include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit...
[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 <linux/slab.h>
12 #include <net/icmp.h>
13 #include <net/ip.h>
14 #include <net/protocol.h>
15 #include <net/xfrm.h>
16
17 static struct xfrm_tunnel *tunnel4_handlers;
18 static struct xfrm_tunnel *tunnel64_handlers;
19 static DEFINE_MUTEX(tunnel4_mutex);
20
21 static inline struct xfrm_tunnel **fam_handlers(unsigned short family)
22 {
23         return (family == AF_INET) ? &tunnel4_handlers : &tunnel64_handlers;
24 }
25
26 int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family)
27 {
28         struct xfrm_tunnel **pprev;
29         int ret = -EEXIST;
30         int priority = handler->priority;
31
32         mutex_lock(&tunnel4_mutex);
33
34         for (pprev = fam_handlers(family); *pprev; pprev = &(*pprev)->next) {
35                 if ((*pprev)->priority > priority)
36                         break;
37                 if ((*pprev)->priority == priority)
38                         goto err;
39         }
40
41         handler->next = *pprev;
42         *pprev = handler;
43
44         ret = 0;
45
46 err:
47         mutex_unlock(&tunnel4_mutex);
48
49         return ret;
50 }
51
52 EXPORT_SYMBOL(xfrm4_tunnel_register);
53
54 int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family)
55 {
56         struct xfrm_tunnel **pprev;
57         int ret = -ENOENT;
58
59         mutex_lock(&tunnel4_mutex);
60
61         for (pprev = fam_handlers(family); *pprev; pprev = &(*pprev)->next) {
62                 if (*pprev == handler) {
63                         *pprev = handler->next;
64                         ret = 0;
65                         break;
66                 }
67         }
68
69         mutex_unlock(&tunnel4_mutex);
70
71         synchronize_net();
72
73         return ret;
74 }
75
76 EXPORT_SYMBOL(xfrm4_tunnel_deregister);
77
78 static int tunnel4_rcv(struct sk_buff *skb)
79 {
80         struct xfrm_tunnel *handler;
81
82         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
83                 goto drop;
84
85         for (handler = tunnel4_handlers; handler; handler = handler->next)
86                 if (!handler->handler(skb))
87                         return 0;
88
89         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
90
91 drop:
92         kfree_skb(skb);
93         return 0;
94 }
95
96 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
97 static int tunnel64_rcv(struct sk_buff *skb)
98 {
99         struct xfrm_tunnel *handler;
100
101         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
102                 goto drop;
103
104         for (handler = tunnel64_handlers; handler; handler = handler->next)
105                 if (!handler->handler(skb))
106                         return 0;
107
108         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
109
110 drop:
111         kfree_skb(skb);
112         return 0;
113 }
114 #endif
115
116 static void tunnel4_err(struct sk_buff *skb, u32 info)
117 {
118         struct xfrm_tunnel *handler;
119
120         for (handler = tunnel4_handlers; handler; handler = handler->next)
121                 if (!handler->err_handler(skb, info))
122                         break;
123 }
124
125 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
126 static void tunnel64_err(struct sk_buff *skb, u32 info)
127 {
128         struct xfrm_tunnel *handler;
129
130         for (handler = tunnel64_handlers; handler; handler = handler->next)
131                 if (!handler->err_handler(skb, info))
132                         break;
133 }
134 #endif
135
136 static const struct net_protocol tunnel4_protocol = {
137         .handler        =       tunnel4_rcv,
138         .err_handler    =       tunnel4_err,
139         .no_policy      =       1,
140         .netns_ok       =       1,
141 };
142
143 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
144 static const struct net_protocol tunnel64_protocol = {
145         .handler        =       tunnel64_rcv,
146         .err_handler    =       tunnel64_err,
147         .no_policy      =       1,
148         .netns_ok       =       1,
149 };
150 #endif
151
152 static int __init tunnel4_init(void)
153 {
154         if (inet_add_protocol(&tunnel4_protocol, IPPROTO_IPIP)) {
155                 printk(KERN_ERR "tunnel4 init: can't add protocol\n");
156                 return -EAGAIN;
157         }
158 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
159         if (inet_add_protocol(&tunnel64_protocol, IPPROTO_IPV6)) {
160                 printk(KERN_ERR "tunnel64 init: can't add protocol\n");
161                 inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP);
162                 return -EAGAIN;
163         }
164 #endif
165         return 0;
166 }
167
168 static void __exit tunnel4_fini(void)
169 {
170 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
171         if (inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6))
172                 printk(KERN_ERR "tunnel64 close: can't remove protocol\n");
173 #endif
174         if (inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP))
175                 printk(KERN_ERR "tunnel4 close: can't remove protocol\n");
176 }
177
178 module_init(tunnel4_init);
179 module_exit(tunnel4_fini);
180 MODULE_LICENSE("GPL");