Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 | ||
12 | static 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 | ||
23 | static int ipip_xfrm_rcv(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) | |
24 | { | |
25 | return 0; | |
26 | } | |
27 | ||
28 | static struct xfrm_tunnel *ipip_handler; | |
29 | static DECLARE_MUTEX(xfrm4_tunnel_sem); | |
30 | ||
31 | int 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 | ||
46 | EXPORT_SYMBOL(xfrm4_tunnel_register); | |
47 | ||
48 | int 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 | ||
65 | EXPORT_SYMBOL(xfrm4_tunnel_deregister); | |
66 | ||
67 | static 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 | ||
78 | static void ipip_err(struct sk_buff *skb, u32 info) | |
79 | { | |
80 | struct xfrm_tunnel *handler = ipip_handler; | |
1da177e4 LT |
81 | |
82 | if (handler) | |
0303770d | 83 | handler->err_handler(skb, info); |
1da177e4 LT |
84 | } |
85 | ||
72cb6962 | 86 | static int ipip_init_state(struct xfrm_state *x) |
1da177e4 LT |
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 | ||
99 | static void ipip_destroy(struct xfrm_state *x) | |
100 | { | |
101 | } | |
102 | ||
103 | static 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 | ||
113 | static struct net_protocol ipip_protocol = { | |
114 | .handler = ipip_rcv, | |
115 | .err_handler = ipip_err, | |
116 | .no_policy = 1, | |
117 | }; | |
118 | ||
119 | static 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 | ||
133 | static 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 | ||
141 | module_init(ipip_init); | |
142 | module_exit(ipip_fini); | |
143 | MODULE_LICENSE("GPL"); |