1 files changed, 85 insertions, 0 deletions
diff --git a/net/ipv6/xfrm6_mode_ro.c b/net/ipv6/xfrm6_mode_ro.c
new file mode 100644
index 000000000..da28e4407
--- /dev/null
+++ b/net/ipv6/xfrm6_mode_ro.c
@@ -0,0 +1,85 @@
+/*
+ * xfrm6_mode_ro.c - Route optimization mode for IPv6.
+ *
+ * Copyright (C)2003-2006 Helsinki University of Technology
+ * Copyright (C)2003-2006 USAGI/WIDE Project
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+/*
+ * Authors:
+ *	Noriaki TAKAMIYA @USAGI
+ *	Masahide NAKAMURA @USAGI
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/stringify.h>
+#include <linux/time.h>
+#include <net/ipv6.h>
+#include <net/xfrm.h>
+
+/* Add route optimization header space.
+ *
+ * The IP header and mutable extension headers will be moved forward to make
+ * space for the route optimization header.
+ */
+static int xfrm6_ro_output(struct xfrm_state *x, struct sk_buff *skb)
+{
+	struct ipv6hdr *iph;
+	u8 *prevhdr;
+	int hdr_len;
+
+	iph = ipv6_hdr(skb);
+
+	hdr_len = x->type->hdr_offset(x, skb, &prevhdr);
+	if (hdr_len < 0)
+		return hdr_len;
+	skb_set_mac_header(skb, (prevhdr - x->props.header_len) - skb->data);
+	skb_set_network_header(skb, -x->props.header_len);
+	skb->transport_header = skb->network_header + hdr_len;
+	__skb_pull(skb, hdr_len);
+	memmove(ipv6_hdr(skb), iph, hdr_len);
+
+	x->lastused = ktime_get_real_seconds();
+
+	return 0;
+}
+
+static struct xfrm_mode xfrm6_ro_mode = {
+	.output = xfrm6_ro_output,
+	.owner = THIS_MODULE,
+	.encap = XFRM_MODE_ROUTEOPTIMIZATION,
+};
+
+static int __init xfrm6_ro_init(void)
+{
+	return xfrm_register_mode(&xfrm6_ro_mode, AF_INET6);
+}
+
+static void __exit xfrm6_ro_exit(void)
+{
+	int err;
+
+	err = xfrm_unregister_mode(&xfrm6_ro_mode, AF_INET6);
+	BUG_ON(err);
+}
+
+module_init(xfrm6_ro_init);
+module_exit(xfrm6_ro_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_ROUTEOPTIMIZATION);