[INET]: Move no-tunnel ICMP error to tunnel4/tunnel6
[linux-2.6.git] / net / ipv4 / tunnel4.c
1 /* tunnel4.c: Generic IP tunnel transformer.
2  *
3  * Copyright (C) 2003 David S. Miller (davem@redhat.com)
4  */
5
6 #include <linux/init.h>
7 #include <linux/module.h>
8 #include <linux/mutex.h>
9 #include <linux/netdevice.h>
10 #include <linux/skbuff.h>
11 #include <net/icmp.h>
12 #include <net/ip.h>
13 #include <net/protocol.h>
14 #include <net/xfrm.h>
15
16 static struct xfrm_tunnel *tunnel4_handlers;
17 static DEFINE_MUTEX(tunnel4_mutex);
18
19 int xfrm4_tunnel_register(struct xfrm_tunnel *handler)
20 {
21         struct xfrm_tunnel **pprev;
22         int ret = -EEXIST;
23         int priority = handler->priority;
24
25         mutex_lock(&tunnel4_mutex);
26
27         for (pprev = &tunnel4_handlers; *pprev; pprev = &(*pprev)->next) {
28                 if ((*pprev)->priority > priority)
29                         break;
30                 if ((*pprev)->priority == priority)
31                         goto err;
32         }
33
34         handler->next = *pprev;
35         *pprev = handler;
36
37         ret = 0;
38
39 err:
40         mutex_unlock(&tunnel4_mutex);
41
42         return ret;
43 }
44
45 EXPORT_SYMBOL(xfrm4_tunnel_register);
46
47 int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler)
48 {
49         struct xfrm_tunnel **pprev;
50         int ret = -ENOENT;
51
52         mutex_lock(&tunnel4_mutex);
53
54         for (pprev = &tunnel4_handlers; *pprev; pprev = &(*pprev)->next) {
55                 if (*pprev == handler) {
56                         *pprev = handler->next;
57                         ret = 0;
58                         break;
59                 }
60         }
61
62         mutex_unlock(&tunnel4_mutex);
63
64         synchronize_net();
65
66         return ret;
67 }
68
69 EXPORT_SYMBOL(xfrm4_tunnel_deregister);
70
71 static int tunnel4_rcv(struct sk_buff *skb)
72 {
73         struct xfrm_tunnel *handler;
74
75         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
76                 goto drop;
77
78         for (handler = tunnel4_handlers; handler; handler = handler->next)
79                 if (!handler->handler(skb))
80                         return 0;
81
82         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
83
84 drop:
85         kfree_skb(skb);
86         return 0;
87 }
88
89 static void tunnel4_err(struct sk_buff *skb, u32 info)
90 {
91         struct xfrm_tunnel *handler;
92
93         for (handler = tunnel4_handlers; handler; handler = handler->next)
94                 if (!handler->err_handler(skb, info))
95                         break;
96 }
97
98 static struct net_protocol tunnel4_protocol = {
99         .handler        =       tunnel4_rcv,
100         .err_handler    =       tunnel4_err,
101         .no_policy      =       1,
102 };
103
104 static int __init tunnel4_init(void)
105 {
106         if (inet_add_protocol(&tunnel4_protocol, IPPROTO_IPIP)) {
107                 printk(KERN_ERR "tunnel4 init: can't add protocol\n");
108                 return -EAGAIN;
109         }
110         return 0;
111 }
112
113 static void __exit tunnel4_fini(void)
114 {
115         if (inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP))
116                 printk(KERN_ERR "tunnel4 close: can't remove protocol\n");
117 }
118
119 module_init(tunnel4_init);
120 module_exit(tunnel4_fini);
121 MODULE_LICENSE("GPL");