File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/ipv6/xfrm6_mode_ro.c b/net/ipv6/xfrm6_mode_ro.c
new file mode 100644
index 0000000..07d3657
--- /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 = get_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);