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/icmpv6.h> 23#include <linux/init.h> 24#include <linux/module.h> 25#include <linux/mutex.h> 26#include <linux/netdevice.h> 27#include <linux/skbuff.h> 28#include <linux/slab.h> 29#include <net/ipv6.h> 30#include <net/protocol.h> 31#include <net/xfrm.h> 32 33static struct xfrm6_tunnel *tunnel6_handlers; 34static struct xfrm6_tunnel *tunnel46_handlers; 35static DEFINE_MUTEX(tunnel6_mutex); 36 37int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family) 38{ 39 struct xfrm6_tunnel **pprev; 40 int ret = -EEXIST; 41 int priority = handler->priority; 42 43 mutex_lock(&tunnel6_mutex); 44 45 for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers; 46 *pprev; pprev = &(*pprev)->next) { 47 if ((*pprev)->priority > priority) 48 break; 49 if ((*pprev)->priority == priority) 50 goto err; 51 } 52 53 handler->next = *pprev; 54 *pprev = handler; 55 56 ret = 0; 57 58err: 59 mutex_unlock(&tunnel6_mutex); 60 61 return ret; 62} 63 64EXPORT_SYMBOL(xfrm6_tunnel_register); 65 66int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family) 67{ 68 struct xfrm6_tunnel **pprev; 69 int ret = -ENOENT; 70 71 mutex_lock(&tunnel6_mutex); 72 73 for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers; 74 *pprev; pprev = &(*pprev)->next) { 75 if (*pprev == handler) { 76 *pprev = handler->next; 77 ret = 0; 78 break; 79 } 80 } 81 82 mutex_unlock(&tunnel6_mutex); 83 84 synchronize_net(); 85 86 return ret; 87} 88 89EXPORT_SYMBOL(xfrm6_tunnel_deregister); 90 91static int tunnel6_rcv(struct sk_buff *skb) 92{ 93 struct xfrm6_tunnel *handler; 94 95 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) 96 goto drop; 97 98 for (handler = tunnel6_handlers; handler; handler = handler->next) 99 if (!handler->handler(skb)) 100 return 0; 101 102 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 103 104drop: 105 kfree_skb(skb); 106 return 0; 107} 108 109static int tunnel46_rcv(struct sk_buff *skb) 110{ 111 struct xfrm6_tunnel *handler; 112 113 if (!pskb_may_pull(skb, sizeof(struct iphdr))) 114 goto drop; 115 116 for (handler = tunnel46_handlers; handler; handler = handler->next) 117 if (!handler->handler(skb)) 118 return 0; 119 120 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 121 122drop: 123 kfree_skb(skb); 124 return 0; 125} 126 127static void tunnel6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 128 u8 type, u8 code, int offset, __be32 info) 129{ 130 struct xfrm6_tunnel *handler; 131 132 for (handler = tunnel6_handlers; handler; handler = handler->next) 133 if (!handler->err_handler(skb, opt, type, code, offset, info)) 134 break; 135} 136 137static const struct inet6_protocol tunnel6_protocol = { 138 .handler = tunnel6_rcv, 139 .err_handler = tunnel6_err, 140 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 141}; 142 143static const struct inet6_protocol tunnel46_protocol = { 144 .handler = tunnel46_rcv, 145 .err_handler = tunnel6_err, 146 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 147}; 148 149static int __init tunnel6_init(void) 150{ 151 if (inet6_add_protocol(&tunnel6_protocol, IPPROTO_IPV6)) { 152 printk(KERN_ERR "tunnel6 init(): can't add protocol\n"); 153 return -EAGAIN; 154 } 155 if (inet6_add_protocol(&tunnel46_protocol, IPPROTO_IPIP)) { 156 printk(KERN_ERR "tunnel6 init(): can't add protocol\n"); 157 inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6); 158 return -EAGAIN; 159 } 160 return 0; 161} 162 163static void __exit tunnel6_fini(void) 164{ 165 if (inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP)) 166 printk(KERN_ERR "tunnel6 close: can't remove protocol\n"); 167 if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6)) 168 printk(KERN_ERR "tunnel6 close: can't remove protocol\n"); 169} 170 171module_init(tunnel6_init); 172module_exit(tunnel6_fini); 173MODULE_LICENSE("GPL"); 174