LXR linux/net/ipv4/xfrm4

   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
  13static int ipip_output(struct xfrm_state *x, struct sk_buff *skb)
  14{
  15        skb_push(skb, -skb_network_offset(skb));
  16        return 0;
  17}
  18
  19static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb)
  20{
  21        return ip_hdr(skb)->protocol;
  22}
  23
  24static int ipip_init_state(struct xfrm_state *x)
  25{
  26        if (x->props.mode != XFRM_MODE_TUNNEL)
  27                return -EINVAL;
  28
  29        if (x->encap)
  30                return -EINVAL;
  31
  32        x->props.header_len = sizeof(struct iphdr);
  33
  34        return 0;
  35}
  36
  37static void ipip_destroy(struct xfrm_state *x)
  38{
  39}
  40
  41static const struct xfrm_type ipip_type = {
  42        .description    = "IPIP",
  43        .owner          = THIS_MODULE,
  44        .proto          = IPPROTO_IPIP,
  45        .init_state     = ipip_init_state,
  46        .destructor     = ipip_destroy,
  47        .input          = ipip_xfrm_rcv,
  48        .output         = ipip_output
  49};
  50
  51static int xfrm_tunnel_rcv(struct sk_buff *skb)
  52{
  53        return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr);
  54}
  55
  56static int xfrm_tunnel_err(struct sk_buff *skb, u32 info)
  57{
  58        return -ENOENT;
  59}
  60
  61static struct xfrm_tunnel xfrm_tunnel_handler = {
  62        .handler        =       xfrm_tunnel_rcv,
  63        .err_handler    =       xfrm_tunnel_err,
  64        .priority       =       2,
  65};
  66
  67#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  68static struct xfrm_tunnel xfrm64_tunnel_handler = {
  69        .handler        =       xfrm_tunnel_rcv,
  70        .err_handler    =       xfrm_tunnel_err,
  71        .priority       =       2,
  72};
  73#endif
  74
  75static int __init ipip_init(void)
  76{
  77        if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
  78                printk(KERN_INFO "ipip init: can't add xfrm type\n");
  79                return -EAGAIN;
  80        }
  81
  82        if (xfrm4_tunnel_register(&xfrm_tunnel_handler, AF_INET)) {
  83                printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET\n");
  84                xfrm_unregister_type(&ipip_type, AF_INET);
  85                return -EAGAIN;
  86        }
  87#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  88        if (xfrm4_tunnel_register(&xfrm64_tunnel_handler, AF_INET6)) {
  89                printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET6\n");
  90                xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET);
  91                xfrm_unregister_type(&ipip_type, AF_INET);
  92                return -EAGAIN;
  93        }
  94#endif
  95        return 0;
  96}
  97
  98static void __exit ipip_fini(void)
  99{
 100#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 101        if (xfrm4_tunnel_deregister(&xfrm64_tunnel_handler, AF_INET6))
 102                printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET6\n");
 103#endif
 104        if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET))
 105                printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET\n");
 106        if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
 107                printk(KERN_INFO "ipip close: can't remove xfrm type\n");
 108}
 109
 110module_init(ipip_init);
 111module_exit(ipip_fini);
 112MODULE_LICENSE("GPL");
 113MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_IPIP);
 114