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 skb_push(skb, -skb_network_offset(skb)); 16 return 0; 17 } 18 19 static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb) 20 { 21 return ip_hdr(skb)->protocol; 22 } 23 24 static 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 37 static void ipip_destroy(struct xfrm_state *x) 38 { 39 } 40 41 static 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 51 static int xfrm_tunnel_rcv(struct sk_buff *skb) 52 { 53 return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr); 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 = xfrm_tunnel_rcv, 63 .err_handler = xfrm_tunnel_err, 64 .priority = 2, 65 }; 66 67 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 68 static struct xfrm_tunnel xfrm64_tunnel_handler = { 69 .handler = xfrm_tunnel_rcv, 70 .err_handler = xfrm_tunnel_err, 71 .priority = 2, 72 }; 73 #endif 74 75 static 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 98 static 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 } 109 110 module_init(ipip_init); 111 module_exit(ipip_fini); 112 MODULE_LICENSE("GPL"); 113 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_IPIP); 114