark;
+		break;
+	    case IPT_CONNMARK_SAVE:
+		newmark = (ct->mark & ~markinfo->mask) | ((*pskb)->nfmark & markinfo->mask);
+		if (ct->mark != newmark)
+		    ct->mark = newmark;
+		break;
+	    case IPT_CONNMARK_RESTORE:
+		nfmark = (*pskb)->nfmark;
+		diff = (ct->mark ^ nfmark) & markinfo->mask;
+		if (diff != 0) {
+		    (*pskb)->nfmark = nfmark ^ diff;
+		    (*pskb)->nfcache |= NFC_ALTERED;
+		}
+		break;
+	    }
+	}
+
+	return IPT_CONTINUE;
+}
+
+static int
+checkentry(const char *tablename,
+	   const struct ipt_entry *e,
+	   void *targinfo,
+	   unsigned int targinfosize,
+	   unsigned int hook_mask)
+{
+	struct ipt_connmark_target_info *matchinfo = targinfo;
+	if (targinfosize != IPT_ALIGN(sizeof(struct ipt_connmark_target_info))) {
+		printk(KERN_WARNING "CONNMARK: targinfosize %u != %Zu\n",
+		       targinfosize,
+		       IPT_ALIGN(sizeof(struct ipt_connmark_target_info)));
+		return 0;
+	}
+
+	if (matchinfo->mode == IPT_CONNMARK_RESTORE) {
+	    if (strcmp(tablename, "mangle") != 0) {
+		    printk(KERN_WARNING "CONNMARK: restore can only be called from \"mangle\" table, not \"%s\"\n", tablename);
+		    return 0;
+	    }
+	}
+
+	return 1;
+}
+
+static struct ipt_target ipt_connmark_reg = {
+	.name = "CONNMARK",
+	.target = &target,
+	.checkentry = &checkentry,
+	.me = THIS_MODULE
+};
+
+static int __init init(void)
+{
+	return ipt_register_target(&ipt_connmark_reg);
+}
+
+static void __exit fini(void)
+{
+	ipt_unregister_target(&ipt_connmark_reg);
+}
+
+module_init(init);
+module_exit(fini);