net/ipv4/xfrm4_tunnel.c

   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 = ip_hdr(skb);
  16
  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 sk_buff *skb)
  24 {
  25         return 0;
  26 }
  27
  28 static int ipip_init_state(struct xfrm_state *x)
  29 {
  30         if (x->props.mode != XFRM_MODE_TUNNEL)
  31                 return -EINVAL;
  32
  33         if (x->encap)
  34                 return -EINVAL;
  35
  36         x->props.header_len = sizeof(struct iphdr);
  37
  38         return 0;
  39 }
  40
  41 static void ipip_destroy(struct xfrm_state *x)
  42 {
  43 }
  44
  45 static struct xfrm_type ipip_type = {
  46         .description    = "IPIP",
  47         .owner          = THIS_MODULE,
  48         .proto          = IPPROTO_IPIP,
  49         .init_state     = ipip_init_state,
  50         .destructor     = ipip_destroy,
  51         .input          = ipip_xfrm_rcv,
  52         .output         = ipip_output
  53 };
  54
  55 static int xfrm_tunnel_err(struct sk_buff *skb, u32 info)
  56 {
  57         return -ENOENT;
  58 }
  59
  60 static struct xfrm_tunnel xfrm_tunnel_handler = {
  61         .handler        =       xfrm4_rcv,
  62         .err_handler    =       xfrm_tunnel_err,
  63         .priority       =       2,
  64 };
  65
  66 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  67 static struct xfrm_tunnel xfrm64_tunnel_handler = {
  68         .handler        =       xfrm4_rcv,
  69         .err_handler    =       xfrm_tunnel_err,
  70         .priority       =       2,
  71 };
  72 #endif
  73
  74 static int __init ipip_init(void)
  75 {
  76         if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
  77                 printk(KERN_INFO "ipip init: can't add xfrm type\n");
  78                 return -EAGAIN;
  79         }
  80
  81         if (xfrm4_tunnel_register(&xfrm_tunnel_handler, AF_INET)) {
  82                 printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET\n");
  83                 xfrm_unregister_type(&ipip_type, AF_INET);
  84                 return -EAGAIN;
  85         }
  86 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  87         if (xfrm4_tunnel_register(&xfrm64_tunnel_handler, AF_INET6)) {
  88                 printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET6\n");
  89                 xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET);
  90                 xfrm_unregister_type(&ipip_type, AF_INET);
  91                 return -EAGAIN;
  92         }
  93 #endif
  94         return 0;
  95 }
  96
  97 static void __exit ipip_fini(void)
  98 {
  99 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 100         if (xfrm4_tunnel_deregister(&xfrm64_tunnel_handler, AF_INET6))
 101                 printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET6\n");
 102 #endif
 103         if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET))
 104                 printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET\n");
 105         if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
 106                 printk(KERN_INFO "ipip close: can't remove xfrm type\n");
 107 }
 108
 109 module_init(ipip_init);
 110 module_exit(ipip_fini);
 111 MODULE_LICENSE("GPL");
 112 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_IPIP);