1 /* 2 * Copyright (C)2003,2004 USAGI/WIDE Project 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 17 * 18 * Authors Mitsuru KANDA <mk@linux-ipv6.org> 19 * YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> 20 */ 21 22 #include <linux/init.h> 23 #include <linux/module.h> 24 #include <linux/mutex.h> 25 #include <linux/netdevice.h> 26 #include <linux/skbuff.h> 27 #include <net/protocol.h> 28 #include <net/xfrm.h> 29 30 static struct xfrm6_tunnel *tunnel6_handlers; 31 static DEFINE_MUTEX(tunnel6_mutex); 32 33 int xfrm6_tunnel_register(struct xfrm6_tunnel *handler) 34 { 35 struct xfrm6_tunnel **pprev; 36 int ret = -EEXIST; 37 int priority = handler->priority; 38 39 mutex_lock(&tunnel6_mutex); 40 41 for (pprev = &tunnel6_handlers; *pprev; pprev = &(*pprev)->next) { 42 if ((*pprev)->priority > priority) 43 break; 44 if ((*pprev)->priority == priority) 45 goto err; 46 } 47 48 handler->next = *pprev; 49 *pprev = handler; 50 51 ret = 0; 52 53 err: 54 mutex_unlock(&tunnel6_mutex); 55 56 return ret; 57 } 58 59 EXPORT_SYMBOL(xfrm6_tunnel_register); 60 61 int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler) 62 { 63 struct xfrm6_tunnel **pprev; 64 int ret = -ENOENT; 65 66 mutex_lock(&tunnel6_mutex); 67 68 for (pprev = &tunnel6_handlers; *pprev; pprev = &(*pprev)->next) { 69 if (*pprev == handler) { 70 *pprev = handler->next; 71 ret = 0; 72 break; 73 } 74 } 75 76 mutex_unlock(&tunnel6_mutex); 77 78 synchronize_net(); 79 80 return ret; 81 } 82 83 EXPORT_SYMBOL(xfrm6_tunnel_deregister); 84 85 static int tunnel6_rcv(struct sk_buff **pskb) 86 { 87 struct sk_buff *skb = *pskb; 88 struct xfrm6_tunnel *handler; 89 90 for (handler = tunnel6_handlers; handler; handler = handler->next) 91 if (!handler->handler(skb)) 92 return 0; 93 94 kfree_skb(skb); 95 return 0; 96 } 97 98 static void tunnel6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 99 int type, int code, int offset, __u32 info) 100 { 101 struct xfrm6_tunnel *handler; 102 103 for (handler = tunnel6_handlers; handler; handler = handler->next) 104 if (!handler->err_handler(skb, opt, type, code, offset, info)) 105 break; 106 } 107 108 static struct inet6_protocol tunnel6_protocol = { 109 .handler = tunnel6_rcv, 110 .err_handler = tunnel6_err, 111 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 112 }; 113 114 static int __init tunnel6_init(void) 115 { 116 if (inet6_add_protocol(&tunnel6_protocol, IPPROTO_IPV6)) { 117 printk(KERN_ERR "tunnel6 init(): can't add protocol\n"); 118 return -EAGAIN; 119 } 120 return 0; 121 } 122 123 static void __exit tunnel6_fini(void) 124 { 125 if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6)) 126 printk(KERN_ERR "tunnel6 close: can't remove protocol\n"); 127 } 128 129 module_init(tunnel6_init); 130 module_exit(tunnel6_fini); 131 MODULE_LICENSE("GPL"); 132