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Diffstat (limited to 'net/ipv4/xfrm4_tunnel.c')
-rw-r--r--net/ipv4/xfrm4_tunnel.c144
1 files changed, 144 insertions, 0 deletions
diff --git a/net/ipv4/xfrm4_tunnel.c b/net/ipv4/xfrm4_tunnel.c
new file mode 100644
index 00000000000..413191f585f
--- /dev/null
+++ b/net/ipv4/xfrm4_tunnel.c
@@ -0,0 +1,144 @@
+/* xfrm4_tunnel.c: Generic IP tunnel transformer.
+ *
+ * Copyright (C) 2003 David S. Miller (davem@redhat.com)
+ */
+
+#include <linux/skbuff.h>
+#include <linux/module.h>
+#include <net/xfrm.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+
+static int ipip_output(struct xfrm_state *x, struct sk_buff *skb)
+{
+ struct iphdr *iph;
+
+ iph = skb->nh.iph;
+ iph->tot_len = htons(skb->len);
+ ip_send_check(iph);
+
+ return 0;
+}
+
+static int ipip_xfrm_rcv(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb)
+{
+ return 0;
+}
+
+static struct xfrm_tunnel *ipip_handler;
+static DECLARE_MUTEX(xfrm4_tunnel_sem);
+
+int xfrm4_tunnel_register(struct xfrm_tunnel *handler)
+{
+ int ret;
+
+ down(&xfrm4_tunnel_sem);
+ ret = 0;
+ if (ipip_handler != NULL)
+ ret = -EINVAL;
+ if (!ret)
+ ipip_handler = handler;
+ up(&xfrm4_tunnel_sem);
+
+ return ret;
+}
+
+EXPORT_SYMBOL(xfrm4_tunnel_register);
+
+int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler)
+{
+ int ret;
+
+ down(&xfrm4_tunnel_sem);
+ ret = 0;
+ if (ipip_handler != handler)
+ ret = -EINVAL;
+ if (!ret)
+ ipip_handler = NULL;
+ up(&xfrm4_tunnel_sem);
+
+ synchronize_net();
+
+ return ret;
+}
+
+EXPORT_SYMBOL(xfrm4_tunnel_deregister);
+
+static int ipip_rcv(struct sk_buff *skb)
+{
+ struct xfrm_tunnel *handler = ipip_handler;
+
+ /* Tunnel devices take precedence. */
+ if (handler && handler->handler(skb) == 0)
+ return 0;
+
+ return xfrm4_rcv(skb);
+}
+
+static void ipip_err(struct sk_buff *skb, u32 info)
+{
+ struct xfrm_tunnel *handler = ipip_handler;
+ u32 arg = info;
+
+ if (handler)
+ handler->err_handler(skb, &arg);
+}
+
+static int ipip_init_state(struct xfrm_state *x, void *args)
+{
+ if (!x->props.mode)
+ return -EINVAL;
+
+ if (x->encap)
+ return -EINVAL;
+
+ x->props.header_len = sizeof(struct iphdr);
+
+ return 0;
+}
+
+static void ipip_destroy(struct xfrm_state *x)
+{
+}
+
+static struct xfrm_type ipip_type = {
+ .description = "IPIP",
+ .owner = THIS_MODULE,
+ .proto = IPPROTO_IPIP,
+ .init_state = ipip_init_state,
+ .destructor = ipip_destroy,
+ .input = ipip_xfrm_rcv,
+ .output = ipip_output
+};
+
+static struct net_protocol ipip_protocol = {
+ .handler = ipip_rcv,
+ .err_handler = ipip_err,
+ .no_policy = 1,
+};
+
+static int __init ipip_init(void)
+{
+ if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
+ printk(KERN_INFO "ipip init: can't add xfrm type\n");
+ return -EAGAIN;
+ }
+ if (inet_add_protocol(&ipip_protocol, IPPROTO_IPIP) < 0) {
+ printk(KERN_INFO "ipip init: can't add protocol\n");
+ xfrm_unregister_type(&ipip_type, AF_INET);
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static void __exit ipip_fini(void)
+{
+ if (inet_del_protocol(&ipip_protocol, IPPROTO_IPIP) < 0)
+ printk(KERN_INFO "ipip close: can't remove protocol\n");
+ if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
+ printk(KERN_INFO "ipip close: can't remove xfrm type\n");
+}
+
+module_init(ipip_init);
+module_exit(ipip_fini);
+MODULE_LICENSE("GPL");