xref: /linux/net/ipv4/xfrm4_tunnel.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /* xfrm4_tunnel.c: Generic IP tunnel transformer.
2  *
3  * Copyright (C) 2003 David S. Miller (davem@redhat.com)
4  */
5 
6 #include <linux/skbuff.h>
7 #include <linux/module.h>
8 #include <linux/mutex.h>
9 #include <net/xfrm.h>
10 #include <net/ip.h>
11 #include <net/protocol.h>
12 
13 static int ipip_output(struct xfrm_state *x, struct sk_buff *skb)
14 {
15 	struct iphdr *iph;
16 
17 	iph = skb->nh.iph;
18 	iph->tot_len = htons(skb->len);
19 	ip_send_check(iph);
20 
21 	return 0;
22 }
23 
24 static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb)
25 {
26 	return 0;
27 }
28 
29 static int ipip_init_state(struct xfrm_state *x)
30 {
31 	if (x->props.mode != XFRM_MODE_TUNNEL)
32 		return -EINVAL;
33 
34 	if (x->encap)
35 		return -EINVAL;
36 
37 	x->props.header_len = sizeof(struct iphdr);
38 
39 	return 0;
40 }
41 
42 static void ipip_destroy(struct xfrm_state *x)
43 {
44 }
45 
46 static struct xfrm_type ipip_type = {
47 	.description	= "IPIP",
48 	.owner		= THIS_MODULE,
49 	.proto	     	= IPPROTO_IPIP,
50 	.init_state	= ipip_init_state,
51 	.destructor	= ipip_destroy,
52 	.input		= ipip_xfrm_rcv,
53 	.output		= ipip_output
54 };
55 
56 static int xfrm_tunnel_err(struct sk_buff *skb, u32 info)
57 {
58 	return -ENOENT;
59 }
60 
61 static struct xfrm_tunnel xfrm_tunnel_handler = {
62 	.handler	=	xfrm4_rcv,
63 	.err_handler	=	xfrm_tunnel_err,
64 	.priority	=	2,
65 };
66 
67 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
68 static struct xfrm_tunnel xfrm64_tunnel_handler = {
69 	.handler	=	xfrm4_rcv,
70 	.err_handler	=	xfrm_tunnel_err,
71 	.priority	=	2,
72 };
73 #endif
74 
75 static int __init ipip_init(void)
76 {
77 	if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
78 		printk(KERN_INFO "ipip init: can't add xfrm type\n");
79 		return -EAGAIN;
80 	}
81 
82 	if (xfrm4_tunnel_register(&xfrm_tunnel_handler, AF_INET)) {
83 		printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET\n");
84 		xfrm_unregister_type(&ipip_type, AF_INET);
85 		return -EAGAIN;
86 	}
87 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
88 	if (xfrm4_tunnel_register(&xfrm64_tunnel_handler, AF_INET6)) {
89 		printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET6\n");
90 		xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET);
91 		xfrm_unregister_type(&ipip_type, AF_INET);
92 		return -EAGAIN;
93 	}
94 #endif
95 	return 0;
96 }
97 
98 static void __exit ipip_fini(void)
99 {
100 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
101 	if (xfrm4_tunnel_deregister(&xfrm64_tunnel_handler, AF_INET6))
102 		printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET6\n");
103 #endif
104 	if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET))
105 		printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET\n");
106 	if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
107 		printk(KERN_INFO "ipip close: can't remove xfrm type\n");
108 }
109 
110 module_init(ipip_init);
111 module_exit(ipip_fini);
112 MODULE_LICENSE("GPL");
113