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; 16 17 iph = skb->nh.iph; 18 iph->tot_len = htons(skb->len); 19 ip_send_check(iph); 20 21 return 0; 22 } 23 24 static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb) 25 { 26 return 0; 27 } 28 29 static int ipip_init_state(struct xfrm_state *x) 30 { 31 if (!x->props.mode) 32 return -EINVAL; 33 34 if (x->encap) 35 return -EINVAL; 36 37 x->props.header_len = sizeof(struct iphdr); 38 39 return 0; 40 } 41 42 static void ipip_destroy(struct xfrm_state *x) 43 { 44 } 45 46 static struct xfrm_type ipip_type = { 47 .description = "IPIP", 48 .owner = THIS_MODULE, 49 .proto = IPPROTO_IPIP, 50 .init_state = ipip_init_state, 51 .destructor = ipip_destroy, 52 .input = ipip_xfrm_rcv, 53 .output = ipip_output 54 }; 55 56 static int xfrm_tunnel_err(struct sk_buff *skb, u32 info) 57 { 58 return -ENOENT; 59 } 60 61 static struct xfrm_tunnel xfrm_tunnel_handler = { 62 .handler = xfrm4_rcv, 63 .err_handler = xfrm_tunnel_err, 64 .priority = 2, 65 }; 66 67 static int __init ipip_init(void) 68 { 69 if (xfrm_register_type(&ipip_type, AF_INET) < 0) { 70 printk(KERN_INFO "ipip init: can't add xfrm type\n"); 71 return -EAGAIN; 72 } 73 if (xfrm4_tunnel_register(&xfrm_tunnel_handler)) { 74 printk(KERN_INFO "ipip init: can't add xfrm handler\n"); 75 xfrm_unregister_type(&ipip_type, AF_INET); 76 return -EAGAIN; 77 } 78 return 0; 79 } 80 81 static void __exit ipip_fini(void) 82 { 83 if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler)) 84 printk(KERN_INFO "ipip close: can't remove xfrm handler\n"); 85 if (xfrm_unregister_type(&ipip_type, AF_INET) < 0) 86 printk(KERN_INFO "ipip close: can't remove xfrm type\n"); 87 } 88 89 module_init(ipip_init); 90 module_exit(ipip_fini); 91 MODULE_LICENSE("GPL"); 92