/* * Copyright (C)2003,2004 USAGI/WIDE Project * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see <http://www.gnu.org/licenses/>. * * Authors Mitsuru KANDA <mk@linux-ipv6.org> * YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> */ #define pr_fmt(fmt) "IPv6: " fmt #include <linux/icmpv6.h> #include <linux/init.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/slab.h> #include <net/ipv6.h> #include <net/protocol.h> #include <net/xfrm.h> static struct xfrm6_tunnel __rcu *tunnel6_handlers __read_mostly; static struct xfrm6_tunnel __rcu *tunnel46_handlers __read_mostly; static DEFINE_MUTEX(tunnel6_mutex); int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family) { struct xfrm6_tunnel __rcu **pprev; struct xfrm6_tunnel *t; int ret = -EEXIST; int priority = handler->priority; mutex_lock(&tunnel6_mutex); for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers; (t = rcu_dereference_protected(*pprev, lockdep_is_held(&tunnel6_mutex))) != NULL; pprev = &t->next) { if (t->priority > priority) break; if (t->priority == priority) goto err; } handler->next = *pprev; rcu_assign_pointer(*pprev, handler); ret = 0; err: mutex_unlock(&tunnel6_mutex); return ret; } EXPORT_SYMBOL(xfrm6_tunnel_register); int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family) { struct xfrm6_tunnel __rcu **pprev; struct xfrm6_tunnel *t; int ret = -ENOENT; mutex_lock(&tunnel6_mutex); for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers; (t = rcu_dereference_protected(*pprev, lockdep_is_held(&tunnel6_mutex))) != NULL; pprev = &t->next) { if (t == handler) { *pprev = handler->next; ret = 0; break; } } mutex_unlock(&tunnel6_mutex); synchronize_net(); return ret; } EXPORT_SYMBOL(xfrm6_tunnel_deregister); #define for_each_tunnel_rcu(head, handler) \ for (handler = rcu_dereference(head); \ handler != NULL; \ handler = rcu_dereference(handler->next)) \ static int tunnel6_rcv(struct sk_buff *skb) { struct xfrm6_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) goto drop; for_each_tunnel_rcu(tunnel6_handlers, handler) if (!handler->handler(skb)) return 0; icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } static int tunnel46_rcv(struct sk_buff *skb) { struct xfrm6_tunnel *handler; if (!pskb_may_pull(skb, sizeof(struct iphdr))) goto drop; for_each_tunnel_rcu(tunnel46_handlers, handler) if (!handler->handler(skb)) return 0; icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); drop: kfree_skb(skb); return 0; } static void tunnel6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, u8 type, u8 code, int offset, __be32 info) { struct xfrm6_tunnel *handler; for_each_tunnel_rcu(tunnel6_handlers, handler) if (!handler->err_handler(skb, opt, type, code, offset, info)) break; } static void tunnel46_err(struct sk_buff *skb, struct inet6_skb_parm *opt, u8 type, u8 code, int offset, __be32 info) { struct xfrm6_tunnel *handler; for_each_tunnel_rcu(tunnel46_handlers, handler) if (!handler->err_handler(skb, opt, type, code, offset, info)) break; } static const struct inet6_protocol tunnel6_protocol = { .handler = tunnel6_rcv, .err_handler = tunnel6_err, .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, }; static const struct inet6_protocol tunnel46_protocol = { .handler = tunnel46_rcv, .err_handler = tunnel46_err, .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, }; static int __init tunnel6_init(void) { if (inet6_add_protocol(&tunnel6_protocol, IPPROTO_IPV6)) { pr_err("%s: can't add protocol\n", __func__); return -EAGAIN; } if (inet6_add_protocol(&tunnel46_protocol, IPPROTO_IPIP)) { pr_err("%s: can't add protocol\n", __func__); inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6); return -EAGAIN; } return 0; } static void __exit tunnel6_fini(void) { if (inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP)) pr_err("%s: can't remove protocol\n", __func__); if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6)) pr_err("%s: can't remove protocol\n", __func__); } module_init(tunnel6_init); module_exit(tunnel6_fini); MODULE_LICENSE("GPL");