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Linux kernel mirror (for testing)
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kernel
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linux
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 <net/xfrm.h>
9#include <net/ip.h>
10#include <net/protocol.h>
11
12static int ipip_output(struct xfrm_state *x, struct sk_buff *skb)
13{
14 struct iphdr *iph;
15
16 iph = skb->nh.iph;
17 iph->tot_len = htons(skb->len);
18 ip_send_check(iph);
19
20 return 0;
21}
22
23static int ipip_xfrm_rcv(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb)
24{
25 return 0;
26}
27
28static struct xfrm_tunnel *ipip_handler;
29static DECLARE_MUTEX(xfrm4_tunnel_sem);
30
31int xfrm4_tunnel_register(struct xfrm_tunnel *handler)
32{
33 int ret;
34
35 down(&xfrm4_tunnel_sem);
36 ret = 0;
37 if (ipip_handler != NULL)
38 ret = -EINVAL;
39 if (!ret)
40 ipip_handler = handler;
41 up(&xfrm4_tunnel_sem);
42
43 return ret;
44}
45
46EXPORT_SYMBOL(xfrm4_tunnel_register);
47
48int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler)
49{
50 int ret;
51
52 down(&xfrm4_tunnel_sem);
53 ret = 0;
54 if (ipip_handler != handler)
55 ret = -EINVAL;
56 if (!ret)
57 ipip_handler = NULL;
58 up(&xfrm4_tunnel_sem);
59
60 synchronize_net();
61
62 return ret;
63}
64
65EXPORT_SYMBOL(xfrm4_tunnel_deregister);
66
67static int ipip_rcv(struct sk_buff *skb)
68{
69 struct xfrm_tunnel *handler = ipip_handler;
70
71 /* Tunnel devices take precedence. */
72 if (handler && handler->handler(skb) == 0)
73 return 0;
74
75 return xfrm4_rcv(skb);
76}
77
78static void ipip_err(struct sk_buff *skb, u32 info)
79{
80 struct xfrm_tunnel *handler = ipip_handler;
81
82 if (handler)
83 handler->err_handler(skb, info);
84}
85
86static int ipip_init_state(struct xfrm_state *x)
87{
88 if (!x->props.mode)
89 return -EINVAL;
90
91 if (x->encap)
92 return -EINVAL;
93
94 x->props.header_len = sizeof(struct iphdr);
95
96 return 0;
97}
98
99static void ipip_destroy(struct xfrm_state *x)
100{
101}
102
103static struct xfrm_type ipip_type = {
104 .description = "IPIP",
105 .owner = THIS_MODULE,
106 .proto = IPPROTO_IPIP,
107 .init_state = ipip_init_state,
108 .destructor = ipip_destroy,
109 .input = ipip_xfrm_rcv,
110 .output = ipip_output
111};
112
113static struct net_protocol ipip_protocol = {
114 .handler = ipip_rcv,
115 .err_handler = ipip_err,
116 .no_policy = 1,
117};
118
119static int __init ipip_init(void)
120{
121 if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
122 printk(KERN_INFO "ipip init: can't add xfrm type\n");
123 return -EAGAIN;
124 }
125 if (inet_add_protocol(&ipip_protocol, IPPROTO_IPIP) < 0) {
126 printk(KERN_INFO "ipip init: can't add protocol\n");
127 xfrm_unregister_type(&ipip_type, AF_INET);
128 return -EAGAIN;
129 }
130 return 0;
131}
132
133static void __exit ipip_fini(void)
134{
135 if (inet_del_protocol(&ipip_protocol, IPPROTO_IPIP) < 0)
136 printk(KERN_INFO "ipip close: can't remove protocol\n");
137 if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
138 printk(KERN_INFO "ipip close: can't remove xfrm type\n");
139}
140
141module_init(ipip_init);
142module_exit(ipip_fini);
143MODULE_LICENSE("GPL");