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/*
* 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 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 = tunnel6_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");
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